DB_File.xs

/*

 DB_File.xs -- Perl 5 interface to Berkeley DB

 Written by Paul Marquess <pmqs@cpan.org>

 All comments/suggestions/problems are welcome

     Copyright (c) 1995-2023 Paul Marquess. All rights reserved.
     This program is free software; you can redistribute it and/or
     modify it under the same terms as Perl itself.

 Changes:
    0.1 -   Initial Release
    0.2 -   No longer bombs out if dbopen returns an error.
    0.3 -   Added some support for multiple btree compares
    1.0 -   Complete support for multiple callbacks added.
            Fixed a problem with pushing a value onto an empty list.
    1.01 -  Fixed a SunOS core dump problem.
            The return value from TIEHASH wasn't set to NULL when
            dbopen returned an error.
    1.02 -  Use ALIAS to define TIEARRAY.
            Removed some redundant commented code.
            Merged OS2 code into the main distribution.
            Allow negative subscripts with RECNO interface.
            Changed the default flags to O_CREAT|O_RDWR
    1.03 -  Added EXISTS
    1.04 -  fixed a couple of bugs in hash_cb. Patches supplied by
            Dave Hammen, hammen@gothamcity.jsc.nasa.gov
    1.05 -  Added logic to allow prefix & hash types to be specified via
            Makefile.PL
    1.06 -  Minor namespace cleanup: Localized PrintBtree.
    1.07 -  Fixed bug with RECNO, where bval wasn't defaulting to "\n".
    1.08 -  No change to DB_File.xs
    1.09 -  Default mode for dbopen changed to 0666
    1.10 -  Fixed fd method so that it still returns -1 for
            in-memory files when db 1.86 is used.
    1.11 -  No change to DB_File.xs
    1.12 -  No change to DB_File.xs
    1.13 -  Tidied up a few casts.
    1.14 -  Made it illegal to tie an associative array to a RECNO
            database and an ordinary array to a HASH or BTREE database.
    1.50 -  Make work with both DB 1.x or DB 2.x
    1.51 -  Fixed a bug in mapping 1.x O_RDONLY flag to 2.x DB_RDONLY equivalent
    1.52 -  Patch from Gisle Aas <gisle@aas.no> to suppress "use of
            undefined value" warning with db_get and db_seq.
    1.53 -  Added DB_RENUMBER to flags for recno.
    1.54 -  Fixed bug in the fd method
    1.55 -  Fix for AIX from Jarkko Hietaniemi
    1.56 -  No change to DB_File.xs
    1.57 -  added the #undef op to allow building with Threads support.
    1.58 -  Fixed a problem with the use of sv_setpvn. When the
            size is specified as 0, it does a strlen on the data.
            This was ok for DB 1.x, but isn't for DB 2.x.
    1.59 -  No change to DB_File.xs
    1.60 -  Some code tidy up
    1.61 -  added flagSet macro for DB 2.5.x
            fixed typo in O_RDONLY test.
    1.62 -  No change to DB_File.xs
    1.63 -  Fix to alllow DB 2.6.x to build.
    1.64 -  Tidied up the 1.x to 2.x flags mapping code.
            Added a patch from Mark Kettenis <kettenis@wins.uva.nl>
            to fix a flag mapping problem with O_RDONLY on the Hurd
    1.65 -  Fixed a bug in the PUSH logic.
            Added BOOT check that using 2.3.4 or greater
    1.66 -  Added DBM filter code
    1.67 -  Backed off the use of newSVpvn.
            Fixed DBM Filter code for Perl 5.004.
            Fixed a small memory leak in the filter code.
    1.68 -  fixed backward compatibility bug with R_IAFTER & R_IBEFORE
            merged in the 5.005_58 changes
    1.69 -  fixed a bug in push -- DB_APPEND wasn't working properly.
            Fixed the R_SETCURSOR bug introduced in 1.68
            Added a new Perl variable $DB_File::db_ver
    1.70 -  Initialise $DB_File::db_ver and $DB_File::db_version with
            GV_ADD|GV_ADDMULT -- bug spotted by Nick Ing-Simmons.
            Added a BOOT check to test for equivalent versions of db.h &
            libdb.a/so.
    1.71 -  Support for Berkeley DB version 3.
            Support for Berkeley DB 2/3's backward compatibility mode.
            Rewrote push
    1.72 -  No change to DB_File.xs
    1.73 -  No change to DB_File.xs
    1.74 -  A call to open needed parenthesised to stop it clashing
            with a win32 macro.
            Added Perl core patches 7703 & 7801.
    1.75 -  Fixed Perl core patch 7703.
            Added support to allow DB_File to be built with
            Berkeley DB 3.2 -- btree_compare, btree_prefix and hash_cb
            needed to be changed.
    1.76 -  No change to DB_File.xs
    1.77 -  Tidied up a few types used in calling newSVpvn.
    1.78 -  Core patch 10335, 10372, 10534, 10549, 11051 included.
    1.79 -  NEXTKEY ignores the input key.
            Added lots of casts
    1.800 - Moved backward compatibility code into ppport.h.
            Use the new constants code.
    1.801 - No change to DB_File.xs
    1.802 - No change to DB_File.xs
    1.803 - FETCH, STORE & DELETE don't map the flags parameter
            into the equivalent Berkeley DB function anymore.
    1.804 - no change.
    1.805 - recursion detection added to the callbacks
            Support for 4.1.X added.
            Filter code can now cope with read-only $_
    1.806 - recursion detection beefed up.
    1.807 - no change
    1.808 - leak fixed in ParseOpenInfo
    1.809 - no change
    1.810 - no change
    1.811 - no change
    1.812 - no change
    1.813 - no change
    1.814 - no change
    1.814 - C++ casting fixes

*/

#define PERL_NO_GET_CONTEXT
#include "EXTERN.h"
#include "perl.h"
#include "XSUB.h"

#ifdef _NOT_CORE
#  include "ppport.h"
#endif

int DB_File___unused() { return 0; }

/* Mention DB_VERSION_MAJOR_CFG, DB_VERSION_MINOR_CFG, and
   DB_VERSION_PATCH_CFG here so that Configure pulls them all in. */

/* Being the Berkeley DB we prefer the <sys/cdefs.h> (which will be
 * shortly #included by the <db.h>) __attribute__ to the possibly
 * already defined __attribute__, for example by GNUC or by Perl. */

/* #if DB_VERSION_MAJOR_CFG < 2  */
#ifndef DB_VERSION_MAJOR
#    undef __attribute__
#endif

#ifdef COMPAT185
#    include <db_185.h>
#else

/* Uncomment one of the lines below */
/* See the section "At least one secondary cursor must be specified to DB->join"
   in the README file for the circumstances where you need to uncomment one
   of the two lines below.
*/

/* #define time_t __time64_t */
/* #define time_t __time32_t */

#    include <db.h>
#endif

#ifndef PERL_UNUSED_ARG
#  define PERL_UNUSED_ARG(x) ((void)x)
#endif

/* Wall starts with 5.7.x */

#if PERL_REVISION > 5 || (PERL_REVISION == 5 && PERL_VERSION >= 7)

/* Since we dropped the gccish definition of __attribute__ we will want
 * to redefine dNOOP, however (so that dTHX continues to work).  Yes,
 * all this means that we can't do attribute checking on the DB_File,
 * boo, hiss. */
#  ifndef DB_VERSION_MAJOR

#    undef  dNOOP
#    ifdef __cplusplus
#        define dNOOP (void)0
#    else
#        define dNOOP extern int DB_File___notused()
#    endif

    /* Ditto for dXSARGS. */
#    undef  dXSARGS
#    define dXSARGS             \
    dSP; dMARK;         \
    I32 ax = mark - PL_stack_base + 1;  \
    I32 items = sp - mark

#  endif

/* avoid -Wall; DB_File xsubs never make use of `ix' setup for ALIASes */
#  undef dXSI32
#  define dXSI32 dNOOP

#endif /* Perl >= 5.7 */

#include <fcntl.h>

/* #define TRACE */

#ifdef TRACE
#    define Trace(x)        printf x
#else
#    define Trace(x)
#endif


#define DBT_clear(x)    Zero(&x, 1, DBT) ;

#ifdef DB_VERSION_MAJOR

#if DB_VERSION_MAJOR == 2
#    define BERKELEY_DB_1_OR_2
#endif

#if DB_VERSION_MAJOR > 3 || (DB_VERSION_MAJOR == 3 && DB_VERSION_MINOR >= 2)
#    define AT_LEAST_DB_3_2
#endif

#if DB_VERSION_MAJOR > 3 || (DB_VERSION_MAJOR == 3 && DB_VERSION_MINOR >= 3)
#    define AT_LEAST_DB_3_3
#endif

#if DB_VERSION_MAJOR > 4 || (DB_VERSION_MAJOR == 4 && DB_VERSION_MINOR >= 1)
#    define AT_LEAST_DB_4_1
#endif

#if DB_VERSION_MAJOR > 4 || (DB_VERSION_MAJOR == 4 && DB_VERSION_MINOR >= 3)
#    define AT_LEAST_DB_4_3
#endif

#if DB_VERSION_MAJOR >= 6
#    define AT_LEAST_DB_6_0
#endif

#ifdef AT_LEAST_DB_3_3
#   define WANT_ERROR
#endif

/* map version 2 features & constants onto their version 1 equivalent */

#ifdef DB_Prefix_t
#    undef DB_Prefix_t
#endif
#define DB_Prefix_t size_t

#ifdef DB_Hash_t
#    undef DB_Hash_t
#endif
#define DB_Hash_t   u_int32_t

/* DBTYPE stays the same */
/* HASHINFO, RECNOINFO and BTREEINFO  map to DB_INFO */
#if DB_VERSION_MAJOR == 2
    typedef DB_INFO INFO ;
#else /* DB_VERSION_MAJOR > 2 */
#    define DB_FIXEDLEN (0x8000)
#endif /* DB_VERSION_MAJOR == 2 */

/* version 2 has db_recno_t in place of recno_t */
typedef db_recno_t  recno_t;


#define R_CURSOR        DB_SET_RANGE
#define R_FIRST         DB_FIRST
#define R_IAFTER        DB_AFTER
#define R_IBEFORE       DB_BEFORE
#define R_LAST          DB_LAST
#define R_NEXT          DB_NEXT
#define R_NOOVERWRITE   DB_NOOVERWRITE
#define R_PREV          DB_PREV

#if DB_VERSION_MAJOR == 2 && DB_VERSION_MINOR < 5
#  define R_SETCURSOR   0x800000
#else
#  define R_SETCURSOR   (DB_OPFLAGS_MASK)
#endif

#define R_RECNOSYNC     0
#define R_FIXEDLEN  DB_FIXEDLEN
#define R_DUP       DB_DUP


#define db_HA_hash  h_hash
#define db_HA_ffactor   h_ffactor
#define db_HA_nelem h_nelem
#define db_HA_bsize db_pagesize
#define db_HA_cachesize db_cachesize
#define db_HA_lorder    db_lorder

#define db_BT_compare   bt_compare
#define db_BT_prefix    bt_prefix
#define db_BT_flags flags
#define db_BT_psize db_pagesize
#define db_BT_cachesize db_cachesize
#define db_BT_lorder    db_lorder
#define db_BT_maxkeypage
#define db_BT_minkeypage


#define db_RE_reclen    re_len
#define db_RE_flags flags
#define db_RE_bval  re_pad
#define db_RE_bfname    re_source
#define db_RE_psize db_pagesize
#define db_RE_cachesize db_cachesize
#define db_RE_lorder    db_lorder

#define TXN NULL,

#define do_SEQ(db, key, value, flag)    (db->cursor->c_get)(db->cursor, &key, &value, flag)


#define DBT_flags(x)    x.flags = 0
#define DB_flags(x, v)  x |= v

#if DB_VERSION_MAJOR == 2 && DB_VERSION_MINOR < 5
#    define flagSet(flags, bitmask) ((flags) & (bitmask))
#else
#    define flagSet(flags, bitmask) (((flags) & DB_OPFLAGS_MASK) == (u_int)(bitmask))
#endif

#else /* db version 1.x */

#define BERKELEY_DB_1
#define BERKELEY_DB_1_OR_2

typedef union INFO {
        HASHINFO    hash ;
        RECNOINFO   recno ;
        BTREEINFO   btree ;
      } INFO ;


#ifdef mDB_Prefix_t
#  ifdef DB_Prefix_t
#    undef DB_Prefix_t
#  endif
#  define DB_Prefix_t   mDB_Prefix_t
#endif

#ifdef mDB_Hash_t
#  ifdef DB_Hash_t
#    undef DB_Hash_t
#  endif
#  define DB_Hash_t mDB_Hash_t
#endif

#define db_HA_hash  hash.hash
#define db_HA_ffactor   hash.ffactor
#define db_HA_nelem hash.nelem
#define db_HA_bsize hash.bsize
#define db_HA_cachesize hash.cachesize
#define db_HA_lorder    hash.lorder

#define db_BT_compare   btree.compare
#define db_BT_prefix    btree.prefix
#define db_BT_flags btree.flags
#define db_BT_psize btree.psize
#define db_BT_cachesize btree.cachesize
#define db_BT_lorder    btree.lorder
#define db_BT_maxkeypage btree.maxkeypage
#define db_BT_minkeypage btree.minkeypage

#define db_RE_reclen    recno.reclen
#define db_RE_flags recno.flags
#define db_RE_bval  recno.bval
#define db_RE_bfname    recno.bfname
#define db_RE_psize recno.psize
#define db_RE_cachesize recno.cachesize
#define db_RE_lorder    recno.lorder

#define TXN

#define do_SEQ(db, key, value, flag)    (db->dbp->seq)(db->dbp, &key, &value, flag)
#define DBT_flags(x)
#define DB_flags(x, v)
#define flagSet(flags, bitmask)        ((flags) & (bitmask))

#endif /* db version 1 */



#define db_DELETE(db, key, flags)       ((db->dbp)->del)(db->dbp, TXN &key, 0)
#define db_STORE(db, key, value, flags) ((db->dbp)->put)(db->dbp, TXN &key, &value, 0)
#define db_FETCH(db, key, flags)        ((db->dbp)->get)(db->dbp, TXN &key, &value, 0)

#define db_sync(db, flags)              ((db->dbp)->sync)(db->dbp, flags)
#define db_get(db, key, value, flags)   ((db->dbp)->get)(db->dbp, TXN &key, &value, flags)

#ifdef DB_VERSION_MAJOR
#define db_DESTROY(db)                  (!db->aborted && ( db->cursor->c_close(db->cursor),\
                      (db->dbp->close)(db->dbp, 0) ))
#define db_close(db)            ((db->dbp)->close)(db->dbp, 0)
#define db_del(db, key, flags)          (flagSet(flags, R_CURSOR)                   \
                        ? ((db->cursor)->c_del)(db->cursor, 0)      \
                        : ((db->dbp)->del)(db->dbp, NULL, &key, flags) )

#else /* ! DB_VERSION_MAJOR */

#define db_DESTROY(db)                  (!db->aborted && ((db->dbp)->close)(db->dbp))
#define db_close(db)            ((db->dbp)->close)(db->dbp)
#define db_del(db, key, flags)          ((db->dbp)->del)(db->dbp, &key, flags)
#define db_put(db, key, value, flags)   ((db->dbp)->put)(db->dbp, &key, &value, flags)

#endif /* ! DB_VERSION_MAJOR */


#define db_seq(db, key, value, flags)   do_SEQ(db, key, value, flags)

typedef struct {
    DBTYPE  type ;
    DB *    dbp ;
    SV *    compare ;
    bool    in_compare ;
    SV *    prefix ;
    bool    in_prefix ;
    SV *    hash ;
    bool    in_hash ;
    bool    aborted ;
    int in_memory ;
#ifdef BERKELEY_DB_1_OR_2
    INFO    info ;
#endif
#ifdef DB_VERSION_MAJOR
    DBC *   cursor ;
#endif
    SV *    filter_fetch_key ;
    SV *    filter_store_key ;
    SV *    filter_fetch_value ;
    SV *    filter_store_value ;
    int     filtering ;

    } DB_File_type;

typedef DB_File_type * DB_File ;
typedef DBT DBTKEY ;

#define my_sv_setpvn(sv, d, s) sv_setpvn(sv, (s ? d : (const char *)""), s)

#define OutputValue(arg, name)                                              \
    { if (RETVAL == 0) {                                                    \
          SvGETMAGIC(arg) ;                                                 \
          my_sv_setpvn(arg, (const char *)name.data, name.size) ;           \
          TAINT;                                                            \
          SvTAINTED_on(arg);                                                \
          SvUTF8_off(arg);                                                  \
          DBM_ckFilter(arg, filter_fetch_value,"filter_fetch_value") ;      \
      }                                                                     \
    }

#define OutputKey(arg, name)                                          \
    { if (RETVAL == 0)                                                \
      {                                                               \
          SvGETMAGIC(arg) ;                                           \
          if (db->type != DB_RECNO) {                                 \
              my_sv_setpvn(arg, (const char *)name.data, name.size);  \
          }                                                           \
          else                                                        \
              sv_setiv(arg, (I32)*(I32*)name.data - 1);               \
          TAINT;                                                      \
          SvTAINTED_on(arg);                                          \
          SvUTF8_off(arg);                                            \
          DBM_ckFilter(arg, filter_fetch_key,"filter_fetch_key") ;    \
      }                                                               \
    }

/* Macro err_close only for use in croak_and_free */
#ifdef BERKELEY_DB_1_OR_2 /* Berkeley DB Version 1  or 2 */
#  define err_close(r)
#else
#  define err_close(r) db_close(r)
#endif

/* Macro croak_and_free only for use in ParseOpenInfo */
#define croak_and_free(x)                                             \
    do                                                                \
    {                                                                 \
        if (RETVAL->dbp) { err_close(RETVAL) ; }                      \
        Safefree(RETVAL);                                             \
        croak(x);                                                     \
    } while (0)

#define my_SvUV32(sv) ((u_int32_t)SvUV(sv))

#ifdef CAN_PROTOTYPE
extern void __getBerkeleyDBInfo(void);
#endif

/* Internal Global Data */

#define MY_CXT_KEY "DB_File::_guts" XS_VERSION

typedef struct {
    recno_t x_Value;
    recno_t x_zero;
    DB_File x_CurrentDB;
    DBTKEY  x_empty;
} my_cxt_t;

START_MY_CXT

#define Value       (MY_CXT.x_Value)
#define zero        (MY_CXT.x_zero)
#define CurrentDB   (MY_CXT.x_CurrentDB)
#define empty       (MY_CXT.x_empty)

#define ERR_BUFF "DB_File::Error"

#ifdef DB_VERSION_MAJOR

static int
#ifdef CAN_PROTOTYPE
db_put(DB_File db, DBTKEY key, DBT value, u_int flags)
#else
db_put(db, key, value, flags)
DB_File     db ;
DBTKEY      key ;
DBT         value ;
u_int       flags ;
#endif
{
    int status ;

    if (flagSet(flags, R_IAFTER) || flagSet(flags, R_IBEFORE)) {
        DBC * temp_cursor ;
        DBT l_key, l_value;

#if DB_VERSION_MAJOR == 2 && DB_VERSION_MINOR < 6
        if (((db->dbp)->cursor)(db->dbp, NULL, &temp_cursor) != 0)
#else
        if (((db->dbp)->cursor)(db->dbp, NULL, &temp_cursor, 0) != 0)
#endif
            return (-1) ;

        memset(&l_key, 0, sizeof(l_key));
        l_key.data = key.data;
        l_key.size = key.size;
        memset(&l_value, 0, sizeof(l_value));
        l_value.data = value.data;
        l_value.size = value.size;

        if ( temp_cursor->c_get(temp_cursor, &l_key, &l_value, DB_SET) != 0) {
            (void)temp_cursor->c_close(temp_cursor);
            return (-1);
        }

        status = temp_cursor->c_put(temp_cursor, &key, &value, flags);
        (void)temp_cursor->c_close(temp_cursor);

        return (status) ;
    }


    if (flagSet(flags, R_CURSOR)) {
        return ((db->cursor)->c_put)(db->cursor, &key, &value, DB_CURRENT);
    }
    if (flagSet(flags, R_SETCURSOR)) {
        if ((db->dbp)->put(db->dbp, NULL, &key, &value, 0) != 0)
            return -1 ;
        return ((db->cursor)->c_get)(db->cursor, &key, &value, DB_SET_RANGE);
    }

    return ((db->dbp)->put)(db->dbp, NULL, &key, &value, flags) ;

}

#endif /* DB_VERSION_MAJOR */

static void
tidyUp(DB_File db)
{
    db->aborted = TRUE ;
}


static int

#ifdef AT_LEAST_DB_6_0
#ifdef CAN_PROTOTYPE
btree_compare(DB * db, const DBT *key1, const DBT *key2, size_t* locp)
#else
btree_compare(db, key1, key2, locp)
DB * db ;
const DBT * key1 ;
const DBT * key2 ;
size_t* locp;
#endif /* CAN_PROTOTYPE */

#else /* Berkeley DB < 6.0 */
#ifdef AT_LEAST_DB_3_2

#ifdef CAN_PROTOTYPE
btree_compare(DB * db, const DBT *key1, const DBT *key2)
#else
btree_compare(db, key1, key2)
DB        * db ;
const DBT * key1 ;
const DBT * key2 ;
#endif /* CAN_PROTOTYPE */

#else /* Berkeley DB < 3.2 */

#ifdef CAN_PROTOTYPE
btree_compare(const DBT *key1, const DBT *key2)
#else
btree_compare(key1, key2)
const DBT * key1 ;
const DBT * key2 ;
#endif

#endif
#endif

{
#ifdef dTHX
    dTHX;
#endif
    dSP ;
    dMY_CXT ;
    void * data1, * data2 ;
    int retval ;
    int count ;

#ifdef AT_LEAST_DB_3_2
    PERL_UNUSED_ARG(db);
#endif
#ifdef AT_LEAST_DB_6_0
    PERL_UNUSED_ARG(locp);
#endif

    if (CurrentDB->in_compare) {
        tidyUp(CurrentDB);
        croak ("DB_File btree_compare: recursion detected\n") ;
    }

    data1 = (char *) key1->data ;
    data2 = (char *) key2->data ;

#ifndef newSVpvn
    /* As newSVpv will assume that the data pointer is a null terminated C
       string if the size parameter is 0, make sure that data points to an
       empty string if the length is 0
    */
    if (key1->size == 0)
        data1 = "" ;
    if (key2->size == 0)
        data2 = "" ;
#endif

    ENTER ;
    SAVETMPS;
    SAVESPTR(CurrentDB);
    CurrentDB->in_compare = FALSE;
    SAVEINT(CurrentDB->in_compare);
    CurrentDB->in_compare = TRUE;

    PUSHMARK(SP) ;
    EXTEND(SP,2) ;
    PUSHs(sv_2mortal(newSVpvn((const char*)data1,key1->size)));
    PUSHs(sv_2mortal(newSVpvn((const char*)data2,key2->size)));
    PUTBACK ;

    count = perl_call_sv(CurrentDB->compare, G_SCALAR);

    SPAGAIN ;

    if (count != 1){
        tidyUp(CurrentDB);
        croak ("DB_File btree_compare: expected 1 return value from compare sub, got %d\n", count) ;
    }

    retval = POPi ;

    PUTBACK ;
    FREETMPS ;
    LEAVE ;

    return (retval) ;

}

static DB_Prefix_t
#ifdef AT_LEAST_DB_3_2

#ifdef CAN_PROTOTYPE
btree_prefix(DB * db, const DBT *key1, const DBT *key2)
#else
btree_prefix(db, key1, key2)
Db * db ;
const DBT * key1 ;
const DBT * key2 ;
#endif

#else /* Berkeley DB < 3.2 */

#ifdef CAN_PROTOTYPE
btree_prefix(const DBT *key1, const DBT *key2)
#else
btree_prefix(key1, key2)
const DBT * key1 ;
const DBT * key2 ;
#endif

#endif
{
#ifdef dTHX
    dTHX;
#endif
    dSP ;
    dMY_CXT ;
    char * data1, * data2 ;
    int retval ;
    int count ;

#ifdef AT_LEAST_DB_3_2
    PERL_UNUSED_ARG(db);
#endif

    if (CurrentDB->in_prefix){
        tidyUp(CurrentDB);
        croak ("DB_File btree_prefix: recursion detected\n") ;
    }

    data1 = (char *) key1->data ;
    data2 = (char *) key2->data ;

#ifndef newSVpvn
    /* As newSVpv will assume that the data pointer is a null terminated C
       string if the size parameter is 0, make sure that data points to an
       empty string if the length is 0
    */
    if (key1->size == 0)
        data1 = "" ;
    if (key2->size == 0)
        data2 = "" ;
#endif

    ENTER ;
    SAVETMPS;
    SAVESPTR(CurrentDB);
    CurrentDB->in_prefix = FALSE;
    SAVEINT(CurrentDB->in_prefix);
    CurrentDB->in_prefix = TRUE;

    PUSHMARK(SP) ;
    EXTEND(SP,2) ;
    PUSHs(sv_2mortal(newSVpvn(data1,key1->size)));
    PUSHs(sv_2mortal(newSVpvn(data2,key2->size)));
    PUTBACK ;

    count = perl_call_sv(CurrentDB->prefix, G_SCALAR);

    SPAGAIN ;

    if (count != 1){
        tidyUp(CurrentDB);
        croak ("DB_File btree_prefix: expected 1 return value from prefix sub, got %d\n", count) ;
    }

    retval = POPi ;

    PUTBACK ;
    FREETMPS ;
    LEAVE ;

    return (retval) ;
}


#ifdef BERKELEY_DB_1
#    define HASH_CB_SIZE_TYPE size_t
#else
#    define HASH_CB_SIZE_TYPE u_int32_t
#endif

static DB_Hash_t
#ifdef AT_LEAST_DB_3_2

#ifdef CAN_PROTOTYPE
hash_cb(DB * db, const void *data, u_int32_t size)
#else
hash_cb(db, data, size)
DB * db ;
const void * data ;
HASH_CB_SIZE_TYPE size ;
#endif

#else /* Berkeley DB < 3.2 */

#ifdef CAN_PROTOTYPE
hash_cb(const void *data, HASH_CB_SIZE_TYPE size)
#else
hash_cb(data, size)
const void * data ;
HASH_CB_SIZE_TYPE size ;
#endif

#endif
{
#ifdef dTHX
    dTHX;
#endif
    dSP ;
    dMY_CXT;
    int retval = 0;
    int count ;

#ifdef AT_LEAST_DB_3_2
    PERL_UNUSED_ARG(db);
#endif

    if (CurrentDB->in_hash){
        tidyUp(CurrentDB);
        croak ("DB_File hash callback: recursion detected\n") ;
    }

#ifndef newSVpvn
    if (size == 0)
        data = "" ;
#endif

     /* DGH - Next two lines added to fix corrupted stack problem */
    ENTER ;
    SAVETMPS;
    SAVESPTR(CurrentDB);
    CurrentDB->in_hash = FALSE;
    SAVEINT(CurrentDB->in_hash);
    CurrentDB->in_hash = TRUE;

    PUSHMARK(SP) ;


    XPUSHs(sv_2mortal(newSVpvn((char*)data,size)));
    PUTBACK ;

    count = perl_call_sv(CurrentDB->hash, G_SCALAR);

    SPAGAIN ;

    if (count != 1){
        tidyUp(CurrentDB);
        croak ("DB_File hash_cb: expected 1 return value from hash sub, got %d\n", count) ;
    }

    retval = POPi ;

    PUTBACK ;
    FREETMPS ;
    LEAVE ;

    return (retval) ;
}

#ifdef WANT_ERROR

static void
#ifdef AT_LEAST_DB_4_3
db_errcall_cb(const DB_ENV* dbenv, const char * db_errpfx, const char * buffer)
#else
db_errcall_cb(const char * db_errpfx, char * buffer)
#endif
{
#ifdef dTHX
    dTHX;
#endif
    SV * sv = perl_get_sv(ERR_BUFF, FALSE) ;
#ifdef AT_LEAST_DB_4_3
    PERL_UNUSED_ARG(dbenv);
#endif
    if (sv) {
        if (db_errpfx)
            sv_setpvf(sv, "%s: %s", db_errpfx, buffer) ;
        else
            sv_setpv(sv, buffer) ;
    }
}
#endif

#if defined(TRACE) && defined(BERKELEY_DB_1_OR_2)

static void
#ifdef CAN_PROTOTYPE
PrintHash(INFO *hash)
#else
PrintHash(hash)
INFO * hash ;
#endif
{
    printf ("HASH Info\n") ;
    printf ("  hash      = %s\n",
            (hash->db_HA_hash != NULL ? "redefined" : "default")) ;
    printf ("  bsize     = %d\n", hash->db_HA_bsize) ;
    printf ("  ffactor   = %d\n", hash->db_HA_ffactor) ;
    printf ("  nelem     = %d\n", hash->db_HA_nelem) ;
    printf ("  cachesize = %d\n", hash->db_HA_cachesize) ;
    printf ("  lorder    = %d\n", hash->db_HA_lorder) ;

}

static void
#ifdef CAN_PROTOTYPE
PrintRecno(INFO *recno)
#else
PrintRecno(recno)
INFO * recno ;
#endif
{
    printf ("RECNO Info\n") ;
    printf ("  flags     = %d\n", recno->db_RE_flags) ;
    printf ("  cachesize = %d\n", recno->db_RE_cachesize) ;
    printf ("  psize     = %d\n", recno->db_RE_psize) ;
    printf ("  lorder    = %d\n", recno->db_RE_lorder) ;
    printf ("  reclen    = %lu\n", (unsigned long)recno->db_RE_reclen) ;
    printf ("  bval      = %d 0x%x\n", recno->db_RE_bval, recno->db_RE_bval) ;
    printf ("  bfname    = %d [%s]\n", recno->db_RE_bfname, recno->db_RE_bfname) ;
}

static void
#ifdef CAN_PROTOTYPE
PrintBtree(INFO *btree)
#else
PrintBtree(btree)
INFO * btree ;
#endif
{
    printf ("BTREE Info\n") ;
    printf ("  compare    = %s\n",
            (btree->db_BT_compare ? "redefined" : "default")) ;
    printf ("  prefix     = %s\n",
            (btree->db_BT_prefix ? "redefined" : "default")) ;
    printf ("  flags      = %d\n", btree->db_BT_flags) ;
    printf ("  cachesize  = %d\n", btree->db_BT_cachesize) ;
    printf ("  psize      = %d\n", btree->db_BT_psize) ;
#ifndef DB_VERSION_MAJOR
    printf ("  maxkeypage = %d\n", btree->db_BT_maxkeypage) ;
    printf ("  minkeypage = %d\n", btree->db_BT_minkeypage) ;
#endif
    printf ("  lorder     = %d\n", btree->db_BT_lorder) ;
}

#else

#define PrintRecno(recno)
#define PrintHash(hash)
#define PrintBtree(btree)

#endif /* TRACE */


static I32
#ifdef CAN_PROTOTYPE
GetArrayLength(pTHX_ DB_File db)
#else
GetArrayLength(db)
DB_File db ;
#endif
{
    DBT     key ;
    DBT     value ;
    int     RETVAL ;

    DBT_clear(key) ;
    DBT_clear(value) ;
    RETVAL = do_SEQ(db, key, value, R_LAST) ;
    if (RETVAL == 0)
        RETVAL = *(I32 *)key.data ;
    else /* No key means empty file */
        RETVAL = 0 ;

    return ((I32)RETVAL) ;
}

static recno_t
#ifdef CAN_PROTOTYPE
GetRecnoKey(pTHX_ DB_File db, I32 value)
#else
GetRecnoKey(db, value)
DB_File  db ;
I32      value ;
#endif
{
    if (value < 0) {
        /* Get the length of the array */
        I32 length = GetArrayLength(aTHX_ db) ;

        /* check for attempt to write before start of array */
        if (length + value + 1 <= 0) {
            tidyUp(db);
            croak("Modification of non-creatable array value attempted, subscript %ld", (long)value) ;
        }

        value = length + value + 1 ;
    }
    else
        ++ value ;

    return value ;
}


static DB_File
#ifdef CAN_PROTOTYPE
ParseOpenInfo(pTHX_ int isHASH, char *name, int flags, int mode, SV *sv)
#else
ParseOpenInfo(isHASH, name, flags, mode, sv)
int    isHASH ;
char * name ;
int    flags ;
int    mode ;
SV *   sv ;
#endif
{

#ifdef BERKELEY_DB_1_OR_2 /* Berkeley DB Version 1  or 2 */

    SV **   svp;
    HV *    action ;
    DB_File RETVAL = (DB_File)safemalloc(sizeof(DB_File_type)) ;
    void *  openinfo = NULL ;
    INFO    * info  = &RETVAL->info ;
    STRLEN  n_a;
    dMY_CXT;

#ifdef TRACE
    printf("In ParseOpenInfo name=[%s] flags=[%d] mode=[%d] SV NULL=[%d]\n",
            name, flags, mode, sv == NULL) ;
#endif
    Zero(RETVAL, 1, DB_File_type) ;

    /* Default to HASH */
    RETVAL->filtering = 0 ;
    RETVAL->filter_fetch_key = RETVAL->filter_store_key =
    RETVAL->filter_fetch_value = RETVAL->filter_store_value =
    RETVAL->hash = RETVAL->compare = RETVAL->prefix = NULL ;
    RETVAL->type = DB_HASH ;

     /* DGH - Next line added to avoid SEGV on existing hash DB */
    CurrentDB = RETVAL;

    /* fd for 1.86 hash in memory files doesn't return -1 like 1.85 */
    RETVAL->in_memory = (name == NULL) ;

    if (sv)
    {
        if (! SvROK(sv) )
            croak_and_free("type parameter is not a reference") ;

        svp  = hv_fetch( (HV*)SvRV(sv), "GOT", 3, FALSE) ;
        if (svp && SvOK(*svp))
            action  = (HV*) SvRV(*svp) ;
        else
            croak_and_free("internal error") ;

        if (sv_isa(sv, "DB_File::HASHINFO"))
        {

            if (!isHASH)
                croak_and_free("DB_File can only tie an associative array to a DB_HASH database") ;

            RETVAL->type = DB_HASH ;
            openinfo = (void*)info ;

            svp = hv_fetch(action, "hash", 4, FALSE);

            if (svp && SvOK(*svp))
            {
                info->db_HA_hash = hash_cb ;
                RETVAL->hash = newSVsv(*svp) ;
            }
            else
                info->db_HA_hash = NULL ;

            svp = hv_fetch(action, "ffactor", 7, FALSE);
            info->db_HA_ffactor = svp ? SvIV(*svp) : 0;

            svp = hv_fetch(action, "nelem", 5, FALSE);
            info->db_HA_nelem = svp ? SvIV(*svp) : 0;

            svp = hv_fetch(action, "bsize", 5, FALSE);
            info->db_HA_bsize = svp ? SvIV(*svp) : 0;

            svp = hv_fetch(action, "cachesize", 9, FALSE);
            info->db_HA_cachesize = svp ? SvIV(*svp) : 0;

            svp = hv_fetch(action, "lorder", 6, FALSE);
            info->db_HA_lorder = svp ? SvIV(*svp) : 0;

            PrintHash(info) ;
        }
        else if (sv_isa(sv, "DB_File::BTREEINFO"))
        {
            if (!isHASH)
                croak_and_free("DB_File can only tie an associative array to a DB_BTREE database");

            RETVAL->type = DB_BTREE ;
            openinfo = (void*)info ;

            svp = hv_fetch(action, "compare", 7, FALSE);
            if (svp && SvOK(*svp))
            {
                info->db_BT_compare = btree_compare ;
                RETVAL->compare = newSVsv(*svp) ;
            }
            else
                info->db_BT_compare = NULL ;

            svp = hv_fetch(action, "prefix", 6, FALSE);
            if (svp && SvOK(*svp))
            {
                info->db_BT_prefix = btree_prefix ;
                RETVAL->prefix = newSVsv(*svp) ;
            }
            else
                info->db_BT_prefix = NULL ;

            svp = hv_fetch(action, "flags", 5, FALSE);
            info->db_BT_flags = svp ? SvIV(*svp) : 0;

            svp = hv_fetch(action, "cachesize", 9, FALSE);
            info->db_BT_cachesize = svp ? SvIV(*svp) : 0;

#ifndef DB_VERSION_MAJOR
            svp = hv_fetch(action, "minkeypage", 10, FALSE);
            info->btree.minkeypage = svp ? SvIV(*svp) : 0;

            svp = hv_fetch(action, "maxkeypage", 10, FALSE);
            info->btree.maxkeypage = svp ? SvIV(*svp) : 0;
#endif

            svp = hv_fetch(action, "psize", 5, FALSE);
            info->db_BT_psize = svp ? SvIV(*svp) : 0;

            svp = hv_fetch(action, "lorder", 6, FALSE);
            info->db_BT_lorder = svp ? SvIV(*svp) : 0;

            PrintBtree(info) ;

        }
        else if (sv_isa(sv, "DB_File::RECNOINFO"))
        {
            if (isHASH)
                croak_and_free("DB_File can only tie an array to a DB_RECNO database");

            RETVAL->type = DB_RECNO ;
            openinfo = (void *)info ;

            info->db_RE_flags = 0 ;

            svp = hv_fetch(action, "flags", 5, FALSE);
            info->db_RE_flags = (u_long) (svp ? SvIV(*svp) : 0);

            svp = hv_fetch(action, "reclen", 6, FALSE);
            info->db_RE_reclen = (size_t) (svp ? SvIV(*svp) : 0);

            svp = hv_fetch(action, "cachesize", 9, FALSE);
            info->db_RE_cachesize = (u_int) (svp ? SvIV(*svp) : 0);

            svp = hv_fetch(action, "psize", 5, FALSE);
            info->db_RE_psize = (u_int) (svp ? SvIV(*svp) : 0);

            svp = hv_fetch(action, "lorder", 6, FALSE);
            info->db_RE_lorder = (int) (svp ? SvIV(*svp) : 0);

#ifdef DB_VERSION_MAJOR
            info->re_source = name ;
            name = NULL ;
#endif
            svp = hv_fetch(action, "bfname", 6, FALSE);
            if (svp && SvOK(*svp)) {
                char * ptr = SvPV(*svp,n_a) ;
#ifdef DB_VERSION_MAJOR
                name = (char*) n_a ? ptr : NULL ;
#else
                info->db_RE_bfname = (char*) (n_a ? ptr : NULL) ;
#endif
            }
            else
#ifdef DB_VERSION_MAJOR
               name = NULL ;
#else
               info->db_RE_bfname = NULL ;
#endif

            svp = hv_fetch(action, "bval", 4, FALSE);
#ifdef DB_VERSION_MAJOR
            if (svp && SvOK(*svp))
            {
                int value ;
                if (SvPOK(*svp))
                    value = (int)*SvPV(*svp, n_a) ;
                else
                    value = SvIV(*svp) ;

                if (info->flags & DB_FIXEDLEN) {
                    info->re_pad = value ;
                    info->flags |= DB_PAD ;
                }
                else {
                    info->re_delim = value ;
                    info->flags |= DB_DELIMITER ;
                }

            }
#else
            if (svp && SvOK(*svp))
            {
                if (SvPOK(*svp))
                    info->db_RE_bval = (u_char)*SvPV(*svp, n_a) ;
                else
                    info->db_RE_bval = (u_char)(unsigned long) SvIV(*svp) ;
                DB_flags(info->flags, DB_DELIMITER) ;

            }
            else
            {
                if (info->db_RE_flags & R_FIXEDLEN)
                    info->db_RE_bval = (u_char) ' ' ;
                else
                    info->db_RE_bval = (u_char) '\n' ;
                DB_flags(info->flags, DB_DELIMITER) ;
            }
#endif

#ifdef DB_RENUMBER
            info->flags |= DB_RENUMBER ;
#endif

            PrintRecno(info) ;
        }
        else
            croak_and_free("type is not of type DB_File::HASHINFO, DB_File::BTREEINFO or DB_File::RECNOINFO");
    }


    /* OS2 Specific Code */
#ifdef OS2
#ifdef __EMX__
    flags |= O_BINARY;
#endif /* __EMX__ */
#endif /* OS2 */

#ifdef DB_VERSION_MAJOR

    {
        int     Flags = 0 ;
        int     status ;

        /* Map 1.x flags to 2.x flags */
        if ((flags & O_CREAT) == O_CREAT)
            Flags |= DB_CREATE ;

#if O_RDONLY == 0
        if (flags == O_RDONLY)
#else
        if ((flags & O_RDONLY) == O_RDONLY && (flags & O_RDWR) != O_RDWR)
#endif
            Flags |= DB_RDONLY ;

#ifdef O_TRUNC
        if ((flags & O_TRUNC) == O_TRUNC)
            Flags |= DB_TRUNCATE ;
#endif

        status = db_open(name, RETVAL->type, Flags, mode, NULL, (DB_INFO*)openinfo, &RETVAL->dbp) ;
        if (status == 0)
#if DB_VERSION_MAJOR == 2 && DB_VERSION_MINOR < 6
            status = (RETVAL->dbp->cursor)(RETVAL->dbp, NULL, &RETVAL->cursor) ;
#else
            status = (RETVAL->dbp->cursor)(RETVAL->dbp, NULL, &RETVAL->cursor, 0) ;
#endif

        if (status)
             RETVAL->dbp = NULL ;
    }
#else

#if defined(DB_LIBRARY_COMPATIBILITY_API) && DB_VERSION_MAJOR > 2
    RETVAL->dbp = __db185_open(name, flags, mode, RETVAL->type, openinfo) ;
#else
    RETVAL->dbp = dbopen(name, flags, mode, RETVAL->type, openinfo) ;
#endif /* DB_LIBRARY_COMPATIBILITY_API */

#endif

    return (RETVAL) ;

#else /* Berkeley DB Version > 2 */

    SV **   svp;
    HV *    action ;
    DB_File RETVAL = (DB_File)safemalloc(sizeof(DB_File_type)) ;
    DB *    dbp ;
    STRLEN  n_a;
    int     status ;
    dMY_CXT;

    Trace(("In ParseOpenInfo name=[%s] flags=[%d] mode=[%d] SV NULL=[%d]\n",\
            name, flags, mode, sv == NULL)) ;
    Zero(RETVAL, 1, DB_File_type) ;

    /* Default to HASH */
    RETVAL->filtering = 0 ;
    RETVAL->filter_fetch_key = RETVAL->filter_store_key =
    RETVAL->filter_fetch_value = RETVAL->filter_store_value =
    RETVAL->hash = RETVAL->compare = RETVAL->prefix = NULL ;
    RETVAL->type = DB_HASH ;

     /* DGH - Next line added to avoid SEGV on existing hash DB */
    CurrentDB = RETVAL;

    /* fd for 1.86 hash in memory files doesn't return -1 like 1.85 */
    RETVAL->in_memory = (name == NULL) ;

    status = db_create(&RETVAL->dbp, NULL,0) ;
    Trace(("db_create returned %d %s\n", status, db_strerror(status))) ;
    if (status) {
        RETVAL->dbp = NULL ;
        return (RETVAL) ;
    }
    dbp = RETVAL->dbp ;

#ifdef WANT_ERROR
    RETVAL->dbp->set_errcall(RETVAL->dbp, db_errcall_cb) ;
#endif
    if (sv)
    {
        if (! SvROK(sv) )
            croak_and_free("type parameter is not a reference") ;

        svp  = hv_fetch( (HV*)SvRV(sv), "GOT", 3, FALSE) ;
        if (svp && SvOK(*svp))
            action  = (HV*) SvRV(*svp) ;
        else
            croak_and_free("internal error") ;

        if (sv_isa(sv, "DB_File::HASHINFO"))
        {

            if (!isHASH)
                croak_and_free("DB_File can only tie an associative array to a DB_HASH database") ;

            RETVAL->type = DB_HASH ;

            svp = hv_fetch(action, "hash", 4, FALSE);

            if (svp && SvOK(*svp))
            {
                (void)dbp->set_h_hash(dbp, hash_cb) ;
                RETVAL->hash = newSVsv(*svp) ;
            }

           svp = hv_fetch(action, "ffactor", 7, FALSE);
           if (svp)
               (void)dbp->set_h_ffactor(dbp, my_SvUV32(*svp)) ;

           svp = hv_fetch(action, "nelem", 5, FALSE);
           if (svp)
               (void)dbp->set_h_nelem(dbp, my_SvUV32(*svp)) ;

           svp = hv_fetch(action, "bsize", 5, FALSE);
           if (svp)
               (void)dbp->set_pagesize(dbp, my_SvUV32(*svp));

           svp = hv_fetch(action, "cachesize", 9, FALSE);
           if (svp)
               (void)dbp->set_cachesize(dbp, 0, my_SvUV32(*svp), 0) ;

           svp = hv_fetch(action, "lorder", 6, FALSE);
           if (svp)
               (void)dbp->set_lorder(dbp, (int)SvIV(*svp)) ;

           PrintHash(info) ;
        }
        else if (sv_isa(sv, "DB_File::BTREEINFO"))
        {
            if (!isHASH)
                croak_and_free("DB_File can only tie an associative array to a DB_BTREE database");

            RETVAL->type = DB_BTREE ;

            svp = hv_fetch(action, "compare", 7, FALSE);
            if (svp && SvOK(*svp))
            {
                (void)dbp->set_bt_compare(dbp, btree_compare) ;
                RETVAL->compare = newSVsv(*svp) ;
            }

            svp = hv_fetch(action, "prefix", 6, FALSE);
            if (svp && SvOK(*svp))
            {
                (void)dbp->set_bt_prefix(dbp, btree_prefix) ;
                RETVAL->prefix = newSVsv(*svp) ;
            }

           svp = hv_fetch(action, "flags", 5, FALSE);
           if (svp)
               (void)dbp->set_flags(dbp, my_SvUV32(*svp)) ;

           svp = hv_fetch(action, "cachesize", 9, FALSE);
           if (svp)
               (void)dbp->set_cachesize(dbp, 0, my_SvUV32(*svp), 0) ;

           svp = hv_fetch(action, "psize", 5, FALSE);
           if (svp)
               (void)dbp->set_pagesize(dbp, my_SvUV32(*svp)) ;

           svp = hv_fetch(action, "lorder", 6, FALSE);
           if (svp)
               (void)dbp->set_lorder(dbp, (int)SvIV(*svp)) ;

           PrintBtree(info) ;

        }
        else if (sv_isa(sv, "DB_File::RECNOINFO"))
        {
            int fixed = FALSE ;

            if (isHASH)
                croak_and_free("DB_File can only tie an array to a DB_RECNO database");

            RETVAL->type = DB_RECNO ;

            svp = hv_fetch(action, "flags", 5, FALSE);
            if (svp) {
                int flags = SvIV(*svp) ;
                /* remove FIXDLEN, if present */
                if (flags & DB_FIXEDLEN) {
                    fixed = TRUE ;
                    flags &= ~DB_FIXEDLEN ;
                }
            }

            svp = hv_fetch(action, "cachesize", 9, FALSE);
            if (svp) {
                status = dbp->set_cachesize(dbp, 0, my_SvUV32(*svp), 0) ;
            }

            svp = hv_fetch(action, "psize", 5, FALSE);
            if (svp) {
                status = dbp->set_pagesize(dbp, my_SvUV32(*svp)) ;
            }

            svp = hv_fetch(action, "lorder", 6, FALSE);
            if (svp) {
                status = dbp->set_lorder(dbp, (int)SvIV(*svp)) ;
            }

            svp = hv_fetch(action, "bval", 4, FALSE);
            if (svp && SvOK(*svp))
            {
                int value ;
                if (SvPOK(*svp))
                    value = (int)*SvPV(*svp, n_a) ;
                else
                    value = (int)SvIV(*svp) ;

                if (fixed) {
                    (void)dbp->set_re_pad(dbp, value) ;
                }
                else {
                    (void)dbp->set_re_delim(dbp, value) ;
                }

            }

            if (fixed) {
                svp = hv_fetch(action, "reclen", 6, FALSE);
                if (svp) {
                    u_int32_t len =  my_SvUV32(*svp) ;
                    (void)dbp->set_re_len(dbp, len) ;
                }
            }

            if (name != NULL) {
                (void)dbp->set_re_source(dbp, name) ;
                name = NULL ;
            }

            svp = hv_fetch(action, "bfname", 6, FALSE);
            if (svp && SvOK(*svp)) {
                char * ptr = SvPV(*svp,n_a) ;
                name = (char*) n_a ? ptr : NULL ;
            }
            else
                name = NULL ;


            (void)dbp->set_flags(dbp, (u_int32_t)DB_RENUMBER) ;

            if (flags){
                (void)dbp->set_flags(dbp, (u_int32_t)flags) ;
            }
            PrintRecno(info) ;
        }
        else
            croak_and_free("type is not of type DB_File::HASHINFO, DB_File::BTREEINFO or DB_File::RECNOINFO");
    }

    {
        u_int32_t   Flags = 0 ;
        int     status ;

        /* Map 1.x flags to 3.x flags */
        if ((flags & O_CREAT) == O_CREAT)
            Flags |= DB_CREATE ;

#if O_RDONLY == 0
        if (flags == O_RDONLY)
#else
        if ((flags & O_RDONLY) == O_RDONLY && (flags & O_RDWR) != O_RDWR)
#endif
            Flags |= DB_RDONLY ;

#ifdef O_TRUNC
        if ((flags & O_TRUNC) == O_TRUNC)
            Flags |= DB_TRUNCATE ;
#endif

#ifdef AT_LEAST_DB_4_4
        /* need this for recno */
        if ((flags & O_TRUNC) == O_TRUNC)
            Flags |= DB_CREATE ;
#endif

#ifdef AT_LEAST_DB_4_1
        status = (RETVAL->dbp->open)(RETVAL->dbp, NULL, name, NULL, RETVAL->type,
                    Flags, mode) ;
#else
        status = (RETVAL->dbp->open)(RETVAL->dbp, name, NULL, RETVAL->type,
                    Flags, mode) ;
#endif
        Trace(("open returned %d %s\n", status, db_strerror(status))) ;

        if (status == 0) {

            status = (RETVAL->dbp->cursor)(RETVAL->dbp, NULL, &RETVAL->cursor, 0) ;
            Trace(("cursor returned %d %s\n", status, db_strerror(status))) ;
        }

        if (status)
        {
            db_close(RETVAL); /* close **dbp handle to prevent mem.leak */
            RETVAL->dbp = NULL ;
        }
    }

    return (RETVAL) ;

#endif /* Berkeley DB Version > 2 */

} /* ParseOpenInfo */


#include "constants.h"

MODULE = DB_File    PACKAGE = DB_File   PREFIX = db_

INCLUDE: constants.xs

BOOT:
  {
#ifdef dTHX
    dTHX;
#endif
#ifdef WANT_ERROR
    SV * sv_err = perl_get_sv(ERR_BUFF, GV_ADD|GV_ADDMULTI) ;
#endif
    MY_CXT_INIT;
#ifdef WANT_ERROR
    PERL_UNUSED_VAR(sv_err); /* huh? we just retrieved it... */
#endif
    __getBerkeleyDBInfo() ;

    DBT_clear(empty) ;
    empty.data = &zero ;
    empty.size =  sizeof(recno_t) ;
  }



DB_File
db_DoTie_(isHASH, dbtype, name=undef, flags=O_CREAT|O_RDWR, mode=0666, type=DB_HASH)
    int     isHASH
    char *      dbtype
    int     flags
    int     mode
    CODE:
    {
        char *  name = (char *) NULL ;
        SV *    sv = (SV *) NULL ;
        STRLEN  n_a;
        Trace(("In db_DoTie_\n"));

        if (items >= 3 && SvOK(ST(2)))
            name = (char*) SvPV(ST(2), n_a) ;

        if (items == 6)
            sv = ST(5) ;

        RETVAL = ParseOpenInfo(aTHX_ isHASH, name, flags, mode, sv) ;
        Trace(("db_DoTie_ %p\n", RETVAL));
        if (RETVAL->dbp == NULL) {
            Safefree(RETVAL);
            RETVAL = NULL ;
        }
    }
    OUTPUT:
        RETVAL

int
db_DESTROY(db)
    DB_File     db
    PREINIT:
      dMY_CXT;
    INIT:
      CurrentDB = db ;
      Trace(("DESTROY %p\n", db));
    CLEANUP:
      Trace(("DESTROY %p done\n", db));
      if (db->hash)
        SvREFCNT_dec(db->hash) ;
      if (db->compare)
        SvREFCNT_dec(db->compare) ;
      if (db->prefix)
        SvREFCNT_dec(db->prefix) ;
      if (db->filter_fetch_key)
        SvREFCNT_dec(db->filter_fetch_key) ;
      if (db->filter_store_key)
        SvREFCNT_dec(db->filter_store_key) ;
      if (db->filter_fetch_value)
        SvREFCNT_dec(db->filter_fetch_value) ;
      if (db->filter_store_value)
        SvREFCNT_dec(db->filter_store_value) ;
      safefree(db) ;
#ifdef DB_VERSION_MAJOR
      if (RETVAL > 0)
        RETVAL = -1 ;
#endif


int
db_DELETE(db, key, flags=0)
    DB_File     db
    DBTKEY      key
    u_int       flags
    PREINIT:
      dMY_CXT;
    INIT:
      (void)flags;
      CurrentDB = db ;


int
db_EXISTS(db, key)
    DB_File     db
    DBTKEY      key
    PREINIT:
      dMY_CXT;
    CODE:
    {
      DBT       value ;

      DBT_clear(value) ;
      CurrentDB = db ;
      RETVAL = (((db->dbp)->get)(db->dbp, TXN &key, &value, 0) == 0) ;
    }
    OUTPUT:
      RETVAL

void
db_FETCH(db, key, flags=0)
    DB_File     db
    DBTKEY      key
    u_int       flags
    PREINIT:
      dMY_CXT ;
      int RETVAL ;
    CODE:
    {
        DBT     value ;

        DBT_clear(value) ;
        CurrentDB = db ;
        RETVAL = db_get(db, key, value, flags) ;
        ST(0) = sv_newmortal();
        OutputValue(ST(0), value)
    }

int
db_STORE(db, key, value, flags=0)
    DB_File     db
    DBTKEY      key
    DBT     value
    u_int       flags
    PREINIT:
      dMY_CXT;
    INIT:
      (void)flags;
      CurrentDB = db ;


void
db_FIRSTKEY(db)
    DB_File     db
    PREINIT:
      dMY_CXT ;
      int RETVAL ;
    CODE:
    {
        DBTKEY  key ;
        DBT     value ;

        DBT_clear(key) ;
        DBT_clear(value) ;
        CurrentDB = db ;
        RETVAL = do_SEQ(db, key, value, R_FIRST) ;
        ST(0) = sv_newmortal();
        OutputKey(ST(0), key) ;
    }

void
db_NEXTKEY(db, key)
    DB_File     db
    DBTKEY      key = NO_INIT
    PREINIT:
      dMY_CXT ;
      int RETVAL ;
    CODE:
    {
        DBT     value ;

        DBT_clear(key) ;
        DBT_clear(value) ;
        CurrentDB = db ;
        RETVAL = do_SEQ(db, key, value, R_NEXT) ;
        ST(0) = sv_newmortal();
        OutputKey(ST(0), key) ;
    }

#
# These would be nice for RECNO
#

int
unshift(db, ...)
    DB_File     db
    ALIAS:      UNSHIFT = 1
    PREINIT:
      dMY_CXT;
    CODE:
    {
        DBTKEY  key ;
        DBT     value ;
        int     i ;
        int     One ;
        STRLEN  n_a;

        DBT_clear(key) ;
        DBT_clear(value) ;
        CurrentDB = db ;
#ifdef DB_VERSION_MAJOR
        /* get the first value */
        RETVAL = do_SEQ(db, key, value, DB_FIRST) ;
        RETVAL = 0 ;
#else
        RETVAL = -1 ;
#endif
        for (i = items-1 ; i > 0 ; --i)
        {
            DBM_ckFilter(ST(i), filter_store_value, "filter_store_value");
            value.data = SvPVbyte(ST(i), n_a) ;
            value.size = n_a ;
            One = 1 ;
            key.data = &One ;
            key.size = sizeof(int) ;
#ifdef DB_VERSION_MAJOR
            RETVAL = (db->cursor->c_put)(db->cursor, &key, &value, DB_BEFORE) ;
#else
            RETVAL = (db->dbp->put)(db->dbp, &key, &value, R_IBEFORE) ;
#endif
            if (RETVAL != 0)
                break;
        }
    }
    OUTPUT:
        RETVAL

void
pop(db)
    DB_File     db
    PREINIT:
      dMY_CXT;
    ALIAS:      POP = 1
    PREINIT:
      I32 RETVAL;
    CODE:
    {
        DBTKEY  key ;
        DBT     value ;

        DBT_clear(key) ;
        DBT_clear(value) ;
        CurrentDB = db ;

        /* First get the final value */
        RETVAL = do_SEQ(db, key, value, R_LAST) ;
        ST(0) = sv_newmortal();
        /* Now delete it */
        if (RETVAL == 0)
        {
            /* the call to del will trash value, so take a copy now */
            OutputValue(ST(0), value) ;
            RETVAL = db_del(db, key, R_CURSOR) ;
            if (RETVAL != 0)
                sv_setsv(ST(0), &PL_sv_undef);
        }
    }

void
shift(db)
    DB_File     db
    PREINIT:
      dMY_CXT;
    ALIAS:      SHIFT = 1
    PREINIT:
      I32 RETVAL;
    CODE:
    {
        DBT     value ;
        DBTKEY  key ;

        DBT_clear(key) ;
        DBT_clear(value) ;
        CurrentDB = db ;
        /* get the first value */
        RETVAL = do_SEQ(db, key, value, R_FIRST) ;
        ST(0) = sv_newmortal();
        /* Now delete it */
        if (RETVAL == 0)
        {
            /* the call to del will trash value, so take a copy now */
            OutputValue(ST(0), value) ;
            RETVAL = db_del(db, key, R_CURSOR) ;
            if (RETVAL != 0)
                sv_setsv (ST(0), &PL_sv_undef) ;
        }
    }


I32
push(db, ...)
    DB_File     db
    PREINIT:
      dMY_CXT;
    ALIAS:      PUSH = 1
    CODE:
    {
        DBTKEY  key ;
        DBT     value ;
        DB *    Db = db->dbp ;
        int     i ;
        STRLEN  n_a;
        int     keyval ;

        DBT_flags(key) ;
        DBT_flags(value) ;
        CurrentDB = db ;
        /* Set the Cursor to the Last element */
        RETVAL = do_SEQ(db, key, value, R_LAST) ;
#ifndef DB_VERSION_MAJOR
        if (RETVAL >= 0)
#endif
        {
            if (RETVAL == 0)
                keyval = *(int*)key.data ;
            else
                keyval = 0 ;
            for (i = 1 ; i < items ; ++i)
            {
                DBM_ckFilter(ST(i), filter_store_value, "filter_store_value");
                value.data = SvPVbyte(ST(i), n_a) ;
                value.size = n_a ;
                ++ keyval ;
                key.data = &keyval ;
                key.size = sizeof(int) ;
                RETVAL = (Db->put)(Db, TXN &key, &value, 0) ;
                if (RETVAL != 0)
                    break;
            }
        }
    }
    OUTPUT:
        RETVAL

I32
length(db)
    DB_File     db
    PREINIT:
      dMY_CXT;
    ALIAS:      FETCHSIZE = 1
    CODE:
        CurrentDB = db ;
        RETVAL = GetArrayLength(aTHX_ db) ;
    OUTPUT:
        RETVAL


#
# Now provide an interface to the rest of the DB functionality
#

int
db_del(db, key, flags=0)
    DB_File     db
    DBTKEY      key
    u_int       flags
    PREINIT:
      dMY_CXT;
    CODE:
      CurrentDB = db ;
      RETVAL = db_del(db, key, flags) ;
#ifdef DB_VERSION_MAJOR
      if (RETVAL > 0)
        RETVAL = -1 ;
      else if (RETVAL == DB_NOTFOUND)
        RETVAL = 1 ;
#endif
    OUTPUT:
      RETVAL


int
db_get(db, key, value, flags=0)
    DB_File     db
    DBTKEY      key
    DBT     value = NO_INIT
    u_int       flags
    PREINIT:
      dMY_CXT;
    CODE:
      CurrentDB = db ;
      DBT_clear(value) ;
      RETVAL = db_get(db, key, value, flags) ;
#ifdef DB_VERSION_MAJOR
      if (RETVAL > 0)
        RETVAL = -1 ;
      else if (RETVAL == DB_NOTFOUND)
        RETVAL = 1 ;
#endif
    OUTPUT:
      RETVAL
      value

int
db_put(db, key, value, flags=0)
    DB_File     db
    DBTKEY      key
    DBT     value
    u_int       flags
    PREINIT:
      dMY_CXT;
    CODE:
      CurrentDB = db ;
      RETVAL = db_put(db, key, value, flags) ;
#ifdef DB_VERSION_MAJOR
      if (RETVAL > 0)
        RETVAL = -1 ;
      else if (RETVAL == DB_KEYEXIST)
        RETVAL = 1 ;
#endif
    OUTPUT:
      RETVAL
      key       if (flagSet(flags, R_IAFTER) || flagSet(flags, R_IBEFORE)) OutputKey(ST(1), key);

int
db_fd(db)
    DB_File     db
    PREINIT:
      dMY_CXT ;
    CODE:
      CurrentDB = db ;
#ifdef DB_VERSION_MAJOR
      RETVAL = -1 ;
      {
        int status = 0 ;
        status = (db->in_memory
                  ? -1
                  : ((db->dbp)->fd)(db->dbp, &RETVAL) ) ;
        if (status != 0)
          RETVAL = -1 ;
      }
#else
      RETVAL = (db->in_memory
                ? -1
                : ((db->dbp)->fd)(db->dbp) ) ;
#endif
    OUTPUT:
      RETVAL

int
db_sync(db, flags=0)
    DB_File     db
    u_int       flags
    PREINIT:
      dMY_CXT;
    CODE:
      CurrentDB = db ;
      RETVAL = db_sync(db, flags) ;
#ifdef DB_VERSION_MAJOR
      if (RETVAL > 0)
        RETVAL = -1 ;
#endif
    OUTPUT:
      RETVAL


int
db_seq(db, key, value, flags)
    DB_File     db
    DBTKEY      key
    DBT     value = NO_INIT
    u_int       flags
    PREINIT:
      dMY_CXT;
    CODE:
      CurrentDB = db ;
      DBT_clear(value) ;
      RETVAL = db_seq(db, key, value, flags);
#ifdef DB_VERSION_MAJOR
      if (RETVAL > 0)
        RETVAL = -1 ;
      else if (RETVAL == DB_NOTFOUND)
        RETVAL = 1 ;
#endif
    OUTPUT:
      RETVAL
      key
      value

SV *
filter_fetch_key(db, code)
    DB_File     db
    SV *        code
    SV *        RETVAL = &PL_sv_undef ;
    CODE:
        DBM_setFilter(db->filter_fetch_key, code) ;

SV *
filter_store_key(db, code)
    DB_File     db
    SV *        code
    SV *        RETVAL = &PL_sv_undef ;
    CODE:
        DBM_setFilter(db->filter_store_key, code) ;

SV *
filter_fetch_value(db, code)
    DB_File     db
    SV *        code
    SV *        RETVAL = &PL_sv_undef ;
    CODE:
        DBM_setFilter(db->filter_fetch_value, code) ;

SV *
filter_store_value(db, code)
    DB_File     db
    SV *        code
    SV *        RETVAL = &PL_sv_undef ;
    CODE:
        DBM_setFilter(db->filter_store_value, code) ;