Coverage Report

Created: 2022-07-08 00:21

/Users/erlendaasland/install/sqlite-3.39.0/include/sqlite3.h
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/*
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** 2001-09-15
3
**
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** The author disclaims copyright to this source code.  In place of
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** a legal notice, here is a blessing:
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**
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**    May you do good and not evil.
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**    May you find forgiveness for yourself and forgive others.
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**    May you share freely, never taking more than you give.
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**
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*************************************************************************
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** This header file defines the interface that the SQLite library
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** presents to client programs.  If a C-function, structure, datatype,
14
** or constant definition does not appear in this file, then it is
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** not a published API of SQLite, is subject to change without
16
** notice, and should not be referenced by programs that use SQLite.
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**
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** Some of the definitions that are in this file are marked as
19
** "experimental".  Experimental interfaces are normally new
20
** features recently added to SQLite.  We do not anticipate changes
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** to experimental interfaces but reserve the right to make minor changes
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** if experience from use "in the wild" suggest such changes are prudent.
23
**
24
** The official C-language API documentation for SQLite is derived
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** from comments in this file.  This file is the authoritative source
26
** on how SQLite interfaces are supposed to operate.
27
**
28
** The name of this file under configuration management is "sqlite.h.in".
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** The makefile makes some minor changes to this file (such as inserting
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** the version number) and changes its name to "sqlite3.h" as
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** part of the build process.
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*/
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#ifndef SQLITE3_H
34
#define SQLITE3_H
35
#include <stdarg.h>     /* Needed for the definition of va_list */
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37
/*
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** Make sure we can call this stuff from C++.
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*/
40
#ifdef __cplusplus
41
extern "C" {
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#endif
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44
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/*
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** Facilitate override of interface linkage and calling conventions.
47
** Be aware that these macros may not be used within this particular
48
** translation of the amalgamation and its associated header file.
49
**
50
** The SQLITE_EXTERN and SQLITE_API macros are used to instruct the
51
** compiler that the target identifier should have external linkage.
52
**
53
** The SQLITE_CDECL macro is used to set the calling convention for
54
** public functions that accept a variable number of arguments.
55
**
56
** The SQLITE_APICALL macro is used to set the calling convention for
57
** public functions that accept a fixed number of arguments.
58
**
59
** The SQLITE_STDCALL macro is no longer used and is now deprecated.
60
**
61
** The SQLITE_CALLBACK macro is used to set the calling convention for
62
** function pointers.
63
**
64
** The SQLITE_SYSAPI macro is used to set the calling convention for
65
** functions provided by the operating system.
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**
67
** Currently, the SQLITE_CDECL, SQLITE_APICALL, SQLITE_CALLBACK, and
68
** SQLITE_SYSAPI macros are used only when building for environments
69
** that require non-default calling conventions.
70
*/
71
#ifndef SQLITE_EXTERN
72
# define SQLITE_EXTERN extern
73
#endif
74
#ifndef SQLITE_API
75
# define SQLITE_API
76
#endif
77
#ifndef SQLITE_CDECL
78
# define SQLITE_CDECL
79
#endif
80
#ifndef SQLITE_APICALL
81
# define SQLITE_APICALL
82
#endif
83
#ifndef SQLITE_STDCALL
84
# define SQLITE_STDCALL SQLITE_APICALL
85
#endif
86
#ifndef SQLITE_CALLBACK
87
# define SQLITE_CALLBACK
88
#endif
89
#ifndef SQLITE_SYSAPI
90
# define SQLITE_SYSAPI
91
#endif
92
93
/*
94
** These no-op macros are used in front of interfaces to mark those
95
** interfaces as either deprecated or experimental.  New applications
96
** should not use deprecated interfaces - they are supported for backwards
97
** compatibility only.  Application writers should be aware that
98
** experimental interfaces are subject to change in point releases.
99
**
100
** These macros used to resolve to various kinds of compiler magic that
101
** would generate warning messages when they were used.  But that
102
** compiler magic ended up generating such a flurry of bug reports
103
** that we have taken it all out and gone back to using simple
104
** noop macros.
105
*/
106
#define SQLITE_DEPRECATED
107
#define SQLITE_EXPERIMENTAL
108
109
/*
110
** Ensure these symbols were not defined by some previous header file.
111
*/
112
#ifdef SQLITE_VERSION
113
# undef SQLITE_VERSION
114
#endif
115
#ifdef SQLITE_VERSION_NUMBER
116
# undef SQLITE_VERSION_NUMBER
117
#endif
118
119
/*
120
** CAPI3REF: Compile-Time Library Version Numbers
121
**
122
** ^(The [SQLITE_VERSION] C preprocessor macro in the sqlite3.h header
123
** evaluates to a string literal that is the SQLite version in the
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** format "X.Y.Z" where X is the major version number (always 3 for
125
** SQLite3) and Y is the minor version number and Z is the release number.)^
126
** ^(The [SQLITE_VERSION_NUMBER] C preprocessor macro resolves to an integer
127
** with the value (X*1000000 + Y*1000 + Z) where X, Y, and Z are the same
128
** numbers used in [SQLITE_VERSION].)^
129
** The SQLITE_VERSION_NUMBER for any given release of SQLite will also
130
** be larger than the release from which it is derived.  Either Y will
131
** be held constant and Z will be incremented or else Y will be incremented
132
** and Z will be reset to zero.
133
**
134
** Since [version 3.6.18] ([dateof:3.6.18]),
135
** SQLite source code has been stored in the
136
** <a href="http://www.fossil-scm.org/">Fossil configuration management
137
** system</a>.  ^The SQLITE_SOURCE_ID macro evaluates to
138
** a string which identifies a particular check-in of SQLite
139
** within its configuration management system.  ^The SQLITE_SOURCE_ID
140
** string contains the date and time of the check-in (UTC) and a SHA1
141
** or SHA3-256 hash of the entire source tree.  If the source code has
142
** been edited in any way since it was last checked in, then the last
143
** four hexadecimal digits of the hash may be modified.
144
**
145
** See also: [sqlite3_libversion()],
146
** [sqlite3_libversion_number()], [sqlite3_sourceid()],
147
** [sqlite_version()] and [sqlite_source_id()].
148
*/
149
#define SQLITE_VERSION        "3.39.0"
150
#define SQLITE_VERSION_NUMBER 3039000
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#define SQLITE_SOURCE_ID      "2022-06-25 14:57:57 14e166f40dbfa6e055543f8301525f2ca2e96a02a57269818b9e69e162e98918"
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/*
154
** CAPI3REF: Run-Time Library Version Numbers
155
** KEYWORDS: sqlite3_version sqlite3_sourceid
156
**
157
** These interfaces provide the same information as the [SQLITE_VERSION],
158
** [SQLITE_VERSION_NUMBER], and [SQLITE_SOURCE_ID] C preprocessor macros
159
** but are associated with the library instead of the header file.  ^(Cautious
160
** programmers might include assert() statements in their application to
161
** verify that values returned by these interfaces match the macros in
162
** the header, and thus ensure that the application is
163
** compiled with matching library and header files.
164
**
165
** <blockquote><pre>
166
** assert( sqlite3_libversion_number()==SQLITE_VERSION_NUMBER );
167
** assert( strncmp(sqlite3_sourceid(),SQLITE_SOURCE_ID,80)==0 );
168
** assert( strcmp(sqlite3_libversion(),SQLITE_VERSION)==0 );
169
** </pre></blockquote>)^
170
**
171
** ^The sqlite3_version[] string constant contains the text of [SQLITE_VERSION]
172
** macro.  ^The sqlite3_libversion() function returns a pointer to the
173
** to the sqlite3_version[] string constant.  The sqlite3_libversion()
174
** function is provided for use in DLLs since DLL users usually do not have
175
** direct access to string constants within the DLL.  ^The
176
** sqlite3_libversion_number() function returns an integer equal to
177
** [SQLITE_VERSION_NUMBER].  ^(The sqlite3_sourceid() function returns
178
** a pointer to a string constant whose value is the same as the
179
** [SQLITE_SOURCE_ID] C preprocessor macro.  Except if SQLite is built
180
** using an edited copy of [the amalgamation], then the last four characters
181
** of the hash might be different from [SQLITE_SOURCE_ID].)^
182
**
183
** See also: [sqlite_version()] and [sqlite_source_id()].
184
*/
185
SQLITE_API SQLITE_EXTERN const char sqlite3_version[];
186
SQLITE_API const char *sqlite3_libversion(void);
187
SQLITE_API const char *sqlite3_sourceid(void);
188
SQLITE_API int sqlite3_libversion_number(void);
189
190
/*
191
** CAPI3REF: Run-Time Library Compilation Options Diagnostics
192
**
193
** ^The sqlite3_compileoption_used() function returns 0 or 1
194
** indicating whether the specified option was defined at
195
** compile time.  ^The SQLITE_ prefix may be omitted from the
196
** option name passed to sqlite3_compileoption_used().
197
**
198
** ^The sqlite3_compileoption_get() function allows iterating
199
** over the list of options that were defined at compile time by
200
** returning the N-th compile time option string.  ^If N is out of range,
201
** sqlite3_compileoption_get() returns a NULL pointer.  ^The SQLITE_
202
** prefix is omitted from any strings returned by
203
** sqlite3_compileoption_get().
204
**
205
** ^Support for the diagnostic functions sqlite3_compileoption_used()
206
** and sqlite3_compileoption_get() may be omitted by specifying the
207
** [SQLITE_OMIT_COMPILEOPTION_DIAGS] option at compile time.
208
**
209
** See also: SQL functions [sqlite_compileoption_used()] and
210
** [sqlite_compileoption_get()] and the [compile_options pragma].
211
*/
212
#ifndef SQLITE_OMIT_COMPILEOPTION_DIAGS
213
SQLITE_API int sqlite3_compileoption_used(const char *zOptName);
214
SQLITE_API const char *sqlite3_compileoption_get(int N);
215
#else
216
# define sqlite3_compileoption_used(X) 0
217
# define sqlite3_compileoption_get(X)  ((void*)0)
218
#endif
219
220
/*
221
** CAPI3REF: Test To See If The Library Is Threadsafe
222
**
223
** ^The sqlite3_threadsafe() function returns zero if and only if
224
** SQLite was compiled with mutexing code omitted due to the
225
** [SQLITE_THREADSAFE] compile-time option being set to 0.
226
**
227
** SQLite can be compiled with or without mutexes.  When
228
** the [SQLITE_THREADSAFE] C preprocessor macro is 1 or 2, mutexes
229
** are enabled and SQLite is threadsafe.  When the
230
** [SQLITE_THREADSAFE] macro is 0,
231
** the mutexes are omitted.  Without the mutexes, it is not safe
232
** to use SQLite concurrently from more than one thread.
233
**
234
** Enabling mutexes incurs a measurable performance penalty.
235
** So if speed is of utmost importance, it makes sense to disable
236
** the mutexes.  But for maximum safety, mutexes should be enabled.
237
** ^The default behavior is for mutexes to be enabled.
238
**
239
** This interface can be used by an application to make sure that the
240
** version of SQLite that it is linking against was compiled with
241
** the desired setting of the [SQLITE_THREADSAFE] macro.
242
**
243
** This interface only reports on the compile-time mutex setting
244
** of the [SQLITE_THREADSAFE] flag.  If SQLite is compiled with
245
** SQLITE_THREADSAFE=1 or =2 then mutexes are enabled by default but
246
** can be fully or partially disabled using a call to [sqlite3_config()]
247
** with the verbs [SQLITE_CONFIG_SINGLETHREAD], [SQLITE_CONFIG_MULTITHREAD],
248
** or [SQLITE_CONFIG_SERIALIZED].  ^(The return value of the
249
** sqlite3_threadsafe() function shows only the compile-time setting of
250
** thread safety, not any run-time changes to that setting made by
251
** sqlite3_config(). In other words, the return value from sqlite3_threadsafe()
252
** is unchanged by calls to sqlite3_config().)^
253
**
254
** See the [threading mode] documentation for additional information.
255
*/
256
SQLITE_API int sqlite3_threadsafe(void);
257
258
/*
259
** CAPI3REF: Database Connection Handle
260
** KEYWORDS: {database connection} {database connections}
261
**
262
** Each open SQLite database is represented by a pointer to an instance of
263
** the opaque structure named "sqlite3".  It is useful to think of an sqlite3
264
** pointer as an object.  The [sqlite3_open()], [sqlite3_open16()], and
265
** [sqlite3_open_v2()] interfaces are its constructors, and [sqlite3_close()]
266
** and [sqlite3_close_v2()] are its destructors.  There are many other
267
** interfaces (such as
268
** [sqlite3_prepare_v2()], [sqlite3_create_function()], and
269
** [sqlite3_busy_timeout()] to name but three) that are methods on an
270
** sqlite3 object.
271
*/
272
typedef struct sqlite3 sqlite3;
273
274
/*
275
** CAPI3REF: 64-Bit Integer Types
276
** KEYWORDS: sqlite_int64 sqlite_uint64
277
**
278
** Because there is no cross-platform way to specify 64-bit integer types
279
** SQLite includes typedefs for 64-bit signed and unsigned integers.
280
**
281
** The sqlite3_int64 and sqlite3_uint64 are the preferred type definitions.
282
** The sqlite_int64 and sqlite_uint64 types are supported for backwards
283
** compatibility only.
284
**
285
** ^The sqlite3_int64 and sqlite_int64 types can store integer values
286
** between -9223372036854775808 and +9223372036854775807 inclusive.  ^The
287
** sqlite3_uint64 and sqlite_uint64 types can store integer values
288
** between 0 and +18446744073709551615 inclusive.
289
*/
290
#ifdef SQLITE_INT64_TYPE
291
  typedef SQLITE_INT64_TYPE sqlite_int64;
292
# ifdef SQLITE_UINT64_TYPE
293
    typedef SQLITE_UINT64_TYPE sqlite_uint64;
294
# else
295
    typedef unsigned SQLITE_INT64_TYPE sqlite_uint64;
296
# endif
297
#elif defined(_MSC_VER) || defined(__BORLANDC__)
298
  typedef __int64 sqlite_int64;
299
  typedef unsigned __int64 sqlite_uint64;
300
#else
301
  typedef long long int sqlite_int64;
302
  typedef unsigned long long int sqlite_uint64;
303
#endif
304
typedef sqlite_int64 sqlite3_int64;
305
typedef sqlite_uint64 sqlite3_uint64;
306
307
/*
308
** If compiling for a processor that lacks floating point support,
309
** substitute integer for floating-point.
310
*/
311
#ifdef SQLITE_OMIT_FLOATING_POINT
312
# define double sqlite3_int64
313
#endif
314
315
/*
316
** CAPI3REF: Closing A Database Connection
317
** DESTRUCTOR: sqlite3
318
**
319
** ^The sqlite3_close() and sqlite3_close_v2() routines are destructors
320
** for the [sqlite3] object.
321
** ^Calls to sqlite3_close() and sqlite3_close_v2() return [SQLITE_OK] if
322
** the [sqlite3] object is successfully destroyed and all associated
323
** resources are deallocated.
324
**
325
** Ideally, applications should [sqlite3_finalize | finalize] all
326
** [prepared statements], [sqlite3_blob_close | close] all [BLOB handles], and
327
** [sqlite3_backup_finish | finish] all [sqlite3_backup] objects associated
328
** with the [sqlite3] object prior to attempting to close the object.
329
** ^If the database connection is associated with unfinalized prepared
330
** statements, BLOB handlers, and/or unfinished sqlite3_backup objects then
331
** sqlite3_close() will leave the database connection open and return
332
** [SQLITE_BUSY]. ^If sqlite3_close_v2() is called with unfinalized prepared
333
** statements, unclosed BLOB handlers, and/or unfinished sqlite3_backups,
334
** it returns [SQLITE_OK] regardless, but instead of deallocating the database
335
** connection immediately, it marks the database connection as an unusable
336
** "zombie" and makes arrangements to automatically deallocate the database
337
** connection after all prepared statements are finalized, all BLOB handles
338
** are closed, and all backups have finished. The sqlite3_close_v2() interface
339
** is intended for use with host languages that are garbage collected, and
340
** where the order in which destructors are called is arbitrary.
341
**
342
** ^If an [sqlite3] object is destroyed while a transaction is open,
343
** the transaction is automatically rolled back.
344
**
345
** The C parameter to [sqlite3_close(C)] and [sqlite3_close_v2(C)]
346
** must be either a NULL
347
** pointer or an [sqlite3] object pointer obtained
348
** from [sqlite3_open()], [sqlite3_open16()], or
349
** [sqlite3_open_v2()], and not previously closed.
350
** ^Calling sqlite3_close() or sqlite3_close_v2() with a NULL pointer
351
** argument is a harmless no-op.
352
*/
353
SQLITE_API int sqlite3_close(sqlite3*);
354
SQLITE_API int sqlite3_close_v2(sqlite3*);
355
356
/*
357
** The type for a callback function.
358
** This is legacy and deprecated.  It is included for historical
359
** compatibility and is not documented.
360
*/
361
typedef int (*sqlite3_callback)(void*,int,char**, char**);
362
363
/*
364
** CAPI3REF: One-Step Query Execution Interface
365
** METHOD: sqlite3
366
**
367
** The sqlite3_exec() interface is a convenience wrapper around
368
** [sqlite3_prepare_v2()], [sqlite3_step()], and [sqlite3_finalize()],
369
** that allows an application to run multiple statements of SQL
370
** without having to use a lot of C code.
371
**
372
** ^The sqlite3_exec() interface runs zero or more UTF-8 encoded,
373
** semicolon-separate SQL statements passed into its 2nd argument,
374
** in the context of the [database connection] passed in as its 1st
375
** argument.  ^If the callback function of the 3rd argument to
376
** sqlite3_exec() is not NULL, then it is invoked for each result row
377
** coming out of the evaluated SQL statements.  ^The 4th argument to
378
** sqlite3_exec() is relayed through to the 1st argument of each
379
** callback invocation.  ^If the callback pointer to sqlite3_exec()
380
** is NULL, then no callback is ever invoked and result rows are
381
** ignored.
382
**
383
** ^If an error occurs while evaluating the SQL statements passed into
384
** sqlite3_exec(), then execution of the current statement stops and
385
** subsequent statements are skipped.  ^If the 5th parameter to sqlite3_exec()
386
** is not NULL then any error message is written into memory obtained
387
** from [sqlite3_malloc()] and passed back through the 5th parameter.
388
** To avoid memory leaks, the application should invoke [sqlite3_free()]
389
** on error message strings returned through the 5th parameter of
390
** sqlite3_exec() after the error message string is no longer needed.
391
** ^If the 5th parameter to sqlite3_exec() is not NULL and no errors
392
** occur, then sqlite3_exec() sets the pointer in its 5th parameter to
393
** NULL before returning.
394
**
395
** ^If an sqlite3_exec() callback returns non-zero, the sqlite3_exec()
396
** routine returns SQLITE_ABORT without invoking the callback again and
397
** without running any subsequent SQL statements.
398
**
399
** ^The 2nd argument to the sqlite3_exec() callback function is the
400
** number of columns in the result.  ^The 3rd argument to the sqlite3_exec()
401
** callback is an array of pointers to strings obtained as if from
402
** [sqlite3_column_text()], one for each column.  ^If an element of a
403
** result row is NULL then the corresponding string pointer for the
404
** sqlite3_exec() callback is a NULL pointer.  ^The 4th argument to the
405
** sqlite3_exec() callback is an array of pointers to strings where each
406
** entry represents the name of corresponding result column as obtained
407
** from [sqlite3_column_name()].
408
**
409
** ^If the 2nd parameter to sqlite3_exec() is a NULL pointer, a pointer
410
** to an empty string, or a pointer that contains only whitespace and/or
411
** SQL comments, then no SQL statements are evaluated and the database
412
** is not changed.
413
**
414
** Restrictions:
415
**
416
** <ul>
417
** <li> The application must ensure that the 1st parameter to sqlite3_exec()
418
**      is a valid and open [database connection].
419
** <li> The application must not close the [database connection] specified by
420
**      the 1st parameter to sqlite3_exec() while sqlite3_exec() is running.
421
** <li> The application must not modify the SQL statement text passed into
422
**      the 2nd parameter of sqlite3_exec() while sqlite3_exec() is running.
423
** </ul>
424
*/
425
SQLITE_API int sqlite3_exec(
426
  sqlite3*,                                  /* An open database */
427
  const char *sql,                           /* SQL to be evaluated */
428
  int (*callback)(void*,int,char**,char**),  /* Callback function */
429
  void *,                                    /* 1st argument to callback */
430
  char **errmsg                              /* Error msg written here */
431
);
432
433
/*
434
** CAPI3REF: Result Codes
435
** KEYWORDS: {result code definitions}
436
**
437
** Many SQLite functions return an integer result code from the set shown
438
** here in order to indicate success or failure.
439
**
440
** New error codes may be added in future versions of SQLite.
441
**
442
** See also: [extended result code definitions]
443
*/
444
9.00k
#define SQLITE_OK           0   /* Successful result */
445
/* beginning-of-error-codes */
446
50
#define SQLITE_ERROR        1   /* Generic error */
447
0
#define SQLITE_INTERNAL     2   /* Internal logic error in SQLite */
448
50
#define SQLITE_PERM         3   /* Access permission denied */
449
53
#define SQLITE_ABORT        4   /* Callback routine requested an abort */
450
97
#define SQLITE_BUSY         5   /* The database file is locked */
451
75
#define SQLITE_LOCKED       6   /* A table in the database is locked */
452
7
#define SQLITE_NOMEM        7   /* A malloc() failed */
453
58
#define SQLITE_READONLY     8   /* Attempt to write a readonly database */
454
63
#define SQLITE_INTERRUPT    9   /* Operation terminated by sqlite3_interrupt()*/
455
63
#define SQLITE_IOERR       10   /* Some kind of disk I/O error occurred */
456
0
#define SQLITE_CORRUPT     11   /* The database disk image is malformed */
457
0
#define SQLITE_NOTFOUND    12   /* Unknown opcode in sqlite3_file_control() */
458
63
#define SQLITE_FULL        13   /* Insertion failed because database is full */
459
67
#define SQLITE_CANTOPEN    14   /* Unable to open the database file */
460
67
#define SQLITE_PROTOCOL    15   /* Database lock protocol error */
461
67
#define SQLITE_EMPTY       16   /* Internal use only */
462
67
#define SQLITE_SCHEMA      17   /* The database schema changed */
463
9
#define SQLITE_TOOBIG      18   /* String or BLOB exceeds size limit */
464
10
#define SQLITE_CONSTRAINT  19   /* Abort due to constraint violation */
465
10
#define SQLITE_MISMATCH    20   /* Data type mismatch */
466
46
#define SQLITE_MISUSE      21   /* Library used incorrectly */
467
#define SQLITE_NOLFS       22   /* Uses OS features not supported on host */
468
#define SQLITE_AUTH        23   /* Authorization denied */
469
#define SQLITE_FORMAT      24   /* Not used */
470
0
#define SQLITE_RANGE       25   /* 2nd parameter to sqlite3_bind out of range */
471
#define SQLITE_NOTADB      26   /* File opened that is not a database file */
472
#define SQLITE_NOTICE      27   /* Notifications from sqlite3_log() */
473
#define SQLITE_WARNING     28   /* Warnings from sqlite3_log() */
474
1.11k
#define SQLITE_ROW         100  /* sqlite3_step() has another row ready */
475
6.13k
#define SQLITE_DONE        101  /* sqlite3_step() has finished executing */
476
/* end-of-error-codes */
477
478
/*
479
** CAPI3REF: Extended Result Codes
480
** KEYWORDS: {extended result code definitions}
481
**
482
** In its default configuration, SQLite API routines return one of 30 integer
483
** [result codes].  However, experience has shown that many of
484
** these result codes are too coarse-grained.  They do not provide as
485
** much information about problems as programmers might like.  In an effort to
486
** address this, newer versions of SQLite (version 3.3.8 [dateof:3.3.8]
487
** and later) include
488
** support for additional result codes that provide more detailed information
489
** about errors. These [extended result codes] are enabled or disabled
490
** on a per database connection basis using the
491
** [sqlite3_extended_result_codes()] API.  Or, the extended code for
492
** the most recent error can be obtained using
493
** [sqlite3_extended_errcode()].
494
*/
495
#define SQLITE_ERROR_MISSING_COLLSEQ   (SQLITE_ERROR | (1<<8))
496
#define SQLITE_ERROR_RETRY             (SQLITE_ERROR | (2<<8))
497
#define SQLITE_ERROR_SNAPSHOT          (SQLITE_ERROR | (3<<8))
498
#define SQLITE_IOERR_READ              (SQLITE_IOERR | (1<<8))
499
#define SQLITE_IOERR_SHORT_READ        (SQLITE_IOERR | (2<<8))
500
#define SQLITE_IOERR_WRITE             (SQLITE_IOERR | (3<<8))
501
#define SQLITE_IOERR_FSYNC             (SQLITE_IOERR | (4<<8))
502
#define SQLITE_IOERR_DIR_FSYNC         (SQLITE_IOERR | (5<<8))
503
#define SQLITE_IOERR_TRUNCATE          (SQLITE_IOERR | (6<<8))
504
#define SQLITE_IOERR_FSTAT             (SQLITE_IOERR | (7<<8))
505
#define SQLITE_IOERR_UNLOCK            (SQLITE_IOERR | (8<<8))
506
#define SQLITE_IOERR_RDLOCK            (SQLITE_IOERR | (9<<8))
507
#define SQLITE_IOERR_DELETE            (SQLITE_IOERR | (10<<8))
508
#define SQLITE_IOERR_BLOCKED           (SQLITE_IOERR | (11<<8))
509
#define SQLITE_IOERR_NOMEM             (SQLITE_IOERR | (12<<8))
510
#define SQLITE_IOERR_ACCESS            (SQLITE_IOERR | (13<<8))
511
#define SQLITE_IOERR_CHECKRESERVEDLOCK (SQLITE_IOERR | (14<<8))
512
#define SQLITE_IOERR_LOCK              (SQLITE_IOERR | (15<<8))
513
#define SQLITE_IOERR_CLOSE             (SQLITE_IOERR | (16<<8))
514
#define SQLITE_IOERR_DIR_CLOSE         (SQLITE_IOERR | (17<<8))
515
#define SQLITE_IOERR_SHMOPEN           (SQLITE_IOERR | (18<<8))
516
#define SQLITE_IOERR_SHMSIZE           (SQLITE_IOERR | (19<<8))
517
#define SQLITE_IOERR_SHMLOCK           (SQLITE_IOERR | (20<<8))
518
#define SQLITE_IOERR_SHMMAP            (SQLITE_IOERR | (21<<8))
519
#define SQLITE_IOERR_SEEK              (SQLITE_IOERR | (22<<8))
520
#define SQLITE_IOERR_DELETE_NOENT      (SQLITE_IOERR | (23<<8))
521
#define SQLITE_IOERR_MMAP              (SQLITE_IOERR | (24<<8))
522
#define SQLITE_IOERR_GETTEMPPATH       (SQLITE_IOERR | (25<<8))
523
#define SQLITE_IOERR_CONVPATH          (SQLITE_IOERR | (26<<8))
524
#define SQLITE_IOERR_VNODE             (SQLITE_IOERR | (27<<8))
525
#define SQLITE_IOERR_AUTH              (SQLITE_IOERR | (28<<8))
526
#define SQLITE_IOERR_BEGIN_ATOMIC      (SQLITE_IOERR | (29<<8))
527
#define SQLITE_IOERR_COMMIT_ATOMIC     (SQLITE_IOERR | (30<<8))
528
#define SQLITE_IOERR_ROLLBACK_ATOMIC   (SQLITE_IOERR | (31<<8))
529
#define SQLITE_IOERR_DATA              (SQLITE_IOERR | (32<<8))
530
#define SQLITE_IOERR_CORRUPTFS         (SQLITE_IOERR | (33<<8))
531
#define SQLITE_LOCKED_SHAREDCACHE      (SQLITE_LOCKED |  (1<<8))
532
#define SQLITE_LOCKED_VTAB             (SQLITE_LOCKED |  (2<<8))
533
#define SQLITE_BUSY_RECOVERY           (SQLITE_BUSY   |  (1<<8))
534
#define SQLITE_BUSY_SNAPSHOT           (SQLITE_BUSY   |  (2<<8))
535
#define SQLITE_BUSY_TIMEOUT            (SQLITE_BUSY   |  (3<<8))
536
#define SQLITE_CANTOPEN_NOTEMPDIR      (SQLITE_CANTOPEN | (1<<8))
537
#define SQLITE_CANTOPEN_ISDIR          (SQLITE_CANTOPEN | (2<<8))
538
#define SQLITE_CANTOPEN_FULLPATH       (SQLITE_CANTOPEN | (3<<8))
539
#define SQLITE_CANTOPEN_CONVPATH       (SQLITE_CANTOPEN | (4<<8))
540
#define SQLITE_CANTOPEN_DIRTYWAL       (SQLITE_CANTOPEN | (5<<8)) /* Not Used */
541
#define SQLITE_CANTOPEN_SYMLINK        (SQLITE_CANTOPEN | (6<<8))
542
#define SQLITE_CORRUPT_VTAB            (SQLITE_CORRUPT | (1<<8))
543
#define SQLITE_CORRUPT_SEQUENCE        (SQLITE_CORRUPT | (2<<8))
544
#define SQLITE_CORRUPT_INDEX           (SQLITE_CORRUPT | (3<<8))
545
#define SQLITE_READONLY_RECOVERY       (SQLITE_READONLY | (1<<8))
546
#define SQLITE_READONLY_CANTLOCK       (SQLITE_READONLY | (2<<8))
547
#define SQLITE_READONLY_ROLLBACK       (SQLITE_READONLY | (3<<8))
548
#define SQLITE_READONLY_DBMOVED        (SQLITE_READONLY | (4<<8))
549
#define SQLITE_READONLY_CANTINIT       (SQLITE_READONLY | (5<<8))
550
#define SQLITE_READONLY_DIRECTORY      (SQLITE_READONLY | (6<<8))
551
#define SQLITE_ABORT_ROLLBACK          (SQLITE_ABORT | (2<<8))
552
#define SQLITE_CONSTRAINT_CHECK        (SQLITE_CONSTRAINT | (1<<8))
553
#define SQLITE_CONSTRAINT_COMMITHOOK   (SQLITE_CONSTRAINT | (2<<8))
554
#define SQLITE_CONSTRAINT_FOREIGNKEY   (SQLITE_CONSTRAINT | (3<<8))
555
#define SQLITE_CONSTRAINT_FUNCTION     (SQLITE_CONSTRAINT | (4<<8))
556
#define SQLITE_CONSTRAINT_NOTNULL      (SQLITE_CONSTRAINT | (5<<8))
557
#define SQLITE_CONSTRAINT_PRIMARYKEY   (SQLITE_CONSTRAINT | (6<<8))
558
#define SQLITE_CONSTRAINT_TRIGGER      (SQLITE_CONSTRAINT | (7<<8))
559
#define SQLITE_CONSTRAINT_UNIQUE       (SQLITE_CONSTRAINT | (8<<8))
560
#define SQLITE_CONSTRAINT_VTAB         (SQLITE_CONSTRAINT | (9<<8))
561
#define SQLITE_CONSTRAINT_ROWID        (SQLITE_CONSTRAINT |(10<<8))
562
#define SQLITE_CONSTRAINT_PINNED       (SQLITE_CONSTRAINT |(11<<8))
563
#define SQLITE_CONSTRAINT_DATATYPE     (SQLITE_CONSTRAINT |(12<<8))
564
#define SQLITE_NOTICE_RECOVER_WAL      (SQLITE_NOTICE | (1<<8))
565
#define SQLITE_NOTICE_RECOVER_ROLLBACK (SQLITE_NOTICE | (2<<8))
566
#define SQLITE_WARNING_AUTOINDEX       (SQLITE_WARNING | (1<<8))
567
#define SQLITE_AUTH_USER               (SQLITE_AUTH | (1<<8))
568
#define SQLITE_OK_LOAD_PERMANENTLY     (SQLITE_OK | (1<<8))
569
#define SQLITE_OK_SYMLINK              (SQLITE_OK | (2<<8)) /* internal use only */
570
571
/*
572
** CAPI3REF: Flags For File Open Operations
573
**
574
** These bit values are intended for use in the
575
** 3rd parameter to the [sqlite3_open_v2()] interface and
576
** in the 4th parameter to the [sqlite3_vfs.xOpen] method.
577
**
578
** Only those flags marked as "Ok for sqlite3_open_v2()" may be
579
** used as the third argument to the [sqlite3_open_v2()] interface.
580
** The other flags have historically been ignored by sqlite3_open_v2(),
581
** though future versions of SQLite might change so that an error is
582
** raised if any of the disallowed bits are passed into sqlite3_open_v2().
583
** Applications should not depend on the historical behavior.
584
**
585
** Note in particular that passing the SQLITE_OPEN_EXCLUSIVE flag into
586
** [sqlite3_open_v2()] does *not* cause the underlying database file
587
** to be opened using O_EXCL.  Passing SQLITE_OPEN_EXCLUSIVE into
588
** [sqlite3_open_v2()] has historically be a no-op and might become an
589
** error in future versions of SQLite.
590
*/
591
#define SQLITE_OPEN_READONLY         0x00000001  /* Ok for sqlite3_open_v2() */
592
490
#define SQLITE_OPEN_READWRITE        0x00000002  /* Ok for sqlite3_open_v2() */
593
490
#define SQLITE_OPEN_CREATE           0x00000004  /* Ok for sqlite3_open_v2() */
594
#define SQLITE_OPEN_DELETEONCLOSE    0x00000008  /* VFS only */
595
#define SQLITE_OPEN_EXCLUSIVE        0x00000010  /* VFS only */
596
#define SQLITE_OPEN_AUTOPROXY        0x00000020  /* VFS only */
597
4
#define SQLITE_OPEN_URI              0x00000040  /* Ok for sqlite3_open_v2() */
598
#define SQLITE_OPEN_MEMORY           0x00000080  /* Ok for sqlite3_open_v2() */
599
#define SQLITE_OPEN_MAIN_DB          0x00000100  /* VFS only */
600
#define SQLITE_OPEN_TEMP_DB          0x00000200  /* VFS only */
601
#define SQLITE_OPEN_TRANSIENT_DB     0x00000400  /* VFS only */
602
#define SQLITE_OPEN_MAIN_JOURNAL     0x00000800  /* VFS only */
603
#define SQLITE_OPEN_TEMP_JOURNAL     0x00001000  /* VFS only */
604
#define SQLITE_OPEN_SUBJOURNAL       0x00002000  /* VFS only */
605
#define SQLITE_OPEN_SUPER_JOURNAL    0x00004000  /* VFS only */
606
#define SQLITE_OPEN_NOMUTEX          0x00008000  /* Ok for sqlite3_open_v2() */
607
#define SQLITE_OPEN_FULLMUTEX        0x00010000  /* Ok for sqlite3_open_v2() */
608
#define SQLITE_OPEN_SHAREDCACHE      0x00020000  /* Ok for sqlite3_open_v2() */
609
#define SQLITE_OPEN_PRIVATECACHE     0x00040000  /* Ok for sqlite3_open_v2() */
610
#define SQLITE_OPEN_WAL              0x00080000  /* VFS only */
611
#define SQLITE_OPEN_NOFOLLOW         0x01000000  /* Ok for sqlite3_open_v2() */
612
#define SQLITE_OPEN_EXRESCODE        0x02000000  /* Extended result codes */
613
614
/* Reserved:                         0x00F00000 */
615
/* Legacy compatibility: */
616
#define SQLITE_OPEN_MASTER_JOURNAL   0x00004000  /* VFS only */
617
618
619
/*
620
** CAPI3REF: Device Characteristics
621
**
622
** The xDeviceCharacteristics method of the [sqlite3_io_methods]
623
** object returns an integer which is a vector of these
624
** bit values expressing I/O characteristics of the mass storage
625
** device that holds the file that the [sqlite3_io_methods]
626
** refers to.
627
**
628
** The SQLITE_IOCAP_ATOMIC property means that all writes of
629
** any size are atomic.  The SQLITE_IOCAP_ATOMICnnn values
630
** mean that writes of blocks that are nnn bytes in size and
631
** are aligned to an address which is an integer multiple of
632
** nnn are atomic.  The SQLITE_IOCAP_SAFE_APPEND value means
633
** that when data is appended to a file, the data is appended
634
** first then the size of the file is extended, never the other
635
** way around.  The SQLITE_IOCAP_SEQUENTIAL property means that
636
** information is written to disk in the same order as calls
637
** to xWrite().  The SQLITE_IOCAP_POWERSAFE_OVERWRITE property means that
638
** after reboot following a crash or power loss, the only bytes in a
639
** file that were written at the application level might have changed
640
** and that adjacent bytes, even bytes within the same sector are
641
** guaranteed to be unchanged.  The SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN
642
** flag indicates that a file cannot be deleted when open.  The
643
** SQLITE_IOCAP_IMMUTABLE flag indicates that the file is on
644
** read-only media and cannot be changed even by processes with
645
** elevated privileges.
646
**
647
** The SQLITE_IOCAP_BATCH_ATOMIC property means that the underlying
648
** filesystem supports doing multiple write operations atomically when those
649
** write operations are bracketed by [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE] and
650
** [SQLITE_FCNTL_COMMIT_ATOMIC_WRITE].
651
*/
652
#define SQLITE_IOCAP_ATOMIC                 0x00000001
653
#define SQLITE_IOCAP_ATOMIC512              0x00000002
654
#define SQLITE_IOCAP_ATOMIC1K               0x00000004
655
#define SQLITE_IOCAP_ATOMIC2K               0x00000008
656
#define SQLITE_IOCAP_ATOMIC4K               0x00000010
657
#define SQLITE_IOCAP_ATOMIC8K               0x00000020
658
#define SQLITE_IOCAP_ATOMIC16K              0x00000040
659
#define SQLITE_IOCAP_ATOMIC32K              0x00000080
660
#define SQLITE_IOCAP_ATOMIC64K              0x00000100
661
#define SQLITE_IOCAP_SAFE_APPEND            0x00000200
662
#define SQLITE_IOCAP_SEQUENTIAL             0x00000400
663
#define SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN  0x00000800
664
#define SQLITE_IOCAP_POWERSAFE_OVERWRITE    0x00001000
665
#define SQLITE_IOCAP_IMMUTABLE              0x00002000
666
#define SQLITE_IOCAP_BATCH_ATOMIC           0x00004000
667
668
/*
669
** CAPI3REF: File Locking Levels
670
**
671
** SQLite uses one of these integer values as the second
672
** argument to calls it makes to the xLock() and xUnlock() methods
673
** of an [sqlite3_io_methods] object.
674
*/
675
#define SQLITE_LOCK_NONE          0
676
#define SQLITE_LOCK_SHARED        1
677
#define SQLITE_LOCK_RESERVED      2
678
#define SQLITE_LOCK_PENDING       3
679
#define SQLITE_LOCK_EXCLUSIVE     4
680
681
/*
682
** CAPI3REF: Synchronization Type Flags
683
**
684
** When SQLite invokes the xSync() method of an
685
** [sqlite3_io_methods] object it uses a combination of
686
** these integer values as the second argument.
687
**
688
** When the SQLITE_SYNC_DATAONLY flag is used, it means that the
689
** sync operation only needs to flush data to mass storage.  Inode
690
** information need not be flushed. If the lower four bits of the flag
691
** equal SQLITE_SYNC_NORMAL, that means to use normal fsync() semantics.
692
** If the lower four bits equal SQLITE_SYNC_FULL, that means
693
** to use Mac OS X style fullsync instead of fsync().
694
**
695
** Do not confuse the SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL flags
696
** with the [PRAGMA synchronous]=NORMAL and [PRAGMA synchronous]=FULL
697
** settings.  The [synchronous pragma] determines when calls to the
698
** xSync VFS method occur and applies uniformly across all platforms.
699
** The SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL flags determine how
700
** energetic or rigorous or forceful the sync operations are and
701
** only make a difference on Mac OSX for the default SQLite code.
702
** (Third-party VFS implementations might also make the distinction
703
** between SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL, but among the
704
** operating systems natively supported by SQLite, only Mac OSX
705
** cares about the difference.)
706
*/
707
#define SQLITE_SYNC_NORMAL        0x00002
708
#define SQLITE_SYNC_FULL          0x00003
709
#define SQLITE_SYNC_DATAONLY      0x00010
710
711
/*
712
** CAPI3REF: OS Interface Open File Handle
713
**
714
** An [sqlite3_file] object represents an open file in the
715
** [sqlite3_vfs | OS interface layer].  Individual OS interface
716
** implementations will
717
** want to subclass this object by appending additional fields
718
** for their own use.  The pMethods entry is a pointer to an
719
** [sqlite3_io_methods] object that defines methods for performing
720
** I/O operations on the open file.
721
*/
722
typedef struct sqlite3_file sqlite3_file;
723
struct sqlite3_file {
724
  const struct sqlite3_io_methods *pMethods;  /* Methods for an open file */
725
};
726
727
/*
728
** CAPI3REF: OS Interface File Virtual Methods Object
729
**
730
** Every file opened by the [sqlite3_vfs.xOpen] method populates an
731
** [sqlite3_file] object (or, more commonly, a subclass of the
732
** [sqlite3_file] object) with a pointer to an instance of this object.
733
** This object defines the methods used to perform various operations
734
** against the open file represented by the [sqlite3_file] object.
735
**
736
** If the [sqlite3_vfs.xOpen] method sets the sqlite3_file.pMethods element
737
** to a non-NULL pointer, then the sqlite3_io_methods.xClose method
738
** may be invoked even if the [sqlite3_vfs.xOpen] reported that it failed.  The
739
** only way to prevent a call to xClose following a failed [sqlite3_vfs.xOpen]
740
** is for the [sqlite3_vfs.xOpen] to set the sqlite3_file.pMethods element
741
** to NULL.
742
**
743
** The flags argument to xSync may be one of [SQLITE_SYNC_NORMAL] or
744
** [SQLITE_SYNC_FULL].  The first choice is the normal fsync().
745
** The second choice is a Mac OS X style fullsync.  The [SQLITE_SYNC_DATAONLY]
746
** flag may be ORed in to indicate that only the data of the file
747
** and not its inode needs to be synced.
748
**
749
** The integer values to xLock() and xUnlock() are one of
750
** <ul>
751
** <li> [SQLITE_LOCK_NONE],
752
** <li> [SQLITE_LOCK_SHARED],
753
** <li> [SQLITE_LOCK_RESERVED],
754
** <li> [SQLITE_LOCK_PENDING], or
755
** <li> [SQLITE_LOCK_EXCLUSIVE].
756
** </ul>
757
** xLock() increases the lock. xUnlock() decreases the lock.
758
** The xCheckReservedLock() method checks whether any database connection,
759
** either in this process or in some other process, is holding a RESERVED,
760
** PENDING, or EXCLUSIVE lock on the file.  It returns true
761
** if such a lock exists and false otherwise.
762
**
763
** The xFileControl() method is a generic interface that allows custom
764
** VFS implementations to directly control an open file using the
765
** [sqlite3_file_control()] interface.  The second "op" argument is an
766
** integer opcode.  The third argument is a generic pointer intended to
767
** point to a structure that may contain arguments or space in which to
768
** write return values.  Potential uses for xFileControl() might be
769
** functions to enable blocking locks with timeouts, to change the
770
** locking strategy (for example to use dot-file locks), to inquire
771
** about the status of a lock, or to break stale locks.  The SQLite
772
** core reserves all opcodes less than 100 for its own use.
773
** A [file control opcodes | list of opcodes] less than 100 is available.
774
** Applications that define a custom xFileControl method should use opcodes
775
** greater than 100 to avoid conflicts.  VFS implementations should
776
** return [SQLITE_NOTFOUND] for file control opcodes that they do not
777
** recognize.
778
**
779
** The xSectorSize() method returns the sector size of the
780
** device that underlies the file.  The sector size is the
781
** minimum write that can be performed without disturbing
782
** other bytes in the file.  The xDeviceCharacteristics()
783
** method returns a bit vector describing behaviors of the
784
** underlying device:
785
**
786
** <ul>
787
** <li> [SQLITE_IOCAP_ATOMIC]
788
** <li> [SQLITE_IOCAP_ATOMIC512]
789
** <li> [SQLITE_IOCAP_ATOMIC1K]
790
** <li> [SQLITE_IOCAP_ATOMIC2K]
791
** <li> [SQLITE_IOCAP_ATOMIC4K]
792
** <li> [SQLITE_IOCAP_ATOMIC8K]
793
** <li> [SQLITE_IOCAP_ATOMIC16K]
794
** <li> [SQLITE_IOCAP_ATOMIC32K]
795
** <li> [SQLITE_IOCAP_ATOMIC64K]
796
** <li> [SQLITE_IOCAP_SAFE_APPEND]
797
** <li> [SQLITE_IOCAP_SEQUENTIAL]
798
** <li> [SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN]
799
** <li> [SQLITE_IOCAP_POWERSAFE_OVERWRITE]
800
** <li> [SQLITE_IOCAP_IMMUTABLE]
801
** <li> [SQLITE_IOCAP_BATCH_ATOMIC]
802
** </ul>
803
**
804
** The SQLITE_IOCAP_ATOMIC property means that all writes of
805
** any size are atomic.  The SQLITE_IOCAP_ATOMICnnn values
806
** mean that writes of blocks that are nnn bytes in size and
807
** are aligned to an address which is an integer multiple of
808
** nnn are atomic.  The SQLITE_IOCAP_SAFE_APPEND value means
809
** that when data is appended to a file, the data is appended
810
** first then the size of the file is extended, never the other
811
** way around.  The SQLITE_IOCAP_SEQUENTIAL property means that
812
** information is written to disk in the same order as calls
813
** to xWrite().
814
**
815
** If xRead() returns SQLITE_IOERR_SHORT_READ it must also fill
816
** in the unread portions of the buffer with zeros.  A VFS that
817
** fails to zero-fill short reads might seem to work.  However,
818
** failure to zero-fill short reads will eventually lead to
819
** database corruption.
820
*/
821
typedef struct sqlite3_io_methods sqlite3_io_methods;
822
struct sqlite3_io_methods {
823
  int iVersion;
824
  int (*xClose)(sqlite3_file*);
825
  int (*xRead)(sqlite3_file*, void*, int iAmt, sqlite3_int64 iOfst);
826
  int (*xWrite)(sqlite3_file*, const void*, int iAmt, sqlite3_int64 iOfst);
827
  int (*xTruncate)(sqlite3_file*, sqlite3_int64 size);
828
  int (*xSync)(sqlite3_file*, int flags);
829
  int (*xFileSize)(sqlite3_file*, sqlite3_int64 *pSize);
830
  int (*xLock)(sqlite3_file*, int);
831
  int (*xUnlock)(sqlite3_file*, int);
832
  int (*xCheckReservedLock)(sqlite3_file*, int *pResOut);
833
  int (*xFileControl)(sqlite3_file*, int op, void *pArg);
834
  int (*xSectorSize)(sqlite3_file*);
835
  int (*xDeviceCharacteristics)(sqlite3_file*);
836
  /* Methods above are valid for version 1 */
837
  int (*xShmMap)(sqlite3_file*, int iPg, int pgsz, int, void volatile**);
838
  int (*xShmLock)(sqlite3_file*, int offset, int n, int flags);
839
  void (*xShmBarrier)(sqlite3_file*);
840
  int (*xShmUnmap)(sqlite3_file*, int deleteFlag);
841
  /* Methods above are valid for version 2 */
842
  int (*xFetch)(sqlite3_file*, sqlite3_int64 iOfst, int iAmt, void **pp);
843
  int (*xUnfetch)(sqlite3_file*, sqlite3_int64 iOfst, void *p);
844
  /* Methods above are valid for version 3 */
845
  /* Additional methods may be added in future releases */
846
};
847
848
/*
849
** CAPI3REF: Standard File Control Opcodes
850
** KEYWORDS: {file control opcodes} {file control opcode}
851
**
852
** These integer constants are opcodes for the xFileControl method
853
** of the [sqlite3_io_methods] object and for the [sqlite3_file_control()]
854
** interface.
855
**
856
** <ul>
857
** <li>[[SQLITE_FCNTL_LOCKSTATE]]
858
** The [SQLITE_FCNTL_LOCKSTATE] opcode is used for debugging.  This
859
** opcode causes the xFileControl method to write the current state of
860
** the lock (one of [SQLITE_LOCK_NONE], [SQLITE_LOCK_SHARED],
861
** [SQLITE_LOCK_RESERVED], [SQLITE_LOCK_PENDING], or [SQLITE_LOCK_EXCLUSIVE])
862
** into an integer that the pArg argument points to. This capability
863
** is used during testing and is only available when the SQLITE_TEST
864
** compile-time option is used.
865
**
866
** <li>[[SQLITE_FCNTL_SIZE_HINT]]
867
** The [SQLITE_FCNTL_SIZE_HINT] opcode is used by SQLite to give the VFS
868
** layer a hint of how large the database file will grow to be during the
869
** current transaction.  This hint is not guaranteed to be accurate but it
870
** is often close.  The underlying VFS might choose to preallocate database
871
** file space based on this hint in order to help writes to the database
872
** file run faster.
873
**
874
** <li>[[SQLITE_FCNTL_SIZE_LIMIT]]
875
** The [SQLITE_FCNTL_SIZE_LIMIT] opcode is used by in-memory VFS that
876
** implements [sqlite3_deserialize()] to set an upper bound on the size
877
** of the in-memory database.  The argument is a pointer to a [sqlite3_int64].
878
** If the integer pointed to is negative, then it is filled in with the
879
** current limit.  Otherwise the limit is set to the larger of the value
880
** of the integer pointed to and the current database size.  The integer
881
** pointed to is set to the new limit.
882
**
883
** <li>[[SQLITE_FCNTL_CHUNK_SIZE]]
884
** The [SQLITE_FCNTL_CHUNK_SIZE] opcode is used to request that the VFS
885
** extends and truncates the database file in chunks of a size specified
886
** by the user. The fourth argument to [sqlite3_file_control()] should
887
** point to an integer (type int) containing the new chunk-size to use
888
** for the nominated database. Allocating database file space in large
889
** chunks (say 1MB at a time), may reduce file-system fragmentation and
890
** improve performance on some systems.
891
**
892
** <li>[[SQLITE_FCNTL_FILE_POINTER]]
893
** The [SQLITE_FCNTL_FILE_POINTER] opcode is used to obtain a pointer
894
** to the [sqlite3_file] object associated with a particular database
895
** connection.  See also [SQLITE_FCNTL_JOURNAL_POINTER].
896
**
897
** <li>[[SQLITE_FCNTL_JOURNAL_POINTER]]
898
** The [SQLITE_FCNTL_JOURNAL_POINTER] opcode is used to obtain a pointer
899
** to the [sqlite3_file] object associated with the journal file (either
900
** the [rollback journal] or the [write-ahead log]) for a particular database
901
** connection.  See also [SQLITE_FCNTL_FILE_POINTER].
902
**
903
** <li>[[SQLITE_FCNTL_SYNC_OMITTED]]
904
** No longer in use.
905
**
906
** <li>[[SQLITE_FCNTL_SYNC]]
907
** The [SQLITE_FCNTL_SYNC] opcode is generated internally by SQLite and
908
** sent to the VFS immediately before the xSync method is invoked on a
909
** database file descriptor. Or, if the xSync method is not invoked
910
** because the user has configured SQLite with
911
** [PRAGMA synchronous | PRAGMA synchronous=OFF] it is invoked in place
912
** of the xSync method. In most cases, the pointer argument passed with
913
** this file-control is NULL. However, if the database file is being synced
914
** as part of a multi-database commit, the argument points to a nul-terminated
915
** string containing the transactions super-journal file name. VFSes that
916
** do not need this signal should silently ignore this opcode. Applications
917
** should not call [sqlite3_file_control()] with this opcode as doing so may
918
** disrupt the operation of the specialized VFSes that do require it.
919
**
920
** <li>[[SQLITE_FCNTL_COMMIT_PHASETWO]]
921
** The [SQLITE_FCNTL_COMMIT_PHASETWO] opcode is generated internally by SQLite
922
** and sent to the VFS after a transaction has been committed immediately
923
** but before the database is unlocked. VFSes that do not need this signal
924
** should silently ignore this opcode. Applications should not call
925
** [sqlite3_file_control()] with this opcode as doing so may disrupt the
926
** operation of the specialized VFSes that do require it.
927
**
928
** <li>[[SQLITE_FCNTL_WIN32_AV_RETRY]]
929
** ^The [SQLITE_FCNTL_WIN32_AV_RETRY] opcode is used to configure automatic
930
** retry counts and intervals for certain disk I/O operations for the
931
** windows [VFS] in order to provide robustness in the presence of
932
** anti-virus programs.  By default, the windows VFS will retry file read,
933
** file write, and file delete operations up to 10 times, with a delay
934
** of 25 milliseconds before the first retry and with the delay increasing
935
** by an additional 25 milliseconds with each subsequent retry.  This
936
** opcode allows these two values (10 retries and 25 milliseconds of delay)
937
** to be adjusted.  The values are changed for all database connections
938
** within the same process.  The argument is a pointer to an array of two
939
** integers where the first integer is the new retry count and the second
940
** integer is the delay.  If either integer is negative, then the setting
941
** is not changed but instead the prior value of that setting is written
942
** into the array entry, allowing the current retry settings to be
943
** interrogated.  The zDbName parameter is ignored.
944
**
945
** <li>[[SQLITE_FCNTL_PERSIST_WAL]]
946
** ^The [SQLITE_FCNTL_PERSIST_WAL] opcode is used to set or query the
947
** persistent [WAL | Write Ahead Log] setting.  By default, the auxiliary
948
** write ahead log ([WAL file]) and shared memory
949
** files used for transaction control
950
** are automatically deleted when the latest connection to the database
951
** closes.  Setting persistent WAL mode causes those files to persist after
952
** close.  Persisting the files is useful when other processes that do not
953
** have write permission on the directory containing the database file want
954
** to read the database file, as the WAL and shared memory files must exist
955
** in order for the database to be readable.  The fourth parameter to
956
** [sqlite3_file_control()] for this opcode should be a pointer to an integer.
957
** That integer is 0 to disable persistent WAL mode or 1 to enable persistent
958
** WAL mode.  If the integer is -1, then it is overwritten with the current
959
** WAL persistence setting.
960
**
961
** <li>[[SQLITE_FCNTL_POWERSAFE_OVERWRITE]]
962
** ^The [SQLITE_FCNTL_POWERSAFE_OVERWRITE] opcode is used to set or query the
963
** persistent "powersafe-overwrite" or "PSOW" setting.  The PSOW setting
964
** determines the [SQLITE_IOCAP_POWERSAFE_OVERWRITE] bit of the
965
** xDeviceCharacteristics methods. The fourth parameter to
966
** [sqlite3_file_control()] for this opcode should be a pointer to an integer.
967
** That integer is 0 to disable zero-damage mode or 1 to enable zero-damage
968
** mode.  If the integer is -1, then it is overwritten with the current
969
** zero-damage mode setting.
970
**
971
** <li>[[SQLITE_FCNTL_OVERWRITE]]
972
** ^The [SQLITE_FCNTL_OVERWRITE] opcode is invoked by SQLite after opening
973
** a write transaction to indicate that, unless it is rolled back for some
974
** reason, the entire database file will be overwritten by the current
975
** transaction. This is used by VACUUM operations.
976
**
977
** <li>[[SQLITE_FCNTL_VFSNAME]]
978
** ^The [SQLITE_FCNTL_VFSNAME] opcode can be used to obtain the names of
979
** all [VFSes] in the VFS stack.  The names are of all VFS shims and the
980
** final bottom-level VFS are written into memory obtained from
981
** [sqlite3_malloc()] and the result is stored in the char* variable
982
** that the fourth parameter of [sqlite3_file_control()] points to.
983
** The caller is responsible for freeing the memory when done.  As with
984
** all file-control actions, there is no guarantee that this will actually
985
** do anything.  Callers should initialize the char* variable to a NULL
986
** pointer in case this file-control is not implemented.  This file-control
987
** is intended for diagnostic use only.
988
**
989
** <li>[[SQLITE_FCNTL_VFS_POINTER]]
990
** ^The [SQLITE_FCNTL_VFS_POINTER] opcode finds a pointer to the top-level
991
** [VFSes] currently in use.  ^(The argument X in
992
** sqlite3_file_control(db,SQLITE_FCNTL_VFS_POINTER,X) must be
993
** of type "[sqlite3_vfs] **".  This opcodes will set *X
994
** to a pointer to the top-level VFS.)^
995
** ^When there are multiple VFS shims in the stack, this opcode finds the
996
** upper-most shim only.
997
**
998
** <li>[[SQLITE_FCNTL_PRAGMA]]
999
** ^Whenever a [PRAGMA] statement is parsed, an [SQLITE_FCNTL_PRAGMA]
1000
** file control is sent to the open [sqlite3_file] object corresponding
1001
** to the database file to which the pragma statement refers. ^The argument
1002
** to the [SQLITE_FCNTL_PRAGMA] file control is an array of
1003
** pointers to strings (char**) in which the second element of the array
1004
** is the name of the pragma and the third element is the argument to the
1005
** pragma or NULL if the pragma has no argument.  ^The handler for an
1006
** [SQLITE_FCNTL_PRAGMA] file control can optionally make the first element
1007
** of the char** argument point to a string obtained from [sqlite3_mprintf()]
1008
** or the equivalent and that string will become the result of the pragma or
1009
** the error message if the pragma fails. ^If the
1010
** [SQLITE_FCNTL_PRAGMA] file control returns [SQLITE_NOTFOUND], then normal
1011
** [PRAGMA] processing continues.  ^If the [SQLITE_FCNTL_PRAGMA]
1012
** file control returns [SQLITE_OK], then the parser assumes that the
1013
** VFS has handled the PRAGMA itself and the parser generates a no-op
1014
** prepared statement if result string is NULL, or that returns a copy
1015
** of the result string if the string is non-NULL.
1016
** ^If the [SQLITE_FCNTL_PRAGMA] file control returns
1017
** any result code other than [SQLITE_OK] or [SQLITE_NOTFOUND], that means
1018
** that the VFS encountered an error while handling the [PRAGMA] and the
1019
** compilation of the PRAGMA fails with an error.  ^The [SQLITE_FCNTL_PRAGMA]
1020
** file control occurs at the beginning of pragma statement analysis and so
1021
** it is able to override built-in [PRAGMA] statements.
1022
**
1023
** <li>[[SQLITE_FCNTL_BUSYHANDLER]]
1024
** ^The [SQLITE_FCNTL_BUSYHANDLER]
1025
** file-control may be invoked by SQLite on the database file handle
1026
** shortly after it is opened in order to provide a custom VFS with access
1027
** to the connection's busy-handler callback. The argument is of type (void**)
1028
** - an array of two (void *) values. The first (void *) actually points
1029
** to a function of type (int (*)(void *)). In order to invoke the connection's
1030
** busy-handler, this function should be invoked with the second (void *) in
1031
** the array as the only argument. If it returns non-zero, then the operation
1032
** should be retried. If it returns zero, the custom VFS should abandon the
1033
** current operation.
1034
**
1035
** <li>[[SQLITE_FCNTL_TEMPFILENAME]]
1036
** ^Applications can invoke the [SQLITE_FCNTL_TEMPFILENAME] file-control
1037
** to have SQLite generate a
1038
** temporary filename using the same algorithm that is followed to generate
1039
** temporary filenames for TEMP tables and other internal uses.  The
1040
** argument should be a char** which will be filled with the filename
1041
** written into memory obtained from [sqlite3_malloc()].  The caller should
1042
** invoke [sqlite3_free()] on the result to avoid a memory leak.
1043
**
1044
** <li>[[SQLITE_FCNTL_MMAP_SIZE]]
1045
** The [SQLITE_FCNTL_MMAP_SIZE] file control is used to query or set the
1046
** maximum number of bytes that will be used for memory-mapped I/O.
1047
** The argument is a pointer to a value of type sqlite3_int64 that
1048
** is an advisory maximum number of bytes in the file to memory map.  The
1049
** pointer is overwritten with the old value.  The limit is not changed if
1050
** the value originally pointed to is negative, and so the current limit
1051
** can be queried by passing in a pointer to a negative number.  This
1052
** file-control is used internally to implement [PRAGMA mmap_size].
1053
**
1054
** <li>[[SQLITE_FCNTL_TRACE]]
1055
** The [SQLITE_FCNTL_TRACE] file control provides advisory information
1056
** to the VFS about what the higher layers of the SQLite stack are doing.
1057
** This file control is used by some VFS activity tracing [shims].
1058
** The argument is a zero-terminated string.  Higher layers in the
1059
** SQLite stack may generate instances of this file control if
1060
** the [SQLITE_USE_FCNTL_TRACE] compile-time option is enabled.
1061
**
1062
** <li>[[SQLITE_FCNTL_HAS_MOVED]]
1063
** The [SQLITE_FCNTL_HAS_MOVED] file control interprets its argument as a
1064
** pointer to an integer and it writes a boolean into that integer depending
1065
** on whether or not the file has been renamed, moved, or deleted since it
1066
** was first opened.
1067
**
1068
** <li>[[SQLITE_FCNTL_WIN32_GET_HANDLE]]
1069
** The [SQLITE_FCNTL_WIN32_GET_HANDLE] opcode can be used to obtain the
1070
** underlying native file handle associated with a file handle.  This file
1071
** control interprets its argument as a pointer to a native file handle and
1072
** writes the resulting value there.
1073
**
1074
** <li>[[SQLITE_FCNTL_WIN32_SET_HANDLE]]
1075
** The [SQLITE_FCNTL_WIN32_SET_HANDLE] opcode is used for debugging.  This
1076
** opcode causes the xFileControl method to swap the file handle with the one
1077
** pointed to by the pArg argument.  This capability is used during testing
1078
** and only needs to be supported when SQLITE_TEST is defined.
1079
**
1080
** <li>[[SQLITE_FCNTL_WAL_BLOCK]]
1081
** The [SQLITE_FCNTL_WAL_BLOCK] is a signal to the VFS layer that it might
1082
** be advantageous to block on the next WAL lock if the lock is not immediately
1083
** available.  The WAL subsystem issues this signal during rare
1084
** circumstances in order to fix a problem with priority inversion.
1085
** Applications should <em>not</em> use this file-control.
1086
**
1087
** <li>[[SQLITE_FCNTL_ZIPVFS]]
1088
** The [SQLITE_FCNTL_ZIPVFS] opcode is implemented by zipvfs only. All other
1089
** VFS should return SQLITE_NOTFOUND for this opcode.
1090
**
1091
** <li>[[SQLITE_FCNTL_RBU]]
1092
** The [SQLITE_FCNTL_RBU] opcode is implemented by the special VFS used by
1093
** the RBU extension only.  All other VFS should return SQLITE_NOTFOUND for
1094
** this opcode.
1095
**
1096
** <li>[[SQLITE_FCNTL_BEGIN_ATOMIC_WRITE]]
1097
** If the [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE] opcode returns SQLITE_OK, then
1098
** the file descriptor is placed in "batch write mode", which
1099
** means all subsequent write operations will be deferred and done
1100
** atomically at the next [SQLITE_FCNTL_COMMIT_ATOMIC_WRITE].  Systems
1101
** that do not support batch atomic writes will return SQLITE_NOTFOUND.
1102
** ^Following a successful SQLITE_FCNTL_BEGIN_ATOMIC_WRITE and prior to
1103
** the closing [SQLITE_FCNTL_COMMIT_ATOMIC_WRITE] or
1104
** [SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE], SQLite will make
1105
** no VFS interface calls on the same [sqlite3_file] file descriptor
1106
** except for calls to the xWrite method and the xFileControl method
1107
** with [SQLITE_FCNTL_SIZE_HINT].
1108
**
1109
** <li>[[SQLITE_FCNTL_COMMIT_ATOMIC_WRITE]]
1110
** The [SQLITE_FCNTL_COMMIT_ATOMIC_WRITE] opcode causes all write
1111
** operations since the previous successful call to
1112
** [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE] to be performed atomically.
1113
** This file control returns [SQLITE_OK] if and only if the writes were
1114
** all performed successfully and have been committed to persistent storage.
1115
** ^Regardless of whether or not it is successful, this file control takes
1116
** the file descriptor out of batch write mode so that all subsequent
1117
** write operations are independent.
1118
** ^SQLite will never invoke SQLITE_FCNTL_COMMIT_ATOMIC_WRITE without
1119
** a prior successful call to [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE].
1120
**
1121
** <li>[[SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE]]
1122
** The [SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE] opcode causes all write
1123
** operations since the previous successful call to
1124
** [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE] to be rolled back.
1125
** ^This file control takes the file descriptor out of batch write mode
1126
** so that all subsequent write operations are independent.
1127
** ^SQLite will never invoke SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE without
1128
** a prior successful call to [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE].
1129
**
1130
** <li>[[SQLITE_FCNTL_LOCK_TIMEOUT]]
1131
** The [SQLITE_FCNTL_LOCK_TIMEOUT] opcode is used to configure a VFS
1132
** to block for up to M milliseconds before failing when attempting to
1133
** obtain a file lock using the xLock or xShmLock methods of the VFS.
1134
** The parameter is a pointer to a 32-bit signed integer that contains
1135
** the value that M is to be set to. Before returning, the 32-bit signed
1136
** integer is overwritten with the previous value of M.
1137
**
1138
** <li>[[SQLITE_FCNTL_DATA_VERSION]]
1139
** The [SQLITE_FCNTL_DATA_VERSION] opcode is used to detect changes to
1140
** a database file.  The argument is a pointer to a 32-bit unsigned integer.
1141
** The "data version" for the pager is written into the pointer.  The
1142
** "data version" changes whenever any change occurs to the corresponding
1143
** database file, either through SQL statements on the same database
1144
** connection or through transactions committed by separate database
1145
** connections possibly in other processes. The [sqlite3_total_changes()]
1146
** interface can be used to find if any database on the connection has changed,
1147
** but that interface responds to changes on TEMP as well as MAIN and does
1148
** not provide a mechanism to detect changes to MAIN only.  Also, the
1149
** [sqlite3_total_changes()] interface responds to internal changes only and
1150
** omits changes made by other database connections.  The
1151
** [PRAGMA data_version] command provides a mechanism to detect changes to
1152
** a single attached database that occur due to other database connections,
1153
** but omits changes implemented by the database connection on which it is
1154
** called.  This file control is the only mechanism to detect changes that
1155
** happen either internally or externally and that are associated with
1156
** a particular attached database.
1157
**
1158
** <li>[[SQLITE_FCNTL_CKPT_START]]
1159
** The [SQLITE_FCNTL_CKPT_START] opcode is invoked from within a checkpoint
1160
** in wal mode before the client starts to copy pages from the wal
1161
** file to the database file.
1162
**
1163
** <li>[[SQLITE_FCNTL_CKPT_DONE]]
1164
** The [SQLITE_FCNTL_CKPT_DONE] opcode is invoked from within a checkpoint
1165
** in wal mode after the client has finished copying pages from the wal
1166
** file to the database file, but before the *-shm file is updated to
1167
** record the fact that the pages have been checkpointed.
1168
** </ul>
1169
**
1170
** <li>[[SQLITE_FCNTL_EXTERNAL_READER]]
1171
** The EXPERIMENTAL [SQLITE_FCNTL_EXTERNAL_READER] opcode is used to detect
1172
** whether or not there is a database client in another process with a wal-mode
1173
** transaction open on the database or not. It is only available on unix.The
1174
** (void*) argument passed with this file-control should be a pointer to a
1175
** value of type (int). The integer value is set to 1 if the database is a wal
1176
** mode database and there exists at least one client in another process that
1177
** currently has an SQL transaction open on the database. It is set to 0 if
1178
** the database is not a wal-mode db, or if there is no such connection in any
1179
** other process. This opcode cannot be used to detect transactions opened
1180
** by clients within the current process, only within other processes.
1181
** </ul>
1182
**
1183
** <li>[[SQLITE_FCNTL_CKSM_FILE]]
1184
** Used by the cksmvfs VFS module only.
1185
** </ul>
1186
*/
1187
#define SQLITE_FCNTL_LOCKSTATE               1
1188
#define SQLITE_FCNTL_GET_LOCKPROXYFILE       2
1189
#define SQLITE_FCNTL_SET_LOCKPROXYFILE       3
1190
#define SQLITE_FCNTL_LAST_ERRNO              4
1191
#define SQLITE_FCNTL_SIZE_HINT               5
1192
#define SQLITE_FCNTL_CHUNK_SIZE              6
1193
#define SQLITE_FCNTL_FILE_POINTER            7
1194
#define SQLITE_FCNTL_SYNC_OMITTED            8
1195
#define SQLITE_FCNTL_WIN32_AV_RETRY          9
1196
#define SQLITE_FCNTL_PERSIST_WAL            10
1197
#define SQLITE_FCNTL_OVERWRITE              11
1198
#define SQLITE_FCNTL_VFSNAME                12
1199
#define SQLITE_FCNTL_POWERSAFE_OVERWRITE    13
1200
#define SQLITE_FCNTL_PRAGMA                 14
1201
#define SQLITE_FCNTL_BUSYHANDLER            15
1202
#define SQLITE_FCNTL_TEMPFILENAME           16
1203
#define SQLITE_FCNTL_MMAP_SIZE              18
1204
#define SQLITE_FCNTL_TRACE                  19
1205
#define SQLITE_FCNTL_HAS_MOVED              20
1206
#define SQLITE_FCNTL_SYNC                   21
1207
#define SQLITE_FCNTL_COMMIT_PHASETWO        22
1208
#define SQLITE_FCNTL_WIN32_SET_HANDLE       23
1209
#define SQLITE_FCNTL_WAL_BLOCK              24
1210
#define SQLITE_FCNTL_ZIPVFS                 25
1211
#define SQLITE_FCNTL_RBU                    26
1212
#define SQLITE_FCNTL_VFS_POINTER            27
1213
#define SQLITE_FCNTL_JOURNAL_POINTER        28
1214
#define SQLITE_FCNTL_WIN32_GET_HANDLE       29
1215
#define SQLITE_FCNTL_PDB                    30
1216
#define SQLITE_FCNTL_BEGIN_ATOMIC_WRITE     31
1217
#define SQLITE_FCNTL_COMMIT_ATOMIC_WRITE    32
1218
#define SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE  33
1219
#define SQLITE_FCNTL_LOCK_TIMEOUT           34
1220
#define SQLITE_FCNTL_DATA_VERSION           35
1221
#define SQLITE_FCNTL_SIZE_LIMIT             36
1222
#define SQLITE_FCNTL_CKPT_DONE              37
1223
#define SQLITE_FCNTL_RESERVE_BYTES          38
1224
#define SQLITE_FCNTL_CKPT_START             39
1225
#define SQLITE_FCNTL_EXTERNAL_READER        40
1226
#define SQLITE_FCNTL_CKSM_FILE              41
1227
1228
/* deprecated names */
1229
#define SQLITE_GET_LOCKPROXYFILE      SQLITE_FCNTL_GET_LOCKPROXYFILE
1230
#define SQLITE_SET_LOCKPROXYFILE      SQLITE_FCNTL_SET_LOCKPROXYFILE
1231
#define SQLITE_LAST_ERRNO             SQLITE_FCNTL_LAST_ERRNO
1232
1233
1234
/*
1235
** CAPI3REF: Mutex Handle
1236
**
1237
** The mutex module within SQLite defines [sqlite3_mutex] to be an
1238
** abstract type for a mutex object.  The SQLite core never looks
1239
** at the internal representation of an [sqlite3_mutex].  It only
1240
** deals with pointers to the [sqlite3_mutex] object.
1241
**
1242
** Mutexes are created using [sqlite3_mutex_alloc()].
1243
*/
1244
typedef struct sqlite3_mutex sqlite3_mutex;
1245
1246
/*
1247
** CAPI3REF: Loadable Extension Thunk
1248
**
1249
** A pointer to the opaque sqlite3_api_routines structure is passed as
1250
** the third parameter to entry points of [loadable extensions].  This
1251
** structure must be typedefed in order to work around compiler warnings
1252
** on some platforms.
1253
*/
1254
typedef struct sqlite3_api_routines sqlite3_api_routines;
1255
1256
/*
1257
** CAPI3REF: OS Interface Object
1258
**
1259
** An instance of the sqlite3_vfs object defines the interface between
1260
** the SQLite core and the underlying operating system.  The "vfs"
1261
** in the name of the object stands for "virtual file system".  See
1262
** the [VFS | VFS documentation] for further information.
1263
**
1264
** The VFS interface is sometimes extended by adding new methods onto
1265
** the end.  Each time such an extension occurs, the iVersion field
1266
** is incremented.  The iVersion value started out as 1 in
1267
** SQLite [version 3.5.0] on [dateof:3.5.0], then increased to 2
1268
** with SQLite [version 3.7.0] on [dateof:3.7.0], and then increased
1269
** to 3 with SQLite [version 3.7.6] on [dateof:3.7.6].  Additional fields
1270
** may be appended to the sqlite3_vfs object and the iVersion value
1271
** may increase again in future versions of SQLite.
1272
** Note that due to an oversight, the structure
1273
** of the sqlite3_vfs object changed in the transition from
1274
** SQLite [version 3.5.9] to [version 3.6.0] on [dateof:3.6.0]
1275
** and yet the iVersion field was not increased.
1276
**
1277
** The szOsFile field is the size of the subclassed [sqlite3_file]
1278
** structure used by this VFS.  mxPathname is the maximum length of
1279
** a pathname in this VFS.
1280
**
1281
** Registered sqlite3_vfs objects are kept on a linked list formed by
1282
** the pNext pointer.  The [sqlite3_vfs_register()]
1283
** and [sqlite3_vfs_unregister()] interfaces manage this list
1284
** in a thread-safe way.  The [sqlite3_vfs_find()] interface
1285
** searches the list.  Neither the application code nor the VFS
1286
** implementation should use the pNext pointer.
1287
**
1288
** The pNext field is the only field in the sqlite3_vfs
1289
** structure that SQLite will ever modify.  SQLite will only access
1290
** or modify this field while holding a particular static mutex.
1291
** The application should never modify anything within the sqlite3_vfs
1292
** object once the object has been registered.
1293
**
1294
** The zName field holds the name of the VFS module.  The name must
1295
** be unique across all VFS modules.
1296
**
1297
** [[sqlite3_vfs.xOpen]]
1298
** ^SQLite guarantees that the zFilename parameter to xOpen
1299
** is either a NULL pointer or string obtained
1300
** from xFullPathname() with an optional suffix added.
1301
** ^If a suffix is added to the zFilename parameter, it will
1302
** consist of a single "-" character followed by no more than
1303
** 11 alphanumeric and/or "-" characters.
1304
** ^SQLite further guarantees that
1305
** the string will be valid and unchanged until xClose() is
1306
** called. Because of the previous sentence,
1307
** the [sqlite3_file] can safely store a pointer to the
1308
** filename if it needs to remember the filename for some reason.
1309
** If the zFilename parameter to xOpen is a NULL pointer then xOpen
1310
** must invent its own temporary name for the file.  ^Whenever the
1311
** xFilename parameter is NULL it will also be the case that the
1312
** flags parameter will include [SQLITE_OPEN_DELETEONCLOSE].
1313
**
1314
** The flags argument to xOpen() includes all bits set in
1315
** the flags argument to [sqlite3_open_v2()].  Or if [sqlite3_open()]
1316
** or [sqlite3_open16()] is used, then flags includes at least
1317
** [SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE].
1318
** If xOpen() opens a file read-only then it sets *pOutFlags to
1319
** include [SQLITE_OPEN_READONLY].  Other bits in *pOutFlags may be set.
1320
**
1321
** ^(SQLite will also add one of the following flags to the xOpen()
1322
** call, depending on the object being opened:
1323
**
1324
** <ul>
1325
** <li>  [SQLITE_OPEN_MAIN_DB]
1326
** <li>  [SQLITE_OPEN_MAIN_JOURNAL]
1327
** <li>  [SQLITE_OPEN_TEMP_DB]
1328
** <li>  [SQLITE_OPEN_TEMP_JOURNAL]
1329
** <li>  [SQLITE_OPEN_TRANSIENT_DB]
1330
** <li>  [SQLITE_OPEN_SUBJOURNAL]
1331
** <li>  [SQLITE_OPEN_SUPER_JOURNAL]
1332
** <li>  [SQLITE_OPEN_WAL]
1333
** </ul>)^
1334
**
1335
** The file I/O implementation can use the object type flags to
1336
** change the way it deals with files.  For example, an application
1337
** that does not care about crash recovery or rollback might make
1338
** the open of a journal file a no-op.  Writes to this journal would
1339
** also be no-ops, and any attempt to read the journal would return
1340
** SQLITE_IOERR.  Or the implementation might recognize that a database
1341
** file will be doing page-aligned sector reads and writes in a random
1342
** order and set up its I/O subsystem accordingly.
1343
**
1344
** SQLite might also add one of the following flags to the xOpen method:
1345
**
1346
** <ul>
1347
** <li> [SQLITE_OPEN_DELETEONCLOSE]
1348
** <li> [SQLITE_OPEN_EXCLUSIVE]
1349
** </ul>
1350
**
1351
** The [SQLITE_OPEN_DELETEONCLOSE] flag means the file should be
1352
** deleted when it is closed.  ^The [SQLITE_OPEN_DELETEONCLOSE]
1353
** will be set for TEMP databases and their journals, transient
1354
** databases, and subjournals.
1355
**
1356
** ^The [SQLITE_OPEN_EXCLUSIVE] flag is always used in conjunction
1357
** with the [SQLITE_OPEN_CREATE] flag, which are both directly
1358
** analogous to the O_EXCL and O_CREAT flags of the POSIX open()
1359
** API.  The SQLITE_OPEN_EXCLUSIVE flag, when paired with the
1360
** SQLITE_OPEN_CREATE, is used to indicate that file should always
1361
** be created, and that it is an error if it already exists.
1362
** It is <i>not</i> used to indicate the file should be opened
1363
** for exclusive access.
1364
**
1365
** ^At least szOsFile bytes of memory are allocated by SQLite
1366
** to hold the [sqlite3_file] structure passed as the third
1367
** argument to xOpen.  The xOpen method does not have to
1368
** allocate the structure; it should just fill it in.  Note that
1369
** the xOpen method must set the sqlite3_file.pMethods to either
1370
** a valid [sqlite3_io_methods] object or to NULL.  xOpen must do
1371
** this even if the open fails.  SQLite expects that the sqlite3_file.pMethods
1372
** element will be valid after xOpen returns regardless of the success
1373
** or failure of the xOpen call.
1374
**
1375
** [[sqlite3_vfs.xAccess]]
1376
** ^The flags argument to xAccess() may be [SQLITE_ACCESS_EXISTS]
1377
** to test for the existence of a file, or [SQLITE_ACCESS_READWRITE] to
1378
** test whether a file is readable and writable, or [SQLITE_ACCESS_READ]
1379
** to test whether a file is at least readable.  The SQLITE_ACCESS_READ
1380
** flag is never actually used and is not implemented in the built-in
1381
** VFSes of SQLite.  The file is named by the second argument and can be a
1382
** directory. The xAccess method returns [SQLITE_OK] on success or some
1383
** non-zero error code if there is an I/O error or if the name of
1384
** the file given in the second argument is illegal.  If SQLITE_OK
1385
** is returned, then non-zero or zero is written into *pResOut to indicate
1386
** whether or not the file is accessible.
1387
**
1388
** ^SQLite will always allocate at least mxPathname+1 bytes for the
1389
** output buffer xFullPathname.  The exact size of the output buffer
1390
** is also passed as a parameter to both  methods. If the output buffer
1391
** is not large enough, [SQLITE_CANTOPEN] should be returned. Since this is
1392
** handled as a fatal error by SQLite, vfs implementations should endeavor
1393
** to prevent this by setting mxPathname to a sufficiently large value.
1394
**
1395
** The xRandomness(), xSleep(), xCurrentTime(), and xCurrentTimeInt64()
1396
** interfaces are not strictly a part of the filesystem, but they are
1397
** included in the VFS structure for completeness.
1398
** The xRandomness() function attempts to return nBytes bytes
1399
** of good-quality randomness into zOut.  The return value is
1400
** the actual number of bytes of randomness obtained.
1401
** The xSleep() method causes the calling thread to sleep for at
1402
** least the number of microseconds given.  ^The xCurrentTime()
1403
** method returns a Julian Day Number for the current date and time as
1404
** a floating point value.
1405
** ^The xCurrentTimeInt64() method returns, as an integer, the Julian
1406
** Day Number multiplied by 86400000 (the number of milliseconds in
1407
** a 24-hour day).
1408
** ^SQLite will use the xCurrentTimeInt64() method to get the current
1409
** date and time if that method is available (if iVersion is 2 or
1410
** greater and the function pointer is not NULL) and will fall back
1411
** to xCurrentTime() if xCurrentTimeInt64() is unavailable.
1412
**
1413
** ^The xSetSystemCall(), xGetSystemCall(), and xNestSystemCall() interfaces
1414
** are not used by the SQLite core.  These optional interfaces are provided
1415
** by some VFSes to facilitate testing of the VFS code. By overriding
1416
** system calls with functions under its control, a test program can
1417
** simulate faults and error conditions that would otherwise be difficult
1418
** or impossible to induce.  The set of system calls that can be overridden
1419
** varies from one VFS to another, and from one version of the same VFS to the
1420
** next.  Applications that use these interfaces must be prepared for any
1421
** or all of these interfaces to be NULL or for their behavior to change
1422
** from one release to the next.  Applications must not attempt to access
1423
** any of these methods if the iVersion of the VFS is less than 3.
1424
*/
1425
typedef struct sqlite3_vfs sqlite3_vfs;
1426
typedef void (*sqlite3_syscall_ptr)(void);
1427
struct sqlite3_vfs {
1428
  int iVersion;            /* Structure version number (currently 3) */
1429
  int szOsFile;            /* Size of subclassed sqlite3_file */
1430
  int mxPathname;          /* Maximum file pathname length */
1431
  sqlite3_vfs *pNext;      /* Next registered VFS */
1432
  const char *zName;       /* Name of this virtual file system */
1433
  void *pAppData;          /* Pointer to application-specific data */
1434
  int (*xOpen)(sqlite3_vfs*, const char *zName, sqlite3_file*,
1435
               int flags, int *pOutFlags);
1436
  int (*xDelete)(sqlite3_vfs*, const char *zName, int syncDir);
1437
  int (*xAccess)(sqlite3_vfs*, const char *zName, int flags, int *pResOut);
1438
  int (*xFullPathname)(sqlite3_vfs*, const char *zName, int nOut, char *zOut);
1439
  void *(*xDlOpen)(sqlite3_vfs*, const char *zFilename);
1440
  void (*xDlError)(sqlite3_vfs*, int nByte, char *zErrMsg);
1441
  void (*(*xDlSym)(sqlite3_vfs*,void*, const char *zSymbol))(void);
1442
  void (*xDlClose)(sqlite3_vfs*, void*);
1443
  int (*xRandomness)(sqlite3_vfs*, int nByte, char *zOut);
1444
  int (*xSleep)(sqlite3_vfs*, int microseconds);
1445
  int (*xCurrentTime)(sqlite3_vfs*, double*);
1446
  int (*xGetLastError)(sqlite3_vfs*, int, char *);
1447
  /*
1448
  ** The methods above are in version 1 of the sqlite_vfs object
1449
  ** definition.  Those that follow are added in version 2 or later
1450
  */
1451
  int (*xCurrentTimeInt64)(sqlite3_vfs*, sqlite3_int64*);
1452
  /*
1453
  ** The methods above are in versions 1 and 2 of the sqlite_vfs object.
1454
  ** Those below are for version 3 and greater.
1455
  */
1456
  int (*xSetSystemCall)(sqlite3_vfs*, const char *zName, sqlite3_syscall_ptr);
1457
  sqlite3_syscall_ptr (*xGetSystemCall)(sqlite3_vfs*, const char *zName);
1458
  const char *(*xNextSystemCall)(sqlite3_vfs*, const char *zName);
1459
  /*
1460
  ** The methods above are in versions 1 through 3 of the sqlite_vfs object.
1461
  ** New fields may be appended in future versions.  The iVersion
1462
  ** value will increment whenever this happens.
1463
  */
1464
};
1465
1466
/*
1467
** CAPI3REF: Flags for the xAccess VFS method
1468
**
1469
** These integer constants can be used as the third parameter to
1470
** the xAccess method of an [sqlite3_vfs] object.  They determine
1471
** what kind of permissions the xAccess method is looking for.
1472
** With SQLITE_ACCESS_EXISTS, the xAccess method
1473
** simply checks whether the file exists.
1474
** With SQLITE_ACCESS_READWRITE, the xAccess method
1475
** checks whether the named directory is both readable and writable
1476
** (in other words, if files can be added, removed, and renamed within
1477
** the directory).
1478
** The SQLITE_ACCESS_READWRITE constant is currently used only by the
1479
** [temp_store_directory pragma], though this could change in a future
1480
** release of SQLite.
1481
** With SQLITE_ACCESS_READ, the xAccess method
1482
** checks whether the file is readable.  The SQLITE_ACCESS_READ constant is
1483
** currently unused, though it might be used in a future release of
1484
** SQLite.
1485
*/
1486
#define SQLITE_ACCESS_EXISTS    0
1487
#define SQLITE_ACCESS_READWRITE 1   /* Used by PRAGMA temp_store_directory */
1488
#define SQLITE_ACCESS_READ      2   /* Unused */
1489
1490
/*
1491
** CAPI3REF: Flags for the xShmLock VFS method
1492
**
1493
** These integer constants define the various locking operations
1494
** allowed by the xShmLock method of [sqlite3_io_methods].  The
1495
** following are the only legal combinations of flags to the
1496
** xShmLock method:
1497
**
1498
** <ul>
1499
** <li>  SQLITE_SHM_LOCK | SQLITE_SHM_SHARED
1500
** <li>  SQLITE_SHM_LOCK | SQLITE_SHM_EXCLUSIVE
1501
** <li>  SQLITE_SHM_UNLOCK | SQLITE_SHM_SHARED
1502
** <li>  SQLITE_SHM_UNLOCK | SQLITE_SHM_EXCLUSIVE
1503
** </ul>
1504
**
1505
** When unlocking, the same SHARED or EXCLUSIVE flag must be supplied as
1506
** was given on the corresponding lock.
1507
**
1508
** The xShmLock method can transition between unlocked and SHARED or
1509
** between unlocked and EXCLUSIVE.  It cannot transition between SHARED
1510
** and EXCLUSIVE.
1511
*/
1512
#define SQLITE_SHM_UNLOCK       1
1513
#define SQLITE_SHM_LOCK         2
1514
#define SQLITE_SHM_SHARED       4
1515
#define SQLITE_SHM_EXCLUSIVE    8
1516
1517
/*
1518
** CAPI3REF: Maximum xShmLock index
1519
**
1520
** The xShmLock method on [sqlite3_io_methods] may use values
1521
** between 0 and this upper bound as its "offset" argument.
1522
** The SQLite core will never attempt to acquire or release a
1523
** lock outside of this range
1524
*/
1525
#define SQLITE_SHM_NLOCK        8
1526
1527
1528
/*
1529
** CAPI3REF: Initialize The SQLite Library
1530
**
1531
** ^The sqlite3_initialize() routine initializes the
1532
** SQLite library.  ^The sqlite3_shutdown() routine
1533
** deallocates any resources that were allocated by sqlite3_initialize().
1534
** These routines are designed to aid in process initialization and
1535
** shutdown on embedded systems.  Workstation applications using
1536
** SQLite normally do not need to invoke either of these routines.
1537
**
1538
** A call to sqlite3_initialize() is an "effective" call if it is
1539
** the first time sqlite3_initialize() is invoked during the lifetime of
1540
** the process, or if it is the first time sqlite3_initialize() is invoked
1541
** following a call to sqlite3_shutdown().  ^(Only an effective call
1542
** of sqlite3_initialize() does any initialization.  All other calls
1543
** are harmless no-ops.)^
1544
**
1545
** A call to sqlite3_shutdown() is an "effective" call if it is the first
1546
** call to sqlite3_shutdown() since the last sqlite3_initialize().  ^(Only
1547
** an effective call to sqlite3_shutdown() does any deinitialization.
1548
** All other valid calls to sqlite3_shutdown() are harmless no-ops.)^
1549
**
1550
** The sqlite3_initialize() interface is threadsafe, but sqlite3_shutdown()
1551
** is not.  The sqlite3_shutdown() interface must only be called from a
1552
** single thread.  All open [database connections] must be closed and all
1553
** other SQLite resources must be deallocated prior to invoking
1554
** sqlite3_shutdown().
1555
**
1556
** Among other things, ^sqlite3_initialize() will invoke
1557
** sqlite3_os_init().  Similarly, ^sqlite3_shutdown()
1558
** will invoke sqlite3_os_end().
1559
**
1560
** ^The sqlite3_initialize() routine returns [SQLITE_OK] on success.
1561
** ^If for some reason, sqlite3_initialize() is unable to initialize
1562
** the library (perhaps it is unable to allocate a needed resource such
1563
** as a mutex) it returns an [error code] other than [SQLITE_OK].
1564
**
1565
** ^The sqlite3_initialize() routine is called internally by many other
1566
** SQLite interfaces so that an application usually does not need to
1567
** invoke sqlite3_initialize() directly.  For example, [sqlite3_open()]
1568
** calls sqlite3_initialize() so the SQLite library will be automatically
1569
** initialized when [sqlite3_open()] is called if it has not be initialized
1570
** already.  ^However, if SQLite is compiled with the [SQLITE_OMIT_AUTOINIT]
1571
** compile-time option, then the automatic calls to sqlite3_initialize()
1572
** are omitted and the application must call sqlite3_initialize() directly
1573
** prior to using any other SQLite interface.  For maximum portability,
1574
** it is recommended that applications always invoke sqlite3_initialize()
1575
** directly prior to using any other SQLite interface.  Future releases
1576
** of SQLite may require this.  In other words, the behavior exhibited
1577
** when SQLite is compiled with [SQLITE_OMIT_AUTOINIT] might become the
1578
** default behavior in some future release of SQLite.
1579
**
1580
** The sqlite3_os_init() routine does operating-system specific
1581
** initialization of the SQLite library.  The sqlite3_os_end()
1582
** routine undoes the effect of sqlite3_os_init().  Typical tasks
1583
** performed by these routines include allocation or deallocation
1584
** of static resources, initialization of global variables,
1585
** setting up a default [sqlite3_vfs] module, or setting up
1586
** a default configuration using [sqlite3_config()].
1587
**
1588
** The application should never invoke either sqlite3_os_init()
1589
** or sqlite3_os_end() directly.  The application should only invoke
1590
** sqlite3_initialize() and sqlite3_shutdown().  The sqlite3_os_init()
1591
** interface is called automatically by sqlite3_initialize() and
1592
** sqlite3_os_end() is called by sqlite3_shutdown().  Appropriate
1593
** implementations for sqlite3_os_init() and sqlite3_os_end()
1594
** are built into SQLite when it is compiled for Unix, Windows, or OS/2.
1595
** When [custom builds | built for other platforms]
1596
** (using the [SQLITE_OS_OTHER=1] compile-time
1597
** option) the application must supply a suitable implementation for
1598
** sqlite3_os_init() and sqlite3_os_end().  An application-supplied
1599
** implementation of sqlite3_os_init() or sqlite3_os_end()
1600
** must return [SQLITE_OK] on success and some other [error code] upon
1601
** failure.
1602
*/
1603
SQLITE_API int sqlite3_initialize(void);
1604
SQLITE_API int sqlite3_shutdown(void);
1605
SQLITE_API int sqlite3_os_init(void);
1606
SQLITE_API int sqlite3_os_end(void);
1607
1608
/*
1609
** CAPI3REF: Configuring The SQLite Library
1610
**
1611
** The sqlite3_config() interface is used to make global configuration
1612
** changes to SQLite in order to tune SQLite to the specific needs of
1613
** the application.  The default configuration is recommended for most
1614
** applications and so this routine is usually not necessary.  It is
1615
** provided to support rare applications with unusual needs.
1616
**
1617
** <b>The sqlite3_config() interface is not threadsafe. The application
1618
** must ensure that no other SQLite interfaces are invoked by other
1619
** threads while sqlite3_config() is running.</b>
1620
**
1621
** The sqlite3_config() interface
1622
** may only be invoked prior to library initialization using
1623
** [sqlite3_initialize()] or after shutdown by [sqlite3_shutdown()].
1624
** ^If sqlite3_config() is called after [sqlite3_initialize()] and before
1625
** [sqlite3_shutdown()] then it will return SQLITE_MISUSE.
1626
** Note, however, that ^sqlite3_config() can be called as part of the
1627
** implementation of an application-defined [sqlite3_os_init()].
1628
**
1629
** The first argument to sqlite3_config() is an integer
1630
** [configuration option] that determines
1631
** what property of SQLite is to be configured.  Subsequent arguments
1632
** vary depending on the [configuration option]
1633
** in the first argument.
1634
**
1635
** ^When a configuration option is set, sqlite3_config() returns [SQLITE_OK].
1636
** ^If the option is unknown or SQLite is unable to set the option
1637
** then this routine returns a non-zero [error code].
1638
*/
1639
SQLITE_API int sqlite3_config(int, ...);
1640
1641
/*
1642
** CAPI3REF: Configure database connections
1643
** METHOD: sqlite3
1644
**
1645
** The sqlite3_db_config() interface is used to make configuration
1646
** changes to a [database connection].  The interface is similar to
1647
** [sqlite3_config()] except that the changes apply to a single
1648
** [database connection] (specified in the first argument).
1649
**
1650
** The second argument to sqlite3_db_config(D,V,...)  is the
1651
** [SQLITE_DBCONFIG_LOOKASIDE | configuration verb] - an integer code
1652
** that indicates what aspect of the [database connection] is being configured.
1653
** Subsequent arguments vary depending on the configuration verb.
1654
**
1655
** ^Calls to sqlite3_db_config() return SQLITE_OK if and only if
1656
** the call is considered successful.
1657
*/
1658
SQLITE_API int sqlite3_db_config(sqlite3*, int op, ...);
1659
1660
/*
1661
** CAPI3REF: Memory Allocation Routines
1662
**
1663
** An instance of this object defines the interface between SQLite
1664
** and low-level memory allocation routines.
1665
**
1666
** This object is used in only one place in the SQLite interface.
1667
** A pointer to an instance of this object is the argument to
1668
** [sqlite3_config()] when the configuration option is
1669
** [SQLITE_CONFIG_MALLOC] or [SQLITE_CONFIG_GETMALLOC].
1670
** By creating an instance of this object
1671
** and passing it to [sqlite3_config]([SQLITE_CONFIG_MALLOC])
1672
** during configuration, an application can specify an alternative
1673
** memory allocation subsystem for SQLite to use for all of its
1674
** dynamic memory needs.
1675
**
1676
** Note that SQLite comes with several [built-in memory allocators]
1677
** that are perfectly adequate for the overwhelming majority of applications
1678
** and that this object is only useful to a tiny minority of applications
1679
** with specialized memory allocation requirements.  This object is
1680
** also used during testing of SQLite in order to specify an alternative
1681
** memory allocator that simulates memory out-of-memory conditions in
1682
** order to verify that SQLite recovers gracefully from such
1683
** conditions.
1684
**
1685
** The xMalloc, xRealloc, and xFree methods must work like the
1686
** malloc(), realloc() and free() functions from the standard C library.
1687
** ^SQLite guarantees that the second argument to
1688
** xRealloc is always a value returned by a prior call to xRoundup.
1689
**
1690
** xSize should return the allocated size of a memory allocation
1691
** previously obtained from xMalloc or xRealloc.  The allocated size
1692
** is always at least as big as the requested size but may be larger.
1693
**
1694
** The xRoundup method returns what would be the allocated size of
1695
** a memory allocation given a particular requested size.  Most memory
1696
** allocators round up memory allocations at least to the next multiple
1697
** of 8.  Some allocators round up to a larger multiple or to a power of 2.
1698
** Every memory allocation request coming in through [sqlite3_malloc()]
1699
** or [sqlite3_realloc()] first calls xRoundup.  If xRoundup returns 0,
1700
** that causes the corresponding memory allocation to fail.
1701
**
1702
** The xInit method initializes the memory allocator.  For example,
1703
** it might allocate any required mutexes or initialize internal data
1704
** structures.  The xShutdown method is invoked (indirectly) by
1705
** [sqlite3_shutdown()] and should deallocate any resources acquired
1706
** by xInit.  The pAppData pointer is used as the only parameter to
1707
** xInit and xShutdown.
1708
**
1709
** SQLite holds the [SQLITE_MUTEX_STATIC_MAIN] mutex when it invokes
1710
** the xInit method, so the xInit method need not be threadsafe.  The
1711
** xShutdown method is only called from [sqlite3_shutdown()] so it does
1712
** not need to be threadsafe either.  For all other methods, SQLite
1713
** holds the [SQLITE_MUTEX_STATIC_MEM] mutex as long as the
1714
** [SQLITE_CONFIG_MEMSTATUS] configuration option is turned on (which
1715
** it is by default) and so the methods are automatically serialized.
1716
** However, if [SQLITE_CONFIG_MEMSTATUS] is disabled, then the other
1717
** methods must be threadsafe or else make their own arrangements for
1718
** serialization.
1719
**
1720
** SQLite will never invoke xInit() more than once without an intervening
1721
** call to xShutdown().
1722
*/
1723
typedef struct sqlite3_mem_methods sqlite3_mem_methods;
1724
struct sqlite3_mem_methods {
1725
  void *(*xMalloc)(int);         /* Memory allocation function */
1726
  void (*xFree)(void*);          /* Free a prior allocation */
1727
  void *(*xRealloc)(void*,int);  /* Resize an allocation */
1728
  int (*xSize)(void*);           /* Return the size of an allocation */
1729
  int (*xRoundup)(int);          /* Round up request size to allocation size */
1730
  int (*xInit)(void*);           /* Initialize the memory allocator */
1731
  void (*xShutdown)(void*);      /* Deinitialize the memory allocator */
1732
  void *pAppData;                /* Argument to xInit() and xShutdown() */
1733
};
1734
1735
/*
1736
** CAPI3REF: Configuration Options
1737
** KEYWORDS: {configuration option}
1738
**
1739
** These constants are the available integer configuration options that
1740
** can be passed as the first argument to the [sqlite3_config()] interface.
1741
**
1742
** New configuration options may be added in future releases of SQLite.
1743
** Existing configuration options might be discontinued.  Applications
1744
** should check the return code from [sqlite3_config()] to make sure that
1745
** the call worked.  The [sqlite3_config()] interface will return a
1746
** non-zero [error code] if a discontinued or unsupported configuration option
1747
** is invoked.
1748
**
1749
** <dl>
1750
** [[SQLITE_CONFIG_SINGLETHREAD]] <dt>SQLITE_CONFIG_SINGLETHREAD</dt>
1751
** <dd>There are no arguments to this option.  ^This option sets the
1752
** [threading mode] to Single-thread.  In other words, it disables
1753
** all mutexing and puts SQLite into a mode where it can only be used
1754
** by a single thread.   ^If SQLite is compiled with
1755
** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
1756
** it is not possible to change the [threading mode] from its default
1757
** value of Single-thread and so [sqlite3_config()] will return
1758
** [SQLITE_ERROR] if called with the SQLITE_CONFIG_SINGLETHREAD
1759
** configuration option.</dd>
1760
**
1761
** [[SQLITE_CONFIG_MULTITHREAD]] <dt>SQLITE_CONFIG_MULTITHREAD</dt>
1762
** <dd>There are no arguments to this option.  ^This option sets the
1763
** [threading mode] to Multi-thread.  In other words, it disables
1764
** mutexing on [database connection] and [prepared statement] objects.
1765
** The application is responsible for serializing access to
1766
** [database connections] and [prepared statements].  But other mutexes
1767
** are enabled so that SQLite will be safe to use in a multi-threaded
1768
** environment as long as no two threads attempt to use the same
1769
** [database connection] at the same time.  ^If SQLite is compiled with
1770
** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
1771
** it is not possible to set the Multi-thread [threading mode] and
1772
** [sqlite3_config()] will return [SQLITE_ERROR] if called with the
1773
** SQLITE_CONFIG_MULTITHREAD configuration option.</dd>
1774
**
1775
** [[SQLITE_CONFIG_SERIALIZED]] <dt>SQLITE_CONFIG_SERIALIZED</dt>
1776
** <dd>There are no arguments to this option.  ^This option sets the
1777
** [threading mode] to Serialized. In other words, this option enables
1778
** all mutexes including the recursive
1779
** mutexes on [database connection] and [prepared statement] objects.
1780
** In this mode (which is the default when SQLite is compiled with
1781
** [SQLITE_THREADSAFE=1]) the SQLite library will itself serialize access
1782
** to [database connections] and [prepared statements] so that the
1783
** application is free to use the same [database connection] or the
1784
** same [prepared statement] in different threads at the same time.
1785
** ^If SQLite is compiled with
1786
** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
1787
** it is not possible to set the Serialized [threading mode] and
1788
** [sqlite3_config()] will return [SQLITE_ERROR] if called with the
1789
** SQLITE_CONFIG_SERIALIZED configuration option.</dd>
1790
**
1791
** [[SQLITE_CONFIG_MALLOC]] <dt>SQLITE_CONFIG_MALLOC</dt>
1792
** <dd> ^(The SQLITE_CONFIG_MALLOC option takes a single argument which is
1793
** a pointer to an instance of the [sqlite3_mem_methods] structure.
1794
** The argument specifies
1795
** alternative low-level memory allocation routines to be used in place of
1796
** the memory allocation routines built into SQLite.)^ ^SQLite makes
1797
** its own private copy of the content of the [sqlite3_mem_methods] structure
1798
** before the [sqlite3_config()] call returns.</dd>
1799
**
1800
** [[SQLITE_CONFIG_GETMALLOC]] <dt>SQLITE_CONFIG_GETMALLOC</dt>
1801
** <dd> ^(The SQLITE_CONFIG_GETMALLOC option takes a single argument which
1802
** is a pointer to an instance of the [sqlite3_mem_methods] structure.
1803
** The [sqlite3_mem_methods]
1804
** structure is filled with the currently defined memory allocation routines.)^
1805
** This option can be used to overload the default memory allocation
1806
** routines with a wrapper that simulations memory allocation failure or
1807
** tracks memory usage, for example. </dd>
1808
**
1809
** [[SQLITE_CONFIG_SMALL_MALLOC]] <dt>SQLITE_CONFIG_SMALL_MALLOC</dt>
1810
** <dd> ^The SQLITE_CONFIG_SMALL_MALLOC option takes single argument of
1811
** type int, interpreted as a boolean, which if true provides a hint to
1812
** SQLite that it should avoid large memory allocations if possible.
1813
** SQLite will run faster if it is free to make large memory allocations,
1814
** but some application might prefer to run slower in exchange for
1815
** guarantees about memory fragmentation that are possible if large
1816
** allocations are avoided.  This hint is normally off.
1817
** </dd>
1818
**
1819
** [[SQLITE_CONFIG_MEMSTATUS]] <dt>SQLITE_CONFIG_MEMSTATUS</dt>
1820
** <dd> ^The SQLITE_CONFIG_MEMSTATUS option takes single argument of type int,
1821
** interpreted as a boolean, which enables or disables the collection of
1822
** memory allocation statistics. ^(When memory allocation statistics are
1823
** disabled, the following SQLite interfaces become non-operational:
1824
**   <ul>
1825
**   <li> [sqlite3_hard_heap_limit64()]
1826
**   <li> [sqlite3_memory_used()]
1827
**   <li> [sqlite3_memory_highwater()]
1828
**   <li> [sqlite3_soft_heap_limit64()]
1829
**   <li> [sqlite3_status64()]
1830
**   </ul>)^
1831
** ^Memory allocation statistics are enabled by default unless SQLite is
1832
** compiled with [SQLITE_DEFAULT_MEMSTATUS]=0 in which case memory
1833
** allocation statistics are disabled by default.
1834
** </dd>
1835
**
1836
** [[SQLITE_CONFIG_SCRATCH]] <dt>SQLITE_CONFIG_SCRATCH</dt>
1837
** <dd> The SQLITE_CONFIG_SCRATCH option is no longer used.
1838
** </dd>
1839
**
1840
** [[SQLITE_CONFIG_PAGECACHE]] <dt>SQLITE_CONFIG_PAGECACHE</dt>
1841
** <dd> ^The SQLITE_CONFIG_PAGECACHE option specifies a memory pool
1842
** that SQLite can use for the database page cache with the default page
1843
** cache implementation.
1844
** This configuration option is a no-op if an application-defined page
1845
** cache implementation is loaded using the [SQLITE_CONFIG_PCACHE2].
1846
** ^There are three arguments to SQLITE_CONFIG_PAGECACHE: A pointer to
1847
** 8-byte aligned memory (pMem), the size of each page cache line (sz),
1848
** and the number of cache lines (N).
1849
** The sz argument should be the size of the largest database page
1850
** (a power of two between 512 and 65536) plus some extra bytes for each
1851
** page header.  ^The number of extra bytes needed by the page header
1852
** can be determined using [SQLITE_CONFIG_PCACHE_HDRSZ].
1853
** ^It is harmless, apart from the wasted memory,
1854
** for the sz parameter to be larger than necessary.  The pMem
1855
** argument must be either a NULL pointer or a pointer to an 8-byte
1856
** aligned block of memory of at least sz*N bytes, otherwise
1857
** subsequent behavior is undefined.
1858
** ^When pMem is not NULL, SQLite will strive to use the memory provided
1859
** to satisfy page cache needs, falling back to [sqlite3_malloc()] if
1860
** a page cache line is larger than sz bytes or if all of the pMem buffer
1861
** is exhausted.
1862
** ^If pMem is NULL and N is non-zero, then each database connection
1863
** does an initial bulk allocation for page cache memory
1864
** from [sqlite3_malloc()] sufficient for N cache lines if N is positive or
1865
** of -1024*N bytes if N is negative, . ^If additional
1866
** page cache memory is needed beyond what is provided by the initial
1867
** allocation, then SQLite goes to [sqlite3_malloc()] separately for each
1868
** additional cache line. </dd>
1869
**
1870
** [[SQLITE_CONFIG_HEAP]] <dt>SQLITE_CONFIG_HEAP</dt>
1871
** <dd> ^The SQLITE_CONFIG_HEAP option specifies a static memory buffer
1872
** that SQLite will use for all of its dynamic memory allocation needs
1873
** beyond those provided for by [SQLITE_CONFIG_PAGECACHE].
1874
** ^The SQLITE_CONFIG_HEAP option is only available if SQLite is compiled
1875
** with either [SQLITE_ENABLE_MEMSYS3] or [SQLITE_ENABLE_MEMSYS5] and returns
1876
** [SQLITE_ERROR] if invoked otherwise.
1877
** ^There are three arguments to SQLITE_CONFIG_HEAP:
1878
** An 8-byte aligned pointer to the memory,
1879
** the number of bytes in the memory buffer, and the minimum allocation size.
1880
** ^If the first pointer (the memory pointer) is NULL, then SQLite reverts
1881
** to using its default memory allocator (the system malloc() implementation),
1882
** undoing any prior invocation of [SQLITE_CONFIG_MALLOC].  ^If the
1883
** memory pointer is not NULL then the alternative memory
1884
** allocator is engaged to handle all of SQLites memory allocation needs.
1885
** The first pointer (the memory pointer) must be aligned to an 8-byte
1886
** boundary or subsequent behavior of SQLite will be undefined.
1887
** The minimum allocation size is capped at 2**12. Reasonable values
1888
** for the minimum allocation size are 2**5 through 2**8.</dd>
1889
**
1890
** [[SQLITE_CONFIG_MUTEX]] <dt>SQLITE_CONFIG_MUTEX</dt>
1891
** <dd> ^(The SQLITE_CONFIG_MUTEX option takes a single argument which is a
1892
** pointer to an instance of the [sqlite3_mutex_methods] structure.
1893
** The argument specifies alternative low-level mutex routines to be used
1894
** in place the mutex routines built into SQLite.)^  ^SQLite makes a copy of
1895
** the content of the [sqlite3_mutex_methods] structure before the call to
1896
** [sqlite3_config()] returns. ^If SQLite is compiled with
1897
** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
1898
** the entire mutexing subsystem is omitted from the build and hence calls to
1899
** [sqlite3_config()] with the SQLITE_CONFIG_MUTEX configuration option will
1900
** return [SQLITE_ERROR].</dd>
1901
**
1902
** [[SQLITE_CONFIG_GETMUTEX]] <dt>SQLITE_CONFIG_GETMUTEX</dt>
1903
** <dd> ^(The SQLITE_CONFIG_GETMUTEX option takes a single argument which
1904
** is a pointer to an instance of the [sqlite3_mutex_methods] structure.  The
1905
** [sqlite3_mutex_methods]
1906
** structure is filled with the currently defined mutex routines.)^
1907
** This option can be used to overload the default mutex allocation
1908
** routines with a wrapper used to track mutex usage for performance
1909
** profiling or testing, for example.   ^If SQLite is compiled with
1910
** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
1911
** the entire mutexing subsystem is omitted from the build and hence calls to
1912
** [sqlite3_config()] with the SQLITE_CONFIG_GETMUTEX configuration option will
1913
** return [SQLITE_ERROR].</dd>
1914
**
1915
** [[SQLITE_CONFIG_LOOKASIDE]] <dt>SQLITE_CONFIG_LOOKASIDE</dt>
1916
** <dd> ^(The SQLITE_CONFIG_LOOKASIDE option takes two arguments that determine
1917
** the default size of lookaside memory on each [database connection].
1918
** The first argument is the
1919
** size of each lookaside buffer slot and the second is the number of
1920
** slots allocated to each database connection.)^  ^(SQLITE_CONFIG_LOOKASIDE
1921
** sets the <i>default</i> lookaside size. The [SQLITE_DBCONFIG_LOOKASIDE]
1922
** option to [sqlite3_db_config()] can be used to change the lookaside
1923
** configuration on individual connections.)^ </dd>
1924
**
1925
** [[SQLITE_CONFIG_PCACHE2]] <dt>SQLITE_CONFIG_PCACHE2</dt>
1926
** <dd> ^(The SQLITE_CONFIG_PCACHE2 option takes a single argument which is
1927
** a pointer to an [sqlite3_pcache_methods2] object.  This object specifies
1928
** the interface to a custom page cache implementation.)^
1929
** ^SQLite makes a copy of the [sqlite3_pcache_methods2] object.</dd>
1930
**
1931
** [[SQLITE_CONFIG_GETPCACHE2]] <dt>SQLITE_CONFIG_GETPCACHE2</dt>
1932
** <dd> ^(The SQLITE_CONFIG_GETPCACHE2 option takes a single argument which
1933
** is a pointer to an [sqlite3_pcache_methods2] object.  SQLite copies of
1934
** the current page cache implementation into that object.)^ </dd>
1935
**
1936
** [[SQLITE_CONFIG_LOG]] <dt>SQLITE_CONFIG_LOG</dt>
1937
** <dd> The SQLITE_CONFIG_LOG option is used to configure the SQLite
1938
** global [error log].
1939
** (^The SQLITE_CONFIG_LOG option takes two arguments: a pointer to a
1940
** function with a call signature of void(*)(void*,int,const char*),
1941
** and a pointer to void. ^If the function pointer is not NULL, it is
1942
** invoked by [sqlite3_log()] to process each logging event.  ^If the
1943
** function pointer is NULL, the [sqlite3_log()] interface becomes a no-op.
1944
** ^The void pointer that is the second argument to SQLITE_CONFIG_LOG is
1945
** passed through as the first parameter to the application-defined logger
1946
** function whenever that function is invoked.  ^The second parameter to
1947
** the logger function is a copy of the first parameter to the corresponding
1948
** [sqlite3_log()] call and is intended to be a [result code] or an
1949
** [extended result code].  ^The third parameter passed to the logger is
1950
** log message after formatting via [sqlite3_snprintf()].
1951
** The SQLite logging interface is not reentrant; the logger function
1952
** supplied by the application must not invoke any SQLite interface.
1953
** In a multi-threaded application, the application-defined logger
1954
** function must be threadsafe. </dd>
1955
**
1956
** [[SQLITE_CONFIG_URI]] <dt>SQLITE_CONFIG_URI
1957
** <dd>^(The SQLITE_CONFIG_URI option takes a single argument of type int.
1958
** If non-zero, then URI handling is globally enabled. If the parameter is zero,
1959
** then URI handling is globally disabled.)^ ^If URI handling is globally
1960
** enabled, all filenames passed to [sqlite3_open()], [sqlite3_open_v2()],
1961
** [sqlite3_open16()] or
1962
** specified as part of [ATTACH] commands are interpreted as URIs, regardless
1963
** of whether or not the [SQLITE_OPEN_URI] flag is set when the database
1964
** connection is opened. ^If it is globally disabled, filenames are
1965
** only interpreted as URIs if the SQLITE_OPEN_URI flag is set when the
1966
** database connection is opened. ^(By default, URI handling is globally
1967
** disabled. The default value may be changed by compiling with the
1968
** [SQLITE_USE_URI] symbol defined.)^
1969
**
1970
** [[SQLITE_CONFIG_COVERING_INDEX_SCAN]] <dt>SQLITE_CONFIG_COVERING_INDEX_SCAN
1971
** <dd>^The SQLITE_CONFIG_COVERING_INDEX_SCAN option takes a single integer
1972
** argument which is interpreted as a boolean in order to enable or disable
1973
** the use of covering indices for full table scans in the query optimizer.
1974
** ^The default setting is determined
1975
** by the [SQLITE_ALLOW_COVERING_INDEX_SCAN] compile-time option, or is "on"
1976
** if that compile-time option is omitted.
1977
** The ability to disable the use of covering indices for full table scans
1978
** is because some incorrectly coded legacy applications might malfunction
1979
** when the optimization is enabled.  Providing the ability to
1980
** disable the optimization allows the older, buggy application code to work
1981
** without change even with newer versions of SQLite.
1982
**
1983
** [[SQLITE_CONFIG_PCACHE]] [[SQLITE_CONFIG_GETPCACHE]]
1984
** <dt>SQLITE_CONFIG_PCACHE and SQLITE_CONFIG_GETPCACHE
1985
** <dd> These options are obsolete and should not be used by new code.
1986
** They are retained for backwards compatibility but are now no-ops.
1987
** </dd>
1988
**
1989
** [[SQLITE_CONFIG_SQLLOG]]
1990
** <dt>SQLITE_CONFIG_SQLLOG
1991
** <dd>This option is only available if sqlite is compiled with the
1992
** [SQLITE_ENABLE_SQLLOG] pre-processor macro defined. The first argument should
1993
** be a pointer to a function of type void(*)(void*,sqlite3*,const char*, int).
1994
** The second should be of type (void*). The callback is invoked by the library
1995
** in three separate circumstances, identified by the value passed as the
1996
** fourth parameter. If the fourth parameter is 0, then the database connection
1997
** passed as the second argument has just been opened. The third argument
1998
** points to a buffer containing the name of the main database file. If the
1999
** fourth parameter is 1, then the SQL statement that the third parameter
2000
** points to has just been executed. Or, if the fourth parameter is 2, then
2001
** the connection being passed as the second parameter is being closed. The
2002
** third parameter is passed NULL In this case.  An example of using this
2003
** configuration option can be seen in the "test_sqllog.c" source file in
2004
** the canonical SQLite source tree.</dd>
2005
**
2006
** [[SQLITE_CONFIG_MMAP_SIZE]]
2007
** <dt>SQLITE_CONFIG_MMAP_SIZE
2008
** <dd>^SQLITE_CONFIG_MMAP_SIZE takes two 64-bit integer (sqlite3_int64) values
2009
** that are the default mmap size limit (the default setting for
2010
** [PRAGMA mmap_size]) and the maximum allowed mmap size limit.
2011
** ^The default setting can be overridden by each database connection using
2012
** either the [PRAGMA mmap_size] command, or by using the
2013
** [SQLITE_FCNTL_MMAP_SIZE] file control.  ^(The maximum allowed mmap size
2014
** will be silently truncated if necessary so that it does not exceed the
2015
** compile-time maximum mmap size set by the
2016
** [SQLITE_MAX_MMAP_SIZE] compile-time option.)^
2017
** ^If either argument to this option is negative, then that argument is
2018
** changed to its compile-time default.
2019
**
2020
** [[SQLITE_CONFIG_WIN32_HEAPSIZE]]
2021
** <dt>SQLITE_CONFIG_WIN32_HEAPSIZE
2022
** <dd>^The SQLITE_CONFIG_WIN32_HEAPSIZE option is only available if SQLite is
2023
** compiled for Windows with the [SQLITE_WIN32_MALLOC] pre-processor macro
2024
** defined. ^SQLITE_CONFIG_WIN32_HEAPSIZE takes a 32-bit unsigned integer value
2025
** that specifies the maximum size of the created heap.
2026
**
2027
** [[SQLITE_CONFIG_PCACHE_HDRSZ]]
2028
** <dt>SQLITE_CONFIG_PCACHE_HDRSZ
2029
** <dd>^The SQLITE_CONFIG_PCACHE_HDRSZ option takes a single parameter which
2030
** is a pointer to an integer and writes into that integer the number of extra
2031
** bytes per page required for each page in [SQLITE_CONFIG_PAGECACHE].
2032
** The amount of extra space required can change depending on the compiler,
2033
** target platform, and SQLite version.
2034
**
2035
** [[SQLITE_CONFIG_PMASZ]]
2036
** <dt>SQLITE_CONFIG_PMASZ
2037
** <dd>^The SQLITE_CONFIG_PMASZ option takes a single parameter which
2038
** is an unsigned integer and sets the "Minimum PMA Size" for the multithreaded
2039
** sorter to that integer.  The default minimum PMA Size is set by the
2040
** [SQLITE_SORTER_PMASZ] compile-time option.  New threads are launched
2041
** to help with sort operations when multithreaded sorting
2042
** is enabled (using the [PRAGMA threads] command) and the amount of content
2043
** to be sorted exceeds the page size times the minimum of the
2044
** [PRAGMA cache_size] setting and this value.
2045
**
2046
** [[SQLITE_CONFIG_STMTJRNL_SPILL]]
2047
** <dt>SQLITE_CONFIG_STMTJRNL_SPILL
2048
** <dd>^The SQLITE_CONFIG_STMTJRNL_SPILL option takes a single parameter which
2049
** becomes the [statement journal] spill-to-disk threshold.
2050
** [Statement journals] are held in memory until their size (in bytes)
2051
** exceeds this threshold, at which point they are written to disk.
2052
** Or if the threshold is -1, statement journals are always held
2053
** exclusively in memory.
2054
** Since many statement journals never become large, setting the spill
2055
** threshold to a value such as 64KiB can greatly reduce the amount of
2056
** I/O required to support statement rollback.
2057
** The default value for this setting is controlled by the
2058
** [SQLITE_STMTJRNL_SPILL] compile-time option.
2059
**
2060
** [[SQLITE_CONFIG_SORTERREF_SIZE]]
2061
** <dt>SQLITE_CONFIG_SORTERREF_SIZE
2062
** <dd>The SQLITE_CONFIG_SORTERREF_SIZE option accepts a single parameter
2063
** of type (int) - the new value of the sorter-reference size threshold.
2064
** Usually, when SQLite uses an external sort to order records according
2065
** to an ORDER BY clause, all fields required by the caller are present in the
2066
** sorted records. However, if SQLite determines based on the declared type
2067
** of a table column that its values are likely to be very large - larger
2068
** than the configured sorter-reference size threshold - then a reference
2069
** is stored in each sorted record and the required column values loaded
2070
** from the database as records are returned in sorted order. The default
2071
** value for this option is to never use this optimization. Specifying a
2072
** negative value for this option restores the default behaviour.
2073
** This option is only available if SQLite is compiled with the
2074
** [SQLITE_ENABLE_SORTER_REFERENCES] compile-time option.
2075
**
2076
** [[SQLITE_CONFIG_MEMDB_MAXSIZE]]
2077
** <dt>SQLITE_CONFIG_MEMDB_MAXSIZE
2078
** <dd>The SQLITE_CONFIG_MEMDB_MAXSIZE option accepts a single parameter
2079
** [sqlite3_int64] parameter which is the default maximum size for an in-memory
2080
** database created using [sqlite3_deserialize()].  This default maximum
2081
** size can be adjusted up or down for individual databases using the
2082
** [SQLITE_FCNTL_SIZE_LIMIT] [sqlite3_file_control|file-control].  If this
2083
** configuration setting is never used, then the default maximum is determined
2084
** by the [SQLITE_MEMDB_DEFAULT_MAXSIZE] compile-time option.  If that
2085
** compile-time option is not set, then the default maximum is 1073741824.
2086
** </dl>
2087
*/
2088
#define SQLITE_CONFIG_SINGLETHREAD  1  /* nil */
2089
#define SQLITE_CONFIG_MULTITHREAD   2  /* nil */
2090
#define SQLITE_CONFIG_SERIALIZED    3  /* nil */
2091
#define SQLITE_CONFIG_MALLOC        4  /* sqlite3_mem_methods* */
2092
#define SQLITE_CONFIG_GETMALLOC     5  /* sqlite3_mem_methods* */
2093
#define SQLITE_CONFIG_SCRATCH       6  /* No longer used */
2094
#define SQLITE_CONFIG_PAGECACHE     7  /* void*, int sz, int N */
2095
#define SQLITE_CONFIG_HEAP          8  /* void*, int nByte, int min */
2096
#define SQLITE_CONFIG_MEMSTATUS     9  /* boolean */
2097
#define SQLITE_CONFIG_MUTEX        10  /* sqlite3_mutex_methods* */
2098
#define SQLITE_CONFIG_GETMUTEX     11  /* sqlite3_mutex_methods* */
2099
/* previously SQLITE_CONFIG_CHUNKALLOC 12 which is now unused. */
2100
#define SQLITE_CONFIG_LOOKASIDE    13  /* int int */
2101
#define SQLITE_CONFIG_PCACHE       14  /* no-op */
2102
#define SQLITE_CONFIG_GETPCACHE    15  /* no-op */
2103
#define SQLITE_CONFIG_LOG          16  /* xFunc, void* */
2104
#define SQLITE_CONFIG_URI          17  /* int */
2105
#define SQLITE_CONFIG_PCACHE2      18  /* sqlite3_pcache_methods2* */
2106
#define SQLITE_CONFIG_GETPCACHE2   19  /* sqlite3_pcache_methods2* */
2107
#define SQLITE_CONFIG_COVERING_INDEX_SCAN 20  /* int */
2108
#define SQLITE_CONFIG_SQLLOG       21  /* xSqllog, void* */
2109
#define SQLITE_CONFIG_MMAP_SIZE    22  /* sqlite3_int64, sqlite3_int64 */
2110
#define SQLITE_CONFIG_WIN32_HEAPSIZE      23  /* int nByte */
2111
#define SQLITE_CONFIG_PCACHE_HDRSZ        24  /* int *psz */
2112
#define SQLITE_CONFIG_PMASZ               25  /* unsigned int szPma */
2113
#define SQLITE_CONFIG_STMTJRNL_SPILL      26  /* int nByte */
2114
#define SQLITE_CONFIG_SMALL_MALLOC        27  /* boolean */
2115
#define SQLITE_CONFIG_SORTERREF_SIZE      28  /* int nByte */
2116
#define SQLITE_CONFIG_MEMDB_MAXSIZE       29  /* sqlite3_int64 */
2117
2118
/*
2119
** CAPI3REF: Database Connection Configuration Options
2120
**
2121
** These constants are the available integer configuration options that
2122
** can be passed as the second argument to the [sqlite3_db_config()] interface.
2123
**
2124
** New configuration options may be added in future releases of SQLite.
2125
** Existing configuration options might be discontinued.  Applications
2126
** should check the return code from [sqlite3_db_config()] to make sure that
2127
** the call worked.  ^The [sqlite3_db_config()] interface will return a
2128
** non-zero [error code] if a discontinued or unsupported configuration option
2129
** is invoked.
2130
**
2131
** <dl>
2132
** [[SQLITE_DBCONFIG_LOOKASIDE]]
2133
** <dt>SQLITE_DBCONFIG_LOOKASIDE</dt>
2134
** <dd> ^This option takes three additional arguments that determine the
2135
** [lookaside memory allocator] configuration for the [database connection].
2136
** ^The first argument (the third parameter to [sqlite3_db_config()] is a
2137
** pointer to a memory buffer to use for lookaside memory.
2138
** ^The first argument after the SQLITE_DBCONFIG_LOOKASIDE verb
2139
** may be NULL in which case SQLite will allocate the
2140
** lookaside buffer itself using [sqlite3_malloc()]. ^The second argument is the
2141
** size of each lookaside buffer slot.  ^The third argument is the number of
2142
** slots.  The size of the buffer in the first argument must be greater than
2143
** or equal to the product of the second and third arguments.  The buffer
2144
** must be aligned to an 8-byte boundary.  ^If the second argument to
2145
** SQLITE_DBCONFIG_LOOKASIDE is not a multiple of 8, it is internally
2146
** rounded down to the next smaller multiple of 8.  ^(The lookaside memory
2147
** configuration for a database connection can only be changed when that
2148
** connection is not currently using lookaside memory, or in other words
2149
** when the "current value" returned by
2150
** [sqlite3_db_status](D,[SQLITE_CONFIG_LOOKASIDE],...) is zero.
2151
** Any attempt to change the lookaside memory configuration when lookaside
2152
** memory is in use leaves the configuration unchanged and returns
2153
** [SQLITE_BUSY].)^</dd>
2154
**
2155
** [[SQLITE_DBCONFIG_ENABLE_FKEY]]
2156
** <dt>SQLITE_DBCONFIG_ENABLE_FKEY</dt>
2157
** <dd> ^This option is used to enable or disable the enforcement of
2158
** [foreign key constraints].  There should be two additional arguments.
2159
** The first argument is an integer which is 0 to disable FK enforcement,
2160
** positive to enable FK enforcement or negative to leave FK enforcement
2161
** unchanged.  The second parameter is a pointer to an integer into which
2162
** is written 0 or 1 to indicate whether FK enforcement is off or on
2163
** following this call.  The second parameter may be a NULL pointer, in
2164
** which case the FK enforcement setting is not reported back. </dd>
2165
**
2166
** [[SQLITE_DBCONFIG_ENABLE_TRIGGER]]
2167
** <dt>SQLITE_DBCONFIG_ENABLE_TRIGGER</dt>
2168
** <dd> ^This option is used to enable or disable [CREATE TRIGGER | triggers].
2169
** There should be two additional arguments.
2170
** The first argument is an integer which is 0 to disable triggers,
2171
** positive to enable triggers or negative to leave the setting unchanged.
2172
** The second parameter is a pointer to an integer into which
2173
** is written 0 or 1 to indicate whether triggers are disabled or enabled
2174
** following this call.  The second parameter may be a NULL pointer, in
2175
** which case the trigger setting is not reported back.
2176
**
2177
** <p>Originally this option disabled all triggers.  ^(However, since
2178
** SQLite version 3.35.0, TEMP triggers are still allowed even if
2179
** this option is off.  So, in other words, this option now only disables
2180
** triggers in the main database schema or in the schemas of ATTACH-ed
2181
** databases.)^ </dd>
2182
**
2183
** [[SQLITE_DBCONFIG_ENABLE_VIEW]]
2184
** <dt>SQLITE_DBCONFIG_ENABLE_VIEW</dt>
2185
** <dd> ^This option is used to enable or disable [CREATE VIEW | views].
2186
** There should be two additional arguments.
2187
** The first argument is an integer which is 0 to disable views,
2188
** positive to enable views or negative to leave the setting unchanged.
2189
** The second parameter is a pointer to an integer into which
2190
** is written 0 or 1 to indicate whether views are disabled or enabled
2191
** following this call.  The second parameter may be a NULL pointer, in
2192
** which case the view setting is not reported back.
2193
**
2194
** <p>Originally this option disabled all views.  ^(However, since
2195
** SQLite version 3.35.0, TEMP views are still allowed even if
2196
** this option is off.  So, in other words, this option now only disables
2197
** views in the main database schema or in the schemas of ATTACH-ed
2198
** databases.)^ </dd>
2199
**
2200
** [[SQLITE_DBCONFIG_ENABLE_FTS3_TOKENIZER]]
2201
** <dt>SQLITE_DBCONFIG_ENABLE_FTS3_TOKENIZER</dt>
2202
** <dd> ^This option is used to enable or disable the
2203
** [fts3_tokenizer()] function which is part of the
2204
** [FTS3] full-text search engine extension.
2205
** There should be two additional arguments.
2206
** The first argument is an integer which is 0 to disable fts3_tokenizer() or
2207
** positive to enable fts3_tokenizer() or negative to leave the setting
2208
** unchanged.
2209
** The second parameter is a pointer to an integer into which
2210
** is written 0 or 1 to indicate whether fts3_tokenizer is disabled or enabled
2211
** following this call.  The second parameter may be a NULL pointer, in
2212
** which case the new setting is not reported back. </dd>
2213
**
2214
** [[SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION]]
2215
** <dt>SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION</dt>
2216
** <dd> ^This option is used to enable or disable the [sqlite3_load_extension()]
2217
** interface independently of the [load_extension()] SQL function.
2218
** The [sqlite3_enable_load_extension()] API enables or disables both the
2219
** C-API [sqlite3_load_extension()] and the SQL function [load_extension()].
2220
** There should be two additional arguments.
2221
** When the first argument to this interface is 1, then only the C-API is
2222
** enabled and the SQL function remains disabled.  If the first argument to
2223
** this interface is 0, then both the C-API and the SQL function are disabled.
2224
** If the first argument is -1, then no changes are made to state of either the
2225
** C-API or the SQL function.
2226
** The second parameter is a pointer to an integer into which
2227
** is written 0 or 1 to indicate whether [sqlite3_load_extension()] interface
2228
** is disabled or enabled following this call.  The second parameter may
2229
** be a NULL pointer, in which case the new setting is not reported back.
2230
** </dd>
2231
**
2232
** [[SQLITE_DBCONFIG_MAINDBNAME]] <dt>SQLITE_DBCONFIG_MAINDBNAME</dt>
2233
** <dd> ^This option is used to change the name of the "main" database
2234
** schema.  ^The sole argument is a pointer to a constant UTF8 string
2235
** which will become the new schema name in place of "main".  ^SQLite
2236
** does not make a copy of the new main schema name string, so the application
2237
** must ensure that the argument passed into this DBCONFIG option is unchanged
2238
** until after the database connection closes.
2239
** </dd>
2240
**
2241
** [[SQLITE_DBCONFIG_NO_CKPT_ON_CLOSE]]
2242
** <dt>SQLITE_DBCONFIG_NO_CKPT_ON_CLOSE</dt>
2243
** <dd> Usually, when a database in wal mode is closed or detached from a
2244
** database handle, SQLite checks if this will mean that there are now no
2245
** connections at all to the database. If so, it performs a checkpoint
2246
** operation before closing the connection. This option may be used to
2247
** override this behaviour. The first parameter passed to this operation
2248
** is an integer - positive to disable checkpoints-on-close, or zero (the
2249
** default) to enable them, and negative to leave the setting unchanged.
2250
** The second parameter is a pointer to an integer
2251
** into which is written 0 or 1 to indicate whether checkpoints-on-close
2252
** have been disabled - 0 if they are not disabled, 1 if they are.
2253
** </dd>
2254
**
2255
** [[SQLITE_DBCONFIG_ENABLE_QPSG]] <dt>SQLITE_DBCONFIG_ENABLE_QPSG</dt>
2256
** <dd>^(The SQLITE_DBCONFIG_ENABLE_QPSG option activates or deactivates
2257
** the [query planner stability guarantee] (QPSG).  When the QPSG is active,
2258
** a single SQL query statement will always use the same algorithm regardless
2259
** of values of [bound parameters].)^ The QPSG disables some query optimizations
2260
** that look at the values of bound parameters, which can make some queries
2261
** slower.  But the QPSG has the advantage of more predictable behavior.  With
2262
** the QPSG active, SQLite will always use the same query plan in the field as
2263
** was used during testing in the lab.
2264
** The first argument to this setting is an integer which is 0 to disable
2265
** the QPSG, positive to enable QPSG, or negative to leave the setting
2266
** unchanged. The second parameter is a pointer to an integer into which
2267
** is written 0 or 1 to indicate whether the QPSG is disabled or enabled
2268
** following this call.
2269
** </dd>
2270
**
2271
** [[SQLITE_DBCONFIG_TRIGGER_EQP]] <dt>SQLITE_DBCONFIG_TRIGGER_EQP</dt>
2272
** <dd> By default, the output of EXPLAIN QUERY PLAN commands does not
2273
** include output for any operations performed by trigger programs. This
2274
** option is used to set or clear (the default) a flag that governs this
2275
** behavior. The first parameter passed to this operation is an integer -
2276
** positive to enable output for trigger programs, or zero to disable it,
2277
** or negative to leave the setting unchanged.
2278
** The second parameter is a pointer to an integer into which is written
2279
** 0 or 1 to indicate whether output-for-triggers has been disabled - 0 if
2280
** it is not disabled, 1 if it is.
2281
** </dd>
2282
**
2283
** [[SQLITE_DBCONFIG_RESET_DATABASE]] <dt>SQLITE_DBCONFIG_RESET_DATABASE</dt>
2284
** <dd> Set the SQLITE_DBCONFIG_RESET_DATABASE flag and then run
2285
** [VACUUM] in order to reset a database back to an empty database
2286
** with no schema and no content. The following process works even for
2287
** a badly corrupted database file:
2288
** <ol>
2289
** <li> If the database connection is newly opened, make sure it has read the
2290
**      database schema by preparing then discarding some query against the
2291
**      database, or calling sqlite3_table_column_metadata(), ignoring any
2292
**      errors.  This step is only necessary if the application desires to keep
2293
**      the database in WAL mode after the reset if it was in WAL mode before
2294
**      the reset.
2295
** <li> sqlite3_db_config(db, SQLITE_DBCONFIG_RESET_DATABASE, 1, 0);
2296
** <li> [sqlite3_exec](db, "[VACUUM]", 0, 0, 0);
2297
** <li> sqlite3_db_config(db, SQLITE_DBCONFIG_RESET_DATABASE, 0, 0);
2298
** </ol>
2299
** Because resetting a database is destructive and irreversible, the
2300
** process requires the use of this obscure API and multiple steps to help
2301
** ensure that it does not happen by accident.
2302
**
2303
** [[SQLITE_DBCONFIG_DEFENSIVE]] <dt>SQLITE_DBCONFIG_DEFENSIVE</dt>
2304
** <dd>The SQLITE_DBCONFIG_DEFENSIVE option activates or deactivates the
2305
** "defensive" flag for a database connection.  When the defensive
2306
** flag is enabled, language features that allow ordinary SQL to
2307
** deliberately corrupt the database file are disabled.  The disabled
2308
** features include but are not limited to the following:
2309
** <ul>
2310
** <li> The [PRAGMA writable_schema=ON] statement.
2311
** <li> The [PRAGMA journal_mode=OFF] statement.
2312
** <li> Writes to the [sqlite_dbpage] virtual table.
2313
** <li> Direct writes to [shadow tables].
2314
** </ul>
2315
** </dd>
2316
**
2317
** [[SQLITE_DBCONFIG_WRITABLE_SCHEMA]] <dt>SQLITE_DBCONFIG_WRITABLE_SCHEMA</dt>
2318
** <dd>The SQLITE_DBCONFIG_WRITABLE_SCHEMA option activates or deactivates the
2319
** "writable_schema" flag. This has the same effect and is logically equivalent
2320
** to setting [PRAGMA writable_schema=ON] or [PRAGMA writable_schema=OFF].
2321
** The first argument to this setting is an integer which is 0 to disable
2322
** the writable_schema, positive to enable writable_schema, or negative to
2323
** leave the setting unchanged. The second parameter is a pointer to an
2324
** integer into which is written 0 or 1 to indicate whether the writable_schema
2325
** is enabled or disabled following this call.
2326
** </dd>
2327
**
2328
** [[SQLITE_DBCONFIG_LEGACY_ALTER_TABLE]]
2329
** <dt>SQLITE_DBCONFIG_LEGACY_ALTER_TABLE</dt>
2330
** <dd>The SQLITE_DBCONFIG_LEGACY_ALTER_TABLE option activates or deactivates
2331
** the legacy behavior of the [ALTER TABLE RENAME] command such it
2332
** behaves as it did prior to [version 3.24.0] (2018-06-04).  See the
2333
** "Compatibility Notice" on the [ALTER TABLE RENAME documentation] for
2334
** additional information. This feature can also be turned on and off
2335
** using the [PRAGMA legacy_alter_table] statement.
2336
** </dd>
2337
**
2338
** [[SQLITE_DBCONFIG_DQS_DML]]
2339
** <dt>SQLITE_DBCONFIG_DQS_DML</td>
2340
** <dd>The SQLITE_DBCONFIG_DQS_DML option activates or deactivates
2341
** the legacy [double-quoted string literal] misfeature for DML statements
2342
** only, that is DELETE, INSERT, SELECT, and UPDATE statements. The
2343
** default value of this setting is determined by the [-DSQLITE_DQS]
2344
** compile-time option.
2345
** </dd>
2346
**
2347
** [[SQLITE_DBCONFIG_DQS_DDL]]
2348
** <dt>SQLITE_DBCONFIG_DQS_DDL</td>
2349
** <dd>The SQLITE_DBCONFIG_DQS option activates or deactivates
2350
** the legacy [double-quoted string literal] misfeature for DDL statements,
2351
** such as CREATE TABLE and CREATE INDEX. The
2352
** default value of this setting is determined by the [-DSQLITE_DQS]
2353
** compile-time option.
2354
** </dd>
2355
**
2356
** [[SQLITE_DBCONFIG_TRUSTED_SCHEMA]]
2357
** <dt>SQLITE_DBCONFIG_TRUSTED_SCHEMA</td>
2358
** <dd>The SQLITE_DBCONFIG_TRUSTED_SCHEMA option tells SQLite to
2359
** assume that database schemas are untainted by malicious content.
2360
** When the SQLITE_DBCONFIG_TRUSTED_SCHEMA option is disabled, SQLite
2361
** takes additional defensive steps to protect the application from harm
2362
** including:
2363
** <ul>
2364
** <li> Prohibit the use of SQL functions inside triggers, views,
2365
** CHECK constraints, DEFAULT clauses, expression indexes,
2366
** partial indexes, or generated columns
2367
** unless those functions are tagged with [SQLITE_INNOCUOUS].
2368
** <li> Prohibit the use of virtual tables inside of triggers or views
2369
** unless those virtual tables are tagged with [SQLITE_VTAB_INNOCUOUS].
2370
** </ul>
2371
** This setting defaults to "on" for legacy compatibility, however
2372
** all applications are advised to turn it off if possible. This setting
2373
** can also be controlled using the [PRAGMA trusted_schema] statement.
2374
** </dd>
2375
**
2376
** [[SQLITE_DBCONFIG_LEGACY_FILE_FORMAT]]
2377
** <dt>SQLITE_DBCONFIG_LEGACY_FILE_FORMAT</td>
2378
** <dd>The SQLITE_DBCONFIG_LEGACY_FILE_FORMAT option activates or deactivates
2379
** the legacy file format flag.  When activated, this flag causes all newly
2380
** created database file to have a schema format version number (the 4-byte
2381
** integer found at offset 44 into the database header) of 1.  This in turn
2382
** means that the resulting database file will be readable and writable by
2383
** any SQLite version back to 3.0.0 ([dateof:3.0.0]).  Without this setting,
2384
** newly created databases are generally not understandable by SQLite versions
2385
** prior to 3.3.0 ([dateof:3.3.0]).  As these words are written, there
2386
** is now scarcely any need to generated database files that are compatible
2387
** all the way back to version 3.0.0, and so this setting is of little
2388
** practical use, but is provided so that SQLite can continue to claim the
2389
** ability to generate new database files that are compatible with  version
2390
** 3.0.0.
2391
** <p>Note that when the SQLITE_DBCONFIG_LEGACY_FILE_FORMAT setting is on,
2392
** the [VACUUM] command will fail with an obscure error when attempting to
2393
** process a table with generated columns and a descending index.  This is
2394
** not considered a bug since SQLite versions 3.3.0 and earlier do not support
2395
** either generated columns or decending indexes.
2396
** </dd>
2397
** </dl>
2398
*/
2399
#define SQLITE_DBCONFIG_MAINDBNAME            1000 /* const char* */
2400
#define SQLITE_DBCONFIG_LOOKASIDE             1001 /* void* int int */
2401
#define SQLITE_DBCONFIG_ENABLE_FKEY           1002 /* int int* */
2402
#define SQLITE_DBCONFIG_ENABLE_TRIGGER        1003 /* int int* */
2403
#define SQLITE_DBCONFIG_ENABLE_FTS3_TOKENIZER 1004 /* int int* */
2404
#define SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION 1005 /* int int* */
2405
#define SQLITE_DBCONFIG_NO_CKPT_ON_CLOSE      1006 /* int int* */
2406
#define SQLITE_DBCONFIG_ENABLE_QPSG           1007 /* int int* */
2407
#define SQLITE_DBCONFIG_TRIGGER_EQP           1008 /* int int* */
2408
#define SQLITE_DBCONFIG_RESET_DATABASE        1009 /* int int* */
2409
#define SQLITE_DBCONFIG_DEFENSIVE             1010 /* int int* */
2410
#define SQLITE_DBCONFIG_WRITABLE_SCHEMA       1011 /* int int* */
2411
#define SQLITE_DBCONFIG_LEGACY_ALTER_TABLE    1012 /* int int* */
2412
#define SQLITE_DBCONFIG_DQS_DML               1013 /* int int* */
2413
#define SQLITE_DBCONFIG_DQS_DDL               1014 /* int int* */
2414
#define SQLITE_DBCONFIG_ENABLE_VIEW           1015 /* int int* */
2415
#define SQLITE_DBCONFIG_LEGACY_FILE_FORMAT    1016 /* int int* */
2416
#define SQLITE_DBCONFIG_TRUSTED_SCHEMA        1017 /* int int* */
2417
#define SQLITE_DBCONFIG_MAX                   1017 /* Largest DBCONFIG */
2418
2419
/*
2420
** CAPI3REF: Enable Or Disable Extended Result Codes
2421
** METHOD: sqlite3
2422
**
2423
** ^The sqlite3_extended_result_codes() routine enables or disables the
2424
** [extended result codes] feature of SQLite. ^The extended result
2425
** codes are disabled by default for historical compatibility.
2426
*/
2427
SQLITE_API int sqlite3_extended_result_codes(sqlite3*, int onoff);
2428
2429
/*
2430
** CAPI3REF: Last Insert Rowid
2431
** METHOD: sqlite3
2432
**
2433
** ^Each entry in most SQLite tables (except for [WITHOUT ROWID] tables)
2434
** has a unique 64-bit signed
2435
** integer key called the [ROWID | "rowid"]. ^The rowid is always available
2436
** as an undeclared column named ROWID, OID, or _ROWID_ as long as those
2437
** names are not also used by explicitly declared columns. ^If
2438
** the table has a column of type [INTEGER PRIMARY KEY] then that column
2439
** is another alias for the rowid.
2440
**
2441
** ^The sqlite3_last_insert_rowid(D) interface usually returns the [rowid] of
2442
** the most recent successful [INSERT] into a rowid table or [virtual table]
2443
** on database connection D. ^Inserts into [WITHOUT ROWID] tables are not
2444
** recorded. ^If no successful [INSERT]s into rowid tables have ever occurred
2445
** on the database connection D, then sqlite3_last_insert_rowid(D) returns
2446
** zero.
2447
**
2448
** As well as being set automatically as rows are inserted into database
2449
** tables, the value returned by this function may be set explicitly by
2450
** [sqlite3_set_last_insert_rowid()]
2451
**
2452
** Some virtual table implementations may INSERT rows into rowid tables as
2453
** part of committing a transaction (e.g. to flush data accumulated in memory
2454
** to disk). In this case subsequent calls to this function return the rowid
2455
** associated with these internal INSERT operations, which leads to
2456
** unintuitive results. Virtual table implementations that do write to rowid
2457
** tables in this way can avoid this problem by restoring the original
2458
** rowid value using [sqlite3_set_last_insert_rowid()] before returning
2459
** control to the user.
2460
**
2461
** ^(If an [INSERT] occurs within a trigger then this routine will
2462
** return the [rowid] of the inserted row as long as the trigger is
2463
** running. Once the trigger program ends, the value returned
2464
** by this routine reverts to what it was before the trigger was fired.)^
2465
**
2466
** ^An [INSERT] that fails due to a constraint violation is not a
2467
** successful [INSERT] and does not change the value returned by this
2468
** routine.  ^Thus INSERT OR FAIL, INSERT OR IGNORE, INSERT OR ROLLBACK,
2469
** and INSERT OR ABORT make no changes to the return value of this
2470
** routine when their insertion fails.  ^(When INSERT OR REPLACE
2471
** encounters a constraint violation, it does not fail.  The
2472
** INSERT continues to completion after deleting rows that caused
2473
** the constraint problem so INSERT OR REPLACE will always change
2474
** the return value of this interface.)^
2475
**
2476
** ^For the purposes of this routine, an [INSERT] is considered to
2477
** be successful even if it is subsequently rolled back.
2478
**
2479
** This function is accessible to SQL statements via the
2480
** [last_insert_rowid() SQL function].
2481
**
2482
** If a separate thread performs a new [INSERT] on the same
2483
** database connection while the [sqlite3_last_insert_rowid()]
2484
** function is running and thus changes the last insert [rowid],
2485
** then the value returned by [sqlite3_last_insert_rowid()] is
2486
** unpredictable and might not equal either the old or the new
2487
** last insert [rowid].
2488
*/
2489
SQLITE_API sqlite3_int64 sqlite3_last_insert_rowid(sqlite3*);
2490
2491
/*
2492
** CAPI3REF: Set the Last Insert Rowid value.
2493
** METHOD: sqlite3
2494
**
2495
** The sqlite3_set_last_insert_rowid(D, R) method allows the application to
2496
** set the value returned by calling sqlite3_last_insert_rowid(D) to R
2497
** without inserting a row into the database.
2498
*/
2499
SQLITE_API void sqlite3_set_last_insert_rowid(sqlite3*,sqlite3_int64);
2500
2501
/*
2502
** CAPI3REF: Count The Number Of Rows Modified
2503
** METHOD: sqlite3
2504
**
2505
** ^These functions return the number of rows modified, inserted or
2506
** deleted by the most recently completed INSERT, UPDATE or DELETE
2507
** statement on the database connection specified by the only parameter.
2508
** The two functions are identical except for the type of the return value
2509
** and that if the number of rows modified by the most recent INSERT, UPDATE
2510
** or DELETE is greater than the maximum value supported by type "int", then
2511
** the return value of sqlite3_changes() is undefined. ^Executing any other
2512
** type of SQL statement does not modify the value returned by these functions.
2513
**
2514
** ^Only changes made directly by the INSERT, UPDATE or DELETE statement are
2515
** considered - auxiliary changes caused by [CREATE TRIGGER | triggers],
2516
** [foreign key actions] or [REPLACE] constraint resolution are not counted.
2517
**
2518
** Changes to a view that are intercepted by
2519
** [INSTEAD OF trigger | INSTEAD OF triggers] are not counted. ^The value
2520
** returned by sqlite3_changes() immediately after an INSERT, UPDATE or
2521
** DELETE statement run on a view is always zero. Only changes made to real
2522
** tables are counted.
2523
**
2524
** Things are more complicated if the sqlite3_changes() function is
2525
** executed while a trigger program is running. This may happen if the
2526
** program uses the [changes() SQL function], or if some other callback
2527
** function invokes sqlite3_changes() directly. Essentially:
2528
**
2529
** <ul>
2530
**   <li> ^(Before entering a trigger program the value returned by
2531
**        sqlite3_changes() function is saved. After the trigger program
2532
**        has finished, the original value is restored.)^
2533
**
2534
**   <li> ^(Within a trigger program each INSERT, UPDATE and DELETE
2535
**        statement sets the value returned by sqlite3_changes()
2536
**        upon completion as normal. Of course, this value will not include
2537
**        any changes performed by sub-triggers, as the sqlite3_changes()
2538
**        value will be saved and restored after each sub-trigger has run.)^
2539
** </ul>
2540
**
2541
** ^This means that if the changes() SQL function (or similar) is used
2542
** by the first INSERT, UPDATE or DELETE statement within a trigger, it
2543
** returns the value as set when the calling statement began executing.
2544
** ^If it is used by the second or subsequent such statement within a trigger
2545
** program, the value returned reflects the number of rows modified by the
2546
** previous INSERT, UPDATE or DELETE statement within the same trigger.
2547
**
2548
** If a separate thread makes changes on the same database connection
2549
** while [sqlite3_changes()] is running then the value returned
2550
** is unpredictable and not meaningful.
2551
**
2552
** See also:
2553
** <ul>
2554
** <li> the [sqlite3_total_changes()] interface
2555
** <li> the [count_changes pragma]
2556
** <li> the [changes() SQL function]
2557
** <li> the [data_version pragma]
2558
** </ul>
2559
*/
2560
SQLITE_API int sqlite3_changes(sqlite3*);
2561
SQLITE_API sqlite3_int64 sqlite3_changes64(sqlite3*);
2562
2563
/*
2564
** CAPI3REF: Total Number Of Rows Modified
2565
** METHOD: sqlite3
2566
**
2567
** ^These functions return the total number of rows inserted, modified or
2568
** deleted by all [INSERT], [UPDATE] or [DELETE] statements completed
2569
** since the database connection was opened, including those executed as
2570
** part of trigger programs. The two functions are identical except for the
2571
** type of the return value and that if the number of rows modified by the
2572
** connection exceeds the maximum value supported by type "int", then
2573
** the return value of sqlite3_total_changes() is undefined. ^Executing
2574
** any other type of SQL statement does not affect the value returned by
2575
** sqlite3_total_changes().
2576
**
2577
** ^Changes made as part of [foreign key actions] are included in the
2578
** count, but those made as part of REPLACE constraint resolution are
2579
** not. ^Changes to a view that are intercepted by INSTEAD OF triggers
2580
** are not counted.
2581
**
2582
** The [sqlite3_total_changes(D)] interface only reports the number
2583
** of rows that changed due to SQL statement run against database
2584
** connection D.  Any changes by other database connections are ignored.
2585
** To detect changes against a database file from other database
2586
** connections use the [PRAGMA data_version] command or the
2587
** [SQLITE_FCNTL_DATA_VERSION] [file control].
2588
**
2589
** If a separate thread makes changes on the same database connection
2590
** while [sqlite3_total_changes()] is running then the value
2591
** returned is unpredictable and not meaningful.
2592
**
2593
** See also:
2594
** <ul>
2595
** <li> the [sqlite3_changes()] interface
2596
** <li> the [count_changes pragma]
2597
** <li> the [changes() SQL function]
2598
** <li> the [data_version pragma]
2599
** <li> the [SQLITE_FCNTL_DATA_VERSION] [file control]
2600
** </ul>
2601
*/
2602
SQLITE_API int sqlite3_total_changes(sqlite3*);
2603
SQLITE_API sqlite3_int64 sqlite3_total_changes64(sqlite3*);
2604
2605
/*
2606
** CAPI3REF: Interrupt A Long-Running Query
2607
** METHOD: sqlite3
2608
**
2609
** ^This function causes any pending database operation to abort and
2610
** return at its earliest opportunity. This routine is typically
2611
** called in response to a user action such as pressing "Cancel"
2612
** or Ctrl-C where the user wants a long query operation to halt
2613
** immediately.
2614
**
2615
** ^It is safe to call this routine from a thread different from the
2616
** thread that is currently running the database operation.  But it
2617
** is not safe to call this routine with a [database connection] that
2618
** is closed or might close before sqlite3_interrupt() returns.
2619
**
2620
** ^If an SQL operation is very nearly finished at the time when
2621
** sqlite3_interrupt() is called, then it might not have an opportunity
2622
** to be interrupted and might continue to completion.
2623
**
2624
** ^An SQL operation that is interrupted will return [SQLITE_INTERRUPT].
2625
** ^If the interrupted SQL operation is an INSERT, UPDATE, or DELETE
2626
** that is inside an explicit transaction, then the entire transaction
2627
** will be rolled back automatically.
2628
**
2629
** ^The sqlite3_interrupt(D) call is in effect until all currently running
2630
** SQL statements on [database connection] D complete.  ^Any new SQL statements
2631
** that are started after the sqlite3_interrupt() call and before the
2632
** running statement count reaches zero are interrupted as if they had been
2633
** running prior to the sqlite3_interrupt() call.  ^New SQL statements
2634
** that are started after the running statement count reaches zero are
2635
** not effected by the sqlite3_interrupt().
2636
** ^A call to sqlite3_interrupt(D) that occurs when there are no running
2637
** SQL statements is a no-op and has no effect on SQL statements
2638
** that are started after the sqlite3_interrupt() call returns.
2639
*/
2640
SQLITE_API void sqlite3_interrupt(sqlite3*);
2641
2642
/*
2643
** CAPI3REF: Determine If An SQL Statement Is Complete
2644
**
2645
** These routines are useful during command-line input to determine if the
2646
** currently entered text seems to form a complete SQL statement or
2647
** if additional input is needed before sending the text into
2648
** SQLite for parsing.  ^These routines return 1 if the input string
2649
** appears to be a complete SQL statement.  ^A statement is judged to be
2650
** complete if it ends with a semicolon token and is not a prefix of a
2651
** well-formed CREATE TRIGGER statement.  ^Semicolons that are embedded within
2652
** string literals or quoted identifier names or comments are not
2653
** independent tokens (they are part of the token in which they are
2654
** embedded) and thus do not count as a statement terminator.  ^Whitespace
2655
** and comments that follow the final semicolon are ignored.
2656
**
2657
** ^These routines return 0 if the statement is incomplete.  ^If a
2658
** memory allocation fails, then SQLITE_NOMEM is returned.
2659
**
2660
** ^These routines do not parse the SQL statements thus
2661
** will not detect syntactically incorrect SQL.
2662
**
2663
** ^(If SQLite has not been initialized using [sqlite3_initialize()] prior
2664
** to invoking sqlite3_complete16() then sqlite3_initialize() is invoked
2665
** automatically by sqlite3_complete16().  If that initialization fails,
2666
** then the return value from sqlite3_complete16() will be non-zero
2667
** regardless of whether or not the input SQL is complete.)^
2668
**
2669
** The input to [sqlite3_complete()] must be a zero-terminated
2670
** UTF-8 string.
2671
**
2672
** The input to [sqlite3_complete16()] must be a zero-terminated
2673
** UTF-16 string in native byte order.
2674
*/
2675
SQLITE_API int sqlite3_complete(const char *sql);
2676
SQLITE_API int sqlite3_complete16(const void *sql);
2677
2678
/*
2679
** CAPI3REF: Register A Callback To Handle SQLITE_BUSY Errors
2680
** KEYWORDS: {busy-handler callback} {busy handler}
2681
** METHOD: sqlite3
2682
**
2683
** ^The sqlite3_busy_handler(D,X,P) routine sets a callback function X
2684
** that might be invoked with argument P whenever
2685
** an attempt is made to access a database table associated with
2686
** [database connection] D when another thread
2687
** or process has the table locked.
2688
** The sqlite3_busy_handler() interface is used to implement
2689
** [sqlite3_busy_timeout()] and [PRAGMA busy_timeout].
2690
**
2691
** ^If the busy callback is NULL, then [SQLITE_BUSY]
2692
** is returned immediately upon encountering the lock.  ^If the busy callback
2693
** is not NULL, then the callback might be invoked with two arguments.
2694
**
2695
** ^The first argument to the busy handler is a copy of the void* pointer which
2696
** is the third argument to sqlite3_busy_handler().  ^The second argument to
2697
** the busy handler callback is the number of times that the busy handler has
2698
** been invoked previously for the same locking event.  ^If the
2699
** busy callback returns 0, then no additional attempts are made to
2700
** access the database and [SQLITE_BUSY] is returned
2701
** to the application.
2702
** ^If the callback returns non-zero, then another attempt
2703
** is made to access the database and the cycle repeats.
2704
**
2705
** The presence of a busy handler does not guarantee that it will be invoked
2706
** when there is lock contention. ^If SQLite determines that invoking the busy
2707
** handler could result in a deadlock, it will go ahead and return [SQLITE_BUSY]
2708
** to the application instead of invoking the
2709
** busy handler.
2710
** Consider a scenario where one process is holding a read lock that
2711
** it is trying to promote to a reserved lock and
2712
** a second process is holding a reserved lock that it is trying
2713
** to promote to an exclusive lock.  The first process cannot proceed
2714
** because it is blocked by the second and the second process cannot
2715
** proceed because it is blocked by the first.  If both processes
2716
** invoke the busy handlers, neither will make any progress.  Therefore,
2717
** SQLite returns [SQLITE_BUSY] for the first process, hoping that this
2718
** will induce the first process to release its read lock and allow
2719
** the second process to proceed.
2720
**
2721
** ^The default busy callback is NULL.
2722
**
2723
** ^(There can only be a single busy handler defined for each
2724
** [database connection].  Setting a new busy handler clears any
2725
** previously set handler.)^  ^Note that calling [sqlite3_busy_timeout()]
2726
** or evaluating [PRAGMA busy_timeout=N] will change the
2727
** busy handler and thus clear any previously set busy handler.
2728
**
2729
** The busy callback should not take any actions which modify the
2730
** database connection that invoked the busy handler.  In other words,
2731
** the busy handler is not reentrant.  Any such actions
2732
** result in undefined behavior.
2733
**
2734
** A busy handler must not close the database connection
2735
** or [prepared statement] that invoked the busy handler.
2736
*/
2737
SQLITE_API int sqlite3_busy_handler(sqlite3*,int(*)(void*,int),void*);
2738
2739
/*
2740
** CAPI3REF: Set A Busy Timeout
2741
** METHOD: sqlite3
2742
**
2743
** ^This routine sets a [sqlite3_busy_handler | busy handler] that sleeps
2744
** for a specified amount of time when a table is locked.  ^The handler
2745
** will sleep multiple times until at least "ms" milliseconds of sleeping
2746
** have accumulated.  ^After at least "ms" milliseconds of sleeping,
2747
** the handler returns 0 which causes [sqlite3_step()] to return
2748
** [SQLITE_BUSY].
2749
**
2750
** ^Calling this routine with an argument less than or equal to zero
2751
** turns off all busy handlers.
2752
**
2753
** ^(There can only be a single busy handler for a particular
2754
** [database connection] at any given moment.  If another busy handler
2755
** was defined  (using [sqlite3_busy_handler()]) prior to calling
2756
** this routine, that other busy handler is cleared.)^
2757
**
2758
** See also:  [PRAGMA busy_timeout]
2759
*/
2760
SQLITE_API int sqlite3_busy_timeout(sqlite3*, int ms);
2761
2762
/*
2763
** CAPI3REF: Convenience Routines For Running Queries
2764
** METHOD: sqlite3
2765
**
2766
** This is a legacy interface that is preserved for backwards compatibility.
2767
** Use of this interface is not recommended.
2768
**
2769
** Definition: A <b>result table</b> is memory data structure created by the
2770
** [sqlite3_get_table()] interface.  A result table records the
2771
** complete query results from one or more queries.
2772
**
2773
** The table conceptually has a number of rows and columns.  But
2774
** these numbers are not part of the result table itself.  These
2775
** numbers are obtained separately.  Let N be the number of rows
2776
** and M be the number of columns.
2777
**
2778
** A result table is an array of pointers to zero-terminated UTF-8 strings.
2779
** There are (N+1)*M elements in the array.  The first M pointers point
2780
** to zero-terminated strings that  contain the names of the columns.
2781
** The remaining entries all point to query results.  NULL values result
2782
** in NULL pointers.  All other values are in their UTF-8 zero-terminated
2783
** string representation as returned by [sqlite3_column_text()].
2784
**
2785
** A result table might consist of one or more memory allocations.
2786
** It is not safe to pass a result table directly to [sqlite3_free()].
2787
** A result table should be deallocated using [sqlite3_free_table()].
2788
**
2789
** ^(As an example of the result table format, suppose a query result
2790
** is as follows:
2791
**
2792
** <blockquote><pre>
2793
**        Name        | Age
2794
**        -----------------------
2795
**        Alice       | 43
2796
**        Bob         | 28
2797
**        Cindy       | 21
2798
** </pre></blockquote>
2799
**
2800
** There are two columns (M==2) and three rows (N==3).  Thus the
2801
** result table has 8 entries.  Suppose the result table is stored
2802
** in an array named azResult.  Then azResult holds this content:
2803
**
2804
** <blockquote><pre>
2805
**        azResult&#91;0] = "Name";
2806
**        azResult&#91;1] = "Age";
2807
**        azResult&#91;2] = "Alice";
2808
**        azResult&#91;3] = "43";
2809
**        azResult&#91;4] = "Bob";
2810
**        azResult&#91;5] = "28";
2811
**        azResult&#91;6] = "Cindy";
2812
**        azResult&#91;7] = "21";
2813
** </pre></blockquote>)^
2814
**
2815
** ^The sqlite3_get_table() function evaluates one or more
2816
** semicolon-separated SQL statements in the zero-terminated UTF-8
2817
** string of its 2nd parameter and returns a result table to the
2818
** pointer given in its 3rd parameter.
2819
**
2820
** After the application has finished with the result from sqlite3_get_table(),
2821
** it must pass the result table pointer to sqlite3_free_table() in order to
2822
** release the memory that was malloced.  Because of the way the
2823
** [sqlite3_malloc()] happens within sqlite3_get_table(), the calling
2824
** function must not try to call [sqlite3_free()] directly.  Only
2825
** [sqlite3_free_table()] is able to release the memory properly and safely.
2826
**
2827
** The sqlite3_get_table() interface is implemented as a wrapper around
2828
** [sqlite3_exec()].  The sqlite3_get_table() routine does not have access
2829
** to any internal data structures of SQLite.  It uses only the public
2830
** interface defined here.  As a consequence, errors that occur in the
2831
** wrapper layer outside of the internal [sqlite3_exec()] call are not
2832
** reflected in subsequent calls to [sqlite3_errcode()] or
2833
** [sqlite3_errmsg()].
2834
*/
2835
SQLITE_API int sqlite3_get_table(
2836
  sqlite3 *db,          /* An open database */
2837
  const char *zSql,     /* SQL to be evaluated */
2838
  char ***pazResult,    /* Results of the query */
2839
  int *pnRow,           /* Number of result rows written here */
2840
  int *pnColumn,        /* Number of result columns written here */
2841
  char **pzErrmsg       /* Error msg written here */
2842
);
2843
SQLITE_API void sqlite3_free_table(char **result);
2844
2845
/*
2846
** CAPI3REF: Formatted String Printing Functions
2847
**
2848
** These routines are work-alikes of the "printf()" family of functions
2849
** from the standard C library.
2850
** These routines understand most of the common formatting options from
2851
** the standard library printf()
2852
** plus some additional non-standard formats ([%q], [%Q], [%w], and [%z]).
2853
** See the [built-in printf()] documentation for details.
2854
**
2855
** ^The sqlite3_mprintf() and sqlite3_vmprintf() routines write their
2856
** results into memory obtained from [sqlite3_malloc64()].
2857
** The strings returned by these two routines should be
2858
** released by [sqlite3_free()].  ^Both routines return a
2859
** NULL pointer if [sqlite3_malloc64()] is unable to allocate enough
2860
** memory to hold the resulting string.
2861
**
2862
** ^(The sqlite3_snprintf() routine is similar to "snprintf()" from
2863
** the standard C library.  The result is written into the
2864
** buffer supplied as the second parameter whose size is given by
2865
** the first parameter. Note that the order of the
2866
** first two parameters is reversed from snprintf().)^  This is an
2867
** historical accident that cannot be fixed without breaking
2868
** backwards compatibility.  ^(Note also that sqlite3_snprintf()
2869
** returns a pointer to its buffer instead of the number of
2870
** characters actually written into the buffer.)^  We admit that
2871
** the number of characters written would be a more useful return
2872
** value but we cannot change the implementation of sqlite3_snprintf()
2873
** now without breaking compatibility.
2874
**
2875
** ^As long as the buffer size is greater than zero, sqlite3_snprintf()
2876
** guarantees that the buffer is always zero-terminated.  ^The first
2877
** parameter "n" is the total size of the buffer, including space for
2878
** the zero terminator.  So the longest string that can be completely
2879
** written will be n-1 characters.
2880
**
2881
** ^The sqlite3_vsnprintf() routine is a varargs version of sqlite3_snprintf().
2882
**
2883
** See also:  [built-in printf()], [printf() SQL function]
2884
*/
2885
SQLITE_API char *sqlite3_mprintf(const char*,...);
2886
SQLITE_API char *sqlite3_vmprintf(const char*, va_list);
2887
SQLITE_API char *sqlite3_snprintf(int,char*,const char*, ...);
2888
SQLITE_API char *sqlite3_vsnprintf(int,char*,const char*, va_list);
2889
2890
/*
2891
** CAPI3REF: Memory Allocation Subsystem
2892
**
2893
** The SQLite core uses these three routines for all of its own
2894
** internal memory allocation needs. "Core" in the previous sentence
2895
** does not include operating-system specific [VFS] implementation.  The
2896
** Windows VFS uses native malloc() and free() for some operations.
2897
**
2898
** ^The sqlite3_malloc() routine returns a pointer to a block
2899
** of memory at least N bytes in length, where N is the parameter.
2900
** ^If sqlite3_malloc() is unable to obtain sufficient free
2901
** memory, it returns a NULL pointer.  ^If the parameter N to
2902
** sqlite3_malloc() is zero or negative then sqlite3_malloc() returns
2903
** a NULL pointer.
2904
**
2905
** ^The sqlite3_malloc64(N) routine works just like
2906
** sqlite3_malloc(N) except that N is an unsigned 64-bit integer instead
2907
** of a signed 32-bit integer.
2908
**
2909
** ^Calling sqlite3_free() with a pointer previously returned
2910
** by sqlite3_malloc() or sqlite3_realloc() releases that memory so
2911
** that it might be reused.  ^The sqlite3_free() routine is
2912
** a no-op if is called with a NULL pointer.  Passing a NULL pointer
2913
** to sqlite3_free() is harmless.  After being freed, memory
2914
** should neither be read nor written.  Even reading previously freed
2915
** memory might result in a segmentation fault or other severe error.
2916
** Memory corruption, a segmentation fault, or other severe error
2917
** might result if sqlite3_free() is called with a non-NULL pointer that
2918
** was not obtained from sqlite3_malloc() or sqlite3_realloc().
2919
**
2920
** ^The sqlite3_realloc(X,N) interface attempts to resize a
2921
** prior memory allocation X to be at least N bytes.
2922
** ^If the X parameter to sqlite3_realloc(X,N)
2923
** is a NULL pointer then its behavior is identical to calling
2924
** sqlite3_malloc(N).
2925
** ^If the N parameter to sqlite3_realloc(X,N) is zero or
2926
** negative then the behavior is exactly the same as calling
2927
** sqlite3_free(X).
2928
** ^sqlite3_realloc(X,N) returns a pointer to a memory allocation
2929
** of at least N bytes in size or NULL if insufficient memory is available.
2930
** ^If M is the size of the prior allocation, then min(N,M) bytes
2931
** of the prior allocation are copied into the beginning of buffer returned
2932
** by sqlite3_realloc(X,N) and the prior allocation is freed.
2933
** ^If sqlite3_realloc(X,N) returns NULL and N is positive, then the
2934
** prior allocation is not freed.
2935
**
2936
** ^The sqlite3_realloc64(X,N) interfaces works the same as
2937
** sqlite3_realloc(X,N) except that N is a 64-bit unsigned integer instead
2938
** of a 32-bit signed integer.
2939
**
2940
** ^If X is a memory allocation previously obtained from sqlite3_malloc(),
2941
** sqlite3_malloc64(), sqlite3_realloc(), or sqlite3_realloc64(), then
2942
** sqlite3_msize(X) returns the size of that memory allocation in bytes.
2943
** ^The value returned by sqlite3_msize(X) might be larger than the number
2944
** of bytes requested when X was allocated.  ^If X is a NULL pointer then
2945
** sqlite3_msize(X) returns zero.  If X points to something that is not
2946
** the beginning of memory allocation, or if it points to a formerly
2947
** valid memory allocation that has now been freed, then the behavior
2948
** of sqlite3_msize(X) is undefined and possibly harmful.
2949
**
2950
** ^The memory returned by sqlite3_malloc(), sqlite3_realloc(),
2951
** sqlite3_malloc64(), and sqlite3_realloc64()
2952
** is always aligned to at least an 8 byte boundary, or to a
2953
** 4 byte boundary if the [SQLITE_4_BYTE_ALIGNED_MALLOC] compile-time
2954
** option is used.
2955
**
2956
** The pointer arguments to [sqlite3_free()] and [sqlite3_realloc()]
2957
** must be either NULL or else pointers obtained from a prior
2958
** invocation of [sqlite3_malloc()] or [sqlite3_realloc()] that have
2959
** not yet been released.
2960
**
2961
** The application must not read or write any part of
2962
** a block of memory after it has been released using
2963
** [sqlite3_free()] or [sqlite3_realloc()].
2964
*/
2965
SQLITE_API void *sqlite3_malloc(int);
2966
SQLITE_API void *sqlite3_malloc64(sqlite3_uint64);
2967
SQLITE_API void *sqlite3_realloc(void*, int);
2968
SQLITE_API void *sqlite3_realloc64(void*, sqlite3_uint64);
2969
SQLITE_API void sqlite3_free(void*);
2970
SQLITE_API sqlite3_uint64 sqlite3_msize(void*);
2971
2972
/*
2973
** CAPI3REF: Memory Allocator Statistics
2974
**
2975
** SQLite provides these two interfaces for reporting on the status
2976
** of the [sqlite3_malloc()], [sqlite3_free()], and [sqlite3_realloc()]
2977
** routines, which form the built-in memory allocation subsystem.
2978
**
2979
** ^The [sqlite3_memory_used()] routine returns the number of bytes
2980
** of memory currently outstanding (malloced but not freed).
2981
** ^The [sqlite3_memory_highwater()] routine returns the maximum
2982
** value of [sqlite3_memory_used()] since the high-water mark
2983
** was last reset.  ^The values returned by [sqlite3_memory_used()] and
2984
** [sqlite3_memory_highwater()] include any overhead
2985
** added by SQLite in its implementation of [sqlite3_malloc()],
2986
** but not overhead added by the any underlying system library
2987
** routines that [sqlite3_malloc()] may call.
2988
**
2989
** ^The memory high-water mark is reset to the current value of
2990
** [sqlite3_memory_used()] if and only if the parameter to
2991
** [sqlite3_memory_highwater()] is true.  ^The value returned
2992
** by [sqlite3_memory_highwater(1)] is the high-water mark
2993
** prior to the reset.
2994
*/
2995
SQLITE_API sqlite3_int64 sqlite3_memory_used(void);
2996
SQLITE_API sqlite3_int64 sqlite3_memory_highwater(int resetFlag);
2997
2998
/*
2999
** CAPI3REF: Pseudo-Random Number Generator
3000
**
3001
** SQLite contains a high-quality pseudo-random number generator (PRNG) used to
3002
** select random [ROWID | ROWIDs] when inserting new records into a table that
3003
** already uses the largest possible [ROWID].  The PRNG is also used for
3004
** the built-in random() and randomblob() SQL functions.  This interface allows
3005
** applications to access the same PRNG for other purposes.
3006
**
3007
** ^A call to this routine stores N bytes of randomness into buffer P.
3008
** ^The P parameter can be a NULL pointer.
3009
**
3010
** ^If this routine has not been previously called or if the previous
3011
** call had N less than one or a NULL pointer for P, then the PRNG is
3012
** seeded using randomness obtained from the xRandomness method of
3013
** the default [sqlite3_vfs] object.
3014
** ^If the previous call to this routine had an N of 1 or more and a
3015
** non-NULL P then the pseudo-randomness is generated
3016
** internally and without recourse to the [sqlite3_vfs] xRandomness
3017
** method.
3018
*/
3019
SQLITE_API void sqlite3_randomness(int N, void *P);
3020
3021
/*
3022
** CAPI3REF: Compile-Time Authorization Callbacks
3023
** METHOD: sqlite3
3024
** KEYWORDS: {authorizer callback}
3025
**
3026
** ^This routine registers an authorizer callback with a particular
3027
** [database connection], supplied in the first argument.
3028
** ^The authorizer callback is invoked as SQL statements are being compiled
3029
** by [sqlite3_prepare()] or its variants [sqlite3_prepare_v2()],
3030
** [sqlite3_prepare_v3()], [sqlite3_prepare16()], [sqlite3_prepare16_v2()],
3031
** and [sqlite3_prepare16_v3()].  ^At various
3032
** points during the compilation process, as logic is being created
3033
** to perform various actions, the authorizer callback is invoked to
3034
** see if those actions are allowed.  ^The authorizer callback should
3035
** return [SQLITE_OK] to allow the action, [SQLITE_IGNORE] to disallow the
3036
** specific action but allow the SQL statement to continue to be
3037
** compiled, or [SQLITE_DENY] to cause the entire SQL statement to be
3038
** rejected with an error.  ^If the authorizer callback returns
3039
** any value other than [SQLITE_IGNORE], [SQLITE_OK], or [SQLITE_DENY]
3040
** then the [sqlite3_prepare_v2()] or equivalent call that triggered
3041
** the authorizer will fail with an error message.
3042
**
3043
** When the callback returns [SQLITE_OK], that means the operation
3044
** requested is ok.  ^When the callback returns [SQLITE_DENY], the
3045
** [sqlite3_prepare_v2()] or equivalent call that triggered the
3046
** authorizer will fail with an error message explaining that
3047
** access is denied.
3048
**
3049
** ^The first parameter to the authorizer callback is a copy of the third
3050
** parameter to the sqlite3_set_authorizer() interface. ^The second parameter
3051
** to the callback is an integer [SQLITE_COPY | action code] that specifies
3052
** the particular action to be authorized. ^The third through sixth parameters
3053
** to the callback are either NULL pointers or zero-terminated strings
3054
** that contain additional details about the action to be authorized.
3055
** Applications must always be prepared to encounter a NULL pointer in any
3056
** of the third through the sixth parameters of the authorization callback.
3057
**
3058
** ^If the action code is [SQLITE_READ]
3059
** and the callback returns [SQLITE_IGNORE] then the
3060
** [prepared statement] statement is constructed to substitute
3061
** a NULL value in place of the table column that would have
3062
** been read if [SQLITE_OK] had been returned.  The [SQLITE_IGNORE]
3063
** return can be used to deny an untrusted user access to individual
3064
** columns of a table.
3065
** ^When a table is referenced by a [SELECT] but no column values are
3066
** extracted from that table (for example in a query like
3067
** "SELECT count(*) FROM tab") then the [SQLITE_READ] authorizer callback
3068
** is invoked once for that table with a column name that is an empty string.
3069
** ^If the action code is [SQLITE_DELETE] and the callback returns
3070
** [SQLITE_IGNORE] then the [DELETE] operation proceeds but the
3071
** [truncate optimization] is disabled and all rows are deleted individually.
3072
**
3073
** An authorizer is used when [sqlite3_prepare | preparing]
3074
** SQL statements from an untrusted source, to ensure that the SQL statements
3075
** do not try to access data they are not allowed to see, or that they do not
3076
** try to execute malicious statements that damage the database.  For
3077
** example, an application may allow a user to enter arbitrary
3078
** SQL queries for evaluation by a database.  But the application does
3079
** not want the user to be able to make arbitrary changes to the
3080
** database.  An authorizer could then be put in place while the
3081
** user-entered SQL is being [sqlite3_prepare | prepared] that
3082
** disallows everything except [SELECT] statements.
3083
**
3084
** Applications that need to process SQL from untrusted sources
3085
** might also consider lowering resource limits using [sqlite3_limit()]
3086
** and limiting database size using the [max_page_count] [PRAGMA]
3087
** in addition to using an authorizer.
3088
**
3089
** ^(Only a single authorizer can be in place on a database connection
3090
** at a time.  Each call to sqlite3_set_authorizer overrides the
3091
** previous call.)^  ^Disable the authorizer by installing a NULL callback.
3092
** The authorizer is disabled by default.
3093
**
3094
** The authorizer callback must not do anything that will modify
3095
** the database connection that invoked the authorizer callback.
3096
** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
3097
** database connections for the meaning of "modify" in this paragraph.
3098
**
3099
** ^When [sqlite3_prepare_v2()] is used to prepare a statement, the
3100
** statement might be re-prepared during [sqlite3_step()] due to a
3101
** schema change.  Hence, the application should ensure that the
3102
** correct authorizer callback remains in place during the [sqlite3_step()].
3103
**
3104
** ^Note that the authorizer callback is invoked only during
3105
** [sqlite3_prepare()] or its variants.  Authorization is not
3106
** performed during statement evaluation in [sqlite3_step()], unless
3107
** as stated in the previous paragraph, sqlite3_step() invokes
3108
** sqlite3_prepare_v2() to reprepare a statement after a schema change.
3109
*/
3110
SQLITE_API int sqlite3_set_authorizer(
3111
  sqlite3*,
3112
  int (*xAuth)(void*,int,const char*,const char*,const char*,const char*),
3113
  void *pUserData
3114
);
3115
3116
/*
3117
** CAPI3REF: Authorizer Return Codes
3118
**
3119
** The [sqlite3_set_authorizer | authorizer callback function] must
3120
** return either [SQLITE_OK] or one of these two constants in order
3121
** to signal SQLite whether or not the action is permitted.  See the
3122
** [sqlite3_set_authorizer | authorizer documentation] for additional
3123
** information.
3124
**
3125
** Note that SQLITE_IGNORE is also used as a [conflict resolution mode]
3126
** returned from the [sqlite3_vtab_on_conflict()] interface.
3127
*/
3128
29
#define SQLITE_DENY   1   /* Abort the SQL statement with an error */
3129
#define SQLITE_IGNORE 2   /* Don't allow access, but don't generate an error */
3130
3131
/*
3132
** CAPI3REF: Authorizer Action Codes
3133
**
3134
** The [sqlite3_set_authorizer()] interface registers a callback function
3135
** that is invoked to authorize certain SQL statement actions.  The
3136
** second parameter to the callback is an integer code that specifies
3137
** what action is being authorized.  These are the integer action codes that
3138
** the authorizer callback may be passed.
3139
**
3140
** These action code values signify what kind of operation is to be
3141
** authorized.  The 3rd and 4th parameters to the authorization
3142
** callback function will be parameters or NULL depending on which of these
3143
** codes is used as the second parameter.  ^(The 5th parameter to the
3144
** authorizer callback is the name of the database ("main", "temp",
3145
** etc.) if applicable.)^  ^The 6th parameter to the authorizer callback
3146
** is the name of the inner-most trigger or view that is responsible for
3147
** the access attempt or NULL if this access attempt is directly from
3148
** top-level SQL code.
3149
*/
3150
/******************************************* 3rd ************ 4th ***********/
3151
#define SQLITE_CREATE_INDEX          1   /* Index Name      Table Name      */
3152
#define SQLITE_CREATE_TABLE          2   /* Table Name      NULL            */
3153
#define SQLITE_CREATE_TEMP_INDEX     3   /* Index Name      Table Name      */
3154
#define SQLITE_CREATE_TEMP_TABLE     4   /* Table Name      NULL            */
3155
#define SQLITE_CREATE_TEMP_TRIGGER   5   /* Trigger Name    Table Name      */
3156
#define SQLITE_CREATE_TEMP_VIEW      6   /* View Name       NULL            */
3157
#define SQLITE_CREATE_TRIGGER        7   /* Trigger Name    Table Name      */
3158
#define SQLITE_CREATE_VIEW           8   /* View Name       NULL            */
3159
#define SQLITE_DELETE                9   /* Table Name      NULL            */
3160
#define SQLITE_DROP_INDEX           10   /* Index Name      Table Name      */
3161
#define SQLITE_DROP_TABLE           11   /* Table Name      NULL            */
3162
#define SQLITE_DROP_TEMP_INDEX      12   /* Index Name      Table Name      */
3163
#define SQLITE_DROP_TEMP_TABLE      13   /* Table Name      NULL            */
3164
#define SQLITE_DROP_TEMP_TRIGGER    14   /* Trigger Name    Table Name      */
3165
#define SQLITE_DROP_TEMP_VIEW       15   /* View Name       NULL            */
3166
#define SQLITE_DROP_TRIGGER         16   /* Trigger Name    Table Name      */
3167
#define SQLITE_DROP_VIEW            17   /* View Name       NULL            */
3168
#define SQLITE_INSERT               18   /* Table Name      NULL            */
3169
#define SQLITE_PRAGMA               19   /* Pragma Name     1st arg or NULL */
3170
#define SQLITE_READ                 20   /* Table Name      Column Name     */
3171
#define SQLITE_SELECT               21   /* NULL            NULL            */
3172
#define SQLITE_TRANSACTION          22   /* Operation       NULL            */
3173
#define SQLITE_UPDATE               23   /* Table Name      Column Name     */
3174
#define SQLITE_ATTACH               24   /* Filename        NULL            */
3175
#define SQLITE_DETACH               25   /* Database Name   NULL            */
3176
#define SQLITE_ALTER_TABLE          26   /* Database Name   Table Name      */
3177
#define SQLITE_REINDEX              27   /* Index Name      NULL            */
3178
#define SQLITE_ANALYZE              28   /* Table Name      NULL            */
3179
#define SQLITE_CREATE_VTABLE        29   /* Table Name      Module Name     */
3180
#define SQLITE_DROP_VTABLE          30   /* Table Name      Module Name     */
3181
#define SQLITE_FUNCTION             31   /* NULL            Function Name   */
3182
#define SQLITE_SAVEPOINT            32   /* Operation       Savepoint Name  */
3183
#define SQLITE_COPY                  0   /* No longer used */
3184
#define SQLITE_RECURSIVE            33   /* NULL            NULL            */
3185
3186
/*
3187
** CAPI3REF: Tracing And Profiling Functions
3188
** METHOD: sqlite3
3189
**
3190
** These routines are deprecated. Use the [sqlite3_trace_v2()] interface
3191
** instead of the routines described here.
3192
**
3193
** These routines register callback functions that can be used for
3194
** tracing and profiling the execution of SQL statements.
3195
**
3196
** ^The callback function registered by sqlite3_trace() is invoked at
3197
** various times when an SQL statement is being run by [sqlite3_step()].
3198
** ^The sqlite3_trace() callback is invoked with a UTF-8 rendering of the
3199
** SQL statement text as the statement first begins executing.
3200
** ^(Additional sqlite3_trace() callbacks might occur
3201
** as each triggered subprogram is entered.  The callbacks for triggers
3202
** contain a UTF-8 SQL comment that identifies the trigger.)^
3203
**
3204
** The [SQLITE_TRACE_SIZE_LIMIT] compile-time option can be used to limit
3205
** the length of [bound parameter] expansion in the output of sqlite3_trace().
3206
**
3207
** ^The callback function registered by sqlite3_profile() is invoked
3208
** as each SQL statement finishes.  ^The profile callback contains
3209
** the original statement text and an estimate of wall-clock time
3210
** of how long that statement took to run.  ^The profile callback
3211
** time is in units of nanoseconds, however the current implementation
3212
** is only capable of millisecond resolution so the six least significant
3213
** digits in the time are meaningless.  Future versions of SQLite
3214
** might provide greater resolution on the profiler callback.  Invoking
3215
** either [sqlite3_trace()] or [sqlite3_trace_v2()] will cancel the
3216
** profile callback.
3217
*/
3218
SQLITE_API SQLITE_DEPRECATED void *sqlite3_trace(sqlite3*,
3219
   void(*xTrace)(void*,const char*), void*);
3220
SQLITE_API SQLITE_DEPRECATED void *sqlite3_profile(sqlite3*,
3221
   void(*xProfile)(void*,const char*,sqlite3_uint64), void*);
3222
3223
/*
3224
** CAPI3REF: SQL Trace Event Codes
3225
** KEYWORDS: SQLITE_TRACE
3226
**
3227
** These constants identify classes of events that can be monitored
3228
** using the [sqlite3_trace_v2()] tracing logic.  The M argument
3229
** to [sqlite3_trace_v2(D,M,X,P)] is an OR-ed combination of one or more of
3230
** the following constants.  ^The first argument to the trace callback
3231
** is one of the following constants.
3232
**
3233
** New tracing constants may be added in future releases.
3234
**
3235
** ^A trace callback has four arguments: xCallback(T,C,P,X).
3236
** ^The T argument is one of the integer type codes above.
3237
** ^The C argument is a copy of the context pointer passed in as the
3238
** fourth argument to [sqlite3_trace_v2()].
3239
** The P and X arguments are pointers whose meanings depend on T.
3240
**
3241
** <dl>
3242
** [[SQLITE_TRACE_STMT]] <dt>SQLITE_TRACE_STMT</dt>
3243
** <dd>^An SQLITE_TRACE_STMT callback is invoked when a prepared statement
3244
** first begins running and possibly at other times during the
3245
** execution of the prepared statement, such as at the start of each
3246
** trigger subprogram. ^The P argument is a pointer to the
3247
** [prepared statement]. ^The X argument is a pointer to a string which
3248
** is the unexpanded SQL text of the prepared statement or an SQL comment
3249
** that indicates the invocation of a trigger.  ^The callback can compute
3250
** the same text that would have been returned by the legacy [sqlite3_trace()]
3251
** interface by using the X argument when X begins with "--" and invoking
3252
** [sqlite3_expanded_sql(P)] otherwise.
3253
**
3254
** [[SQLITE_TRACE_PROFILE]] <dt>SQLITE_TRACE_PROFILE</dt>
3255
** <dd>^An SQLITE_TRACE_PROFILE callback provides approximately the same
3256
** information as is provided by the [sqlite3_profile()] callback.
3257
** ^The P argument is a pointer to the [prepared statement] and the
3258
** X argument points to a 64-bit integer which is the estimated of
3259
** the number of nanosecond that the prepared statement took to run.
3260
** ^The SQLITE_TRACE_PROFILE callback is invoked when the statement finishes.
3261
**
3262
** [[SQLITE_TRACE_ROW]] <dt>SQLITE_TRACE_ROW</dt>
3263
** <dd>^An SQLITE_TRACE_ROW callback is invoked whenever a prepared
3264
** statement generates a single row of result.
3265
** ^The P argument is a pointer to the [prepared statement] and the
3266
** X argument is unused.
3267
**
3268
** [[SQLITE_TRACE_CLOSE]] <dt>SQLITE_TRACE_CLOSE</dt>
3269
** <dd>^An SQLITE_TRACE_CLOSE callback is invoked when a database
3270
** connection closes.
3271
** ^The P argument is a pointer to the [database connection] object
3272
** and the X argument is unused.
3273
** </dl>
3274
*/
3275
84
#define SQLITE_TRACE_STMT       0x01
3276
#define SQLITE_TRACE_PROFILE    0x02
3277
#define SQLITE_TRACE_ROW        0x04
3278
#define SQLITE_TRACE_CLOSE      0x08
3279
3280
/*
3281
** CAPI3REF: SQL Trace Hook
3282
** METHOD: sqlite3
3283
**
3284
** ^The sqlite3_trace_v2(D,M,X,P) interface registers a trace callback
3285
** function X against [database connection] D, using property mask M
3286
** and context pointer P.  ^If the X callback is
3287
** NULL or if the M mask is zero, then tracing is disabled.  The
3288
** M argument should be the bitwise OR-ed combination of
3289
** zero or more [SQLITE_TRACE] constants.
3290
**
3291
** ^Each call to either sqlite3_trace() or sqlite3_trace_v2() overrides
3292
** (cancels) any prior calls to sqlite3_trace() or sqlite3_trace_v2().
3293
**
3294
** ^The X callback is invoked whenever any of the events identified by
3295
** mask M occur.  ^The integer return value from the callback is currently
3296
** ignored, though this may change in future releases.  Callback
3297
** implementations should return zero to ensure future compatibility.
3298
**
3299
** ^A trace callback is invoked with four arguments: callback(T,C,P,X).
3300
** ^The T argument is one of the [SQLITE_TRACE]
3301
** constants to indicate why the callback was invoked.
3302
** ^The C argument is a copy of the context pointer.
3303
** The P and X arguments are pointers whose meanings depend on T.
3304
**
3305
** The sqlite3_trace_v2() interface is intended to replace the legacy
3306
** interfaces [sqlite3_trace()] and [sqlite3_profile()], both of which
3307
** are deprecated.
3308
*/
3309
SQLITE_API int sqlite3_trace_v2(
3310
  sqlite3*,
3311
  unsigned uMask,
3312
  int(*xCallback)(unsigned,void*,void*,void*),
3313
  void *pCtx
3314
);
3315
3316
/*
3317
** CAPI3REF: Query Progress Callbacks
3318
** METHOD: sqlite3
3319
**
3320
** ^The sqlite3_progress_handler(D,N,X,P) interface causes the callback
3321
** function X to be invoked periodically during long running calls to
3322
** [sqlite3_exec()], [sqlite3_step()] and [sqlite3_get_table()] for
3323
** database connection D.  An example use for this
3324
** interface is to keep a GUI updated during a large query.
3325
**
3326
** ^The parameter P is passed through as the only parameter to the
3327
** callback function X.  ^The parameter N is the approximate number of
3328
** [virtual machine instructions] that are evaluated between successive
3329
** invocations of the callback X.  ^If N is less than one then the progress
3330
** handler is disabled.
3331
**
3332
** ^Only a single progress handler may be defined at one time per
3333
** [database connection]; setting a new progress handler cancels the
3334
** old one.  ^Setting parameter X to NULL disables the progress handler.
3335
** ^The progress handler is also disabled by setting N to a value less
3336
** than 1.
3337
**
3338
** ^If the progress callback returns non-zero, the operation is
3339
** interrupted.  This feature can be used to implement a
3340
** "Cancel" button on a GUI progress dialog box.
3341
**
3342
** The progress handler callback must not do anything that will modify
3343
** the database connection that invoked the progress handler.
3344
** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
3345
** database connections for the meaning of "modify" in this paragraph.
3346
**
3347
*/
3348
SQLITE_API void sqlite3_progress_handler(sqlite3*, int, int(*)(void*), void*);
3349
3350
/*
3351
** CAPI3REF: Opening A New Database Connection
3352
** CONSTRUCTOR: sqlite3
3353
**
3354
** ^These routines open an SQLite database file as specified by the
3355
** filename argument. ^The filename argument is interpreted as UTF-8 for
3356
** sqlite3_open() and sqlite3_open_v2() and as UTF-16 in the native byte
3357
** order for sqlite3_open16(). ^(A [database connection] handle is usually
3358
** returned in *ppDb, even if an error occurs.  The only exception is that
3359
** if SQLite is unable to allocate memory to hold the [sqlite3] object,
3360
** a NULL will be written into *ppDb instead of a pointer to the [sqlite3]
3361
** object.)^ ^(If the database is opened (and/or created) successfully, then
3362
** [SQLITE_OK] is returned.  Otherwise an [error code] is returned.)^ ^The
3363
** [sqlite3_errmsg()] or [sqlite3_errmsg16()] routines can be used to obtain
3364
** an English language description of the error following a failure of any
3365
** of the sqlite3_open() routines.
3366
**
3367
** ^The default encoding will be UTF-8 for databases created using
3368
** sqlite3_open() or sqlite3_open_v2().  ^The default encoding for databases
3369
** created using sqlite3_open16() will be UTF-16 in the native byte order.
3370
**
3371
** Whether or not an error occurs when it is opened, resources
3372
** associated with the [database connection] handle should be released by
3373
** passing it to [sqlite3_close()] when it is no longer required.
3374
**
3375
** The sqlite3_open_v2() interface works like sqlite3_open()
3376
** except that it accepts two additional parameters for additional control
3377
** over the new database connection.  ^(The flags parameter to
3378
** sqlite3_open_v2() must include, at a minimum, one of the following
3379
** three flag combinations:)^
3380
**
3381
** <dl>
3382
** ^(<dt>[SQLITE_OPEN_READONLY]</dt>
3383
** <dd>The database is opened in read-only mode.  If the database does not
3384
** already exist, an error is returned.</dd>)^
3385
**
3386
** ^(<dt>[SQLITE_OPEN_READWRITE]</dt>
3387
** <dd>The database is opened for reading and writing if possible, or reading
3388
** only if the file is write protected by the operating system.  In either
3389
** case the database must already exist, otherwise an error is returned.</dd>)^
3390
**
3391
** ^(<dt>[SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE]</dt>
3392
** <dd>The database is opened for reading and writing, and is created if
3393
** it does not already exist. This is the behavior that is always used for
3394
** sqlite3_open() and sqlite3_open16().</dd>)^
3395
** </dl>
3396
**
3397
** In addition to the required flags, the following optional flags are
3398
** also supported:
3399
**
3400
** <dl>
3401
** ^(<dt>[SQLITE_OPEN_URI]</dt>
3402
** <dd>The filename can be interpreted as a URI if this flag is set.</dd>)^
3403
**
3404
** ^(<dt>[SQLITE_OPEN_MEMORY]</dt>
3405
** <dd>The database will be opened as an in-memory database.  The database
3406
** is named by the "filename" argument for the purposes of cache-sharing,
3407
** if shared cache mode is enabled, but the "filename" is otherwise ignored.
3408
** </dd>)^
3409
**
3410
** ^(<dt>[SQLITE_OPEN_NOMUTEX]</dt>
3411
** <dd>The new database connection will use the "multi-thread"
3412
** [threading mode].)^  This means that separate threads are allowed
3413
** to use SQLite at the same time, as long as each thread is using
3414
** a different [database connection].
3415
**
3416
** ^(<dt>[SQLITE_OPEN_FULLMUTEX]</dt>
3417
** <dd>The new database connection will use the "serialized"
3418
** [threading mode].)^  This means the multiple threads can safely
3419
** attempt to use the same database connection at the same time.
3420
** (Mutexes will block any actual concurrency, but in this mode
3421
** there is no harm in trying.)
3422
**
3423
** ^(<dt>[SQLITE_OPEN_SHAREDCACHE]</dt>
3424
** <dd>The database is opened [shared cache] enabled, overriding
3425
** the default shared cache setting provided by
3426
** [sqlite3_enable_shared_cache()].)^
3427
**
3428
** ^(<dt>[SQLITE_OPEN_PRIVATECACHE]</dt>
3429
** <dd>The database is opened [shared cache] disabled, overriding
3430
** the default shared cache setting provided by
3431
** [sqlite3_enable_shared_cache()].)^
3432
**
3433
** [[OPEN_EXRESCODE]] ^(<dt>[SQLITE_OPEN_EXRESCODE]</dt>
3434
** <dd>The database connection comes up in "extended result code mode".
3435
** In other words, the database behaves has if
3436
** [sqlite3_extended_result_codes(db,1)] where called on the database
3437
** connection as soon as the connection is created. In addition to setting
3438
** the extended result code mode, this flag also causes [sqlite3_open_v2()]
3439
** to return an extended result code.</dd>
3440
**
3441
** [[OPEN_NOFOLLOW]] ^(<dt>[SQLITE_OPEN_NOFOLLOW]</dt>
3442
** <dd>The database filename is not allowed to be a symbolic link</dd>
3443
** </dl>)^
3444
**
3445
** If the 3rd parameter to sqlite3_open_v2() is not one of the
3446
** required combinations shown above optionally combined with other
3447
** [SQLITE_OPEN_READONLY | SQLITE_OPEN_* bits]
3448
** then the behavior is undefined.  Historic versions of SQLite
3449
** have silently ignored surplus bits in the flags parameter to
3450
** sqlite3_open_v2(), however that behavior might not be carried through
3451
** into future versions of SQLite and so applications should not rely
3452
** upon it.  Note in particular that the SQLITE_OPEN_EXCLUSIVE flag is a no-op
3453
** for sqlite3_open_v2().  The SQLITE_OPEN_EXCLUSIVE does *not* cause
3454
** the open to fail if the database already exists.  The SQLITE_OPEN_EXCLUSIVE
3455
** flag is intended for use by the [sqlite3_vfs|VFS interface] only, and not
3456
** by sqlite3_open_v2().
3457
**
3458
** ^The fourth parameter to sqlite3_open_v2() is the name of the
3459
** [sqlite3_vfs] object that defines the operating system interface that
3460
** the new database connection should use.  ^If the fourth parameter is
3461
** a NULL pointer then the default [sqlite3_vfs] object is used.
3462
**
3463
** ^If the filename is ":memory:", then a private, temporary in-memory database
3464
** is created for the connection.  ^This in-memory database will vanish when
3465
** the database connection is closed.  Future versions of SQLite might
3466
** make use of additional special filenames that begin with the ":" character.
3467
** It is recommended that when a database filename actually does begin with
3468
** a ":" character you should prefix the filename with a pathname such as
3469
** "./" to avoid ambiguity.
3470
**
3471
** ^If the filename is an empty string, then a private, temporary
3472
** on-disk database will be created.  ^This private database will be
3473
** automatically deleted as soon as the database connection is closed.
3474
**
3475
** [[URI filenames in sqlite3_open()]] <h3>URI Filenames</h3>
3476
**
3477
** ^If [URI filename] interpretation is enabled, and the filename argument
3478
** begins with "file:", then the filename is interpreted as a URI. ^URI
3479
** filename interpretation is enabled if the [SQLITE_OPEN_URI] flag is
3480
** set in the third argument to sqlite3_open_v2(), or if it has
3481
** been enabled globally using the [SQLITE_CONFIG_URI] option with the
3482
** [sqlite3_config()] method or by the [SQLITE_USE_URI] compile-time option.
3483
** URI filename interpretation is turned off
3484
** by default, but future releases of SQLite might enable URI filename
3485
** interpretation by default.  See "[URI filenames]" for additional
3486
** information.
3487
**
3488
** URI filenames are parsed according to RFC 3986. ^If the URI contains an
3489
** authority, then it must be either an empty string or the string
3490
** "localhost". ^If the authority is not an empty string or "localhost", an
3491
** error is returned to the caller. ^The fragment component of a URI, if
3492
** present, is ignored.
3493
**
3494
** ^SQLite uses the path component of the URI as the name of the disk file
3495
** which contains the database. ^If the path begins with a '/' character,
3496
** then it is interpreted as an absolute path. ^If the path does not begin
3497
** with a '/' (meaning that the authority section is omitted from the URI)
3498
** then the path is interpreted as a relative path.
3499
** ^(On windows, the first component of an absolute path
3500
** is a drive specification (e.g. "C:").)^
3501
**
3502
** [[core URI query parameters]]
3503
** The query component of a URI may contain parameters that are interpreted
3504
** either by SQLite itself, or by a [VFS | custom VFS implementation].
3505
** SQLite and its built-in [VFSes] interpret the
3506
** following query parameters:
3507
**
3508
** <ul>
3509
**   <li> <b>vfs</b>: ^The "vfs" parameter may be used to specify the name of
3510
**     a VFS object that provides the operating system interface that should
3511
**     be used to access the database file on disk. ^If this option is set to
3512
**     an empty string the default VFS object is used. ^Specifying an unknown
3513
**     VFS is an error. ^If sqlite3_open_v2() is used and the vfs option is
3514
**     present, then the VFS specified by the option takes precedence over
3515
**     the value passed as the fourth parameter to sqlite3_open_v2().
3516
**
3517
**   <li> <b>mode</b>: ^(The mode parameter may be set to either "ro", "rw",
3518
**     "rwc", or "memory". Attempting to set it to any other value is
3519
**     an error)^.
3520
**     ^If "ro" is specified, then the database is opened for read-only
3521
**     access, just as if the [SQLITE_OPEN_READONLY] flag had been set in the
3522
**     third argument to sqlite3_open_v2(). ^If the mode option is set to
3523
**     "rw", then the database is opened for read-write (but not create)
3524
**     access, as if SQLITE_OPEN_READWRITE (but not SQLITE_OPEN_CREATE) had
3525
**     been set. ^Value "rwc" is equivalent to setting both
3526
**     SQLITE_OPEN_READWRITE and SQLITE_OPEN_CREATE.  ^If the mode option is
3527
**     set to "memory" then a pure [in-memory database] that never reads
3528
**     or writes from disk is used. ^It is an error to specify a value for
3529
**     the mode parameter that is less restrictive than that specified by
3530
**     the flags passed in the third parameter to sqlite3_open_v2().
3531
**
3532
**   <li> <b>cache</b>: ^The cache parameter may be set to either "shared" or
3533
**     "private". ^Setting it to "shared" is equivalent to setting the
3534
**     SQLITE_OPEN_SHAREDCACHE bit in the flags argument passed to
3535
**     sqlite3_open_v2(). ^Setting the cache parameter to "private" is
3536
**     equivalent to setting the SQLITE_OPEN_PRIVATECACHE bit.
3537
**     ^If sqlite3_open_v2() is used and the "cache" parameter is present in
3538
**     a URI filename, its value overrides any behavior requested by setting
3539
**     SQLITE_OPEN_PRIVATECACHE or SQLITE_OPEN_SHAREDCACHE flag.
3540
**
3541
**  <li> <b>psow</b>: ^The psow parameter indicates whether or not the
3542
**     [powersafe overwrite] property does or does not apply to the
3543
**     storage media on which the database file resides.
3544
**
3545
**  <li> <b>nolock</b>: ^The nolock parameter is a boolean query parameter
3546
**     which if set disables file locking in rollback journal modes.  This
3547
**     is useful for accessing a database on a filesystem that does not
3548
**     support locking.  Caution:  Database corruption might result if two
3549
**     or more processes write to the same database and any one of those
3550
**     processes uses nolock=1.
3551
**
3552
**  <li> <b>immutable</b>: ^The immutable parameter is a boolean query
3553
**     parameter that indicates that the database file is stored on
3554
**     read-only media.  ^When immutable is set, SQLite assumes that the
3555
**     database file cannot be changed, even by a process with higher
3556
**     privilege, and so the database is opened read-only and all locking
3557
**     and change detection is disabled.  Caution: Setting the immutable
3558
**     property on a database file that does in fact change can result
3559
**     in incorrect query results and/or [SQLITE_CORRUPT] errors.
3560
**     See also: [SQLITE_IOCAP_IMMUTABLE].
3561
**
3562
** </ul>
3563
**
3564
** ^Specifying an unknown parameter in the query component of a URI is not an
3565
** error.  Future versions of SQLite might understand additional query
3566
** parameters.  See "[query parameters with special meaning to SQLite]" for
3567
** additional information.
3568
**
3569
** [[URI filename examples]] <h3>URI filename examples</h3>
3570
**
3571
** <table border="1" align=center cellpadding=5>
3572
** <tr><th> URI filenames <th> Results
3573
** <tr><td> file:data.db <td>
3574
**          Open the file "data.db" in the current directory.
3575
** <tr><td> file:/home/fred/data.db<br>
3576
**          file:///home/fred/data.db <br>
3577
**          file://localhost/home/fred/data.db <br> <td>
3578
**          Open the database file "/home/fred/data.db".
3579
** <tr><td> file://darkstar/home/fred/data.db <td>
3580
**          An error. "darkstar" is not a recognized authority.
3581
** <tr><td style="white-space:nowrap">
3582
**          file:///C:/Documents%20and%20Settings/fred/Desktop/data.db
3583
**     <td> Windows only: Open the file "data.db" on fred's desktop on drive
3584
**          C:. Note that the %20 escaping in this example is not strictly
3585
**          necessary - space characters can be used literally
3586
**          in URI filenames.
3587
** <tr><td> file:data.db?mode=ro&cache=private <td>
3588
**          Open file "data.db" in the current directory for read-only access.
3589
**          Regardless of whether or not shared-cache mode is enabled by
3590
**          default, use a private cache.
3591
** <tr><td> file:/home/fred/data.db?vfs=unix-dotfile <td>
3592
**          Open file "/home/fred/data.db". Use the special VFS "unix-dotfile"
3593
**          that uses dot-files in place of posix advisory locking.
3594
** <tr><td> file:data.db?mode=readonly <td>
3595
**          An error. "readonly" is not a valid option for the "mode" parameter.
3596
**          Use "ro" instead:  "file:data.db?mode=ro".
3597
** </table>
3598
**
3599
** ^URI hexadecimal escape sequences (%HH) are supported within the path and
3600
** query components of a URI. A hexadecimal escape sequence consists of a
3601
** percent sign - "%" - followed by exactly two hexadecimal digits
3602
** specifying an octet value. ^Before the path or query components of a
3603
** URI filename are interpreted, they are encoded using UTF-8 and all
3604
** hexadecimal escape sequences replaced by a single byte containing the
3605
** corresponding octet. If this process generates an invalid UTF-8 encoding,
3606
** the results are undefined.
3607
**
3608
** <b>Note to Windows users:</b>  The encoding used for the filename argument
3609
** of sqlite3_open() and sqlite3_open_v2() must be UTF-8, not whatever
3610
** codepage is currently defined.  Filenames containing international
3611
** characters must be converted to UTF-8 prior to passing them into
3612
** sqlite3_open() or sqlite3_open_v2().
3613
**
3614
** <b>Note to Windows Runtime users:</b>  The temporary directory must be set
3615
** prior to calling sqlite3_open() or sqlite3_open_v2().  Otherwise, various
3616
** features that require the use of temporary files may fail.
3617
**
3618
** See also: [sqlite3_temp_directory]
3619
*/
3620
SQLITE_API int sqlite3_open(
3621
  const char *filename,   /* Database filename (UTF-8) */
3622
  sqlite3 **ppDb          /* OUT: SQLite db handle */
3623
);
3624
SQLITE_API int sqlite3_open16(
3625
  const void *filename,   /* Database filename (UTF-16) */
3626
  sqlite3 **ppDb          /* OUT: SQLite db handle */
3627
);
3628
SQLITE_API int sqlite3_open_v2(
3629
  const char *filename,   /* Database filename (UTF-8) */
3630
  sqlite3 **ppDb,         /* OUT: SQLite db handle */
3631
  int flags,              /* Flags */
3632
  const char *zVfs        /* Name of VFS module to use */
3633
);
3634
3635
/*
3636
** CAPI3REF: Obtain Values For URI Parameters
3637
**
3638
** These are utility routines, useful to [VFS|custom VFS implementations],
3639
** that check if a database file was a URI that contained a specific query
3640
** parameter, and if so obtains the value of that query parameter.
3641
**
3642
** The first parameter to these interfaces (hereafter referred to
3643
** as F) must be one of:
3644
** <ul>
3645
** <li> A database filename pointer created by the SQLite core and
3646
** passed into the xOpen() method of a VFS implemention, or
3647
** <li> A filename obtained from [sqlite3_db_filename()], or
3648
** <li> A new filename constructed using [sqlite3_create_filename()].
3649
** </ul>
3650
** If the F parameter is not one of the above, then the behavior is
3651
** undefined and probably undesirable.  Older versions of SQLite were
3652
** more tolerant of invalid F parameters than newer versions.
3653
**
3654
** If F is a suitable filename (as described in the previous paragraph)
3655
** and if P is the name of the query parameter, then
3656
** sqlite3_uri_parameter(F,P) returns the value of the P
3657
** parameter if it exists or a NULL pointer if P does not appear as a
3658
** query parameter on F.  If P is a query parameter of F and it
3659
** has no explicit value, then sqlite3_uri_parameter(F,P) returns
3660
** a pointer to an empty string.
3661
**
3662
** The sqlite3_uri_boolean(F,P,B) routine assumes that P is a boolean
3663
** parameter and returns true (1) or false (0) according to the value
3664
** of P.  The sqlite3_uri_boolean(F,P,B) routine returns true (1) if the
3665
** value of query parameter P is one of "yes", "true", or "on" in any
3666
** case or if the value begins with a non-zero number.  The
3667
** sqlite3_uri_boolean(F,P,B) routines returns false (0) if the value of
3668
** query parameter P is one of "no", "false", or "off" in any case or
3669
** if the value begins with a numeric zero.  If P is not a query
3670
** parameter on F or if the value of P does not match any of the
3671
** above, then sqlite3_uri_boolean(F,P,B) returns (B!=0).
3672
**
3673
** The sqlite3_uri_int64(F,P,D) routine converts the value of P into a
3674
** 64-bit signed integer and returns that integer, or D if P does not
3675
** exist.  If the value of P is something other than an integer, then
3676
** zero is returned.
3677
**
3678
** The sqlite3_uri_key(F,N) returns a pointer to the name (not
3679
** the value) of the N-th query parameter for filename F, or a NULL
3680
** pointer if N is less than zero or greater than the number of query
3681
** parameters minus 1.  The N value is zero-based so N should be 0 to obtain
3682
** the name of the first query parameter, 1 for the second parameter, and
3683
** so forth.
3684
**
3685
** If F is a NULL pointer, then sqlite3_uri_parameter(F,P) returns NULL and
3686
** sqlite3_uri_boolean(F,P,B) returns B.  If F is not a NULL pointer and
3687
** is not a database file pathname pointer that the SQLite core passed
3688
** into the xOpen VFS method, then the behavior of this routine is undefined
3689
** and probably undesirable.
3690
**
3691
** Beginning with SQLite [version 3.31.0] ([dateof:3.31.0]) the input F
3692
** parameter can also be the name of a rollback journal file or WAL file
3693
** in addition to the main database file.  Prior to version 3.31.0, these
3694
** routines would only work if F was the name of the main database file.
3695
** When the F parameter is the name of the rollback journal or WAL file,
3696
** it has access to all the same query parameters as were found on the
3697
** main database file.
3698
**
3699
** See the [URI filename] documentation for additional information.
3700
*/
3701
SQLITE_API const char *sqlite3_uri_parameter(const char *zFilename, const char *zParam);
3702
SQLITE_API int sqlite3_uri_boolean(const char *zFile, const char *zParam, int bDefault);
3703
SQLITE_API sqlite3_int64 sqlite3_uri_int64(const char*, const char*, sqlite3_int64);
3704
SQLITE_API const char *sqlite3_uri_key(const char *zFilename, int N);
3705
3706
/*
3707
** CAPI3REF:  Translate filenames
3708
**
3709
** These routines are available to [VFS|custom VFS implementations] for
3710
** translating filenames between the main database file, the journal file,
3711
** and the WAL file.
3712
**
3713
** If F is the name of an sqlite database file, journal file, or WAL file
3714
** passed by the SQLite core into the VFS, then sqlite3_filename_database(F)
3715
** returns the name of the corresponding database file.
3716
**
3717
** If F is the name of an sqlite database file, journal file, or WAL file
3718
** passed by the SQLite core into the VFS, or if F is a database filename
3719
** obtained from [sqlite3_db_filename()], then sqlite3_filename_journal(F)
3720
** returns the name of the corresponding rollback journal file.
3721
**
3722
** If F is the name of an sqlite database file, journal file, or WAL file
3723
** that was passed by the SQLite core into the VFS, or if F is a database
3724
** filename obtained from [sqlite3_db_filename()], then
3725
** sqlite3_filename_wal(F) returns the name of the corresponding
3726
** WAL file.
3727
**
3728
** In all of the above, if F is not the name of a database, journal or WAL
3729
** filename passed into the VFS from the SQLite core and F is not the
3730
** return value from [sqlite3_db_filename()], then the result is
3731
** undefined and is likely a memory access violation.
3732
*/
3733
SQLITE_API const char *sqlite3_filename_database(const char*);
3734
SQLITE_API const char *sqlite3_filename_journal(const char*);
3735
SQLITE_API const char *sqlite3_filename_wal(const char*);
3736
3737
/*
3738
** CAPI3REF:  Database File Corresponding To A Journal
3739
**
3740
** ^If X is the name of a rollback or WAL-mode journal file that is
3741
** passed into the xOpen method of [sqlite3_vfs], then
3742
** sqlite3_database_file_object(X) returns a pointer to the [sqlite3_file]
3743
** object that represents the main database file.
3744
**
3745
** This routine is intended for use in custom [VFS] implementations
3746
** only.  It is not a general-purpose interface.
3747
** The argument sqlite3_file_object(X) must be a filename pointer that
3748
** has been passed into [sqlite3_vfs].xOpen method where the
3749
** flags parameter to xOpen contains one of the bits
3750
** [SQLITE_OPEN_MAIN_JOURNAL] or [SQLITE_OPEN_WAL].  Any other use
3751
** of this routine results in undefined and probably undesirable
3752
** behavior.
3753
*/
3754
SQLITE_API sqlite3_file *sqlite3_database_file_object(const char*);
3755
3756
/*
3757
** CAPI3REF: Create and Destroy VFS Filenames
3758
**
3759
** These interfces are provided for use by [VFS shim] implementations and
3760
** are not useful outside of that context.
3761
**
3762
** The sqlite3_create_filename(D,J,W,N,P) allocates memory to hold a version of
3763
** database filename D with corresponding journal file J and WAL file W and
3764
** with N URI parameters key/values pairs in the array P.  The result from
3765
** sqlite3_create_filename(D,J,W,N,P) is a pointer to a database filename that
3766
** is safe to pass to routines like:
3767
** <ul>
3768
** <li> [sqlite3_uri_parameter()],
3769
** <li> [sqlite3_uri_boolean()],
3770
** <li> [sqlite3_uri_int64()],
3771
** <li> [sqlite3_uri_key()],
3772
** <li> [sqlite3_filename_database()],
3773
** <li> [sqlite3_filename_journal()], or
3774
** <li> [sqlite3_filename_wal()].
3775
** </ul>
3776
** If a memory allocation error occurs, sqlite3_create_filename() might
3777
** return a NULL pointer.  The memory obtained from sqlite3_create_filename(X)
3778
** must be released by a corresponding call to sqlite3_free_filename(Y).
3779
**
3780
** The P parameter in sqlite3_create_filename(D,J,W,N,P) should be an array
3781
** of 2*N pointers to strings.  Each pair of pointers in this array corresponds
3782
** to a key and value for a query parameter.  The P parameter may be a NULL
3783
** pointer if N is zero.  None of the 2*N pointers in the P array may be
3784
** NULL pointers and key pointers should not be empty strings.
3785
** None of the D, J, or W parameters to sqlite3_create_filename(D,J,W,N,P) may
3786
** be NULL pointers, though they can be empty strings.
3787
**
3788
** The sqlite3_free_filename(Y) routine releases a memory allocation
3789
** previously obtained from sqlite3_create_filename().  Invoking
3790
** sqlite3_free_filename(Y) where Y is a NULL pointer is a harmless no-op.
3791
**
3792
** If the Y parameter to sqlite3_free_filename(Y) is anything other
3793
** than a NULL pointer or a pointer previously acquired from
3794
** sqlite3_create_filename(), then bad things such as heap
3795
** corruption or segfaults may occur. The value Y should not be
3796
** used again after sqlite3_free_filename(Y) has been called.  This means
3797
** that if the [sqlite3_vfs.xOpen()] method of a VFS has been called using Y,
3798
** then the corresponding [sqlite3_module.xClose() method should also be
3799
** invoked prior to calling sqlite3_free_filename(Y).
3800
*/
3801
SQLITE_API char *sqlite3_create_filename(
3802
  const char *zDatabase,
3803
  const char *zJournal,
3804
  const char *zWal,
3805
  int nParam,
3806
  const char **azParam
3807
);
3808
SQLITE_API void sqlite3_free_filename(char*);
3809
3810
/*
3811
** CAPI3REF: Error Codes And Messages
3812
** METHOD: sqlite3
3813
**
3814
** ^If the most recent sqlite3_* API call associated with
3815
** [database connection] D failed, then the sqlite3_errcode(D) interface
3816
** returns the numeric [result code] or [extended result code] for that
3817
** API call.
3818
** ^The sqlite3_extended_errcode()
3819
** interface is the same except that it always returns the
3820
** [extended result code] even when extended result codes are
3821
** disabled.
3822
**
3823
** The values returned by sqlite3_errcode() and/or
3824
** sqlite3_extended_errcode() might change with each API call.
3825
** Except, there are some interfaces that are guaranteed to never
3826
** change the value of the error code.  The error-code preserving
3827
** interfaces include the following:
3828
**
3829
** <ul>
3830
** <li> sqlite3_errcode()
3831
** <li> sqlite3_extended_errcode()
3832
** <li> sqlite3_errmsg()
3833
** <li> sqlite3_errmsg16()
3834
** <li> sqlite3_error_offset()
3835
** </ul>
3836
**
3837
** ^The sqlite3_errmsg() and sqlite3_errmsg16() return English-language
3838
** text that describes the error, as either UTF-8 or UTF-16 respectively.
3839
** ^(Memory to hold the error message string is managed internally.
3840
** The application does not need to worry about freeing the result.
3841
** However, the error string might be overwritten or deallocated by
3842
** subsequent calls to other SQLite interface functions.)^
3843
**
3844
** ^The sqlite3_errstr() interface returns the English-language text
3845
** that describes the [result code], as UTF-8.
3846
** ^(Memory to hold the error message string is managed internally
3847
** and must not be freed by the application)^.
3848
**
3849
** ^If the most recent error references a specific token in the input
3850
** SQL, the sqlite3_error_offset() interface returns the byte offset
3851
** of the start of that token.  ^The byte offset returned by
3852
** sqlite3_error_offset() assumes that the input SQL is UTF8.
3853
** ^If the most recent error does not reference a specific token in the input
3854
** SQL, then the sqlite3_error_offset() function returns -1.
3855
**
3856
** When the serialized [threading mode] is in use, it might be the
3857
** case that a second error occurs on a separate thread in between
3858
** the time of the first error and the call to these interfaces.
3859
** When that happens, the second error will be reported since these
3860
** interfaces always report the most recent result.  To avoid
3861
** this, each thread can obtain exclusive use of the [database connection] D
3862
** by invoking [sqlite3_mutex_enter]([sqlite3_db_mutex](D)) before beginning
3863
** to use D and invoking [sqlite3_mutex_leave]([sqlite3_db_mutex](D)) after
3864
** all calls to the interfaces listed here are completed.
3865
**
3866
** If an interface fails with SQLITE_MISUSE, that means the interface
3867
** was invoked incorrectly by the application.  In that case, the
3868
** error code and message may or may not be set.
3869
*/
3870
SQLITE_API int sqlite3_errcode(sqlite3 *db);
3871
SQLITE_API int sqlite3_extended_errcode(sqlite3 *db);
3872
SQLITE_API const char *sqlite3_errmsg(sqlite3*);
3873
SQLITE_API const void *sqlite3_errmsg16(sqlite3*);
3874
SQLITE_API const char *sqlite3_errstr(int);
3875
SQLITE_API int sqlite3_error_offset(sqlite3 *db);
3876
3877
/*
3878
** CAPI3REF: Prepared Statement Object
3879
** KEYWORDS: {prepared statement} {prepared statements}
3880
**
3881
** An instance of this object represents a single SQL statement that
3882
** has been compiled into binary form and is ready to be evaluated.
3883
**
3884
** Think of each SQL statement as a separate computer program.  The
3885
** original SQL text is source code.  A prepared statement object
3886
** is the compiled object code.  All SQL must be converted into a
3887
** prepared statement before it can be run.
3888
**
3889
** The life-cycle of a prepared statement object usually goes like this:
3890
**
3891
** <ol>
3892
** <li> Create the prepared statement object using [sqlite3_prepare_v2()].
3893
** <li> Bind values to [parameters] using the sqlite3_bind_*()
3894
**      interfaces.
3895
** <li> Run the SQL by calling [sqlite3_step()] one or more times.
3896
** <li> Reset the prepared statement using [sqlite3_reset()] then go back
3897
**      to step 2.  Do this zero or more times.
3898
** <li> Destroy the object using [sqlite3_finalize()].
3899
** </ol>
3900
*/
3901
typedef struct sqlite3_stmt sqlite3_stmt;
3902
3903
/*
3904
** CAPI3REF: Run-time Limits
3905
** METHOD: sqlite3
3906
**
3907
** ^(This interface allows the size of various constructs to be limited
3908
** on a connection by connection basis.  The first parameter is the
3909
** [database connection] whose limit is to be set or queried.  The
3910
** second parameter is one of the [limit categories] that define a
3911
** class of constructs to be size limited.  The third parameter is the
3912
** new limit for that construct.)^
3913
**
3914
** ^If the new limit is a negative number, the limit is unchanged.
3915
** ^(For each limit category SQLITE_LIMIT_<i>NAME</i> there is a
3916
** [limits | hard upper bound]
3917
** set at compile-time by a C preprocessor macro called
3918
** [limits | SQLITE_MAX_<i>NAME</i>].
3919
** (The "_LIMIT_" in the name is changed to "_MAX_".))^
3920
** ^Attempts to increase a limit above its hard upper bound are
3921
** silently truncated to the hard upper bound.
3922
**
3923
** ^Regardless of whether or not the limit was changed, the
3924
** [sqlite3_limit()] interface returns the prior value of the limit.
3925
** ^Hence, to find the current value of a limit without changing it,
3926
** simply invoke this interface with the third parameter set to -1.
3927
**
3928
** Run-time limits are intended for use in applications that manage
3929
** both their own internal database and also databases that are controlled
3930
** by untrusted external sources.  An example application might be a
3931
** web browser that has its own databases for storing history and
3932
** separate databases controlled by JavaScript applications downloaded
3933
** off the Internet.  The internal databases can be given the
3934
** large, default limits.  Databases managed by external sources can
3935
** be given much smaller limits designed to prevent a denial of service
3936
** attack.  Developers might also want to use the [sqlite3_set_authorizer()]
3937
** interface to further control untrusted SQL.  The size of the database
3938
** created by an untrusted script can be contained using the
3939
** [max_page_count] [PRAGMA].
3940
**
3941
** New run-time limit categories may be added in future releases.
3942
*/
3943
SQLITE_API int sqlite3_limit(sqlite3*, int id, int newVal);
3944
3945
/*
3946
** CAPI3REF: Run-Time Limit Categories
3947
** KEYWORDS: {limit category} {*limit categories}
3948
**
3949
** These constants define various performance limits
3950
** that can be lowered at run-time using [sqlite3_limit()].
3951
** The synopsis of the meanings of the various limits is shown below.
3952
** Additional information is available at [limits | Limits in SQLite].
3953
**
3954
** <dl>
3955
** [[SQLITE_LIMIT_LENGTH]] ^(<dt>SQLITE_LIMIT_LENGTH</dt>
3956
** <dd>The maximum size of any string or BLOB or table row, in bytes.<dd>)^
3957
**
3958
** [[SQLITE_LIMIT_SQL_LENGTH]] ^(<dt>SQLITE_LIMIT_SQL_LENGTH</dt>
3959
** <dd>The maximum length of an SQL statement, in bytes.</dd>)^
3960
**
3961
** [[SQLITE_LIMIT_COLUMN]] ^(<dt>SQLITE_LIMIT_COLUMN</dt>
3962
** <dd>The maximum number of columns in a table definition or in the
3963
** result set of a [SELECT] or the maximum number of columns in an index
3964
** or in an ORDER BY or GROUP BY clause.</dd>)^
3965
**
3966
** [[SQLITE_LIMIT_EXPR_DEPTH]] ^(<dt>SQLITE_LIMIT_EXPR_DEPTH</dt>
3967
** <dd>The maximum depth of the parse tree on any expression.</dd>)^
3968
**
3969
** [[SQLITE_LIMIT_COMPOUND_SELECT]] ^(<dt>SQLITE_LIMIT_COMPOUND_SELECT</dt>
3970
** <dd>The maximum number of terms in a compound SELECT statement.</dd>)^
3971
**
3972
** [[SQLITE_LIMIT_VDBE_OP]] ^(<dt>SQLITE_LIMIT_VDBE_OP</dt>
3973
** <dd>The maximum number of instructions in a virtual machine program
3974
** used to implement an SQL statement.  If [sqlite3_prepare_v2()] or
3975
** the equivalent tries to allocate space for more than this many opcodes
3976
** in a single prepared statement, an SQLITE_NOMEM error is returned.</dd>)^
3977
**
3978
** [[SQLITE_LIMIT_FUNCTION_ARG]] ^(<dt>SQLITE_LIMIT_FUNCTION_ARG</dt>
3979
** <dd>The maximum number of arguments on a function.</dd>)^
3980
**
3981
** [[SQLITE_LIMIT_ATTACHED]] ^(<dt>SQLITE_LIMIT_ATTACHED</dt>
3982
** <dd>The maximum number of [ATTACH | attached databases].)^</dd>
3983
**
3984
** [[SQLITE_LIMIT_LIKE_PATTERN_LENGTH]]
3985
** ^(<dt>SQLITE_LIMIT_LIKE_PATTERN_LENGTH</dt>
3986
** <dd>The maximum length of the pattern argument to the [LIKE] or
3987
** [GLOB] operators.</dd>)^
3988
**
3989
** [[SQLITE_LIMIT_VARIABLE_NUMBER]]
3990
** ^(<dt>SQLITE_LIMIT_VARIABLE_NUMBER</dt>
3991
** <dd>The maximum index number of any [parameter] in an SQL statement.)^
3992
**
3993
** [[SQLITE_LIMIT_TRIGGER_DEPTH]] ^(<dt>SQLITE_LIMIT_TRIGGER_DEPTH</dt>
3994
** <dd>The maximum depth of recursion for triggers.</dd>)^
3995
**
3996
** [[SQLITE_LIMIT_WORKER_THREADS]] ^(<dt>SQLITE_LIMIT_WORKER_THREADS</dt>
3997
** <dd>The maximum number of auxiliary worker threads that a single
3998
** [prepared statement] may start.</dd>)^
3999
** </dl>
4000
*/
4001
#define SQLITE_LIMIT_LENGTH                    0
4002
1.59k
#define SQLITE_LIMIT_SQL_LENGTH                1
4003
#define SQLITE_LIMIT_COLUMN                    2
4004
#define SQLITE_LIMIT_EXPR_DEPTH                3
4005
#define SQLITE_LIMIT_COMPOUND_SELECT           4
4006
#define SQLITE_LIMIT_VDBE_OP                   5
4007
#define SQLITE_LIMIT_FUNCTION_ARG              6
4008
#define SQLITE_LIMIT_ATTACHED                  7
4009
#define SQLITE_LIMIT_LIKE_PATTERN_LENGTH       8
4010
#define SQLITE_LIMIT_VARIABLE_NUMBER           9
4011
#define SQLITE_LIMIT_TRIGGER_DEPTH            10
4012
#define SQLITE_LIMIT_WORKER_THREADS           11
4013
4014
/*
4015
** CAPI3REF: Prepare Flags
4016
**
4017
** These constants define various flags that can be passed into
4018
** "prepFlags" parameter of the [sqlite3_prepare_v3()] and
4019
** [sqlite3_prepare16_v3()] interfaces.
4020
**
4021
** New flags may be added in future releases of SQLite.
4022
**
4023
** <dl>
4024
** [[SQLITE_PREPARE_PERSISTENT]] ^(<dt>SQLITE_PREPARE_PERSISTENT</dt>
4025
** <dd>The SQLITE_PREPARE_PERSISTENT flag is a hint to the query planner
4026
** that the prepared statement will be retained for a long time and
4027
** probably reused many times.)^ ^Without this flag, [sqlite3_prepare_v3()]
4028
** and [sqlite3_prepare16_v3()] assume that the prepared statement will
4029
** be used just once or at most a few times and then destroyed using
4030
** [sqlite3_finalize()] relatively soon. The current implementation acts
4031
** on this hint by avoiding the use of [lookaside memory] so as not to
4032
** deplete the limited store of lookaside memory. Future versions of
4033
** SQLite may act on this hint differently.
4034
**
4035
** [[SQLITE_PREPARE_NORMALIZE]] <dt>SQLITE_PREPARE_NORMALIZE</dt>
4036
** <dd>The SQLITE_PREPARE_NORMALIZE flag is a no-op. This flag used
4037
** to be required for any prepared statement that wanted to use the
4038
** [sqlite3_normalized_sql()] interface.  However, the
4039
** [sqlite3_normalized_sql()] interface is now available to all
4040
** prepared statements, regardless of whether or not they use this
4041
** flag.
4042
**
4043
** [[SQLITE_PREPARE_NO_VTAB]] <dt>SQLITE_PREPARE_NO_VTAB</dt>
4044
** <dd>The SQLITE_PREPARE_NO_VTAB flag causes the SQL compiler
4045
** to return an error (error code SQLITE_ERROR) if the statement uses
4046
** any virtual tables.
4047
** </dl>
4048
*/
4049
#define SQLITE_PREPARE_PERSISTENT              0x01
4050
#define SQLITE_PREPARE_NORMALIZE               0x02
4051
#define SQLITE_PREPARE_NO_VTAB                 0x04
4052
4053
/*
4054
** CAPI3REF: Compiling An SQL Statement
4055
** KEYWORDS: {SQL statement compiler}
4056
** METHOD: sqlite3
4057
** CONSTRUCTOR: sqlite3_stmt
4058
**
4059
** To execute an SQL statement, it must first be compiled into a byte-code
4060
** program using one of these routines.  Or, in other words, these routines
4061
** are constructors for the [prepared statement] object.
4062
**
4063
** The preferred routine to use is [sqlite3_prepare_v2()].  The
4064
** [sqlite3_prepare()] interface is legacy and should be avoided.
4065
** [sqlite3_prepare_v3()] has an extra "prepFlags" option that is used
4066
** for special purposes.
4067
**
4068
** The use of the UTF-8 interfaces is preferred, as SQLite currently
4069
** does all parsing using UTF-8.  The UTF-16 interfaces are provided
4070
** as a convenience.  The UTF-16 interfaces work by converting the
4071
** input text into UTF-8, then invoking the corresponding UTF-8 interface.
4072
**
4073
** The first argument, "db", is a [database connection] obtained from a
4074
** prior successful call to [sqlite3_open()], [sqlite3_open_v2()] or
4075
** [sqlite3_open16()].  The database connection must not have been closed.
4076
**
4077
** The second argument, "zSql", is the statement to be compiled, encoded
4078
** as either UTF-8 or UTF-16.  The sqlite3_prepare(), sqlite3_prepare_v2(),
4079
** and sqlite3_prepare_v3()
4080
** interfaces use UTF-8, and sqlite3_prepare16(), sqlite3_prepare16_v2(),
4081
** and sqlite3_prepare16_v3() use UTF-16.
4082
**
4083
** ^If the nByte argument is negative, then zSql is read up to the
4084
** first zero terminator. ^If nByte is positive, then it is the
4085
** number of bytes read from zSql.  ^If nByte is zero, then no prepared
4086
** statement is generated.
4087
** If the caller knows that the supplied string is nul-terminated, then
4088
** there is a small performance advantage to passing an nByte parameter that
4089
** is the number of bytes in the input string <i>including</i>
4090
** the nul-terminator.
4091
**
4092
** ^If pzTail is not NULL then *pzTail is made to point to the first byte
4093
** past the end of the first SQL statement in zSql.  These routines only
4094
** compile the first statement in zSql, so *pzTail is left pointing to
4095
** what remains uncompiled.
4096
**
4097
** ^*ppStmt is left pointing to a compiled [prepared statement] that can be
4098
** executed using [sqlite3_step()].  ^If there is an error, *ppStmt is set
4099
** to NULL.  ^If the input text contains no SQL (if the input is an empty
4100
** string or a comment) then *ppStmt is set to NULL.
4101
** The calling procedure is responsible for deleting the compiled
4102
** SQL statement using [sqlite3_finalize()] after it has finished with it.
4103
** ppStmt may not be NULL.
4104
**
4105
** ^On success, the sqlite3_prepare() family of routines return [SQLITE_OK];
4106
** otherwise an [error code] is returned.
4107
**
4108
** The sqlite3_prepare_v2(), sqlite3_prepare_v3(), sqlite3_prepare16_v2(),
4109
** and sqlite3_prepare16_v3() interfaces are recommended for all new programs.
4110
** The older interfaces (sqlite3_prepare() and sqlite3_prepare16())
4111
** are retained for backwards compatibility, but their use is discouraged.
4112
** ^In the "vX" interfaces, the prepared statement
4113
** that is returned (the [sqlite3_stmt] object) contains a copy of the
4114
** original SQL text. This causes the [sqlite3_step()] interface to
4115
** behave differently in three ways:
4116
**
4117
** <ol>
4118
** <li>
4119
** ^If the database schema changes, instead of returning [SQLITE_SCHEMA] as it
4120
** always used to do, [sqlite3_step()] will automatically recompile the SQL
4121
** statement and try to run it again. As many as [SQLITE_MAX_SCHEMA_RETRY]
4122
** retries will occur before sqlite3_step() gives up and returns an error.
4123
** </li>
4124
**
4125
** <li>
4126
** ^When an error occurs, [sqlite3_step()] will return one of the detailed
4127
** [error codes] or [extended error codes].  ^The legacy behavior was that
4128
** [sqlite3_step()] would only return a generic [SQLITE_ERROR] result code
4129
** and the application would have to make a second call to [sqlite3_reset()]
4130
** in order to find the underlying cause of the problem. With the "v2" prepare
4131
** interfaces, the underlying reason for the error is returned immediately.
4132
** </li>
4133
**
4134
** <li>
4135
** ^If the specific value bound to a [parameter | host parameter] in the
4136
** WHERE clause might influence the choice of query plan for a statement,
4137
** then the statement will be automatically recompiled, as if there had been
4138
** a schema change, on the first [sqlite3_step()] call following any change
4139
** to the [sqlite3_bind_text | bindings] of that [parameter].
4140
** ^The specific value of a WHERE-clause [parameter] might influence the
4141
** choice of query plan if the parameter is the left-hand side of a [LIKE]
4142
** or [GLOB] operator or if the parameter is compared to an indexed column
4143
** and the [SQLITE_ENABLE_STAT4] compile-time option is enabled.
4144
** </li>
4145
** </ol>
4146
**
4147
** <p>^sqlite3_prepare_v3() differs from sqlite3_prepare_v2() only in having
4148
** the extra prepFlags parameter, which is a bit array consisting of zero or
4149
** more of the [SQLITE_PREPARE_PERSISTENT|SQLITE_PREPARE_*] flags.  ^The
4150
** sqlite3_prepare_v2() interface works exactly the same as
4151
** sqlite3_prepare_v3() with a zero prepFlags parameter.
4152
*/
4153
SQLITE_API int sqlite3_prepare(
4154
  sqlite3 *db,            /* Database handle */
4155
  const char *zSql,       /* SQL statement, UTF-8 encoded */
4156
  int nByte,              /* Maximum length of zSql in bytes. */
4157
  sqlite3_stmt **ppStmt,  /* OUT: Statement handle */
4158
  const char **pzTail     /* OUT: Pointer to unused portion of zSql */
4159
);
4160
SQLITE_API int sqlite3_prepare_v2(
4161
  sqlite3 *db,            /* Database handle */
4162
  const char *zSql,       /* SQL statement, UTF-8 encoded */
4163
  int nByte,              /* Maximum length of zSql in bytes. */
4164
  sqlite3_stmt **ppStmt,  /* OUT: Statement handle */
4165
  const char **pzTail     /* OUT: Pointer to unused portion of zSql */
4166
);
4167
SQLITE_API int sqlite3_prepare_v3(
4168
  sqlite3 *db,            /* Database handle */
4169
  const char *zSql,       /* SQL statement, UTF-8 encoded */
4170
  int nByte,              /* Maximum length of zSql in bytes. */
4171
  unsigned int prepFlags, /* Zero or more SQLITE_PREPARE_ flags */
4172
  sqlite3_stmt **ppStmt,  /* OUT: Statement handle */
4173
  const char **pzTail     /* OUT: Pointer to unused portion of zSql */
4174
);
4175
SQLITE_API int sqlite3_prepare16(
4176
  sqlite3 *db,            /* Database handle */
4177
  const void *zSql,       /* SQL statement, UTF-16 encoded */
4178
  int nByte,              /* Maximum length of zSql in bytes. */
4179
  sqlite3_stmt **ppStmt,  /* OUT: Statement handle */
4180
  const void **pzTail     /* OUT: Pointer to unused portion of zSql */
4181
);
4182
SQLITE_API int sqlite3_prepare16_v2(
4183
  sqlite3 *db,            /* Database handle */
4184
  const void *zSql,       /* SQL statement, UTF-16 encoded */
4185
  int nByte,              /* Maximum length of zSql in bytes. */
4186
  sqlite3_stmt **ppStmt,  /* OUT: Statement handle */
4187
  const void **pzTail     /* OUT: Pointer to unused portion of zSql */
4188
);
4189
SQLITE_API int sqlite3_prepare16_v3(
4190
  sqlite3 *db,            /* Database handle */
4191
  const void *zSql,       /* SQL statement, UTF-16 encoded */
4192
  int nByte,              /* Maximum length of zSql in bytes. */
4193
  unsigned int prepFlags, /* Zero or more SQLITE_PREPARE_ flags */
4194
  sqlite3_stmt **ppStmt,  /* OUT: Statement handle */
4195
  const void **pzTail     /* OUT: Pointer to unused portion of zSql */
4196
);
4197
4198
/*
4199
** CAPI3REF: Retrieving Statement SQL
4200
** METHOD: sqlite3_stmt
4201
**
4202
** ^The sqlite3_sql(P) interface returns a pointer to a copy of the UTF-8
4203
** SQL text used to create [prepared statement] P if P was
4204
** created by [sqlite3_prepare_v2()], [sqlite3_prepare_v3()],
4205
** [sqlite3_prepare16_v2()], or [sqlite3_prepare16_v3()].
4206
** ^The sqlite3_expanded_sql(P) interface returns a pointer to a UTF-8
4207
** string containing the SQL text of prepared statement P with
4208
** [bound parameters] expanded.
4209
** ^The sqlite3_normalized_sql(P) interface returns a pointer to a UTF-8
4210
** string containing the normalized SQL text of prepared statement P.  The
4211
** semantics used to normalize a SQL statement are unspecified and subject
4212
** to change.  At a minimum, literal values will be replaced with suitable
4213
** placeholders.
4214
**
4215
** ^(For example, if a prepared statement is created using the SQL
4216
** text "SELECT $abc,:xyz" and if parameter $abc is bound to integer 2345
4217
** and parameter :xyz is unbound, then sqlite3_sql() will return
4218
** the original string, "SELECT $abc,:xyz" but sqlite3_expanded_sql()
4219
** will return "SELECT 2345,NULL".)^
4220
**
4221
** ^The sqlite3_expanded_sql() interface returns NULL if insufficient memory
4222
** is available to hold the result, or if the result would exceed the
4223
** the maximum string length determined by the [SQLITE_LIMIT_LENGTH].
4224
**
4225
** ^The [SQLITE_TRACE_SIZE_LIMIT] compile-time option limits the size of
4226
** bound parameter expansions.  ^The [SQLITE_OMIT_TRACE] compile-time
4227
** option causes sqlite3_expanded_sql() to always return NULL.
4228
**
4229
** ^The strings returned by sqlite3_sql(P) and sqlite3_normalized_sql(P)
4230
** are managed by SQLite and are automatically freed when the prepared
4231
** statement is finalized.
4232
** ^The string returned by sqlite3_expanded_sql(P), on the other hand,
4233
** is obtained from [sqlite3_malloc()] and must be freed by the application
4234
** by passing it to [sqlite3_free()].
4235
**
4236
** ^The sqlite3_normalized_sql() interface is only available if
4237
** the [SQLITE_ENABLE_NORMALIZE] compile-time option is defined.
4238
*/
4239
SQLITE_API const char *sqlite3_sql(sqlite3_stmt *pStmt);
4240
SQLITE_API char *sqlite3_expanded_sql(sqlite3_stmt *pStmt);
4241
#ifdef SQLITE_ENABLE_NORMALIZE
4242
SQLITE_API const char *sqlite3_normalized_sql(sqlite3_stmt *pStmt);
4243
#endif
4244
4245
/*
4246
** CAPI3REF: Determine If An SQL Statement Writes The Database
4247
** METHOD: sqlite3_stmt
4248
**
4249
** ^The sqlite3_stmt_readonly(X) interface returns true (non-zero) if
4250
** and only if the [prepared statement] X makes no direct changes to
4251
** the content of the database file.
4252
**
4253
** Note that [application-defined SQL functions] or
4254
** [virtual tables] might change the database indirectly as a side effect.
4255
** ^(For example, if an application defines a function "eval()" that
4256
** calls [sqlite3_exec()], then the following SQL statement would
4257
** change the database file through side-effects:
4258
**
4259
** <blockquote><pre>
4260
**    SELECT eval('DELETE FROM t1') FROM t2;
4261
** </pre></blockquote>
4262
**
4263
** But because the [SELECT] statement does not change the database file
4264
** directly, sqlite3_stmt_readonly() would still return true.)^
4265
**
4266
** ^Transaction control statements such as [BEGIN], [COMMIT], [ROLLBACK],
4267
** [SAVEPOINT], and [RELEASE] cause sqlite3_stmt_readonly() to return true,
4268
** since the statements themselves do not actually modify the database but
4269
** rather they control the timing of when other statements modify the
4270
** database.  ^The [ATTACH] and [DETACH] statements also cause
4271
** sqlite3_stmt_readonly() to return true since, while those statements
4272
** change the configuration of a database connection, they do not make
4273
** changes to the content of the database files on disk.
4274
** ^The sqlite3_stmt_readonly() interface returns true for [BEGIN] since
4275
** [BEGIN] merely sets internal flags, but the [BEGIN|BEGIN IMMEDIATE] and
4276
** [BEGIN|BEGIN EXCLUSIVE] commands do touch the database and so
4277
** sqlite3_stmt_readonly() returns false for those commands.
4278
**
4279
** ^This routine returns false if there is any possibility that the
4280
** statement might change the database file.  ^A false return does
4281
** not guarantee that the statement will change the database file.
4282
** ^For example, an UPDATE statement might have a WHERE clause that
4283
** makes it a no-op, but the sqlite3_stmt_readonly() result would still
4284
** be false.  ^Similarly, a CREATE TABLE IF NOT EXISTS statement is a
4285
** read-only no-op if the table already exists, but
4286
** sqlite3_stmt_readonly() still returns false for such a statement.
4287
**
4288
** ^If prepared statement X is an [EXPLAIN] or [EXPLAIN QUERY PLAN]
4289
** statement, then sqlite3_stmt_readonly(X) returns the same value as
4290
** if the EXPLAIN or EXPLAIN QUERY PLAN prefix were omitted.
4291
*/
4292
SQLITE_API int sqlite3_stmt_readonly(sqlite3_stmt *pStmt);
4293
4294
/*
4295
** CAPI3REF: Query The EXPLAIN Setting For A Prepared Statement
4296
** METHOD: sqlite3_stmt
4297
**
4298
** ^The sqlite3_stmt_isexplain(S) interface returns 1 if the
4299
** prepared statement S is an EXPLAIN statement, or 2 if the
4300
** statement S is an EXPLAIN QUERY PLAN.
4301
** ^The sqlite3_stmt_isexplain(S) interface returns 0 if S is
4302
** an ordinary statement or a NULL pointer.
4303
*/
4304
SQLITE_API int sqlite3_stmt_isexplain(sqlite3_stmt *pStmt);
4305
4306
/*
4307
** CAPI3REF: Determine If A Prepared Statement Has Been Reset
4308
** METHOD: sqlite3_stmt
4309
**
4310
** ^The sqlite3_stmt_busy(S) interface returns true (non-zero) if the
4311
** [prepared statement] S has been stepped at least once using
4312
** [sqlite3_step(S)] but has neither run to completion (returned
4313
** [SQLITE_DONE] from [sqlite3_step(S)]) nor
4314
** been reset using [sqlite3_reset(S)].  ^The sqlite3_stmt_busy(S)
4315
** interface returns false if S is a NULL pointer.  If S is not a
4316
** NULL pointer and is not a pointer to a valid [prepared statement]
4317
** object, then the behavior is undefined and probably undesirable.
4318
**
4319
** This interface can be used in combination [sqlite3_next_stmt()]
4320
** to locate all prepared statements associated with a database
4321
** connection that are in need of being reset.  This can be used,
4322
** for example, in diagnostic routines to search for prepared
4323
** statements that are holding a transaction open.
4324
*/
4325
SQLITE_API int sqlite3_stmt_busy(sqlite3_stmt*);
4326
4327
/*
4328
** CAPI3REF: Dynamically Typed Value Object
4329
** KEYWORDS: {protected sqlite3_value} {unprotected sqlite3_value}
4330
**
4331
** SQLite uses the sqlite3_value object to represent all values
4332
** that can be stored in a database table. SQLite uses dynamic typing
4333
** for the values it stores.  ^Values stored in sqlite3_value objects
4334
** can be integers, floating point values, strings, BLOBs, or NULL.
4335
**
4336
** An sqlite3_value object may be either "protected" or "unprotected".
4337
** Some interfaces require a protected sqlite3_value.  Other interfaces
4338
** will accept either a protected or an unprotected sqlite3_value.
4339
** Every interface that accepts sqlite3_value arguments specifies
4340
** whether or not it requires a protected sqlite3_value.  The
4341
** [sqlite3_value_dup()] interface can be used to construct a new
4342
** protected sqlite3_value from an unprotected sqlite3_value.
4343
**
4344
** The terms "protected" and "unprotected" refer to whether or not
4345
** a mutex is held.  An internal mutex is held for a protected
4346
** sqlite3_value object but no mutex is held for an unprotected
4347
** sqlite3_value object.  If SQLite is compiled to be single-threaded
4348
** (with [SQLITE_THREADSAFE=0] and with [sqlite3_threadsafe()] returning 0)
4349
** or if SQLite is run in one of reduced mutex modes
4350
** [SQLITE_CONFIG_SINGLETHREAD] or [SQLITE_CONFIG_MULTITHREAD]
4351
** then there is no distinction between protected and unprotected
4352
** sqlite3_value objects and they can be used interchangeably.  However,
4353
** for maximum code portability it is recommended that applications
4354
** still make the distinction between protected and unprotected
4355
** sqlite3_value objects even when not strictly required.
4356
**
4357
** ^The sqlite3_value objects that are passed as parameters into the
4358
** implementation of [application-defined SQL functions] are protected.
4359
** ^The sqlite3_value objects returned by [sqlite3_vtab_rhs_value()]
4360
** are protected.
4361
** ^The sqlite3_value object returned by
4362
** [sqlite3_column_value()] is unprotected.
4363
** Unprotected sqlite3_value objects may only be used as arguments
4364
** to [sqlite3_result_value()], [sqlite3_bind_value()], and
4365
** [sqlite3_value_dup()].
4366
** The [sqlite3_value_blob | sqlite3_value_type()] family of
4367
** interfaces require protected sqlite3_value objects.
4368
*/
4369
typedef struct sqlite3_value sqlite3_value;
4370
4371
/*
4372
** CAPI3REF: SQL Function Context Object
4373
**
4374
** The context in which an SQL function executes is stored in an
4375
** sqlite3_context object.  ^A pointer to an sqlite3_context object
4376
** is always first parameter to [application-defined SQL functions].
4377
** The application-defined SQL function implementation will pass this
4378
** pointer through into calls to [sqlite3_result_int | sqlite3_result()],
4379
** [sqlite3_aggregate_context()], [sqlite3_user_data()],
4380
** [sqlite3_context_db_handle()], [sqlite3_get_auxdata()],
4381
** and/or [sqlite3_set_auxdata()].
4382
*/
4383
typedef struct sqlite3_context sqlite3_context;
4384
4385
/*
4386
** CAPI3REF: Binding Values To Prepared Statements
4387
** KEYWORDS: {host parameter} {host parameters} {host parameter name}
4388
** KEYWORDS: {SQL parameter} {SQL parameters} {parameter binding}
4389
** METHOD: sqlite3_stmt
4390
**
4391
** ^(In the SQL statement text input to [sqlite3_prepare_v2()] and its variants,
4392
** literals may be replaced by a [parameter] that matches one of following
4393
** templates:
4394
**
4395
** <ul>
4396
** <li>  ?
4397
** <li>  ?NNN
4398
** <li>  :VVV
4399
** <li>  @VVV
4400
** <li>  $VVV
4401
** </ul>
4402
**
4403
** In the templates above, NNN represents an integer literal,
4404
** and VVV represents an alphanumeric identifier.)^  ^The values of these
4405
** parameters (also called "host parameter names" or "SQL parameters")
4406
** can be set using the sqlite3_bind_*() routines defined here.
4407
**
4408
** ^The first argument to the sqlite3_bind_*() routines is always
4409
** a pointer to the [sqlite3_stmt] object returned from
4410
** [sqlite3_prepare_v2()] or its variants.
4411
**
4412
** ^The second argument is the index of the SQL parameter to be set.
4413
** ^The leftmost SQL parameter has an index of 1.  ^When the same named
4414
** SQL parameter is used more than once, second and subsequent
4415
** occurrences have the same index as the first occurrence.
4416
** ^The index for named parameters can be looked up using the
4417
** [sqlite3_bind_parameter_index()] API if desired.  ^The index
4418
** for "?NNN" parameters is the value of NNN.
4419
** ^The NNN value must be between 1 and the [sqlite3_limit()]
4420
** parameter [SQLITE_LIMIT_VARIABLE_NUMBER] (default value: 32766).
4421
**
4422
** ^The third argument is the value to bind to the parameter.
4423
** ^If the third parameter to sqlite3_bind_text() or sqlite3_bind_text16()
4424
** or sqlite3_bind_blob() is a NULL pointer then the fourth parameter
4425
** is ignored and the end result is the same as sqlite3_bind_null().
4426
** ^If the third parameter to sqlite3_bind_text() is not NULL, then
4427
** it should be a pointer to well-formed UTF8 text.
4428
** ^If the third parameter to sqlite3_bind_text16() is not NULL, then
4429
** it should be a pointer to well-formed UTF16 text.
4430
** ^If the third parameter to sqlite3_bind_text64() is not NULL, then
4431
** it should be a pointer to a well-formed unicode string that is
4432
** either UTF8 if the sixth parameter is SQLITE_UTF8, or UTF16
4433
** otherwise.
4434
**
4435
** [[byte-order determination rules]] ^The byte-order of
4436
** UTF16 input text is determined by the byte-order mark (BOM, U+FEFF)
4437
** found in first character, which is removed, or in the absence of a BOM
4438
** the byte order is the native byte order of the host
4439
** machine for sqlite3_bind_text16() or the byte order specified in
4440
** the 6th parameter for sqlite3_bind_text64().)^
4441
** ^If UTF16 input text contains invalid unicode
4442
** characters, then SQLite might change those invalid characters
4443
** into the unicode replacement character: U+FFFD.
4444
**
4445
** ^(In those routines that have a fourth argument, its value is the
4446
** number of bytes in the parameter.  To be clear: the value is the
4447
** number of <u>bytes</u> in the value, not the number of characters.)^
4448
** ^If the fourth parameter to sqlite3_bind_text() or sqlite3_bind_text16()
4449
** is negative, then the length of the string is
4450
** the number of bytes up to the first zero terminator.
4451
** If the fourth parameter to sqlite3_bind_blob() is negative, then
4452
** the behavior is undefined.
4453
** If a non-negative fourth parameter is provided to sqlite3_bind_text()
4454
** or sqlite3_bind_text16() or sqlite3_bind_text64() then
4455
** that parameter must be the byte offset
4456
** where the NUL terminator would occur assuming the string were NUL
4457
** terminated.  If any NUL characters occurs at byte offsets less than
4458
** the value of the fourth parameter then the resulting string value will
4459
** contain embedded NULs.  The result of expressions involving strings
4460
** with embedded NULs is undefined.
4461
**
4462
** ^The fifth argument to the BLOB and string binding interfaces controls
4463
** or indicates the lifetime of the object referenced by the third parameter.
4464
** These three options exist:
4465
** ^ (1) A destructor to dispose of the BLOB or string after SQLite has finished
4466
** with it may be passed. ^It is called to dispose of the BLOB or string even
4467
** if the call to the bind API fails, except the destructor is not called if
4468
** the third parameter is a NULL pointer or the fourth parameter is negative.
4469
** ^ (2) The special constant, [SQLITE_STATIC], may be passsed to indicate that
4470
** the application remains responsible for disposing of the object. ^In this
4471
** case, the object and the provided pointer to it must remain valid until
4472
** either the prepared statement is finalized or the same SQL parameter is
4473
** bound to something else, whichever occurs sooner.
4474
** ^ (3) The constant, [SQLITE_TRANSIENT], may be passed to indicate that the
4475
** object is to be copied prior to the return from sqlite3_bind_*(). ^The
4476
** object and pointer to it must remain valid until then. ^SQLite will then
4477
** manage the lifetime of its private copy.
4478
**
4479
** ^The sixth argument to sqlite3_bind_text64() must be one of
4480
** [SQLITE_UTF8], [SQLITE_UTF16], [SQLITE_UTF16BE], or [SQLITE_UTF16LE]
4481
** to specify the encoding of the text in the third parameter.  If
4482
** the sixth argument to sqlite3_bind_text64() is not one of the
4483
** allowed values shown above, or if the text encoding is different
4484
** from the encoding specified by the sixth parameter, then the behavior
4485
** is undefined.
4486
**
4487
** ^The sqlite3_bind_zeroblob() routine binds a BLOB of length N that
4488
** is filled with zeroes.  ^A zeroblob uses a fixed amount of memory
4489
** (just an integer to hold its size) while it is being processed.
4490
** Zeroblobs are intended to serve as placeholders for BLOBs whose
4491
** content is later written using
4492
** [sqlite3_blob_open | incremental BLOB I/O] routines.
4493
** ^A negative value for the zeroblob results in a zero-length BLOB.
4494
**
4495
** ^The sqlite3_bind_pointer(S,I,P,T,D) routine causes the I-th parameter in
4496
** [prepared statement] S to have an SQL value of NULL, but to also be
4497
** associated with the pointer P of type T.  ^D is either a NULL pointer or
4498
** a pointer to a destructor function for P. ^SQLite will invoke the
4499
** destructor D with a single argument of P when it is finished using
4500
** P.  The T parameter should be a static string, preferably a string
4501
** literal. The sqlite3_bind_pointer() routine is part of the
4502
** [pointer passing interface] added for SQLite 3.20.0.
4503
**
4504
** ^If any of the sqlite3_bind_*() routines are called with a NULL pointer
4505
** for the [prepared statement] or with a prepared statement for which
4506
** [sqlite3_step()] has been called more recently than [sqlite3_reset()],
4507
** then the call will return [SQLITE_MISUSE].  If any sqlite3_bind_()
4508
** routine is passed a [prepared statement] that has been finalized, the
4509
** result is undefined and probably harmful.
4510
**
4511
** ^Bindings are not cleared by the [sqlite3_reset()] routine.
4512
** ^Unbound parameters are interpreted as NULL.
4513
**
4514
** ^The sqlite3_bind_* routines return [SQLITE_OK] on success or an
4515
** [error code] if anything goes wrong.
4516
** ^[SQLITE_TOOBIG] might be returned if the size of a string or BLOB
4517
** exceeds limits imposed by [sqlite3_limit]([SQLITE_LIMIT_LENGTH]) or
4518
** [SQLITE_MAX_LENGTH].
4519
** ^[SQLITE_RANGE] is returned if the parameter
4520
** index is out of range.  ^[SQLITE_NOMEM] is returned if malloc() fails.
4521
**
4522
** See also: [sqlite3_bind_parameter_count()],
4523
** [sqlite3_bind_parameter_name()], and [sqlite3_bind_parameter_index()].
4524
*/
4525
SQLITE_API int sqlite3_bind_blob(sqlite3_stmt*, int, const void*, int n, void(*)(void*));
4526
SQLITE_API int sqlite3_bind_blob64(sqlite3_stmt*, int, const void*, sqlite3_uint64,
4527
                        void(*)(void*));
4528
SQLITE_API int sqlite3_bind_double(sqlite3_stmt*, int, double);
4529
SQLITE_API int sqlite3_bind_int(sqlite3_stmt*, int, int);
4530
SQLITE_API int sqlite3_bind_int64(sqlite3_stmt*, int, sqlite3_int64);
4531
SQLITE_API int sqlite3_bind_null(sqlite3_stmt*, int);
4532
SQLITE_API int sqlite3_bind_text(sqlite3_stmt*,int,const char*,int,void(*)(void*));
4533
SQLITE_API int sqlite3_bind_text16(sqlite3_stmt*, int, const void*, int, void(*)(void*));
4534
SQLITE_API int sqlite3_bind_text64(sqlite3_stmt*, int, const char*, sqlite3_uint64,
4535
                         void(*)(void*), unsigned char encoding);
4536
SQLITE_API int sqlite3_bind_value(sqlite3_stmt*, int, const sqlite3_value*);
4537
SQLITE_API int sqlite3_bind_pointer(sqlite3_stmt*, int, void*, const char*,void(*)(void*));
4538
SQLITE_API int sqlite3_bind_zeroblob(sqlite3_stmt*, int, int n);
4539
SQLITE_API int sqlite3_bind_zeroblob64(sqlite3_stmt*, int, sqlite3_uint64);
4540
4541
/*
4542
** CAPI3REF: Number Of SQL Parameters
4543
** METHOD: sqlite3_stmt
4544
**
4545
** ^This routine can be used to find the number of [SQL parameters]
4546
** in a [prepared statement].  SQL parameters are tokens of the
4547
** form "?", "?NNN", ":AAA", "$AAA", or "@AAA" that serve as
4548
** placeholders for values that are [sqlite3_bind_blob | bound]
4549
** to the parameters at a later time.
4550
**
4551
** ^(This routine actually returns the index of the largest (rightmost)
4552
** parameter. For all forms except ?NNN, this will correspond to the
4553
** number of unique parameters.  If parameters of the ?NNN form are used,
4554
** there may be gaps in the list.)^
4555
**
4556
** See also: [sqlite3_bind_blob|sqlite3_bind()],
4557
** [sqlite3_bind_parameter_name()], and
4558
** [sqlite3_bind_parameter_index()].
4559
*/
4560
SQLITE_API int sqlite3_bind_parameter_count(sqlite3_stmt*);
4561
4562
/*
4563
** CAPI3REF: Name Of A Host Parameter
4564
** METHOD: sqlite3_stmt
4565
**
4566
** ^The sqlite3_bind_parameter_name(P,N) interface returns
4567
** the name of the N-th [SQL parameter] in the [prepared statement] P.
4568
** ^(SQL parameters of the form "?NNN" or ":AAA" or "@AAA" or "$AAA"
4569
** have a name which is the string "?NNN" or ":AAA" or "@AAA" or "$AAA"
4570
** respectively.
4571
** In other words, the initial ":" or "$" or "@" or "?"
4572
** is included as part of the name.)^
4573
** ^Parameters of the form "?" without a following integer have no name
4574
** and are referred to as "nameless" or "anonymous parameters".
4575
**
4576
** ^The first host parameter has an index of 1, not 0.
4577
**
4578
** ^If the value N is out of range or if the N-th parameter is
4579
** nameless, then NULL is returned.  ^The returned string is
4580
** always in UTF-8 encoding even if the named parameter was
4581
** originally specified as UTF-16 in [sqlite3_prepare16()],
4582
** [sqlite3_prepare16_v2()], or [sqlite3_prepare16_v3()].
4583
**
4584
** See also: [sqlite3_bind_blob|sqlite3_bind()],
4585
** [sqlite3_bind_parameter_count()], and
4586
** [sqlite3_bind_parameter_index()].
4587
*/
4588
SQLITE_API const char *sqlite3_bind_parameter_name(sqlite3_stmt*, int);
4589
4590
/*
4591
** CAPI3REF: Index Of A Parameter With A Given Name
4592
** METHOD: sqlite3_stmt
4593
**
4594
** ^Return the index of an SQL parameter given its name.  ^The
4595
** index value returned is suitable for use as the second
4596
** parameter to [sqlite3_bind_blob|sqlite3_bind()].  ^A zero
4597
** is returned if no matching parameter is found.  ^The parameter
4598
** name must be given in UTF-8 even if the original statement
4599
** was prepared from UTF-16 text using [sqlite3_prepare16_v2()] or
4600
** [sqlite3_prepare16_v3()].
4601
**
4602
** See also: [sqlite3_bind_blob|sqlite3_bind()],
4603
** [sqlite3_bind_parameter_count()], and
4604
** [sqlite3_bind_parameter_name()].
4605
*/
4606
SQLITE_API int sqlite3_bind_parameter_index(sqlite3_stmt*, const char *zName);
4607
4608
/*
4609
** CAPI3REF: Reset All Bindings On A Prepared Statement
4610
** METHOD: sqlite3_stmt
4611
**
4612
** ^Contrary to the intuition of many, [sqlite3_reset()] does not reset
4613
** the [sqlite3_bind_blob | bindings] on a [prepared statement].
4614
** ^Use this routine to reset all host parameters to NULL.
4615
*/
4616
SQLITE_API int sqlite3_clear_bindings(sqlite3_stmt*);
4617
4618
/*
4619
** CAPI3REF: Number Of Columns In A Result Set
4620
** METHOD: sqlite3_stmt
4621
**
4622
** ^Return the number of columns in the result set returned by the
4623
** [prepared statement]. ^If this routine returns 0, that means the
4624
** [prepared statement] returns no data (for example an [UPDATE]).
4625
** ^However, just because this routine returns a positive number does not
4626
** mean that one or more rows of data will be returned.  ^A SELECT statement
4627
** will always have a positive sqlite3_column_count() but depending on the
4628
** WHERE clause constraints and the table content, it might return no rows.
4629
**
4630
** See also: [sqlite3_data_count()]
4631
*/
4632
SQLITE_API int sqlite3_column_count(sqlite3_stmt *pStmt);
4633
4634
/*
4635
** CAPI3REF: Column Names In A Result Set
4636
** METHOD: sqlite3_stmt
4637
**
4638
** ^These routines return the name assigned to a particular column
4639
** in the result set of a [SELECT] statement.  ^The sqlite3_column_name()
4640
** interface returns a pointer to a zero-terminated UTF-8 string
4641
** and sqlite3_column_name16() returns a pointer to a zero-terminated
4642
** UTF-16 string.  ^The first parameter is the [prepared statement]
4643
** that implements the [SELECT] statement. ^The second parameter is the
4644
** column number.  ^The leftmost column is number 0.
4645
**
4646
** ^The returned string pointer is valid until either the [prepared statement]
4647
** is destroyed by [sqlite3_finalize()] or until the statement is automatically
4648
** reprepared by the first call to [sqlite3_step()] for a particular run
4649
** or until the next call to
4650
** sqlite3_column_name() or sqlite3_column_name16() on the same column.
4651
**
4652
** ^If sqlite3_malloc() fails during the processing of either routine
4653
** (for example during a conversion from UTF-8 to UTF-16) then a
4654
** NULL pointer is returned.
4655
**
4656
** ^The name of a result column is the value of the "AS" clause for
4657
** that column, if there is an AS clause.  If there is no AS clause
4658
** then the name of the column is unspecified and may change from
4659
** one release of SQLite to the next.
4660
*/
4661
SQLITE_API const char *sqlite3_column_name(sqlite3_stmt*, int N);
4662
SQLITE_API const void *sqlite3_column_name16(sqlite3_stmt*, int N);
4663
4664
/*
4665
** CAPI3REF: Source Of Data In A Query Result
4666
** METHOD: sqlite3_stmt
4667
**
4668
** ^These routines provide a means to determine the database, table, and
4669
** table column that is the origin of a particular result column in
4670
** [SELECT] statement.
4671
** ^The name of the database or table or column can be returned as
4672
** either a UTF-8 or UTF-16 string.  ^The _database_ routines return
4673
** the database name, the _table_ routines return the table name, and
4674
** the origin_ routines return the column name.
4675
** ^The returned string is valid until the [prepared statement] is destroyed
4676
** using [sqlite3_finalize()] or until the statement is automatically
4677
** reprepared by the first call to [sqlite3_step()] for a particular run
4678
** or until the same information is requested
4679
** again in a different encoding.
4680
**
4681
** ^The names returned are the original un-aliased names of the
4682
** database, table, and column.
4683
**
4684
** ^The first argument to these interfaces is a [prepared statement].
4685
** ^These functions return information about the Nth result column returned by
4686
** the statement, where N is the second function argument.
4687
** ^The left-most column is column 0 for these routines.
4688
**
4689
** ^If the Nth column returned by the statement is an expression or
4690
** subquery and is not a column value, then all of these functions return
4691
** NULL.  ^These routines might also return NULL if a memory allocation error
4692
** occurs.  ^Otherwise, they return the name of the attached database, table,
4693
** or column that query result column was extracted from.
4694
**
4695
** ^As with all other SQLite APIs, those whose names end with "16" return
4696
** UTF-16 encoded strings and the other functions return UTF-8.
4697
**
4698
** ^These APIs are only available if the library was compiled with the
4699
** [SQLITE_ENABLE_COLUMN_METADATA] C-preprocessor symbol.
4700
**
4701
** If two or more threads call one or more
4702
** [sqlite3_column_database_name | column metadata interfaces]
4703
** for the same [prepared statement] and result column
4704
** at the same time then the results are undefined.
4705
*/
4706
SQLITE_API const char *sqlite3_column_database_name(sqlite3_stmt*,int);
4707
SQLITE_API const void *sqlite3_column_database_name16(sqlite3_stmt*,int);
4708
SQLITE_API const char *sqlite3_column_table_name(sqlite3_stmt*,int);
4709
SQLITE_API const void *sqlite3_column_table_name16(sqlite3_stmt*,int);
4710
SQLITE_API const char *sqlite3_column_origin_name(sqlite3_stmt*,int);
4711
SQLITE_API const void *sqlite3_column_origin_name16(sqlite3_stmt*,int);
4712
4713
/*
4714
** CAPI3REF: Declared Datatype Of A Query Result
4715
** METHOD: sqlite3_stmt
4716
**
4717
** ^(The first parameter is a [prepared statement].
4718
** If this statement is a [SELECT] statement and the Nth column of the
4719
** returned result set of that [SELECT] is a table column (not an
4720
** expression or subquery) then the declared type of the table
4721
** column is returned.)^  ^If the Nth column of the result set is an
4722
** expression or subquery, then a NULL pointer is returned.
4723
** ^The returned string is always UTF-8 encoded.
4724
**
4725
** ^(For example, given the database schema:
4726
**
4727
** CREATE TABLE t1(c1 VARIANT);
4728
**
4729
** and the following statement to be compiled:
4730
**
4731
** SELECT c1 + 1, c1 FROM t1;
4732
**
4733
** this routine would return the string "VARIANT" for the second result
4734
** column (i==1), and a NULL pointer for the first result column (i==0).)^
4735
**
4736
** ^SQLite uses dynamic run-time typing.  ^So just because a column
4737
** is declared to contain a particular type does not mean that the
4738
** data stored in that column is of the declared type.  SQLite is
4739
** strongly typed, but the typing is dynamic not static.  ^Type
4740
** is associated with individual values, not with the containers
4741
** used to hold those values.
4742
*/
4743
SQLITE_API const char *sqlite3_column_decltype(sqlite3_stmt*,int);
4744
SQLITE_API const void *sqlite3_column_decltype16(sqlite3_stmt*,int);
4745
4746
/*
4747
** CAPI3REF: Evaluate An SQL Statement
4748
** METHOD: sqlite3_stmt
4749
**
4750
** After a [prepared statement] has been prepared using any of
4751
** [sqlite3_prepare_v2()], [sqlite3_prepare_v3()], [sqlite3_prepare16_v2()],
4752
** or [sqlite3_prepare16_v3()] or one of the legacy
4753
** interfaces [sqlite3_prepare()] or [sqlite3_prepare16()], this function
4754
** must be called one or more times to evaluate the statement.
4755
**
4756
** The details of the behavior of the sqlite3_step() interface depend
4757
** on whether the statement was prepared using the newer "vX" interfaces
4758
** [sqlite3_prepare_v3()], [sqlite3_prepare_v2()], [sqlite3_prepare16_v3()],
4759
** [sqlite3_prepare16_v2()] or the older legacy
4760
** interfaces [sqlite3_prepare()] and [sqlite3_prepare16()].  The use of the
4761
** new "vX" interface is recommended for new applications but the legacy
4762
** interface will continue to be supported.
4763
**
4764
** ^In the legacy interface, the return value will be either [SQLITE_BUSY],
4765
** [SQLITE_DONE], [SQLITE_ROW], [SQLITE_ERROR], or [SQLITE_MISUSE].
4766
** ^With the "v2" interface, any of the other [result codes] or
4767
** [extended result codes] might be returned as well.
4768
**
4769
** ^[SQLITE_BUSY] means that the database engine was unable to acquire the
4770
** database locks it needs to do its job.  ^If the statement is a [COMMIT]
4771
** or occurs outside of an explicit transaction, then you can retry the
4772
** statement.  If the statement is not a [COMMIT] and occurs within an
4773
** explicit transaction then you should rollback the transaction before
4774
** continuing.
4775
**
4776
** ^[SQLITE_DONE] means that the statement has finished executing
4777
** successfully.  sqlite3_step() should not be called again on this virtual
4778
** machine without first calling [sqlite3_reset()] to reset the virtual
4779
** machine back to its initial state.
4780
**
4781
** ^If the SQL statement being executed returns any data, then [SQLITE_ROW]
4782
** is returned each time a new row of data is ready for processing by the
4783
** caller. The values may be accessed using the [column access functions].
4784
** sqlite3_step() is called again to retrieve the next row of data.
4785
**
4786
** ^[SQLITE_ERROR] means that a run-time error (such as a constraint
4787
** violation) has occurred.  sqlite3_step() should not be called again on
4788
** the VM. More information may be found by calling [sqlite3_errmsg()].
4789
** ^With the legacy interface, a more specific error code (for example,
4790
** [SQLITE_INTERRUPT], [SQLITE_SCHEMA], [SQLITE_CORRUPT], and so forth)
4791
** can be obtained by calling [sqlite3_reset()] on the
4792
** [prepared statement].  ^In the "v2" interface,
4793
** the more specific error code is returned directly by sqlite3_step().
4794
**
4795
** [SQLITE_MISUSE] means that the this routine was called inappropriately.
4796
** Perhaps it was called on a [prepared statement] that has
4797
** already been [sqlite3_finalize | finalized] or on one that had
4798
** previously returned [SQLITE_ERROR] or [SQLITE_DONE].  Or it could
4799
** be the case that the same database connection is being used by two or
4800
** more threads at the same moment in time.
4801
**
4802
** For all versions of SQLite up to and including 3.6.23.1, a call to
4803
** [sqlite3_reset()] was required after sqlite3_step() returned anything
4804
** other than [SQLITE_ROW] before any subsequent invocation of
4805
** sqlite3_step().  Failure to reset the prepared statement using
4806
** [sqlite3_reset()] would result in an [SQLITE_MISUSE] return from
4807
** sqlite3_step().  But after [version 3.6.23.1] ([dateof:3.6.23.1],
4808
** sqlite3_step() began
4809
** calling [sqlite3_reset()] automatically in this circumstance rather
4810
** than returning [SQLITE_MISUSE].  This is not considered a compatibility
4811
** break because any application that ever receives an SQLITE_MISUSE error
4812
** is broken by definition.  The [SQLITE_OMIT_AUTORESET] compile-time option
4813
** can be used to restore the legacy behavior.
4814
**
4815
** <b>Goofy Interface Alert:</b> In the legacy interface, the sqlite3_step()
4816
** API always returns a generic error code, [SQLITE_ERROR], following any
4817
** error other than [SQLITE_BUSY] and [SQLITE_MISUSE].  You must call
4818
** [sqlite3_reset()] or [sqlite3_finalize()] in order to find one of the
4819
** specific [error codes] that better describes the error.
4820
** We admit that this is a goofy design.  The problem has been fixed
4821
** with the "v2" interface.  If you prepare all of your SQL statements
4822
** using [sqlite3_prepare_v3()] or [sqlite3_prepare_v2()]
4823
** or [sqlite3_prepare16_v2()] or [sqlite3_prepare16_v3()] instead
4824
** of the legacy [sqlite3_prepare()] and [sqlite3_prepare16()] interfaces,
4825
** then the more specific [error codes] are returned directly
4826
** by sqlite3_step().  The use of the "vX" interfaces is recommended.
4827
*/
4828
SQLITE_API int sqlite3_step(sqlite3_stmt*);
4829
4830
/*
4831
** CAPI3REF: Number of columns in a result set
4832
** METHOD: sqlite3_stmt
4833
**
4834
** ^The sqlite3_data_count(P) interface returns the number of columns in the
4835
** current row of the result set of [prepared statement] P.
4836
** ^If prepared statement P does not have results ready to return
4837
** (via calls to the [sqlite3_column_int | sqlite3_column()] family of
4838
** interfaces) then sqlite3_data_count(P) returns 0.
4839
** ^The sqlite3_data_count(P) routine also returns 0 if P is a NULL pointer.
4840
** ^The sqlite3_data_count(P) routine returns 0 if the previous call to
4841
** [sqlite3_step](P) returned [SQLITE_DONE].  ^The sqlite3_data_count(P)
4842
** will return non-zero if previous call to [sqlite3_step](P) returned
4843
** [SQLITE_ROW], except in the case of the [PRAGMA incremental_vacuum]
4844
** where it always returns zero since each step of that multi-step
4845
** pragma returns 0 columns of data.
4846
**
4847
** See also: [sqlite3_column_count()]
4848
*/
4849
SQLITE_API int sqlite3_data_count(sqlite3_stmt *pStmt);
4850
4851
/*
4852
** CAPI3REF: Fundamental Datatypes
4853
** KEYWORDS: SQLITE_TEXT
4854
**
4855
** ^(Every value in SQLite has one of five fundamental datatypes:
4856
**
4857
** <ul>
4858
** <li> 64-bit signed integer
4859
** <li> 64-bit IEEE floating point number
4860
** <li> string
4861
** <li> BLOB
4862
** <li> NULL
4863
** </ul>)^
4864
**
4865
** These constants are codes for each of those types.
4866
**
4867
** Note that the SQLITE_TEXT constant was also used in SQLite version 2
4868
** for a completely different meaning.  Software that links against both
4869
** SQLite version 2 and SQLite version 3 should use SQLITE3_TEXT, not
4870
** SQLITE_TEXT.
4871
*/
4872
979
#define SQLITE_INTEGER  1
4873
202
#define SQLITE_FLOAT    2
4874
5
#define SQLITE_BLOB     4
4875
922
#define SQLITE_NULL     5
4876
#ifdef SQLITE_TEXT
4877
# undef SQLITE_TEXT
4878
#else
4879
213
# define SQLITE_TEXT     3
4880
#endif
4881
#define SQLITE3_TEXT     3
4882
4883
/*
4884
** CAPI3REF: Result Values From A Query
4885
** KEYWORDS: {column access functions}
4886
** METHOD: sqlite3_stmt
4887
**
4888
** <b>Summary:</b>
4889
** <blockquote><table border=0 cellpadding=0 cellspacing=0>
4890
** <tr><td><b>sqlite3_column_blob</b><td>&rarr;<td>BLOB result
4891
** <tr><td><b>sqlite3_column_double</b><td>&rarr;<td>REAL result
4892
** <tr><td><b>sqlite3_column_int</b><td>&rarr;<td>32-bit INTEGER result
4893
** <tr><td><b>sqlite3_column_int64</b><td>&rarr;<td>64-bit INTEGER result
4894
** <tr><td><b>sqlite3_column_text</b><td>&rarr;<td>UTF-8 TEXT result
4895
** <tr><td><b>sqlite3_column_text16</b><td>&rarr;<td>UTF-16 TEXT result
4896
** <tr><td><b>sqlite3_column_value</b><td>&rarr;<td>The result as an
4897
** [sqlite3_value|unprotected sqlite3_value] object.
4898
** <tr><td>&nbsp;<td>&nbsp;<td>&nbsp;
4899
** <tr><td><b>sqlite3_column_bytes</b><td>&rarr;<td>Size of a BLOB
4900
** or a UTF-8 TEXT result in bytes
4901
** <tr><td><b>sqlite3_column_bytes16&nbsp;&nbsp;</b>
4902
** <td>&rarr;&nbsp;&nbsp;<td>Size of UTF-16
4903
** TEXT in bytes
4904
** <tr><td><b>sqlite3_column_type</b><td>&rarr;<td>Default
4905
** datatype of the result
4906
** </table></blockquote>
4907
**
4908
** <b>Details:</b>
4909
**
4910
** ^These routines return information about a single column of the current
4911
** result row of a query.  ^In every case the first argument is a pointer
4912
** to the [prepared statement] that is being evaluated (the [sqlite3_stmt*]
4913
** that was returned from [sqlite3_prepare_v2()] or one of its variants)
4914
** and the second argument is the index of the column for which information
4915
** should be returned. ^The leftmost column of the result set has the index 0.
4916
** ^The number of columns in the result can be determined using
4917
** [sqlite3_column_count()].
4918
**
4919
** If the SQL statement does not currently point to a valid row, or if the
4920
** column index is out of range, the result is undefined.
4921
** These routines may only be called when the most recent call to
4922
** [sqlite3_step()] has returned [SQLITE_ROW] and neither
4923
** [sqlite3_reset()] nor [sqlite3_finalize()] have been called subsequently.
4924
** If any of these routines are called after [sqlite3_reset()] or
4925
** [sqlite3_finalize()] or after [sqlite3_step()] has returned
4926
** something other than [SQLITE_ROW], the results are undefined.
4927
** If [sqlite3_step()] or [sqlite3_reset()] or [sqlite3_finalize()]
4928
** are called from a different thread while any of these routines
4929
** are pending, then the results are undefined.
4930
**
4931
** The first six interfaces (_blob, _double, _int, _int64, _text, and _text16)
4932
** each return the value of a result column in a specific data format.  If
4933
** the result column is not initially in the requested format (for example,
4934
** if the query returns an integer but the sqlite3_column_text() interface
4935
** is used to extract the value) then an automatic type conversion is performed.
4936
**
4937
** ^The sqlite3_column_type() routine returns the
4938
** [SQLITE_INTEGER | datatype code] for the initial data type
4939
** of the result column.  ^The returned value is one of [SQLITE_INTEGER],
4940
** [SQLITE_FLOAT], [SQLITE_TEXT], [SQLITE_BLOB], or [SQLITE_NULL].
4941
** The return value of sqlite3_column_type() can be used to decide which
4942
** of the first six interface should be used to extract the column value.
4943
** The value returned by sqlite3_column_type() is only meaningful if no
4944
** automatic type conversions have occurred for the value in question.
4945
** After a type conversion, the result of calling sqlite3_column_type()
4946
** is undefined, though harmless.  Future
4947
** versions of SQLite may change the behavior of sqlite3_column_type()
4948
** following a type conversion.
4949
**
4950
** If the result is a BLOB or a TEXT string, then the sqlite3_column_bytes()
4951
** or sqlite3_column_bytes16() interfaces can be used to determine the size
4952
** of that BLOB or string.
4953
**
4954
** ^If the result is a BLOB or UTF-8 string then the sqlite3_column_bytes()
4955
** routine returns the number of bytes in that BLOB or string.
4956
** ^If the result is a UTF-16 string, then sqlite3_column_bytes() converts
4957
** the string to UTF-8 and then returns the number of bytes.
4958
** ^If the result is a numeric value then sqlite3_column_bytes() uses
4959
** [sqlite3_snprintf()] to convert that value to a UTF-8 string and returns
4960
** the number of bytes in that string.
4961
** ^If the result is NULL, then sqlite3_column_bytes() returns zero.
4962
**
4963
** ^If the result is a BLOB or UTF-16 string then the sqlite3_column_bytes16()
4964
** routine returns the number of bytes in that BLOB or string.
4965
** ^If the result is a UTF-8 string, then sqlite3_column_bytes16() converts
4966
** the string to UTF-16 and then returns the number of bytes.
4967
** ^If the result is a numeric value then sqlite3_column_bytes16() uses
4968
** [sqlite3_snprintf()] to convert that value to a UTF-16 string and returns
4969
** the number of bytes in that string.
4970
** ^If the result is NULL, then sqlite3_column_bytes16() returns zero.
4971
**
4972
** ^The values returned by [sqlite3_column_bytes()] and
4973
** [sqlite3_column_bytes16()] do not include the zero terminators at the end
4974
** of the string.  ^For clarity: the values returned by
4975
** [sqlite3_column_bytes()] and [sqlite3_column_bytes16()] are the number of
4976
** bytes in the string, not the number of characters.
4977
**
4978
** ^Strings returned by sqlite3_column_text() and sqlite3_column_text16(),
4979
** even empty strings, are always zero-terminated.  ^The return
4980
** value from sqlite3_column_blob() for a zero-length BLOB is a NULL pointer.
4981
**
4982
** ^Strings returned by sqlite3_column_text16() always have the endianness
4983
** which is native to the platform, regardless of the text encoding set
4984
** for the database.
4985
**
4986
** <b>Warning:</b> ^The object returned by [sqlite3_column_value()] is an
4987
** [unprotected sqlite3_value] object.  In a multithreaded environment,
4988
** an unprotected sqlite3_value object may only be used safely with
4989
** [sqlite3_bind_value()] and [sqlite3_result_value()].
4990
** If the [unprotected sqlite3_value] object returned by
4991
** [sqlite3_column_value()] is used in any other way, including calls
4992
** to routines like [sqlite3_value_int()], [sqlite3_value_text()],
4993
** or [sqlite3_value_bytes()], the behavior is not threadsafe.
4994
** Hence, the sqlite3_column_value() interface
4995
** is normally only useful within the implementation of
4996
** [application-defined SQL functions] or [virtual tables], not within
4997
** top-level application code.
4998
**
4999
** These routines may attempt to convert the datatype of the result.
5000
** ^For example, if the internal representation is FLOAT and a text result
5001
** is requested, [sqlite3_snprintf()] is used internally to perform the
5002
** conversion automatically.  ^(The following table details the conversions
5003
** that are applied:
5004
**
5005
** <blockquote>
5006
** <table border="1">
5007
** <tr><th> Internal<br>Type <th> Requested<br>Type <th>  Conversion
5008
**
5009
** <tr><td>  NULL    <td> INTEGER   <td> Result is 0
5010
** <tr><td>  NULL    <td>  FLOAT    <td> Result is 0.0
5011
** <tr><td>  NULL    <td>   TEXT    <td> Result is a NULL pointer
5012
** <tr><td>  NULL    <td>   BLOB    <td> Result is a NULL pointer
5013
** <tr><td> INTEGER  <td>  FLOAT    <td> Convert from integer to float
5014
** <tr><td> INTEGER  <td>   TEXT    <td> ASCII rendering of the integer
5015
** <tr><td> INTEGER  <td>   BLOB    <td> Same as INTEGER->TEXT
5016
** <tr><td>  FLOAT   <td> INTEGER   <td> [CAST] to INTEGER
5017
** <tr><td>  FLOAT   <td>   TEXT    <td> ASCII rendering of the float
5018
** <tr><td>  FLOAT   <td>   BLOB    <td> [CAST] to BLOB
5019
** <tr><td>  TEXT    <td> INTEGER   <td> [CAST] to INTEGER
5020
** <tr><td>  TEXT    <td>  FLOAT    <td> [CAST] to REAL
5021
** <tr><td>  TEXT    <td>   BLOB    <td> No change
5022
** <tr><td>  BLOB    <td> INTEGER   <td> [CAST] to INTEGER
5023
** <tr><td>  BLOB    <td>  FLOAT    <td> [CAST] to REAL
5024
** <tr><td>  BLOB    <td>   TEXT    <td> [CAST] to TEXT, ensure zero terminator
5025
** </table>
5026
** </blockquote>)^
5027
**
5028
** Note that when type conversions occur, pointers returned by prior
5029
** calls to sqlite3_column_blob(), sqlite3_column_text(), and/or
5030
** sqlite3_column_text16() may be invalidated.
5031
** Type conversions and pointer invalidations might occur
5032
** in the following cases:
5033
**
5034
** <ul>
5035
** <li> The initial content is a BLOB and sqlite3_column_text() or
5036
**      sqlite3_column_text16() is called.  A zero-terminator might
5037
**      need to be added to the string.</li>
5038
** <li> The initial content is UTF-8 text and sqlite3_column_bytes16() or
5039
**      sqlite3_column_text16() is called.  The content must be converted
5040
**      to UTF-16.</li>
5041
** <li> The initial content is UTF-16 text and sqlite3_column_bytes() or
5042
**      sqlite3_column_text() is called.  The content must be converted
5043
**      to UTF-8.</li>
5044
** </ul>
5045
**
5046
** ^Conversions between UTF-16be and UTF-16le are always done in place and do
5047
** not invalidate a prior pointer, though of course the content of the buffer
5048
** that the prior pointer references will have been modified.  Other kinds
5049
** of conversion are done in place when it is possible, but sometimes they
5050
** are not possible and in those cases prior pointers are invalidated.
5051
**
5052
** The safest policy is to invoke these routines
5053
** in one of the following ways:
5054
**
5055
** <ul>
5056
**  <li>sqlite3_column_text() followed by sqlite3_column_bytes()</li>
5057
**  <li>sqlite3_column_blob() followed by sqlite3_column_bytes()</li>
5058
**  <li>sqlite3_column_text16() followed by sqlite3_column_bytes16()</li>
5059
** </ul>
5060
**
5061
** In other words, you should call sqlite3_column_text(),
5062
** sqlite3_column_blob(), or sqlite3_column_text16() first to force the result
5063
** into the desired format, then invoke sqlite3_column_bytes() or
5064
** sqlite3_column_bytes16() to find the size of the result.  Do not mix calls
5065
** to sqlite3_column_text() or sqlite3_column_blob() with calls to
5066
** sqlite3_column_bytes16(), and do not mix calls to sqlite3_column_text16()
5067
** with calls to sqlite3_column_bytes().
5068
**
5069
** ^The pointers returned are valid until a type conversion occurs as
5070
** described above, or until [sqlite3_step()] or [sqlite3_reset()] or
5071
** [sqlite3_finalize()] is called.  ^The memory space used to hold strings
5072
** and BLOBs is freed automatically.  Do not pass the pointers returned
5073
** from [sqlite3_column_blob()], [sqlite3_column_text()], etc. into
5074
** [sqlite3_free()].
5075
**
5076
** As long as the input parameters are correct, these routines will only
5077
** fail if an out-of-memory error occurs during a format conversion.
5078
** Only the following subset of interfaces are subject to out-of-memory
5079
** errors:
5080
**
5081
** <ul>
5082
** <li> sqlite3_column_blob()
5083
** <li> sqlite3_column_text()
5084
** <li> sqlite3_column_text16()
5085
** <li> sqlite3_column_bytes()
5086
** <li> sqlite3_column_bytes16()
5087
** </ul>
5088
**
5089
** If an out-of-memory error occurs, then the return value from these
5090
** routines is the same as if the column had contained an SQL NULL value.
5091
** Valid SQL NULL returns can be distinguished from out-of-memory errors
5092
** by invoking the [sqlite3_errcode()] immediately after the suspect
5093
** return value is obtained and before any
5094
** other SQLite interface is called on the same [database connection].
5095
*/
5096
SQLITE_API const void *sqlite3_column_blob(sqlite3_stmt*, int iCol);
5097
SQLITE_API double sqlite3_column_double(sqlite3_stmt*, int iCol);
5098
SQLITE_API int sqlite3_column_int(sqlite3_stmt*, int iCol);
5099
SQLITE_API sqlite3_int64 sqlite3_column_int64(sqlite3_stmt*, int iCol);
5100
SQLITE_API const unsigned char *sqlite3_column_text(sqlite3_stmt*, int iCol);
5101
SQLITE_API const void *sqlite3_column_text16(sqlite3_stmt*, int iCol);
5102
SQLITE_API sqlite3_value *sqlite3_column_value(sqlite3_stmt*, int iCol);
5103
SQLITE_API int sqlite3_column_bytes(sqlite3_stmt*, int iCol);
5104
SQLITE_API int sqlite3_column_bytes16(sqlite3_stmt*, int iCol);
5105
SQLITE_API int sqlite3_column_type(sqlite3_stmt*, int iCol);
5106
5107
/*
5108
** CAPI3REF: Destroy A Prepared Statement Object
5109
** DESTRUCTOR: sqlite3_stmt
5110
**
5111
** ^The sqlite3_finalize() function is called to delete a [prepared statement].
5112
** ^If the most recent evaluation of the statement encountered no errors
5113
** or if the statement is never been evaluated, then sqlite3_finalize() returns
5114
** SQLITE_OK.  ^If the most recent evaluation of statement S failed, then
5115
** sqlite3_finalize(S) returns the appropriate [error code] or
5116
** [extended error code].
5117
**
5118
** ^The sqlite3_finalize(S) routine can be called at any point during
5119
** the life cycle of [prepared statement] S:
5120
** before statement S is ever evaluated, after
5121
** one or more calls to [sqlite3_reset()], or after any call
5122
** to [sqlite3_step()] regardless of whether or not the statement has
5123
** completed execution.
5124
**
5125
** ^Invoking sqlite3_finalize() on a NULL pointer is a harmless no-op.
5126
**
5127
** The application must finalize every [prepared statement] in order to avoid
5128
** resource leaks.  It is a grievous error for the application to try to use
5129
** a prepared statement after it has been finalized.  Any use of a prepared
5130
** statement after it has been finalized can result in undefined and
5131
** undesirable behavior such as segfaults and heap corruption.
5132
*/
5133
SQLITE_API int sqlite3_finalize(sqlite3_stmt *pStmt);
5134
5135
/*
5136
** CAPI3REF: Reset A Prepared Statement Object
5137
** METHOD: sqlite3_stmt
5138
**
5139
** The sqlite3_reset() function is called to reset a [prepared statement]
5140
** object back to its initial state, ready to be re-executed.
5141
** ^Any SQL statement variables that had values bound to them using
5142
** the [sqlite3_bind_blob | sqlite3_bind_*() API] retain their values.
5143
** Use [sqlite3_clear_bindings()] to reset the bindings.
5144
**
5145
** ^The [sqlite3_reset(S)] interface resets the [prepared statement] S
5146
** back to the beginning of its program.
5147
**
5148
** ^If the most recent call to [sqlite3_step(S)] for the
5149
** [prepared statement] S returned [SQLITE_ROW] or [SQLITE_DONE],
5150
** or if [sqlite3_step(S)] has never before been called on S,
5151
** then [sqlite3_reset(S)] returns [SQLITE_OK].
5152
**
5153
** ^If the most recent call to [sqlite3_step(S)] for the
5154
** [prepared statement] S indicated an error, then
5155
** [sqlite3_reset(S)] returns an appropriate [error code].
5156
**
5157
** ^The [sqlite3_reset(S)] interface does not change the values
5158
** of any [sqlite3_bind_blob|bindings] on the [prepared statement] S.
5159
*/
5160
SQLITE_API int sqlite3_reset(sqlite3_stmt *pStmt);
5161
5162
/*
5163
** CAPI3REF: Create Or Redefine SQL Functions
5164
** KEYWORDS: {function creation routines}
5165
** METHOD: sqlite3
5166
**
5167
** ^These functions (collectively known as "function creation routines")
5168
** are used to add SQL functions or aggregates or to redefine the behavior
5169
** of existing SQL functions or aggregates. The only differences between
5170
** the three "sqlite3_create_function*" routines are the text encoding
5171
** expected for the second parameter (the name of the function being
5172
** created) and the presence or absence of a destructor callback for
5173
** the application data pointer. Function sqlite3_create_window_function()
5174
** is similar, but allows the user to supply the extra callback functions
5175
** needed by [aggregate window functions].
5176
**
5177
** ^The first parameter is the [database connection] to which the SQL
5178
** function is to be added.  ^If an application uses more than one database
5179
** connection then application-defined SQL functions must be added
5180
** to each database connection separately.
5181
**
5182
** ^The second parameter is the name of the SQL function to be created or
5183
** redefined.  ^The length of the name is limited to 255 bytes in a UTF-8
5184
** representation, exclusive of the zero-terminator.  ^Note that the name
5185
** length limit is in UTF-8 bytes, not characters nor UTF-16 bytes.
5186
** ^Any attempt to create a function with a longer name
5187
** will result in [SQLITE_MISUSE] being returned.
5188
**
5189
** ^The third parameter (nArg)
5190
** is the number of arguments that the SQL function or
5191
** aggregate takes. ^If this parameter is -1, then the SQL function or
5192
** aggregate may take any number of arguments between 0 and the limit
5193
** set by [sqlite3_limit]([SQLITE_LIMIT_FUNCTION_ARG]).  If the third
5194
** parameter is less than -1 or greater than 127 then the behavior is
5195
** undefined.
5196
**
5197
** ^The fourth parameter, eTextRep, specifies what
5198
** [SQLITE_UTF8 | text encoding] this SQL function prefers for
5199
** its parameters.  The application should set this parameter to
5200
** [SQLITE_UTF16LE] if the function implementation invokes
5201
** [sqlite3_value_text16le()] on an input, or [SQLITE_UTF16BE] if the
5202
** implementation invokes [sqlite3_value_text16be()] on an input, or
5203
** [SQLITE_UTF16] if [sqlite3_value_text16()] is used, or [SQLITE_UTF8]
5204
** otherwise.  ^The same SQL function may be registered multiple times using
5205
** different preferred text encodings, with different implementations for
5206
** each encoding.
5207
** ^When multiple implementations of the same function are available, SQLite
5208
** will pick the one that involves the least amount of data conversion.
5209
**
5210
** ^The fourth parameter may optionally be ORed with [SQLITE_DETERMINISTIC]
5211
** to signal that the function will always return the same result given
5212
** the same inputs within a single SQL statement.  Most SQL functions are
5213
** deterministic.  The built-in [random()] SQL function is an example of a
5214
** function that is not deterministic.  The SQLite query planner is able to
5215
** perform additional optimizations on deterministic functions, so use
5216
** of the [SQLITE_DETERMINISTIC] flag is recommended where possible.
5217
**
5218
** ^The fourth parameter may also optionally include the [SQLITE_DIRECTONLY]
5219
** flag, which if present prevents the function from being invoked from
5220
** within VIEWs, TRIGGERs, CHECK constraints, generated column expressions,
5221
** index expressions, or the WHERE clause of partial indexes.
5222
**
5223
** For best security, the [SQLITE_DIRECTONLY] flag is recommended for
5224
** all application-defined SQL functions that do not need to be
5225
** used inside of triggers, view, CHECK constraints, or other elements of
5226
** the database schema.  This flags is especially recommended for SQL
5227
** functions that have side effects or reveal internal application state.
5228
** Without this flag, an attacker might be able to modify the schema of
5229
** a database file to include invocations of the function with parameters
5230
** chosen by the attacker, which the application will then execute when
5231
** the database file is opened and read.
5232
**
5233
** ^(The fifth parameter is an arbitrary pointer.  The implementation of the
5234
** function can gain access to this pointer using [sqlite3_user_data()].)^
5235
**
5236
** ^The sixth, seventh and eighth parameters passed to the three
5237
** "sqlite3_create_function*" functions, xFunc, xStep and xFinal, are
5238
** pointers to C-language functions that implement the SQL function or
5239
** aggregate. ^A scalar SQL function requires an implementation of the xFunc
5240
** callback only; NULL pointers must be passed as the xStep and xFinal
5241
** parameters. ^An aggregate SQL function requires an implementation of xStep
5242
** and xFinal and NULL pointer must be passed for xFunc. ^To delete an existing
5243
** SQL function or aggregate, pass NULL pointers for all three function
5244
** callbacks.
5245
**
5246
** ^The sixth, seventh, eighth and ninth parameters (xStep, xFinal, xValue
5247
** and xInverse) passed to sqlite3_create_window_function are pointers to
5248
** C-language callbacks that implement the new function. xStep and xFinal
5249
** must both be non-NULL. xValue and xInverse may either both be NULL, in
5250
** which case a regular aggregate function is created, or must both be
5251
** non-NULL, in which case the new function may be used as either an aggregate
5252
** or aggregate window function. More details regarding the implementation
5253
** of aggregate window functions are
5254
** [user-defined window functions|available here].
5255
**
5256
** ^(If the final parameter to sqlite3_create_function_v2() or
5257
** sqlite3_create_window_function() is not NULL, then it is destructor for
5258
** the application data pointer. The destructor is invoked when the function
5259
** is deleted, either by being overloaded or when the database connection
5260
** closes.)^ ^The destructor is also invoked if the call to
5261
** sqlite3_create_function_v2() fails.  ^When the destructor callback is
5262
** invoked, it is passed a single argument which is a copy of the application
5263
** data pointer which was the fifth parameter to sqlite3_create_function_v2().
5264
**
5265
** ^It is permitted to register multiple implementations of the same
5266
** functions with the same name but with either differing numbers of
5267
** arguments or differing preferred text encodings.  ^SQLite will use
5268
** the implementation that most closely matches the way in which the
5269
** SQL function is used.  ^A function implementation with a non-negative
5270
** nArg parameter is a better match than a function implementation with
5271
** a negative nArg.  ^A function where the preferred text encoding
5272
** matches the database encoding is a better
5273
** match than a function where the encoding is different.
5274
** ^A function where the encoding difference is between UTF16le and UTF16be
5275
** is a closer match than a function where the encoding difference is
5276
** between UTF8 and UTF16.
5277
**
5278
** ^Built-in functions may be overloaded by new application-defined functions.
5279
**
5280
** ^An application-defined function is permitted to call other
5281
** SQLite interfaces.  However, such calls must not
5282
** close the database connection nor finalize or reset the prepared
5283
** statement in which the function is running.
5284
*/
5285
SQLITE_API int sqlite3_create_function(
5286
  sqlite3 *db,
5287
  const char *zFunctionName,
5288
  int nArg,
5289
  int eTextRep,
5290
  void *pApp,
5291
  void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
5292
  void (*xStep)(sqlite3_context*,int,sqlite3_value**),
5293
  void (*xFinal)(sqlite3_context*)
5294
);
5295
SQLITE_API int sqlite3_create_function16(
5296
  sqlite3 *db,
5297
  const void *zFunctionName,
5298
  int nArg,
5299
  int eTextRep,
5300
  void *pApp,
5301
  void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
5302
  void (*xStep)(sqlite3_context*,int,sqlite3_value**),
5303
  void (*xFinal)(sqlite3_context*)
5304
);
5305
SQLITE_API int sqlite3_create_function_v2(
5306
  sqlite3 *db,
5307
  const char *zFunctionName,
5308
  int nArg,
5309
  int eTextRep,
5310
  void *pApp,
5311
  void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
5312
  void (*xStep)(sqlite3_context*,int,sqlite3_value**),
5313
  void (*xFinal)(sqlite3_context*),
5314
  void(*xDestroy)(void*)
5315
);
5316
SQLITE_API int sqlite3_create_window_function(
5317
  sqlite3 *db,
5318
  const char *zFunctionName,
5319
  int nArg,
5320
  int eTextRep,
5321
  void *pApp,
5322
  void (*xStep)(sqlite3_context*,int,sqlite3_value**),
5323
  void (*xFinal)(sqlite3_context*),
5324
  void (*xValue)(sqlite3_context*),
5325
  void (*xInverse)(sqlite3_context*,int,sqlite3_value**),
5326
  void(*xDestroy)(void*)
5327
);
5328
5329
/*
5330
** CAPI3REF: Text Encodings
5331
**
5332
** These constant define integer codes that represent the various
5333
** text encodings supported by SQLite.
5334
*/
5335
740
#define SQLITE_UTF8           1    /* IMP: R-37514-35566 */
5336
#define SQLITE_UTF16LE        2    /* IMP: R-03371-37637 */
5337
#define SQLITE_UTF16BE        3    /* IMP: R-51971-34154 */
5338
#define SQLITE_UTF16          4    /* Use native byte order */
5339
#define SQLITE_ANY            5    /* Deprecated */
5340
#define SQLITE_UTF16_ALIGNED  8    /* sqlite3_create_collation only */
5341
5342
/*
5343
** CAPI3REF: Function Flags
5344
**
5345
** These constants may be ORed together with the
5346
** [SQLITE_UTF8 | preferred text encoding] as the fourth argument
5347
** to [sqlite3_create_function()], [sqlite3_create_function16()], or
5348
** [sqlite3_create_function_v2()].
5349
**
5350
** <dl>
5351
** [[SQLITE_DETERMINISTIC]] <dt>SQLITE_DETERMINISTIC</dt><dd>
5352
** The SQLITE_DETERMINISTIC flag means that the new function always gives
5353
** the same output when the input parameters are the same.
5354
** The [abs|abs() function] is deterministic, for example, but
5355
** [randomblob|randomblob()] is not.  Functions must
5356
** be deterministic in order to be used in certain contexts such as
5357
** with the WHERE clause of [partial indexes] or in [generated columns].
5358
** SQLite might also optimize deterministic functions by factoring them
5359
** out of inner loops.
5360
** </dd>
5361
**
5362
** [[SQLITE_DIRECTONLY]] <dt>SQLITE_DIRECTONLY</dt><dd>
5363
** The SQLITE_DIRECTONLY flag means that the function may only be invoked
5364
** from top-level SQL, and cannot be used in VIEWs or TRIGGERs nor in
5365
** schema structures such as [CHECK constraints], [DEFAULT clauses],
5366
** [expression indexes], [partial indexes], or [generated columns].
5367
** The SQLITE_DIRECTONLY flags is a security feature which is recommended
5368
** for all [application-defined SQL functions], and especially for functions
5369
** that have side-effects or that could potentially leak sensitive
5370
** information.
5371
** </dd>
5372
**
5373
** [[SQLITE_INNOCUOUS]] <dt>SQLITE_INNOCUOUS</dt><dd>
5374
** The SQLITE_INNOCUOUS flag means that the function is unlikely
5375
** to cause problems even if misused.  An innocuous function should have
5376
** no side effects and should not depend on any values other than its
5377
** input parameters. The [abs|abs() function] is an example of an
5378
** innocuous function.
5379
** The [load_extension() SQL function] is not innocuous because of its
5380
** side effects.
5381
** <p> SQLITE_INNOCUOUS is similar to SQLITE_DETERMINISTIC, but is not
5382
** exactly the same.  The [random|random() function] is an example of a
5383
** function that is innocuous but not deterministic.
5384
** <p>Some heightened security settings
5385
** ([SQLITE_DBCONFIG_TRUSTED_SCHEMA] and [PRAGMA trusted_schema=OFF])
5386
** disable the use of SQL functions inside views and triggers and in
5387
** schema structures such as [CHECK constraints], [DEFAULT clauses],
5388
** [expression indexes], [partial indexes], and [generated columns] unless
5389
** the function is tagged with SQLITE_INNOCUOUS.  Most built-in functions
5390
** are innocuous.  Developers are advised to avoid using the
5391
** SQLITE_INNOCUOUS flag for application-defined functions unless the
5392
** function has been carefully audited and found to be free of potentially
5393
** security-adverse side-effects and information-leaks.
5394
** </dd>
5395
**
5396
** [[SQLITE_SUBTYPE]] <dt>SQLITE_SUBTYPE</dt><dd>
5397
** The SQLITE_SUBTYPE flag indicates to SQLite that a function may call
5398
** [sqlite3_value_subtype()] to inspect the sub-types of its arguments.
5399
** Specifying this flag makes no difference for scalar or aggregate user
5400
** functions. However, if it is not specified for a user-defined window
5401
** function, then any sub-types belonging to arguments passed to the window
5402
** function may be discarded before the window function is called (i.e.
5403
** sqlite3_value_subtype() will always return 0).
5404
** </dd>
5405
** </dl>
5406
*/
5407
1
#define SQLITE_DETERMINISTIC    0x000000800
5408
#define SQLITE_DIRECTONLY       0x000080000
5409
#define SQLITE_SUBTYPE          0x000100000
5410
#define SQLITE_INNOCUOUS        0x000200000
5411
5412
/*
5413
** CAPI3REF: Deprecated Functions
5414
** DEPRECATED
5415
**
5416
** These functions are [deprecated].  In order to maintain
5417
** backwards compatibility with older code, these functions continue
5418
** to be supported.  However, new applications should avoid
5419
** the use of these functions.  To encourage programmers to avoid
5420
** these functions, we will not explain what they do.
5421
*/
5422
#ifndef SQLITE_OMIT_DEPRECATED
5423
SQLITE_API SQLITE_DEPRECATED int sqlite3_aggregate_count(sqlite3_context*);
5424
SQLITE_API SQLITE_DEPRECATED int sqlite3_expired(sqlite3_stmt*);
5425
SQLITE_API SQLITE_DEPRECATED int sqlite3_transfer_bindings(sqlite3_stmt*, sqlite3_stmt*);
5426
SQLITE_API SQLITE_DEPRECATED int sqlite3_global_recover(void);
5427
SQLITE_API SQLITE_DEPRECATED void sqlite3_thread_cleanup(void);
5428
SQLITE_API SQLITE_DEPRECATED int sqlite3_memory_alarm(void(*)(void*,sqlite3_int64,int),
5429
                      void*,sqlite3_int64);
5430
#endif
5431
5432
/*
5433
** CAPI3REF: Obtaining SQL Values
5434
** METHOD: sqlite3_value
5435
**
5436
** <b>Summary:</b>
5437
** <blockquote><table border=0 cellpadding=0 cellspacing=0>
5438
** <tr><td><b>sqlite3_value_blob</b><td>&rarr;<td>BLOB value
5439
** <tr><td><b>sqlite3_value_double</b><td>&rarr;<td>REAL value
5440
** <tr><td><b>sqlite3_value_int</b><td>&rarr;<td>32-bit INTEGER value
5441
** <tr><td><b>sqlite3_value_int64</b><td>&rarr;<td>64-bit INTEGER value
5442
** <tr><td><b>sqlite3_value_pointer</b><td>&rarr;<td>Pointer value
5443
** <tr><td><b>sqlite3_value_text</b><td>&rarr;<td>UTF-8 TEXT value
5444
** <tr><td><b>sqlite3_value_text16</b><td>&rarr;<td>UTF-16 TEXT value in
5445
** the native byteorder
5446
** <tr><td><b>sqlite3_value_text16be</b><td>&rarr;<td>UTF-16be TEXT value
5447
** <tr><td><b>sqlite3_value_text16le</b><td>&rarr;<td>UTF-16le TEXT value
5448
** <tr><td>&nbsp;<td>&nbsp;<td>&nbsp;
5449
** <tr><td><b>sqlite3_value_bytes</b><td>&rarr;<td>Size of a BLOB
5450
** or a UTF-8 TEXT in bytes
5451
** <tr><td><b>sqlite3_value_bytes16&nbsp;&nbsp;</b>
5452
** <td>&rarr;&nbsp;&nbsp;<td>Size of UTF-16
5453
** TEXT in bytes
5454
** <tr><td><b>sqlite3_value_type</b><td>&rarr;<td>Default
5455
** datatype of the value
5456
** <tr><td><b>sqlite3_value_numeric_type&nbsp;&nbsp;</b>
5457
** <td>&rarr;&nbsp;&nbsp;<td>Best numeric datatype of the value
5458
** <tr><td><b>sqlite3_value_nochange&nbsp;&nbsp;</b>
5459
** <td>&rarr;&nbsp;&nbsp;<td>True if the column is unchanged in an UPDATE
5460
** against a virtual table.
5461
** <tr><td><b>sqlite3_value_frombind&nbsp;&nbsp;</b>
5462
** <td>&rarr;&nbsp;&nbsp;<td>True if value originated from a [bound parameter]
5463
** </table></blockquote>
5464
**
5465
** <b>Details:</b>
5466
**
5467
** These routines extract type, size, and content information from
5468
** [protected sqlite3_value] objects.  Protected sqlite3_value objects
5469
** are used to pass parameter information into the functions that
5470
** implement [application-defined SQL functions] and [virtual tables].
5471
**
5472
** These routines work only with [protected sqlite3_value] objects.
5473
** Any attempt to use these routines on an [unprotected sqlite3_value]
5474
** is not threadsafe.
5475
**
5476
** ^These routines work just like the corresponding [column access functions]
5477
** except that these routines take a single [protected sqlite3_value] object
5478
** pointer instead of a [sqlite3_stmt*] pointer and an integer column number.
5479
**
5480
** ^The sqlite3_value_text16() interface extracts a UTF-16 string
5481
** in the native byte-order of the host machine.  ^The
5482
** sqlite3_value_text16be() and sqlite3_value_text16le() interfaces
5483
** extract UTF-16 strings as big-endian and little-endian respectively.
5484
**
5485
** ^If [sqlite3_value] object V was initialized
5486
** using [sqlite3_bind_pointer(S,I,P,X,D)] or [sqlite3_result_pointer(C,P,X,D)]
5487
** and if X and Y are strings that compare equal according to strcmp(X,Y),
5488
** then sqlite3_value_pointer(V,Y) will return the pointer P.  ^Otherwise,
5489
** sqlite3_value_pointer(V,Y) returns a NULL. The sqlite3_bind_pointer()
5490
** routine is part of the [pointer passing interface] added for SQLite 3.20.0.
5491
**
5492
** ^(The sqlite3_value_type(V) interface returns the
5493
** [SQLITE_INTEGER | datatype code] for the initial datatype of the
5494
** [sqlite3_value] object V. The returned value is one of [SQLITE_INTEGER],
5495
** [SQLITE_FLOAT], [SQLITE_TEXT], [SQLITE_BLOB], or [SQLITE_NULL].)^
5496
** Other interfaces might change the datatype for an sqlite3_value object.
5497
** For example, if the datatype is initially SQLITE_INTEGER and
5498
** sqlite3_value_text(V) is called to extract a text value for that
5499
** integer, then subsequent calls to sqlite3_value_type(V) might return
5500
** SQLITE_TEXT.  Whether or not a persistent internal datatype conversion
5501
** occurs is undefined and may change from one release of SQLite to the next.
5502
**
5503
** ^(The sqlite3_value_numeric_type() interface attempts to apply
5504
** numeric affinity to the value.  This means that an attempt is
5505
** made to convert the value to an integer or floating point.  If
5506
** such a conversion is possible without loss of information (in other
5507
** words, if the value is a string that looks like a number)
5508
** then the conversion is performed.  Otherwise no conversion occurs.
5509
** The [SQLITE_INTEGER | datatype] after conversion is returned.)^
5510
**
5511
** ^Within the [xUpdate] method of a [virtual table], the
5512
** sqlite3_value_nochange(X) interface returns true if and only if
5513
** the column corresponding to X is unchanged by the UPDATE operation
5514
** that the xUpdate method call was invoked to implement and if
5515
** and the prior [xColumn] method call that was invoked to extracted
5516
** the value for that column returned without setting a result (probably
5517
** because it queried [sqlite3_vtab_nochange()] and found that the column
5518
** was unchanging).  ^Within an [xUpdate] method, any value for which
5519
** sqlite3_value_nochange(X) is true will in all other respects appear
5520
** to be a NULL value.  If sqlite3_value_nochange(X) is invoked anywhere other
5521
** than within an [xUpdate] method call for an UPDATE statement, then
5522
** the return value is arbitrary and meaningless.
5523
**
5524
** ^The sqlite3_value_frombind(X) interface returns non-zero if the
5525
** value X originated from one of the [sqlite3_bind_int|sqlite3_bind()]
5526
** interfaces.  ^If X comes from an SQL literal value, or a table column,
5527
** or an expression, then sqlite3_value_frombind(X) returns zero.
5528
**
5529
** Please pay particular attention to the fact that the pointer returned
5530
** from [sqlite3_value_blob()], [sqlite3_value_text()], or
5531
** [sqlite3_value_text16()] can be invalidated by a subsequent call to
5532
** [sqlite3_value_bytes()], [sqlite3_value_bytes16()], [sqlite3_value_text()],
5533
** or [sqlite3_value_text16()].
5534
**
5535
** These routines must be called from the same thread as
5536
** the SQL function that supplied the [sqlite3_value*] parameters.
5537
**
5538
** As long as the input parameter is correct, these routines can only
5539
** fail if an out-of-memory error occurs during a format conversion.
5540
** Only the following subset of interfaces are subject to out-of-memory
5541
** errors:
5542
**
5543
** <ul>
5544
** <li> sqlite3_value_blob()
5545
** <li> sqlite3_value_text()
5546
** <li> sqlite3_value_text16()
5547
** <li> sqlite3_value_text16le()
5548
** <li> sqlite3_value_text16be()
5549
** <li> sqlite3_value_bytes()
5550
** <li> sqlite3_value_bytes16()
5551
** </ul>
5552
**
5553
** If an out-of-memory error occurs, then the return value from these
5554
** routines is the same as if the column had contained an SQL NULL value.
5555
** Valid SQL NULL returns can be distinguished from out-of-memory errors
5556
** by invoking the [sqlite3_errcode()] immediately after the suspect
5557
** return value is obtained and before any
5558
** other SQLite interface is called on the same [database connection].
5559
*/
5560
SQLITE_API const void *sqlite3_value_blob(sqlite3_value*);
5561
SQLITE_API double sqlite3_value_double(sqlite3_value*);
5562
SQLITE_API int sqlite3_value_int(sqlite3_value*);
5563
SQLITE_API sqlite3_int64 sqlite3_value_int64(sqlite3_value*);
5564
SQLITE_API void *sqlite3_value_pointer(sqlite3_value*, const char*);
5565
SQLITE_API const unsigned char *sqlite3_value_text(sqlite3_value*);
5566
SQLITE_API const void *sqlite3_value_text16(sqlite3_value*);
5567
SQLITE_API const void *sqlite3_value_text16le(sqlite3_value*);
5568
SQLITE_API const void *sqlite3_value_text16be(sqlite3_value*);
5569
SQLITE_API int sqlite3_value_bytes(sqlite3_value*);
5570
SQLITE_API int sqlite3_value_bytes16(sqlite3_value*);
5571
SQLITE_API int sqlite3_value_type(sqlite3_value*);
5572
SQLITE_API int sqlite3_value_numeric_type(sqlite3_value*);
5573
SQLITE_API int sqlite3_value_nochange(sqlite3_value*);
5574
SQLITE_API int sqlite3_value_frombind(sqlite3_value*);
5575
5576
/*
5577
** CAPI3REF: Finding The Subtype Of SQL Values
5578
** METHOD: sqlite3_value
5579
**
5580
** The sqlite3_value_subtype(V) function returns the subtype for
5581
** an [application-defined SQL function] argument V.  The subtype
5582
** information can be used to pass a limited amount of context from
5583
** one SQL function to another.  Use the [sqlite3_result_subtype()]
5584
** routine to set the subtype for the return value of an SQL function.
5585
*/
5586
SQLITE_API unsigned int sqlite3_value_subtype(sqlite3_value*);
5587
5588
/*
5589
** CAPI3REF: Copy And Free SQL Values
5590
** METHOD: sqlite3_value
5591
**
5592
** ^The sqlite3_value_dup(V) interface makes a copy of the [sqlite3_value]
5593
** object D and returns a pointer to that copy.  ^The [sqlite3_value] returned
5594
** is a [protected sqlite3_value] object even if the input is not.
5595
** ^The sqlite3_value_dup(V) interface returns NULL if V is NULL or if a
5596
** memory allocation fails. ^If V is a [pointer value], then the result
5597
** of sqlite3_value_dup(V) is a NULL value.
5598
**
5599
** ^The sqlite3_value_free(V) interface frees an [sqlite3_value] object
5600
** previously obtained from [sqlite3_value_dup()].  ^If V is a NULL pointer
5601
** then sqlite3_value_free(V) is a harmless no-op.
5602
*/
5603
SQLITE_API sqlite3_value *sqlite3_value_dup(const sqlite3_value*);
5604
SQLITE_API void sqlite3_value_free(sqlite3_value*);
5605
5606
/*
5607
** CAPI3REF: Obtain Aggregate Function Context
5608
** METHOD: sqlite3_context
5609
**
5610
** Implementations of aggregate SQL functions use this
5611
** routine to allocate memory for storing their state.
5612
**
5613
** ^The first time the sqlite3_aggregate_context(C,N) routine is called
5614
** for a particular aggregate function, SQLite allocates
5615
** N bytes of memory, zeroes out that memory, and returns a pointer
5616
** to the new memory. ^On second and subsequent calls to
5617
** sqlite3_aggregate_context() for the same aggregate function instance,
5618
** the same buffer is returned.  Sqlite3_aggregate_context() is normally
5619
** called once for each invocation of the xStep callback and then one
5620
** last time when the xFinal callback is invoked.  ^(When no rows match
5621
** an aggregate query, the xStep() callback of the aggregate function
5622
** implementation is never called and xFinal() is called exactly once.
5623
** In those cases, sqlite3_aggregate_context() might be called for the
5624
** first time from within xFinal().)^
5625
**
5626
** ^The sqlite3_aggregate_context(C,N) routine returns a NULL pointer
5627
** when first called if N is less than or equal to zero or if a memory
5628
** allocate error occurs.
5629
**
5630
** ^(The amount of space allocated by sqlite3_aggregate_context(C,N) is
5631
** determined by the N parameter on first successful call.  Changing the
5632
** value of N in any subsequent call to sqlite3_aggregate_context() within
5633
** the same aggregate function instance will not resize the memory
5634
** allocation.)^  Within the xFinal callback, it is customary to set
5635
** N=0 in calls to sqlite3_aggregate_context(C,N) so that no
5636
** pointless memory allocations occur.
5637
**
5638
** ^SQLite automatically frees the memory allocated by
5639
** sqlite3_aggregate_context() when the aggregate query concludes.
5640
**
5641
** The first parameter must be a copy of the
5642
** [sqlite3_context | SQL function context] that is the first parameter
5643
** to the xStep or xFinal callback routine that implements the aggregate
5644
** function.
5645
**
5646
** This routine must be called from the same thread in which
5647
** the aggregate SQL function is running.
5648
*/
5649
SQLITE_API void *sqlite3_aggregate_context(sqlite3_context*, int nBytes);
5650
5651
/*
5652
** CAPI3REF: User Data For Functions
5653
** METHOD: sqlite3_context
5654
**
5655
** ^The sqlite3_user_data() interface returns a copy of
5656
** the pointer that was the pUserData parameter (the 5th parameter)
5657
** of the [sqlite3_create_function()]
5658
** and [sqlite3_create_function16()] routines that originally
5659
** registered the application defined function.
5660
**
5661
** This routine must be called from the same thread in which
5662
** the application-defined function is running.
5663
*/
5664
SQLITE_API void *sqlite3_user_data(sqlite3_context*);
5665
5666
/*
5667
** CAPI3REF: Database Connection For Functions
5668
** METHOD: sqlite3_context
5669
**
5670
** ^The sqlite3_context_db_handle() interface returns a copy of
5671
** the pointer to the [database connection] (the 1st parameter)
5672
** of the [sqlite3_create_function()]
5673
** and [sqlite3_create_function16()] routines that originally
5674
** registered the application defined function.
5675
*/
5676
SQLITE_API sqlite3 *sqlite3_context_db_handle(sqlite3_context*);
5677
5678
/*
5679
** CAPI3REF: Function Auxiliary Data
5680
** METHOD: sqlite3_context
5681
**
5682
** These functions may be used by (non-aggregate) SQL functions to
5683
** associate metadata with argument values. If the same value is passed to
5684
** multiple invocations of the same SQL function during query execution, under
5685
** some circumstances the associated metadata may be preserved.  An example
5686
** of where this might be useful is in a regular-expression matching
5687
** function. The compiled version of the regular expression can be stored as
5688
** metadata associated with the pattern string.
5689
** Then as long as the pattern string remains the same,
5690
** the compiled regular expression can be reused on multiple
5691
** invocations of the same function.
5692
**
5693
** ^The sqlite3_get_auxdata(C,N) interface returns a pointer to the metadata
5694
** associated by the sqlite3_set_auxdata(C,N,P,X) function with the Nth argument
5695
** value to the application-defined function.  ^N is zero for the left-most
5696
** function argument.  ^If there is no metadata
5697
** associated with the function argument, the sqlite3_get_auxdata(C,N) interface
5698
** returns a NULL pointer.
5699
**
5700
** ^The sqlite3_set_auxdata(C,N,P,X) interface saves P as metadata for the N-th
5701
** argument of the application-defined function.  ^Subsequent
5702
** calls to sqlite3_get_auxdata(C,N) return P from the most recent
5703
** sqlite3_set_auxdata(C,N,P,X) call if the metadata is still valid or
5704
** NULL if the metadata has been discarded.
5705
** ^After each call to sqlite3_set_auxdata(C,N,P,X) where X is not NULL,
5706
** SQLite will invoke the destructor function X with parameter P exactly
5707
** once, when the metadata is discarded.
5708
** SQLite is free to discard the metadata at any time, including: <ul>
5709
** <li> ^(when the corresponding function parameter changes)^, or
5710
** <li> ^(when [sqlite3_reset()] or [sqlite3_finalize()] is called for the
5711
**      SQL statement)^, or
5712
** <li> ^(when sqlite3_set_auxdata() is invoked again on the same
5713
**       parameter)^, or
5714
** <li> ^(during the original sqlite3_set_auxdata() call when a memory
5715
**      allocation error occurs.)^ </ul>
5716
**
5717
** Note the last bullet in particular.  The destructor X in
5718
** sqlite3_set_auxdata(C,N,P,X) might be called immediately, before the
5719
** sqlite3_set_auxdata() interface even returns.  Hence sqlite3_set_auxdata()
5720
** should be called near the end of the function implementation and the
5721
** function implementation should not make any use of P after
5722
** sqlite3_set_auxdata() has been called.
5723
**
5724
** ^(In practice, metadata is preserved between function calls for
5725
** function parameters that are compile-time constants, including literal
5726
** values and [parameters] and expressions composed from the same.)^
5727
**
5728
** The value of the N parameter to these interfaces should be non-negative.
5729
** Future enhancements may make use of negative N values to define new
5730
** kinds of function caching behavior.
5731
**
5732
** These routines must be called from the same thread in which
5733
** the SQL function is running.
5734
*/
5735
SQLITE_API void *sqlite3_get_auxdata(sqlite3_context*, int N);
5736
SQLITE_API void sqlite3_set_auxdata(sqlite3_context*, int N, void*, void (*)(void*));
5737
5738
5739
/*
5740
** CAPI3REF: Constants Defining Special Destructor Behavior
5741
**
5742
** These are special values for the destructor that is passed in as the
5743
** final argument to routines like [sqlite3_result_blob()].  ^If the destructor
5744
** argument is SQLITE_STATIC, it means that the content pointer is constant
5745
** and will never change.  It does not need to be destroyed.  ^The
5746
** SQLITE_TRANSIENT value means that the content will likely change in
5747
** the near future and that SQLite should make its own private copy of
5748
** the content before returning.
5749
**
5750
** The typedef is necessary to work around problems in certain
5751
** C++ compilers.
5752
*/
5753
typedef void (*sqlite3_destructor_type)(void*);
5754
#define SQLITE_STATIC      ((sqlite3_destructor_type)0)
5755
275
#define SQLITE_TRANSIENT   ((sqlite3_destructor_type)-1)
5756
5757
/*
5758
** CAPI3REF: Setting The Result Of An SQL Function
5759
** METHOD: sqlite3_context
5760
**
5761
** These routines are used by the xFunc or xFinal callbacks that
5762
** implement SQL functions and aggregates.  See
5763
** [sqlite3_create_function()] and [sqlite3_create_function16()]
5764
** for additional information.
5765
**
5766
** These functions work very much like the [parameter binding] family of
5767
** functions used to bind values to host parameters in prepared statements.
5768
** Refer to the [SQL parameter] documentation for additional information.
5769
**
5770
** ^The sqlite3_result_blob() interface sets the result from
5771
** an application-defined function to be the BLOB whose content is pointed
5772
** to by the second parameter and which is N bytes long where N is the
5773
** third parameter.
5774
**
5775
** ^The sqlite3_result_zeroblob(C,N) and sqlite3_result_zeroblob64(C,N)
5776
** interfaces set the result of the application-defined function to be
5777
** a BLOB containing all zero bytes and N bytes in size.
5778
**
5779
** ^The sqlite3_result_double() interface sets the result from
5780
** an application-defined function to be a floating point value specified
5781
** by its 2nd argument.
5782
**
5783
** ^The sqlite3_result_error() and sqlite3_result_error16() functions
5784
** cause the implemented SQL function to throw an exception.
5785
** ^SQLite uses the string pointed to by the
5786
** 2nd parameter of sqlite3_result_error() or sqlite3_result_error16()
5787
** as the text of an error message.  ^SQLite interprets the error
5788
** message string from sqlite3_result_error() as UTF-8. ^SQLite
5789
** interprets the string from sqlite3_result_error16() as UTF-16 using
5790
** the same [byte-order determination rules] as [sqlite3_bind_text16()].
5791
** ^If the third parameter to sqlite3_result_error()
5792
** or sqlite3_result_error16() is negative then SQLite takes as the error
5793
** message all text up through the first zero character.
5794
** ^If the third parameter to sqlite3_result_error() or
5795
** sqlite3_result_error16() is non-negative then SQLite takes that many
5796
** bytes (not characters) from the 2nd parameter as the error message.
5797
** ^The sqlite3_result_error() and sqlite3_result_error16()
5798
** routines make a private copy of the error message text before
5799
** they return.  Hence, the calling function can deallocate or
5800
** modify the text after they return without harm.
5801
** ^The sqlite3_result_error_code() function changes the error code
5802
** returned by SQLite as a result of an error in a function.  ^By default,
5803
** the error code is SQLITE_ERROR.  ^A subsequent call to sqlite3_result_error()
5804
** or sqlite3_result_error16() resets the error code to SQLITE_ERROR.
5805
**
5806
** ^The sqlite3_result_error_toobig() interface causes SQLite to throw an
5807
** error indicating that a string or BLOB is too long to represent.
5808
**
5809
** ^The sqlite3_result_error_nomem() interface causes SQLite to throw an
5810
** error indicating that a memory allocation failed.
5811
**
5812
** ^The sqlite3_result_int() interface sets the return value
5813
** of the application-defined function to be the 32-bit signed integer
5814
** value given in the 2nd argument.
5815
** ^The sqlite3_result_int64() interface sets the return value
5816
** of the application-defined function to be the 64-bit signed integer
5817
** value given in the 2nd argument.
5818
**
5819
** ^The sqlite3_result_null() interface sets the return value
5820
** of the application-defined function to be NULL.
5821
**
5822
** ^The sqlite3_result_text(), sqlite3_result_text16(),
5823
** sqlite3_result_text16le(), and sqlite3_result_text16be() interfaces
5824
** set the return value of the application-defined function to be
5825
** a text string which is represented as UTF-8, UTF-16 native byte order,
5826
** UTF-16 little endian, or UTF-16 big endian, respectively.
5827
** ^The sqlite3_result_text64() interface sets the return value of an
5828
** application-defined function to be a text string in an encoding
5829
** specified by the fifth (and last) parameter, which must be one
5830
** of [SQLITE_UTF8], [SQLITE_UTF16], [SQLITE_UTF16BE], or [SQLITE_UTF16LE].
5831
** ^SQLite takes the text result from the application from
5832
** the 2nd parameter of the sqlite3_result_text* interfaces.
5833
** ^If the 3rd parameter to the sqlite3_result_text* interfaces
5834
** is negative, then SQLite takes result text from the 2nd parameter
5835
** through the first zero character.
5836
** ^If the 3rd parameter to the sqlite3_result_text* interfaces
5837
** is non-negative, then as many bytes (not characters) of the text
5838
** pointed to by the 2nd parameter are taken as the application-defined
5839
** function result.  If the 3rd parameter is non-negative, then it
5840
** must be the byte offset into the string where the NUL terminator would
5841
** appear if the string where NUL terminated.  If any NUL characters occur
5842
** in the string at a byte offset that is less than the value of the 3rd
5843
** parameter, then the resulting string will contain embedded NULs and the
5844
** result of expressions operating on strings with embedded NULs is undefined.
5845
** ^If the 4th parameter to the sqlite3_result_text* interfaces
5846
** or sqlite3_result_blob is a non-NULL pointer, then SQLite calls that
5847
** function as the destructor on the text or BLOB result when it has
5848
** finished using that result.
5849
** ^If the 4th parameter to the sqlite3_result_text* interfaces or to
5850
** sqlite3_result_blob is the special constant SQLITE_STATIC, then SQLite
5851
** assumes that the text or BLOB result is in constant space and does not
5852
** copy the content of the parameter nor call a destructor on the content
5853
** when it has finished using that result.
5854
** ^If the 4th parameter to the sqlite3_result_text* interfaces
5855
** or sqlite3_result_blob is the special constant SQLITE_TRANSIENT
5856
** then SQLite makes a copy of the result into space obtained
5857
** from [sqlite3_malloc()] before it returns.
5858
**
5859
** ^For the sqlite3_result_text16(), sqlite3_result_text16le(), and
5860
** sqlite3_result_text16be() routines, and for sqlite3_result_text64()
5861
** when the encoding is not UTF8, if the input UTF16 begins with a
5862
** byte-order mark (BOM, U+FEFF) then the BOM is removed from the
5863
** string and the rest of the string is interpreted according to the
5864
** byte-order specified by the BOM.  ^The byte-order specified by
5865
** the BOM at the beginning of the text overrides the byte-order
5866
** specified by the interface procedure.  ^So, for example, if
5867
** sqlite3_result_text16le() is invoked with text that begins
5868
** with bytes 0xfe, 0xff (a big-endian byte-order mark) then the
5869
** first two bytes of input are skipped and the remaining input
5870
** is interpreted as UTF16BE text.
5871
**
5872
** ^For UTF16 input text to the sqlite3_result_text16(),
5873
** sqlite3_result_text16be(), sqlite3_result_text16le(), and
5874
** sqlite3_result_text64() routines, if the text contains invalid
5875
** UTF16 characters, the invalid characters might be converted
5876
** into the unicode replacement character, U+FFFD.
5877
**
5878
** ^The sqlite3_result_value() interface sets the result of
5879
** the application-defined function to be a copy of the
5880
** [unprotected sqlite3_value] object specified by the 2nd parameter.  ^The
5881
** sqlite3_result_value() interface makes a copy of the [sqlite3_value]
5882
** so that the [sqlite3_value] specified in the parameter may change or
5883
** be deallocated after sqlite3_result_value() returns without harm.
5884
** ^A [protected sqlite3_value] object may always be used where an
5885
** [unprotected sqlite3_value] object is required, so either
5886
** kind of [sqlite3_value] object can be used with this interface.
5887
**
5888
** ^The sqlite3_result_pointer(C,P,T,D) interface sets the result to an
5889
** SQL NULL value, just like [sqlite3_result_null(C)], except that it
5890
** also associates the host-language pointer P or type T with that
5891
** NULL value such that the pointer can be retrieved within an
5892
** [application-defined SQL function] using [sqlite3_value_pointer()].
5893
** ^If the D parameter is not NULL, then it is a pointer to a destructor
5894
** for the P parameter.  ^SQLite invokes D with P as its only argument
5895
** when SQLite is finished with P.  The T parameter should be a static
5896
** string and preferably a string literal. The sqlite3_result_pointer()
5897
** routine is part of the [pointer passing interface] added for SQLite 3.20.0.
5898
**
5899
** If these routines are called from within the different thread
5900
** than the one containing the application-defined function that received
5901
** the [sqlite3_context] pointer, the results are undefined.
5902
*/
5903
SQLITE_API void sqlite3_result_blob(sqlite3_context*, const void*, int, void(*)(void*));
5904
SQLITE_API void sqlite3_result_blob64(sqlite3_context*,const void*,
5905
                           sqlite3_uint64,void(*)(void*));
5906
SQLITE_API void sqlite3_result_double(sqlite3_context*, double);
5907
SQLITE_API void sqlite3_result_error(sqlite3_context*, const char*, int);
5908
SQLITE_API void sqlite3_result_error16(sqlite3_context*, const void*, int);
5909
SQLITE_API void sqlite3_result_error_toobig(sqlite3_context*);
5910
SQLITE_API void sqlite3_result_error_nomem(sqlite3_context*);
5911
SQLITE_API void sqlite3_result_error_code(sqlite3_context*, int);
5912
SQLITE_API void sqlite3_result_int(sqlite3_context*, int);
5913
SQLITE_API void sqlite3_result_int64(sqlite3_context*, sqlite3_int64);
5914
SQLITE_API void sqlite3_result_null(sqlite3_context*);
5915
SQLITE_API void sqlite3_result_text(sqlite3_context*, const char*, int, void(*)(void*));
5916
SQLITE_API void sqlite3_result_text64(sqlite3_context*, const char*,sqlite3_uint64,
5917
                           void(*)(void*), unsigned char encoding);
5918
SQLITE_API void sqlite3_result_text16(sqlite3_context*, const void*, int, void(*)(void*));
5919
SQLITE_API void sqlite3_result_text16le(sqlite3_context*, const void*, int,void(*)(void*));
5920
SQLITE_API void sqlite3_result_text16be(sqlite3_context*, const void*, int,void(*)(void*));
5921
SQLITE_API void sqlite3_result_value(sqlite3_context*, sqlite3_value*);
5922
SQLITE_API void sqlite3_result_pointer(sqlite3_context*, void*,const char*,void(*)(void*));
5923
SQLITE_API void sqlite3_result_zeroblob(sqlite3_context*, int n);
5924
SQLITE_API int sqlite3_result_zeroblob64(sqlite3_context*, sqlite3_uint64 n);
5925
5926
5927
/*
5928
** CAPI3REF: Setting The Subtype Of An SQL Function
5929
** METHOD: sqlite3_context
5930
**
5931
** The sqlite3_result_subtype(C,T) function causes the subtype of
5932
** the result from the [application-defined SQL function] with
5933
** [sqlite3_context] C to be the value T.  Only the lower 8 bits
5934
** of the subtype T are preserved in current versions of SQLite;
5935
** higher order bits are discarded.
5936
** The number of subtype bytes preserved by SQLite might increase
5937
** in future releases of SQLite.
5938
*/
5939
SQLITE_API void sqlite3_result_subtype(sqlite3_context*,unsigned int);
5940
5941
/*
5942
** CAPI3REF: Define New Collating Sequences
5943
** METHOD: sqlite3
5944
**
5945
** ^These functions add, remove, or modify a [collation] associated
5946
** with the [database connection] specified as the first argument.
5947
**
5948
** ^The name of the collation is a UTF-8 string
5949
** for sqlite3_create_collation() and sqlite3_create_collation_v2()
5950
** and a UTF-16 string in native byte order for sqlite3_create_collation16().
5951
** ^Collation names that compare equal according to [sqlite3_strnicmp()] are
5952
** considered to be the same name.
5953
**
5954
** ^(The third argument (eTextRep) must be one of the constants:
5955
** <ul>
5956
** <li> [SQLITE_UTF8],
5957
** <li> [SQLITE_UTF16LE],
5958
** <li> [SQLITE_UTF16BE],
5959
** <li> [SQLITE_UTF16], or
5960
** <li> [SQLITE_UTF16_ALIGNED].
5961
** </ul>)^
5962
** ^The eTextRep argument determines the encoding of strings passed
5963
** to the collating function callback, xCompare.
5964
** ^The [SQLITE_UTF16] and [SQLITE_UTF16_ALIGNED] values for eTextRep
5965
** force strings to be UTF16 with native byte order.
5966
** ^The [SQLITE_UTF16_ALIGNED] value for eTextRep forces strings to begin
5967
** on an even byte address.
5968
**
5969
** ^The fourth argument, pArg, is an application data pointer that is passed
5970
** through as the first argument to the collating function callback.
5971
**
5972
** ^The fifth argument, xCompare, is a pointer to the collating function.
5973
** ^Multiple collating functions can be registered using the same name but
5974
** with different eTextRep parameters and SQLite will use whichever
5975
** function requires the least amount of data transformation.
5976
** ^If the xCompare argument is NULL then the collating function is
5977
** deleted.  ^When all collating functions having the same name are deleted,
5978
** that collation is no longer usable.
5979
**
5980
** ^The collating function callback is invoked with a copy of the pArg
5981
** application data pointer and with two strings in the encoding specified
5982
** by the eTextRep argument.  The two integer parameters to the collating
5983
** function callback are the length of the two strings, in bytes. The collating
5984
** function must return an integer that is negative, zero, or positive
5985
** if the first string is less than, equal to, or greater than the second,
5986
** respectively.  A collating function must always return the same answer
5987
** given the same inputs.  If two or more collating functions are registered
5988
** to the same collation name (using different eTextRep values) then all
5989
** must give an equivalent answer when invoked with equivalent strings.
5990
** The collating function must obey the following properties for all
5991
** strings A, B, and C:
5992
**
5993
** <ol>
5994
** <li> If A==B then B==A.
5995
** <li> If A==B and B==C then A==C.
5996
** <li> If A&lt;B THEN B&gt;A.
5997
** <li> If A&lt;B and B&lt;C then A&lt;C.
5998
** </ol>
5999
**
6000
** If a collating function fails any of the above constraints and that
6001
** collating function is registered and used, then the behavior of SQLite
6002
** is undefined.
6003
**
6004
** ^The sqlite3_create_collation_v2() works like sqlite3_create_collation()
6005
** with the addition that the xDestroy callback is invoked on pArg when
6006
** the collating function is deleted.
6007
** ^Collating functions are deleted when they are overridden by later
6008
** calls to the collation creation functions or when the
6009
** [database connection] is closed using [sqlite3_close()].
6010
**
6011
** ^The xDestroy callback is <u>not</u> called if the
6012
** sqlite3_create_collation_v2() function fails.  Applications that invoke
6013
** sqlite3_create_collation_v2() with a non-NULL xDestroy argument should
6014
** check the return code and dispose of the application data pointer
6015
** themselves rather than expecting SQLite to deal with it for them.
6016
** This is different from every other SQLite interface.  The inconsistency
6017
** is unfortunate but cannot be changed without breaking backwards
6018
** compatibility.
6019
**
6020
** See also:  [sqlite3_collation_needed()] and [sqlite3_collation_needed16()].
6021
*/
6022
SQLITE_API int sqlite3_create_collation(
6023
  sqlite3*,
6024
  const char *zName,
6025
  int eTextRep,
6026
  void *pArg,
6027
  int(*xCompare)(void*,int,const void*,int,const void*)
6028
);
6029
SQLITE_API int sqlite3_create_collation_v2(
6030
  sqlite3*,
6031
  const char *zName,
6032
  int eTextRep,
6033
  void *pArg,
6034
  int(*xCompare)(void*,int,const void*,int,const void*),
6035
  void(*xDestroy)(void*)
6036
);
6037
SQLITE_API int sqlite3_create_collation16(
6038
  sqlite3*,
6039
  const void *zName,
6040
  int eTextRep,
6041
  void *pArg,
6042
  int(*xCompare)(void*,int,const void*,int,const void*)
6043
);
6044
6045
/*
6046
** CAPI3REF: Collation Needed Callbacks
6047
** METHOD: sqlite3
6048
**
6049
** ^To avoid having to register all collation sequences before a database
6050
** can be used, a single callback function may be registered with the
6051
** [database connection] to be invoked whenever an undefined collation
6052
** sequence is required.
6053
**
6054
** ^If the function is registered using the sqlite3_collation_needed() API,
6055
** then it is passed the names of undefined collation sequences as strings
6056
** encoded in UTF-8. ^If sqlite3_collation_needed16() is used,
6057
** the names are passed as UTF-16 in machine native byte order.
6058
** ^A call to either function replaces the existing collation-needed callback.
6059
**
6060
** ^(When the callback is invoked, the first argument passed is a copy
6061
** of the second argument to sqlite3_collation_needed() or
6062
** sqlite3_collation_needed16().  The second argument is the database
6063
** connection.  The third argument is one of [SQLITE_UTF8], [SQLITE_UTF16BE],
6064
** or [SQLITE_UTF16LE], indicating the most desirable form of the collation
6065
** sequence function required.  The fourth parameter is the name of the
6066
** required collation sequence.)^
6067
**
6068
** The callback function should register the desired collation using
6069
** [sqlite3_create_collation()], [sqlite3_create_collation16()], or
6070
** [sqlite3_create_collation_v2()].
6071
*/
6072
SQLITE_API int sqlite3_collation_needed(
6073
  sqlite3*,
6074
  void*,
6075
  void(*)(void*,sqlite3*,int eTextRep,const char*)
6076
);
6077
SQLITE_API int sqlite3_collation_needed16(
6078
  sqlite3*,
6079
  void*,
6080
  void(*)(void*,sqlite3*,int eTextRep,const void*)
6081
);
6082
6083
#ifdef SQLITE_ENABLE_CEROD
6084
/*
6085
** Specify the activation key for a CEROD database.  Unless
6086
** activated, none of the CEROD routines will work.
6087
*/
6088
SQLITE_API void sqlite3_activate_cerod(
6089
  const char *zPassPhrase        /* Activation phrase */
6090
);
6091
#endif
6092
6093
/*
6094
** CAPI3REF: Suspend Execution For A Short Time
6095
**
6096
** The sqlite3_sleep() function causes the current thread to suspend execution
6097
** for at least a number of milliseconds specified in its parameter.
6098
**
6099
** If the operating system does not support sleep requests with
6100
** millisecond time resolution, then the time will be rounded up to
6101
** the nearest second. The number of milliseconds of sleep actually
6102
** requested from the operating system is returned.
6103
**
6104
** ^SQLite implements this interface by calling the xSleep()
6105
** method of the default [sqlite3_vfs] object.  If the xSleep() method
6106
** of the default VFS is not implemented correctly, or not implemented at
6107
** all, then the behavior of sqlite3_sleep() may deviate from the description
6108
** in the previous paragraphs.
6109
*/
6110
SQLITE_API int sqlite3_sleep(int);
6111
6112
/*
6113
** CAPI3REF: Name Of The Folder Holding Temporary Files
6114
**
6115
** ^(If this global variable is made to point to a string which is
6116
** the name of a folder (a.k.a. directory), then all temporary files
6117
** created by SQLite when using a built-in [sqlite3_vfs | VFS]
6118
** will be placed in that directory.)^  ^If this variable
6119
** is a NULL pointer, then SQLite performs a search for an appropriate
6120
** temporary file directory.
6121
**
6122
** Applications are strongly discouraged from using this global variable.
6123
** It is required to set a temporary folder on Windows Runtime (WinRT).
6124
** But for all other platforms, it is highly recommended that applications
6125
** neither read nor write this variable.  This global variable is a relic
6126
** that exists for backwards compatibility of legacy applications and should
6127
** be avoided in new projects.
6128
**
6129
** It is not safe to read or modify this variable in more than one
6130
** thread at a time.  It is not safe to read or modify this variable
6131
** if a [database connection] is being used at the same time in a separate
6132
** thread.
6133
** It is intended that this variable be set once
6134
** as part of process initialization and before any SQLite interface
6135
** routines have been called and that this variable remain unchanged
6136
** thereafter.
6137
**
6138
** ^The [temp_store_directory pragma] may modify this variable and cause
6139
** it to point to memory obtained from [sqlite3_malloc].  ^Furthermore,
6140
** the [temp_store_directory pragma] always assumes that any string
6141
** that this variable points to is held in memory obtained from
6142
** [sqlite3_malloc] and the pragma may attempt to free that memory
6143
** using [sqlite3_free].
6144
** Hence, if this variable is modified directly, either it should be
6145
** made NULL or made to point to memory obtained from [sqlite3_malloc]
6146
** or else the use of the [temp_store_directory pragma] should be avoided.
6147
** Except when requested by the [temp_store_directory pragma], SQLite
6148
** does not free the memory that sqlite3_temp_directory points to.  If
6149
** the application wants that memory to be freed, it must do
6150
** so itself, taking care to only do so after all [database connection]
6151
** objects have been destroyed.
6152
**
6153
** <b>Note to Windows Runtime users:</b>  The temporary directory must be set
6154
** prior to calling [sqlite3_open] or [sqlite3_open_v2].  Otherwise, various
6155
** features that require the use of temporary files may fail.  Here is an
6156
** example of how to do this using C++ with the Windows Runtime:
6157
**
6158
** <blockquote><pre>
6159
** LPCWSTR zPath = Windows::Storage::ApplicationData::Current->
6160
** &nbsp;     TemporaryFolder->Path->Data();
6161
** char zPathBuf&#91;MAX_PATH + 1&#93;;
6162
** memset(zPathBuf, 0, sizeof(zPathBuf));
6163
** WideCharToMultiByte(CP_UTF8, 0, zPath, -1, zPathBuf, sizeof(zPathBuf),
6164
** &nbsp;     NULL, NULL);
6165
** sqlite3_temp_directory = sqlite3_mprintf("%s", zPathBuf);
6166
** </pre></blockquote>
6167
*/
6168
SQLITE_API SQLITE_EXTERN char *sqlite3_temp_directory;
6169
6170
/*
6171
** CAPI3REF: Name Of The Folder Holding Database Files
6172
**
6173
** ^(If this global variable is made to point to a string which is
6174
** the name of a folder (a.k.a. directory), then all database files
6175
** specified with a relative pathname and created or accessed by
6176
** SQLite when using a built-in windows [sqlite3_vfs | VFS] will be assumed
6177
** to be relative to that directory.)^ ^If this variable is a NULL
6178
** pointer, then SQLite assumes that all database files specified
6179
** with a relative pathname are relative to the current directory
6180
** for the process.  Only the windows VFS makes use of this global
6181
** variable; it is ignored by the unix VFS.
6182
**
6183
** Changing the value of this variable while a database connection is
6184
** open can result in a corrupt database.
6185
**
6186
** It is not safe to read or modify this variable in more than one
6187
** thread at a time.  It is not safe to read or modify this variable
6188
** if a [database connection] is being used at the same time in a separate
6189
** thread.
6190
** It is intended that this variable be set once
6191
** as part of process initialization and before any SQLite interface
6192
** routines have been called and that this variable remain unchanged
6193
** thereafter.
6194
**
6195
** ^The [data_store_directory pragma] may modify this variable and cause
6196
** it to point to memory obtained from [sqlite3_malloc].  ^Furthermore,
6197
** the [data_store_directory pragma] always assumes that any string
6198
** that this variable points to is held in memory obtained from
6199
** [sqlite3_malloc] and the pragma may attempt to free that memory
6200
** using [sqlite3_free].
6201
** Hence, if this variable is modified directly, either it should be
6202
** made NULL or made to point to memory obtained from [sqlite3_malloc]
6203
** or else the use of the [data_store_directory pragma] should be avoided.
6204
*/
6205
SQLITE_API SQLITE_EXTERN char *sqlite3_data_directory;
6206
6207
/*
6208
** CAPI3REF: Win32 Specific Interface
6209
**
6210
** These interfaces are available only on Windows.  The
6211
** [sqlite3_win32_set_directory] interface is used to set the value associated
6212
** with the [sqlite3_temp_directory] or [sqlite3_data_directory] variable, to
6213
** zValue, depending on the value of the type parameter.  The zValue parameter
6214
** should be NULL to cause the previous value to be freed via [sqlite3_free];
6215
** a non-NULL value will be copied into memory obtained from [sqlite3_malloc]
6216
** prior to being used.  The [sqlite3_win32_set_directory] interface returns
6217
** [SQLITE_OK] to indicate success, [SQLITE_ERROR] if the type is unsupported,
6218
** or [SQLITE_NOMEM] if memory could not be allocated.  The value of the
6219
** [sqlite3_data_directory] variable is intended to act as a replacement for
6220
** the current directory on the sub-platforms of Win32 where that concept is
6221
** not present, e.g. WinRT and UWP.  The [sqlite3_win32_set_directory8] and
6222
** [sqlite3_win32_set_directory16] interfaces behave exactly the same as the
6223
** sqlite3_win32_set_directory interface except the string parameter must be
6224
** UTF-8 or UTF-16, respectively.
6225
*/
6226
SQLITE_API int sqlite3_win32_set_directory(
6227
  unsigned long type, /* Identifier for directory being set or reset */
6228
  void *zValue        /* New value for directory being set or reset */
6229
);
6230
SQLITE_API int sqlite3_win32_set_directory8(unsigned long type, const char *zValue);
6231
SQLITE_API int sqlite3_win32_set_directory16(unsigned long type, const void *zValue);
6232
6233
/*
6234
** CAPI3REF: Win32 Directory Types
6235
**
6236
** These macros are only available on Windows.  They define the allowed values
6237
** for the type argument to the [sqlite3_win32_set_directory] interface.
6238
*/
6239
#define SQLITE_WIN32_DATA_DIRECTORY_TYPE  1
6240
#define SQLITE_WIN32_TEMP_DIRECTORY_TYPE  2
6241
6242
/*
6243
** CAPI3REF: Test For Auto-Commit Mode
6244
** KEYWORDS: {autocommit mode}
6245
** METHOD: sqlite3
6246
**
6247
** ^The sqlite3_get_autocommit() interface returns non-zero or
6248
** zero if the given database connection is or is not in autocommit mode,
6249
** respectively.  ^Autocommit mode is on by default.
6250
** ^Autocommit mode is disabled by a [BEGIN] statement.
6251
** ^Autocommit mode is re-enabled by a [COMMIT] or [ROLLBACK].
6252
**
6253
** If certain kinds of errors occur on a statement within a multi-statement
6254
** transaction (errors including [SQLITE_FULL], [SQLITE_IOERR],
6255
** [SQLITE_NOMEM], [SQLITE_BUSY], and [SQLITE_INTERRUPT]) then the
6256
** transaction might be rolled back automatically.  The only way to
6257
** find out whether SQLite automatically rolled back the transaction after
6258
** an error is to use this function.
6259
**
6260
** If another thread changes the autocommit status of the database
6261
** connection while this routine is running, then the return value
6262
** is undefined.
6263
*/
6264
SQLITE_API int sqlite3_get_autocommit(sqlite3*);
6265
6266
/*
6267
** CAPI3REF: Find The Database Handle Of A Prepared Statement
6268
** METHOD: sqlite3_stmt
6269
**
6270
** ^The sqlite3_db_handle interface returns the [database connection] handle
6271
** to which a [prepared statement] belongs.  ^The [database connection]
6272
** returned by sqlite3_db_handle is the same [database connection]
6273
** that was the first argument
6274
** to the [sqlite3_prepare_v2()] call (or its variants) that was used to
6275
** create the statement in the first place.
6276
*/
6277
SQLITE_API sqlite3 *sqlite3_db_handle(sqlite3_stmt*);
6278
6279
/*
6280
** CAPI3REF: Return The Schema Name For A Database Connection
6281
** METHOD: sqlite3
6282
**
6283
** ^The sqlite3_db_name(D,N) interface returns a pointer to the schema name
6284
** for the N-th database on database connection D, or a NULL pointer of N is
6285
** out of range.  An N alue of 0 means the main database file.  An N of 1 is
6286
** the "temp" schema.  Larger values of N correspond to various ATTACH-ed
6287
** databases.
6288
**
6289
** Space to hold the string that is returned by sqlite3_db_name() is managed
6290
** by SQLite itself.  The string might be deallocated by any operation that
6291
** changes the schema, including [ATTACH] or [DETACH] or calls to
6292
** [sqlite3_serialize()] or [sqlite3_deserialize()], even operations that
6293
** occur on a different thread.  Applications that need to
6294
** remember the string long-term should make their own copy.  Applications that
6295
** are accessing the same database connection simultaneously on multiple
6296
** threads should mutex-protect calls to this API and should make their own
6297
** private copy of the result prior to releasing the mutex.
6298
*/
6299
SQLITE_API const char *sqlite3_db_name(sqlite3 *db, int N);
6300
6301
/*
6302
** CAPI3REF: Return The Filename For A Database Connection
6303
** METHOD: sqlite3
6304
**
6305
** ^The sqlite3_db_filename(D,N) interface returns a pointer to the filename
6306
** associated with database N of connection D.
6307
** ^If there is no attached database N on the database
6308
** connection D, or if database N is a temporary or in-memory database, then
6309
** this function will return either a NULL pointer or an empty string.
6310
**
6311
** ^The string value returned by this routine is owned and managed by
6312
** the database connection.  ^The value will be valid until the database N
6313
** is [DETACH]-ed or until the database connection closes.
6314
**
6315
** ^The filename returned by this function is the output of the
6316
** xFullPathname method of the [VFS].  ^In other words, the filename
6317
** will be an absolute pathname, even if the filename used
6318
** to open the database originally was a URI or relative pathname.
6319
**
6320
** If the filename pointer returned by this routine is not NULL, then it
6321
** can be used as the filename input parameter to these routines:
6322
** <ul>
6323
** <li> [sqlite3_uri_parameter()]
6324
** <li> [sqlite3_uri_boolean()]
6325
** <li> [sqlite3_uri_int64()]
6326
** <li> [sqlite3_filename_database()]
6327
** <li> [sqlite3_filename_journal()]
6328
** <li> [sqlite3_filename_wal()]
6329
** </ul>
6330
*/
6331
SQLITE_API const char *sqlite3_db_filename(sqlite3 *db, const char *zDbName);
6332
6333
/*
6334
** CAPI3REF: Determine if a database is read-only
6335
** METHOD: sqlite3
6336
**
6337
** ^The sqlite3_db_readonly(D,N) interface returns 1 if the database N
6338
** of connection D is read-only, 0 if it is read/write, or -1 if N is not
6339
** the name of a database on connection D.
6340
*/
6341
SQLITE_API int sqlite3_db_readonly(sqlite3 *db, const char *zDbName);
6342
6343
/*
6344
** CAPI3REF: Determine the transaction state of a database
6345
** METHOD: sqlite3
6346
**
6347
** ^The sqlite3_txn_state(D,S) interface returns the current
6348
** [transaction state] of schema S in database connection D.  ^If S is NULL,
6349
** then the highest transaction state of any schema on database connection D
6350
** is returned.  Transaction states are (in order of lowest to highest):
6351
** <ol>
6352
** <li value="0"> SQLITE_TXN_NONE
6353
** <li value="1"> SQLITE_TXN_READ
6354
** <li value="2"> SQLITE_TXN_WRITE
6355
** </ol>
6356
** ^If the S argument to sqlite3_txn_state(D,S) is not the name of
6357
** a valid schema, then -1 is returned.
6358
*/
6359
SQLITE_API int sqlite3_txn_state(sqlite3*,const char *zSchema);
6360
6361
/*
6362
** CAPI3REF: Allowed return values from [sqlite3_txn_state()]
6363
** KEYWORDS: {transaction state}
6364
**
6365
** These constants define the current transaction state of a database file.
6366
** ^The [sqlite3_txn_state(D,S)] interface returns one of these
6367
** constants in order to describe the transaction state of schema S
6368
** in [database connection] D.
6369
**
6370
** <dl>
6371
** [[SQLITE_TXN_NONE]] <dt>SQLITE_TXN_NONE</dt>
6372
** <dd>The SQLITE_TXN_NONE state means that no transaction is currently
6373
** pending.</dd>
6374
**
6375
** [[SQLITE_TXN_READ]] <dt>SQLITE_TXN_READ</dt>
6376
** <dd>The SQLITE_TXN_READ state means that the database is currently
6377
** in a read transaction.  Content has been read from the database file
6378
** but nothing in the database file has changed.  The transaction state
6379
** will advanced to SQLITE_TXN_WRITE if any changes occur and there are
6380
** no other conflicting concurrent write transactions.  The transaction
6381
** state will revert to SQLITE_TXN_NONE following a [ROLLBACK] or
6382
** [COMMIT].</dd>
6383
**
6384
** [[SQLITE_TXN_WRITE]] <dt>SQLITE_TXN_WRITE</dt>
6385
** <dd>The SQLITE_TXN_WRITE state means that the database is currently
6386
** in a write transaction.  Content has been written to the database file
6387
** but has not yet committed.  The transaction state will change to
6388
** to SQLITE_TXN_NONE at the next [ROLLBACK] or [COMMIT].</dd>
6389
*/
6390
#define SQLITE_TXN_NONE  0
6391
#define SQLITE_TXN_READ  1
6392
#define SQLITE_TXN_WRITE 2
6393
6394
/*
6395
** CAPI3REF: Find the next prepared statement
6396
** METHOD: sqlite3
6397
**
6398
** ^This interface returns a pointer to the next [prepared statement] after
6399
** pStmt associated with the [database connection] pDb.  ^If pStmt is NULL
6400
** then this interface returns a pointer to the first prepared statement
6401
** associated with the database connection pDb.  ^If no prepared statement
6402
** satisfies the conditions of this routine, it returns NULL.
6403
**
6404
** The [database connection] pointer D in a call to
6405
** [sqlite3_next_stmt(D,S)] must refer to an open database
6406
** connection and in particular must not be a NULL pointer.
6407
*/
6408
SQLITE_API sqlite3_stmt *sqlite3_next_stmt(sqlite3 *pDb, sqlite3_stmt *pStmt);
6409
6410
/*
6411
** CAPI3REF: Commit And Rollback Notification Callbacks
6412
** METHOD: sqlite3
6413
**
6414
** ^The sqlite3_commit_hook() interface registers a callback
6415
** function to be invoked whenever a transaction is [COMMIT | committed].
6416
** ^Any callback set by a previous call to sqlite3_commit_hook()
6417
** for the same database connection is overridden.
6418
** ^The sqlite3_rollback_hook() interface registers a callback
6419
** function to be invoked whenever a transaction is [ROLLBACK | rolled back].
6420
** ^Any callback set by a previous call to sqlite3_rollback_hook()
6421
** for the same database connection is overridden.
6422
** ^The pArg argument is passed through to the callback.
6423
** ^If the callback on a commit hook function returns non-zero,
6424
** then the commit is converted into a rollback.
6425
**
6426
** ^The sqlite3_commit_hook(D,C,P) and sqlite3_rollback_hook(D,C,P) functions
6427
** return the P argument from the previous call of the same function
6428
** on the same [database connection] D, or NULL for
6429
** the first call for each function on D.
6430
**
6431
** The commit and rollback hook callbacks are not reentrant.
6432
** The callback implementation must not do anything that will modify
6433
** the database connection that invoked the callback.  Any actions
6434
** to modify the database connection must be deferred until after the
6435
** completion of the [sqlite3_step()] call that triggered the commit
6436
** or rollback hook in the first place.
6437
** Note that running any other SQL statements, including SELECT statements,
6438
** or merely calling [sqlite3_prepare_v2()] and [sqlite3_step()] will modify
6439
** the database connections for the meaning of "modify" in this paragraph.
6440
**
6441
** ^Registering a NULL function disables the callback.
6442
**
6443
** ^When the commit hook callback routine returns zero, the [COMMIT]
6444
** operation is allowed to continue normally.  ^If the commit hook
6445
** returns non-zero, then the [COMMIT] is converted into a [ROLLBACK].
6446
** ^The rollback hook is invoked on a rollback that results from a commit
6447
** hook returning non-zero, just as it would be with any other rollback.
6448
**
6449
** ^For the purposes of this API, a transaction is said to have been
6450
** rolled back if an explicit "ROLLBACK" statement is executed, or
6451
** an error or constraint causes an implicit rollback to occur.
6452
** ^The rollback callback is not invoked if a transaction is
6453
** automatically rolled back because the database connection is closed.
6454
**
6455
** See also the [sqlite3_update_hook()] interface.
6456
*/
6457
SQLITE_API void *sqlite3_commit_hook(sqlite3*, int(*)(void*), void*);
6458
SQLITE_API void *sqlite3_rollback_hook(sqlite3*, void(*)(void *), void*);
6459
6460
/*
6461
** CAPI3REF: Autovacuum Compaction Amount Callback
6462
** METHOD: sqlite3
6463
**
6464
** ^The sqlite3_autovacuum_pages(D,C,P,X) interface registers a callback
6465
** function C that is invoked prior to each autovacuum of the database
6466
** file.  ^The callback is passed a copy of the generic data pointer (P),
6467
** the schema-name of the attached database that is being autovacuumed,
6468
** the the size of the database file in pages, the number of free pages,
6469
** and the number of bytes per page, respectively.  The callback should
6470
** return the number of free pages that should be removed by the
6471
** autovacuum.  ^If the callback returns zero, then no autovacuum happens.
6472
** ^If the value returned is greater than or equal to the number of
6473
** free pages, then a complete autovacuum happens.
6474
**
6475
** <p>^If there are multiple ATTACH-ed database files that are being
6476
** modified as part of a transaction commit, then the autovacuum pages
6477
** callback is invoked separately for each file.
6478
**
6479
** <p><b>The callback is not reentrant.</b> The callback function should
6480
** not attempt to invoke any other SQLite interface.  If it does, bad
6481
** things may happen, including segmentation faults and corrupt database
6482
** files.  The callback function should be a simple function that
6483
** does some arithmetic on its input parameters and returns a result.
6484
**
6485
** ^The X parameter to sqlite3_autovacuum_pages(D,C,P,X) is an optional
6486
** destructor for the P parameter.  ^If X is not NULL, then X(P) is
6487
** invoked whenever the database connection closes or when the callback
6488
** is overwritten by another invocation of sqlite3_autovacuum_pages().
6489
**
6490
** <p>^There is only one autovacuum pages callback per database connection.
6491
** ^Each call to the sqlite3_autovacuum_pages() interface overrides all
6492
** previous invocations for that database connection.  ^If the callback
6493
** argument (C) to sqlite3_autovacuum_pages(D,C,P,X) is a NULL pointer,
6494
** then the autovacuum steps callback is cancelled.  The return value
6495
** from sqlite3_autovacuum_pages() is normally SQLITE_OK, but might
6496
** be some other error code if something goes wrong.  The current
6497
** implementation will only return SQLITE_OK or SQLITE_MISUSE, but other
6498
** return codes might be added in future releases.
6499
**
6500
** <p>If no autovacuum pages callback is specified (the usual case) or
6501
** a NULL pointer is provided for the callback,
6502
** then the default behavior is to vacuum all free pages.  So, in other
6503
** words, the default behavior is the same as if the callback function
6504
** were something like this:
6505
**
6506
** <blockquote><pre>
6507
** &nbsp;   unsigned int demonstration_autovac_pages_callback(
6508
** &nbsp;     void *pClientData,
6509
** &nbsp;     const char *zSchema,
6510
** &nbsp;     unsigned int nDbPage,
6511
** &nbsp;     unsigned int nFreePage,
6512
** &nbsp;     unsigned int nBytePerPage
6513
** &nbsp;   ){
6514
** &nbsp;     return nFreePage;
6515
** &nbsp;   }
6516
** </pre></blockquote>
6517
*/
6518
SQLITE_API int sqlite3_autovacuum_pages(
6519
  sqlite3 *db,
6520
  unsigned int(*)(void*,const char*,unsigned int,unsigned int,unsigned int),
6521
  void*,
6522
  void(*)(void*)
6523
);
6524
6525
6526
/*
6527
** CAPI3REF: Data Change Notification Callbacks
6528
** METHOD: sqlite3
6529
**
6530
** ^The sqlite3_update_hook() interface registers a callback function
6531
** with the [database connection] identified by the first argument
6532
** to be invoked whenever a row is updated, inserted or deleted in
6533
** a [rowid table].
6534
** ^Any callback set by a previous call to this function
6535
** for the same database connection is overridden.
6536
**
6537
** ^The second argument is a pointer to the function to invoke when a
6538
** row is updated, inserted or deleted in a rowid table.
6539
** ^The first argument to the callback is a copy of the third argument
6540
** to sqlite3_update_hook().
6541
** ^The second callback argument is one of [SQLITE_INSERT], [SQLITE_DELETE],
6542
** or [SQLITE_UPDATE], depending on the operation that caused the callback
6543
** to be invoked.
6544
** ^The third and fourth arguments to the callback contain pointers to the
6545
** database and table name containing the affected row.
6546
** ^The final callback parameter is the [rowid] of the row.
6547
** ^In the case of an update, this is the [rowid] after the update takes place.
6548
**
6549
** ^(The update hook is not invoked when internal system tables are
6550
** modified (i.e. sqlite_sequence).)^
6551
** ^The update hook is not invoked when [WITHOUT ROWID] tables are modified.
6552
**
6553
** ^In the current implementation, the update hook
6554
** is not invoked when conflicting rows are deleted because of an
6555
** [ON CONFLICT | ON CONFLICT REPLACE] clause.  ^Nor is the update hook
6556
** invoked when rows are deleted using the [truncate optimization].
6557
** The exceptions defined in this paragraph might change in a future
6558
** release of SQLite.
6559
**
6560
** The update hook implementation must not do anything that will modify
6561
** the database connection that invoked the update hook.  Any actions
6562
** to modify the database connection must be deferred until after the
6563
** completion of the [sqlite3_step()] call that triggered the update hook.
6564
** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
6565
** database connections for the meaning of "modify" in this paragraph.
6566
**
6567
** ^The sqlite3_update_hook(D,C,P) function
6568
** returns the P argument from the previous call
6569
** on the same [database connection] D, or NULL for
6570
** the first call on D.
6571
**
6572
** See also the [sqlite3_commit_hook()], [sqlite3_rollback_hook()],
6573
** and [sqlite3_preupdate_hook()] interfaces.
6574
*/
6575
SQLITE_API void *sqlite3_update_hook(
6576
  sqlite3*,
6577
  void(*)(void *,int ,char const *,char const *,sqlite3_int64),
6578
  void*
6579
);
6580
6581
/*
6582
** CAPI3REF: Enable Or Disable Shared Pager Cache
6583
**
6584
** ^(This routine enables or disables the sharing of the database cache
6585
** and schema data structures between [database connection | connections]
6586
** to the same database. Sharing is enabled if the argument is true
6587
** and disabled if the argument is false.)^
6588
**
6589
** ^Cache sharing is enabled and disabled for an entire process.
6590
** This is a change as of SQLite [version 3.5.0] ([dateof:3.5.0]).
6591
** In prior versions of SQLite,
6592
** sharing was enabled or disabled for each thread separately.
6593
**
6594
** ^(The cache sharing mode set by this interface effects all subsequent
6595
** calls to [sqlite3_open()], [sqlite3_open_v2()], and [sqlite3_open16()].
6596
** Existing database connections continue to use the sharing mode
6597
** that was in effect at the time they were opened.)^
6598
**
6599
** ^(This routine returns [SQLITE_OK] if shared cache was enabled or disabled
6600
** successfully.  An [error code] is returned otherwise.)^
6601
**
6602
** ^Shared cache is disabled by default. It is recommended that it stay
6603
** that way.  In other words, do not use this routine.  This interface
6604
** continues to be provided for historical compatibility, but its use is
6605
** discouraged.  Any use of shared cache is discouraged.  If shared cache
6606
** must be used, it is recommended that shared cache only be enabled for
6607
** individual database connections using the [sqlite3_open_v2()] interface
6608
** with the [SQLITE_OPEN_SHAREDCACHE] flag.
6609
**
6610
** Note: This method is disabled on MacOS X 10.7 and iOS version 5.0
6611
** and will always return SQLITE_MISUSE. On those systems,
6612
** shared cache mode should be enabled per-database connection via
6613
** [sqlite3_open_v2()] with [SQLITE_OPEN_SHAREDCACHE].
6614
**
6615
** This interface is threadsafe on processors where writing a
6616
** 32-bit integer is atomic.
6617
**
6618
** See Also:  [SQLite Shared-Cache Mode]
6619
*/
6620
SQLITE_API int sqlite3_enable_shared_cache(int);
6621
6622
/*
6623
** CAPI3REF: Attempt To Free Heap Memory
6624
**
6625
** ^The sqlite3_release_memory() interface attempts to free N bytes
6626
** of heap memory by deallocating non-essential memory allocations
6627
** held by the database library.   Memory used to cache database
6628
** pages to improve performance is an example of non-essential memory.
6629
** ^sqlite3_release_memory() returns the number of bytes actually freed,
6630
** which might be more or less than the amount requested.
6631
** ^The sqlite3_release_memory() routine is a no-op returning zero
6632
** if SQLite is not compiled with [SQLITE_ENABLE_MEMORY_MANAGEMENT].
6633
**
6634
** See also: [sqlite3_db_release_memory()]
6635
*/
6636
SQLITE_API int sqlite3_release_memory(int);
6637
6638
/*
6639
** CAPI3REF: Free Memory Used By A Database Connection
6640
** METHOD: sqlite3
6641
**
6642
** ^The sqlite3_db_release_memory(D) interface attempts to free as much heap
6643
** memory as possible from database connection D. Unlike the
6644
** [sqlite3_release_memory()] interface, this interface is in effect even
6645
** when the [SQLITE_ENABLE_MEMORY_MANAGEMENT] compile-time option is
6646
** omitted.
6647
**
6648
** See also: [sqlite3_release_memory()]
6649
*/
6650
SQLITE_API int sqlite3_db_release_memory(sqlite3*);
6651
6652
/*
6653
** CAPI3REF: Impose A Limit On Heap Size
6654
**
6655
** These interfaces impose limits on the amount of heap memory that will be
6656
** by all database connections within a single process.
6657
**
6658
** ^The sqlite3_soft_heap_limit64() interface sets and/or queries the
6659
** soft limit on the amount of heap memory that may be allocated by SQLite.
6660
** ^SQLite strives to keep heap memory utilization below the soft heap
6661
** limit by reducing the number of pages held in the page cache
6662
** as heap memory usages approaches the limit.
6663
** ^The soft heap limit is "soft" because even though SQLite strives to stay
6664
** below the limit, it will exceed the limit rather than generate
6665
** an [SQLITE_NOMEM] error.  In other words, the soft heap limit
6666
** is advisory only.
6667
**
6668
** ^The sqlite3_hard_heap_limit64(N) interface sets a hard upper bound of
6669
** N bytes on the amount of memory that will be allocated.  ^The
6670
** sqlite3_hard_heap_limit64(N) interface is similar to
6671
** sqlite3_soft_heap_limit64(N) except that memory allocations will fail
6672
** when the hard heap limit is reached.
6673
**
6674
** ^The return value from both sqlite3_soft_heap_limit64() and
6675
** sqlite3_hard_heap_limit64() is the size of
6676
** the heap limit prior to the call, or negative in the case of an
6677
** error.  ^If the argument N is negative
6678
** then no change is made to the heap limit.  Hence, the current
6679
** size of heap limits can be determined by invoking
6680
** sqlite3_soft_heap_limit64(-1) or sqlite3_hard_heap_limit(-1).
6681
**
6682
** ^Setting the heap limits to zero disables the heap limiter mechanism.
6683
**
6684
** ^The soft heap limit may not be greater than the hard heap limit.
6685
** ^If the hard heap limit is enabled and if sqlite3_soft_heap_limit(N)
6686
** is invoked with a value of N that is greater than the hard heap limit,
6687
** the the soft heap limit is set to the value of the hard heap limit.
6688
** ^The soft heap limit is automatically enabled whenever the hard heap
6689
** limit is enabled. ^When sqlite3_hard_heap_limit64(N) is invoked and
6690
** the soft heap limit is outside the range of 1..N, then the soft heap
6691
** limit is set to N.  ^Invoking sqlite3_soft_heap_limit64(0) when the
6692
** hard heap limit is enabled makes the soft heap limit equal to the
6693
** hard heap limit.
6694
**
6695
** The memory allocation limits can also be adjusted using
6696
** [PRAGMA soft_heap_limit] and [PRAGMA hard_heap_limit].
6697
**
6698
** ^(The heap limits are not enforced in the current implementation
6699
** if one or more of following conditions are true:
6700
**
6701
** <ul>
6702
** <li> The limit value is set to zero.
6703
** <li> Memory accounting is disabled using a combination of the
6704
**      [sqlite3_config]([SQLITE_CONFIG_MEMSTATUS],...) start-time option and
6705
**      the [SQLITE_DEFAULT_MEMSTATUS] compile-time option.
6706
** <li> An alternative page cache implementation is specified using
6707
**      [sqlite3_config]([SQLITE_CONFIG_PCACHE2],...).
6708
** <li> The page cache allocates from its own memory pool supplied
6709
**      by [sqlite3_config]([SQLITE_CONFIG_PAGECACHE],...) rather than
6710
**      from the heap.
6711
** </ul>)^
6712
**
6713
** The circumstances under which SQLite will enforce the heap limits may
6714
** changes in future releases of SQLite.
6715
*/
6716
SQLITE_API sqlite3_int64 sqlite3_soft_heap_limit64(sqlite3_int64 N);
6717
SQLITE_API sqlite3_int64 sqlite3_hard_heap_limit64(sqlite3_int64 N);
6718
6719
/*
6720
** CAPI3REF: Deprecated Soft Heap Limit Interface
6721
** DEPRECATED
6722
**
6723
** This is a deprecated version of the [sqlite3_soft_heap_limit64()]
6724
** interface.  This routine is provided for historical compatibility
6725
** only.  All new applications should use the
6726
** [sqlite3_soft_heap_limit64()] interface rather than this one.
6727
*/
6728
SQLITE_API SQLITE_DEPRECATED void sqlite3_soft_heap_limit(int N);
6729
6730
6731
/*
6732
** CAPI3REF: Extract Metadata About A Column Of A Table
6733
** METHOD: sqlite3
6734
**
6735
** ^(The sqlite3_table_column_metadata(X,D,T,C,....) routine returns
6736
** information about column C of table T in database D
6737
** on [database connection] X.)^  ^The sqlite3_table_column_metadata()
6738
** interface returns SQLITE_OK and fills in the non-NULL pointers in
6739
** the final five arguments with appropriate values if the specified
6740
** column exists.  ^The sqlite3_table_column_metadata() interface returns
6741
** SQLITE_ERROR if the specified column does not exist.
6742
** ^If the column-name parameter to sqlite3_table_column_metadata() is a
6743
** NULL pointer, then this routine simply checks for the existence of the
6744
** table and returns SQLITE_OK if the table exists and SQLITE_ERROR if it
6745
** does not.  If the table name parameter T in a call to
6746
** sqlite3_table_column_metadata(X,D,T,C,...) is NULL then the result is
6747
** undefined behavior.
6748
**
6749
** ^The column is identified by the second, third and fourth parameters to
6750
** this function. ^(The second parameter is either the name of the database
6751
** (i.e. "main", "temp", or an attached database) containing the specified
6752
** table or NULL.)^ ^If it is NULL, then all attached databases are searched
6753
** for the table using the same algorithm used by the database engine to
6754
** resolve unqualified table references.
6755
**
6756
** ^The third and fourth parameters to this function are the table and column
6757
** name of the desired column, respectively.
6758
**
6759
** ^Metadata is returned by writing to the memory locations passed as the 5th
6760
** and subsequent parameters to this function. ^Any of these arguments may be
6761
** NULL, in which case the corresponding element of metadata is omitted.
6762
**
6763
** ^(<blockquote>
6764
** <table border="1">
6765
** <tr><th> Parameter <th> Output<br>Type <th>  Description
6766
**
6767
** <tr><td> 5th <td> const char* <td> Data type
6768
** <tr><td> 6th <td> const char* <td> Name of default collation sequence
6769
** <tr><td> 7th <td> int         <td> True if column has a NOT NULL constraint
6770
** <tr><td> 8th <td> int         <td> True if column is part of the PRIMARY KEY
6771
** <tr><td> 9th <td> int         <td> True if column is [AUTOINCREMENT]
6772
** </table>
6773
** </blockquote>)^
6774
**
6775
** ^The memory pointed to by the character pointers returned for the
6776
** declaration type and collation sequence is valid until the next
6777
** call to any SQLite API function.
6778
**
6779
** ^If the specified table is actually a view, an [error code] is returned.
6780
**
6781
** ^If the specified column is "rowid", "oid" or "_rowid_" and the table
6782
** is not a [WITHOUT ROWID] table and an
6783
** [INTEGER PRIMARY KEY] column has been explicitly declared, then the output
6784
** parameters are set for the explicitly declared column. ^(If there is no
6785
** [INTEGER PRIMARY KEY] column, then the outputs
6786
** for the [rowid] are set as follows:
6787
**
6788
** <pre>
6789
**     data type: "INTEGER"
6790
**     collation sequence: "BINARY"
6791
**     not null: 0
6792
**     primary key: 1
6793
**     auto increment: 0
6794
** </pre>)^
6795
**
6796
** ^This function causes all database schemas to be read from disk and
6797
** parsed, if that has not already been done, and returns an error if
6798
** any errors are encountered while loading the schema.
6799
*/
6800
SQLITE_API int sqlite3_table_column_metadata(
6801
  sqlite3 *db,                /* Connection handle */
6802
  const char *zDbName,        /* Database name or NULL */
6803
  const char *zTableName,     /* Table name */
6804
  const char *zColumnName,    /* Column name */
6805
  char const **pzDataType,    /* OUTPUT: Declared data type */
6806
  char const **pzCollSeq,     /* OUTPUT: Collation sequence name */
6807
  int *pNotNull,              /* OUTPUT: True if NOT NULL constraint exists */
6808
  int *pPrimaryKey,           /* OUTPUT: True if column part of PK */
6809
  int *pAutoinc               /* OUTPUT: True if column is auto-increment */
6810
);
6811
6812
/*
6813
** CAPI3REF: Load An Extension
6814
** METHOD: sqlite3
6815
**
6816
** ^This interface loads an SQLite extension library from the named file.
6817
**
6818
** ^The sqlite3_load_extension() interface attempts to load an
6819
** [SQLite extension] library contained in the file zFile.  If
6820
** the file cannot be loaded directly, attempts are made to load
6821
** with various operating-system specific extensions added.
6822
** So for example, if "samplelib" cannot be loaded, then names like
6823
** "samplelib.so" or "samplelib.dylib" or "samplelib.dll" might
6824
** be tried also.
6825
**
6826
** ^The entry point is zProc.
6827
** ^(zProc may be 0, in which case SQLite will try to come up with an
6828
** entry point name on its own.  It first tries "sqlite3_extension_init".
6829
** If that does not work, it constructs a name "sqlite3_X_init" where the
6830
** X is consists of the lower-case equivalent of all ASCII alphabetic
6831
** characters in the filename from the last "/" to the first following
6832
** "." and omitting any initial "lib".)^
6833
** ^The sqlite3_load_extension() interface returns
6834
** [SQLITE_OK] on success and [SQLITE_ERROR] if something goes wrong.
6835
** ^If an error occurs and pzErrMsg is not 0, then the
6836
** [sqlite3_load_extension()] interface shall attempt to
6837
** fill *pzErrMsg with error message text stored in memory
6838
** obtained from [sqlite3_malloc()]. The calling function
6839
** should free this memory by calling [sqlite3_free()].
6840
**
6841
** ^Extension loading must be enabled using
6842
** [sqlite3_enable_load_extension()] or
6843
** [sqlite3_db_config](db,[SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION],1,NULL)
6844
** prior to calling this API,
6845
** otherwise an error will be returned.
6846
**
6847
** <b>Security warning:</b> It is recommended that the
6848
** [SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION] method be used to enable only this
6849
** interface.  The use of the [sqlite3_enable_load_extension()] interface
6850
** should be avoided.  This will keep the SQL function [load_extension()]
6851
** disabled and prevent SQL injections from giving attackers
6852
** access to extension loading capabilities.
6853
**
6854
** See also the [load_extension() SQL function].
6855
*/
6856
SQLITE_API int sqlite3_load_extension(
6857
  sqlite3 *db,          /* Load the extension into this database connection */
6858
  const char *zFile,    /* Name of the shared library containing extension */
6859
  const char *zProc,    /* Entry point.  Derived from zFile if 0 */
6860
  char **pzErrMsg       /* Put error message here if not 0 */
6861
);
6862
6863
/*
6864
** CAPI3REF: Enable Or Disable Extension Loading
6865
** METHOD: sqlite3
6866
**
6867
** ^So as not to open security holes in older applications that are
6868
** unprepared to deal with [extension loading], and as a means of disabling
6869
** [extension loading] while evaluating user-entered SQL, the following API
6870
** is provided to turn the [sqlite3_load_extension()] mechanism on and off.
6871
**
6872
** ^Extension loading is off by default.
6873
** ^Call the sqlite3_enable_load_extension() routine with onoff==1
6874
** to turn extension loading on and call it with onoff==0 to turn
6875
** it back off again.
6876
**
6877
** ^This interface enables or disables both the C-API
6878
** [sqlite3_load_extension()] and the SQL function [load_extension()].
6879
** ^(Use [sqlite3_db_config](db,[SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION],..)
6880
** to enable or disable only the C-API.)^
6881
**
6882
** <b>Security warning:</b> It is recommended that extension loading
6883
** be enabled using the [SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION] method
6884
** rather than this interface, so the [load_extension()] SQL function
6885
** remains disabled. This will prevent SQL injections from giving attackers
6886
** access to extension loading capabilities.
6887
*/
6888
SQLITE_API int sqlite3_enable_load_extension(sqlite3 *db, int onoff);
6889
6890
/*
6891
** CAPI3REF: Automatically Load Statically Linked Extensions
6892
**
6893
** ^This interface causes the xEntryPoint() function to be invoked for
6894
** each new [database connection] that is created.  The idea here is that
6895
** xEntryPoint() is the entry point for a statically linked [SQLite extension]
6896
** that is to be automatically loaded into all new database connections.
6897
**
6898
** ^(Even though the function prototype shows that xEntryPoint() takes
6899
** no arguments and returns void, SQLite invokes xEntryPoint() with three
6900
** arguments and expects an integer result as if the signature of the
6901
** entry point where as follows:
6902
**
6903
** <blockquote><pre>
6904
** &nbsp;  int xEntryPoint(
6905
** &nbsp;    sqlite3 *db,
6906
** &nbsp;    const char **pzErrMsg,
6907
** &nbsp;    const struct sqlite3_api_routines *pThunk
6908
** &nbsp;  );
6909
** </pre></blockquote>)^
6910
**
6911
** If the xEntryPoint routine encounters an error, it should make *pzErrMsg
6912
** point to an appropriate error message (obtained from [sqlite3_mprintf()])
6913
** and return an appropriate [error code].  ^SQLite ensures that *pzErrMsg
6914
** is NULL before calling the xEntryPoint().  ^SQLite will invoke
6915
** [sqlite3_free()] on *pzErrMsg after xEntryPoint() returns.  ^If any
6916
** xEntryPoint() returns an error, the [sqlite3_open()], [sqlite3_open16()],
6917
** or [sqlite3_open_v2()] call that provoked the xEntryPoint() will fail.
6918
**
6919
** ^Calling sqlite3_auto_extension(X) with an entry point X that is already
6920
** on the list of automatic extensions is a harmless no-op. ^No entry point
6921
** will be called more than once for each database connection that is opened.
6922
**
6923
** See also: [sqlite3_reset_auto_extension()]
6924
** and [sqlite3_cancel_auto_extension()]
6925
*/
6926
SQLITE_API int sqlite3_auto_extension(void(*xEntryPoint)(void));
6927
6928
/*
6929
** CAPI3REF: Cancel Automatic Extension Loading
6930
**
6931
** ^The [sqlite3_cancel_auto_extension(X)] interface unregisters the
6932
** initialization routine X that was registered using a prior call to
6933
** [sqlite3_auto_extension(X)].  ^The [sqlite3_cancel_auto_extension(X)]
6934
** routine returns 1 if initialization routine X was successfully
6935
** unregistered and it returns 0 if X was not on the list of initialization
6936
** routines.
6937
*/
6938
SQLITE_API int sqlite3_cancel_auto_extension(void(*xEntryPoint)(void));
6939
6940
/*
6941
** CAPI3REF: Reset Automatic Extension Loading
6942
**
6943
** ^This interface disables all automatic extensions previously
6944
** registered using [sqlite3_auto_extension()].
6945
*/
6946
SQLITE_API void sqlite3_reset_auto_extension(void);
6947
6948
/*
6949
** The interface to the virtual-table mechanism is currently considered
6950
** to be experimental.  The interface might change in incompatible ways.
6951
** If this is a problem for you, do not use the interface at this time.
6952
**
6953
** When the virtual-table mechanism stabilizes, we will declare the
6954
** interface fixed, support it indefinitely, and remove this comment.
6955
*/
6956
6957
/*
6958
** Structures used by the virtual table interface
6959
*/
6960
typedef struct sqlite3_vtab sqlite3_vtab;
6961
typedef struct sqlite3_index_info sqlite3_index_info;
6962
typedef struct sqlite3_vtab_cursor sqlite3_vtab_cursor;
6963
typedef struct sqlite3_module sqlite3_module;
6964
6965
/*
6966
** CAPI3REF: Virtual Table Object
6967
** KEYWORDS: sqlite3_module {virtual table module}
6968
**
6969
** This structure, sometimes called a "virtual table module",
6970
** defines the implementation of a [virtual table].
6971
** This structure consists mostly of methods for the module.
6972
**
6973
** ^A virtual table module is created by filling in a persistent
6974
** instance of this structure and passing a pointer to that instance
6975
** to [sqlite3_create_module()] or [sqlite3_create_module_v2()].
6976
** ^The registration remains valid until it is replaced by a different
6977
** module or until the [database connection] closes.  The content
6978
** of this structure must not change while it is registered with
6979
** any database connection.
6980
*/
6981
struct sqlite3_module {
6982
  int iVersion;
6983
  int (*xCreate)(sqlite3*, void *pAux,
6984
               int argc, const char *const*argv,
6985
               sqlite3_vtab **ppVTab, char**);
6986
  int (*xConnect)(sqlite3*, void *pAux,
6987
               int argc, const char *const*argv,
6988
               sqlite3_vtab **ppVTab, char**);
6989
  int (*xBestIndex)(sqlite3_vtab *pVTab, sqlite3_index_info*);
6990
  int (*xDisconnect)(sqlite3_vtab *pVTab);
6991
  int (*xDestroy)(sqlite3_vtab *pVTab);
6992
  int (*xOpen)(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor);
6993
  int (*xClose)(sqlite3_vtab_cursor*);
6994
  int (*xFilter)(sqlite3_vtab_cursor*, int idxNum, const char *idxStr,
6995
                int argc, sqlite3_value **argv);
6996
  int (*xNext)(sqlite3_vtab_cursor*);
6997
  int (*xEof)(sqlite3_vtab_cursor*);
6998
  int (*xColumn)(sqlite3_vtab_cursor*, sqlite3_context*, int);
6999
  int (*xRowid)(sqlite3_vtab_cursor*, sqlite3_int64 *pRowid);
7000
  int (*xUpdate)(sqlite3_vtab *, int, sqlite3_value **, sqlite3_int64 *);
7001
  int (*xBegin)(sqlite3_vtab *pVTab);
7002
  int (*xSync)(sqlite3_vtab *pVTab);
7003
  int (*xCommit)(sqlite3_vtab *pVTab);
7004
  int (*xRollback)(sqlite3_vtab *pVTab);
7005
  int (*xFindFunction)(sqlite3_vtab *pVtab, int nArg, const char *zName,
7006
                       void (**pxFunc)(sqlite3_context*,int,sqlite3_value**),
7007
                       void **ppArg);
7008
  int (*xRename)(sqlite3_vtab *pVtab, const char *zNew);
7009
  /* The methods above are in version 1 of the sqlite_module object. Those
7010
  ** below are for version 2 and greater. */
7011
  int (*xSavepoint)(sqlite3_vtab *pVTab, int);
7012
  int (*xRelease)(sqlite3_vtab *pVTab, int);
7013
  int (*xRollbackTo)(sqlite3_vtab *pVTab, int);
7014
  /* The methods above are in versions 1 and 2 of the sqlite_module object.
7015
  ** Those below are for version 3 and greater. */
7016
  int (*xShadowName)(const char*);
7017
};
7018
7019
/*
7020
** CAPI3REF: Virtual Table Indexing Information
7021
** KEYWORDS: sqlite3_index_info
7022
**
7023
** The sqlite3_index_info structure and its substructures is used as part
7024
** of the [virtual table] interface to
7025
** pass information into and receive the reply from the [xBestIndex]
7026
** method of a [virtual table module].  The fields under **Inputs** are the
7027
** inputs to xBestIndex and are read-only.  xBestIndex inserts its
7028
** results into the **Outputs** fields.
7029
**
7030
** ^(The aConstraint[] array records WHERE clause constraints of the form:
7031
**
7032
** <blockquote>column OP expr</blockquote>
7033
**
7034
** where OP is =, &lt;, &lt;=, &gt;, or &gt;=.)^  ^(The particular operator is
7035
** stored in aConstraint[].op using one of the
7036
** [SQLITE_INDEX_CONSTRAINT_EQ | SQLITE_INDEX_CONSTRAINT_ values].)^
7037
** ^(The index of the column is stored in
7038
** aConstraint[].iColumn.)^  ^(aConstraint[].usable is TRUE if the
7039
** expr on the right-hand side can be evaluated (and thus the constraint
7040
** is usable) and false if it cannot.)^
7041
**
7042
** ^The optimizer automatically inverts terms of the form "expr OP column"
7043
** and makes other simplifications to the WHERE clause in an attempt to
7044
** get as many WHERE clause terms into the form shown above as possible.
7045
** ^The aConstraint[] array only reports WHERE clause terms that are
7046
** relevant to the particular virtual table being queried.
7047
**
7048
** ^Information about the ORDER BY clause is stored in aOrderBy[].
7049
** ^Each term of aOrderBy records a column of the ORDER BY clause.
7050
**
7051
** The colUsed field indicates which columns of the virtual table may be
7052
** required by the current scan. Virtual table columns are numbered from
7053
** zero in the order in which they appear within the CREATE TABLE statement
7054
** passed to sqlite3_declare_vtab(). For the first 63 columns (columns 0-62),
7055
** the corresponding bit is set within the colUsed mask if the column may be
7056
** required by SQLite. If the table has at least 64 columns and any column
7057
** to the right of the first 63 is required, then bit 63 of colUsed is also
7058
** set. In other words, column iCol may be required if the expression
7059
** (colUsed & ((sqlite3_uint64)1 << (iCol>=63 ? 63 : iCol))) evaluates to
7060
** non-zero.
7061
**
7062
** The [xBestIndex] method must fill aConstraintUsage[] with information
7063
** about what parameters to pass to xFilter.  ^If argvIndex>0 then
7064
** the right-hand side of the corresponding aConstraint[] is evaluated
7065
** and becomes the argvIndex-th entry in argv.  ^(If aConstraintUsage[].omit
7066
** is true, then the constraint is assumed to be fully handled by the
7067
** virtual table and might not be checked again by the byte code.)^ ^(The
7068
** aConstraintUsage[].omit flag is an optimization hint. When the omit flag
7069
** is left in its default setting of false, the constraint will always be
7070
** checked separately in byte code.  If the omit flag is change to true, then
7071
** the constraint may or may not be checked in byte code.  In other words,
7072
** when the omit flag is true there is no guarantee that the constraint will
7073
** not be checked again using byte code.)^
7074
**
7075
** ^The idxNum and idxPtr values are recorded and passed into the
7076
** [xFilter] method.
7077
** ^[sqlite3_free()] is used to free idxPtr if and only if
7078
** needToFreeIdxPtr is true.
7079
**
7080
** ^The orderByConsumed means that output from [xFilter]/[xNext] will occur in
7081
** the correct order to satisfy the ORDER BY clause so that no separate
7082
** sorting step is required.
7083
**
7084
** ^The estimatedCost value is an estimate of the cost of a particular
7085
** strategy. A cost of N indicates that the cost of the strategy is similar
7086
** to a linear scan of an SQLite table with N rows. A cost of log(N)
7087
** indicates that the expense of the operation is similar to that of a
7088
** binary search on a unique indexed field of an SQLite table with N rows.
7089
**
7090
** ^The estimatedRows value is an estimate of the number of rows that
7091
** will be returned by the strategy.
7092
**
7093
** The xBestIndex method may optionally populate the idxFlags field with a
7094
** mask of SQLITE_INDEX_SCAN_* flags. Currently there is only one such flag -
7095
** SQLITE_INDEX_SCAN_UNIQUE. If the xBestIndex method sets this flag, SQLite
7096
** assumes that the strategy may visit at most one row.
7097
**
7098
** Additionally, if xBestIndex sets the SQLITE_INDEX_SCAN_UNIQUE flag, then
7099
** SQLite also assumes that if a call to the xUpdate() method is made as
7100
** part of the same statement to delete or update a virtual table row and the
7101
** implementation returns SQLITE_CONSTRAINT, then there is no need to rollback
7102
** any database changes. In other words, if the xUpdate() returns
7103
** SQLITE_CONSTRAINT, the database contents must be exactly as they were
7104
** before xUpdate was called. By contrast, if SQLITE_INDEX_SCAN_UNIQUE is not
7105
** set and xUpdate returns SQLITE_CONSTRAINT, any database changes made by
7106
** the xUpdate method are automatically rolled back by SQLite.
7107
**
7108
** IMPORTANT: The estimatedRows field was added to the sqlite3_index_info
7109
** structure for SQLite [version 3.8.2] ([dateof:3.8.2]).
7110
** If a virtual table extension is
7111
** used with an SQLite version earlier than 3.8.2, the results of attempting
7112
** to read or write the estimatedRows field are undefined (but are likely
7113
** to include crashing the application). The estimatedRows field should
7114
** therefore only be used if [sqlite3_libversion_number()] returns a
7115
** value greater than or equal to 3008002. Similarly, the idxFlags field
7116
** was added for [version 3.9.0] ([dateof:3.9.0]).
7117
** It may therefore only be used if
7118
** sqlite3_libversion_number() returns a value greater than or equal to
7119
** 3009000.
7120
*/
7121
struct sqlite3_index_info {
7122
  /* Inputs */
7123
  int nConstraint;           /* Number of entries in aConstraint */
7124
  struct sqlite3_index_constraint {
7125
     int iColumn;              /* Column constrained.  -1 for ROWID */
7126
     unsigned char op;         /* Constraint operator */
7127
     unsigned char usable;     /* True if this constraint is usable */
7128
     int iTermOffset;          /* Used internally - xBestIndex should ignore */
7129
  } *aConstraint;            /* Table of WHERE clause constraints */
7130
  int nOrderBy;              /* Number of terms in the ORDER BY clause */
7131
  struct sqlite3_index_orderby {
7132
     int iColumn;              /* Column number */
7133
     unsigned char desc;       /* True for DESC.  False for ASC. */
7134
  } *aOrderBy;               /* The ORDER BY clause */
7135
  /* Outputs */
7136
  struct sqlite3_index_constraint_usage {
7137
    int argvIndex;           /* if >0, constraint is part of argv to xFilter */
7138
    unsigned char omit;      /* Do not code a test for this constraint */
7139
  } *aConstraintUsage;
7140
  int idxNum;                /* Number used to identify the index */
7141
  char *idxStr;              /* String, possibly obtained from sqlite3_malloc */
7142
  int needToFreeIdxStr;      /* Free idxStr using sqlite3_free() if true */
7143
  int orderByConsumed;       /* True if output is already ordered */
7144
  double estimatedCost;           /* Estimated cost of using this index */
7145
  /* Fields below are only available in SQLite 3.8.2 and later */
7146
  sqlite3_int64 estimatedRows;    /* Estimated number of rows returned */
7147
  /* Fields below are only available in SQLite 3.9.0 and later */
7148
  int idxFlags;              /* Mask of SQLITE_INDEX_SCAN_* flags */
7149
  /* Fields below are only available in SQLite 3.10.0 and later */
7150
  sqlite3_uint64 colUsed;    /* Input: Mask of columns used by statement */
7151
};
7152
7153
/*
7154
** CAPI3REF: Virtual Table Scan Flags
7155
**
7156
** Virtual table implementations are allowed to set the
7157
** [sqlite3_index_info].idxFlags field to some combination of
7158
** these bits.
7159
*/
7160
#define SQLITE_INDEX_SCAN_UNIQUE      1     /* Scan visits at most 1 row */
7161
7162
/*
7163
** CAPI3REF: Virtual Table Constraint Operator Codes
7164
**
7165
** These macros define the allowed values for the
7166
** [sqlite3_index_info].aConstraint[].op field.  Each value represents
7167
** an operator that is part of a constraint term in the WHERE clause of
7168
** a query that uses a [virtual table].
7169
**
7170
** ^The left-hand operand of the operator is given by the corresponding
7171
** aConstraint[].iColumn field.  ^An iColumn of -1 indicates the left-hand
7172
** operand is the rowid.
7173
** The SQLITE_INDEX_CONSTRAINT_LIMIT and SQLITE_INDEX_CONSTRAINT_OFFSET
7174
** operators have no left-hand operand, and so for those operators the
7175
** corresponding aConstraint[].iColumn is meaningless and should not be
7176
** used.
7177
**
7178
** All operator values from SQLITE_INDEX_CONSTRAINT_FUNCTION through
7179
** value 255 are reserved to represent functions that are overloaded
7180
** by the [xFindFunction|xFindFunction method] of the virtual table
7181
** implementation.
7182
**
7183
** The right-hand operands for each constraint might be accessible using
7184
** the [sqlite3_vtab_rhs_value()] interface.  Usually the right-hand
7185
** operand is only available if it appears as a single constant literal
7186
** in the input SQL.  If the right-hand operand is another column or an
7187
** expression (even a constant expression) or a parameter, then the
7188
** sqlite3_vtab_rhs_value() probably will not be able to extract it.
7189
** ^The SQLITE_INDEX_CONSTRAINT_ISNULL and
7190
** SQLITE_INDEX_CONSTRAINT_ISNOTNULL operators have no right-hand operand
7191
** and hence calls to sqlite3_vtab_rhs_value() for those operators will
7192
** always return SQLITE_NOTFOUND.
7193
**
7194
** The collating sequence to be used for comparison can be found using
7195
** the [sqlite3_vtab_collation()] interface.  For most real-world virtual
7196
** tables, the collating sequence of constraints does not matter (for example
7197
** because the constraints are numeric) and so the sqlite3_vtab_collation()
7198
** interface is no commonly needed.
7199
*/
7200
#define SQLITE_INDEX_CONSTRAINT_EQ          2
7201
#define SQLITE_INDEX_CONSTRAINT_GT          4
7202
#define SQLITE_INDEX_CONSTRAINT_LE          8
7203
#define SQLITE_INDEX_CONSTRAINT_LT         16
7204
#define SQLITE_INDEX_CONSTRAINT_GE         32
7205
#define SQLITE_INDEX_CONSTRAINT_MATCH      64
7206
#define SQLITE_INDEX_CONSTRAINT_LIKE       65
7207
#define SQLITE_INDEX_CONSTRAINT_GLOB       66
7208
#define SQLITE_INDEX_CONSTRAINT_REGEXP     67
7209
#define SQLITE_INDEX_CONSTRAINT_NE         68
7210
#define SQLITE_INDEX_CONSTRAINT_ISNOT      69
7211
#define SQLITE_INDEX_CONSTRAINT_ISNOTNULL  70
7212
#define SQLITE_INDEX_CONSTRAINT_ISNULL     71
7213
#define SQLITE_INDEX_CONSTRAINT_IS         72
7214
#define SQLITE_INDEX_CONSTRAINT_LIMIT      73
7215
#define SQLITE_INDEX_CONSTRAINT_OFFSET     74
7216
#define SQLITE_INDEX_CONSTRAINT_FUNCTION  150
7217
7218
/*
7219
** CAPI3REF: Register A Virtual Table Implementation
7220
** METHOD: sqlite3
7221
**
7222
** ^These routines are used to register a new [virtual table module] name.
7223
** ^Module names must be registered before
7224
** creating a new [virtual table] using the module and before using a
7225
** preexisting [virtual table] for the module.
7226
**
7227
** ^The module name is registered on the [database connection] specified
7228
** by the first parameter.  ^The name of the module is given by the
7229
** second parameter.  ^The third parameter is a pointer to
7230
** the implementation of the [virtual table module].   ^The fourth
7231
** parameter is an arbitrary client data pointer that is passed through
7232
** into the [xCreate] and [xConnect] methods of the virtual table module
7233
** when a new virtual table is be being created or reinitialized.
7234
**
7235
** ^The sqlite3_create_module_v2() interface has a fifth parameter which
7236
** is a pointer to a destructor for the pClientData.  ^SQLite will
7237
** invoke the destructor function (if it is not NULL) when SQLite
7238
** no longer needs the pClientData pointer.  ^The destructor will also
7239
** be invoked if the call to sqlite3_create_module_v2() fails.
7240
** ^The sqlite3_create_module()
7241
** interface is equivalent to sqlite3_create_module_v2() with a NULL
7242
** destructor.
7243
**
7244
** ^If the third parameter (the pointer to the sqlite3_module object) is
7245
** NULL then no new module is created and any existing modules with the
7246
** same name are dropped.
7247
**
7248
** See also: [sqlite3_drop_modules()]
7249
*/
7250
SQLITE_API int sqlite3_create_module(
7251
  sqlite3 *db,               /* SQLite connection to register module with */
7252
  const char *zName,         /* Name of the module */
7253
  const sqlite3_module *p,   /* Methods for the module */
7254
  void *pClientData          /* Client data for xCreate/xConnect */
7255
);
7256
SQLITE_API int sqlite3_create_module_v2(
7257
  sqlite3 *db,               /* SQLite connection to register module with */
7258
  const char *zName,         /* Name of the module */
7259
  const sqlite3_module *p,   /* Methods for the module */
7260
  void *pClientData,         /* Client data for xCreate/xConnect */
7261
  void(*xDestroy)(void*)     /* Module destructor function */
7262
);
7263
7264
/*
7265
** CAPI3REF: Remove Unnecessary Virtual Table Implementations
7266
** METHOD: sqlite3
7267
**
7268
** ^The sqlite3_drop_modules(D,L) interface removes all virtual
7269
** table modules from database connection D except those named on list L.
7270
** The L parameter must be either NULL or a pointer to an array of pointers
7271
** to strings where the array is terminated by a single NULL pointer.
7272
** ^If the L parameter is NULL, then all virtual table modules are removed.
7273
**
7274
** See also: [sqlite3_create_module()]
7275
*/
7276
SQLITE_API int sqlite3_drop_modules(
7277
  sqlite3 *db,                /* Remove modules from this connection */
7278
  const char **azKeep         /* Except, do not remove the ones named here */
7279
);
7280
7281
/*
7282
** CAPI3REF: Virtual Table Instance Object
7283
** KEYWORDS: sqlite3_vtab
7284
**
7285
** Every [virtual table module] implementation uses a subclass
7286
** of this object to describe a particular instance
7287
** of the [virtual table].  Each subclass will
7288
** be tailored to the specific needs of the module implementation.
7289
** The purpose of this superclass is to define certain fields that are
7290
** common to all module implementations.
7291
**
7292
** ^Virtual tables methods can set an error message by assigning a
7293
** string obtained from [sqlite3_mprintf()] to zErrMsg.  The method should
7294
** take care that any prior string is freed by a call to [sqlite3_free()]
7295
** prior to assigning a new string to zErrMsg.  ^After the error message
7296
** is delivered up to the client application, the string will be automatically
7297
** freed by sqlite3_free() and the zErrMsg field will be zeroed.
7298
*/
7299
struct sqlite3_vtab {
7300
  const sqlite3_module *pModule;  /* The module for this virtual table */
7301
  int nRef;                       /* Number of open cursors */
7302
  char *zErrMsg;                  /* Error message from sqlite3_mprintf() */
7303
  /* Virtual table implementations will typically add additional fields */
7304
};
7305
7306
/*
7307
** CAPI3REF: Virtual Table Cursor Object
7308
** KEYWORDS: sqlite3_vtab_cursor {virtual table cursor}
7309
**
7310
** Every [virtual table module] implementation uses a subclass of the
7311
** following structure to describe cursors that point into the
7312
** [virtual table] and are used
7313
** to loop through the virtual table.  Cursors are created using the
7314
** [sqlite3_module.xOpen | xOpen] method of the module and are destroyed
7315
** by the [sqlite3_module.xClose | xClose] method.  Cursors are used
7316
** by the [xFilter], [xNext], [xEof], [xColumn], and [xRowid] methods
7317
** of the module.  Each module implementation will define
7318
** the content of a cursor structure to suit its own needs.
7319
**
7320
** This superclass exists in order to define fields of the cursor that
7321
** are common to all implementations.
7322
*/
7323
struct sqlite3_vtab_cursor {
7324
  sqlite3_vtab *pVtab;      /* Virtual table of this cursor */
7325
  /* Virtual table implementations will typically add additional fields */
7326
};
7327
7328
/*
7329
** CAPI3REF: Declare The Schema Of A Virtual Table
7330
**
7331
** ^The [xCreate] and [xConnect] methods of a
7332
** [virtual table module] call this interface
7333
** to declare the format (the names and datatypes of the columns) of
7334
** the virtual tables they implement.
7335
*/
7336
SQLITE_API int sqlite3_declare_vtab(sqlite3*, const char *zSQL);
7337
7338
/*
7339
** CAPI3REF: Overload A Function For A Virtual Table
7340
** METHOD: sqlite3
7341
**
7342
** ^(Virtual tables can provide alternative implementations of functions
7343
** using the [xFindFunction] method of the [virtual table module].
7344
** But global versions of those functions
7345
** must exist in order to be overloaded.)^
7346
**
7347
** ^(This API makes sure a global version of a function with a particular
7348
** name and number of parameters exists.  If no such function exists
7349
** before this API is called, a new function is created.)^  ^The implementation
7350
** of the new function always causes an exception to be thrown.  So
7351
** the new function is not good for anything by itself.  Its only
7352
** purpose is to be a placeholder function that can be overloaded
7353
** by a [virtual table].
7354
*/
7355
SQLITE_API int sqlite3_overload_function(sqlite3*, const char *zFuncName, int nArg);
7356
7357
/*
7358
** The interface to the virtual-table mechanism defined above (back up
7359
** to a comment remarkably similar to this one) is currently considered
7360
** to be experimental.  The interface might change in incompatible ways.
7361
** If this is a problem for you, do not use the interface at this time.
7362
**
7363
** When the virtual-table mechanism stabilizes, we will declare the
7364
** interface fixed, support it indefinitely, and remove this comment.
7365
*/
7366
7367
/*
7368
** CAPI3REF: A Handle To An Open BLOB
7369
** KEYWORDS: {BLOB handle} {BLOB handles}
7370
**
7371
** An instance of this object represents an open BLOB on which
7372
** [sqlite3_blob_open | incremental BLOB I/O] can be performed.
7373
** ^Objects of this type are created by [sqlite3_blob_open()]
7374
** and destroyed by [sqlite3_blob_close()].
7375
** ^The [sqlite3_blob_read()] and [sqlite3_blob_write()] interfaces
7376
** can be used to read or write small subsections of the BLOB.
7377
** ^The [sqlite3_blob_bytes()] interface returns the size of the BLOB in bytes.
7378
*/
7379
typedef struct sqlite3_blob sqlite3_blob;
7380
7381
/*
7382
** CAPI3REF: Open A BLOB For Incremental I/O
7383
** METHOD: sqlite3
7384
** CONSTRUCTOR: sqlite3_blob
7385
**
7386
** ^(This interfaces opens a [BLOB handle | handle] to the BLOB located
7387
** in row iRow, column zColumn, table zTable in database zDb;
7388
** in other words, the same BLOB that would be selected by:
7389
**
7390
** <pre>
7391
**     SELECT zColumn FROM zDb.zTable WHERE [rowid] = iRow;
7392
** </pre>)^
7393
**
7394
** ^(Parameter zDb is not the filename that contains the database, but
7395
** rather the symbolic name of the database. For attached databases, this is
7396
** the name that appears after the AS keyword in the [ATTACH] statement.
7397
** For the main database file, the database name is "main". For TEMP
7398
** tables, the database name is "temp".)^
7399
**
7400
** ^If the flags parameter is non-zero, then the BLOB is opened for read
7401
** and write access. ^If the flags parameter is zero, the BLOB is opened for
7402
** read-only access.
7403
**
7404
** ^(On success, [SQLITE_OK] is returned and the new [BLOB handle] is stored
7405
** in *ppBlob. Otherwise an [error code] is returned and, unless the error
7406
** code is SQLITE_MISUSE, *ppBlob is set to NULL.)^ ^This means that, provided
7407
** the API is not misused, it is always safe to call [sqlite3_blob_close()]
7408
** on *ppBlob after this function it returns.
7409
**
7410
** This function fails with SQLITE_ERROR if any of the following are true:
7411
** <ul>
7412
**   <li> ^(Database zDb does not exist)^,
7413
**   <li> ^(Table zTable does not exist within database zDb)^,
7414
**   <li> ^(Table zTable is a WITHOUT ROWID table)^,
7415
**   <li> ^(Column zColumn does not exist)^,
7416
**   <li> ^(Row iRow is not present in the table)^,
7417
**   <li> ^(The specified column of row iRow contains a value that is not
7418
**         a TEXT or BLOB value)^,
7419
**   <li> ^(Column zColumn is part of an index, PRIMARY KEY or UNIQUE
7420
**         constraint and the blob is being opened for read/write access)^,
7421
**   <li> ^([foreign key constraints | Foreign key constraints] are enabled,
7422
**         column zColumn is part of a [child key] definition and the blob is
7423
**         being opened for read/write access)^.
7424
** </ul>
7425
**
7426
** ^Unless it returns SQLITE_MISUSE, this function sets the
7427
** [database connection] error code and message accessible via
7428
** [sqlite3_errcode()] and [sqlite3_errmsg()] and related functions.
7429
**
7430
** A BLOB referenced by sqlite3_blob_open() may be read using the
7431
** [sqlite3_blob_read()] interface and modified by using
7432
** [sqlite3_blob_write()].  The [BLOB handle] can be moved to a
7433
** different row of the same table using the [sqlite3_blob_reopen()]
7434
** interface.  However, the column, table, or database of a [BLOB handle]
7435
** cannot be changed after the [BLOB handle] is opened.
7436
**
7437
** ^(If the row that a BLOB handle points to is modified by an
7438
** [UPDATE], [DELETE], or by [ON CONFLICT] side-effects
7439
** then the BLOB handle is marked as "expired".
7440
** This is true if any column of the row is changed, even a column
7441
** other than the one the BLOB handle is open on.)^
7442
** ^Calls to [sqlite3_blob_read()] and [sqlite3_blob_write()] for
7443
** an expired BLOB handle fail with a return code of [SQLITE_ABORT].
7444
** ^(Changes written into a BLOB prior to the BLOB expiring are not
7445
** rolled back by the expiration of the BLOB.  Such changes will eventually
7446
** commit if the transaction continues to completion.)^
7447
**
7448
** ^Use the [sqlite3_blob_bytes()] interface to determine the size of
7449
** the opened blob.  ^The size of a blob may not be changed by this
7450
** interface.  Use the [UPDATE] SQL command to change the size of a
7451
** blob.
7452
**
7453
** ^The [sqlite3_bind_zeroblob()] and [sqlite3_result_zeroblob()] interfaces
7454
** and the built-in [zeroblob] SQL function may be used to create a
7455
** zero-filled blob to read or write using the incremental-blob interface.
7456
**
7457
** To avoid a resource leak, every open [BLOB handle] should eventually
7458
** be released by a call to [sqlite3_blob_close()].
7459
**
7460
** See also: [sqlite3_blob_close()],
7461
** [sqlite3_blob_reopen()], [sqlite3_blob_read()],
7462
** [sqlite3_blob_bytes()], [sqlite3_blob_write()].
7463
*/
7464
SQLITE_API int sqlite3_blob_open(
7465
  sqlite3*,
7466
  const char *zDb,
7467
  const char *zTable,
7468
  const char *zColumn,
7469
  sqlite3_int64 iRow,
7470
  int flags,
7471
  sqlite3_blob **ppBlob
7472
);
7473
7474
/*
7475
** CAPI3REF: Move a BLOB Handle to a New Row
7476
** METHOD: sqlite3_blob
7477
**
7478
** ^This function is used to move an existing [BLOB handle] so that it points
7479
** to a different row of the same database table. ^The new row is identified
7480
** by the rowid value passed as the second argument. Only the row can be
7481
** changed. ^The database, table and column on which the blob handle is open
7482
** remain the same. Moving an existing [BLOB handle] to a new row is
7483
** faster than closing the existing handle and opening a new one.
7484
**
7485
** ^(The new row must meet the same criteria as for [sqlite3_blob_open()] -
7486
** it must exist and there must be either a blob or text value stored in
7487
** the nominated column.)^ ^If the new row is not present in the table, or if
7488
** it does not contain a blob or text value, or if another error occurs, an
7489
** SQLite error code is returned and the blob handle is considered aborted.
7490
** ^All subsequent calls to [sqlite3_blob_read()], [sqlite3_blob_write()] or
7491
** [sqlite3_blob_reopen()] on an aborted blob handle immediately return
7492
** SQLITE_ABORT. ^Calling [sqlite3_blob_bytes()] on an aborted blob handle
7493
** always returns zero.
7494
**
7495
** ^This function sets the database handle error code and message.
7496
*/
7497
SQLITE_API int sqlite3_blob_reopen(sqlite3_blob *, sqlite3_int64);
7498
7499
/*
7500
** CAPI3REF: Close A BLOB Handle
7501
** DESTRUCTOR: sqlite3_blob
7502
**
7503
** ^This function closes an open [BLOB handle]. ^(The BLOB handle is closed
7504
** unconditionally.  Even if this routine returns an error code, the
7505
** handle is still closed.)^
7506
**
7507
** ^If the blob handle being closed was opened for read-write access, and if
7508
** the database is in auto-commit mode and there are no other open read-write
7509
** blob handles or active write statements, the current transaction is
7510
** committed. ^If an error occurs while committing the transaction, an error
7511
** code is returned and the transaction rolled back.
7512
**
7513
** Calling this function with an argument that is not a NULL pointer or an
7514
** open blob handle results in undefined behaviour. ^Calling this routine
7515
** with a null pointer (such as would be returned by a failed call to
7516
** [sqlite3_blob_open()]) is a harmless no-op. ^Otherwise, if this function
7517
** is passed a valid open blob handle, the values returned by the
7518
** sqlite3_errcode() and sqlite3_errmsg() functions are set before returning.
7519
*/
7520
SQLITE_API int sqlite3_blob_close(sqlite3_blob *);
7521
7522
/*
7523
** CAPI3REF: Return The Size Of An Open BLOB
7524
** METHOD: sqlite3_blob
7525
**
7526
** ^Returns the size in bytes of the BLOB accessible via the
7527
** successfully opened [BLOB handle] in its only argument.  ^The
7528
** incremental blob I/O routines can only read or overwriting existing
7529
** blob content; they cannot change the size of a blob.
7530
**
7531
** This routine only works on a [BLOB handle] which has been created
7532
** by a prior successful call to [sqlite3_blob_open()] and which has not
7533
** been closed by [sqlite3_blob_close()].  Passing any other pointer in
7534
** to this routine results in undefined and probably undesirable behavior.
7535
*/
7536
SQLITE_API int sqlite3_blob_bytes(sqlite3_blob *);
7537
7538
/*
7539
** CAPI3REF: Read Data From A BLOB Incrementally
7540
** METHOD: sqlite3_blob
7541
**
7542
** ^(This function is used to read data from an open [BLOB handle] into a
7543
** caller-supplied buffer. N bytes of data are copied into buffer Z
7544
** from the open BLOB, starting at offset iOffset.)^
7545
**
7546
** ^If offset iOffset is less than N bytes from the end of the BLOB,
7547
** [SQLITE_ERROR] is returned and no data is read.  ^If N or iOffset is
7548
** less than zero, [SQLITE_ERROR] is returned and no data is read.
7549
** ^The size of the blob (and hence the maximum value of N+iOffset)
7550
** can be determined using the [sqlite3_blob_bytes()] interface.
7551
**
7552
** ^An attempt to read from an expired [BLOB handle] fails with an
7553
** error code of [SQLITE_ABORT].
7554
**
7555
** ^(On success, sqlite3_blob_read() returns SQLITE_OK.
7556
** Otherwise, an [error code] or an [extended error code] is returned.)^
7557
**
7558
** This routine only works on a [BLOB handle] which has been created
7559
** by a prior successful call to [sqlite3_blob_open()] and which has not
7560
** been closed by [sqlite3_blob_close()].  Passing any other pointer in
7561
** to this routine results in undefined and probably undesirable behavior.
7562
**
7563
** See also: [sqlite3_blob_write()].
7564
*/
7565
SQLITE_API int sqlite3_blob_read(sqlite3_blob *, void *Z, int N, int iOffset);
7566
7567
/*
7568
** CAPI3REF: Write Data Into A BLOB Incrementally
7569
** METHOD: sqlite3_blob
7570
**
7571
** ^(This function is used to write data into an open [BLOB handle] from a
7572
** caller-supplied buffer. N bytes of data are copied from the buffer Z
7573
** into the open BLOB, starting at offset iOffset.)^
7574
**
7575
** ^(On success, sqlite3_blob_write() returns SQLITE_OK.
7576
** Otherwise, an  [error code] or an [extended error code] is returned.)^
7577
** ^Unless SQLITE_MISUSE is returned, this function sets the
7578
** [database connection] error code and message accessible via
7579
** [sqlite3_errcode()] and [sqlite3_errmsg()] and related functions.
7580
**
7581
** ^If the [BLOB handle] passed as the first argument was not opened for
7582
** writing (the flags parameter to [sqlite3_blob_open()] was zero),
7583
** this function returns [SQLITE_READONLY].
7584
**
7585
** This function may only modify the contents of the BLOB; it is
7586
** not possible to increase the size of a BLOB using this API.
7587
** ^If offset iOffset is less than N bytes from the end of the BLOB,
7588
** [SQLITE_ERROR] is returned and no data is written. The size of the
7589
** BLOB (and hence the maximum value of N+iOffset) can be determined
7590
** using the [sqlite3_blob_bytes()] interface. ^If N or iOffset are less
7591
** than zero [SQLITE_ERROR] is returned and no data is written.
7592
**
7593
** ^An attempt to write to an expired [BLOB handle] fails with an
7594
** error code of [SQLITE_ABORT].  ^Writes to the BLOB that occurred
7595
** before the [BLOB handle] expired are not rolled back by the
7596
** expiration of the handle, though of course those changes might
7597
** have been overwritten by the statement that expired the BLOB handle
7598
** or by other independent statements.
7599
**
7600
** This routine only works on a [BLOB handle] which has been created
7601
** by a prior successful call to [sqlite3_blob_open()] and which has not
7602
** been closed by [sqlite3_blob_close()].  Passing any other pointer in
7603
** to this routine results in undefined and probably undesirable behavior.
7604
**
7605
** See also: [sqlite3_blob_read()].
7606
*/
7607
SQLITE_API int sqlite3_blob_write(sqlite3_blob *, const void *z, int n, int iOffset);
7608
7609
/*
7610
** CAPI3REF: Virtual File System Objects
7611
**
7612
** A virtual filesystem (VFS) is an [sqlite3_vfs] object
7613
** that SQLite uses to interact
7614
** with the underlying operating system.  Most SQLite builds come with a
7615
** single default VFS that is appropriate for the host computer.
7616
** New VFSes can be registered and existing VFSes can be unregistered.
7617
** The following interfaces are provided.
7618
**
7619
** ^The sqlite3_vfs_find() interface returns a pointer to a VFS given its name.
7620
** ^Names are case sensitive.
7621
** ^Names are zero-terminated UTF-8 strings.
7622
** ^If there is no match, a NULL pointer is returned.
7623
** ^If zVfsName is NULL then the default VFS is returned.
7624
**
7625
** ^New VFSes are registered with sqlite3_vfs_register().
7626
** ^Each new VFS becomes the default VFS if the makeDflt flag is set.
7627
** ^The same VFS can be registered multiple times without injury.
7628
** ^To make an existing VFS into the default VFS, register it again
7629
** with the makeDflt flag set.  If two different VFSes with the
7630
** same name are registered, the behavior is undefined.  If a
7631
** VFS is registered with a name that is NULL or an empty string,
7632
** then the behavior is undefined.
7633
**
7634
** ^Unregister a VFS with the sqlite3_vfs_unregister() interface.
7635
** ^(If the default VFS is unregistered, another VFS is chosen as
7636
** the default.  The choice for the new VFS is arbitrary.)^
7637
*/
7638
SQLITE_API sqlite3_vfs *sqlite3_vfs_find(const char *zVfsName);
7639
SQLITE_API int sqlite3_vfs_register(sqlite3_vfs*, int makeDflt);
7640
SQLITE_API int sqlite3_vfs_unregister(sqlite3_vfs*);
7641
7642
/*
7643
** CAPI3REF: Mutexes
7644
**
7645
** The SQLite core uses these routines for thread
7646
** synchronization. Though they are intended for internal
7647
** use by SQLite, code that links against SQLite is
7648
** permitted to use any of these routines.
7649
**
7650
** The SQLite source code contains multiple implementations
7651
** of these mutex routines.  An appropriate implementation
7652
** is selected automatically at compile-time.  The following
7653
** implementations are available in the SQLite core:
7654
**
7655
** <ul>
7656
** <li>   SQLITE_MUTEX_PTHREADS
7657
** <li>   SQLITE_MUTEX_W32
7658
** <li>   SQLITE_MUTEX_NOOP
7659
** </ul>
7660
**
7661
** The SQLITE_MUTEX_NOOP implementation is a set of routines
7662
** that does no real locking and is appropriate for use in
7663
** a single-threaded application.  The SQLITE_MUTEX_PTHREADS and
7664
** SQLITE_MUTEX_W32 implementations are appropriate for use on Unix
7665
** and Windows.
7666
**
7667
** If SQLite is compiled with the SQLITE_MUTEX_APPDEF preprocessor
7668
** macro defined (with "-DSQLITE_MUTEX_APPDEF=1"), then no mutex
7669
** implementation is included with the library. In this case the
7670
** application must supply a custom mutex implementation using the
7671
** [SQLITE_CONFIG_MUTEX] option of the sqlite3_config() function
7672
** before calling sqlite3_initialize() or any other public sqlite3_
7673
** function that calls sqlite3_initialize().
7674
**
7675
** ^The sqlite3_mutex_alloc() routine allocates a new
7676
** mutex and returns a pointer to it. ^The sqlite3_mutex_alloc()
7677
** routine returns NULL if it is unable to allocate the requested
7678
** mutex.  The argument to sqlite3_mutex_alloc() must one of these
7679
** integer constants:
7680
**
7681
** <ul>
7682
** <li>  SQLITE_MUTEX_FAST
7683
** <li>  SQLITE_MUTEX_RECURSIVE
7684
** <li>  SQLITE_MUTEX_STATIC_MAIN
7685
** <li>  SQLITE_MUTEX_STATIC_MEM
7686
** <li>  SQLITE_MUTEX_STATIC_OPEN
7687
** <li>  SQLITE_MUTEX_STATIC_PRNG
7688
** <li>  SQLITE_MUTEX_STATIC_LRU
7689
** <li>  SQLITE_MUTEX_STATIC_PMEM
7690
** <li>  SQLITE_MUTEX_STATIC_APP1
7691
** <li>  SQLITE_MUTEX_STATIC_APP2
7692
** <li>  SQLITE_MUTEX_STATIC_APP3
7693
** <li>  SQLITE_MUTEX_STATIC_VFS1
7694
** <li>  SQLITE_MUTEX_STATIC_VFS2
7695
** <li>  SQLITE_MUTEX_STATIC_VFS3
7696
** </ul>
7697
**
7698
** ^The first two constants (SQLITE_MUTEX_FAST and SQLITE_MUTEX_RECURSIVE)
7699
** cause sqlite3_mutex_alloc() to create
7700
** a new mutex.  ^The new mutex is recursive when SQLITE_MUTEX_RECURSIVE
7701
** is used but not necessarily so when SQLITE_MUTEX_FAST is used.
7702
** The mutex implementation does not need to make a distinction
7703
** between SQLITE_MUTEX_RECURSIVE and SQLITE_MUTEX_FAST if it does
7704
** not want to.  SQLite will only request a recursive mutex in
7705
** cases where it really needs one.  If a faster non-recursive mutex
7706
** implementation is available on the host platform, the mutex subsystem
7707
** might return such a mutex in response to SQLITE_MUTEX_FAST.
7708
**
7709
** ^The other allowed parameters to sqlite3_mutex_alloc() (anything other
7710
** than SQLITE_MUTEX_FAST and SQLITE_MUTEX_RECURSIVE) each return
7711
** a pointer to a static preexisting mutex.  ^Nine static mutexes are
7712
** used by the current version of SQLite.  Future versions of SQLite
7713
** may add additional static mutexes.  Static mutexes are for internal
7714
** use by SQLite only.  Applications that use SQLite mutexes should
7715
** use only the dynamic mutexes returned by SQLITE_MUTEX_FAST or
7716
** SQLITE_MUTEX_RECURSIVE.
7717
**
7718
** ^Note that if one of the dynamic mutex parameters (SQLITE_MUTEX_FAST
7719
** or SQLITE_MUTEX_RECURSIVE) is used then sqlite3_mutex_alloc()
7720
** returns a different mutex on every call.  ^For the static
7721
** mutex types, the same mutex is returned on every call that has
7722
** the same type number.
7723
**
7724
** ^The sqlite3_mutex_free() routine deallocates a previously
7725
** allocated dynamic mutex.  Attempting to deallocate a static
7726
** mutex results in undefined behavior.
7727
**
7728
** ^The sqlite3_mutex_enter() and sqlite3_mutex_try() routines attempt
7729
** to enter a mutex.  ^If another thread is already within the mutex,
7730
** sqlite3_mutex_enter() will block and sqlite3_mutex_try() will return
7731
** SQLITE_BUSY.  ^The sqlite3_mutex_try() interface returns [SQLITE_OK]
7732
** upon successful entry.  ^(Mutexes created using
7733
** SQLITE_MUTEX_RECURSIVE can be entered multiple times by the same thread.
7734
** In such cases, the
7735
** mutex must be exited an equal number of times before another thread
7736
** can enter.)^  If the same thread tries to enter any mutex other
7737
** than an SQLITE_MUTEX_RECURSIVE more than once, the behavior is undefined.
7738
**
7739
** ^(Some systems (for example, Windows 95) do not support the operation
7740
** implemented by sqlite3_mutex_try().  On those systems, sqlite3_mutex_try()
7741
** will always return SQLITE_BUSY. The SQLite core only ever uses
7742
** sqlite3_mutex_try() as an optimization so this is acceptable
7743
** behavior.)^
7744
**
7745
** ^The sqlite3_mutex_leave() routine exits a mutex that was
7746
** previously entered by the same thread.   The behavior
7747
** is undefined if the mutex is not currently entered by the
7748
** calling thread or is not currently allocated.
7749
**
7750
** ^If the argument to sqlite3_mutex_enter(), sqlite3_mutex_try(), or
7751
** sqlite3_mutex_leave() is a NULL pointer, then all three routines
7752
** behave as no-ops.
7753
**
7754
** See also: [sqlite3_mutex_held()] and [sqlite3_mutex_notheld()].
7755
*/
7756
SQLITE_API sqlite3_mutex *sqlite3_mutex_alloc(int);
7757
SQLITE_API void sqlite3_mutex_free(sqlite3_mutex*);
7758
SQLITE_API void sqlite3_mutex_enter(sqlite3_mutex*);
7759
SQLITE_API int sqlite3_mutex_try(sqlite3_mutex*);
7760
SQLITE_API void sqlite3_mutex_leave(sqlite3_mutex*);
7761
7762
/*
7763
** CAPI3REF: Mutex Methods Object
7764
**
7765
** An instance of this structure defines the low-level routines
7766
** used to allocate and use mutexes.
7767
**
7768
** Usually, the default mutex implementations provided by SQLite are
7769
** sufficient, however the application has the option of substituting a custom
7770
** implementation for specialized deployments or systems for which SQLite
7771
** does not provide a suitable implementation. In this case, the application
7772
** creates and populates an instance of this structure to pass
7773
** to sqlite3_config() along with the [SQLITE_CONFIG_MUTEX] option.
7774
** Additionally, an instance of this structure can be used as an
7775
** output variable when querying the system for the current mutex
7776
** implementation, using the [SQLITE_CONFIG_GETMUTEX] option.
7777
**
7778
** ^The xMutexInit method defined by this structure is invoked as
7779
** part of system initialization by the sqlite3_initialize() function.
7780
** ^The xMutexInit routine is called by SQLite exactly once for each
7781
** effective call to [sqlite3_initialize()].
7782
**
7783
** ^The xMutexEnd method defined by this structure is invoked as
7784
** part of system shutdown by the sqlite3_shutdown() function. The
7785
** implementation of this method is expected to release all outstanding
7786
** resources obtained by the mutex methods implementation, especially
7787
** those obtained by the xMutexInit method.  ^The xMutexEnd()
7788
** interface is invoked exactly once for each call to [sqlite3_shutdown()].
7789
**
7790
** ^(The remaining seven methods defined by this structure (xMutexAlloc,
7791
** xMutexFree, xMutexEnter, xMutexTry, xMutexLeave, xMutexHeld and
7792
** xMutexNotheld) implement the following interfaces (respectively):
7793
**
7794
** <ul>
7795
**   <li>  [sqlite3_mutex_alloc()] </li>
7796
**   <li>  [sqlite3_mutex_free()] </li>
7797
**   <li>  [sqlite3_mutex_enter()] </li>
7798
**   <li>  [sqlite3_mutex_try()] </li>
7799
**   <li>  [sqlite3_mutex_leave()] </li>
7800
**   <li>  [sqlite3_mutex_held()] </li>
7801
**   <li>  [sqlite3_mutex_notheld()] </li>
7802
** </ul>)^
7803
**
7804
** The only difference is that the public sqlite3_XXX functions enumerated
7805
** above silently ignore any invocations that pass a NULL pointer instead
7806
** of a valid mutex handle. The implementations of the methods defined
7807
** by this structure are not required to handle this case. The results
7808
** of passing a NULL pointer instead of a valid mutex handle are undefined
7809
** (i.e. it is acceptable to provide an implementation that segfaults if
7810
** it is passed a NULL pointer).
7811
**
7812
** The xMutexInit() method must be threadsafe.  It must be harmless to
7813
** invoke xMutexInit() multiple times within the same process and without
7814
** intervening calls to xMutexEnd().  Second and subsequent calls to
7815
** xMutexInit() must be no-ops.
7816
**
7817
** xMutexInit() must not use SQLite memory allocation ([sqlite3_malloc()]
7818
** and its associates).  Similarly, xMutexAlloc() must not use SQLite memory
7819
** allocation for a static mutex.  ^However xMutexAlloc() may use SQLite
7820
** memory allocation for a fast or recursive mutex.
7821
**
7822
** ^SQLite will invoke the xMutexEnd() method when [sqlite3_shutdown()] is
7823
** called, but only if the prior call to xMutexInit returned SQLITE_OK.
7824
** If xMutexInit fails in any way, it is expected to clean up after itself
7825
** prior to returning.
7826
*/
7827
typedef struct sqlite3_mutex_methods sqlite3_mutex_methods;
7828
struct sqlite3_mutex_methods {
7829
  int (*xMutexInit)(void);
7830
  int (*xMutexEnd)(void);
7831
  sqlite3_mutex *(*xMutexAlloc)(int);
7832
  void (*xMutexFree)(sqlite3_mutex *);
7833
  void (*xMutexEnter)(sqlite3_mutex *);
7834
  int (*xMutexTry)(sqlite3_mutex *);
7835
  void (*xMutexLeave)(sqlite3_mutex *);
7836
  int (*xMutexHeld)(sqlite3_mutex *);
7837
  int (*xMutexNotheld)(sqlite3_mutex *);
7838
};
7839
7840
/*
7841
** CAPI3REF: Mutex Verification Routines
7842
**
7843
** The sqlite3_mutex_held() and sqlite3_mutex_notheld() routines
7844
** are intended for use inside assert() statements.  The SQLite core
7845
** never uses these routines except inside an assert() and applications
7846
** are advised to follow the lead of the core.  The SQLite core only
7847
** provides implementations for these routines when it is compiled
7848
** with the SQLITE_DEBUG flag.  External mutex implementations
7849
** are only required to provide these routines if SQLITE_DEBUG is
7850
** defined and if NDEBUG is not defined.
7851
**
7852
** These routines should return true if the mutex in their argument
7853
** is held or not held, respectively, by the calling thread.
7854
**
7855
** The implementation is not required to provide versions of these
7856
** routines that actually work. If the implementation does not provide working
7857
** versions of these routines, it should at least provide stubs that always
7858
** return true so that one does not get spurious assertion failures.
7859
**
7860
** If the argument to sqlite3_mutex_held() is a NULL pointer then
7861
** the routine should return 1.   This seems counter-intuitive since
7862
** clearly the mutex cannot be held if it does not exist.  But
7863
** the reason the mutex does not exist is because the build is not
7864
** using mutexes.  And we do not want the assert() containing the
7865
** call to sqlite3_mutex_held() to fail, so a non-zero return is
7866
** the appropriate thing to do.  The sqlite3_mutex_notheld()
7867
** interface should also return 1 when given a NULL pointer.
7868
*/
7869
#ifndef NDEBUG
7870
SQLITE_API int sqlite3_mutex_held(sqlite3_mutex*);
7871
SQLITE_API int sqlite3_mutex_notheld(sqlite3_mutex*);
7872
#endif
7873
7874
/*
7875
** CAPI3REF: Mutex Types
7876
**
7877
** The [sqlite3_mutex_alloc()] interface takes a single argument
7878
** which is one of these integer constants.
7879
**
7880
** The set of static mutexes may change from one SQLite release to the
7881
** next.  Applications that override the built-in mutex logic must be
7882
** prepared to accommodate additional static mutexes.
7883
*/
7884
#define SQLITE_MUTEX_FAST             0
7885
#define SQLITE_MUTEX_RECURSIVE        1
7886
#define SQLITE_MUTEX_STATIC_MAIN      2
7887
#define SQLITE_MUTEX_STATIC_MEM       3  /* sqlite3_malloc() */
7888
#define SQLITE_MUTEX_STATIC_MEM2      4  /* NOT USED */
7889
#define SQLITE_MUTEX_STATIC_OPEN      4  /* sqlite3BtreeOpen() */
7890
#define SQLITE_MUTEX_STATIC_PRNG      5  /* sqlite3_randomness() */
7891
#define SQLITE_MUTEX_STATIC_LRU       6  /* lru page list */
7892
#define SQLITE_MUTEX_STATIC_LRU2      7  /* NOT USED */
7893
#define SQLITE_MUTEX_STATIC_PMEM      7  /* sqlite3PageMalloc() */
7894
#define SQLITE_MUTEX_STATIC_APP1      8  /* For use by application */
7895
#define SQLITE_MUTEX_STATIC_APP2      9  /* For use by application */
7896
#define SQLITE_MUTEX_STATIC_APP3     10  /* For use by application */
7897
#define SQLITE_MUTEX_STATIC_VFS1     11  /* For use by built-in VFS */
7898
#define SQLITE_MUTEX_STATIC_VFS2     12  /* For use by extension VFS */
7899
#define SQLITE_MUTEX_STATIC_VFS3     13  /* For use by application VFS */
7900
7901
/* Legacy compatibility: */
7902
#define SQLITE_MUTEX_STATIC_MASTER    2
7903
7904
7905
/*
7906
** CAPI3REF: Retrieve the mutex for a database connection
7907
** METHOD: sqlite3
7908
**
7909
** ^This interface returns a pointer the [sqlite3_mutex] object that
7910
** serializes access to the [database connection] given in the argument
7911
** when the [threading mode] is Serialized.
7912
** ^If the [threading mode] is Single-thread or Multi-thread then this
7913
** routine returns a NULL pointer.
7914
*/
7915
SQLITE_API sqlite3_mutex *sqlite3_db_mutex(sqlite3*);
7916
7917
/*
7918
** CAPI3REF: Low-Level Control Of Database Files
7919
** METHOD: sqlite3
7920
** KEYWORDS: {file control}
7921
**
7922
** ^The [sqlite3_file_control()] interface makes a direct call to the
7923
** xFileControl method for the [sqlite3_io_methods] object associated
7924
** with a particular database identified by the second argument. ^The
7925
** name of the database is "main" for the main database or "temp" for the
7926
** TEMP database, or the name that appears after the AS keyword for
7927
** databases that are added using the [ATTACH] SQL command.
7928
** ^A NULL pointer can be used in place of "main" to refer to the
7929
** main database file.
7930
** ^The third and fourth parameters to this routine
7931
** are passed directly through to the second and third parameters of
7932
** the xFileControl method.  ^The return value of the xFileControl
7933
** method becomes the return value of this routine.
7934
**
7935
** A few opcodes for [sqlite3_file_control()] are handled directly
7936
** by the SQLite core and never invoke the
7937
** sqlite3_io_methods.xFileControl method.
7938
** ^The [SQLITE_FCNTL_FILE_POINTER] value for the op parameter causes
7939
** a pointer to the underlying [sqlite3_file] object to be written into
7940
** the space pointed to by the 4th parameter.  The
7941
** [SQLITE_FCNTL_JOURNAL_POINTER] works similarly except that it returns
7942
** the [sqlite3_file] object associated with the journal file instead of
7943
** the main database.  The [SQLITE_FCNTL_VFS_POINTER] opcode returns
7944
** a pointer to the underlying [sqlite3_vfs] object for the file.
7945
** The [SQLITE_FCNTL_DATA_VERSION] returns the data version counter
7946
** from the pager.
7947
**
7948
** ^If the second parameter (zDbName) does not match the name of any
7949
** open database file, then SQLITE_ERROR is returned.  ^This error
7950
** code is not remembered and will not be recalled by [sqlite3_errcode()]
7951
** or [sqlite3_errmsg()].  The underlying xFileControl method might
7952
** also return SQLITE_ERROR.  There is no way to distinguish between
7953
** an incorrect zDbName and an SQLITE_ERROR return from the underlying
7954
** xFileControl method.
7955
**
7956
** See also: [file control opcodes]
7957
*/
7958
SQLITE_API int sqlite3_file_control(sqlite3*, const char *zDbName, int op, void*);
7959
7960
/*
7961
** CAPI3REF: Testing Interface
7962
**
7963
** ^The sqlite3_test_control() interface is used to read out internal
7964
** state of SQLite and to inject faults into SQLite for testing
7965
** purposes.  ^The first parameter is an operation code that determines
7966
** the number, meaning, and operation of all subsequent parameters.
7967
**
7968
** This interface is not for use by applications.  It exists solely
7969
** for verifying the correct operation of the SQLite library.  Depending
7970
** on how the SQLite library is compiled, this interface might not exist.
7971
**
7972
** The details of the operation codes, their meanings, the parameters
7973
** they take, and what they do are all subject to change without notice.
7974
** Unlike most of the SQLite API, this function is not guaranteed to
7975
** operate consistently from one release to the next.
7976
*/
7977
SQLITE_API int sqlite3_test_control(int op, ...);
7978
7979
/*
7980
** CAPI3REF: Testing Interface Operation Codes
7981
**
7982
** These constants are the valid operation code parameters used
7983
** as the first argument to [sqlite3_test_control()].
7984
**
7985
** These parameters and their meanings are subject to change
7986
** without notice.  These values are for testing purposes only.
7987
** Applications should not use any of these parameters or the
7988
** [sqlite3_test_control()] interface.
7989
*/
7990
#define SQLITE_TESTCTRL_FIRST                    5
7991
#define SQLITE_TESTCTRL_PRNG_SAVE                5
7992
#define SQLITE_TESTCTRL_PRNG_RESTORE             6
7993
#define SQLITE_TESTCTRL_PRNG_RESET               7  /* NOT USED */
7994
#define SQLITE_TESTCTRL_BITVEC_TEST              8
7995
#define SQLITE_TESTCTRL_FAULT_INSTALL            9
7996
#define SQLITE_TESTCTRL_BENIGN_MALLOC_HOOKS     10
7997
#define SQLITE_TESTCTRL_PENDING_BYTE            11
7998
#define SQLITE_TESTCTRL_ASSERT                  12
7999
#define SQLITE_TESTCTRL_ALWAYS                  13
8000
#define SQLITE_TESTCTRL_RESERVE                 14  /* NOT USED */
8001
#define SQLITE_TESTCTRL_OPTIMIZATIONS           15
8002
#define SQLITE_TESTCTRL_ISKEYWORD               16  /* NOT USED */
8003
#define SQLITE_TESTCTRL_SCRATCHMALLOC           17  /* NOT USED */
8004
#define SQLITE_TESTCTRL_INTERNAL_FUNCTIONS      17
8005
#define SQLITE_TESTCTRL_LOCALTIME_FAULT         18
8006
#define SQLITE_TESTCTRL_EXPLAIN_STMT            19  /* NOT USED */
8007
#define SQLITE_TESTCTRL_ONCE_RESET_THRESHOLD    19
8008
#define SQLITE_TESTCTRL_NEVER_CORRUPT           20
8009
#define SQLITE_TESTCTRL_VDBE_COVERAGE           21
8010
#define SQLITE_TESTCTRL_BYTEORDER               22
8011
#define SQLITE_TESTCTRL_ISINIT                  23
8012
#define SQLITE_TESTCTRL_SORTER_MMAP             24
8013
#define SQLITE_TESTCTRL_IMPOSTER                25
8014
#define SQLITE_TESTCTRL_PARSER_COVERAGE         26
8015
#define SQLITE_TESTCTRL_RESULT_INTREAL          27
8016
#define SQLITE_TESTCTRL_PRNG_SEED               28
8017
#define SQLITE_TESTCTRL_EXTRA_SCHEMA_CHECKS     29
8018
#define SQLITE_TESTCTRL_SEEK_COUNT              30
8019
#define SQLITE_TESTCTRL_TRACEFLAGS              31
8020
#define SQLITE_TESTCTRL_TUNE                    32
8021
#define SQLITE_TESTCTRL_LOGEST                  33
8022
#define SQLITE_TESTCTRL_LAST                    33  /* Largest TESTCTRL */
8023
8024
/*
8025
** CAPI3REF: SQL Keyword Checking
8026
**
8027
** These routines provide access to the set of SQL language keywords
8028
** recognized by SQLite.  Applications can uses these routines to determine
8029
** whether or not a specific identifier needs to be escaped (for example,
8030
** by enclosing in double-quotes) so as not to confuse the parser.
8031
**
8032
** The sqlite3_keyword_count() interface returns the number of distinct
8033
** keywords understood by SQLite.
8034
**
8035
** The sqlite3_keyword_name(N,Z,L) interface finds the N-th keyword and
8036
** makes *Z point to that keyword expressed as UTF8 and writes the number
8037
** of bytes in the keyword into *L.  The string that *Z points to is not
8038
** zero-terminated.  The sqlite3_keyword_name(N,Z,L) routine returns
8039
** SQLITE_OK if N is within bounds and SQLITE_ERROR if not. If either Z
8040
** or L are NULL or invalid pointers then calls to
8041
** sqlite3_keyword_name(N,Z,L) result in undefined behavior.
8042
**
8043
** The sqlite3_keyword_check(Z,L) interface checks to see whether or not
8044
** the L-byte UTF8 identifier that Z points to is a keyword, returning non-zero
8045
** if it is and zero if not.
8046
**
8047
** The parser used by SQLite is forgiving.  It is often possible to use
8048
** a keyword as an identifier as long as such use does not result in a
8049
** parsing ambiguity.  For example, the statement
8050
** "CREATE TABLE BEGIN(REPLACE,PRAGMA,END);" is accepted by SQLite, and
8051
** creates a new table named "BEGIN" with three columns named
8052
** "REPLACE", "PRAGMA", and "END".  Nevertheless, best practice is to avoid
8053
** using keywords as identifiers.  Common techniques used to avoid keyword
8054
** name collisions include:
8055
** <ul>
8056
** <li> Put all identifier names inside double-quotes.  This is the official
8057
**      SQL way to escape identifier names.
8058
** <li> Put identifier names inside &#91;...&#93;.  This is not standard SQL,
8059
**      but it is what SQL Server does and so lots of programmers use this
8060
**      technique.
8061
** <li> Begin every identifier with the letter "Z" as no SQL keywords start
8062
**      with "Z".
8063
** <li> Include a digit somewhere in every identifier name.
8064
** </ul>
8065
**
8066
** Note that the number of keywords understood by SQLite can depend on
8067
** compile-time options.  For example, "VACUUM" is not a keyword if
8068
** SQLite is compiled with the [-DSQLITE_OMIT_VACUUM] option.  Also,
8069
** new keywords may be added to future releases of SQLite.
8070
*/
8071
SQLITE_API int sqlite3_keyword_count(void);
8072
SQLITE_API int sqlite3_keyword_name(int,const char**,int*);
8073
SQLITE_API int sqlite3_keyword_check(const char*,int);
8074
8075
/*
8076
** CAPI3REF: Dynamic String Object
8077
** KEYWORDS: {dynamic string}
8078
**
8079
** An instance of the sqlite3_str object contains a dynamically-sized
8080
** string under construction.
8081
**
8082
** The lifecycle of an sqlite3_str object is as follows:
8083
** <ol>
8084
** <li> ^The sqlite3_str object is created using [sqlite3_str_new()].
8085
** <li> ^Text is appended to the sqlite3_str object using various
8086
** methods, such as [sqlite3_str_appendf()].
8087
** <li> ^The sqlite3_str object is destroyed and the string it created
8088
** is returned using the [sqlite3_str_finish()] interface.
8089
** </ol>
8090
*/
8091
typedef struct sqlite3_str sqlite3_str;
8092
8093
/*
8094
** CAPI3REF: Create A New Dynamic String Object
8095
** CONSTRUCTOR: sqlite3_str
8096
**
8097
** ^The [sqlite3_str_new(D)] interface allocates and initializes
8098
** a new [sqlite3_str] object.  To avoid memory leaks, the object returned by
8099
** [sqlite3_str_new()] must be freed by a subsequent call to
8100
** [sqlite3_str_finish(X)].
8101
**
8102
** ^The [sqlite3_str_new(D)] interface always returns a pointer to a
8103
** valid [sqlite3_str] object, though in the event of an out-of-memory
8104
** error the returned object might be a special singleton that will
8105
** silently reject new text, always return SQLITE_NOMEM from
8106
** [sqlite3_str_errcode()], always return 0 for
8107
** [sqlite3_str_length()], and always return NULL from
8108
** [sqlite3_str_finish(X)].  It is always safe to use the value
8109
** returned by [sqlite3_str_new(D)] as the sqlite3_str parameter
8110
** to any of the other [sqlite3_str] methods.
8111
**
8112
** The D parameter to [sqlite3_str_new(D)] may be NULL.  If the
8113
** D parameter in [sqlite3_str_new(D)] is not NULL, then the maximum
8114
** length of the string contained in the [sqlite3_str] object will be
8115
** the value set for [sqlite3_limit](D,[SQLITE_LIMIT_LENGTH]) instead
8116
** of [SQLITE_MAX_LENGTH].
8117
*/
8118
SQLITE_API sqlite3_str *sqlite3_str_new(sqlite3*);
8119
8120
/*
8121
** CAPI3REF: Finalize A Dynamic String
8122
** DESTRUCTOR: sqlite3_str
8123
**
8124
** ^The [sqlite3_str_finish(X)] interface destroys the sqlite3_str object X
8125
** and returns a pointer to a memory buffer obtained from [sqlite3_malloc64()]
8126
** that contains the constructed string.  The calling application should
8127
** pass the returned value to [sqlite3_free()] to avoid a memory leak.
8128
** ^The [sqlite3_str_finish(X)] interface may return a NULL pointer if any
8129
** errors were encountered during construction of the string.  ^The
8130
** [sqlite3_str_finish(X)] interface will also return a NULL pointer if the
8131
** string in [sqlite3_str] object X is zero bytes long.
8132
*/
8133
SQLITE_API char *sqlite3_str_finish(sqlite3_str*);
8134
8135
/*
8136
** CAPI3REF: Add Content To A Dynamic String
8137
** METHOD: sqlite3_str
8138
**
8139
** These interfaces add content to an sqlite3_str object previously obtained
8140
** from [sqlite3_str_new()].
8141
**
8142
** ^The [sqlite3_str_appendf(X,F,...)] and
8143
** [sqlite3_str_vappendf(X,F,V)] interfaces uses the [built-in printf]
8144
** functionality of SQLite to append formatted text onto the end of
8145
** [sqlite3_str] object X.
8146
**
8147
** ^The [sqlite3_str_append(X,S,N)] method appends exactly N bytes from string S
8148
** onto the end of the [sqlite3_str] object X.  N must be non-negative.
8149
** S must contain at least N non-zero bytes of content.  To append a
8150
** zero-terminated string in its entirety, use the [sqlite3_str_appendall()]
8151
** method instead.
8152
**
8153
** ^The [sqlite3_str_appendall(X,S)] method appends the complete content of
8154
** zero-terminated string S onto the end of [sqlite3_str] object X.
8155
**
8156
** ^The [sqlite3_str_appendchar(X,N,C)] method appends N copies of the
8157
** single-byte character C onto the end of [sqlite3_str] object X.
8158
** ^This method can be used, for example, to add whitespace indentation.
8159
**
8160
** ^The [sqlite3_str_reset(X)] method resets the string under construction
8161
** inside [sqlite3_str] object X back to zero bytes in length.
8162
**
8163
** These methods do not return a result code.  ^If an error occurs, that fact
8164
** is recorded in the [sqlite3_str] object and can be recovered by a
8165
** subsequent call to [sqlite3_str_errcode(X)].
8166
*/
8167
SQLITE_API void sqlite3_str_appendf(sqlite3_str*, const char *zFormat, ...);
8168
SQLITE_API void sqlite3_str_vappendf(sqlite3_str*, const char *zFormat, va_list);
8169
SQLITE_API void sqlite3_str_append(sqlite3_str*, const char *zIn, int N);
8170
SQLITE_API void sqlite3_str_appendall(sqlite3_str*, const char *zIn);
8171
SQLITE_API void sqlite3_str_appendchar(sqlite3_str*, int N, char C);
8172
SQLITE_API void sqlite3_str_reset(sqlite3_str*);
8173
8174
/*
8175
** CAPI3REF: Status Of A Dynamic String
8176
** METHOD: sqlite3_str
8177
**
8178
** These interfaces return the current status of an [sqlite3_str] object.
8179
**
8180
** ^If any prior errors have occurred while constructing the dynamic string
8181
** in sqlite3_str X, then the [sqlite3_str_errcode(X)] method will return
8182
** an appropriate error code.  ^The [sqlite3_str_errcode(X)] method returns
8183
** [SQLITE_NOMEM] following any out-of-memory error, or
8184
** [SQLITE_TOOBIG] if the size of the dynamic string exceeds
8185
** [SQLITE_MAX_LENGTH], or [SQLITE_OK] if there have been no errors.
8186
**
8187
** ^The [sqlite3_str_length(X)] method returns the current length, in bytes,
8188
** of the dynamic string under construction in [sqlite3_str] object X.
8189
** ^The length returned by [sqlite3_str_length(X)] does not include the
8190
** zero-termination byte.
8191
**
8192
** ^The [sqlite3_str_value(X)] method returns a pointer to the current
8193
** content of the dynamic string under construction in X.  The value
8194
** returned by [sqlite3_str_value(X)] is managed by the sqlite3_str object X
8195
** and might be freed or altered by any subsequent method on the same
8196
** [sqlite3_str] object.  Applications must not used the pointer returned
8197
** [sqlite3_str_value(X)] after any subsequent method call on the same
8198
** object.  ^Applications may change the content of the string returned
8199
** by [sqlite3_str_value(X)] as long as they do not write into any bytes
8200
** outside the range of 0 to [sqlite3_str_length(X)] and do not read or
8201
** write any byte after any subsequent sqlite3_str method call.
8202
*/
8203
SQLITE_API int sqlite3_str_errcode(sqlite3_str*);
8204
SQLITE_API int sqlite3_str_length(sqlite3_str*);
8205
SQLITE_API char *sqlite3_str_value(sqlite3_str*);
8206
8207
/*
8208
** CAPI3REF: SQLite Runtime Status
8209
**
8210
** ^These interfaces are used to retrieve runtime status information
8211
** about the performance of SQLite, and optionally to reset various
8212
** highwater marks.  ^The first argument is an integer code for
8213
** the specific parameter to measure.  ^(Recognized integer codes
8214
** are of the form [status parameters | SQLITE_STATUS_...].)^
8215
** ^The current value of the parameter is returned into *pCurrent.
8216
** ^The highest recorded value is returned in *pHighwater.  ^If the
8217
** resetFlag is true, then the highest record value is reset after
8218
** *pHighwater is written.  ^(Some parameters do not record the highest
8219
** value.  For those parameters
8220
** nothing is written into *pHighwater and the resetFlag is ignored.)^
8221
** ^(Other parameters record only the highwater mark and not the current
8222
** value.  For these latter parameters nothing is written into *pCurrent.)^
8223
**
8224
** ^The sqlite3_status() and sqlite3_status64() routines return
8225
** SQLITE_OK on success and a non-zero [error code] on failure.
8226
**
8227
** If either the current value or the highwater mark is too large to
8228
** be represented by a 32-bit integer, then the values returned by
8229
** sqlite3_status() are undefined.
8230
**
8231
** See also: [sqlite3_db_status()]
8232
*/
8233
SQLITE_API int sqlite3_status(int op, int *pCurrent, int *pHighwater, int resetFlag);
8234
SQLITE_API int sqlite3_status64(
8235
  int op,
8236
  sqlite3_int64 *pCurrent,
8237
  sqlite3_int64 *pHighwater,
8238
  int resetFlag
8239
);
8240
8241
8242
/*
8243
** CAPI3REF: Status Parameters
8244
** KEYWORDS: {status parameters}
8245
**
8246
** These integer constants designate various run-time status parameters
8247
** that can be returned by [sqlite3_status()].
8248
**
8249
** <dl>
8250
** [[SQLITE_STATUS_MEMORY_USED]] ^(<dt>SQLITE_STATUS_MEMORY_USED</dt>
8251
** <dd>This parameter is the current amount of memory checked out
8252
** using [sqlite3_malloc()], either directly or indirectly.  The
8253
** figure includes calls made to [sqlite3_malloc()] by the application
8254
** and internal memory usage by the SQLite library.  Auxiliary page-cache
8255
** memory controlled by [SQLITE_CONFIG_PAGECACHE] is not included in
8256
** this parameter.  The amount returned is the sum of the allocation
8257
** sizes as reported by the xSize method in [sqlite3_mem_methods].</dd>)^
8258
**
8259
** [[SQLITE_STATUS_MALLOC_SIZE]] ^(<dt>SQLITE_STATUS_MALLOC_SIZE</dt>
8260
** <dd>This parameter records the largest memory allocation request
8261
** handed to [sqlite3_malloc()] or [sqlite3_realloc()] (or their
8262
** internal equivalents).  Only the value returned in the
8263
** *pHighwater parameter to [sqlite3_status()] is of interest.
8264
** The value written into the *pCurrent parameter is undefined.</dd>)^
8265
**
8266
** [[SQLITE_STATUS_MALLOC_COUNT]] ^(<dt>SQLITE_STATUS_MALLOC_COUNT</dt>
8267
** <dd>This parameter records the number of separate memory allocations
8268
** currently checked out.</dd>)^
8269
**
8270
** [[SQLITE_STATUS_PAGECACHE_USED]] ^(<dt>SQLITE_STATUS_PAGECACHE_USED</dt>
8271
** <dd>This parameter returns the number of pages used out of the
8272
** [pagecache memory allocator] that was configured using
8273
** [SQLITE_CONFIG_PAGECACHE].  The
8274
** value returned is in pages, not in bytes.</dd>)^
8275
**
8276
** [[SQLITE_STATUS_PAGECACHE_OVERFLOW]]
8277
** ^(<dt>SQLITE_STATUS_PAGECACHE_OVERFLOW</dt>
8278
** <dd>This parameter returns the number of bytes of page cache
8279
** allocation which could not be satisfied by the [SQLITE_CONFIG_PAGECACHE]
8280
** buffer and where forced to overflow to [sqlite3_malloc()].  The
8281
** returned value includes allocations that overflowed because they
8282
** where too large (they were larger than the "sz" parameter to
8283
** [SQLITE_CONFIG_PAGECACHE]) and allocations that overflowed because
8284
** no space was left in the page cache.</dd>)^
8285
**
8286
** [[SQLITE_STATUS_PAGECACHE_SIZE]] ^(<dt>SQLITE_STATUS_PAGECACHE_SIZE</dt>
8287
** <dd>This parameter records the largest memory allocation request
8288
** handed to the [pagecache memory allocator].  Only the value returned in the
8289
** *pHighwater parameter to [sqlite3_status()] is of interest.
8290
** The value written into the *pCurrent parameter is undefined.</dd>)^
8291
**
8292
** [[SQLITE_STATUS_SCRATCH_USED]] <dt>SQLITE_STATUS_SCRATCH_USED</dt>
8293
** <dd>No longer used.</dd>
8294
**
8295
** [[SQLITE_STATUS_SCRATCH_OVERFLOW]] ^(<dt>SQLITE_STATUS_SCRATCH_OVERFLOW</dt>
8296
** <dd>No longer used.</dd>
8297
**
8298
** [[SQLITE_STATUS_SCRATCH_SIZE]] <dt>SQLITE_STATUS_SCRATCH_SIZE</dt>
8299
** <dd>No longer used.</dd>
8300
**
8301
** [[SQLITE_STATUS_PARSER_STACK]] ^(<dt>SQLITE_STATUS_PARSER_STACK</dt>
8302
** <dd>The *pHighwater parameter records the deepest parser stack.
8303
** The *pCurrent value is undefined.  The *pHighwater value is only
8304
** meaningful if SQLite is compiled with [YYTRACKMAXSTACKDEPTH].</dd>)^
8305
** </dl>
8306
**
8307
** New status parameters may be added from time to time.
8308
*/
8309
#define SQLITE_STATUS_MEMORY_USED          0
8310
#define SQLITE_STATUS_PAGECACHE_USED       1
8311
#define SQLITE_STATUS_PAGECACHE_OVERFLOW   2
8312
#define SQLITE_STATUS_SCRATCH_USED         3  /* NOT USED */
8313
#define SQLITE_STATUS_SCRATCH_OVERFLOW     4  /* NOT USED */
8314
#define SQLITE_STATUS_MALLOC_SIZE          5
8315
#define SQLITE_STATUS_PARSER_STACK         6
8316
#define SQLITE_STATUS_PAGECACHE_SIZE       7
8317
#define SQLITE_STATUS_SCRATCH_SIZE         8  /* NOT USED */
8318
#define SQLITE_STATUS_MALLOC_COUNT         9
8319
8320
/*
8321
** CAPI3REF: Database Connection Status
8322
** METHOD: sqlite3
8323
**
8324
** ^This interface is used to retrieve runtime status information
8325
** about a single [database connection].  ^The first argument is the
8326
** database connection object to be interrogated.  ^The second argument
8327
** is an integer constant, taken from the set of
8328
** [SQLITE_DBSTATUS options], that
8329
** determines the parameter to interrogate.  The set of
8330
** [SQLITE_DBSTATUS options] is likely
8331
** to grow in future releases of SQLite.
8332
**
8333
** ^The current value of the requested parameter is written into *pCur
8334
** and the highest instantaneous value is written into *pHiwtr.  ^If
8335
** the resetFlg is true, then the highest instantaneous value is
8336
** reset back down to the current value.
8337
**
8338
** ^The sqlite3_db_status() routine returns SQLITE_OK on success and a
8339
** non-zero [error code] on failure.
8340
**
8341
** See also: [sqlite3_status()] and [sqlite3_stmt_status()].
8342
*/
8343
SQLITE_API int sqlite3_db_status(sqlite3*, int op, int *pCur, int *pHiwtr, int resetFlg);
8344
8345
/*
8346
** CAPI3REF: Status Parameters for database connections
8347
** KEYWORDS: {SQLITE_DBSTATUS options}
8348
**
8349
** These constants are the available integer "verbs" that can be passed as
8350
** the second argument to the [sqlite3_db_status()] interface.
8351
**
8352
** New verbs may be added in future releases of SQLite. Existing verbs
8353
** might be discontinued. Applications should check the return code from
8354
** [sqlite3_db_status()] to make sure that the call worked.
8355
** The [sqlite3_db_status()] interface will return a non-zero error code
8356
** if a discontinued or unsupported verb is invoked.
8357
**
8358
** <dl>
8359
** [[SQLITE_DBSTATUS_LOOKASIDE_USED]] ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_USED</dt>
8360
** <dd>This parameter returns the number of lookaside memory slots currently
8361
** checked out.</dd>)^
8362
**
8363
** [[SQLITE_DBSTATUS_LOOKASIDE_HIT]] ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_HIT</dt>
8364
** <dd>This parameter returns the number of malloc attempts that were
8365
** satisfied using lookaside memory. Only the high-water value is meaningful;
8366
** the current value is always zero.)^
8367
**
8368
** [[SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE]]
8369
** ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE</dt>
8370
** <dd>This parameter returns the number malloc attempts that might have
8371
** been satisfied using lookaside memory but failed due to the amount of
8372
** memory requested being larger than the lookaside slot size.
8373
** Only the high-water value is meaningful;
8374
** the current value is always zero.)^
8375
**
8376
** [[SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL]]
8377
** ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL</dt>
8378
** <dd>This parameter returns the number malloc attempts that might have
8379
** been satisfied using lookaside memory but failed due to all lookaside
8380
** memory already being in use.
8381
** Only the high-water value is meaningful;
8382
** the current value is always zero.)^
8383
**
8384
** [[SQLITE_DBSTATUS_CACHE_USED]] ^(<dt>SQLITE_DBSTATUS_CACHE_USED</dt>
8385
** <dd>This parameter returns the approximate number of bytes of heap
8386
** memory used by all pager caches associated with the database connection.)^
8387
** ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_USED is always 0.
8388
**
8389
** [[SQLITE_DBSTATUS_CACHE_USED_SHARED]]
8390
** ^(<dt>SQLITE_DBSTATUS_CACHE_USED_SHARED</dt>
8391
** <dd>This parameter is similar to DBSTATUS_CACHE_USED, except that if a
8392
** pager cache is shared between two or more connections the bytes of heap
8393
** memory used by that pager cache is divided evenly between the attached
8394
** connections.)^  In other words, if none of the pager caches associated
8395
** with the database connection are shared, this request returns the same
8396
** value as DBSTATUS_CACHE_USED. Or, if one or more or the pager caches are
8397
** shared, the value returned by this call will be smaller than that returned
8398
** by DBSTATUS_CACHE_USED. ^The highwater mark associated with
8399
** SQLITE_DBSTATUS_CACHE_USED_SHARED is always 0.
8400
**
8401
** [[SQLITE_DBSTATUS_SCHEMA_USED]] ^(<dt>SQLITE_DBSTATUS_SCHEMA_USED</dt>
8402
** <dd>This parameter returns the approximate number of bytes of heap
8403
** memory used to store the schema for all databases associated
8404
** with the connection - main, temp, and any [ATTACH]-ed databases.)^
8405
** ^The full amount of memory used by the schemas is reported, even if the
8406
** schema memory is shared with other database connections due to
8407
** [shared cache mode] being enabled.
8408
** ^The highwater mark associated with SQLITE_DBSTATUS_SCHEMA_USED is always 0.
8409
**
8410
** [[SQLITE_DBSTATUS_STMT_USED]] ^(<dt>SQLITE_DBSTATUS_STMT_USED</dt>
8411
** <dd>This parameter returns the approximate number of bytes of heap
8412
** and lookaside memory used by all prepared statements associated with
8413
** the database connection.)^
8414
** ^The highwater mark associated with SQLITE_DBSTATUS_STMT_USED is always 0.
8415
** </dd>
8416
**
8417
** [[SQLITE_DBSTATUS_CACHE_HIT]] ^(<dt>SQLITE_DBSTATUS_CACHE_HIT</dt>
8418
** <dd>This parameter returns the number of pager cache hits that have
8419
** occurred.)^ ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_HIT
8420
** is always 0.
8421
** </dd>
8422
**
8423
** [[SQLITE_DBSTATUS_CACHE_MISS]] ^(<dt>SQLITE_DBSTATUS_CACHE_MISS</dt>
8424
** <dd>This parameter returns the number of pager cache misses that have
8425
** occurred.)^ ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_MISS
8426
** is always 0.
8427
** </dd>
8428
**
8429
** [[SQLITE_DBSTATUS_CACHE_WRITE]] ^(<dt>SQLITE_DBSTATUS_CACHE_WRITE</dt>
8430
** <dd>This parameter returns the number of dirty cache entries that have
8431
** been written to disk. Specifically, the number of pages written to the
8432
** wal file in wal mode databases, or the number of pages written to the
8433
** database file in rollback mode databases. Any pages written as part of
8434
** transaction rollback or database recovery operations are not included.
8435
** If an IO or other error occurs while writing a page to disk, the effect
8436
** on subsequent SQLITE_DBSTATUS_CACHE_WRITE requests is undefined.)^ ^The
8437
** highwater mark associated with SQLITE_DBSTATUS_CACHE_WRITE is always 0.
8438
** </dd>
8439
**
8440
** [[SQLITE_DBSTATUS_CACHE_SPILL]] ^(<dt>SQLITE_DBSTATUS_CACHE_SPILL</dt>
8441
** <dd>This parameter returns the number of dirty cache entries that have
8442
** been written to disk in the middle of a transaction due to the page
8443
** cache overflowing. Transactions are more efficient if they are written
8444
** to disk all at once. When pages spill mid-transaction, that introduces
8445
** additional overhead. This parameter can be used help identify
8446
** inefficiencies that can be resolved by increasing the cache size.
8447
** </dd>
8448
**
8449
** [[SQLITE_DBSTATUS_DEFERRED_FKS]] ^(<dt>SQLITE_DBSTATUS_DEFERRED_FKS</dt>
8450
** <dd>This parameter returns zero for the current value if and only if
8451
** all foreign key constraints (deferred or immediate) have been
8452
** resolved.)^  ^The highwater mark is always 0.
8453
** </dd>
8454
** </dl>
8455
*/
8456
#define SQLITE_DBSTATUS_LOOKASIDE_USED       0
8457
#define SQLITE_DBSTATUS_CACHE_USED           1
8458
#define SQLITE_DBSTATUS_SCHEMA_USED          2
8459
#define SQLITE_DBSTATUS_STMT_USED            3
8460
#define SQLITE_DBSTATUS_LOOKASIDE_HIT        4
8461
#define SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE  5
8462
#define SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL  6
8463
#define SQLITE_DBSTATUS_CACHE_HIT            7
8464
#define SQLITE_DBSTATUS_CACHE_MISS           8
8465
#define SQLITE_DBSTATUS_CACHE_WRITE          9
8466
#define SQLITE_DBSTATUS_DEFERRED_FKS        10
8467
#define SQLITE_DBSTATUS_CACHE_USED_SHARED   11
8468
#define SQLITE_DBSTATUS_CACHE_SPILL         12
8469
#define SQLITE_DBSTATUS_MAX                 12   /* Largest defined DBSTATUS */
8470
8471
8472
/*
8473
** CAPI3REF: Prepared Statement Status
8474
** METHOD: sqlite3_stmt
8475
**
8476
** ^(Each prepared statement maintains various
8477
** [SQLITE_STMTSTATUS counters] that measure the number
8478
** of times it has performed specific operations.)^  These counters can
8479
** be used to monitor the performance characteristics of the prepared
8480
** statements.  For example, if the number of table steps greatly exceeds
8481
** the number of table searches or result rows, that would tend to indicate
8482
** that the prepared statement is using a full table scan rather than
8483
** an index.
8484
**
8485
** ^(This interface is used to retrieve and reset counter values from
8486
** a [prepared statement].  The first argument is the prepared statement
8487
** object to be interrogated.  The second argument
8488
** is an integer code for a specific [SQLITE_STMTSTATUS counter]
8489
** to be interrogated.)^
8490
** ^The current value of the requested counter is returned.
8491
** ^If the resetFlg is true, then the counter is reset to zero after this
8492
** interface call returns.
8493
**
8494
** See also: [sqlite3_status()] and [sqlite3_db_status()].
8495
*/
8496
SQLITE_API int sqlite3_stmt_status(sqlite3_stmt*, int op,int resetFlg);
8497
8498
/*
8499
** CAPI3REF: Status Parameters for prepared statements
8500
** KEYWORDS: {SQLITE_STMTSTATUS counter} {SQLITE_STMTSTATUS counters}
8501
**
8502
** These preprocessor macros define integer codes that name counter
8503
** values associated with the [sqlite3_stmt_status()] interface.
8504
** The meanings of the various counters are as follows:
8505
**
8506
** <dl>
8507
** [[SQLITE_STMTSTATUS_FULLSCAN_STEP]] <dt>SQLITE_STMTSTATUS_FULLSCAN_STEP</dt>
8508
** <dd>^This is the number of times that SQLite has stepped forward in
8509
** a table as part of a full table scan.  Large numbers for this counter
8510
** may indicate opportunities for performance improvement through
8511
** careful use of indices.</dd>
8512
**
8513
** [[SQLITE_STMTSTATUS_SORT]] <dt>SQLITE_STMTSTATUS_SORT</dt>
8514
** <dd>^This is the number of sort operations that have occurred.
8515
** A non-zero value in this counter may indicate an opportunity to
8516
** improvement performance through careful use of indices.</dd>
8517
**
8518
** [[SQLITE_STMTSTATUS_AUTOINDEX]] <dt>SQLITE_STMTSTATUS_AUTOINDEX</dt>
8519
** <dd>^This is the number of rows inserted into transient indices that
8520
** were created automatically in order to help joins run faster.
8521
** A non-zero value in this counter may indicate an opportunity to
8522
** improvement performance by adding permanent indices that do not
8523
** need to be reinitialized each time the statement is run.</dd>
8524
**
8525
** [[SQLITE_STMTSTATUS_VM_STEP]] <dt>SQLITE_STMTSTATUS_VM_STEP</dt>
8526
** <dd>^This is the number of virtual machine operations executed
8527
** by the prepared statement if that number is less than or equal
8528
** to 2147483647.  The number of virtual machine operations can be
8529
** used as a proxy for the total work done by the prepared statement.
8530
** If the number of virtual machine operations exceeds 2147483647
8531
** then the value returned by this statement status code is undefined.
8532
**
8533
** [[SQLITE_STMTSTATUS_REPREPARE]] <dt>SQLITE_STMTSTATUS_REPREPARE</dt>
8534
** <dd>^This is the number of times that the prepare statement has been
8535
** automatically regenerated due to schema changes or changes to
8536
** [bound parameters] that might affect the query plan.
8537
**
8538
** [[SQLITE_STMTSTATUS_RUN]] <dt>SQLITE_STMTSTATUS_RUN</dt>
8539
** <dd>^This is the number of times that the prepared statement has
8540
** been run.  A single "run" for the purposes of this counter is one
8541
** or more calls to [sqlite3_step()] followed by a call to [sqlite3_reset()].
8542
** The counter is incremented on the first [sqlite3_step()] call of each
8543
** cycle.
8544
**
8545
** [[SQLITE_STMTSTATUS_FILTER_MISS]]
8546
** [[SQLITE_STMTSTATUS_FILTER HIT]]
8547
** <dt>SQLITE_STMTSTATUS_FILTER_HIT<br>
8548
** SQLITE_STMTSTATUS_FILTER_MISS</dt>
8549
** <dd>^SQLITE_STMTSTATUS_FILTER_HIT is the number of times that a join
8550
** step was bypassed because a Bloom filter returned not-found.  The
8551
** corresponding SQLITE_STMTSTATUS_FILTER_MISS value is the number of
8552
** times that the Bloom filter returned a find, and thus the join step
8553
** had to be processed as normal.
8554
**
8555
** [[SQLITE_STMTSTATUS_MEMUSED]] <dt>SQLITE_STMTSTATUS_MEMUSED</dt>
8556
** <dd>^This is the approximate number of bytes of heap memory
8557
** used to store the prepared statement.  ^This value is not actually
8558
** a counter, and so the resetFlg parameter to sqlite3_stmt_status()
8559
** is ignored when the opcode is SQLITE_STMTSTATUS_MEMUSED.
8560
** </dd>
8561
** </dl>
8562
*/
8563
#define SQLITE_STMTSTATUS_FULLSCAN_STEP     1
8564
#define SQLITE_STMTSTATUS_SORT              2
8565
#define SQLITE_STMTSTATUS_AUTOINDEX         3
8566
#define SQLITE_STMTSTATUS_VM_STEP           4
8567
#define SQLITE_STMTSTATUS_REPREPARE         5
8568
#define SQLITE_STMTSTATUS_RUN               6
8569
#define SQLITE_STMTSTATUS_FILTER_MISS       7
8570
#define SQLITE_STMTSTATUS_FILTER_HIT        8
8571
#define SQLITE_STMTSTATUS_MEMUSED           99
8572
8573
/*
8574
** CAPI3REF: Custom Page Cache Object
8575
**
8576
** The sqlite3_pcache type is opaque.  It is implemented by
8577
** the pluggable module.  The SQLite core has no knowledge of
8578
** its size or internal structure and never deals with the
8579
** sqlite3_pcache object except by holding and passing pointers
8580
** to the object.
8581
**
8582
** See [sqlite3_pcache_methods2] for additional information.
8583
*/
8584
typedef struct sqlite3_pcache sqlite3_pcache;
8585
8586
/*
8587
** CAPI3REF: Custom Page Cache Object
8588
**
8589
** The sqlite3_pcache_page object represents a single page in the
8590
** page cache.  The page cache will allocate instances of this
8591
** object.  Various methods of the page cache use pointers to instances
8592
** of this object as parameters or as their return value.
8593
**
8594
** See [sqlite3_pcache_methods2] for additional information.
8595
*/
8596
typedef struct sqlite3_pcache_page sqlite3_pcache_page;
8597
struct sqlite3_pcache_page {
8598
  void *pBuf;        /* The content of the page */
8599
  void *pExtra;      /* Extra information associated with the page */
8600
};
8601
8602
/*
8603
** CAPI3REF: Application Defined Page Cache.
8604
** KEYWORDS: {page cache}
8605
**
8606
** ^(The [sqlite3_config]([SQLITE_CONFIG_PCACHE2], ...) interface can
8607
** register an alternative page cache implementation by passing in an
8608
** instance of the sqlite3_pcache_methods2 structure.)^
8609
** In many applications, most of the heap memory allocated by
8610
** SQLite is used for the page cache.
8611
** By implementing a
8612
** custom page cache using this API, an application can better control
8613
** the amount of memory consumed by SQLite, the way in which
8614
** that memory is allocated and released, and the policies used to
8615
** determine exactly which parts of a database file are cached and for
8616
** how long.
8617
**
8618
** The alternative page cache mechanism is an
8619
** extreme measure that is only needed by the most demanding applications.
8620
** The built-in page cache is recommended for most uses.
8621
**
8622
** ^(The contents of the sqlite3_pcache_methods2 structure are copied to an
8623
** internal buffer by SQLite within the call to [sqlite3_config].  Hence
8624
** the application may discard the parameter after the call to
8625
** [sqlite3_config()] returns.)^
8626
**
8627
** [[the xInit() page cache method]]
8628
** ^(The xInit() method is called once for each effective
8629
** call to [sqlite3_initialize()])^
8630
** (usually only once during the lifetime of the process). ^(The xInit()
8631
** method is passed a copy of the sqlite3_pcache_methods2.pArg value.)^
8632
** The intent of the xInit() method is to set up global data structures
8633
** required by the custom page cache implementation.
8634
** ^(If the xInit() method is NULL, then the
8635
** built-in default page cache is used instead of the application defined
8636
** page cache.)^
8637
**
8638
** [[the xShutdown() page cache method]]
8639
** ^The xShutdown() method is called by [sqlite3_shutdown()].
8640
** It can be used to clean up
8641
** any outstanding resources before process shutdown, if required.
8642
** ^The xShutdown() method may be NULL.
8643
**
8644
** ^SQLite automatically serializes calls to the xInit method,
8645
** so the xInit method need not be threadsafe.  ^The
8646
** xShutdown method is only called from [sqlite3_shutdown()] so it does
8647
** not need to be threadsafe either.  All other methods must be threadsafe
8648
** in multithreaded applications.
8649
**
8650
** ^SQLite will never invoke xInit() more than once without an intervening
8651
** call to xShutdown().
8652
**
8653
** [[the xCreate() page cache methods]]
8654
** ^SQLite invokes the xCreate() method to construct a new cache instance.
8655
** SQLite will typically create one cache instance for each open database file,
8656
** though this is not guaranteed. ^The
8657
** first parameter, szPage, is the size in bytes of the pages that must
8658
** be allocated by the cache.  ^szPage will always a power of two.  ^The
8659
** second parameter szExtra is a number of bytes of extra storage
8660
** associated with each page cache entry.  ^The szExtra parameter will
8661
** a number less than 250.  SQLite will use the
8662
** extra szExtra bytes on each page to store metadata about the underlying
8663
** database page on disk.  The value passed into szExtra depends
8664
** on the SQLite version, the target platform, and how SQLite was compiled.
8665
** ^The third argument to xCreate(), bPurgeable, is true if the cache being
8666
** created will be used to cache database pages of a file stored on disk, or
8667
** false if it is used for an in-memory database. The cache implementation
8668
** does not have to do anything special based with the value of bPurgeable;
8669
** it is purely advisory.  ^On a cache where bPurgeable is false, SQLite will
8670
** never invoke xUnpin() except to deliberately delete a page.
8671
** ^In other words, calls to xUnpin() on a cache with bPurgeable set to
8672
** false will always have the "discard" flag set to true.
8673
** ^Hence, a cache created with bPurgeable false will
8674
** never contain any unpinned pages.
8675
**
8676
** [[the xCachesize() page cache method]]
8677
** ^(The xCachesize() method may be called at any time by SQLite to set the
8678
** suggested maximum cache-size (number of pages stored by) the cache
8679
** instance passed as the first argument. This is the value configured using
8680
** the SQLite "[PRAGMA cache_size]" command.)^  As with the bPurgeable
8681
** parameter, the implementation is not required to do anything with this
8682
** value; it is advisory only.
8683
**
8684
** [[the xPagecount() page cache methods]]
8685
** The xPagecount() method must return the number of pages currently
8686
** stored in the cache, both pinned and unpinned.
8687
**
8688
** [[the xFetch() page cache methods]]
8689
** The xFetch() method locates a page in the cache and returns a pointer to
8690
** an sqlite3_pcache_page object associated with that page, or a NULL pointer.
8691
** The pBuf element of the returned sqlite3_pcache_page object will be a
8692
** pointer to a buffer of szPage bytes used to store the content of a
8693
** single database page.  The pExtra element of sqlite3_pcache_page will be
8694
** a pointer to the szExtra bytes of extra storage that SQLite has requested
8695
** for each entry in the page cache.
8696
**
8697
** The page to be fetched is determined by the key. ^The minimum key value
8698
** is 1.  After it has been retrieved using xFetch, the page is considered
8699
** to be "pinned".
8700
**
8701
** If the requested page is already in the page cache, then the page cache
8702
** implementation must return a pointer to the page buffer with its content
8703
** intact.  If the requested page is not already in the cache, then the
8704
** cache implementation should use the value of the createFlag
8705
** parameter to help it determined what action to take:
8706
**
8707
** <table border=1 width=85% align=center>
8708
** <tr><th> createFlag <th> Behavior when page is not already in cache
8709
** <tr><td> 0 <td> Do not allocate a new page.  Return NULL.
8710
** <tr><td> 1 <td> Allocate a new page if it easy and convenient to do so.
8711
**                 Otherwise return NULL.
8712
** <tr><td> 2 <td> Make every effort to allocate a new page.  Only return
8713
**                 NULL if allocating a new page is effectively impossible.
8714
** </table>
8715
**
8716
** ^(SQLite will normally invoke xFetch() with a createFlag of 0 or 1.  SQLite
8717
** will only use a createFlag of 2 after a prior call with a createFlag of 1
8718
** failed.)^  In between the xFetch() calls, SQLite may
8719
** attempt to unpin one or more cache pages by spilling the content of
8720
** pinned pages to disk and synching the operating system disk cache.
8721
**
8722
** [[the xUnpin() page cache method]]
8723
** ^xUnpin() is called by SQLite with a pointer to a currently pinned page
8724
** as its second argument.  If the third parameter, discard, is non-zero,
8725
** then the page must be evicted from the cache.
8726
** ^If the discard parameter is
8727
** zero, then the page may be discarded or retained at the discretion of
8728
** page cache implementation. ^The page cache implementation
8729
** may choose to evict unpinned pages at any time.
8730
**
8731
** The cache must not perform any reference counting. A single
8732
** call to xUnpin() unpins the page regardless of the number of prior calls
8733
** to xFetch().
8734
**
8735
** [[the xRekey() page cache methods]]
8736
** The xRekey() method is used to change the key value associated with the
8737
** page passed as the second argument. If the cache
8738
** previously contains an entry associated with newKey, it must be
8739
** discarded. ^Any prior cache entry associated with newKey is guaranteed not
8740
** to be pinned.
8741
**
8742
** When SQLite calls the xTruncate() method, the cache must discard all
8743
** existing cache entries with page numbers (keys) greater than or equal
8744
** to the value of the iLimit parameter passed to xTruncate(). If any
8745
** of these pages are pinned, they are implicitly unpinned, meaning that
8746
** they can be safely discarded.
8747
**
8748
** [[the xDestroy() page cache method]]
8749
** ^The xDestroy() method is used to delete a cache allocated by xCreate().
8750
** All resources associated with the specified cache should be freed. ^After
8751
** calling the xDestroy() method, SQLite considers the [sqlite3_pcache*]
8752
** handle invalid, and will not use it with any other sqlite3_pcache_methods2
8753
** functions.
8754
**
8755
** [[the xShrink() page cache method]]
8756
** ^SQLite invokes the xShrink() method when it wants the page cache to
8757
** free up as much of heap memory as possible.  The page cache implementation
8758
** is not obligated to free any memory, but well-behaved implementations should
8759
** do their best.
8760
*/
8761
typedef struct sqlite3_pcache_methods2 sqlite3_pcache_methods2;
8762
struct sqlite3_pcache_methods2 {
8763
  int iVersion;
8764
  void *pArg;
8765
  int (*xInit)(void*);
8766
  void (*xShutdown)(void*);
8767
  sqlite3_pcache *(*xCreate)(int szPage, int szExtra, int bPurgeable);
8768
  void (*xCachesize)(sqlite3_pcache*, int nCachesize);
8769
  int (*xPagecount)(sqlite3_pcache*);
8770
  sqlite3_pcache_page *(*xFetch)(sqlite3_pcache*, unsigned key, int createFlag);
8771
  void (*xUnpin)(sqlite3_pcache*, sqlite3_pcache_page*, int discard);
8772
  void (*xRekey)(sqlite3_pcache*, sqlite3_pcache_page*,
8773
      unsigned oldKey, unsigned newKey);
8774
  void (*xTruncate)(sqlite3_pcache*, unsigned iLimit);
8775
  void (*xDestroy)(sqlite3_pcache*);
8776
  void (*xShrink)(sqlite3_pcache*);
8777
};
8778
8779
/*
8780
** This is the obsolete pcache_methods object that has now been replaced
8781
** by sqlite3_pcache_methods2.  This object is not used by SQLite.  It is
8782
** retained in the header file for backwards compatibility only.
8783
*/
8784
typedef struct sqlite3_pcache_methods sqlite3_pcache_methods;
8785
struct sqlite3_pcache_methods {
8786
  void *pArg;
8787
  int (*xInit)(void*);
8788
  void (*xShutdown)(void*);
8789
  sqlite3_pcache *(*xCreate)(int szPage, int bPurgeable);
8790
  void (*xCachesize)(sqlite3_pcache*, int nCachesize);
8791
  int (*xPagecount)(sqlite3_pcache*);
8792
  void *(*xFetch)(sqlite3_pcache*, unsigned key, int createFlag);
8793
  void (*xUnpin)(sqlite3_pcache*, void*, int discard);
8794
  void (*xRekey)(sqlite3_pcache*, void*, unsigned oldKey, unsigned newKey);
8795
  void (*xTruncate)(sqlite3_pcache*, unsigned iLimit);
8796
  void (*xDestroy)(sqlite3_pcache*);
8797
};
8798
8799
8800
/*
8801
** CAPI3REF: Online Backup Object
8802
**
8803
** The sqlite3_backup object records state information about an ongoing
8804
** online backup operation.  ^The sqlite3_backup object is created by
8805
** a call to [sqlite3_backup_init()] and is destroyed by a call to
8806
** [sqlite3_backup_finish()].
8807
**
8808
** See Also: [Using the SQLite Online Backup API]
8809
*/
8810
typedef struct sqlite3_backup sqlite3_backup;
8811
8812
/*
8813
** CAPI3REF: Online Backup API.
8814
**
8815
** The backup API copies the content of one database into another.
8816
** It is useful either for creating backups of databases or
8817
** for copying in-memory databases to or from persistent files.
8818
**
8819
** See Also: [Using the SQLite Online Backup API]
8820
**
8821
** ^SQLite holds a write transaction open on the destination database file
8822
** for the duration of the backup operation.
8823
** ^The source database is read-locked only while it is being read;
8824
** it is not locked continuously for the entire backup operation.
8825
** ^Thus, the backup may be performed on a live source database without
8826
** preventing other database connections from
8827
** reading or writing to the source database while the backup is underway.
8828
**
8829
** ^(To perform a backup operation:
8830
**   <ol>
8831
**     <li><b>sqlite3_backup_init()</b> is called once to initialize the
8832
**         backup,
8833
**     <li><b>sqlite3_backup_step()</b> is called one or more times to transfer
8834
**         the data between the two databases, and finally
8835
**     <li><b>sqlite3_backup_finish()</b> is called to release all resources
8836
**         associated with the backup operation.
8837
**   </ol>)^
8838
** There should be exactly one call to sqlite3_backup_finish() for each
8839
** successful call to sqlite3_backup_init().
8840
**
8841
** [[sqlite3_backup_init()]] <b>sqlite3_backup_init()</b>
8842
**
8843
** ^The D and N arguments to sqlite3_backup_init(D,N,S,M) are the
8844
** [database connection] associated with the destination database
8845
** and the database name, respectively.
8846
** ^The database name is "main" for the main database, "temp" for the
8847
** temporary database, or the name specified after the AS keyword in
8848
** an [ATTACH] statement for an attached database.
8849
** ^The S and M arguments passed to
8850
** sqlite3_backup_init(D,N,S,M) identify the [database connection]
8851
** and database name of the source database, respectively.
8852
** ^The source and destination [database connections] (parameters S and D)
8853
** must be different or else sqlite3_backup_init(D,N,S,M) will fail with
8854
** an error.
8855
**
8856
** ^A call to sqlite3_backup_init() will fail, returning NULL, if
8857
** there is already a read or read-write transaction open on the
8858
** destination database.
8859
**
8860
** ^If an error occurs within sqlite3_backup_init(D,N,S,M), then NULL is
8861
** returned and an error code and error message are stored in the
8862
** destination [database connection] D.
8863
** ^The error code and message for the failed call to sqlite3_backup_init()
8864
** can be retrieved using the [sqlite3_errcode()], [sqlite3_errmsg()], and/or
8865
** [sqlite3_errmsg16()] functions.
8866
** ^A successful call to sqlite3_backup_init() returns a pointer to an
8867
** [sqlite3_backup] object.
8868
** ^The [sqlite3_backup] object may be used with the sqlite3_backup_step() and
8869
** sqlite3_backup_finish() functions to perform the specified backup
8870
** operation.
8871
**
8872
** [[sqlite3_backup_step()]] <b>sqlite3_backup_step()</b>
8873
**
8874
** ^Function sqlite3_backup_step(B,N) will copy up to N pages between
8875
** the source and destination databases specified by [sqlite3_backup] object B.
8876
** ^If N is negative, all remaining source pages are copied.
8877
** ^If sqlite3_backup_step(B,N) successfully copies N pages and there
8878
** are still more pages to be copied, then the function returns [SQLITE_OK].
8879
** ^If sqlite3_backup_step(B,N) successfully finishes copying all pages
8880
** from source to destination, then it returns [SQLITE_DONE].
8881
** ^If an error occurs while running sqlite3_backup_step(B,N),
8882
** then an [error code] is returned. ^As well as [SQLITE_OK] and
8883
** [SQLITE_DONE], a call to sqlite3_backup_step() may return [SQLITE_READONLY],
8884
** [SQLITE_NOMEM], [SQLITE_BUSY], [SQLITE_LOCKED], or an
8885
** [SQLITE_IOERR_ACCESS | SQLITE_IOERR_XXX] extended error code.
8886
**
8887
** ^(The sqlite3_backup_step() might return [SQLITE_READONLY] if
8888
** <ol>
8889
** <li> the destination database was opened read-only, or
8890
** <li> the destination database is using write-ahead-log journaling
8891
** and the destination and source page sizes differ, or
8892
** <li> the destination database is an in-memory database and the
8893
** destination and source page sizes differ.
8894
** </ol>)^
8895
**
8896
** ^If sqlite3_backup_step() cannot obtain a required file-system lock, then
8897
** the [sqlite3_busy_handler | busy-handler function]
8898
** is invoked (if one is specified). ^If the
8899
** busy-handler returns non-zero before the lock is available, then
8900
** [SQLITE_BUSY] is returned to the caller. ^In this case the call to
8901
** sqlite3_backup_step() can be retried later. ^If the source
8902
** [database connection]
8903
** is being used to write to the source database when sqlite3_backup_step()
8904
** is called, then [SQLITE_LOCKED] is returned immediately. ^Again, in this
8905
** case the call to sqlite3_backup_step() can be retried later on. ^(If
8906
** [SQLITE_IOERR_ACCESS | SQLITE_IOERR_XXX], [SQLITE_NOMEM], or
8907
** [SQLITE_READONLY] is returned, then
8908
** there is no point in retrying the call to sqlite3_backup_step(). These
8909
** errors are considered fatal.)^  The application must accept
8910
** that the backup operation has failed and pass the backup operation handle
8911
** to the sqlite3_backup_finish() to release associated resources.
8912
**
8913
** ^The first call to sqlite3_backup_step() obtains an exclusive lock
8914
** on the destination file. ^The exclusive lock is not released until either
8915
** sqlite3_backup_finish() is called or the backup operation is complete
8916
** and sqlite3_backup_step() returns [SQLITE_DONE].  ^Every call to
8917
** sqlite3_backup_step() obtains a [shared lock] on the source database that
8918
** lasts for the duration of the sqlite3_backup_step() call.
8919
** ^Because the source database is not locked between calls to
8920
** sqlite3_backup_step(), the source database may be modified mid-way
8921
** through the backup process.  ^If the source database is modified by an
8922
** external process or via a database connection other than the one being
8923
** used by the backup operation, then the backup will be automatically
8924
** restarted by the next call to sqlite3_backup_step(). ^If the source
8925
** database is modified by the using the same database connection as is used
8926
** by the backup operation, then the backup database is automatically
8927
** updated at the same time.
8928
**
8929
** [[sqlite3_backup_finish()]] <b>sqlite3_backup_finish()</b>
8930
**
8931
** When sqlite3_backup_step() has returned [SQLITE_DONE], or when the
8932
** application wishes to abandon the backup operation, the application
8933
** should destroy the [sqlite3_backup] by passing it to sqlite3_backup_finish().
8934
** ^The sqlite3_backup_finish() interfaces releases all
8935
** resources associated with the [sqlite3_backup] object.
8936
** ^If sqlite3_backup_step() has not yet returned [SQLITE_DONE], then any
8937
** active write-transaction on the destination database is rolled back.
8938
** The [sqlite3_backup] object is invalid
8939
** and may not be used following a call to sqlite3_backup_finish().
8940
**
8941
** ^The value returned by sqlite3_backup_finish is [SQLITE_OK] if no
8942
** sqlite3_backup_step() errors occurred, regardless or whether or not
8943
** sqlite3_backup_step() completed.
8944
** ^If an out-of-memory condition or IO error occurred during any prior
8945
** sqlite3_backup_step() call on the same [sqlite3_backup] object, then
8946
** sqlite3_backup_finish() returns the corresponding [error code].
8947
**
8948
** ^A return of [SQLITE_BUSY] or [SQLITE_LOCKED] from sqlite3_backup_step()
8949
** is not a permanent error and does not affect the return value of
8950
** sqlite3_backup_finish().
8951
**
8952
** [[sqlite3_backup_remaining()]] [[sqlite3_backup_pagecount()]]
8953
** <b>sqlite3_backup_remaining() and sqlite3_backup_pagecount()</b>
8954
**
8955
** ^The sqlite3_backup_remaining() routine returns the number of pages still
8956
** to be backed up at the conclusion of the most recent sqlite3_backup_step().
8957
** ^The sqlite3_backup_pagecount() routine returns the total number of pages
8958
** in the source database at the conclusion of the most recent
8959
** sqlite3_backup_step().
8960
** ^(The values returned by these functions are only updated by
8961
** sqlite3_backup_step(). If the source database is modified in a way that
8962
** changes the size of the source database or the number of pages remaining,
8963
** those changes are not reflected in the output of sqlite3_backup_pagecount()
8964
** and sqlite3_backup_remaining() until after the next
8965
** sqlite3_backup_step().)^
8966
**
8967
** <b>Concurrent Usage of Database Handles</b>
8968
**
8969
** ^The source [database connection] may be used by the application for other
8970
** purposes while a backup operation is underway or being initialized.
8971
** ^If SQLite is compiled and configured to support threadsafe database
8972
** connections, then the source database connection may be used concurrently
8973
** from within other threads.
8974
**
8975
** However, the application must guarantee that the destination
8976
** [database connection] is not passed to any other API (by any thread) after
8977
** sqlite3_backup_init() is called and before the corresponding call to
8978
** sqlite3_backup_finish().  SQLite does not currently check to see
8979
** if the application incorrectly accesses the destination [database connection]
8980
** and so no error code is reported, but the operations may malfunction
8981
** nevertheless.  Use of the destination database connection while a
8982
** backup is in progress might also also cause a mutex deadlock.
8983
**
8984
** If running in [shared cache mode], the application must
8985
** guarantee that the shared cache used by the destination database
8986
** is not accessed while the backup is running. In practice this means
8987
** that the application must guarantee that the disk file being
8988
** backed up to is not accessed by any connection within the process,
8989
** not just the specific connection that was passed to sqlite3_backup_init().
8990
**
8991
** The [sqlite3_backup] object itself is partially threadsafe. Multiple
8992
** threads may safely make multiple concurrent calls to sqlite3_backup_step().
8993
** However, the sqlite3_backup_remaining() and sqlite3_backup_pagecount()
8994
** APIs are not strictly speaking threadsafe. If they are invoked at the
8995
** same time as another thread is invoking sqlite3_backup_step() it is
8996
** possible that they return invalid values.
8997
*/
8998
SQLITE_API sqlite3_backup *sqlite3_backup_init(
8999
  sqlite3 *pDest,                        /* Destination database handle */
9000
  const char *zDestName,                 /* Destination database name */
9001
  sqlite3 *pSource,                      /* Source database handle */
9002
  const char *zSourceName                /* Source database name */
9003
);
9004
SQLITE_API int sqlite3_backup_step(sqlite3_backup *p, int nPage);
9005
SQLITE_API int sqlite3_backup_finish(sqlite3_backup *p);
9006
SQLITE_API int sqlite3_backup_remaining(sqlite3_backup *p);
9007
SQLITE_API int sqlite3_backup_pagecount(sqlite3_backup *p);
9008
9009
/*
9010
** CAPI3REF: Unlock Notification
9011
** METHOD: sqlite3
9012
**
9013
** ^When running in shared-cache mode, a database operation may fail with
9014
** an [SQLITE_LOCKED] error if the required locks on the shared-cache or
9015
** individual tables within the shared-cache cannot be obtained. See
9016
** [SQLite Shared-Cache Mode] for a description of shared-cache locking.
9017
** ^This API may be used to register a callback that SQLite will invoke
9018
** when the connection currently holding the required lock relinquishes it.
9019
** ^This API is only available if the library was compiled with the
9020
** [SQLITE_ENABLE_UNLOCK_NOTIFY] C-preprocessor symbol defined.
9021
**
9022
** See Also: [Using the SQLite Unlock Notification Feature].
9023
**
9024
** ^Shared-cache locks are released when a database connection concludes
9025
** its current transaction, either by committing it or rolling it back.
9026
**
9027
** ^When a connection (known as the blocked connection) fails to obtain a
9028
** shared-cache lock and SQLITE_LOCKED is returned to the caller, the
9029
** identity of the database connection (the blocking connection) that
9030
** has locked the required resource is stored internally. ^After an
9031
** application receives an SQLITE_LOCKED error, it may call the
9032
** sqlite3_unlock_notify() method with the blocked connection handle as
9033
** the first argument to register for a callback that will be invoked
9034
** when the blocking connections current transaction is concluded. ^The
9035
** callback is invoked from within the [sqlite3_step] or [sqlite3_close]
9036
** call that concludes the blocking connection's transaction.
9037
**
9038
** ^(If sqlite3_unlock_notify() is called in a multi-threaded application,
9039
** there is a chance that the blocking connection will have already
9040
** concluded its transaction by the time sqlite3_unlock_notify() is invoked.
9041
** If this happens, then the specified callback is invoked immediately,
9042
** from within the call to sqlite3_unlock_notify().)^
9043
**
9044
** ^If the blocked connection is attempting to obtain a write-lock on a
9045
** shared-cache table, and more than one other connection currently holds
9046
** a read-lock on the same table, then SQLite arbitrarily selects one of
9047
** the other connections to use as the blocking connection.
9048
**
9049
** ^(There may be at most one unlock-notify callback registered by a
9050
** blocked connection. If sqlite3_unlock_notify() is called when the
9051
** blocked connection already has a registered unlock-notify callback,
9052
** then the new callback replaces the old.)^ ^If sqlite3_unlock_notify() is
9053
** called with a NULL pointer as its second argument, then any existing
9054
** unlock-notify callback is canceled. ^The blocked connections
9055
** unlock-notify callback may also be canceled by closing the blocked
9056
** connection using [sqlite3_close()].
9057
**
9058
** The unlock-notify callback is not reentrant. If an application invokes
9059
** any sqlite3_xxx API functions from within an unlock-notify callback, a
9060
** crash or deadlock may be the result.
9061
**
9062
** ^Unless deadlock is detected (see below), sqlite3_unlock_notify() always
9063
** returns SQLITE_OK.
9064
**
9065
** <b>Callback Invocation Details</b>
9066
**
9067
** When an unlock-notify callback is registered, the application provides a
9068
** single void* pointer that is passed to the callback when it is invoked.
9069
** However, the signature of the callback function allows SQLite to pass
9070
** it an array of void* context pointers. The first argument passed to
9071
** an unlock-notify callback is a pointer to an array of void* pointers,
9072
** and the second is the number of entries in the array.
9073
**
9074
** When a blocking connection's transaction is concluded, there may be
9075
** more than one blocked connection that has registered for an unlock-notify
9076
** callback. ^If two or more such blocked connections have specified the
9077
** same callback function, then instead of invoking the callback function
9078
** multiple times, it is invoked once with the set of void* context pointers
9079
** specified by the blocked connections bundled together into an array.
9080
** This gives the application an opportunity to prioritize any actions
9081
** related to the set of unblocked database connections.
9082
**
9083
** <b>Deadlock Detection</b>
9084
**
9085
** Assuming that after registering for an unlock-notify callback a
9086
** database waits for the callback to be issued before taking any further
9087
** action (a reasonable assumption), then using this API may cause the
9088
** application to deadlock. For example, if connection X is waiting for
9089
** connection Y's transaction to be concluded, and similarly connection
9090
** Y is waiting on connection X's transaction, then neither connection
9091
** will proceed and the system may remain deadlocked indefinitely.
9092
**
9093
** To avoid this scenario, the sqlite3_unlock_notify() performs deadlock
9094
** detection. ^If a given call to sqlite3_unlock_notify() would put the
9095
** system in a deadlocked state, then SQLITE_LOCKED is returned and no
9096
** unlock-notify callback is registered. The system is said to be in
9097
** a deadlocked state if connection A has registered for an unlock-notify
9098
** callback on the conclusion of connection B's transaction, and connection
9099
** B has itself registered for an unlock-notify callback when connection
9100
** A's transaction is concluded. ^Indirect deadlock is also detected, so
9101
** the system is also considered to be deadlocked if connection B has
9102
** registered for an unlock-notify callback on the conclusion of connection
9103
** C's transaction, where connection C is waiting on connection A. ^Any
9104
** number of levels of indirection are allowed.
9105
**
9106
** <b>The "DROP TABLE" Exception</b>
9107
**
9108
** When a call to [sqlite3_step()] returns SQLITE_LOCKED, it is almost
9109
** always appropriate to call sqlite3_unlock_notify(). There is however,
9110
** one exception. When executing a "DROP TABLE" or "DROP INDEX" statement,
9111
** SQLite checks if there are any currently executing SELECT statements
9112
** that belong to the same connection. If there are, SQLITE_LOCKED is
9113
** returned. In this case there is no "blocking connection", so invoking
9114
** sqlite3_unlock_notify() results in the unlock-notify callback being
9115
** invoked immediately. If the application then re-attempts the "DROP TABLE"
9116
** or "DROP INDEX" query, an infinite loop might be the result.
9117
**
9118
** One way around this problem is to check the extended error code returned
9119
** by an sqlite3_step() call. ^(If there is a blocking connection, then the
9120
** extended error code is set to SQLITE_LOCKED_SHAREDCACHE. Otherwise, in
9121
** the special "DROP TABLE/INDEX" case, the extended error code is just
9122
** SQLITE_LOCKED.)^
9123
*/
9124
SQLITE_API int sqlite3_unlock_notify(
9125
  sqlite3 *pBlocked,                          /* Waiting connection */
9126
  void (*xNotify)(void **apArg, int nArg),    /* Callback function to invoke */
9127
  void *pNotifyArg                            /* Argument to pass to xNotify */
9128
);
9129
9130
9131
/*
9132
** CAPI3REF: String Comparison
9133
**
9134
** ^The [sqlite3_stricmp()] and [sqlite3_strnicmp()] APIs allow applications
9135
** and extensions to compare the contents of two buffers containing UTF-8
9136
** strings in a case-independent fashion, using the same definition of "case
9137
** independence" that SQLite uses internally when comparing identifiers.
9138
*/
9139
SQLITE_API int sqlite3_stricmp(const char *, const char *);
9140
SQLITE_API int sqlite3_strnicmp(const char *, const char *, int);
9141
9142
/*
9143
** CAPI3REF: String Globbing
9144
*
9145
** ^The [sqlite3_strglob(P,X)] interface returns zero if and only if
9146
** string X matches the [GLOB] pattern P.
9147
** ^The definition of [GLOB] pattern matching used in
9148
** [sqlite3_strglob(P,X)] is the same as for the "X GLOB P" operator in the
9149
** SQL dialect understood by SQLite.  ^The [sqlite3_strglob(P,X)] function
9150
** is case sensitive.
9151
**
9152
** Note that this routine returns zero on a match and non-zero if the strings
9153
** do not match, the same as [sqlite3_stricmp()] and [sqlite3_strnicmp()].
9154
**
9155
** See also: [sqlite3_strlike()].
9156
*/
9157
SQLITE_API int sqlite3_strglob(const char *zGlob, const char *zStr);
9158
9159
/*
9160
** CAPI3REF: String LIKE Matching
9161
*
9162
** ^The [sqlite3_strlike(P,X,E)] interface returns zero if and only if
9163
** string X matches the [LIKE] pattern P with escape character E.
9164
** ^The definition of [LIKE] pattern matching used in
9165
** [sqlite3_strlike(P,X,E)] is the same as for the "X LIKE P ESCAPE E"
9166
** operator in the SQL dialect understood by SQLite.  ^For "X LIKE P" without
9167
** the ESCAPE clause, set the E parameter of [sqlite3_strlike(P,X,E)] to 0.
9168
** ^As with the LIKE operator, the [sqlite3_strlike(P,X,E)] function is case
9169
** insensitive - equivalent upper and lower case ASCII characters match
9170
** one another.
9171
**
9172
** ^The [sqlite3_strlike(P,X,E)] function matches Unicode characters, though
9173
** only ASCII characters are case folded.
9174
**
9175
** Note that this routine returns zero on a match and non-zero if the strings
9176
** do not match, the same as [sqlite3_stricmp()] and [sqlite3_strnicmp()].
9177
**
9178
** See also: [sqlite3_strglob()].
9179
*/
9180
SQLITE_API int sqlite3_strlike(const char *zGlob, const char *zStr, unsigned int cEsc);
9181
9182
/*
9183
** CAPI3REF: Error Logging Interface
9184
**
9185
** ^The [sqlite3_log()] interface writes a message into the [error log]
9186
** established by the [SQLITE_CONFIG_LOG] option to [sqlite3_config()].
9187
** ^If logging is enabled, the zFormat string and subsequent arguments are
9188
** used with [sqlite3_snprintf()] to generate the final output string.
9189
**
9190
** The sqlite3_log() interface is intended for use by extensions such as
9191
** virtual tables, collating functions, and SQL functions.  While there is
9192
** nothing to prevent an application from calling sqlite3_log(), doing so
9193
** is considered bad form.
9194
**
9195
** The zFormat string must not be NULL.
9196
**
9197
** To avoid deadlocks and other threading problems, the sqlite3_log() routine
9198
** will not use dynamically allocated memory.  The log message is stored in
9199
** a fixed-length buffer on the stack.  If the log message is longer than
9200
** a few hundred characters, it will be truncated to the length of the
9201
** buffer.
9202
*/
9203
SQLITE_API void sqlite3_log(int iErrCode, const char *zFormat, ...);
9204
9205
/*
9206
** CAPI3REF: Write-Ahead Log Commit Hook
9207
** METHOD: sqlite3
9208
**
9209
** ^The [sqlite3_wal_hook()] function is used to register a callback that
9210
** is invoked each time data is committed to a database in wal mode.
9211
**
9212
** ^(The callback is invoked by SQLite after the commit has taken place and
9213
** the associated write-lock on the database released)^, so the implementation
9214
** may read, write or [checkpoint] the database as required.
9215
**
9216
** ^The first parameter passed to the callback function when it is invoked
9217
** is a copy of the third parameter passed to sqlite3_wal_hook() when
9218
** registering the callback. ^The second is a copy of the database handle.
9219
** ^The third parameter is the name of the database that was written to -
9220
** either "main" or the name of an [ATTACH]-ed database. ^The fourth parameter
9221
** is the number of pages currently in the write-ahead log file,
9222
** including those that were just committed.
9223
**
9224
** The callback function should normally return [SQLITE_OK].  ^If an error
9225
** code is returned, that error will propagate back up through the
9226
** SQLite code base to cause the statement that provoked the callback
9227
** to report an error, though the commit will have still occurred. If the
9228
** callback returns [SQLITE_ROW] or [SQLITE_DONE], or if it returns a value
9229
** that does not correspond to any valid SQLite error code, the results
9230
** are undefined.
9231
**
9232
** A single database handle may have at most a single write-ahead log callback
9233
** registered at one time. ^Calling [sqlite3_wal_hook()] replaces any
9234
** previously registered write-ahead log callback. ^The return value is
9235
** a copy of the third parameter from the previous call, if any, or 0.
9236
** ^Note that the [sqlite3_wal_autocheckpoint()] interface and the
9237
** [wal_autocheckpoint pragma] both invoke [sqlite3_wal_hook()] and will
9238
** overwrite any prior [sqlite3_wal_hook()] settings.
9239
*/
9240
SQLITE_API void *sqlite3_wal_hook(
9241
  sqlite3*,
9242
  int(*)(void *,sqlite3*,const char*,int),
9243
  void*
9244
);
9245
9246
/*
9247
** CAPI3REF: Configure an auto-checkpoint
9248
** METHOD: sqlite3
9249
**
9250
** ^The [sqlite3_wal_autocheckpoint(D,N)] is a wrapper around
9251
** [sqlite3_wal_hook()] that causes any database on [database connection] D
9252
** to automatically [checkpoint]
9253
** after committing a transaction if there are N or
9254
** more frames in the [write-ahead log] file.  ^Passing zero or
9255
** a negative value as the nFrame parameter disables automatic
9256
** checkpoints entirely.
9257
**
9258
** ^The callback registered by this function replaces any existing callback
9259
** registered using [sqlite3_wal_hook()].  ^Likewise, registering a callback
9260
** using [sqlite3_wal_hook()] disables the automatic checkpoint mechanism
9261
** configured by this function.
9262
**
9263
** ^The [wal_autocheckpoint pragma] can be used to invoke this interface
9264
** from SQL.
9265
**
9266
** ^Checkpoints initiated by this mechanism are
9267
** [sqlite3_wal_checkpoint_v2|PASSIVE].
9268
**
9269
** ^Every new [database connection] defaults to having the auto-checkpoint
9270
** enabled with a threshold of 1000 or [SQLITE_DEFAULT_WAL_AUTOCHECKPOINT]
9271
** pages.  The use of this interface
9272
** is only necessary if the default setting is found to be suboptimal
9273
** for a particular application.
9274
*/
9275
SQLITE_API int sqlite3_wal_autocheckpoint(sqlite3 *db, int N);
9276
9277
/*
9278
** CAPI3REF: Checkpoint a database
9279
** METHOD: sqlite3
9280
**
9281
** ^(The sqlite3_wal_checkpoint(D,X) is equivalent to
9282
** [sqlite3_wal_checkpoint_v2](D,X,[SQLITE_CHECKPOINT_PASSIVE],0,0).)^
9283
**
9284
** In brief, sqlite3_wal_checkpoint(D,X) causes the content in the
9285
** [write-ahead log] for database X on [database connection] D to be
9286
** transferred into the database file and for the write-ahead log to
9287
** be reset.  See the [checkpointing] documentation for addition
9288
** information.
9289
**
9290
** This interface used to be the only way to cause a checkpoint to
9291
** occur.  But then the newer and more powerful [sqlite3_wal_checkpoint_v2()]
9292
** interface was added.  This interface is retained for backwards
9293
** compatibility and as a convenience for applications that need to manually
9294
** start a callback but which do not need the full power (and corresponding
9295
** complication) of [sqlite3_wal_checkpoint_v2()].
9296
*/
9297
SQLITE_API int sqlite3_wal_checkpoint(sqlite3 *db, const char *zDb);
9298
9299
/*
9300
** CAPI3REF: Checkpoint a database
9301
** METHOD: sqlite3
9302
**
9303
** ^(The sqlite3_wal_checkpoint_v2(D,X,M,L,C) interface runs a checkpoint
9304
** operation on database X of [database connection] D in mode M.  Status
9305
** information is written back into integers pointed to by L and C.)^
9306
** ^(The M parameter must be a valid [checkpoint mode]:)^
9307
**
9308
** <dl>
9309
** <dt>SQLITE_CHECKPOINT_PASSIVE<dd>
9310
**   ^Checkpoint as many frames as possible without waiting for any database
9311
**   readers or writers to finish, then sync the database file if all frames
9312
**   in the log were checkpointed. ^The [busy-handler callback]
9313
**   is never invoked in the SQLITE_CHECKPOINT_PASSIVE mode.
9314
**   ^On the other hand, passive mode might leave the checkpoint unfinished
9315
**   if there are concurrent readers or writers.
9316
**
9317
** <dt>SQLITE_CHECKPOINT_FULL<dd>
9318
**   ^This mode blocks (it invokes the
9319
**   [sqlite3_busy_handler|busy-handler callback]) until there is no
9320
**   database writer and all readers are reading from the most recent database
9321
**   snapshot. ^It then checkpoints all frames in the log file and syncs the
9322
**   database file. ^This mode blocks new database writers while it is pending,
9323
**   but new database readers are allowed to continue unimpeded.
9324
**
9325
** <dt>SQLITE_CHECKPOINT_RESTART<dd>
9326
**   ^This mode works the same way as SQLITE_CHECKPOINT_FULL with the addition
9327
**   that after checkpointing the log file it blocks (calls the
9328
**   [busy-handler callback])
9329
**   until all readers are reading from the database file only. ^This ensures
9330
**   that the next writer will restart the log file from the beginning.
9331
**   ^Like SQLITE_CHECKPOINT_FULL, this mode blocks new
9332
**   database writer attempts while it is pending, but does not impede readers.
9333
**
9334
** <dt>SQLITE_CHECKPOINT_TRUNCATE<dd>
9335
**   ^This mode works the same way as SQLITE_CHECKPOINT_RESTART with the
9336
**   addition that it also truncates the log file to zero bytes just prior
9337
**   to a successful return.
9338
** </dl>
9339
**
9340
** ^If pnLog is not NULL, then *pnLog is set to the total number of frames in
9341
** the log file or to -1 if the checkpoint could not run because
9342
** of an error or because the database is not in [WAL mode]. ^If pnCkpt is not
9343
** NULL,then *pnCkpt is set to the total number of checkpointed frames in the
9344
** log file (including any that were already checkpointed before the function
9345
** was called) or to -1 if the checkpoint could not run due to an error or
9346
** because the database is not in WAL mode. ^Note that upon successful
9347
** completion of an SQLITE_CHECKPOINT_TRUNCATE, the log file will have been
9348
** truncated to zero bytes and so both *pnLog and *pnCkpt will be set to zero.
9349
**
9350
** ^All calls obtain an exclusive "checkpoint" lock on the database file. ^If
9351
** any other process is running a checkpoint operation at the same time, the
9352
** lock cannot be obtained and SQLITE_BUSY is returned. ^Even if there is a
9353
** busy-handler configured, it will not be invoked in this case.
9354
**
9355
** ^The SQLITE_CHECKPOINT_FULL, RESTART and TRUNCATE modes also obtain the
9356
** exclusive "writer" lock on the database file. ^If the writer lock cannot be
9357
** obtained immediately, and a busy-handler is configured, it is invoked and
9358
** the writer lock retried until either the busy-handler returns 0 or the lock
9359
** is successfully obtained. ^The busy-handler is also invoked while waiting for
9360
** database readers as described above. ^If the busy-handler returns 0 before
9361
** the writer lock is obtained or while waiting for database readers, the
9362
** checkpoint operation proceeds from that point in the same way as
9363
** SQLITE_CHECKPOINT_PASSIVE - checkpointing as many frames as possible
9364
** without blocking any further. ^SQLITE_BUSY is returned in this case.
9365
**
9366
** ^If parameter zDb is NULL or points to a zero length string, then the
9367
** specified operation is attempted on all WAL databases [attached] to
9368
** [database connection] db.  In this case the
9369
** values written to output parameters *pnLog and *pnCkpt are undefined. ^If
9370
** an SQLITE_BUSY error is encountered when processing one or more of the
9371
** attached WAL databases, the operation is still attempted on any remaining
9372
** attached databases and SQLITE_BUSY is returned at the end. ^If any other
9373
** error occurs while processing an attached database, processing is abandoned
9374
** and the error code is returned to the caller immediately. ^If no error
9375
** (SQLITE_BUSY or otherwise) is encountered while processing the attached
9376
** databases, SQLITE_OK is returned.
9377
**
9378
** ^If database zDb is the name of an attached database that is not in WAL
9379
** mode, SQLITE_OK is returned and both *pnLog and *pnCkpt set to -1. ^If
9380
** zDb is not NULL (or a zero length string) and is not the name of any
9381
** attached database, SQLITE_ERROR is returned to the caller.
9382
**
9383
** ^Unless it returns SQLITE_MISUSE,
9384
** the sqlite3_wal_checkpoint_v2() interface
9385
** sets the error information that is queried by
9386
** [sqlite3_errcode()] and [sqlite3_errmsg()].
9387
**
9388
** ^The [PRAGMA wal_checkpoint] command can be used to invoke this interface
9389
** from SQL.
9390
*/
9391
SQLITE_API int sqlite3_wal_checkpoint_v2(
9392
  sqlite3 *db,                    /* Database handle */
9393
  const char *zDb,                /* Name of attached database (or NULL) */
9394
  int eMode,                      /* SQLITE_CHECKPOINT_* value */
9395
  int *pnLog,                     /* OUT: Size of WAL log in frames */
9396
  int *pnCkpt                     /* OUT: Total number of frames checkpointed */
9397
);
9398
9399
/*
9400
** CAPI3REF: Checkpoint Mode Values
9401
** KEYWORDS: {checkpoint mode}
9402
**
9403
** These constants define all valid values for the "checkpoint mode" passed
9404
** as the third parameter to the [sqlite3_wal_checkpoint_v2()] interface.
9405
** See the [sqlite3_wal_checkpoint_v2()] documentation for details on the
9406
** meaning of each of these checkpoint modes.
9407
*/
9408
#define SQLITE_CHECKPOINT_PASSIVE  0  /* Do as much as possible w/o blocking */
9409
#define SQLITE_CHECKPOINT_FULL     1  /* Wait for writers, then checkpoint */
9410
#define SQLITE_CHECKPOINT_RESTART  2  /* Like FULL but wait for for readers */
9411
#define SQLITE_CHECKPOINT_TRUNCATE 3  /* Like RESTART but also truncate WAL */
9412
9413
/*
9414
** CAPI3REF: Virtual Table Interface Configuration
9415
**
9416
** This function may be called by either the [xConnect] or [xCreate] method
9417
** of a [virtual table] implementation to configure
9418
** various facets of the virtual table interface.
9419
**
9420
** If this interface is invoked outside the context of an xConnect or
9421
** xCreate virtual table method then the behavior is undefined.
9422
**
9423
** In the call sqlite3_vtab_config(D,C,...) the D parameter is the
9424
** [database connection] in which the virtual table is being created and
9425
** which is passed in as the first argument to the [xConnect] or [xCreate]
9426
** method that is invoking sqlite3_vtab_config().  The C parameter is one
9427
** of the [virtual table configuration options].  The presence and meaning
9428
** of parameters after C depend on which [virtual table configuration option]
9429
** is used.
9430
*/
9431
SQLITE_API int sqlite3_vtab_config(sqlite3*, int op, ...);
9432
9433
/*
9434
** CAPI3REF: Virtual Table Configuration Options
9435
** KEYWORDS: {virtual table configuration options}
9436
** KEYWORDS: {virtual table configuration option}
9437
**
9438
** These macros define the various options to the
9439
** [sqlite3_vtab_config()] interface that [virtual table] implementations
9440
** can use to customize and optimize their behavior.
9441
**
9442
** <dl>
9443
** [[SQLITE_VTAB_CONSTRAINT_SUPPORT]]
9444
** <dt>SQLITE_VTAB_CONSTRAINT_SUPPORT</dt>
9445
** <dd>Calls of the form
9446
** [sqlite3_vtab_config](db,SQLITE_VTAB_CONSTRAINT_SUPPORT,X) are supported,
9447
** where X is an integer.  If X is zero, then the [virtual table] whose
9448
** [xCreate] or [xConnect] method invoked [sqlite3_vtab_config()] does not
9449
** support constraints.  In this configuration (which is the default) if
9450
** a call to the [xUpdate] method returns [SQLITE_CONSTRAINT], then the entire
9451
** statement is rolled back as if [ON CONFLICT | OR ABORT] had been
9452
** specified as part of the users SQL statement, regardless of the actual
9453
** ON CONFLICT mode specified.
9454
**
9455
** If X is non-zero, then the virtual table implementation guarantees
9456
** that if [xUpdate] returns [SQLITE_CONSTRAINT], it will do so before
9457
** any modifications to internal or persistent data structures have been made.
9458
** If the [ON CONFLICT] mode is ABORT, FAIL, IGNORE or ROLLBACK, SQLite
9459
** is able to roll back a statement or database transaction, and abandon
9460
** or continue processing the current SQL statement as appropriate.
9461
** If the ON CONFLICT mode is REPLACE and the [xUpdate] method returns
9462
** [SQLITE_CONSTRAINT], SQLite handles this as if the ON CONFLICT mode
9463
** had been ABORT.
9464
**
9465
** Virtual table implementations that are required to handle OR REPLACE
9466
** must do so within the [xUpdate] method. If a call to the
9467
** [sqlite3_vtab_on_conflict()] function indicates that the current ON
9468
** CONFLICT policy is REPLACE, the virtual table implementation should
9469
** silently replace the appropriate rows within the xUpdate callback and
9470
** return SQLITE_OK. Or, if this is not possible, it may return
9471
** SQLITE_CONSTRAINT, in which case SQLite falls back to OR ABORT
9472
** constraint handling.
9473
** </dd>
9474
**
9475
** [[SQLITE_VTAB_DIRECTONLY]]<dt>SQLITE_VTAB_DIRECTONLY</dt>
9476
** <dd>Calls of the form
9477
** [sqlite3_vtab_config](db,SQLITE_VTAB_DIRECTONLY) from within the
9478
** the [xConnect] or [xCreate] methods of a [virtual table] implmentation
9479
** prohibits that virtual table from being used from within triggers and
9480
** views.
9481
** </dd>
9482
**
9483
** [[SQLITE_VTAB_INNOCUOUS]]<dt>SQLITE_VTAB_INNOCUOUS</dt>
9484
** <dd>Calls of the form
9485
** [sqlite3_vtab_config](db,SQLITE_VTAB_INNOCUOUS) from within the
9486
** the [xConnect] or [xCreate] methods of a [virtual table] implmentation
9487
** identify that virtual table as being safe to use from within triggers
9488
** and views.  Conceptually, the SQLITE_VTAB_INNOCUOUS tag means that the
9489
** virtual table can do no serious harm even if it is controlled by a
9490
** malicious hacker.  Developers should avoid setting the SQLITE_VTAB_INNOCUOUS
9491
** flag unless absolutely necessary.
9492
** </dd>
9493
** </dl>
9494
*/
9495
#define SQLITE_VTAB_CONSTRAINT_SUPPORT 1
9496
#define SQLITE_VTAB_INNOCUOUS          2
9497
#define SQLITE_VTAB_DIRECTONLY         3
9498
9499
/*
9500
** CAPI3REF: Determine The Virtual Table Conflict Policy
9501
**
9502
** This function may only be called from within a call to the [xUpdate] method
9503
** of a [virtual table] implementation for an INSERT or UPDATE operation. ^The
9504
** value returned is one of [SQLITE_ROLLBACK], [SQLITE_IGNORE], [SQLITE_FAIL],
9505
** [SQLITE_ABORT], or [SQLITE_REPLACE], according to the [ON CONFLICT] mode
9506
** of the SQL statement that triggered the call to the [xUpdate] method of the
9507
** [virtual table].
9508
*/
9509
SQLITE_API int sqlite3_vtab_on_conflict(sqlite3 *);
9510
9511
/*
9512
** CAPI3REF: Determine If Virtual Table Column Access Is For UPDATE
9513
**
9514
** If the sqlite3_vtab_nochange(X) routine is called within the [xColumn]
9515
** method of a [virtual table], then it might return true if the
9516
** column is being fetched as part of an UPDATE operation during which the
9517
** column value will not change.  The virtual table implementation can use
9518
** this hint as permission to substitute a return value that is less
9519
** expensive to compute and that the corresponding
9520
** [xUpdate] method understands as a "no-change" value.
9521
**
9522
** If the [xColumn] method calls sqlite3_vtab_nochange() and finds that
9523
** the column is not changed by the UPDATE statement, then the xColumn
9524
** method can optionally return without setting a result, without calling
9525
** any of the [sqlite3_result_int|sqlite3_result_xxxxx() interfaces].
9526
** In that case, [sqlite3_value_nochange(X)] will return true for the
9527
** same column in the [xUpdate] method.
9528
**
9529
** The sqlite3_vtab_nochange() routine is an optimization.  Virtual table
9530
** implementations should continue to give a correct answer even if the
9531
** sqlite3_vtab_nochange() interface were to always return false.  In the
9532
** current implementation, the sqlite3_vtab_nochange() interface does always
9533
** returns false for the enhanced [UPDATE FROM] statement.
9534
*/
9535
SQLITE_API int sqlite3_vtab_nochange(sqlite3_context*);
9536
9537
/*
9538
** CAPI3REF: Determine The Collation For a Virtual Table Constraint
9539
** METHOD: sqlite3_index_info
9540
**
9541
** This function may only be called from within a call to the [xBestIndex]
9542
** method of a [virtual table].  This function returns a pointer to a string
9543
** that is the name of the appropriate collation sequence to use for text
9544
** comparisons on the constraint identified by its arguments.
9545
**
9546
** The first argument must be the pointer to the [sqlite3_index_info] object
9547
** that is the first parameter to the xBestIndex() method. The second argument
9548
** must be an index into the aConstraint[] array belonging to the
9549
** sqlite3_index_info structure passed to xBestIndex.
9550
**
9551
** Important:
9552
** The first parameter must be the same pointer that is passed into the
9553
** xBestMethod() method.  The first parameter may not be a pointer to a
9554
** different [sqlite3_index_info] object, even an exact copy.
9555
**
9556
** The return value is computed as follows:
9557
**
9558
** <ol>
9559
** <li><p> If the constraint comes from a WHERE clause expression that contains
9560
**         a [COLLATE operator], then the name of the collation specified by
9561
**         that COLLATE operator is returned.
9562
** <li><p> If there is no COLLATE operator, but the column that is the subject
9563
**         of the constraint specifies an alternative collating sequence via
9564
**         a [COLLATE clause] on the column definition within the CREATE TABLE
9565
**         statement that was passed into [sqlite3_declare_vtab()], then the
9566
**         name of that alternative collating sequence is returned.
9567
** <li><p> Otherwise, "BINARY" is returned.
9568
** </ol>
9569
*/
9570
SQLITE_API SQLITE_EXPERIMENTAL const char *sqlite3_vtab_collation(sqlite3_index_info*,int);
9571
9572
/*
9573
** CAPI3REF: Determine if a virtual table query is DISTINCT
9574
** METHOD: sqlite3_index_info
9575
**
9576
** This API may only be used from within an [xBestIndex|xBestIndex method]
9577
** of a [virtual table] implementation. The result of calling this
9578
** interface from outside of xBestIndex() is undefined and probably harmful.
9579
**
9580
** ^The sqlite3_vtab_distinct() interface returns an integer between 0 and
9581
** 3.  The integer returned by sqlite3_vtab_distinct()
9582
** gives the virtual table additional information about how the query
9583
** planner wants the output to be ordered. As long as the virtual table
9584
** can meet the ordering requirements of the query planner, it may set
9585
** the "orderByConsumed" flag.
9586
**
9587
** <ol><li value="0"><p>
9588
** ^If the sqlite3_vtab_distinct() interface returns 0, that means
9589
** that the query planner needs the virtual table to return all rows in the
9590
** sort order defined by the "nOrderBy" and "aOrderBy" fields of the
9591
** [sqlite3_index_info] object.  This is the default expectation.  If the
9592
** virtual table outputs all rows in sorted order, then it is always safe for
9593
** the xBestIndex method to set the "orderByConsumed" flag, regardless of
9594
** the return value from sqlite3_vtab_distinct().
9595
** <li value="1"><p>
9596
** ^(If the sqlite3_vtab_distinct() interface returns 1, that means
9597
** that the query planner does not need the rows to be returned in sorted order
9598
** as long as all rows with the same values in all columns identified by the
9599
** "aOrderBy" field are adjacent.)^  This mode is used when the query planner
9600
** is doing a GROUP BY.
9601
** <li value="2"><p>
9602
** ^(If the sqlite3_vtab_distinct() interface returns 2, that means
9603
** that the query planner does not need the rows returned in any particular
9604
** order, as long as rows with the same values in all "aOrderBy" columns
9605
** are adjacent.)^  ^(Furthermore, only a single row for each particular
9606
** combination of values in the columns identified by the "aOrderBy" field
9607
** needs to be returned.)^  ^It is always ok for two or more rows with the same
9608
** values in all "aOrderBy" columns to be returned, as long as all such rows
9609
** are adjacent.  ^The virtual table may, if it chooses, omit extra rows
9610
** that have the same value for all columns identified by "aOrderBy".
9611
** ^However omitting the extra rows is optional.
9612
** This mode is used for a DISTINCT query.
9613
** <li value="3"><p>
9614
** ^(If the sqlite3_vtab_distinct() interface returns 3, that means
9615
** that the query planner needs only distinct rows but it does need the
9616
** rows to be sorted.)^ ^The virtual table implementation is free to omit
9617
** rows that are identical in all aOrderBy columns, if it wants to, but
9618
** it is not required to omit any rows.  This mode is used for queries
9619
** that have both DISTINCT and ORDER BY clauses.
9620
** </ol>
9621
**
9622
** ^For the purposes of comparing virtual table output values to see if the
9623
** values are same value for sorting purposes, two NULL values are considered
9624
** to be the same.  In other words, the comparison operator is "IS"
9625
** (or "IS NOT DISTINCT FROM") and not "==".
9626
**
9627
** If a virtual table implementation is unable to meet the requirements
9628
** specified above, then it must not set the "orderByConsumed" flag in the
9629
** [sqlite3_index_info] object or an incorrect answer may result.
9630
**
9631
** ^A virtual table implementation is always free to return rows in any order
9632
** it wants, as long as the "orderByConsumed" flag is not set.  ^When the
9633
** the "orderByConsumed" flag is unset, the query planner will add extra
9634
** [bytecode] to ensure that the final results returned by the SQL query are
9635
** ordered correctly.  The use of the "orderByConsumed" flag and the
9636
** sqlite3_vtab_distinct() interface is merely an optimization.  ^Careful
9637
** use of the sqlite3_vtab_distinct() interface and the "orderByConsumed"
9638
** flag might help queries against a virtual table to run faster.  Being
9639
** overly aggressive and setting the "orderByConsumed" flag when it is not
9640
** valid to do so, on the other hand, might cause SQLite to return incorrect
9641
** results.
9642
*/
9643
SQLITE_API int sqlite3_vtab_distinct(sqlite3_index_info*);
9644
9645
/*
9646
** CAPI3REF: Identify and handle IN constraints in xBestIndex
9647
**
9648
** This interface may only be used from within an
9649
** [xBestIndex|xBestIndex() method] of a [virtual table] implementation.
9650
** The result of invoking this interface from any other context is
9651
** undefined and probably harmful.
9652
**
9653
** ^(A constraint on a virtual table of the form
9654
** "[IN operator|column IN (...)]" is
9655
** communicated to the xBestIndex method as a
9656
** [SQLITE_INDEX_CONSTRAINT_EQ] constraint.)^  If xBestIndex wants to use
9657
** this constraint, it must set the corresponding
9658
** aConstraintUsage[].argvIndex to a postive integer.  ^(Then, under
9659
** the usual mode of handling IN operators, SQLite generates [bytecode]
9660
** that invokes the [xFilter|xFilter() method] once for each value
9661
** on the right-hand side of the IN operator.)^  Thus the virtual table
9662
** only sees a single value from the right-hand side of the IN operator
9663
** at a time.
9664
**
9665
** In some cases, however, it would be advantageous for the virtual
9666
** table to see all values on the right-hand of the IN operator all at
9667
** once.  The sqlite3_vtab_in() interfaces facilitates this in two ways:
9668
**
9669
** <ol>
9670
** <li><p>
9671
**   ^A call to sqlite3_vtab_in(P,N,-1) will return true (non-zero)
9672
**   if and only if the [sqlite3_index_info|P->aConstraint][N] constraint
9673
**   is an [IN operator] that can be processed all at once.  ^In other words,
9674
**   sqlite3_vtab_in() with -1 in the third argument is a mechanism
9675
**   by which the virtual table can ask SQLite if all-at-once processing
9676
**   of the IN operator is even possible.
9677
**
9678
** <li><p>
9679
**   ^A call to sqlite3_vtab_in(P,N,F) with F==1 or F==0 indicates
9680
**   to SQLite that the virtual table does or does not want to process
9681
**   the IN operator all-at-once, respectively.  ^Thus when the third
9682
**   parameter (F) is non-negative, this interface is the mechanism by
9683
**   which the virtual table tells SQLite how it wants to process the
9684
**   IN operator.
9685
** </ol>
9686
**
9687
** ^The sqlite3_vtab_in(P,N,F) interface can be invoked multiple times
9688
** within the same xBestIndex method call.  ^For any given P,N pair,
9689
** the return value from sqlite3_vtab_in(P,N,F) will always be the same
9690
** within the same xBestIndex call.  ^If the interface returns true
9691
** (non-zero), that means that the constraint is an IN operator
9692
** that can be processed all-at-once.  ^If the constraint is not an IN
9693
** operator or cannot be processed all-at-once, then the interface returns
9694
** false.
9695
**
9696
** ^(All-at-once processing of the IN operator is selected if both of the
9697
** following conditions are met:
9698
**
9699
** <ol>
9700
** <li><p> The P->aConstraintUsage[N].argvIndex value is set to a positive
9701
** integer.  This is how the virtual table tells SQLite that it wants to
9702
** use the N-th constraint.
9703
**
9704
** <li><p> The last call to sqlite3_vtab_in(P,N,F) for which F was
9705
** non-negative had F>=1.
9706
** </ol>)^
9707
**
9708
** ^If either or both of the conditions above are false, then SQLite uses
9709
** the traditional one-at-a-time processing strategy for the IN constraint.
9710
** ^If both conditions are true, then the argvIndex-th parameter to the
9711
** xFilter method will be an [sqlite3_value] that appears to be NULL,
9712
** but which can be passed to [sqlite3_vtab_in_first()] and
9713
** [sqlite3_vtab_in_next()] to find all values on the right-hand side
9714
** of the IN constraint.
9715
*/
9716
SQLITE_API int sqlite3_vtab_in(sqlite3_index_info*, int iCons, int bHandle);
9717
9718
/*
9719
** CAPI3REF: Find all elements on the right-hand side of an IN constraint.
9720
**
9721
** These interfaces are only useful from within the
9722
** [xFilter|xFilter() method] of a [virtual table] implementation.
9723
** The result of invoking these interfaces from any other context
9724
** is undefined and probably harmful.
9725
**
9726
** The X parameter in a call to sqlite3_vtab_in_first(X,P) or
9727
** sqlite3_vtab_in_next(X,P) must be one of the parameters to the
9728
** xFilter method which invokes these routines, and specifically
9729
** a parameter that was previously selected for all-at-once IN constraint
9730
** processing use the [sqlite3_vtab_in()] interface in the
9731
** [xBestIndex|xBestIndex method].  ^(If the X parameter is not
9732
** an xFilter argument that was selected for all-at-once IN constraint
9733
** processing, then these routines return [SQLITE_MISUSE])^ or perhaps
9734
** exhibit some other undefined or harmful behavior.
9735
**
9736
** ^(Use these routines to access all values on the right-hand side
9737
** of the IN constraint using code like the following:
9738
**
9739
** <blockquote><pre>
9740
** &nbsp;  for(rc=sqlite3_vtab_in_first(pList, &pVal);
9741
** &nbsp;      rc==SQLITE_OK && pVal
9742
** &nbsp;      rc=sqlite3_vtab_in_next(pList, &pVal)
9743
** &nbsp;  ){
9744
** &nbsp;    // do something with pVal
9745
** &nbsp;  }
9746
** &nbsp;  if( rc!=SQLITE_OK ){
9747
** &nbsp;    // an error has occurred
9748
** &nbsp;  }
9749
** </pre></blockquote>)^
9750
**
9751
** ^On success, the sqlite3_vtab_in_first(X,P) and sqlite3_vtab_in_next(X,P)
9752
** routines return SQLITE_OK and set *P to point to the first or next value
9753
** on the RHS of the IN constraint.  ^If there are no more values on the
9754
** right hand side of the IN constraint, then *P is set to NULL and these
9755
** routines return [SQLITE_DONE].  ^The return value might be
9756
** some other value, such as SQLITE_NOMEM, in the event of a malfunction.
9757
**
9758
** The *ppOut values returned by these routines are only valid until the
9759
** next call to either of these routines or until the end of the xFilter
9760
** method from which these routines were called.  If the virtual table
9761
** implementation needs to retain the *ppOut values for longer, it must make
9762
** copies.  The *ppOut values are [protected sqlite3_value|protected].
9763
*/
9764
SQLITE_API int sqlite3_vtab_in_first(sqlite3_value *pVal, sqlite3_value **ppOut);
9765
SQLITE_API int sqlite3_vtab_in_next(sqlite3_value *pVal, sqlite3_value **ppOut);
9766
9767
/*
9768
** CAPI3REF: Constraint values in xBestIndex()
9769
** METHOD: sqlite3_index_info
9770
**
9771
** This API may only be used from within the [xBestIndex|xBestIndex method]
9772
** of a [virtual table] implementation. The result of calling this interface
9773
** from outside of an xBestIndex method are undefined and probably harmful.
9774
**
9775
** ^When the sqlite3_vtab_rhs_value(P,J,V) interface is invoked from within
9776
** the [xBestIndex] method of a [virtual table] implementation, with P being
9777
** a copy of the [sqlite3_index_info] object pointer passed into xBestIndex and
9778
** J being a 0-based index into P->aConstraint[], then this routine
9779
** attempts to set *V to the value of the right-hand operand of
9780
** that constraint if the right-hand operand is known.  ^If the
9781
** right-hand operand is not known, then *V is set to a NULL pointer.
9782
** ^The sqlite3_vtab_rhs_value(P,J,V) interface returns SQLITE_OK if
9783
** and only if *V is set to a value.  ^The sqlite3_vtab_rhs_value(P,J,V)
9784
** inteface returns SQLITE_NOTFOUND if the right-hand side of the J-th
9785
** constraint is not available.  ^The sqlite3_vtab_rhs_value() interface
9786
** can return an result code other than SQLITE_OK or SQLITE_NOTFOUND if
9787
** something goes wrong.
9788
**
9789
** The sqlite3_vtab_rhs_value() interface is usually only successful if
9790
** the right-hand operand of a constraint is a literal value in the original
9791
** SQL statement.  If the right-hand operand is an expression or a reference
9792
** to some other column or a [host parameter], then sqlite3_vtab_rhs_value()
9793
** will probably return [SQLITE_NOTFOUND].
9794
**
9795
** ^(Some constraints, such as [SQLITE_INDEX_CONSTRAINT_ISNULL] and
9796
** [SQLITE_INDEX_CONSTRAINT_ISNOTNULL], have no right-hand operand.  For such
9797
** constraints, sqlite3_vtab_rhs_value() always returns SQLITE_NOTFOUND.)^
9798
**
9799
** ^The [sqlite3_value] object returned in *V is a protected sqlite3_value
9800
** and remains valid for the duration of the xBestIndex method call.
9801
** ^When xBestIndex returns, the sqlite3_value object returned by
9802
** sqlite3_vtab_rhs_value() is automatically deallocated.
9803
**
9804
** The "_rhs_" in the name of this routine is an abbreviation for
9805
** "Right-Hand Side".
9806
*/
9807
SQLITE_API int sqlite3_vtab_rhs_value(sqlite3_index_info*, int, sqlite3_value **ppVal);
9808
9809
/*
9810
** CAPI3REF: Conflict resolution modes
9811
** KEYWORDS: {conflict resolution mode}
9812
**
9813
** These constants are returned by [sqlite3_vtab_on_conflict()] to
9814
** inform a [virtual table] implementation what the [ON CONFLICT] mode
9815
** is for the SQL statement being evaluated.
9816
**
9817
** Note that the [SQLITE_IGNORE] constant is also used as a potential
9818
** return value from the [sqlite3_set_authorizer()] callback and that
9819
** [SQLITE_ABORT] is also a [result code].
9820
*/
9821
#define SQLITE_ROLLBACK 1
9822
/* #define SQLITE_IGNORE 2 // Also used by sqlite3_authorizer() callback */
9823
#define SQLITE_FAIL     3
9824
/* #define SQLITE_ABORT 4  // Also an error code */
9825
#define SQLITE_REPLACE  5
9826
9827
/*
9828
** CAPI3REF: Prepared Statement Scan Status Opcodes
9829
** KEYWORDS: {scanstatus options}
9830
**
9831
** The following constants can be used for the T parameter to the
9832
** [sqlite3_stmt_scanstatus(S,X,T,V)] interface.  Each constant designates a
9833
** different metric for sqlite3_stmt_scanstatus() to return.
9834
**
9835
** When the value returned to V is a string, space to hold that string is
9836
** managed by the prepared statement S and will be automatically freed when
9837
** S is finalized.
9838
**
9839
** <dl>
9840
** [[SQLITE_SCANSTAT_NLOOP]] <dt>SQLITE_SCANSTAT_NLOOP</dt>
9841
** <dd>^The [sqlite3_int64] variable pointed to by the V parameter will be
9842
** set to the total number of times that the X-th loop has run.</dd>
9843
**
9844
** [[SQLITE_SCANSTAT_NVISIT]] <dt>SQLITE_SCANSTAT_NVISIT</dt>
9845
** <dd>^The [sqlite3_int64] variable pointed to by the V parameter will be set
9846
** to the total number of rows examined by all iterations of the X-th loop.</dd>
9847
**
9848
** [[SQLITE_SCANSTAT_EST]] <dt>SQLITE_SCANSTAT_EST</dt>
9849
** <dd>^The "double" variable pointed to by the V parameter will be set to the
9850
** query planner's estimate for the average number of rows output from each
9851
** iteration of the X-th loop.  If the query planner's estimates was accurate,
9852
** then this value will approximate the quotient NVISIT/NLOOP and the
9853
** product of this value for all prior loops with the same SELECTID will
9854
** be the NLOOP value for the current loop.
9855
**
9856
** [[SQLITE_SCANSTAT_NAME]] <dt>SQLITE_SCANSTAT_NAME</dt>
9857
** <dd>^The "const char *" variable pointed to by the V parameter will be set
9858
** to a zero-terminated UTF-8 string containing the name of the index or table
9859
** used for the X-th loop.
9860
**
9861
** [[SQLITE_SCANSTAT_EXPLAIN]] <dt>SQLITE_SCANSTAT_EXPLAIN</dt>
9862
** <dd>^The "const char *" variable pointed to by the V parameter will be set
9863
** to a zero-terminated UTF-8 string containing the [EXPLAIN QUERY PLAN]
9864
** description for the X-th loop.
9865
**
9866
** [[SQLITE_SCANSTAT_SELECTID]] <dt>SQLITE_SCANSTAT_SELECT</dt>
9867
** <dd>^The "int" variable pointed to by the V parameter will be set to the
9868
** "select-id" for the X-th loop.  The select-id identifies which query or
9869
** subquery the loop is part of.  The main query has a select-id of zero.
9870
** The select-id is the same value as is output in the first column
9871
** of an [EXPLAIN QUERY PLAN] query.
9872
** </dl>
9873
*/
9874
#define SQLITE_SCANSTAT_NLOOP    0
9875
#define SQLITE_SCANSTAT_NVISIT   1
9876
#define SQLITE_SCANSTAT_EST      2
9877
#define SQLITE_SCANSTAT_NAME     3
9878
#define SQLITE_SCANSTAT_EXPLAIN  4
9879
#define SQLITE_SCANSTAT_SELECTID 5
9880
9881
/*
9882
** CAPI3REF: Prepared Statement Scan Status
9883
** METHOD: sqlite3_stmt
9884
**
9885
** This interface returns information about the predicted and measured
9886
** performance for pStmt.  Advanced applications can use this
9887
** interface to compare the predicted and the measured performance and
9888
** issue warnings and/or rerun [ANALYZE] if discrepancies are found.
9889
**
9890
** Since this interface is expected to be rarely used, it is only
9891
** available if SQLite is compiled using the [SQLITE_ENABLE_STMT_SCANSTATUS]
9892
** compile-time option.
9893
**
9894
** The "iScanStatusOp" parameter determines which status information to return.
9895
** The "iScanStatusOp" must be one of the [scanstatus options] or the behavior
9896
** of this interface is undefined.
9897
** ^The requested measurement is written into a variable pointed to by
9898
** the "pOut" parameter.
9899
** Parameter "idx" identifies the specific loop to retrieve statistics for.
9900
** Loops are numbered starting from zero. ^If idx is out of range - less than
9901
** zero or greater than or equal to the total number of loops used to implement
9902
** the statement - a non-zero value is returned and the variable that pOut
9903
** points to is unchanged.
9904
**
9905
** ^Statistics might not be available for all loops in all statements. ^In cases
9906
** where there exist loops with no available statistics, this function behaves
9907
** as if the loop did not exist - it returns non-zero and leave the variable
9908
** that pOut points to unchanged.
9909
**
9910
** See also: [sqlite3_stmt_scanstatus_reset()]
9911
*/
9912
SQLITE_API int sqlite3_stmt_scanstatus(
9913
  sqlite3_stmt *pStmt,      /* Prepared statement for which info desired */
9914
  int idx,                  /* Index of loop to report on */
9915
  int iScanStatusOp,        /* Information desired.  SQLITE_SCANSTAT_* */
9916
  void *pOut                /* Result written here */
9917
);
9918
9919
/*
9920
** CAPI3REF: Zero Scan-Status Counters
9921
** METHOD: sqlite3_stmt
9922
**
9923
** ^Zero all [sqlite3_stmt_scanstatus()] related event counters.
9924
**
9925
** This API is only available if the library is built with pre-processor
9926
** symbol [SQLITE_ENABLE_STMT_SCANSTATUS] defined.
9927
*/
9928
SQLITE_API void sqlite3_stmt_scanstatus_reset(sqlite3_stmt*);
9929
9930
/*
9931
** CAPI3REF: Flush caches to disk mid-transaction
9932
** METHOD: sqlite3
9933
**
9934
** ^If a write-transaction is open on [database connection] D when the
9935
** [sqlite3_db_cacheflush(D)] interface invoked, any dirty
9936
** pages in the pager-cache that are not currently in use are written out
9937
** to disk. A dirty page may be in use if a database cursor created by an
9938
** active SQL statement is reading from it, or if it is page 1 of a database
9939
** file (page 1 is always "in use").  ^The [sqlite3_db_cacheflush(D)]
9940
** interface flushes caches for all schemas - "main", "temp", and
9941
** any [attached] databases.
9942
**
9943
** ^If this function needs to obtain extra database locks before dirty pages
9944
** can be flushed to disk, it does so. ^If those locks cannot be obtained
9945
** immediately and there is a busy-handler callback configured, it is invoked
9946
** in the usual manner. ^If the required lock still cannot be obtained, then
9947
** the database is skipped and an attempt made to flush any dirty pages
9948
** belonging to the next (if any) database. ^If any databases are skipped
9949
** because locks cannot be obtained, but no other error occurs, this
9950
** function returns SQLITE_BUSY.
9951
**
9952
** ^If any other error occurs while flushing dirty pages to disk (for
9953
** example an IO error or out-of-memory condition), then processing is
9954
** abandoned and an SQLite [error code] is returned to the caller immediately.
9955
**
9956
** ^Otherwise, if no error occurs, [sqlite3_db_cacheflush()] returns SQLITE_OK.
9957
**
9958
** ^This function does not set the database handle error code or message
9959
** returned by the [sqlite3_errcode()] and [sqlite3_errmsg()] functions.
9960
*/
9961
SQLITE_API int sqlite3_db_cacheflush(sqlite3*);
9962
9963
/*
9964
** CAPI3REF: The pre-update hook.
9965
** METHOD: sqlite3
9966
**
9967
** ^These interfaces are only available if SQLite is compiled using the
9968
** [SQLITE_ENABLE_PREUPDATE_HOOK] compile-time option.
9969
**
9970
** ^The [sqlite3_preupdate_hook()] interface registers a callback function
9971
** that is invoked prior to each [INSERT], [UPDATE], and [DELETE] operation
9972
** on a database table.
9973
** ^At most one preupdate hook may be registered at a time on a single
9974
** [database connection]; each call to [sqlite3_preupdate_hook()] overrides
9975
** the previous setting.
9976
** ^The preupdate hook is disabled by invoking [sqlite3_preupdate_hook()]
9977
** with a NULL pointer as the second parameter.
9978
** ^The third parameter to [sqlite3_preupdate_hook()] is passed through as
9979
** the first parameter to callbacks.
9980
**
9981
** ^The preupdate hook only fires for changes to real database tables; the
9982
** preupdate hook is not invoked for changes to [virtual tables] or to
9983
** system tables like sqlite_sequence or sqlite_stat1.
9984
**
9985
** ^The second parameter to the preupdate callback is a pointer to
9986
** the [database connection] that registered the preupdate hook.
9987
** ^The third parameter to the preupdate callback is one of the constants
9988
** [SQLITE_INSERT], [SQLITE_DELETE], or [SQLITE_UPDATE] to identify the
9989
** kind of update operation that is about to occur.
9990
** ^(The fourth parameter to the preupdate callback is the name of the
9991
** database within the database connection that is being modified.  This
9992
** will be "main" for the main database or "temp" for TEMP tables or
9993
** the name given after the AS keyword in the [ATTACH] statement for attached
9994
** databases.)^
9995
** ^The fifth parameter to the preupdate callback is the name of the
9996
** table that is being modified.
9997
**
9998
** For an UPDATE or DELETE operation on a [rowid table], the sixth
9999
** parameter passed to the preupdate callback is the initial [rowid] of the
10000
** row being modified or deleted. For an INSERT operation on a rowid table,
10001
** or any operation on a WITHOUT ROWID table, the value of the sixth
10002
** parameter is undefined. For an INSERT or UPDATE on a rowid table the
10003
** seventh parameter is the final rowid value of the row being inserted
10004
** or updated. The value of the seventh parameter passed to the callback
10005
** function is not defined for operations on WITHOUT ROWID tables, or for
10006
** DELETE operations on rowid tables.
10007
**
10008
** The [sqlite3_preupdate_old()], [sqlite3_preupdate_new()],
10009
** [sqlite3_preupdate_count()], and [sqlite3_preupdate_depth()] interfaces
10010
** provide additional information about a preupdate event. These routines
10011
** may only be called from within a preupdate callback.  Invoking any of
10012
** these routines from outside of a preupdate callback or with a
10013
** [database connection] pointer that is different from the one supplied
10014
** to the preupdate callback results in undefined and probably undesirable
10015
** behavior.
10016
**
10017
** ^The [sqlite3_preupdate_count(D)] interface returns the number of columns
10018
** in the row that is being inserted, updated, or deleted.
10019
**
10020
** ^The [sqlite3_preupdate_old(D,N,P)] interface writes into P a pointer to
10021
** a [protected sqlite3_value] that contains the value of the Nth column of
10022
** the table row before it is updated.  The N parameter must be between 0
10023
** and one less than the number of columns or the behavior will be
10024
** undefined. This must only be used within SQLITE_UPDATE and SQLITE_DELETE
10025
** preupdate callbacks; if it is used by an SQLITE_INSERT callback then the
10026
** behavior is undefined.  The [sqlite3_value] that P points to
10027
** will be destroyed when the preupdate callback returns.
10028
**
10029
** ^The [sqlite3_preupdate_new(D,N,P)] interface writes into P a pointer to
10030
** a [protected sqlite3_value] that contains the value of the Nth column of
10031
** the table row after it is updated.  The N parameter must be between 0
10032
** and one less than the number of columns or the behavior will be
10033
** undefined. This must only be used within SQLITE_INSERT and SQLITE_UPDATE
10034
** preupdate callbacks; if it is used by an SQLITE_DELETE callback then the
10035
** behavior is undefined.  The [sqlite3_value] that P points to
10036
** will be destroyed when the preupdate callback returns.
10037
**
10038
** ^The [sqlite3_preupdate_depth(D)] interface returns 0 if the preupdate
10039
** callback was invoked as a result of a direct insert, update, or delete
10040
** operation; or 1 for inserts, updates, or deletes invoked by top-level
10041
** triggers; or 2 for changes resulting from triggers called by top-level
10042
** triggers; and so forth.
10043
**
10044
** When the [sqlite3_blob_write()] API is used to update a blob column,
10045
** the pre-update hook is invoked with SQLITE_DELETE. This is because the
10046
** in this case the new values are not available. In this case, when a
10047
** callback made with op==SQLITE_DELETE is actuall a write using the
10048
** sqlite3_blob_write() API, the [sqlite3_preupdate_blobwrite()] returns
10049
** the index of the column being written. In other cases, where the
10050
** pre-update hook is being invoked for some other reason, including a
10051
** regular DELETE, sqlite3_preupdate_blobwrite() returns -1.
10052
**
10053
** See also:  [sqlite3_update_hook()]
10054
*/
10055
#if defined(SQLITE_ENABLE_PREUPDATE_HOOK)
10056
SQLITE_API void *sqlite3_preupdate_hook(
10057
  sqlite3 *db,
10058
  void(*xPreUpdate)(
10059
    void *pCtx,                   /* Copy of third arg to preupdate_hook() */
10060
    sqlite3 *db,                  /* Database handle */
10061
    int op,                       /* SQLITE_UPDATE, DELETE or INSERT */
10062
    char const *zDb,              /* Database name */
10063
    char const *zName,            /* Table name */
10064
    sqlite3_int64 iKey1,          /* Rowid of row about to be deleted/updated */
10065
    sqlite3_int64 iKey2           /* New rowid value (for a rowid UPDATE) */
10066
  ),
10067
  void*
10068
);
10069
SQLITE_API int sqlite3_preupdate_old(sqlite3 *, int, sqlite3_value **);
10070
SQLITE_API int sqlite3_preupdate_count(sqlite3 *);
10071
SQLITE_API int sqlite3_preupdate_depth(sqlite3 *);
10072
SQLITE_API int sqlite3_preupdate_new(sqlite3 *, int, sqlite3_value **);
10073
SQLITE_API int sqlite3_preupdate_blobwrite(sqlite3 *);
10074
#endif
10075
10076
/*
10077
** CAPI3REF: Low-level system error code
10078
** METHOD: sqlite3
10079
**
10080
** ^Attempt to return the underlying operating system error code or error
10081
** number that caused the most recent I/O error or failure to open a file.
10082
** The return value is OS-dependent.  For example, on unix systems, after
10083
** [sqlite3_open_v2()] returns [SQLITE_CANTOPEN], this interface could be
10084
** called to get back the underlying "errno" that caused the problem, such
10085
** as ENOSPC, EAUTH, EISDIR, and so forth.
10086
*/
10087
SQLITE_API int sqlite3_system_errno(sqlite3*);
10088
10089
/*
10090
** CAPI3REF: Database Snapshot
10091
** KEYWORDS: {snapshot} {sqlite3_snapshot}
10092
**
10093
** An instance of the snapshot object records the state of a [WAL mode]
10094
** database for some specific point in history.
10095
**
10096
** In [WAL mode], multiple [database connections] that are open on the
10097
** same database file can each be reading a different historical version
10098
** of the database file.  When a [database connection] begins a read
10099
** transaction, that connection sees an unchanging copy of the database
10100
** as it existed for the point in time when the transaction first started.
10101
** Subsequent changes to the database from other connections are not seen
10102
** by the reader until a new read transaction is started.
10103
**
10104
** The sqlite3_snapshot object records state information about an historical
10105
** version of the database file so that it is possible to later open a new read
10106
** transaction that sees that historical version of the database rather than
10107
** the most recent version.
10108
*/
10109
typedef struct sqlite3_snapshot {
10110
  unsigned char hidden[48];
10111
} sqlite3_snapshot;
10112
10113
/*
10114
** CAPI3REF: Record A Database Snapshot
10115
** CONSTRUCTOR: sqlite3_snapshot
10116
**
10117
** ^The [sqlite3_snapshot_get(D,S,P)] interface attempts to make a
10118
** new [sqlite3_snapshot] object that records the current state of
10119
** schema S in database connection D.  ^On success, the
10120
** [sqlite3_snapshot_get(D,S,P)] interface writes a pointer to the newly
10121
** created [sqlite3_snapshot] object into *P and returns SQLITE_OK.
10122
** If there is not already a read-transaction open on schema S when
10123
** this function is called, one is opened automatically.
10124
**
10125
** The following must be true for this function to succeed. If any of
10126
** the following statements are false when sqlite3_snapshot_get() is
10127
** called, SQLITE_ERROR is returned. The final value of *P is undefined
10128
** in this case.
10129
**
10130
** <ul>
10131
**   <li> The database handle must not be in [autocommit mode].
10132
**
10133
**   <li> Schema S of [database connection] D must be a [WAL mode] database.
10134
**
10135
**   <li> There must not be a write transaction open on schema S of database
10136
**        connection D.
10137
**
10138
**   <li> One or more transactions must have been written to the current wal
10139
**        file since it was created on disk (by any connection). This means
10140
**        that a snapshot cannot be taken on a wal mode database with no wal
10141
**        file immediately after it is first opened. At least one transaction
10142
**        must be written to it first.
10143
** </ul>
10144
**
10145
** This function may also return SQLITE_NOMEM.  If it is called with the
10146
** database handle in autocommit mode but fails for some other reason,
10147
** whether or not a read transaction is opened on schema S is undefined.
10148
**
10149
** The [sqlite3_snapshot] object returned from a successful call to
10150
** [sqlite3_snapshot_get()] must be freed using [sqlite3_snapshot_free()]
10151
** to avoid a memory leak.
10152
**
10153
** The [sqlite3_snapshot_get()] interface is only available when the
10154
** [SQLITE_ENABLE_SNAPSHOT] compile-time option is used.
10155
*/
10156
SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_snapshot_get(
10157
  sqlite3 *db,
10158
  const char *zSchema,
10159
  sqlite3_snapshot **ppSnapshot
10160
);
10161
10162
/*
10163
** CAPI3REF: Start a read transaction on an historical snapshot
10164
** METHOD: sqlite3_snapshot
10165
**
10166
** ^The [sqlite3_snapshot_open(D,S,P)] interface either starts a new read
10167
** transaction or upgrades an existing one for schema S of
10168
** [database connection] D such that the read transaction refers to
10169
** historical [snapshot] P, rather than the most recent change to the
10170
** database. ^The [sqlite3_snapshot_open()] interface returns SQLITE_OK
10171
** on success or an appropriate [error code] if it fails.
10172
**
10173
** ^In order to succeed, the database connection must not be in
10174
** [autocommit mode] when [sqlite3_snapshot_open(D,S,P)] is called. If there
10175
** is already a read transaction open on schema S, then the database handle
10176
** must have no active statements (SELECT statements that have been passed
10177
** to sqlite3_step() but not sqlite3_reset() or sqlite3_finalize()).
10178
** SQLITE_ERROR is returned if either of these conditions is violated, or
10179
** if schema S does not exist, or if the snapshot object is invalid.
10180
**
10181
** ^A call to sqlite3_snapshot_open() will fail to open if the specified
10182
** snapshot has been overwritten by a [checkpoint]. In this case
10183
** SQLITE_ERROR_SNAPSHOT is returned.
10184
**
10185
** If there is already a read transaction open when this function is
10186
** invoked, then the same read transaction remains open (on the same
10187
** database snapshot) if SQLITE_ERROR, SQLITE_BUSY or SQLITE_ERROR_SNAPSHOT
10188
** is returned. If another error code - for example SQLITE_PROTOCOL or an
10189
** SQLITE_IOERR error code - is returned, then the final state of the
10190
** read transaction is undefined. If SQLITE_OK is returned, then the
10191
** read transaction is now open on database snapshot P.
10192
**
10193
** ^(A call to [sqlite3_snapshot_open(D,S,P)] will fail if the
10194
** database connection D does not know that the database file for
10195
** schema S is in [WAL mode].  A database connection might not know
10196
** that the database file is in [WAL mode] if there has been no prior
10197
** I/O on that database connection, or if the database entered [WAL mode]
10198
** after the most recent I/O on the database connection.)^
10199
** (Hint: Run "[PRAGMA application_id]" against a newly opened
10200
** database connection in order to make it ready to use snapshots.)
10201
**
10202
** The [sqlite3_snapshot_open()] interface is only available when the
10203
** [SQLITE_ENABLE_SNAPSHOT] compile-time option is used.
10204
*/
10205
SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_snapshot_open(
10206
  sqlite3 *db,
10207
  const char *zSchema,
10208
  sqlite3_snapshot *pSnapshot
10209
);
10210
10211
/*
10212
** CAPI3REF: Destroy a snapshot
10213
** DESTRUCTOR: sqlite3_snapshot
10214
**
10215
** ^The [sqlite3_snapshot_free(P)] interface destroys [sqlite3_snapshot] P.
10216
** The application must eventually free every [sqlite3_snapshot] object
10217
** using this routine to avoid a memory leak.
10218
**
10219
** The [sqlite3_snapshot_free()] interface is only available when the
10220
** [SQLITE_ENABLE_SNAPSHOT] compile-time option is used.
10221
*/
10222
SQLITE_API SQLITE_EXPERIMENTAL void sqlite3_snapshot_free(sqlite3_snapshot*);
10223
10224
/*
10225
** CAPI3REF: Compare the ages of two snapshot handles.
10226
** METHOD: sqlite3_snapshot
10227
**
10228
** The sqlite3_snapshot_cmp(P1, P2) interface is used to compare the ages
10229
** of two valid snapshot handles.
10230
**
10231
** If the two snapshot handles are not associated with the same database
10232
** file, the result of the comparison is undefined.
10233
**
10234
** Additionally, the result of the comparison is only valid if both of the
10235
** snapshot handles were obtained by calling sqlite3_snapshot_get() since the
10236
** last time the wal file was deleted. The wal file is deleted when the
10237
** database is changed back to rollback mode or when the number of database
10238
** clients drops to zero. If either snapshot handle was obtained before the
10239
** wal file was last deleted, the value returned by this function
10240
** is undefined.
10241
**
10242
** Otherwise, this API returns a negative value if P1 refers to an older
10243
** snapshot than P2, zero if the two handles refer to the same database
10244
** snapshot, and a positive value if P1 is a newer snapshot than P2.
10245
**
10246
** This interface is only available if SQLite is compiled with the
10247
** [SQLITE_ENABLE_SNAPSHOT] option.
10248
*/
10249
SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_snapshot_cmp(
10250
  sqlite3_snapshot *p1,
10251
  sqlite3_snapshot *p2
10252
);
10253
10254
/*
10255
** CAPI3REF: Recover snapshots from a wal file
10256
** METHOD: sqlite3_snapshot
10257
**
10258
** If a [WAL file] remains on disk after all database connections close
10259
** (either through the use of the [SQLITE_FCNTL_PERSIST_WAL] [file control]
10260
** or because the last process to have the database opened exited without
10261
** calling [sqlite3_close()]) and a new connection is subsequently opened
10262
** on that database and [WAL file], the [sqlite3_snapshot_open()] interface
10263
** will only be able to open the last transaction added to the WAL file
10264
** even though the WAL file contains other valid transactions.
10265
**
10266
** This function attempts to scan the WAL file associated with database zDb
10267
** of database handle db and make all valid snapshots available to
10268
** sqlite3_snapshot_open(). It is an error if there is already a read
10269
** transaction open on the database, or if the database is not a WAL mode
10270
** database.
10271
**
10272
** SQLITE_OK is returned if successful, or an SQLite error code otherwise.
10273
**
10274
** This interface is only available if SQLite is compiled with the
10275
** [SQLITE_ENABLE_SNAPSHOT] option.
10276
*/
10277
SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_snapshot_recover(sqlite3 *db, const char *zDb);
10278
10279
/*
10280
** CAPI3REF: Serialize a database
10281
**
10282
** The sqlite3_serialize(D,S,P,F) interface returns a pointer to memory
10283
** that is a serialization of the S database on [database connection] D.
10284
** If P is not a NULL pointer, then the size of the database in bytes
10285
** is written into *P.
10286
**
10287
** For an ordinary on-disk database file, the serialization is just a
10288
** copy of the disk file.  For an in-memory database or a "TEMP" database,
10289
** the serialization is the same sequence of bytes which would be written
10290
** to disk if that database where backed up to disk.
10291
**
10292
** The usual case is that sqlite3_serialize() copies the serialization of
10293
** the database into memory obtained from [sqlite3_malloc64()] and returns
10294
** a pointer to that memory.  The caller is responsible for freeing the
10295
** returned value to avoid a memory leak.  However, if the F argument
10296
** contains the SQLITE_SERIALIZE_NOCOPY bit, then no memory allocations
10297
** are made, and the sqlite3_serialize() function will return a pointer
10298
** to the contiguous memory representation of the database that SQLite
10299
** is currently using for that database, or NULL if the no such contiguous
10300
** memory representation of the database exists.  A contiguous memory
10301
** representation of the database will usually only exist if there has
10302
** been a prior call to [sqlite3_deserialize(D,S,...)] with the same
10303
** values of D and S.
10304
** The size of the database is written into *P even if the
10305
** SQLITE_SERIALIZE_NOCOPY bit is set but no contiguous copy
10306
** of the database exists.
10307
**
10308
** A call to sqlite3_serialize(D,S,P,F) might return NULL even if the
10309
** SQLITE_SERIALIZE_NOCOPY bit is omitted from argument F if a memory
10310
** allocation error occurs.
10311
**
10312
** This interface is omitted if SQLite is compiled with the
10313
** [SQLITE_OMIT_DESERIALIZE] option.
10314
*/
10315
SQLITE_API unsigned char *sqlite3_serialize(
10316
  sqlite3 *db,           /* The database connection */
10317
  const char *zSchema,   /* Which DB to serialize. ex: "main", "temp", ... */
10318
  sqlite3_int64 *piSize, /* Write size of the DB here, if not NULL */
10319
  unsigned int mFlags    /* Zero or more SQLITE_SERIALIZE_* flags */
10320
);
10321
10322
/*
10323
** CAPI3REF: Flags for sqlite3_serialize
10324
**
10325
** Zero or more of the following constants can be OR-ed together for
10326
** the F argument to [sqlite3_serialize(D,S,P,F)].
10327
**
10328
** SQLITE_SERIALIZE_NOCOPY means that [sqlite3_serialize()] will return
10329
** a pointer to contiguous in-memory database that it is currently using,
10330
** without making a copy of the database.  If SQLite is not currently using
10331
** a contiguous in-memory database, then this option causes
10332
** [sqlite3_serialize()] to return a NULL pointer.  SQLite will only be
10333
** using a contiguous in-memory database if it has been initialized by a
10334
** prior call to [sqlite3_deserialize()].
10335
*/
10336
3
#define SQLITE_SERIALIZE_NOCOPY 0x001   /* Do no memory allocations */
10337
10338
/*
10339
** CAPI3REF: Deserialize a database
10340
**
10341
** The sqlite3_deserialize(D,S,P,N,M,F) interface causes the
10342
** [database connection] D to disconnect from database S and then
10343
** reopen S as an in-memory database based on the serialization contained
10344
** in P.  The serialized database P is N bytes in size.  M is the size of
10345
** the buffer P, which might be larger than N.  If M is larger than N, and
10346
** the SQLITE_DESERIALIZE_READONLY bit is not set in F, then SQLite is
10347
** permitted to add content to the in-memory database as long as the total
10348
** size does not exceed M bytes.
10349
**
10350
** If the SQLITE_DESERIALIZE_FREEONCLOSE bit is set in F, then SQLite will
10351
** invoke sqlite3_free() on the serialization buffer when the database
10352
** connection closes.  If the SQLITE_DESERIALIZE_RESIZEABLE bit is set, then
10353
** SQLite will try to increase the buffer size using sqlite3_realloc64()
10354
** if writes on the database cause it to grow larger than M bytes.
10355
**
10356
** The sqlite3_deserialize() interface will fail with SQLITE_BUSY if the
10357
** database is currently in a read transaction or is involved in a backup
10358
** operation.
10359
**
10360
** It is not possible to deserialized into the TEMP database.  If the
10361
** S argument to sqlite3_deserialize(D,S,P,N,M,F) is "temp" then the
10362
** function returns SQLITE_ERROR.
10363
**
10364
** If sqlite3_deserialize(D,S,P,N,M,F) fails for any reason and if the
10365
** SQLITE_DESERIALIZE_FREEONCLOSE bit is set in argument F, then
10366
** [sqlite3_free()] is invoked on argument P prior to returning.
10367
**
10368
** This interface is omitted if SQLite is compiled with the
10369
** [SQLITE_OMIT_DESERIALIZE] option.
10370
*/
10371
SQLITE_API int sqlite3_deserialize(
10372
  sqlite3 *db,            /* The database connection */
10373
  const char *zSchema,    /* Which DB to reopen with the deserialization */
10374
  unsigned char *pData,   /* The serialized database content */
10375
  sqlite3_int64 szDb,     /* Number bytes in the deserialization */
10376
  sqlite3_int64 szBuf,    /* Total size of buffer pData[] */
10377
  unsigned mFlags         /* Zero or more SQLITE_DESERIALIZE_* flags */
10378
);
10379
10380
/*
10381
** CAPI3REF: Flags for sqlite3_deserialize()
10382
**
10383
** The following are allowed values for 6th argument (the F argument) to
10384
** the [sqlite3_deserialize(D,S,P,N,M,F)] interface.
10385
**
10386
** The SQLITE_DESERIALIZE_FREEONCLOSE means that the database serialization
10387
** in the P argument is held in memory obtained from [sqlite3_malloc64()]
10388
** and that SQLite should take ownership of this memory and automatically
10389
** free it when it has finished using it.  Without this flag, the caller
10390
** is responsible for freeing any dynamically allocated memory.
10391
**
10392
** The SQLITE_DESERIALIZE_RESIZEABLE flag means that SQLite is allowed to
10393
** grow the size of the database using calls to [sqlite3_realloc64()].  This
10394
** flag should only be used if SQLITE_DESERIALIZE_FREEONCLOSE is also used.
10395
** Without this flag, the deserialized database cannot increase in size beyond
10396
** the number of bytes specified by the M parameter.
10397
**
10398
** The SQLITE_DESERIALIZE_READONLY flag means that the deserialized database
10399
** should be treated as read-only.
10400
*/
10401
2
#define SQLITE_DESERIALIZE_FREEONCLOSE 1 /* Call sqlite3_free() on close */
10402
2
#define SQLITE_DESERIALIZE_RESIZEABLE  2 /* Resize using sqlite3_realloc64() */
10403
#define SQLITE_DESERIALIZE_READONLY    4 /* Database is read-only */
10404
10405
/*
10406
** Undo the hack that converts floating point types to integer for
10407
** builds on processors without floating point support.
10408
*/
10409
#ifdef SQLITE_OMIT_FLOATING_POINT
10410
# undef double
10411
#endif
10412
10413
#ifdef __cplusplus
10414
}  /* End of the 'extern "C"' block */
10415
#endif
10416
#endif /* SQLITE3_H */
10417
10418
/******** Begin file sqlite3rtree.h *********/
10419
/*
10420
** 2010 August 30
10421
**
10422
** The author disclaims copyright to this source code.  In place of
10423
** a legal notice, here is a blessing:
10424
**
10425
**    May you do good and not evil.
10426
**    May you find forgiveness for yourself and forgive others.
10427
**    May you share freely, never taking more than you give.
10428
**
10429
*************************************************************************
10430
*/
10431
10432
#ifndef _SQLITE3RTREE_H_
10433
#define _SQLITE3RTREE_H_
10434
10435
10436
#ifdef __cplusplus
10437
extern "C" {
10438
#endif
10439
10440
typedef struct sqlite3_rtree_geometry sqlite3_rtree_geometry;
10441
typedef struct sqlite3_rtree_query_info sqlite3_rtree_query_info;
10442
10443
/* The double-precision datatype used by RTree depends on the
10444
** SQLITE_RTREE_INT_ONLY compile-time option.
10445
*/
10446
#ifdef SQLITE_RTREE_INT_ONLY
10447
  typedef sqlite3_int64 sqlite3_rtree_dbl;
10448
#else
10449
  typedef double sqlite3_rtree_dbl;
10450
#endif
10451
10452
/*
10453
** Register a geometry callback named zGeom that can be used as part of an
10454
** R-Tree geometry query as follows:
10455
**
10456
**   SELECT ... FROM <rtree> WHERE <rtree col> MATCH $zGeom(... params ...)
10457
*/
10458
SQLITE_API int sqlite3_rtree_geometry_callback(
10459
  sqlite3 *db,
10460
  const char *zGeom,
10461
  int (*xGeom)(sqlite3_rtree_geometry*, int, sqlite3_rtree_dbl*,int*),
10462
  void *pContext
10463
);
10464
10465
10466
/*
10467
** A pointer to a structure of the following type is passed as the first
10468
** argument to callbacks registered using rtree_geometry_callback().
10469
*/
10470
struct sqlite3_rtree_geometry {
10471
  void *pContext;                 /* Copy of pContext passed to s_r_g_c() */
10472
  int nParam;                     /* Size of array aParam[] */
10473
  sqlite3_rtree_dbl *aParam;      /* Parameters passed to SQL geom function */
10474
  void *pUser;                    /* Callback implementation user data */
10475
  void (*xDelUser)(void *);       /* Called by SQLite to clean up pUser */
10476
};
10477
10478
/*
10479
** Register a 2nd-generation geometry callback named zScore that can be
10480
** used as part of an R-Tree geometry query as follows:
10481
**
10482
**   SELECT ... FROM <rtree> WHERE <rtree col> MATCH $zQueryFunc(... params ...)
10483
*/
10484
SQLITE_API int sqlite3_rtree_query_callback(
10485
  sqlite3 *db,
10486
  const char *zQueryFunc,
10487
  int (*xQueryFunc)(sqlite3_rtree_query_info*),
10488
  void *pContext,
10489
  void (*xDestructor)(void*)
10490
);
10491
10492
10493
/*
10494
** A pointer to a structure of the following type is passed as the
10495
** argument to scored geometry callback registered using
10496
** sqlite3_rtree_query_callback().
10497
**
10498
** Note that the first 5 fields of this structure are identical to
10499
** sqlite3_rtree_geometry.  This structure is a subclass of
10500
** sqlite3_rtree_geometry.
10501
*/
10502
struct sqlite3_rtree_query_info {
10503
  void *pContext;                   /* pContext from when function registered */
10504
  int nParam;                       /* Number of function parameters */
10505
  sqlite3_rtree_dbl *aParam;        /* value of function parameters */
10506
  void *pUser;                      /* callback can use this, if desired */
10507
  void (*xDelUser)(void*);          /* function to free pUser */
10508
  sqlite3_rtree_dbl *aCoord;        /* Coordinates of node or entry to check */
10509
  unsigned int *anQueue;            /* Number of pending entries in the queue */
10510
  int nCoord;                       /* Number of coordinates */
10511
  int iLevel;                       /* Level of current node or entry */
10512
  int mxLevel;                      /* The largest iLevel value in the tree */
10513
  sqlite3_int64 iRowid;             /* Rowid for current entry */
10514
  sqlite3_rtree_dbl rParentScore;   /* Score of parent node */
10515
  int eParentWithin;                /* Visibility of parent node */
10516
  int eWithin;                      /* OUT: Visibility */
10517
  sqlite3_rtree_dbl rScore;         /* OUT: Write the score here */
10518
  /* The following fields are only available in 3.8.11 and later */
10519
  sqlite3_value **apSqlParam;       /* Original SQL values of parameters */
10520
};
10521
10522
/*
10523
** Allowed values for sqlite3_rtree_query.eWithin and .eParentWithin.
10524
*/
10525
#define NOT_WITHIN       0   /* Object completely outside of query region */
10526
#define PARTLY_WITHIN    1   /* Object partially overlaps query region */
10527
#define FULLY_WITHIN     2   /* Object fully contained within query region */
10528
10529
10530
#ifdef __cplusplus
10531
}  /* end of the 'extern "C"' block */
10532
#endif
10533
10534
#endif  /* ifndef _SQLITE3RTREE_H_ */
10535
10536
/******** End of sqlite3rtree.h *********/
10537
/******** Begin file sqlite3session.h *********/
10538
10539
#if !defined(__SQLITESESSION_H_) && defined(SQLITE_ENABLE_SESSION)
10540
#define __SQLITESESSION_H_ 1
10541
10542
/*
10543
** Make sure we can call this stuff from C++.
10544
*/
10545
#ifdef __cplusplus
10546
extern "C" {
10547
#endif
10548
10549
10550
/*
10551
** CAPI3REF: Session Object Handle
10552
**
10553
** An instance of this object is a [session] that can be used to
10554
** record changes to a database.
10555
*/
10556
typedef struct sqlite3_session sqlite3_session;
10557
10558
/*
10559
** CAPI3REF: Changeset Iterator Handle
10560
**
10561
** An instance of this object acts as a cursor for iterating
10562
** over the elements of a [changeset] or [patchset].
10563
*/
10564
typedef struct sqlite3_changeset_iter sqlite3_changeset_iter;
10565
10566
/*
10567
** CAPI3REF: Create A New Session Object
10568
** CONSTRUCTOR: sqlite3_session
10569
**
10570
** Create a new session object attached to database handle db. If successful,
10571
** a pointer to the new object is written to *ppSession and SQLITE_OK is
10572
** returned. If an error occurs, *ppSession is set to NULL and an SQLite
10573
** error code (e.g. SQLITE_NOMEM) is returned.
10574
**
10575
** It is possible to create multiple session objects attached to a single
10576
** database handle.
10577
**
10578
** Session objects created using this function should be deleted using the
10579
** [sqlite3session_delete()] function before the database handle that they
10580
** are attached to is itself closed. If the database handle is closed before
10581
** the session object is deleted, then the results of calling any session
10582
** module function, including [sqlite3session_delete()] on the session object
10583
** are undefined.
10584
**
10585
** Because the session module uses the [sqlite3_preupdate_hook()] API, it
10586
** is not possible for an application to register a pre-update hook on a
10587
** database handle that has one or more session objects attached. Nor is
10588
** it possible to create a session object attached to a database handle for
10589
** which a pre-update hook is already defined. The results of attempting
10590
** either of these things are undefined.
10591
**
10592
** The session object will be used to create changesets for tables in
10593
** database zDb, where zDb is either "main", or "temp", or the name of an
10594
** attached database. It is not an error if database zDb is not attached
10595
** to the database when the session object is created.
10596
*/
10597
SQLITE_API int sqlite3session_create(
10598
  sqlite3 *db,                    /* Database handle */
10599
  const char *zDb,                /* Name of db (e.g. "main") */
10600
  sqlite3_session **ppSession     /* OUT: New session object */
10601
);
10602
10603
/*
10604
** CAPI3REF: Delete A Session Object
10605
** DESTRUCTOR: sqlite3_session
10606
**
10607
** Delete a session object previously allocated using
10608
** [sqlite3session_create()]. Once a session object has been deleted, the
10609
** results of attempting to use pSession with any other session module
10610
** function are undefined.
10611
**
10612
** Session objects must be deleted before the database handle to which they
10613
** are attached is closed. Refer to the documentation for
10614
** [sqlite3session_create()] for details.
10615
*/
10616
SQLITE_API void sqlite3session_delete(sqlite3_session *pSession);
10617
10618
/*
10619
** CAPIREF: Conigure a Session Object
10620
** METHOD: sqlite3_session
10621
**
10622
** This method is used to configure a session object after it has been
10623
** created. At present the only valid value for the second parameter is
10624
** [SQLITE_SESSION_OBJCONFIG_SIZE].
10625
**
10626
** Arguments for sqlite3session_object_config()
10627
**
10628
** The following values may passed as the the 4th parameter to
10629
** sqlite3session_object_config().
10630
**
10631
** <dt>SQLITE_SESSION_OBJCONFIG_SIZE <dd>
10632
**   This option is used to set, clear or query the flag that enables
10633
**   the [sqlite3session_changeset_size()] API. Because it imposes some
10634
**   computational overhead, this API is disabled by default. Argument
10635
**   pArg must point to a value of type (int). If the value is initially
10636
**   0, then the sqlite3session_changeset_size() API is disabled. If it
10637
**   is greater than 0, then the same API is enabled. Or, if the initial
10638
**   value is less than zero, no change is made. In all cases the (int)
10639
**   variable is set to 1 if the sqlite3session_changeset_size() API is
10640
**   enabled following the current call, or 0 otherwise.
10641
**
10642
**   It is an error (SQLITE_MISUSE) to attempt to modify this setting after
10643
**   the first table has been attached to the session object.
10644
*/
10645
SQLITE_API int sqlite3session_object_config(sqlite3_session*, int op, void *pArg);
10646
10647
/*
10648
*/
10649
#define SQLITE_SESSION_OBJCONFIG_SIZE 1
10650
10651
/*
10652
** CAPI3REF: Enable Or Disable A Session Object
10653
** METHOD: sqlite3_session
10654
**
10655
** Enable or disable the recording of changes by a session object. When
10656
** enabled, a session object records changes made to the database. When
10657
** disabled - it does not. A newly created session object is enabled.
10658
** Refer to the documentation for [sqlite3session_changeset()] for further
10659
** details regarding how enabling and disabling a session object affects
10660
** the eventual changesets.
10661
**
10662
** Passing zero to this function disables the session. Passing a value
10663
** greater than zero enables it. Passing a value less than zero is a
10664
** no-op, and may be used to query the current state of the session.
10665
**
10666
** The return value indicates the final state of the session object: 0 if
10667
** the session is disabled, or 1 if it is enabled.
10668
*/
10669
SQLITE_API int sqlite3session_enable(sqlite3_session *pSession, int bEnable);
10670
10671
/*
10672
** CAPI3REF: Set Or Clear the Indirect Change Flag
10673
** METHOD: sqlite3_session
10674
**
10675
** Each change recorded by a session object is marked as either direct or
10676
** indirect. A change is marked as indirect if either:
10677
**
10678
** <ul>
10679
**   <li> The session object "indirect" flag is set when the change is
10680
**        made, or
10681
**   <li> The change is made by an SQL trigger or foreign key action
10682
**        instead of directly as a result of a users SQL statement.
10683
** </ul>
10684
**
10685
** If a single row is affected by more than one operation within a session,
10686
** then the change is considered indirect if all operations meet the criteria
10687
** for an indirect change above, or direct otherwise.
10688
**
10689
** This function is used to set, clear or query the session object indirect
10690
** flag.  If the second argument passed to this function is zero, then the
10691
** indirect flag is cleared. If it is greater than zero, the indirect flag
10692
** is set. Passing a value less than zero does not modify the current value
10693
** of the indirect flag, and may be used to query the current state of the
10694
** indirect flag for the specified session object.
10695
**
10696
** The return value indicates the final state of the indirect flag: 0 if
10697
** it is clear, or 1 if it is set.
10698
*/
10699
SQLITE_API int sqlite3session_indirect(sqlite3_session *pSession, int bIndirect);
10700
10701
/*
10702
** CAPI3REF: Attach A Table To A Session Object
10703
** METHOD: sqlite3_session
10704
**
10705
** If argument zTab is not NULL, then it is the name of a table to attach
10706
** to the session object passed as the first argument. All subsequent changes
10707
** made to the table while the session object is enabled will be recorded. See
10708
** documentation for [sqlite3session_changeset()] for further details.
10709
**
10710
** Or, if argument zTab is NULL, then changes are recorded for all tables
10711
** in the database. If additional tables are added to the database (by
10712
** executing "CREATE TABLE" statements) after this call is made, changes for
10713
** the new tables are also recorded.
10714
**
10715
** Changes can only be recorded for tables that have a PRIMARY KEY explicitly
10716
** defined as part of their CREATE TABLE statement. It does not matter if the
10717
** PRIMARY KEY is an "INTEGER PRIMARY KEY" (rowid alias) or not. The PRIMARY
10718
** KEY may consist of a single column, or may be a composite key.
10719
**
10720
** It is not an error if the named table does not exist in the database. Nor
10721
** is it an error if the named table does not have a PRIMARY KEY. However,
10722
** no changes will be recorded in either of these scenarios.
10723
**
10724
** Changes are not recorded for individual rows that have NULL values stored
10725
** in one or more of their PRIMARY KEY columns.
10726
**
10727
** SQLITE_OK is returned if the call completes without error. Or, if an error
10728
** occurs, an SQLite error code (e.g. SQLITE_NOMEM) is returned.
10729
**
10730
** <h3>Special sqlite_stat1 Handling</h3>
10731
**
10732
** As of SQLite version 3.22.0, the "sqlite_stat1" table is an exception to
10733
** some of the rules above. In SQLite, the schema of sqlite_stat1 is:
10734
**  <pre>
10735
**  &nbsp;     CREATE TABLE sqlite_stat1(tbl,idx,stat)
10736
**  </pre>
10737
**
10738
** Even though sqlite_stat1 does not have a PRIMARY KEY, changes are
10739
** recorded for it as if the PRIMARY KEY is (tbl,idx). Additionally, changes
10740
** are recorded for rows for which (idx IS NULL) is true. However, for such
10741
** rows a zero-length blob (SQL value X'') is stored in the changeset or
10742
** patchset instead of a NULL value. This allows such changesets to be
10743
** manipulated by legacy implementations of sqlite3changeset_invert(),
10744
** concat() and similar.
10745
**
10746
** The sqlite3changeset_apply() function automatically converts the
10747
** zero-length blob back to a NULL value when updating the sqlite_stat1
10748
** table. However, if the application calls sqlite3changeset_new(),
10749
** sqlite3changeset_old() or sqlite3changeset_conflict on a changeset
10750
** iterator directly (including on a changeset iterator passed to a
10751
** conflict-handler callback) then the X'' value is returned. The application
10752
** must translate X'' to NULL itself if required.
10753
**
10754
** Legacy (older than 3.22.0) versions of the sessions module cannot capture
10755
** changes made to the sqlite_stat1 table. Legacy versions of the
10756
** sqlite3changeset_apply() function silently ignore any modifications to the
10757
** sqlite_stat1 table that are part of a changeset or patchset.
10758
*/
10759
SQLITE_API int sqlite3session_attach(
10760
  sqlite3_session *pSession,      /* Session object */
10761
  const char *zTab                /* Table name */
10762
);
10763
10764
/*
10765
** CAPI3REF: Set a table filter on a Session Object.
10766
** METHOD: sqlite3_session
10767
**
10768
** The second argument (xFilter) is the "filter callback". For changes to rows
10769
** in tables that are not attached to the Session object, the filter is called
10770
** to determine whether changes to the table's rows should be tracked or not.
10771
** If xFilter returns 0, changes are not tracked. Note that once a table is
10772
** attached, xFilter will not be called again.
10773
*/
10774
SQLITE_API void sqlite3session_table_filter(
10775
  sqlite3_session *pSession,      /* Session object */
10776
  int(*xFilter)(
10777
    void *pCtx,                   /* Copy of third arg to _filter_table() */
10778
    const char *zTab              /* Table name */
10779
  ),
10780
  void *pCtx                      /* First argument passed to xFilter */
10781
);
10782
10783
/*
10784
** CAPI3REF: Generate A Changeset From A Session Object
10785
** METHOD: sqlite3_session
10786
**
10787
** Obtain a changeset containing changes to the tables attached to the
10788
** session object passed as the first argument. If successful,
10789
** set *ppChangeset to point to a buffer containing the changeset
10790
** and *pnChangeset to the size of the changeset in bytes before returning
10791
** SQLITE_OK. If an error occurs, set both *ppChangeset and *pnChangeset to
10792
** zero and return an SQLite error code.
10793
**
10794
** A changeset consists of zero or more INSERT, UPDATE and/or DELETE changes,
10795
** each representing a change to a single row of an attached table. An INSERT
10796
** change contains the values of each field of a new database row. A DELETE
10797
** contains the original values of each field of a deleted database row. An
10798
** UPDATE change contains the original values of each field of an updated
10799
** database row along with the updated values for each updated non-primary-key
10800
** column. It is not possible for an UPDATE change to represent a change that
10801
** modifies the values of primary key columns. If such a change is made, it
10802
** is represented in a changeset as a DELETE followed by an INSERT.
10803
**
10804
** Changes are not recorded for rows that have NULL values stored in one or
10805
** more of their PRIMARY KEY columns. If such a row is inserted or deleted,
10806
** no corresponding change is present in the changesets returned by this
10807
** function. If an existing row with one or more NULL values stored in
10808
** PRIMARY KEY columns is updated so that all PRIMARY KEY columns are non-NULL,
10809
** only an INSERT is appears in the changeset. Similarly, if an existing row
10810
** with non-NULL PRIMARY KEY values is updated so that one or more of its
10811
** PRIMARY KEY columns are set to NULL, the resulting changeset contains a
10812
** DELETE change only.
10813
**
10814
** The contents of a changeset may be traversed using an iterator created
10815
** using the [sqlite3changeset_start()] API. A changeset may be applied to
10816
** a database with a compatible schema using the [sqlite3changeset_apply()]
10817
** API.
10818
**
10819
** Within a changeset generated by this function, all changes related to a
10820
** single table are grouped together. In other words, when iterating through
10821
** a changeset or when applying a changeset to a database, all changes related
10822
** to a single table are processed before moving on to the next table. Tables
10823
** are sorted in the same order in which they were attached (or auto-attached)
10824
** to the sqlite3_session object. The order in which the changes related to
10825
** a single table are stored is undefined.
10826
**
10827
** Following a successful call to this function, it is the responsibility of
10828
** the caller to eventually free the buffer that *ppChangeset points to using
10829
** [sqlite3_free()].
10830
**
10831
** <h3>Changeset Generation</h3>
10832
**
10833
** Once a table has been attached to a session object, the session object
10834
** records the primary key values of all new rows inserted into the table.
10835
** It also records the original primary key and other column values of any
10836
** deleted or updated rows. For each unique primary key value, data is only
10837
** recorded once - the first time a row with said primary key is inserted,
10838
** updated or deleted in the lifetime of the session.
10839
**
10840
** There is one exception to the previous paragraph: when a row is inserted,
10841
** updated or deleted, if one or more of its primary key columns contain a
10842
** NULL value, no record of the change is made.
10843
**
10844
** The session object therefore accumulates two types of records - those
10845
** that consist of primary key values only (created when the user inserts
10846
** a new record) and those that consist of the primary key values and the
10847
** original values of other table columns (created when the users deletes
10848
** or updates a record).
10849
**
10850
** When this function is called, the requested changeset is created using
10851
** both the accumulated records and the current contents of the database
10852
** file. Specifically:
10853
**
10854
** <ul>
10855
**   <li> For each record generated by an insert, the database is queried
10856
**        for a row with a matching primary key. If one is found, an INSERT
10857
**        change is added to the changeset. If no such row is found, no change
10858
**        is added to the changeset.
10859
**
10860
**   <li> For each record generated by an update or delete, the database is
10861
**        queried for a row with a matching primary key. If such a row is
10862
**        found and one or more of the non-primary key fields have been
10863
**        modified from their original values, an UPDATE change is added to
10864
**        the changeset. Or, if no such row is found in the table, a DELETE
10865
**        change is added to the changeset. If there is a row with a matching
10866
**        primary key in the database, but all fields contain their original
10867
**        values, no change is added to the changeset.
10868
** </ul>
10869
**
10870
** This means, amongst other things, that if a row is inserted and then later
10871
** deleted while a session object is active, neither the insert nor the delete
10872
** will be present in the changeset. Or if a row is deleted and then later a
10873
** row with the same primary key values inserted while a session object is
10874
** active, the resulting changeset will contain an UPDATE change instead of
10875
** a DELETE and an INSERT.
10876
**
10877
** When a session object is disabled (see the [sqlite3session_enable()] API),
10878
** it does not accumulate records when rows are inserted, updated or deleted.
10879
** This may appear to have some counter-intuitive effects if a single row
10880
** is written to more than once during a session. For example, if a row
10881
** is inserted while a session object is enabled, then later deleted while
10882
** the same session object is disabled, no INSERT record will appear in the
10883
** changeset, even though the delete took place while the session was disabled.
10884
** Or, if one field of a row is updated while a session is disabled, and
10885
** another field of the same row is updated while the session is enabled, the
10886
** resulting changeset will contain an UPDATE change that updates both fields.
10887
*/
10888
SQLITE_API int sqlite3session_changeset(
10889
  sqlite3_session *pSession,      /* Session object */
10890
  int *pnChangeset,               /* OUT: Size of buffer at *ppChangeset */
10891
  void **ppChangeset              /* OUT: Buffer containing changeset */
10892
);
10893
10894
/*
10895
** CAPI3REF: Return An Upper-limit For The Size Of The Changeset
10896
** METHOD: sqlite3_session
10897
**
10898
** By default, this function always returns 0. For it to return
10899
** a useful result, the sqlite3_session object must have been configured
10900
** to enable this API using sqlite3session_object_config() with the
10901
** SQLITE_SESSION_OBJCONFIG_SIZE verb.
10902
**
10903
** When enabled, this function returns an upper limit, in bytes, for the size
10904
** of the changeset that might be produced if sqlite3session_changeset() were
10905
** called. The final changeset size might be equal to or smaller than the
10906
** size in bytes returned by this function.
10907
*/
10908
SQLITE_API sqlite3_int64 sqlite3session_changeset_size(sqlite3_session *pSession);
10909
10910
/*
10911
** CAPI3REF: Load The Difference Between Tables Into A Session
10912
** METHOD: sqlite3_session
10913
**
10914
** If it is not already attached to the session object passed as the first
10915
** argument, this function attaches table zTbl in the same manner as the
10916
** [sqlite3session_attach()] function. If zTbl does not exist, or if it
10917
** does not have a primary key, this function is a no-op (but does not return
10918
** an error).
10919
**
10920
** Argument zFromDb must be the name of a database ("main", "temp" etc.)
10921
** attached to the same database handle as the session object that contains
10922
** a table compatible with the table attached to the session by this function.
10923
** A table is considered compatible if it:
10924
**
10925
** <ul>
10926
**   <li> Has the same name,
10927
**   <li> Has the same set of columns declared in the same order, and
10928
**   <li> Has the same PRIMARY KEY definition.
10929
** </ul>
10930
**
10931
** If the tables are not compatible, SQLITE_SCHEMA is returned. If the tables
10932
** are compatible but do not have any PRIMARY KEY columns, it is not an error
10933
** but no changes are added to the session object. As with other session
10934
** APIs, tables without PRIMARY KEYs are simply ignored.
10935
**
10936
** This function adds a set of changes to the session object that could be
10937
** used to update the table in database zFrom (call this the "from-table")
10938
** so that its content is the same as the table attached to the session
10939
** object (call this the "to-table"). Specifically:
10940
**
10941
** <ul>
10942
**   <li> For each row (primary key) that exists in the to-table but not in
10943
**     the from-table, an INSERT record is added to the session object.
10944
**
10945
**   <li> For each row (primary key) that exists in the to-table but not in
10946
**     the from-table, a DELETE record is added to the session object.
10947
**
10948
**   <li> For each row (primary key) that exists in both tables, but features
10949
**     different non-PK values in each, an UPDATE record is added to the
10950
**     session.
10951
** </ul>
10952
**
10953
** To clarify, if this function is called and then a changeset constructed
10954
** using [sqlite3session_changeset()], then after applying that changeset to
10955
** database zFrom the contents of the two compatible tables would be
10956
** identical.
10957
**
10958
** It an error if database zFrom does not exist or does not contain the
10959
** required compatible table.
10960
**
10961
** If the operation is successful, SQLITE_OK is returned. Otherwise, an SQLite
10962
** error code. In this case, if argument pzErrMsg is not NULL, *pzErrMsg
10963
** may be set to point to a buffer containing an English language error
10964
** message. It is the responsibility of the caller to free this buffer using
10965
** sqlite3_free().
10966
*/
10967
SQLITE_API int sqlite3session_diff(
10968
  sqlite3_session *pSession,
10969
  const char *zFromDb,
10970
  const char *zTbl,
10971
  char **pzErrMsg
10972
);
10973
10974
10975
/*
10976
** CAPI3REF: Generate A Patchset From A Session Object
10977
** METHOD: sqlite3_session
10978
**
10979
** The differences between a patchset and a changeset are that:
10980
**
10981
** <ul>
10982
**   <li> DELETE records consist of the primary key fields only. The
10983
**        original values of other fields are omitted.
10984
**   <li> The original values of any modified fields are omitted from
10985
**        UPDATE records.
10986
** </ul>
10987
**
10988
** A patchset blob may be used with up to date versions of all
10989
** sqlite3changeset_xxx API functions except for sqlite3changeset_invert(),
10990
** which returns SQLITE_CORRUPT if it is passed a patchset. Similarly,
10991
** attempting to use a patchset blob with old versions of the
10992
** sqlite3changeset_xxx APIs also provokes an SQLITE_CORRUPT error.
10993
**
10994
** Because the non-primary key "old.*" fields are omitted, no
10995
** SQLITE_CHANGESET_DATA conflicts can be detected or reported if a patchset
10996
** is passed to the sqlite3changeset_apply() API. Other conflict types work
10997
** in the same way as for changesets.
10998
**
10999
** Changes within a patchset are ordered in the same way as for changesets
11000
** generated by the sqlite3session_changeset() function (i.e. all changes for
11001
** a single table are grouped together, tables appear in the order in which
11002
** they were attached to the session object).
11003
*/
11004
SQLITE_API int sqlite3session_patchset(
11005
  sqlite3_session *pSession,      /* Session object */
11006
  int *pnPatchset,                /* OUT: Size of buffer at *ppPatchset */
11007
  void **ppPatchset               /* OUT: Buffer containing patchset */
11008
);
11009
11010
/*
11011
** CAPI3REF: Test if a changeset has recorded any changes.
11012
**
11013
** Return non-zero if no changes to attached tables have been recorded by
11014
** the session object passed as the first argument. Otherwise, if one or
11015
** more changes have been recorded, return zero.
11016
**
11017
** Even if this function returns zero, it is possible that calling
11018
** [sqlite3session_changeset()] on the session handle may still return a
11019
** changeset that contains no changes. This can happen when a row in
11020
** an attached table is modified and then later on the original values
11021
** are restored. However, if this function returns non-zero, then it is
11022
** guaranteed that a call to sqlite3session_changeset() will return a
11023
** changeset containing zero changes.
11024
*/
11025
SQLITE_API int sqlite3session_isempty(sqlite3_session *pSession);
11026
11027
/*
11028
** CAPI3REF: Query for the amount of heap memory used by a session object.
11029
**
11030
** This API returns the total amount of heap memory in bytes currently
11031
** used by the session object passed as the only argument.
11032
*/
11033
SQLITE_API sqlite3_int64 sqlite3session_memory_used(sqlite3_session *pSession);
11034
11035
/*
11036
** CAPI3REF: Create An Iterator To Traverse A Changeset
11037
** CONSTRUCTOR: sqlite3_changeset_iter
11038
**
11039
** Create an iterator used to iterate through the contents of a changeset.
11040
** If successful, *pp is set to point to the iterator handle and SQLITE_OK
11041
** is returned. Otherwise, if an error occurs, *pp is set to zero and an
11042
** SQLite error code is returned.
11043
**
11044
** The following functions can be used to advance and query a changeset
11045
** iterator created by this function:
11046
**
11047
** <ul>
11048
**   <li> [sqlite3changeset_next()]
11049
**   <li> [sqlite3changeset_op()]
11050
**   <li> [sqlite3changeset_new()]
11051
**   <li> [sqlite3changeset_old()]
11052
** </ul>
11053
**
11054
** It is the responsibility of the caller to eventually destroy the iterator
11055
** by passing it to [sqlite3changeset_finalize()]. The buffer containing the
11056
** changeset (pChangeset) must remain valid until after the iterator is
11057
** destroyed.
11058
**
11059
** Assuming the changeset blob was created by one of the
11060
** [sqlite3session_changeset()], [sqlite3changeset_concat()] or
11061
** [sqlite3changeset_invert()] functions, all changes within the changeset
11062
** that apply to a single table are grouped together. This means that when
11063
** an application iterates through a changeset using an iterator created by
11064
** this function, all changes that relate to a single table are visited
11065
** consecutively. There is no chance that the iterator will visit a change
11066
** the applies to table X, then one for table Y, and then later on visit
11067
** another change for table X.
11068
**
11069
** The behavior of sqlite3changeset_start_v2() and its streaming equivalent
11070
** may be modified by passing a combination of
11071
** [SQLITE_CHANGESETSTART_INVERT | supported flags] as the 4th parameter.
11072
**
11073
** Note that the sqlite3changeset_start_v2() API is still <b>experimental</b>
11074
** and therefore subject to change.
11075
*/
11076
SQLITE_API int sqlite3changeset_start(
11077
  sqlite3_changeset_iter **pp,    /* OUT: New changeset iterator handle */
11078
  int nChangeset,                 /* Size of changeset blob in bytes */
11079
  void *pChangeset                /* Pointer to blob containing changeset */
11080
);
11081
SQLITE_API int sqlite3changeset_start_v2(
11082
  sqlite3_changeset_iter **pp,    /* OUT: New changeset iterator handle */
11083
  int nChangeset,                 /* Size of changeset blob in bytes */
11084
  void *pChangeset,               /* Pointer to blob containing changeset */
11085
  int flags                       /* SESSION_CHANGESETSTART_* flags */
11086
);
11087
11088
/*
11089
** CAPI3REF: Flags for sqlite3changeset_start_v2
11090
**
11091
** The following flags may passed via the 4th parameter to
11092
** [sqlite3changeset_start_v2] and [sqlite3changeset_start_v2_strm]:
11093
**
11094
** <dt>SQLITE_CHANGESETAPPLY_INVERT <dd>
11095
**   Invert the changeset while iterating through it. This is equivalent to
11096
**   inverting a changeset using sqlite3changeset_invert() before applying it.
11097
**   It is an error to specify this flag with a patchset.
11098
*/
11099
#define SQLITE_CHANGESETSTART_INVERT        0x0002
11100
11101
11102
/*
11103
** CAPI3REF: Advance A Changeset Iterator
11104
** METHOD: sqlite3_changeset_iter
11105
**
11106
** This function may only be used with iterators created by the function
11107
** [sqlite3changeset_start()]. If it is called on an iterator passed to
11108
** a conflict-handler callback by [sqlite3changeset_apply()], SQLITE_MISUSE
11109
** is returned and the call has no effect.
11110
**
11111
** Immediately after an iterator is created by sqlite3changeset_start(), it
11112
** does not point to any change in the changeset. Assuming the changeset
11113
** is not empty, the first call to this function advances the iterator to
11114
** point to the first change in the changeset. Each subsequent call advances
11115
** the iterator to point to the next change in the changeset (if any). If
11116
** no error occurs and the iterator points to a valid change after a call
11117
** to sqlite3changeset_next() has advanced it, SQLITE_ROW is returned.
11118
** Otherwise, if all changes in the changeset have already been visited,
11119
** SQLITE_DONE is returned.
11120
**
11121
** If an error occurs, an SQLite error code is returned. Possible error
11122
** codes include SQLITE_CORRUPT (if the changeset buffer is corrupt) or
11123
** SQLITE_NOMEM.
11124
*/
11125
SQLITE_API int sqlite3changeset_next(sqlite3_changeset_iter *pIter);
11126
11127
/*
11128
** CAPI3REF: Obtain The Current Operation From A Changeset Iterator
11129
** METHOD: sqlite3_changeset_iter
11130
**
11131
** The pIter argument passed to this function may either be an iterator
11132
** passed to a conflict-handler by [sqlite3changeset_apply()], or an iterator
11133
** created by [sqlite3changeset_start()]. In the latter case, the most recent
11134
** call to [sqlite3changeset_next()] must have returned [SQLITE_ROW]. If this
11135
** is not the case, this function returns [SQLITE_MISUSE].
11136
**
11137
** Arguments pOp, pnCol and pzTab may not be NULL. Upon return, three
11138
** outputs are set through these pointers:
11139
**
11140
** *pOp is set to one of [SQLITE_INSERT], [SQLITE_DELETE] or [SQLITE_UPDATE],
11141
** depending on the type of change that the iterator currently points to;
11142
**
11143
** *pnCol is set to the number of columns in the table affected by the change; and
11144
**
11145
** *pzTab is set to point to a nul-terminated utf-8 encoded string containing
11146
** the name of the table affected by the current change. The buffer remains
11147
** valid until either sqlite3changeset_next() is called on the iterator
11148
** or until the conflict-handler function returns.
11149
**
11150
** If pbIndirect is not NULL, then *pbIndirect is set to true (1) if the change
11151
** is an indirect change, or false (0) otherwise. See the documentation for
11152
** [sqlite3session_indirect()] for a description of direct and indirect
11153
** changes.
11154
**
11155
** If no error occurs, SQLITE_OK is returned. If an error does occur, an
11156
** SQLite error code is returned. The values of the output variables may not
11157
** be trusted in this case.
11158
*/
11159
SQLITE_API int sqlite3changeset_op(
11160
  sqlite3_changeset_iter *pIter,  /* Iterator object */
11161
  const char **pzTab,             /* OUT: Pointer to table name */
11162
  int *pnCol,                     /* OUT: Number of columns in table */
11163
  int *pOp,                       /* OUT: SQLITE_INSERT, DELETE or UPDATE */
11164
  int *pbIndirect                 /* OUT: True for an 'indirect' change */
11165
);
11166
11167
/*
11168
** CAPI3REF: Obtain The Primary Key Definition Of A Table
11169
** METHOD: sqlite3_changeset_iter
11170
**
11171
** For each modified table, a changeset includes the following:
11172
**
11173
** <ul>
11174
**   <li> The number of columns in the table, and
11175
**   <li> Which of those columns make up the tables PRIMARY KEY.
11176
** </ul>
11177
**
11178
** This function is used to find which columns comprise the PRIMARY KEY of
11179
** the table modified by the change that iterator pIter currently points to.
11180
** If successful, *pabPK is set to point to an array of nCol entries, where
11181
** nCol is the number of columns in the table. Elements of *pabPK are set to
11182
** 0x01 if the corresponding column is part of the tables primary key, or
11183
** 0x00 if it is not.
11184
**
11185
** If argument pnCol is not NULL, then *pnCol is set to the number of columns
11186
** in the table.
11187
**
11188
** If this function is called when the iterator does not point to a valid
11189
** entry, SQLITE_MISUSE is returned and the output variables zeroed. Otherwise,
11190
** SQLITE_OK is returned and the output variables populated as described
11191
** above.
11192
*/
11193
SQLITE_API int sqlite3changeset_pk(
11194
  sqlite3_changeset_iter *pIter,  /* Iterator object */
11195
  unsigned char **pabPK,          /* OUT: Array of boolean - true for PK cols */
11196
  int *pnCol                      /* OUT: Number of entries in output array */
11197
);
11198
11199
/*
11200
** CAPI3REF: Obtain old.* Values From A Changeset Iterator
11201
** METHOD: sqlite3_changeset_iter
11202
**
11203
** The pIter argument passed to this function may either be an iterator
11204
** passed to a conflict-handler by [sqlite3changeset_apply()], or an iterator
11205
** created by [sqlite3changeset_start()]. In the latter case, the most recent
11206
** call to [sqlite3changeset_next()] must have returned SQLITE_ROW.
11207
** Furthermore, it may only be called if the type of change that the iterator
11208
** currently points to is either [SQLITE_DELETE] or [SQLITE_UPDATE]. Otherwise,
11209
** this function returns [SQLITE_MISUSE] and sets *ppValue to NULL.
11210
**
11211
** Argument iVal must be greater than or equal to 0, and less than the number
11212
** of columns in the table affected by the current change. Otherwise,
11213
** [SQLITE_RANGE] is returned and *ppValue is set to NULL.
11214
**
11215
** If successful, this function sets *ppValue to point to a protected
11216
** sqlite3_value object containing the iVal'th value from the vector of
11217
** original row values stored as part of the UPDATE or DELETE change and
11218
** returns SQLITE_OK. The name of the function comes from the fact that this
11219
** is similar to the "old.*" columns available to update or delete triggers.
11220
**
11221
** If some other error occurs (e.g. an OOM condition), an SQLite error code
11222
** is returned and *ppValue is set to NULL.
11223
*/
11224
SQLITE_API int sqlite3changeset_old(
11225
  sqlite3_changeset_iter *pIter,  /* Changeset iterator */
11226
  int iVal,                       /* Column number */
11227
  sqlite3_value **ppValue         /* OUT: Old value (or NULL pointer) */
11228
);
11229
11230
/*
11231
** CAPI3REF: Obtain new.* Values From A Changeset Iterator
11232
** METHOD: sqlite3_changeset_iter
11233
**
11234
** The pIter argument passed to this function may either be an iterator
11235
** passed to a conflict-handler by [sqlite3changeset_apply()], or an iterator
11236
** created by [sqlite3changeset_start()]. In the latter case, the most recent
11237
** call to [sqlite3changeset_next()] must have returned SQLITE_ROW.
11238
** Furthermore, it may only be called if the type of change that the iterator
11239
** currently points to is either [SQLITE_UPDATE] or [SQLITE_INSERT]. Otherwise,
11240
** this function returns [SQLITE_MISUSE] and sets *ppValue to NULL.
11241
**
11242
** Argument iVal must be greater than or equal to 0, and less than the number
11243
** of columns in the table affected by the current change. Otherwise,
11244
** [SQLITE_RANGE] is returned and *ppValue is set to NULL.
11245
**
11246
** If successful, this function sets *ppValue to point to a protected
11247
** sqlite3_value object containing the iVal'th value from the vector of
11248
** new row values stored as part of the UPDATE or INSERT change and
11249
** returns SQLITE_OK. If the change is an UPDATE and does not include
11250
** a new value for the requested column, *ppValue is set to NULL and
11251
** SQLITE_OK returned. The name of the function comes from the fact that
11252
** this is similar to the "new.*" columns available to update or delete
11253
** triggers.
11254
**
11255
** If some other error occurs (e.g. an OOM condition), an SQLite error code
11256
** is returned and *ppValue is set to NULL.
11257
*/
11258
SQLITE_API int sqlite3changeset_new(
11259
  sqlite3_changeset_iter *pIter,  /* Changeset iterator */
11260
  int iVal,                       /* Column number */
11261
  sqlite3_value **ppValue         /* OUT: New value (or NULL pointer) */
11262
);
11263
11264
/*
11265
** CAPI3REF: Obtain Conflicting Row Values From A Changeset Iterator
11266
** METHOD: sqlite3_changeset_iter
11267
**
11268
** This function should only be used with iterator objects passed to a
11269
** conflict-handler callback by [sqlite3changeset_apply()] with either
11270
** [SQLITE_CHANGESET_DATA] or [SQLITE_CHANGESET_CONFLICT]. If this function
11271
** is called on any other iterator, [SQLITE_MISUSE] is returned and *ppValue
11272
** is set to NULL.
11273
**
11274
** Argument iVal must be greater than or equal to 0, and less than the number
11275
** of columns in the table affected by the current change. Otherwise,
11276
** [SQLITE_RANGE] is returned and *ppValue is set to NULL.
11277
**
11278
** If successful, this function sets *ppValue to point to a protected
11279
** sqlite3_value object containing the iVal'th value from the
11280
** "conflicting row" associated with the current conflict-handler callback
11281
** and returns SQLITE_OK.
11282
**
11283
** If some other error occurs (e.g. an OOM condition), an SQLite error code
11284
** is returned and *ppValue is set to NULL.
11285
*/
11286
SQLITE_API int sqlite3changeset_conflict(
11287
  sqlite3_changeset_iter *pIter,  /* Changeset iterator */
11288
  int iVal,                       /* Column number */
11289
  sqlite3_value **ppValue         /* OUT: Value from conflicting row */
11290
);
11291
11292
/*
11293
** CAPI3REF: Determine The Number Of Foreign Key Constraint Violations
11294
** METHOD: sqlite3_changeset_iter
11295
**
11296
** This function may only be called with an iterator passed to an
11297
** SQLITE_CHANGESET_FOREIGN_KEY conflict handler callback. In this case
11298
** it sets the output variable to the total number of known foreign key
11299
** violations in the destination database and returns SQLITE_OK.
11300
**
11301
** In all other cases this function returns SQLITE_MISUSE.
11302
*/
11303
SQLITE_API int sqlite3changeset_fk_conflicts(
11304
  sqlite3_changeset_iter *pIter,  /* Changeset iterator */
11305
  int *pnOut                      /* OUT: Number of FK violations */
11306
);
11307
11308
11309
/*
11310
** CAPI3REF: Finalize A Changeset Iterator
11311
** METHOD: sqlite3_changeset_iter
11312
**
11313
** This function is used to finalize an iterator allocated with
11314
** [sqlite3changeset_start()].
11315
**
11316
** This function should only be called on iterators created using the
11317
** [sqlite3changeset_start()] function. If an application calls this
11318
** function with an iterator passed to a conflict-handler by
11319
** [sqlite3changeset_apply()], [SQLITE_MISUSE] is immediately returned and the
11320
** call has no effect.
11321
**
11322
** If an error was encountered within a call to an sqlite3changeset_xxx()
11323
** function (for example an [SQLITE_CORRUPT] in [sqlite3changeset_next()] or an
11324
** [SQLITE_NOMEM] in [sqlite3changeset_new()]) then an error code corresponding
11325
** to that error is returned by this function. Otherwise, SQLITE_OK is
11326
** returned. This is to allow the following pattern (pseudo-code):
11327
**
11328
** <pre>
11329
**   sqlite3changeset_start();
11330
**   while( SQLITE_ROW==sqlite3changeset_next() ){
11331
**     // Do something with change.
11332
**   }
11333
**   rc = sqlite3changeset_finalize();
11334
**   if( rc!=SQLITE_OK ){
11335
**     // An error has occurred
11336
**   }
11337
** </pre>
11338
*/
11339
SQLITE_API int sqlite3changeset_finalize(sqlite3_changeset_iter *pIter);
11340
11341
/*
11342
** CAPI3REF: Invert A Changeset
11343
**
11344
** This function is used to "invert" a changeset object. Applying an inverted
11345
** changeset to a database reverses the effects of applying the uninverted
11346
** changeset. Specifically:
11347
**
11348
** <ul>
11349
**   <li> Each DELETE change is changed to an INSERT, and
11350
**   <li> Each INSERT change is changed to a DELETE, and
11351
**   <li> For each UPDATE change, the old.* and new.* values are exchanged.
11352
** </ul>
11353
**
11354
** This function does not change the order in which changes appear within
11355
** the changeset. It merely reverses the sense of each individual change.
11356
**
11357
** If successful, a pointer to a buffer containing the inverted changeset
11358
** is stored in *ppOut, the size of the same buffer is stored in *pnOut, and
11359
** SQLITE_OK is returned. If an error occurs, both *pnOut and *ppOut are
11360
** zeroed and an SQLite error code returned.
11361
**
11362
** It is the responsibility of the caller to eventually call sqlite3_free()
11363
** on the *ppOut pointer to free the buffer allocation following a successful
11364
** call to this function.
11365
**
11366
** WARNING/TODO: This function currently assumes that the input is a valid
11367
** changeset. If it is not, the results are undefined.
11368
*/
11369
SQLITE_API int sqlite3changeset_invert(
11370
  int nIn, const void *pIn,       /* Input changeset */
11371
  int *pnOut, void **ppOut        /* OUT: Inverse of input */
11372
);
11373
11374
/*
11375
** CAPI3REF: Concatenate Two Changeset Objects
11376
**
11377
** This function is used to concatenate two changesets, A and B, into a
11378
** single changeset. The result is a changeset equivalent to applying
11379
** changeset A followed by changeset B.
11380
**
11381
** This function combines the two input changesets using an
11382
** sqlite3_changegroup object. Calling it produces similar results as the
11383
** following code fragment:
11384
**
11385
** <pre>
11386
**   sqlite3_changegroup *pGrp;
11387
**   rc = sqlite3_changegroup_new(&pGrp);
11388
**   if( rc==SQLITE_OK ) rc = sqlite3changegroup_add(pGrp, nA, pA);
11389
**   if( rc==SQLITE_OK ) rc = sqlite3changegroup_add(pGrp, nB, pB);
11390
**   if( rc==SQLITE_OK ){
11391
**     rc = sqlite3changegroup_output(pGrp, pnOut, ppOut);
11392
**   }else{
11393
**     *ppOut = 0;
11394
**     *pnOut = 0;
11395
**   }
11396
** </pre>
11397
**
11398
** Refer to the sqlite3_changegroup documentation below for details.
11399
*/
11400
SQLITE_API int sqlite3changeset_concat(
11401
  int nA,                         /* Number of bytes in buffer pA */
11402
  void *pA,                       /* Pointer to buffer containing changeset A */
11403
  int nB,                         /* Number of bytes in buffer pB */
11404
  void *pB,                       /* Pointer to buffer containing changeset B */
11405
  int *pnOut,                     /* OUT: Number of bytes in output changeset */
11406
  void **ppOut                    /* OUT: Buffer containing output changeset */
11407
);
11408
11409
11410
/*
11411
** CAPI3REF: Changegroup Handle
11412
**
11413
** A changegroup is an object used to combine two or more
11414
** [changesets] or [patchsets]
11415
*/
11416
typedef struct sqlite3_changegroup sqlite3_changegroup;
11417
11418
/*
11419
** CAPI3REF: Create A New Changegroup Object
11420
** CONSTRUCTOR: sqlite3_changegroup
11421
**
11422
** An sqlite3_changegroup object is used to combine two or more changesets
11423
** (or patchsets) into a single changeset (or patchset). A single changegroup
11424
** object may combine changesets or patchsets, but not both. The output is
11425
** always in the same format as the input.
11426
**
11427
** If successful, this function returns SQLITE_OK and populates (*pp) with
11428
** a pointer to a new sqlite3_changegroup object before returning. The caller
11429
** should eventually free the returned object using a call to
11430
** sqlite3changegroup_delete(). If an error occurs, an SQLite error code
11431
** (i.e. SQLITE_NOMEM) is returned and *pp is set to NULL.
11432
**
11433
** The usual usage pattern for an sqlite3_changegroup object is as follows:
11434
**
11435
** <ul>
11436
**   <li> It is created using a call to sqlite3changegroup_new().
11437
**
11438
**   <li> Zero or more changesets (or patchsets) are added to the object
11439
**        by calling sqlite3changegroup_add().
11440
**
11441
**   <li> The result of combining all input changesets together is obtained
11442
**        by the application via a call to sqlite3changegroup_output().
11443
**
11444
**   <li> The object is deleted using a call to sqlite3changegroup_delete().
11445
** </ul>
11446
**
11447
** Any number of calls to add() and output() may be made between the calls to
11448
** new() and delete(), and in any order.
11449
**
11450
** As well as the regular sqlite3changegroup_add() and
11451
** sqlite3changegroup_output() functions, also available are the streaming
11452
** versions sqlite3changegroup_add_strm() and sqlite3changegroup_output_strm().
11453
*/
11454
SQLITE_API int sqlite3changegroup_new(sqlite3_changegroup **pp);
11455
11456
/*
11457
** CAPI3REF: Add A Changeset To A Changegroup
11458
** METHOD: sqlite3_changegroup
11459
**
11460
** Add all changes within the changeset (or patchset) in buffer pData (size
11461
** nData bytes) to the changegroup.
11462
**
11463
** If the buffer contains a patchset, then all prior calls to this function
11464
** on the same changegroup object must also have specified patchsets. Or, if
11465
** the buffer contains a changeset, so must have the earlier calls to this
11466
** function. Otherwise, SQLITE_ERROR is returned and no changes are added
11467
** to the changegroup.
11468
**
11469
** Rows within the changeset and changegroup are identified by the values in
11470
** their PRIMARY KEY columns. A change in the changeset is considered to
11471
** apply to the same row as a change already present in the changegroup if
11472
** the two rows have the same primary key.
11473
**
11474
** Changes to rows that do not already appear in the changegroup are
11475
** simply copied into it. Or, if both the new changeset and the changegroup
11476
** contain changes that apply to a single row, the final contents of the
11477
** changegroup depends on the type of each change, as follows:
11478
**
11479
** <table border=1 style="margin-left:8ex;margin-right:8ex">
11480
**   <tr><th style="white-space:pre">Existing Change  </th>
11481
**       <th style="white-space:pre">New Change       </th>
11482
**       <th>Output Change
11483
**   <tr><td>INSERT <td>INSERT <td>
11484
**       The new change is ignored. This case does not occur if the new
11485
**       changeset was recorded immediately after the changesets already
11486
**       added to the changegroup.
11487
**   <tr><td>INSERT <td>UPDATE <td>
11488
**       The INSERT change remains in the changegroup. The values in the
11489
**       INSERT change are modified as if the row was inserted by the
11490
**       existing change and then updated according to the new change.
11491
**   <tr><td>INSERT <td>DELETE <td>
11492
**       The existing INSERT is removed from the changegroup. The DELETE is
11493
**       not added.
11494
**   <tr><td>UPDATE <td>INSERT <td>
11495
**       The new change is ignored. This case does not occur if the new
11496
**       changeset was recorded immediately after the changesets already
11497
**       added to the changegroup.
11498
**   <tr><td>UPDATE <td>UPDATE <td>
11499
**       The existing UPDATE remains within the changegroup. It is amended
11500
**       so that the accompanying values are as if the row was updated once
11501
**       by the existing change and then again by the new change.
11502
**   <tr><td>UPDATE <td>DELETE <td>
11503
**       The existing UPDATE is replaced by the new DELETE within the
11504
**       changegroup.
11505
**   <tr><td>DELETE <td>INSERT <td>
11506
**       If one or more of the column values in the row inserted by the
11507
**       new change differ from those in the row deleted by the existing
11508
**       change, the existing DELETE is replaced by an UPDATE within the
11509
**       changegroup. Otherwise, if the inserted row is exactly the same
11510
**       as the deleted row, the existing DELETE is simply discarded.
11511
**   <tr><td>DELETE <td>UPDATE <td>
11512
**       The new change is ignored. This case does not occur if the new
11513
**       changeset was recorded immediately after the changesets already
11514
**       added to the changegroup.
11515
**   <tr><td>DELETE <td>DELETE <td>
11516
**       The new change is ignored. This case does not occur if the new
11517
**       changeset was recorded immediately after the changesets already
11518
**       added to the changegroup.
11519
** </table>
11520
**
11521
** If the new changeset contains changes to a table that is already present
11522
** in the changegroup, then the number of columns and the position of the
11523
** primary key columns for the table must be consistent. If this is not the
11524
** case, this function fails with SQLITE_SCHEMA. If the input changeset
11525
** appears to be corrupt and the corruption is detected, SQLITE_CORRUPT is
11526
** returned. Or, if an out-of-memory condition occurs during processing, this
11527
** function returns SQLITE_NOMEM. In all cases, if an error occurs the state
11528
** of the final contents of the changegroup is undefined.
11529
**
11530
** If no error occurs, SQLITE_OK is returned.
11531
*/
11532
SQLITE_API int sqlite3changegroup_add(sqlite3_changegroup*, int nData, void *pData);
11533
11534
/*
11535
** CAPI3REF: Obtain A Composite Changeset From A Changegroup
11536
** METHOD: sqlite3_changegroup
11537
**
11538
** Obtain a buffer containing a changeset (or patchset) representing the
11539
** current contents of the changegroup. If the inputs to the changegroup
11540
** were themselves changesets, the output is a changeset. Or, if the
11541
** inputs were patchsets, the output is also a patchset.
11542
**
11543
** As with the output of the sqlite3session_changeset() and
11544
** sqlite3session_patchset() functions, all changes related to a single
11545
** table are grouped together in the output of this function. Tables appear
11546
** in the same order as for the very first changeset added to the changegroup.
11547
** If the second or subsequent changesets added to the changegroup contain
11548
** changes for tables that do not appear in the first changeset, they are
11549
** appended onto the end of the output changeset, again in the order in
11550
** which they are first encountered.
11551
**
11552
** If an error occurs, an SQLite error code is returned and the output
11553
** variables (*pnData) and (*ppData) are set to 0. Otherwise, SQLITE_OK
11554
** is returned and the output variables are set to the size of and a
11555
** pointer to the output buffer, respectively. In this case it is the
11556
** responsibility of the caller to eventually free the buffer using a
11557
** call to sqlite3_free().
11558
*/
11559
SQLITE_API int sqlite3changegroup_output(
11560
  sqlite3_changegroup*,
11561
  int *pnData,                    /* OUT: Size of output buffer in bytes */
11562
  void **ppData                   /* OUT: Pointer to output buffer */
11563
);
11564
11565
/*
11566
** CAPI3REF: Delete A Changegroup Object
11567
** DESTRUCTOR: sqlite3_changegroup
11568
*/
11569
SQLITE_API void sqlite3changegroup_delete(sqlite3_changegroup*);
11570
11571
/*
11572
** CAPI3REF: Apply A Changeset To A Database
11573
**
11574
** Apply a changeset or patchset to a database. These functions attempt to
11575
** update the "main" database attached to handle db with the changes found in
11576
** the changeset passed via the second and third arguments.
11577
**
11578
** The fourth argument (xFilter) passed to these functions is the "filter
11579
** callback". If it is not NULL, then for each table affected by at least one
11580
** change in the changeset, the filter callback is invoked with
11581
** the table name as the second argument, and a copy of the context pointer
11582
** passed as the sixth argument as the first. If the "filter callback"
11583
** returns zero, then no attempt is made to apply any changes to the table.
11584
** Otherwise, if the return value is non-zero or the xFilter argument to
11585
** is NULL, all changes related to the table are attempted.
11586
**
11587
** For each table that is not excluded by the filter callback, this function
11588
** tests that the target database contains a compatible table. A table is
11589
** considered compatible if all of the following are true:
11590
**
11591
** <ul>
11592
**   <li> The table has the same name as the name recorded in the
11593
**        changeset, and
11594
**   <li> The table has at least as many columns as recorded in the
11595
**        changeset, and
11596
**   <li> The table has primary key columns in the same position as
11597
**        recorded in the changeset.
11598
** </ul>
11599
**
11600
** If there is no compatible table, it is not an error, but none of the
11601
** changes associated with the table are applied. A warning message is issued
11602
** via the sqlite3_log() mechanism with the error code SQLITE_SCHEMA. At most
11603
** one such warning is issued for each table in the changeset.
11604
**
11605
** For each change for which there is a compatible table, an attempt is made
11606
** to modify the table contents according to the UPDATE, INSERT or DELETE
11607
** change. If a change cannot be applied cleanly, the conflict handler
11608
** function passed as the fifth argument to sqlite3changeset_apply() may be
11609
** invoked. A description of exactly when the conflict handler is invoked for
11610
** each type of change is below.
11611
**
11612
** Unlike the xFilter argument, xConflict may not be passed NULL. The results
11613
** of passing anything other than a valid function pointer as the xConflict
11614
** argument are undefined.
11615
**
11616
** Each time the conflict handler function is invoked, it must return one
11617
** of [SQLITE_CHANGESET_OMIT], [SQLITE_CHANGESET_ABORT] or
11618
** [SQLITE_CHANGESET_REPLACE]. SQLITE_CHANGESET_REPLACE may only be returned
11619
** if the second argument passed to the conflict handler is either
11620
** SQLITE_CHANGESET_DATA or SQLITE_CHANGESET_CONFLICT. If the conflict-handler
11621
** returns an illegal value, any changes already made are rolled back and
11622
** the call to sqlite3changeset_apply() returns SQLITE_MISUSE. Different
11623
** actions are taken by sqlite3changeset_apply() depending on the value
11624
** returned by each invocation of the conflict-handler function. Refer to
11625
** the documentation for the three
11626
** [SQLITE_CHANGESET_OMIT|available return values] for details.
11627
**
11628
** <dl>
11629
** <dt>DELETE Changes<dd>
11630
**   For each DELETE change, the function checks if the target database
11631
**   contains a row with the same primary key value (or values) as the
11632
**   original row values stored in the changeset. If it does, and the values
11633
**   stored in all non-primary key columns also match the values stored in
11634
**   the changeset the row is deleted from the target database.
11635
**
11636
**   If a row with matching primary key values is found, but one or more of
11637
**   the non-primary key fields contains a value different from the original
11638
**   row value stored in the changeset, the conflict-handler function is
11639
**   invoked with [SQLITE_CHANGESET_DATA] as the second argument. If the
11640
**   database table has more columns than are recorded in the changeset,
11641
**   only the values of those non-primary key fields are compared against
11642
**   the current database contents - any trailing database table columns
11643
**   are ignored.
11644
**
11645
**   If no row with matching primary key values is found in the database,
11646
**   the conflict-handler function is invoked with [SQLITE_CHANGESET_NOTFOUND]
11647
**   passed as the second argument.
11648
**
11649
**   If the DELETE operation is attempted, but SQLite returns SQLITE_CONSTRAINT
11650
**   (which can only happen if a foreign key constraint is violated), the
11651
**   conflict-handler function is invoked with [SQLITE_CHANGESET_CONSTRAINT]
11652
**   passed as the second argument. This includes the case where the DELETE
11653
**   operation is attempted because an earlier call to the conflict handler
11654
**   function returned [SQLITE_CHANGESET_REPLACE].
11655
**
11656
** <dt>INSERT Changes<dd>
11657
**   For each INSERT change, an attempt is made to insert the new row into
11658
**   the database. If the changeset row contains fewer fields than the
11659
**   database table, the trailing fields are populated with their default
11660
**   values.
11661
**
11662
**   If the attempt to insert the row fails because the database already
11663
**   contains a row with the same primary key values, the conflict handler
11664
**   function is invoked with the second argument set to
11665
**   [SQLITE_CHANGESET_CONFLICT].
11666
**
11667
**   If the attempt to insert the row fails because of some other constraint
11668
**   violation (e.g. NOT NULL or UNIQUE), the conflict handler function is
11669
**   invoked with the second argument set to [SQLITE_CHANGESET_CONSTRAINT].
11670
**   This includes the case where the INSERT operation is re-attempted because
11671
**   an earlier call to the conflict handler function returned
11672
**   [SQLITE_CHANGESET_REPLACE].
11673
**
11674
** <dt>UPDATE Changes<dd>
11675
**   For each UPDATE change, the function checks if the target database
11676
**   contains a row with the same primary key value (or values) as the
11677
**   original row values stored in the changeset. If it does, and the values
11678
**   stored in all modified non-primary key columns also match the values
11679
**   stored in the changeset the row is updated within the target database.
11680
**
11681
**   If a row with matching primary key values is found, but one or more of
11682
**   the modified non-primary key fields contains a value different from an
11683
**   original row value stored in the changeset, the conflict-handler function
11684
**   is invoked with [SQLITE_CHANGESET_DATA] as the second argument. Since
11685
**   UPDATE changes only contain values for non-primary key fields that are
11686
**   to be modified, only those fields need to match the original values to
11687
**   avoid the SQLITE_CHANGESET_DATA conflict-handler callback.
11688
**
11689
**   If no row with matching primary key values is found in the database,
11690
**   the conflict-handler function is invoked with [SQLITE_CHANGESET_NOTFOUND]
11691
**   passed as the second argument.
11692
**
11693
**   If the UPDATE operation is attempted, but SQLite returns
11694
**   SQLITE_CONSTRAINT, the conflict-handler function is invoked with
11695
**   [SQLITE_CHANGESET_CONSTRAINT] passed as the second argument.
11696
**   This includes the case where the UPDATE operation is attempted after
11697
**   an earlier call to the conflict handler function returned
11698
**   [SQLITE_CHANGESET_REPLACE].
11699
** </dl>
11700
**
11701
** It is safe to execute SQL statements, including those that write to the
11702
** table that the callback related to, from within the xConflict callback.
11703
** This can be used to further customize the application's conflict
11704
** resolution strategy.
11705
**
11706
** All changes made by these functions are enclosed in a savepoint transaction.
11707
** If any other error (aside from a constraint failure when attempting to
11708
** write to the target database) occurs, then the savepoint transaction is
11709
** rolled back, restoring the target database to its original state, and an
11710
** SQLite error code returned.
11711
**
11712
** If the output parameters (ppRebase) and (pnRebase) are non-NULL and
11713
** the input is a changeset (not a patchset), then sqlite3changeset_apply_v2()
11714
** may set (*ppRebase) to point to a "rebase" that may be used with the
11715
** sqlite3_rebaser APIs buffer before returning. In this case (*pnRebase)
11716
** is set to the size of the buffer in bytes. It is the responsibility of the
11717
** caller to eventually free any such buffer using sqlite3_free(). The buffer
11718
** is only allocated and populated if one or more conflicts were encountered
11719
** while applying the patchset. See comments surrounding the sqlite3_rebaser
11720
** APIs for further details.
11721
**
11722
** The behavior of sqlite3changeset_apply_v2() and its streaming equivalent
11723
** may be modified by passing a combination of
11724
** [SQLITE_CHANGESETAPPLY_NOSAVEPOINT | supported flags] as the 9th parameter.
11725
**
11726
** Note that the sqlite3changeset_apply_v2() API is still <b>experimental</b>
11727
** and therefore subject to change.
11728
*/
11729
SQLITE_API int sqlite3changeset_apply(
11730
  sqlite3 *db,                    /* Apply change to "main" db of this handle */
11731
  int nChangeset,                 /* Size of changeset in bytes */
11732
  void *pChangeset,               /* Changeset blob */
11733
  int(*xFilter)(
11734
    void *pCtx,                   /* Copy of sixth arg to _apply() */
11735
    const char *zTab              /* Table name */
11736
  ),
11737
  int(*xConflict)(
11738
    void *pCtx,                   /* Copy of sixth arg to _apply() */
11739
    int eConflict,                /* DATA, MISSING, CONFLICT, CONSTRAINT */
11740
    sqlite3_changeset_iter *p     /* Handle describing change and conflict */
11741
  ),
11742
  void *pCtx                      /* First argument passed to xConflict */
11743
);
11744
SQLITE_API int sqlite3changeset_apply_v2(
11745
  sqlite3 *db,                    /* Apply change to "main" db of this handle */
11746
  int nChangeset,                 /* Size of changeset in bytes */
11747
  void *pChangeset,               /* Changeset blob */
11748
  int(*xFilter)(
11749
    void *pCtx,                   /* Copy of sixth arg to _apply() */
11750
    const char *zTab              /* Table name */
11751
  ),
11752
  int(*xConflict)(
11753
    void *pCtx,                   /* Copy of sixth arg to _apply() */
11754
    int eConflict,                /* DATA, MISSING, CONFLICT, CONSTRAINT */
11755
    sqlite3_changeset_iter *p     /* Handle describing change and conflict */
11756
  ),
11757
  void *pCtx,                     /* First argument passed to xConflict */
11758
  void **ppRebase, int *pnRebase, /* OUT: Rebase data */
11759
  int flags                       /* SESSION_CHANGESETAPPLY_* flags */
11760
);
11761
11762
/*
11763
** CAPI3REF: Flags for sqlite3changeset_apply_v2
11764
**
11765
** The following flags may passed via the 9th parameter to
11766
** [sqlite3changeset_apply_v2] and [sqlite3changeset_apply_v2_strm]:
11767
**
11768
** <dl>
11769
** <dt>SQLITE_CHANGESETAPPLY_NOSAVEPOINT <dd>
11770
**   Usually, the sessions module encloses all operations performed by
11771
**   a single call to apply_v2() or apply_v2_strm() in a [SAVEPOINT]. The
11772
**   SAVEPOINT is committed if the changeset or patchset is successfully
11773
**   applied, or rolled back if an error occurs. Specifying this flag
11774
**   causes the sessions module to omit this savepoint. In this case, if the
11775
**   caller has an open transaction or savepoint when apply_v2() is called,
11776
**   it may revert the partially applied changeset by rolling it back.
11777
**
11778
** <dt>SQLITE_CHANGESETAPPLY_INVERT <dd>
11779
**   Invert the changeset before applying it. This is equivalent to inverting
11780
**   a changeset using sqlite3changeset_invert() before applying it. It is
11781
**   an error to specify this flag with a patchset.
11782
*/
11783
#define SQLITE_CHANGESETAPPLY_NOSAVEPOINT   0x0001
11784
#define SQLITE_CHANGESETAPPLY_INVERT        0x0002
11785
11786
/*
11787
** CAPI3REF: Constants Passed To The Conflict Handler
11788
**
11789
** Values that may be passed as the second argument to a conflict-handler.
11790
**
11791
** <dl>
11792
** <dt>SQLITE_CHANGESET_DATA<dd>
11793
**   The conflict handler is invoked with CHANGESET_DATA as the second argument
11794
**   when processing a DELETE or UPDATE change if a row with the required
11795
**   PRIMARY KEY fields is present in the database, but one or more other
11796
**   (non primary-key) fields modified by the update do not contain the
11797
**   expected "before" values.
11798
**
11799
**   The conflicting row, in this case, is the database row with the matching
11800
**   primary key.
11801
**
11802
** <dt>SQLITE_CHANGESET_NOTFOUND<dd>
11803
**   The conflict handler is invoked with CHANGESET_NOTFOUND as the second
11804
**   argument when processing a DELETE or UPDATE change if a row with the
11805
**   required PRIMARY KEY fields is not present in the database.
11806
**
11807
**   There is no conflicting row in this case. The results of invoking the
11808
**   sqlite3changeset_conflict() API are undefined.
11809
**
11810
** <dt>SQLITE_CHANGESET_CONFLICT<dd>
11811
**   CHANGESET_CONFLICT is passed as the second argument to the conflict
11812
**   handler while processing an INSERT change if the operation would result
11813
**   in duplicate primary key values.
11814
**
11815
**   The conflicting row in this case is the database row with the matching
11816
**   primary key.
11817
**
11818
** <dt>SQLITE_CHANGESET_FOREIGN_KEY<dd>
11819
**   If foreign key handling is enabled, and applying a changeset leaves the
11820
**   database in a state containing foreign key violations, the conflict
11821
**   handler is invoked with CHANGESET_FOREIGN_KEY as the second argument
11822
**   exactly once before the changeset is committed. If the conflict handler
11823
**   returns CHANGESET_OMIT, the changes, including those that caused the
11824
**   foreign key constraint violation, are committed. Or, if it returns
11825
**   CHANGESET_ABORT, the changeset is rolled back.
11826
**
11827
**   No current or conflicting row information is provided. The only function
11828
**   it is possible to call on the supplied sqlite3_changeset_iter handle
11829
**   is sqlite3changeset_fk_conflicts().
11830
**
11831
** <dt>SQLITE_CHANGESET_CONSTRAINT<dd>
11832
**   If any other constraint violation occurs while applying a change (i.e.
11833
**   a UNIQUE, CHECK or NOT NULL constraint), the conflict handler is
11834
**   invoked with CHANGESET_CONSTRAINT as the second argument.
11835
**
11836
**   There is no conflicting row in this case. The results of invoking the
11837
**   sqlite3changeset_conflict() API are undefined.
11838
**
11839
** </dl>
11840
*/
11841
#define SQLITE_CHANGESET_DATA        1
11842
#define SQLITE_CHANGESET_NOTFOUND    2
11843
#define SQLITE_CHANGESET_CONFLICT    3
11844
#define SQLITE_CHANGESET_CONSTRAINT  4
11845
#define SQLITE_CHANGESET_FOREIGN_KEY 5
11846
11847
/*
11848
** CAPI3REF: Constants Returned By The Conflict Handler
11849
**
11850
** A conflict handler callback must return one of the following three values.
11851
**
11852
** <dl>
11853
** <dt>SQLITE_CHANGESET_OMIT<dd>
11854
**   If a conflict handler returns this value no special action is taken. The
11855
**   change that caused the conflict is not applied. The session module
11856
**   continues to the next change in the changeset.
11857
**
11858
** <dt>SQLITE_CHANGESET_REPLACE<dd>
11859
**   This value may only be returned if the second argument to the conflict
11860
**   handler was SQLITE_CHANGESET_DATA or SQLITE_CHANGESET_CONFLICT. If this
11861
**   is not the case, any changes applied so far are rolled back and the
11862
**   call to sqlite3changeset_apply() returns SQLITE_MISUSE.
11863
**
11864
**   If CHANGESET_REPLACE is returned by an SQLITE_CHANGESET_DATA conflict
11865
**   handler, then the conflicting row is either updated or deleted, depending
11866
**   on the type of change.
11867
**
11868
**   If CHANGESET_REPLACE is returned by an SQLITE_CHANGESET_CONFLICT conflict
11869
**   handler, then the conflicting row is removed from the database and a
11870
**   second attempt to apply the change is made. If this second attempt fails,
11871
**   the original row is restored to the database before continuing.
11872
**
11873
** <dt>SQLITE_CHANGESET_ABORT<dd>
11874
**   If this value is returned, any changes applied so far are rolled back
11875
**   and the call to sqlite3changeset_apply() returns SQLITE_ABORT.
11876
** </dl>
11877
*/
11878
#define SQLITE_CHANGESET_OMIT       0
11879
#define SQLITE_CHANGESET_REPLACE    1
11880
#define SQLITE_CHANGESET_ABORT      2
11881
11882
/*
11883
** CAPI3REF: Rebasing changesets
11884
** EXPERIMENTAL
11885
**
11886
** Suppose there is a site hosting a database in state S0. And that
11887
** modifications are made that move that database to state S1 and a
11888
** changeset recorded (the "local" changeset). Then, a changeset based
11889
** on S0 is received from another site (the "remote" changeset) and
11890
** applied to the database. The database is then in state
11891
** (S1+"remote"), where the exact state depends on any conflict
11892
** resolution decisions (OMIT or REPLACE) made while applying "remote".
11893
** Rebasing a changeset is to update it to take those conflict
11894
** resolution decisions into account, so that the same conflicts
11895
** do not have to be resolved elsewhere in the network.
11896
**
11897
** For example, if both the local and remote changesets contain an
11898
** INSERT of the same key on "CREATE TABLE t1(a PRIMARY KEY, b)":
11899
**
11900
**   local:  INSERT INTO t1 VALUES(1, 'v1');
11901
**   remote: INSERT INTO t1 VALUES(1, 'v2');
11902
**
11903
** and the conflict resolution is REPLACE, then the INSERT change is
11904
** removed from the local changeset (it was overridden). Or, if the
11905
** conflict resolution was "OMIT", then the local changeset is modified
11906
** to instead contain:
11907
**
11908
**           UPDATE t1 SET b = 'v2' WHERE a=1;
11909
**
11910
** Changes within the local changeset are rebased as follows:
11911
**
11912
** <dl>
11913
** <dt>Local INSERT<dd>
11914
**   This may only conflict with a remote INSERT. If the conflict
11915
**   resolution was OMIT, then add an UPDATE change to the rebased
11916
**   changeset. Or, if the conflict resolution was REPLACE, add
11917
**   nothing to the rebased changeset.
11918
**
11919
** <dt>Local DELETE<dd>
11920
**   This may conflict with a remote UPDATE or DELETE. In both cases the
11921
**   only possible resolution is OMIT. If the remote operation was a
11922
**   DELETE, then add no change to the rebased changeset. If the remote
11923
**   operation was an UPDATE, then the old.* fields of change are updated
11924
**   to reflect the new.* values in the UPDATE.
11925
**
11926
** <dt>Local UPDATE<dd>
11927
**   This may conflict with a remote UPDATE or DELETE. If it conflicts
11928
**   with a DELETE, and the conflict resolution was OMIT, then the update
11929
**   is changed into an INSERT. Any undefined values in the new.* record
11930
**   from the update change are filled in using the old.* values from
11931
**   the conflicting DELETE. Or, if the conflict resolution was REPLACE,
11932
**   the UPDATE change is simply omitted from the rebased changeset.
11933
**
11934
**   If conflict is with a remote UPDATE and the resolution is OMIT, then
11935
**   the old.* values are rebased using the new.* values in the remote
11936
**   change. Or, if the resolution is REPLACE, then the change is copied
11937
**   into the rebased changeset with updates to columns also updated by
11938
**   the conflicting remote UPDATE removed. If this means no columns would
11939
**   be updated, the change is omitted.
11940
** </dl>
11941
**
11942
** A local change may be rebased against multiple remote changes
11943
** simultaneously. If a single key is modified by multiple remote
11944
** changesets, they are combined as follows before the local changeset
11945
** is rebased:
11946
**
11947
** <ul>
11948
**    <li> If there has been one or more REPLACE resolutions on a
11949
**         key, it is rebased according to a REPLACE.
11950
**
11951
**    <li> If there have been no REPLACE resolutions on a key, then
11952
**         the local changeset is rebased according to the most recent
11953
**         of the OMIT resolutions.
11954
** </ul>
11955
**
11956
** Note that conflict resolutions from multiple remote changesets are
11957
** combined on a per-field basis, not per-row. This means that in the
11958
** case of multiple remote UPDATE operations, some fields of a single
11959
** local change may be rebased for REPLACE while others are rebased for
11960
** OMIT.
11961
**
11962
** In order to rebase a local changeset, the remote changeset must first
11963
** be applied to the local database using sqlite3changeset_apply_v2() and
11964
** the buffer of rebase information captured. Then:
11965
**
11966
** <ol>
11967
**   <li> An sqlite3_rebaser object is created by calling
11968
**        sqlite3rebaser_create().
11969
**   <li> The new object is configured with the rebase buffer obtained from
11970
**        sqlite3changeset_apply_v2() by calling sqlite3rebaser_configure().
11971
**        If the local changeset is to be rebased against multiple remote
11972
**        changesets, then sqlite3rebaser_configure() should be called
11973
**        multiple times, in the same order that the multiple
11974
**        sqlite3changeset_apply_v2() calls were made.
11975
**   <li> Each local changeset is rebased by calling sqlite3rebaser_rebase().
11976
**   <li> The sqlite3_rebaser object is deleted by calling
11977
**        sqlite3rebaser_delete().
11978
** </ol>
11979
*/
11980
typedef struct sqlite3_rebaser sqlite3_rebaser;
11981
11982
/*
11983
** CAPI3REF: Create a changeset rebaser object.
11984
** EXPERIMENTAL
11985
**
11986
** Allocate a new changeset rebaser object. If successful, set (*ppNew) to
11987
** point to the new object and return SQLITE_OK. Otherwise, if an error
11988
** occurs, return an SQLite error code (e.g. SQLITE_NOMEM) and set (*ppNew)
11989
** to NULL.
11990
*/
11991
SQLITE_API int sqlite3rebaser_create(sqlite3_rebaser **ppNew);
11992
11993
/*
11994
** CAPI3REF: Configure a changeset rebaser object.
11995
** EXPERIMENTAL
11996
**
11997
** Configure the changeset rebaser object to rebase changesets according
11998
** to the conflict resolutions described by buffer pRebase (size nRebase
11999
** bytes), which must have been obtained from a previous call to
12000
** sqlite3changeset_apply_v2().
12001
*/
12002
SQLITE_API int sqlite3rebaser_configure(
12003
  sqlite3_rebaser*,
12004
  int nRebase, const void *pRebase
12005
);
12006
12007
/*
12008
** CAPI3REF: Rebase a changeset
12009
** EXPERIMENTAL
12010
**
12011
** Argument pIn must point to a buffer containing a changeset nIn bytes
12012
** in size. This function allocates and populates a buffer with a copy
12013
** of the changeset rebased according to the configuration of the
12014
** rebaser object passed as the first argument. If successful, (*ppOut)
12015
** is set to point to the new buffer containing the rebased changeset and
12016
** (*pnOut) to its size in bytes and SQLITE_OK returned. It is the
12017
** responsibility of the caller to eventually free the new buffer using
12018
** sqlite3_free(). Otherwise, if an error occurs, (*ppOut) and (*pnOut)
12019
** are set to zero and an SQLite error code returned.
12020
*/
12021
SQLITE_API int sqlite3rebaser_rebase(
12022
  sqlite3_rebaser*,
12023
  int nIn, const void *pIn,
12024
  int *pnOut, void **ppOut
12025
);
12026
12027
/*
12028
** CAPI3REF: Delete a changeset rebaser object.
12029
** EXPERIMENTAL
12030
**
12031
** Delete the changeset rebaser object and all associated resources. There
12032
** should be one call to this function for each successful invocation
12033
** of sqlite3rebaser_create().
12034
*/
12035
SQLITE_API void sqlite3rebaser_delete(sqlite3_rebaser *p);
12036
12037
/*
12038
** CAPI3REF: Streaming Versions of API functions.
12039
**
12040
** The six streaming API xxx_strm() functions serve similar purposes to the
12041
** corresponding non-streaming API functions:
12042
**
12043
** <table border=1 style="margin-left:8ex;margin-right:8ex">
12044
**   <tr><th>Streaming function<th>Non-streaming equivalent</th>
12045
**   <tr><td>sqlite3changeset_apply_strm<td>[sqlite3changeset_apply]
12046
**   <tr><td>sqlite3changeset_apply_strm_v2<td>[sqlite3changeset_apply_v2]
12047
**   <tr><td>sqlite3changeset_concat_strm<td>[sqlite3changeset_concat]
12048
**   <tr><td>sqlite3changeset_invert_strm<td>[sqlite3changeset_invert]
12049
**   <tr><td>sqlite3changeset_start_strm<td>[sqlite3changeset_start]
12050
**   <tr><td>sqlite3session_changeset_strm<td>[sqlite3session_changeset]
12051
**   <tr><td>sqlite3session_patchset_strm<td>[sqlite3session_patchset]
12052
** </table>
12053
**
12054
** Non-streaming functions that accept changesets (or patchsets) as input
12055
** require that the entire changeset be stored in a single buffer in memory.
12056
** Similarly, those that return a changeset or patchset do so by returning
12057
** a pointer to a single large buffer allocated using sqlite3_malloc().
12058
** Normally this is convenient. However, if an application running in a
12059
** low-memory environment is required to handle very large changesets, the
12060
** large contiguous memory allocations required can become onerous.
12061
**
12062
** In order to avoid this problem, instead of a single large buffer, input
12063
** is passed to a streaming API functions by way of a callback function that
12064
** the sessions module invokes to incrementally request input data as it is
12065
** required. In all cases, a pair of API function parameters such as
12066
**
12067
**  <pre>
12068
**  &nbsp;     int nChangeset,
12069
**  &nbsp;     void *pChangeset,
12070
**  </pre>
12071
**
12072
** Is replaced by:
12073
**
12074
**  <pre>
12075
**  &nbsp;     int (*xInput)(void *pIn, void *pData, int *pnData),
12076
**  &nbsp;     void *pIn,
12077
**  </pre>
12078
**
12079
** Each time the xInput callback is invoked by the sessions module, the first
12080
** argument passed is a copy of the supplied pIn context pointer. The second
12081
** argument, pData, points to a buffer (*pnData) bytes in size. Assuming no
12082
** error occurs the xInput method should copy up to (*pnData) bytes of data
12083
** into the buffer and set (*pnData) to the actual number of bytes copied
12084
** before returning SQLITE_OK. If the input is completely exhausted, (*pnData)
12085
** should be set to zero to indicate this. Or, if an error occurs, an SQLite
12086
** error code should be returned. In all cases, if an xInput callback returns
12087
** an error, all processing is abandoned and the streaming API function
12088
** returns a copy of the error code to the caller.
12089
**
12090
** In the case of sqlite3changeset_start_strm(), the xInput callback may be
12091
** invoked by the sessions module at any point during the lifetime of the
12092
** iterator. If such an xInput callback returns an error, the iterator enters
12093
** an error state, whereby all subsequent calls to iterator functions
12094
** immediately fail with the same error code as returned by xInput.
12095
**
12096
** Similarly, streaming API functions that return changesets (or patchsets)
12097
** return them in chunks by way of a callback function instead of via a
12098
** pointer to a single large buffer. In this case, a pair of parameters such
12099
** as:
12100
**
12101
**  <pre>
12102
**  &nbsp;     int *pnChangeset,
12103
**  &nbsp;     void **ppChangeset,
12104
**  </pre>
12105
**
12106
** Is replaced by:
12107
**
12108
**  <pre>
12109
**  &nbsp;     int (*xOutput)(void *pOut, const void *pData, int nData),
12110
**  &nbsp;     void *pOut
12111
**  </pre>
12112
**
12113
** The xOutput callback is invoked zero or more times to return data to
12114
** the application. The first parameter passed to each call is a copy of the
12115
** pOut pointer supplied by the application. The second parameter, pData,
12116
** points to a buffer nData bytes in size containing the chunk of output
12117
** data being returned. If the xOutput callback successfully processes the
12118
** supplied data, it should return SQLITE_OK to indicate success. Otherwise,
12119
** it should return some other SQLite error code. In this case processing
12120
** is immediately abandoned and the streaming API function returns a copy
12121
** of the xOutput error code to the application.
12122
**
12123
** The sessions module never invokes an xOutput callback with the third
12124
** parameter set to a value less than or equal to zero. Other than this,
12125
** no guarantees are made as to the size of the chunks of data returned.
12126
*/
12127
SQLITE_API int sqlite3changeset_apply_strm(
12128
  sqlite3 *db,                    /* Apply change to "main" db of this handle */
12129
  int (*xInput)(void *pIn, void *pData, int *pnData), /* Input function */
12130
  void *pIn,                                          /* First arg for xInput */
12131
  int(*xFilter)(
12132
    void *pCtx,                   /* Copy of sixth arg to _apply() */
12133
    const char *zTab              /* Table name */
12134
  ),
12135
  int(*xConflict)(
12136
    void *pCtx,                   /* Copy of sixth arg to _apply() */
12137
    int eConflict,                /* DATA, MISSING, CONFLICT, CONSTRAINT */
12138
    sqlite3_changeset_iter *p     /* Handle describing change and conflict */
12139
  ),
12140
  void *pCtx                      /* First argument passed to xConflict */
12141
);
12142
SQLITE_API int sqlite3changeset_apply_v2_strm(
12143
  sqlite3 *db,                    /* Apply change to "main" db of this handle */
12144
  int (*xInput)(void *pIn, void *pData, int *pnData), /* Input function */
12145
  void *pIn,                                          /* First arg for xInput */
12146
  int(*xFilter)(
12147
    void *pCtx,                   /* Copy of sixth arg to _apply() */
12148
    const char *zTab              /* Table name */
12149
  ),
12150
  int(*xConflict)(
12151
    void *pCtx,                   /* Copy of sixth arg to _apply() */
12152
    int eConflict,                /* DATA, MISSING, CONFLICT, CONSTRAINT */
12153
    sqlite3_changeset_iter *p     /* Handle describing change and conflict */
12154
  ),
12155
  void *pCtx,                     /* First argument passed to xConflict */
12156
  void **ppRebase, int *pnRebase,
12157
  int flags
12158
);
12159
SQLITE_API int sqlite3changeset_concat_strm(
12160
  int (*xInputA)(void *pIn, void *pData, int *pnData),
12161
  void *pInA,
12162
  int (*xInputB)(void *pIn, void *pData, int *pnData),
12163
  void *pInB,
12164
  int (*xOutput)(void *pOut, const void *pData, int nData),
12165
  void *pOut
12166
);
12167
SQLITE_API int sqlite3changeset_invert_strm(
12168
  int (*xInput)(void *pIn, void *pData, int *pnData),
12169
  void *pIn,
12170
  int (*xOutput)(void *pOut, const void *pData, int nData),
12171
  void *pOut
12172
);
12173
SQLITE_API int sqlite3changeset_start_strm(
12174
  sqlite3_changeset_iter **pp,
12175
  int (*xInput)(void *pIn, void *pData, int *pnData),
12176
  void *pIn
12177
);
12178
SQLITE_API int sqlite3changeset_start_v2_strm(
12179
  sqlite3_changeset_iter **pp,
12180
  int (*xInput)(void *pIn, void *pData, int *pnData),
12181
  void *pIn,
12182
  int flags
12183
);
12184
SQLITE_API int sqlite3session_changeset_strm(
12185
  sqlite3_session *pSession,
12186
  int (*xOutput)(void *pOut, const void *pData, int nData),
12187
  void *pOut
12188
);
12189
SQLITE_API int sqlite3session_patchset_strm(
12190
  sqlite3_session *pSession,
12191
  int (*xOutput)(void *pOut, const void *pData, int nData),
12192
  void *pOut
12193
);
12194
SQLITE_API int sqlite3changegroup_add_strm(sqlite3_changegroup*,
12195
    int (*xInput)(void *pIn, void *pData, int *pnData),
12196
    void *pIn
12197
);
12198
SQLITE_API int sqlite3changegroup_output_strm(sqlite3_changegroup*,
12199
    int (*xOutput)(void *pOut, const void *pData, int nData),
12200
    void *pOut
12201
);
12202
SQLITE_API int sqlite3rebaser_rebase_strm(
12203
  sqlite3_rebaser *pRebaser,
12204
  int (*xInput)(void *pIn, void *pData, int *pnData),
12205
  void *pIn,
12206
  int (*xOutput)(void *pOut, const void *pData, int nData),
12207
  void *pOut
12208
);
12209
12210
/*
12211
** CAPI3REF: Configure global parameters
12212
**
12213
** The sqlite3session_config() interface is used to make global configuration
12214
** changes to the sessions module in order to tune it to the specific needs
12215
** of the application.
12216
**
12217
** The sqlite3session_config() interface is not threadsafe. If it is invoked
12218
** while any other thread is inside any other sessions method then the
12219
** results are undefined. Furthermore, if it is invoked after any sessions
12220
** related objects have been created, the results are also undefined.
12221
**
12222
** The first argument to the sqlite3session_config() function must be one
12223
** of the SQLITE_SESSION_CONFIG_XXX constants defined below. The
12224
** interpretation of the (void*) value passed as the second parameter and
12225
** the effect of calling this function depends on the value of the first
12226
** parameter.
12227
**
12228
** <dl>
12229
** <dt>SQLITE_SESSION_CONFIG_STRMSIZE<dd>
12230
**    By default, the sessions module streaming interfaces attempt to input
12231
**    and output data in approximately 1 KiB chunks. This operand may be used
12232
**    to set and query the value of this configuration setting. The pointer
12233
**    passed as the second argument must point to a value of type (int).
12234
**    If this value is greater than 0, it is used as the new streaming data
12235
**    chunk size for both input and output. Before returning, the (int) value
12236
**    pointed to by pArg is set to the final value of the streaming interface
12237
**    chunk size.
12238
** </dl>
12239
**
12240
** This function returns SQLITE_OK if successful, or an SQLite error code
12241
** otherwise.
12242
*/
12243
SQLITE_API int sqlite3session_config(int op, void *pArg);
12244
12245
/*
12246
** CAPI3REF: Values for sqlite3session_config().
12247
*/
12248
#define SQLITE_SESSION_CONFIG_STRMSIZE 1
12249
12250
/*
12251
** Make sure we can call this stuff from C++.
12252
*/
12253
#ifdef __cplusplus
12254
}
12255
#endif
12256
12257
#endif  /* !defined(__SQLITESESSION_H_) && defined(SQLITE_ENABLE_SESSION) */
12258
12259
/******** End of sqlite3session.h *********/
12260
/******** Begin file fts5.h *********/
12261
/*
12262
** 2014 May 31
12263
**
12264
** The author disclaims copyright to this source code.  In place of
12265
** a legal notice, here is a blessing:
12266
**
12267
**    May you do good and not evil.
12268
**    May you find forgiveness for yourself and forgive others.
12269
**    May you share freely, never taking more than you give.
12270
**
12271
******************************************************************************
12272
**
12273
** Interfaces to extend FTS5. Using the interfaces defined in this file,
12274
** FTS5 may be extended with:
12275
**
12276
**     * custom tokenizers, and
12277
**     * custom auxiliary functions.
12278
*/
12279
12280
12281
#ifndef _FTS5_H
12282
#define _FTS5_H
12283
12284
12285
#ifdef __cplusplus
12286
extern "C" {
12287
#endif
12288
12289
/*************************************************************************
12290
** CUSTOM AUXILIARY FUNCTIONS
12291
**
12292
** Virtual table implementations may overload SQL functions by implementing
12293
** the sqlite3_module.xFindFunction() method.
12294
*/
12295
12296
typedef struct Fts5ExtensionApi Fts5ExtensionApi;
12297
typedef struct Fts5Context Fts5Context;
12298
typedef struct Fts5PhraseIter Fts5PhraseIter;
12299
12300
typedef void (*fts5_extension_function)(
12301
  const Fts5ExtensionApi *pApi,   /* API offered by current FTS version */
12302
  Fts5Context *pFts,              /* First arg to pass to pApi functions */
12303
  sqlite3_context *pCtx,          /* Context for returning result/error */
12304
  int nVal,                       /* Number of values in apVal[] array */
12305
  sqlite3_value **apVal           /* Array of trailing arguments */
12306
);
12307
12308
struct Fts5PhraseIter {
12309
  const unsigned char *a;
12310
  const unsigned char *b;
12311
};
12312
12313
/*
12314
** EXTENSION API FUNCTIONS
12315
**
12316
** xUserData(pFts):
12317
**   Return a copy of the context pointer the extension function was
12318
**   registered with.
12319
**
12320
** xColumnTotalSize(pFts, iCol, pnToken):
12321
**   If parameter iCol is less than zero, set output variable *pnToken
12322
**   to the total number of tokens in the FTS5 table. Or, if iCol is
12323
**   non-negative but less than the number of columns in the table, return
12324
**   the total number of tokens in column iCol, considering all rows in
12325
**   the FTS5 table.
12326
**
12327
**   If parameter iCol is greater than or equal to the number of columns
12328
**   in the table, SQLITE_RANGE is returned. Or, if an error occurs (e.g.
12329
**   an OOM condition or IO error), an appropriate SQLite error code is
12330
**   returned.
12331
**
12332
** xColumnCount(pFts):
12333
**   Return the number of columns in the table.
12334
**
12335
** xColumnSize(pFts, iCol, pnToken):
12336
**   If parameter iCol is less than zero, set output variable *pnToken
12337
**   to the total number of tokens in the current row. Or, if iCol is
12338
**   non-negative but less than the number of columns in the table, set
12339
**   *pnToken to the number of tokens in column iCol of the current row.
12340
**
12341
**   If parameter iCol is greater than or equal to the number of columns
12342
**   in the table, SQLITE_RANGE is returned. Or, if an error occurs (e.g.
12343
**   an OOM condition or IO error), an appropriate SQLite error code is
12344
**   returned.
12345
**
12346
**   This function may be quite inefficient if used with an FTS5 table
12347
**   created with the "columnsize=0" option.
12348
**
12349
** xColumnText:
12350
**   This function attempts to retrieve the text of column iCol of the
12351
**   current document. If successful, (*pz) is set to point to a buffer
12352
**   containing the text in utf-8 encoding, (*pn) is set to the size in bytes
12353
**   (not characters) of the buffer and SQLITE_OK is returned. Otherwise,
12354
**   if an error occurs, an SQLite error code is returned and the final values
12355
**   of (*pz) and (*pn) are undefined.
12356
**
12357
** xPhraseCount:
12358
**   Returns the number of phrases in the current query expression.
12359
**
12360
** xPhraseSize:
12361
**   Returns the number of tokens in phrase iPhrase of the query. Phrases
12362
**   are numbered starting from zero.
12363
**
12364
** xInstCount:
12365
**   Set *pnInst to the total number of occurrences of all phrases within
12366
**   the query within the current row. Return SQLITE_OK if successful, or
12367
**   an error code (i.e. SQLITE_NOMEM) if an error occurs.
12368
**
12369
**   This API can be quite slow if used with an FTS5 table created with the
12370
**   "detail=none" or "detail=column" option. If the FTS5 table is created
12371
**   with either "detail=none" or "detail=column" and "content=" option
12372
**   (i.e. if it is a contentless table), then this API always returns 0.
12373
**
12374
** xInst:
12375
**   Query for the details of phrase match iIdx within the current row.
12376
**   Phrase matches are numbered starting from zero, so the iIdx argument
12377
**   should be greater than or equal to zero and smaller than the value
12378
**   output by xInstCount().
12379
**
12380
**   Usually, output parameter *piPhrase is set to the phrase number, *piCol
12381
**   to the column in which it occurs and *piOff the token offset of the
12382
**   first token of the phrase. Returns SQLITE_OK if successful, or an error
12383
**   code (i.e. SQLITE_NOMEM) if an error occurs.
12384
**
12385
**   This API can be quite slow if used with an FTS5 table created with the
12386
**   "detail=none" or "detail=column" option.
12387
**
12388
** xRowid:
12389
**   Returns the rowid of the current row.
12390
**
12391
** xTokenize:
12392
**   Tokenize text using the tokenizer belonging to the FTS5 table.
12393
**
12394
** xQueryPhrase(pFts5, iPhrase, pUserData, xCallback):
12395
**   This API function is used to query the FTS table for phrase iPhrase
12396
**   of the current query. Specifically, a query equivalent to:
12397
**
12398
**       ... FROM ftstable WHERE ftstable MATCH $p ORDER BY rowid
12399
**
12400
**   with $p set to a phrase equivalent to the phrase iPhrase of the
12401
**   current query is executed. Any column filter that applies to
12402
**   phrase iPhrase of the current query is included in $p. For each
12403
**   row visited, the callback function passed as the fourth argument
12404
**   is invoked. The context and API objects passed to the callback
12405
**   function may be used to access the properties of each matched row.
12406
**   Invoking Api.xUserData() returns a copy of the pointer passed as
12407
**   the third argument to pUserData.
12408
**
12409
**   If the callback function returns any value other than SQLITE_OK, the
12410
**   query is abandoned and the xQueryPhrase function returns immediately.
12411
**   If the returned value is SQLITE_DONE, xQueryPhrase returns SQLITE_OK.
12412
**   Otherwise, the error code is propagated upwards.
12413
**
12414
**   If the query runs to completion without incident, SQLITE_OK is returned.
12415
**   Or, if some error occurs before the query completes or is aborted by
12416
**   the callback, an SQLite error code is returned.
12417
**
12418
**
12419
** xSetAuxdata(pFts5, pAux, xDelete)
12420
**
12421
**   Save the pointer passed as the second argument as the extension function's
12422
**   "auxiliary data". The pointer may then be retrieved by the current or any
12423
**   future invocation of the same fts5 extension function made as part of
12424
**   the same MATCH query using the xGetAuxdata() API.
12425
**
12426
**   Each extension function is allocated a single auxiliary data slot for
12427
**   each FTS query (MATCH expression). If the extension function is invoked
12428
**   more than once for a single FTS query, then all invocations share a
12429
**   single auxiliary data context.
12430
**
12431
**   If there is already an auxiliary data pointer when this function is
12432
**   invoked, then it is replaced by the new pointer. If an xDelete callback
12433
**   was specified along with the original pointer, it is invoked at this
12434
**   point.
12435
**
12436
**   The xDelete callback, if one is specified, is also invoked on the
12437
**   auxiliary data pointer after the FTS5 query has finished.
12438
**
12439
**   If an error (e.g. an OOM condition) occurs within this function,
12440
**   the auxiliary data is set to NULL and an error code returned. If the
12441
**   xDelete parameter was not NULL, it is invoked on the auxiliary data
12442
**   pointer before returning.
12443
**
12444
**
12445
** xGetAuxdata(pFts5, bClear)
12446
**
12447
**   Returns the current auxiliary data pointer for the fts5 extension
12448
**   function. See the xSetAuxdata() method for details.
12449
**
12450
**   If the bClear argument is non-zero, then the auxiliary data is cleared
12451
**   (set to NULL) before this function returns. In this case the xDelete,
12452
**   if any, is not invoked.
12453
**
12454
**
12455
** xRowCount(pFts5, pnRow)
12456
**
12457
**   This function is used to retrieve the total number of rows in the table.
12458
**   In other words, the same value that would be returned by:
12459
**
12460
**        SELECT count(*) FROM ftstable;
12461
**
12462
** xPhraseFirst()
12463
**   This function is used, along with type Fts5PhraseIter and the xPhraseNext
12464
**   method, to iterate through all instances of a single query phrase within
12465
**   the current row. This is the same information as is accessible via the
12466
**   xInstCount/xInst APIs. While the xInstCount/xInst APIs are more convenient
12467
**   to use, this API may be faster under some circumstances. To iterate
12468
**   through instances of phrase iPhrase, use the following code:
12469
**
12470
**       Fts5PhraseIter iter;
12471
**       int iCol, iOff;
12472
**       for(pApi->xPhraseFirst(pFts, iPhrase, &iter, &iCol, &iOff);
12473
**           iCol>=0;
12474
**           pApi->xPhraseNext(pFts, &iter, &iCol, &iOff)
12475
**       ){
12476
**         // An instance of phrase iPhrase at offset iOff of column iCol
12477
**       }
12478
**
12479
**   The Fts5PhraseIter structure is defined above. Applications should not
12480
**   modify this structure directly - it should only be used as shown above
12481
**   with the xPhraseFirst() and xPhraseNext() API methods (and by
12482
**   xPhraseFirstColumn() and xPhraseNextColumn() as illustrated below).
12483
**
12484
**   This API can be quite slow if used with an FTS5 table created with the
12485
**   "detail=none" or "detail=column" option. If the FTS5 table is created
12486
**   with either "detail=none" or "detail=column" and "content=" option
12487
**   (i.e. if it is a contentless table), then this API always iterates
12488
**   through an empty set (all calls to xPhraseFirst() set iCol to -1).
12489
**
12490
** xPhraseNext()
12491
**   See xPhraseFirst above.
12492
**
12493
** xPhraseFirstColumn()
12494
**   This function and xPhraseNextColumn() are similar to the xPhraseFirst()
12495
**   and xPhraseNext() APIs described above. The difference is that instead
12496
**   of iterating through all instances of a phrase in the current row, these
12497
**   APIs are used to iterate through the set of columns in the current row
12498
**   that contain one or more instances of a specified phrase. For example:
12499
**
12500
**       Fts5PhraseIter iter;
12501
**       int iCol;
12502
**       for(pApi->xPhraseFirstColumn(pFts, iPhrase, &iter, &iCol);
12503
**           iCol>=0;
12504
**           pApi->xPhraseNextColumn(pFts, &iter, &iCol)
12505
**       ){
12506
**         // Column iCol contains at least one instance of phrase iPhrase
12507
**       }
12508
**
12509
**   This API can be quite slow if used with an FTS5 table created with the
12510
**   "detail=none" option. If the FTS5 table is created with either
12511
**   "detail=none" "content=" option (i.e. if it is a contentless table),
12512
**   then this API always iterates through an empty set (all calls to
12513
**   xPhraseFirstColumn() set iCol to -1).
12514
**
12515
**   The information accessed using this API and its companion
12516
**   xPhraseFirstColumn() may also be obtained using xPhraseFirst/xPhraseNext
12517
**   (or xInst/xInstCount). The chief advantage of this API is that it is
12518
**   significantly more efficient than those alternatives when used with
12519
**   "detail=column" tables.
12520
**
12521
** xPhraseNextColumn()
12522
**   See xPhraseFirstColumn above.
12523
*/
12524
struct Fts5ExtensionApi {
12525
  int iVersion;                   /* Currently always set to 3 */
12526
12527
  void *(*xUserData)(Fts5Context*);
12528
12529
  int (*xColumnCount)(Fts5Context*);
12530
  int (*xRowCount)(Fts5Context*, sqlite3_int64 *pnRow);
12531
  int (*xColumnTotalSize)(Fts5Context*, int iCol, sqlite3_int64 *pnToken);
12532
12533
  int (*xTokenize)(Fts5Context*,
12534
    const char *pText, int nText, /* Text to tokenize */
12535
    void *pCtx,                   /* Context passed to xToken() */
12536
    int (*xToken)(void*, int, const char*, int, int, int)       /* Callback */
12537
  );
12538
12539
  int (*xPhraseCount)(Fts5Context*);
12540
  int (*xPhraseSize)(Fts5Context*, int iPhrase);
12541
12542
  int (*xInstCount)(Fts5Context*, int *pnInst);
12543
  int (*xInst)(Fts5Context*, int iIdx, int *piPhrase, int *piCol, int *piOff);
12544
12545
  sqlite3_int64 (*xRowid)(Fts5Context*);
12546
  int (*xColumnText)(Fts5Context*, int iCol, const char **pz, int *pn);
12547
  int (*xColumnSize)(Fts5Context*, int iCol, int *pnToken);
12548
12549
  int (*xQueryPhrase)(Fts5Context*, int iPhrase, void *pUserData,
12550
    int(*)(const Fts5ExtensionApi*,Fts5Context*,void*)
12551
  );
12552
  int (*xSetAuxdata)(Fts5Context*, void *pAux, void(*xDelete)(void*));
12553
  void *(*xGetAuxdata)(Fts5Context*, int bClear);
12554
12555
  int (*xPhraseFirst)(Fts5Context*, int iPhrase, Fts5PhraseIter*, int*, int*);
12556
  void (*xPhraseNext)(Fts5Context*, Fts5PhraseIter*, int *piCol, int *piOff);
12557
12558
  int (*xPhraseFirstColumn)(Fts5Context*, int iPhrase, Fts5PhraseIter*, int*);
12559
  void (*xPhraseNextColumn)(Fts5Context*, Fts5PhraseIter*, int *piCol);
12560
};
12561
12562
/*
12563
** CUSTOM AUXILIARY FUNCTIONS
12564
*************************************************************************/
12565
12566
/*************************************************************************
12567
** CUSTOM TOKENIZERS
12568
**
12569
** Applications may also register custom tokenizer types. A tokenizer
12570
** is registered by providing fts5 with a populated instance of the
12571
** following structure. All structure methods must be defined, setting
12572
** any member of the fts5_tokenizer struct to NULL leads to undefined
12573
** behaviour. The structure methods are expected to function as follows:
12574
**
12575
** xCreate:
12576
**   This function is used to allocate and initialize a tokenizer instance.
12577
**   A tokenizer instance is required to actually tokenize text.
12578
**
12579
**   The first argument passed to this function is a copy of the (void*)
12580
**   pointer provided by the application when the fts5_tokenizer object
12581
**   was registered with FTS5 (the third argument to xCreateTokenizer()).
12582
**   The second and third arguments are an array of nul-terminated strings
12583
**   containing the tokenizer arguments, if any, specified following the
12584
**   tokenizer name as part of the CREATE VIRTUAL TABLE statement used
12585
**   to create the FTS5 table.
12586
**
12587
**   The final argument is an output variable. If successful, (*ppOut)
12588
**   should be set to point to the new tokenizer handle and SQLITE_OK
12589
**   returned. If an error occurs, some value other than SQLITE_OK should
12590
**   be returned. In this case, fts5 assumes that the final value of *ppOut
12591
**   is undefined.
12592
**
12593
** xDelete:
12594
**   This function is invoked to delete a tokenizer handle previously
12595
**   allocated using xCreate(). Fts5 guarantees that this function will
12596
**   be invoked exactly once for each successful call to xCreate().
12597
**
12598
** xTokenize:
12599
**   This function is expected to tokenize the nText byte string indicated
12600
**   by argument pText. pText may or may not be nul-terminated. The first
12601
**   argument passed to this function is a pointer to an Fts5Tokenizer object
12602
**   returned by an earlier call to xCreate().
12603
**
12604
**   The second argument indicates the reason that FTS5 is requesting
12605
**   tokenization of the supplied text. This is always one of the following
12606
**   four values:
12607
**
12608
**   <ul><li> <b>FTS5_TOKENIZE_DOCUMENT</b> - A document is being inserted into
12609
**            or removed from the FTS table. The tokenizer is being invoked to
12610
**            determine the set of tokens to add to (or delete from) the
12611
**            FTS index.
12612
**
12613
**       <li> <b>FTS5_TOKENIZE_QUERY</b> - A MATCH query is being executed
12614
**            against the FTS index. The tokenizer is being called to tokenize
12615
**            a bareword or quoted string specified as part of the query.
12616
**
12617
**       <li> <b>(FTS5_TOKENIZE_QUERY | FTS5_TOKENIZE_PREFIX)</b> - Same as
12618
**            FTS5_TOKENIZE_QUERY, except that the bareword or quoted string is
12619
**            followed by a "*" character, indicating that the last token
12620
**            returned by the tokenizer will be treated as a token prefix.
12621
**
12622
**       <li> <b>FTS5_TOKENIZE_AUX</b> - The tokenizer is being invoked to
12623
**            satisfy an fts5_api.xTokenize() request made by an auxiliary
12624
**            function. Or an fts5_api.xColumnSize() request made by the same
12625
**            on a columnsize=0 database.
12626
**   </ul>
12627
**
12628
**   For each token in the input string, the supplied callback xToken() must
12629
**   be invoked. The first argument to it should be a copy of the pointer
12630
**   passed as the second argument to xTokenize(). The third and fourth
12631
**   arguments are a pointer to a buffer containing the token text, and the
12632
**   size of the token in bytes. The 4th and 5th arguments are the byte offsets
12633
**   of the first byte of and first byte immediately following the text from
12634
**   which the token is derived within the input.
12635
**
12636
**   The second argument passed to the xToken() callback ("tflags") should
12637
**   normally be set to 0. The exception is if the tokenizer supports
12638
**   synonyms. In this case see the discussion below for details.
12639
**
12640
**   FTS5 assumes the xToken() callback is invoked for each token in the
12641
**   order that they occur within the input text.
12642
**
12643
**   If an xToken() callback returns any value other than SQLITE_OK, then
12644
**   the tokenization should be abandoned and the xTokenize() method should
12645
**   immediately return a copy of the xToken() return value. Or, if the
12646
**   input buffer is exhausted, xTokenize() should return SQLITE_OK. Finally,
12647
**   if an error occurs with the xTokenize() implementation itself, it
12648
**   may abandon the tokenization and return any error code other than
12649
**   SQLITE_OK or SQLITE_DONE.
12650
**
12651
** SYNONYM SUPPORT
12652
**
12653
**   Custom tokenizers may also support synonyms. Consider a case in which a
12654
**   user wishes to query for a phrase such as "first place". Using the
12655
**   built-in tokenizers, the FTS5 query 'first + place' will match instances
12656
**   of "first place" within the document set, but not alternative forms
12657
**   such as "1st place". In some applications, it would be better to match
12658
**   all instances of "first place" or "1st place" regardless of which form
12659
**   the user specified in the MATCH query text.
12660
**
12661
**   There are several ways to approach this in FTS5:
12662
**
12663
**   <ol><li> By mapping all synonyms to a single token. In this case, using
12664
**            the above example, this means that the tokenizer returns the
12665
**            same token for inputs "first" and "1st". Say that token is in
12666
**            fact "first", so that when the user inserts the document "I won
12667
**            1st place" entries are added to the index for tokens "i", "won",
12668
**            "first" and "place". If the user then queries for '1st + place',
12669
**            the tokenizer substitutes "first" for "1st" and the query works
12670
**            as expected.
12671
**
12672
**       <li> By querying the index for all synonyms of each query term
12673
**            separately. In this case, when tokenizing query text, the
12674
**            tokenizer may provide multiple synonyms for a single term
12675
**            within the document. FTS5 then queries the index for each
12676
**            synonym individually. For example, faced with the query:
12677
**
12678
**   <codeblock>
12679
**     ... MATCH 'first place'</codeblock>
12680
**
12681
**            the tokenizer offers both "1st" and "first" as synonyms for the
12682
**            first token in the MATCH query and FTS5 effectively runs a query
12683
**            similar to:
12684
**
12685
**   <codeblock>
12686
**     ... MATCH '(first OR 1st) place'</codeblock>
12687
**
12688
**            except that, for the purposes of auxiliary functions, the query
12689
**            still appears to contain just two phrases - "(first OR 1st)"
12690
**            being treated as a single phrase.
12691
**
12692
**       <li> By adding multiple synonyms for a single term to the FTS index.
12693
**            Using this method, when tokenizing document text, the tokenizer
12694
**            provides multiple synonyms for each token. So that when a
12695
**            document such as "I won first place" is tokenized, entries are
12696
**            added to the FTS index for "i", "won", "first", "1st" and
12697
**            "place".
12698
**
12699
**            This way, even if the tokenizer does not provide synonyms
12700
**            when tokenizing query text (it should not - to do so would be
12701
**            inefficient), it doesn't matter if the user queries for
12702
**            'first + place' or '1st + place', as there are entries in the
12703
**            FTS index corresponding to both forms of the first token.
12704
**   </ol>
12705
**
12706
**   Whether it is parsing document or query text, any call to xToken that
12707
**   specifies a <i>tflags</i> argument with the FTS5_TOKEN_COLOCATED bit
12708
**   is considered to supply a synonym for the previous token. For example,
12709
**   when parsing the document "I won first place", a tokenizer that supports
12710
**   synonyms would call xToken() 5 times, as follows:
12711
**
12712
**   <codeblock>
12713
**       xToken(pCtx, 0, "i",                      1,  0,  1);
12714
**       xToken(pCtx, 0, "won",                    3,  2,  5);
12715
**       xToken(pCtx, 0, "first",                  5,  6, 11);
12716
**       xToken(pCtx, FTS5_TOKEN_COLOCATED, "1st", 3,  6, 11);
12717
**       xToken(pCtx, 0, "place",                  5, 12, 17);
12718
**</codeblock>
12719
**
12720
**   It is an error to specify the FTS5_TOKEN_COLOCATED flag the first time
12721
**   xToken() is called. Multiple synonyms may be specified for a single token
12722
**   by making multiple calls to xToken(FTS5_TOKEN_COLOCATED) in sequence.
12723
**   There is no limit to the number of synonyms that may be provided for a
12724
**   single token.
12725
**
12726
**   In many cases, method (1) above is the best approach. It does not add
12727
**   extra data to the FTS index or require FTS5 to query for multiple terms,
12728
**   so it is efficient in terms of disk space and query speed. However, it
12729
**   does not support prefix queries very well. If, as suggested above, the
12730
**   token "first" is substituted for "1st" by the tokenizer, then the query:
12731
**
12732
**   <codeblock>
12733
**     ... MATCH '1s*'</codeblock>
12734
**
12735
**   will not match documents that contain the token "1st" (as the tokenizer
12736
**   will probably not map "1s" to any prefix of "first").
12737
**
12738
**   For full prefix support, method (3) may be preferred. In this case,
12739
**   because the index contains entries for both "first" and "1st", prefix
12740
**   queries such as 'fi*' or '1s*' will match correctly. However, because
12741
**   extra entries are added to the FTS index, this method uses more space
12742
**   within the database.
12743
**
12744
**   Method (2) offers a midpoint between (1) and (3). Using this method,
12745
**   a query such as '1s*' will match documents that contain the literal
12746
**   token "1st", but not "first" (assuming the tokenizer is not able to
12747
**   provide synonyms for prefixes). However, a non-prefix query like '1st'
12748
**   will match against "1st" and "first". This method does not require
12749
**   extra disk space, as no extra entries are added to the FTS index.
12750
**   On the other hand, it may require more CPU cycles to run MATCH queries,
12751
**   as separate queries of the FTS index are required for each synonym.
12752
**
12753
**   When using methods (2) or (3), it is important that the tokenizer only
12754
**   provide synonyms when tokenizing document text (method (2)) or query
12755
**   text (method (3)), not both. Doing so will not cause any errors, but is
12756
**   inefficient.
12757
*/
12758
typedef struct Fts5Tokenizer Fts5Tokenizer;
12759
typedef struct fts5_tokenizer fts5_tokenizer;
12760
struct fts5_tokenizer {
12761
  int (*xCreate)(void*, const char **azArg, int nArg, Fts5Tokenizer **ppOut);
12762
  void (*xDelete)(Fts5Tokenizer*);
12763
  int (*xTokenize)(Fts5Tokenizer*,
12764
      void *pCtx,
12765
      int flags,            /* Mask of FTS5_TOKENIZE_* flags */
12766
      const char *pText, int nText,
12767
      int (*xToken)(
12768
        void *pCtx,         /* Copy of 2nd argument to xTokenize() */
12769
        int tflags,         /* Mask of FTS5_TOKEN_* flags */
12770
        const char *pToken, /* Pointer to buffer containing token */
12771
        int nToken,         /* Size of token in bytes */
12772
        int iStart,         /* Byte offset of token within input text */
12773
        int iEnd            /* Byte offset of end of token within input text */
12774
      )
12775
  );
12776
};
12777
12778
/* Flags that may be passed as the third argument to xTokenize() */
12779
#define FTS5_TOKENIZE_QUERY     0x0001
12780
#define FTS5_TOKENIZE_PREFIX    0x0002
12781
#define FTS5_TOKENIZE_DOCUMENT  0x0004
12782
#define FTS5_TOKENIZE_AUX       0x0008
12783
12784
/* Flags that may be passed by the tokenizer implementation back to FTS5
12785
** as the third argument to the supplied xToken callback. */
12786
#define FTS5_TOKEN_COLOCATED    0x0001      /* Same position as prev. token */
12787
12788
/*
12789
** END OF CUSTOM TOKENIZERS
12790
*************************************************************************/
12791
12792
/*************************************************************************
12793
** FTS5 EXTENSION REGISTRATION API
12794
*/
12795
typedef struct fts5_api fts5_api;
12796
struct fts5_api {
12797
  int iVersion;                   /* Currently always set to 2 */
12798
12799
  /* Create a new tokenizer */
12800
  int (*xCreateTokenizer)(
12801
    fts5_api *pApi,
12802
    const char *zName,
12803
    void *pContext,
12804
    fts5_tokenizer *pTokenizer,
12805
    void (*xDestroy)(void*)
12806
  );
12807
12808
  /* Find an existing tokenizer */
12809
  int (*xFindTokenizer)(
12810
    fts5_api *pApi,
12811
    const char *zName,
12812
    void **ppContext,
12813
    fts5_tokenizer *pTokenizer
12814
  );
12815
12816
  /* Create a new auxiliary function */
12817
  int (*xCreateFunction)(
12818
    fts5_api *pApi,
12819
    const char *zName,
12820
    void *pContext,
12821
    fts5_extension_function xFunction,
12822
    void (*xDestroy)(void*)
12823
  );
12824
};
12825
12826
/*
12827
** END OF REGISTRATION API
12828
*************************************************************************/
12829
12830
#ifdef __cplusplus
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}  /* end of the 'extern "C"' block */
12832
#endif
12833
12834
#endif /* _FTS5_H */
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/******** End of fts5.h *********/