zlib: ensure user provided memory functions are used by zlib, when given

As a bonus, this lets our MemoryTracking subsystem track zlib operations. And also fixes a shortcut some zlib 1.2.x versions took using malloc() instead of calloc(), which would trigger memory debuggers warnings on memory being used without having been initialized.

zlib: ensure user provided memory functions are used by zlib, when given
1c400b4e · Yang Tse · 61ae7e9c · 1c400b4e · 1c400b4e
Commit 1c400b4e authored 13 years ago by Yang Tse
--- a/lib/content_encoding.c
+++ b/lib/content_encoding.c
@@ -49,6 +49,21 @@
 #define COMMENT      0x10 /* bit 4 set: file comment present */
 #define RESERVED     0xE0 /* bits 5..7: reserved */

+static voidpf
+zalloc_cb(voidpf opaque, unsigned int items, unsigned int size)
+{
+  (void) opaque;
+  /* not a typo, keep it calloc() */
+  return (voidpf) calloc(items, size);
+}
+
+static void
+zfree_cb(voidpf opaque, voidpf ptr)
+{
+  (void) opaque;
+  free(ptr);
+}
+
 static CURLcode
 process_zlib_error(struct connectdata *conn, z_stream *z)
 {
@@ -159,6 +174,9 @@ Curl_unencode_deflate_write(struct connectdata *conn,
  /* Initialize zlib? */
  if(k->zlib_init == ZLIB_UNINIT) {
    memset(z, 0, sizeof(z_stream));
+    z->zalloc = (alloc_func)zalloc_cb;
+    z->zfree = (free_func)zfree_cb;
+
    if(inflateInit(z) != Z_OK)
      return process_zlib_error(conn, z);
    k->zlib_init = ZLIB_INIT;
@@ -266,6 +284,8 @@ Curl_unencode_gzip_write(struct connectdata *conn,
  /* Initialize zlib? */
  if(k->zlib_init == ZLIB_UNINIT) {
    memset(z, 0, sizeof(z_stream));
+    z->zalloc = (alloc_func)zalloc_cb;
+    z->zfree = (free_func)zfree_cb;

    if(strcmp(zlibVersion(), "1.2.0.4") >= 0) {
      /* zlib ver. >= 1.2.0.4 supports transparent gzip decompressing */

--- a/src/mkhelp.pl
+++ b/src/mkhelp.pl
@@ -133,7 +133,6 @@ print <<HEAD
 * NEVER EVER edit this manually, fix the mkhelp.pl script instead!
 * Generation time: $now
 */
-#include "setup.h"
 #ifdef USE_MANUAL
 #include "hugehelp.h"
 HEAD
@@ -141,6 +140,9 @@ HEAD
 if($c) {
    print <<HEAD
 #include <zlib.h>
+#if defined(CURLDEBUG) && defined(CURLTOOLDEBUG)
+#include "memdebug.h"
+#endif
 static const unsigned char hugehelpgz[] = {
  /* This mumbo-jumbo is the huge help text compressed with gzip.
     Thanks to this operation, the size of this data shrunk from $gzip
@@ -165,6 +167,17 @@ HEAD

    print <<EOF
 #define BUF_SIZE 0x10000
+static voidpf zalloc_func(voidpf opaque, unsigned int items, unsigned int size)
+{
+  (void) opaque;
+  /* not a typo, keep it calloc() */
+  return (voidpf) calloc(items, size);
+}
+static void zfree_func(voidpf opaque, voidpf ptr)
+{
+  (void) opaque;
+  free(ptr);
+}
 /* Decompress and send to stdout a gzip-compressed buffer */
 void hugehelp(void)
 {
@@ -178,6 +191,8 @@ void hugehelp(void)

  headerlen = 10;
  memset(&z, 0, sizeof(z_stream));
+  z.zalloc = (alloc_func)zalloc_func;
+  z.zfree = (free_func)zfree_func;
  z.avail_in = (unsigned int)(sizeof(hugehelpgz) - headerlen);
  z.next_in = (unsigned char *)hugehelpgz + headerlen;