fix(lua-cjson): handle the large string correctly (#11281)

Patch lua-cjson to make it can process a large string correctly.

OpenResty PR: openresty/lua-cjson#94

KAG-2151

(cherry picked from commit 65de2c3)

build/openresty/patches/lua-cjson-2.1.0.10_02-handle-large-string-correctly.patch

@@ -0,0 +1,387 @@
+diff --git a/bundle/lua-cjson-2.1.0.10/lua_cjson.c b/bundle/lua-cjson-2.1.0.10/lua_cjson.c
+index ff61c47..3b055c4 100644
+--- a/bundle/lua-cjson-2.1.0.10/lua_cjson.c
++++ b/bundle/lua-cjson-2.1.0.10/lua_cjson.c
+@@ -40,6 +40,7 @@
+ #include <stdint.h>
+ #include <string.h>
+ #include <math.h>
++#include <stdint.h>
+ #include <limits.h>
+ #include <lua.h>
+ #include <lauxlib.h>
+@@ -177,13 +178,13 @@ typedef struct {
+
+ typedef struct {
+     json_token_type_t type;
+-    int index;
++    size_t index;
+     union {
+         const char *string;
+         double number;
+         int boolean;
+     } value;
+-    int string_len;
++    size_t string_len;
+ } json_token_t;
+
+ static const char *char2escape[256] = {
+@@ -544,6 +545,8 @@ static void json_append_string(lua_State *l, strbuf_t *json, int lindex)
+      * This buffer is reused constantly for small strings
+      * If there are any excess pages, they won't be hit anyway.
+      * This gains ~5% speedup. */
++    if (len > SIZE_MAX / 6 - 3)
++        abort(); /* Overflow check */
+     strbuf_ensure_empty_length(json, len * 6 + 2);
+
+     strbuf_append_char_unsafe(json, '\"');
+@@ -818,7 +821,7 @@ static int json_encode(lua_State *l)
+     strbuf_t local_encode_buf;
+     strbuf_t *encode_buf;
+     char *json;
+-    int len;
++    size_t len;
+
+     luaL_argcheck(l, lua_gettop(l) == 1, 1, "expected 1 argument");
+
+diff --git a/bundle/lua-cjson-2.1.0.10/strbuf.c b/bundle/lua-cjson-2.1.0.10/strbuf.c
+index ed13367..2dc30be 100644
+--- a/bundle/lua-cjson-2.1.0.10/strbuf.c
++++ b/bundle/lua-cjson-2.1.0.10/strbuf.c
+@@ -26,6 +26,7 @@
+ #include <stdlib.h>
+ #include <stdarg.h>
+ #include <string.h>
++#include <stdint.h>
+
+ #include "strbuf.h"
+
+@@ -38,22 +39,22 @@ static void die(const char *fmt, ...)
+     va_end(arg);
+     fprintf(stderr, "\n");
+
+-    exit(-1);
++    abort();
+ }
+
+-void strbuf_init(strbuf_t *s, int len)
++void strbuf_init(strbuf_t *s, size_t len)
+ {
+-    int size;
++    size_t size;
+
+-    if (len <= 0)
++    if (!len)
+         size = STRBUF_DEFAULT_SIZE;
+     else
+-        size = len + 1;         /* \0 terminator */
+-
++        size = len + 1;
++    if (size < len)
++        die("Overflow, len: %zu", len);
+     s->buf = NULL;
+     s->size = size;
+     s->length = 0;
+-    s->increment = STRBUF_DEFAULT_INCREMENT;
+     s->dynamic = 0;
+     s->reallocs = 0;
+     s->debug = 0;
+@@ -65,7 +66,7 @@ void strbuf_init(strbuf_t *s, int len)
+     strbuf_ensure_null(s);
+ }
+
+-strbuf_t *strbuf_new(int len)
++strbuf_t *strbuf_new(size_t len)
+ {
+     strbuf_t *s;
+
+@@ -81,20 +82,10 @@ strbuf_t *strbuf_new(int len)
+     return s;
+ }
+
+-void strbuf_set_increment(strbuf_t *s, int increment)
+-{
+-    /* Increment > 0:  Linear buffer growth rate
+-     * Increment < -1: Exponential buffer growth rate */
+-    if (increment == 0 || increment == -1)
+-        die("BUG: Invalid string increment");
+-
+-    s->increment = increment;
+-}
+-
+ static inline void debug_stats(strbuf_t *s)
+ {
+     if (s->debug) {
+-        fprintf(stderr, "strbuf(%lx) reallocs: %d, length: %d, size: %d\n",
++        fprintf(stderr, "strbuf(%lx) reallocs: %d, length: %zd, size: %zd\n",
+                 (long)s, s->reallocs, s->length, s->size);
+     }
+ }
+@@ -113,7 +104,7 @@ void strbuf_free(strbuf_t *s)
+         free(s);
+ }
+
+-char *strbuf_free_to_string(strbuf_t *s, int *len)
++char *strbuf_free_to_string(strbuf_t *s, size_t *len)
+ {
+     char *buf;
+
+@@ -131,57 +122,63 @@ char *strbuf_free_to_string(strbuf_t *s, int *len)
+     return buf;
+ }
+
+-static int calculate_new_size(strbuf_t *s, int len)
++static size_t calculate_new_size(strbuf_t *s, size_t len)
+ {
+-    int reqsize, newsize;
++    size_t reqsize, newsize;
+
+     if (len <= 0)
+         die("BUG: Invalid strbuf length requested");
+
+     /* Ensure there is room for optional NULL termination */
+     reqsize = len + 1;
++    if (reqsize < len)
++        die("Overflow, len: %zu", len);
+
+     /* If the user has requested to shrink the buffer, do it exactly */
+     if (s->size > reqsize)
+         return reqsize;
+
+     newsize = s->size;
+-    if (s->increment < 0) {
++    if (reqsize >= SIZE_MAX / 2) {
++        newsize = reqsize;
++    } else {
+         /* Exponential sizing */
+         while (newsize < reqsize)
+-            newsize *= -s->increment;
+-    } else if (s->increment != 0)  {
+-        /* Linear sizing */
+-        newsize = ((newsize + s->increment - 1) / s->increment) * s->increment;
++            newsize *= 2;
+     }
+
++    if (newsize < reqsize)
++        die("BUG: strbuf length would overflow, len: %zu", len);
++
++
+     return newsize;
+ }
+
+
+ /* Ensure strbuf can handle a string length bytes long (ignoring NULL
+  * optional termination). */
+-void strbuf_resize(strbuf_t *s, int len)
++void strbuf_resize(strbuf_t *s, size_t len)
+ {
+-    int newsize;
++    size_t newsize;
+
+     newsize = calculate_new_size(s, len);
+
+     if (s->debug > 1) {
+-        fprintf(stderr, "strbuf(%lx) resize: %d => %d\n",
++        fprintf(stderr, "strbuf(%lx) resize: %zd => %zd\n",
+                 (long)s, s->size, newsize);
+     }
+
+     s->size = newsize;
+     s->buf = realloc(s->buf, s->size);
+     if (!s->buf)
+-        die("Out of memory");
++        die("Out of memory, len: %zu", len);
+     s->reallocs++;
+ }
+
+ void strbuf_append_string(strbuf_t *s, const char *str)
+ {
+-    int space, i;
++    int i;
++    size_t space;
+
+     space = strbuf_empty_length(s);
+
+@@ -197,55 +194,6 @@ void strbuf_append_string(strbuf_t *s, const char *str)
+     }
+ }
+
+-/* strbuf_append_fmt() should only be used when an upper bound
+- * is known for the output string. */
+-void strbuf_append_fmt(strbuf_t *s, int len, const char *fmt, ...)
+-{
+-    va_list arg;
+-    int fmt_len;
+-
+-    strbuf_ensure_empty_length(s, len);
+-
+-    va_start(arg, fmt);
+-    fmt_len = vsnprintf(s->buf + s->length, len, fmt, arg);
+-    va_end(arg);
+-
+-    if (fmt_len < 0)
+-        die("BUG: Unable to convert number");  /* This should never happen.. */
+-
+-    s->length += fmt_len;
+-}
+-
+-/* strbuf_append_fmt_retry() can be used when the there is no known
+- * upper bound for the output string. */
+-void strbuf_append_fmt_retry(strbuf_t *s, const char *fmt, ...)
+-{
+-    va_list arg;
+-    int fmt_len, try;
+-    int empty_len;
+-
+-    /* If the first attempt to append fails, resize the buffer appropriately
+-     * and try again */
+-    for (try = 0; ; try++) {
+-        va_start(arg, fmt);
+-        /* Append the new formatted string */
+-        /* fmt_len is the length of the string required, excluding the
+-         * trailing NULL */
+-        empty_len = strbuf_empty_length(s);
+-        /* Add 1 since there is also space to store the terminating NULL. */
+-        fmt_len = vsnprintf(s->buf + s->length, empty_len + 1, fmt, arg);
+-        va_end(arg);
+-
+-        if (fmt_len <= empty_len)
+-            break;  /* SUCCESS */
+-        if (try > 0)
+-            die("BUG: length of formatted string changed");
+-
+-        strbuf_resize(s, s->length + fmt_len);
+-    }
+-
+-    s->length += fmt_len;
+-}
+
+ /* vi:ai et sw=4 ts=4:
+  */
+diff --git a/bundle/lua-cjson-2.1.0.10/strbuf.h b/bundle/lua-cjson-2.1.0.10/strbuf.h
+index 5df0b7b..d77e0f4 100644
+--- a/bundle/lua-cjson-2.1.0.10/strbuf.h
++++ b/bundle/lua-cjson-2.1.0.10/strbuf.h
+@@ -32,15 +32,13 @@
+
+ /* Size: Total bytes allocated to *buf
+  * Length: String length, excluding optional NULL terminator.
+- * Increment: Allocation increments when resizing the string buffer.
+  * Dynamic: True if created via strbuf_new()
+  */
+
+ typedef struct {
+     char *buf;
+-    int size;
+-    int length;
+-    int increment;
++    size_t size;
++    size_t length;
+     int dynamic;
+     int reallocs;
+     int debug;
+@@ -49,32 +47,27 @@ typedef struct {
+ #ifndef STRBUF_DEFAULT_SIZE
+ #define STRBUF_DEFAULT_SIZE 1023
+ #endif
+-#ifndef STRBUF_DEFAULT_INCREMENT
+-#define STRBUF_DEFAULT_INCREMENT -2
+-#endif
+
+ /* Initialise */
+-extern strbuf_t *strbuf_new(int len);
+-extern void strbuf_init(strbuf_t *s, int len);
+-extern void strbuf_set_increment(strbuf_t *s, int increment);
++extern strbuf_t *strbuf_new(size_t len);
++extern void strbuf_init(strbuf_t *s, size_t len);
+
+ /* Release */
+ extern void strbuf_free(strbuf_t *s);
+-extern char *strbuf_free_to_string(strbuf_t *s, int *len);
++extern char *strbuf_free_to_string(strbuf_t *s, size_t *len);
+
+ /* Management */
+-extern void strbuf_resize(strbuf_t *s, int len);
+-static int strbuf_empty_length(strbuf_t *s);
+-static int strbuf_length(strbuf_t *s);
+-static char *strbuf_string(strbuf_t *s, int *len);
+-static void strbuf_ensure_empty_length(strbuf_t *s, int len);
++extern void strbuf_resize(strbuf_t *s, size_t len);
++static size_t strbuf_empty_length(strbuf_t *s);
++static size_t strbuf_length(strbuf_t *s);
++static char *strbuf_string(strbuf_t *s, size_t *len);
++static void strbuf_ensure_empty_length(strbuf_t *s, size_t len);
+ static char *strbuf_empty_ptr(strbuf_t *s);
+-static void strbuf_extend_length(strbuf_t *s, int len);
++static void strbuf_extend_length(strbuf_t *s, size_t len);
++static void strbuf_set_length(strbuf_t *s, int len);
+
+ /* Update */
+-extern void strbuf_append_fmt(strbuf_t *s, int len, const char *fmt, ...);
+-extern void strbuf_append_fmt_retry(strbuf_t *s, const char *format, ...);
+-static void strbuf_append_mem(strbuf_t *s, const char *c, int len);
++static void strbuf_append_mem(strbuf_t *s, const char *c, size_t len);
+ extern void strbuf_append_string(strbuf_t *s, const char *str);
+ static void strbuf_append_char(strbuf_t *s, const char c);
+ static void strbuf_ensure_null(strbuf_t *s);
+@@ -92,12 +85,12 @@ static inline int strbuf_allocated(strbuf_t *s)
+
+ /* Return bytes remaining in the string buffer
+  * Ensure there is space for a NULL terminator. */
+-static inline int strbuf_empty_length(strbuf_t *s)
++static inline size_t strbuf_empty_length(strbuf_t *s)
+ {
+     return s->size - s->length - 1;
+ }
+
+-static inline void strbuf_ensure_empty_length(strbuf_t *s, int len)
++static inline void strbuf_ensure_empty_length(strbuf_t *s, size_t len)
+ {
+     if (len > strbuf_empty_length(s))
+         strbuf_resize(s, s->length + len);
+@@ -108,12 +101,17 @@ static inline char *strbuf_empty_ptr(strbuf_t *s)
+     return s->buf + s->length;
+ }
+
+-static inline void strbuf_extend_length(strbuf_t *s, int len)
++static inline void strbuf_set_length(strbuf_t *s, int len)
++{
++    s->length = len;
++}
++
++static inline void strbuf_extend_length(strbuf_t *s, size_t len)
+ {
+     s->length += len;
+ }
+
+-static inline int strbuf_length(strbuf_t *s)
++static inline size_t strbuf_length(strbuf_t *s)
+ {
+     return s->length;
+ }
+@@ -129,14 +127,14 @@ static inline void strbuf_append_char_unsafe(strbuf_t *s, const char c)
+     s->buf[s->length++] = c;
+ }
+
+-static inline void strbuf_append_mem(strbuf_t *s, const char *c, int len)
++static inline void strbuf_append_mem(strbuf_t *s, const char *c, size_t len)
+ {
+     strbuf_ensure_empty_length(s, len);
+     memcpy(s->buf + s->length, c, len);
+     s->length += len;
+ }
+
+-static inline void strbuf_append_mem_unsafe(strbuf_t *s, const char *c, int len)
++static inline void strbuf_append_mem_unsafe(strbuf_t *s, const char *c, size_t len)
+ {
+     memcpy(s->buf + s->length, c, len);
+     s->length += len;
+@@ -147,7 +145,7 @@ static inline void strbuf_ensure_null(strbuf_t *s)
+     s->buf[s->length] = 0;
+ }
+
+-static inline char *strbuf_string(strbuf_t *s, int *len)
++static inline char *strbuf_string(strbuf_t *s, size_t *len)
+ {
+     if (len)
+         *len = s->length;