Merge in from trunk r64802 - r68625

[wxWidgets.git] / src / png / pngmem.c

diff --git a/src/png/pngmem.c b/src/png/pngmem.c
index 06c4c1b7ea30b7a60958da87f3768658bf4d54eb..c8a3f6f59af1c9acc6bb176b5aced7d8c3d3508b 100644 (file)
--- a/src/png/pngmem.c
+++ b/src/png/pngmem.c
@@ -1,11 +1,14 @@
 
 /* pngmem.c - stub functions for memory allocation
  *
 
 /* pngmem.c - stub functions for memory allocation
  *

- * libpng 1.0.3 - January 14, 1999
- * For conditions of distribution and use, see copyright notice in png.h
- * Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.
- * Copyright (c) 1996, 1997 Andreas Dilger
- * Copyright (c) 1998, 1999 Glenn Randers-Pehrson
+ * Last changed in libpng 1.4.2 [May 6, 2010]
+ * Copyright (c) 1998-2010 Glenn Randers-Pehrson
+ * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
+ * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
+ *
+ * This code is released under the libpng license.
+ * For conditions of distribution and use, see the disclaimer
+ * and license in png.h

  *
  * This file provides a location for all memory allocation.  Users who
  * need special memory handling are expected to supply replacement
  *
  * This file provides a location for all memory allocation.  Users who
  * need special memory handling are expected to supply replacement


@@ -14,80 +17,82 @@
  * identify the replacement functions.
  */
 
  * identify the replacement functions.
  */
 

-#define PNG_INTERNAL
+#define PNG_NO_PEDANTIC_WARNINGS

 #include "png.h"
 #include "png.h"

+#if defined(PNG_READ_SUPPORTED) || defined(PNG_WRITE_SUPPORTED)
+#include "pngpriv.h"

 
 /* Borland DOS special memory handler */
 #if defined(__TURBOC__) && !defined(_Windows) && !defined(__FLAT__)
 
 /* Borland DOS special memory handler */
 #if defined(__TURBOC__) && !defined(_Windows) && !defined(__FLAT__)

-/* if you change this, be sure to change the one in png.h also */
+/* If you change this, be sure to change the one in png.h also */

 
 /* Allocate memory for a png_struct.  The malloc and memset can be replaced
    by a single call to calloc() if this is thought to improve performance. */
 
 /* Allocate memory for a png_struct.  The malloc and memset can be replaced
    by a single call to calloc() if this is thought to improve performance. */

-png_voidp
+png_voidp /* PRIVATE */

 png_create_struct(int type)
 {
 #ifdef PNG_USER_MEM_SUPPORTED
 png_create_struct(int type)
 {
 #ifdef PNG_USER_MEM_SUPPORTED

-   return (png_create_struct_2(type, NULL));
+   return (png_create_struct_2(type, NULL, NULL));

 }
 
 /* Alternate version of png_create_struct, for use with user-defined malloc. */
 }
 
 /* Alternate version of png_create_struct, for use with user-defined malloc. */

-png_voidp
-png_create_struct_2(int type, png_malloc_ptr malloc_fn)
+png_voidp /* PRIVATE */
+png_create_struct_2(int type, png_malloc_ptr malloc_fn, png_voidp mem_ptr)

 {
 #endif /* PNG_USER_MEM_SUPPORTED */
    png_size_t size;
    png_voidp struct_ptr;
 
    if (type == PNG_STRUCT_INFO)
 {
 #endif /* PNG_USER_MEM_SUPPORTED */
    png_size_t size;
    png_voidp struct_ptr;
 
    if (type == PNG_STRUCT_INFO)

-     size = sizeof(png_info);
+      size = png_sizeof(png_info);

    else if (type == PNG_STRUCT_PNG)
    else if (type == PNG_STRUCT_PNG)

-     size = sizeof(png_struct);
+      size = png_sizeof(png_struct);

    else
    else

-     return ((png_voidp)NULL);
+      return (png_get_copyright(NULL));

 
 #ifdef PNG_USER_MEM_SUPPORTED
 
 #ifdef PNG_USER_MEM_SUPPORTED

-   if(malloc_fn != NULL)
+   if (malloc_fn != NULL)

    {
    {

-      if ((struct_ptr = (*(malloc_fn))(NULL, size)) != NULL)
-         png_memset(struct_ptr, 0, size);
-         return (struct_ptr);
+      png_struct dummy_struct;
+      png_structp png_ptr = &dummy_struct;
+      png_ptr->mem_ptr=mem_ptr;
+      struct_ptr = (*(malloc_fn))(png_ptr, (png_uint_32)size);

    }
    }

+   else

 #endif /* PNG_USER_MEM_SUPPORTED */
 #endif /* PNG_USER_MEM_SUPPORTED */

-   if ((struct_ptr = (png_voidp)farmalloc(size)) != NULL)
-   {
+   struct_ptr = (png_voidp)farmalloc(size);
+   if (struct_ptr != NULL)

       png_memset(struct_ptr, 0, size);
       png_memset(struct_ptr, 0, size);

-   }

    return (struct_ptr);
 }
 
    return (struct_ptr);
 }
 

-

 /* Free memory allocated by a png_create_struct() call */
 /* Free memory allocated by a png_create_struct() call */

-void
+void /* PRIVATE */

 png_destroy_struct(png_voidp struct_ptr)
 {
 #ifdef PNG_USER_MEM_SUPPORTED
 png_destroy_struct(png_voidp struct_ptr)
 {
 #ifdef PNG_USER_MEM_SUPPORTED

-   png_destroy_struct_2(struct_ptr, (png_free_ptr)NULL);
+   png_destroy_struct_2(struct_ptr, NULL, NULL);

 }
 
 /* Free memory allocated by a png_create_struct() call */
 }
 
 /* Free memory allocated by a png_create_struct() call */

-void
-png_destroy_struct_2(png_voidp struct_ptr, png_free_ptr free_fn)
+void /* PRIVATE */
+png_destroy_struct_2(png_voidp struct_ptr, png_free_ptr free_fn,
+    png_voidp mem_ptr)

 {
 #endif
    if (struct_ptr != NULL)
    {
 #ifdef PNG_USER_MEM_SUPPORTED
 {
 #endif
    if (struct_ptr != NULL)
    {
 #ifdef PNG_USER_MEM_SUPPORTED

-      if(free_fn != NULL)
+      if (free_fn != NULL)

       {
          png_struct dummy_struct;
          png_structp png_ptr = &dummy_struct;
       {
          png_struct dummy_struct;
          png_structp png_ptr = &dummy_struct;

+         png_ptr->mem_ptr=mem_ptr;

          (*(free_fn))(png_ptr, struct_ptr);
          (*(free_fn))(png_ptr, struct_ptr);

-         struct_ptr = NULL;

          return;
       }
 #endif /* PNG_USER_MEM_SUPPORTED */
       farfree (struct_ptr);
          return;
       }
 #endif /* PNG_USER_MEM_SUPPORTED */
       farfree (struct_ptr);

-      struct_ptr = NULL;

    }
 }
 
    }
 }
 


@@ -110,38 +115,60 @@ png_destroy_struct_2(png_voidp struct_ptr, png_free_ptr free_fn)
  * result, we would be truncating potentially larger memory requests
  * (which should cause a fatal error) and introducing major problems.
  */
  * result, we would be truncating potentially larger memory requests
  * (which should cause a fatal error) and introducing major problems.
  */

-png_voidp
-png_malloc(png_structp png_ptr, png_uint_32 size)
+png_voidp PNGAPI
+png_calloc(png_structp png_ptr, png_alloc_size_t size)

 {
 {

-#ifndef PNG_USER_MEM_SUPPORTED

    png_voidp ret;
    png_voidp ret;

-#endif
+
+   ret = (png_malloc(png_ptr, size));
+   if (ret != NULL)
+      png_memset(ret,0,(png_size_t)size);
+   return (ret);
+}
+
+png_voidp PNGAPI
+png_malloc(png_structp png_ptr, png_alloc_size_t size)
+{
+   png_voidp ret;
+

    if (png_ptr == NULL || size == 0)
    if (png_ptr == NULL || size == 0)

-      return ((png_voidp)NULL);
+      return (NULL);

 
 #ifdef PNG_USER_MEM_SUPPORTED
 
 #ifdef PNG_USER_MEM_SUPPORTED

-   if(png_ptr->malloc_fn != NULL)
-       return ((png_voidp)(*(png_ptr->malloc_fn))(png_ptr, size));
+   if (png_ptr->malloc_fn != NULL)
+      ret = ((png_voidp)(*(png_ptr->malloc_fn))(png_ptr, (png_size_t)size));

    else
    else

-       return png_malloc_default(png_ptr, size);
+      ret = (png_malloc_default(png_ptr, size));
+   if (ret == NULL && (png_ptr->flags&PNG_FLAG_MALLOC_NULL_MEM_OK) == 0)
+       png_error(png_ptr, "Out of memory");
+   return (ret);

 }
 
 }
 

-png_voidp
-png_malloc_default(png_structp png_ptr, png_uint_32 size)
+png_voidp PNGAPI
+png_malloc_default(png_structp png_ptr, png_alloc_size_t size)

 {
    png_voidp ret;
 #endif /* PNG_USER_MEM_SUPPORTED */
 
 {
    png_voidp ret;
 #endif /* PNG_USER_MEM_SUPPORTED */
 

+   if (png_ptr == NULL || size == 0)
+      return (NULL);
+

 #ifdef PNG_MAX_MALLOC_64K
    if (size > (png_uint_32)65536L)
 #ifdef PNG_MAX_MALLOC_64K
    if (size > (png_uint_32)65536L)

-      png_error(png_ptr, "Cannot Allocate > 64K");
+   {
+      png_warning(png_ptr, "Cannot Allocate > 64K");
+      ret = NULL;
+   }
+   else

 #endif
 
 #endif
 

-   if (size == (png_uint_32)65536L)
+   if (size != (size_t)size)
+      ret = NULL;
+   else if (size == (png_uint_32)65536L)

    {
       if (png_ptr->offset_table == NULL)
       {
    {
       if (png_ptr->offset_table == NULL)
       {

-         /* try to see if we need to do any of this fancy stuff */
+         /* Try to see if we need to do any of this fancy stuff */

          ret = farmalloc(size);
          if (ret == NULL || ((png_size_t)ret & 0xffff))
          {
          ret = farmalloc(size);
          if (ret == NULL || ((png_size_t)ret & 0xffff))
          {


@@ -157,8 +184,9 @@ png_malloc_default(png_structp png_ptr, png_uint_32 size)
                ret = NULL;
             }
 
                ret = NULL;
             }
 

-            num_blocks = (int)(1 << (png_ptr->zlib_window_bits - 14));
-            if (num_blocks < 1)
+            if (png_ptr->zlib_window_bits > 14)
+               num_blocks = (int)(1 << (png_ptr->zlib_window_bits - 14));
+            else

                num_blocks = 1;
             if (png_ptr->zlib_mem_level >= 7)
                num_blocks += (int)(1 << (png_ptr->zlib_mem_level - 7));
                num_blocks = 1;
             if (png_ptr->zlib_mem_level >= 7)
                num_blocks += (int)(1 << (png_ptr->zlib_mem_level - 7));


@@ -171,33 +199,53 @@ png_malloc_default(png_structp png_ptr, png_uint_32 size)
 
             if (table == NULL)
             {
 
             if (table == NULL)
             {

-               png_error(png_ptr, "Out Of Memory."); /* Note "O" and "M" */
+#ifndef PNG_USER_MEM_SUPPORTED
+               if ((png_ptr->flags&PNG_FLAG_MALLOC_NULL_MEM_OK) == 0)
+                  png_error(png_ptr, "Out Of Memory"); /* Note "O", "M" */
+               else
+                  png_warning(png_ptr, "Out Of Memory");
+#endif
+               return (NULL);

             }
 
             if ((png_size_t)table & 0xfff0)
             {
             }
 
             if ((png_size_t)table & 0xfff0)
             {

-               png_error(png_ptr, "Farmalloc didn't return normalized pointer");
+#ifndef PNG_USER_MEM_SUPPORTED
+               if ((png_ptr->flags&PNG_FLAG_MALLOC_NULL_MEM_OK) == 0)
+                  png_error(png_ptr,
+                    "Farmalloc didn't return normalized pointer");
+               else
+                  png_warning(png_ptr,
+                    "Farmalloc didn't return normalized pointer");
+#endif
+               return (NULL);

             }
 
             png_ptr->offset_table = table;
             png_ptr->offset_table_ptr = farmalloc(num_blocks *
             }
 
             png_ptr->offset_table = table;
             png_ptr->offset_table_ptr = farmalloc(num_blocks *

-               sizeof (png_bytep));
+               png_sizeof(png_bytep));

 
             if (png_ptr->offset_table_ptr == NULL)
             {
 
             if (png_ptr->offset_table_ptr == NULL)
             {

-               png_error(png_ptr, "Out Of memory.");
+#ifndef PNG_USER_MEM_SUPPORTED
+               if ((png_ptr->flags&PNG_FLAG_MALLOC_NULL_MEM_OK) == 0)
+                  png_error(png_ptr, "Out Of memory"); /* Note "O", "m" */
+               else
+                  png_warning(png_ptr, "Out Of memory");
+#endif
+               return (NULL);

             }
 
             hptr = (png_byte huge *)table;
             if ((png_size_t)hptr & 0xf)
             {
                hptr = (png_byte huge *)((long)(hptr) & 0xfffffff0L);
             }
 
             hptr = (png_byte huge *)table;
             if ((png_size_t)hptr & 0xf)
             {
                hptr = (png_byte huge *)((long)(hptr) & 0xfffffff0L);

-               hptr += 16L;
+               hptr = hptr + 16L;  /* "hptr += 16L" fails on Turbo C++ 3.0 */

             }
             for (i = 0; i < num_blocks; i++)
             {
                png_ptr->offset_table_ptr[i] = (png_bytep)hptr;
             }
             for (i = 0; i < num_blocks; i++)
             {
                png_ptr->offset_table_ptr[i] = (png_bytep)hptr;

-               hptr += (png_uint_32)65536L;
+               hptr = hptr + (png_uint_32)65536L;  /* "+=" fails on TC++3.0 */

             }
 
             png_ptr->offset_table_number = num_blocks;
             }
 
             png_ptr->offset_table_number = num_blocks;


@@ -207,25 +255,39 @@ png_malloc_default(png_structp png_ptr, png_uint_32 size)
       }
 
       if (png_ptr->offset_table_count >= png_ptr->offset_table_number)
       }
 
       if (png_ptr->offset_table_count >= png_ptr->offset_table_number)

-         png_error(png_ptr, "Out of Memory.");
+      {
+#ifndef PNG_USER_MEM_SUPPORTED
+         if ((png_ptr->flags&PNG_FLAG_MALLOC_NULL_MEM_OK) == 0)
+            png_error(png_ptr, "Out of Memory"); /* Note "o" and "M" */
+         else
+            png_warning(png_ptr, "Out of Memory");
+#endif
+         return (NULL);
+      }

 
       ret = png_ptr->offset_table_ptr[png_ptr->offset_table_count++];
    }
    else
       ret = farmalloc(size);
 
 
       ret = png_ptr->offset_table_ptr[png_ptr->offset_table_count++];
    }
    else
       ret = farmalloc(size);
 

+#ifndef PNG_USER_MEM_SUPPORTED

    if (ret == NULL)
    {
    if (ret == NULL)
    {

-      png_error(png_ptr, "Out of memory."); /* Note "o" and "m" */
+      if ((png_ptr->flags&PNG_FLAG_MALLOC_NULL_MEM_OK) == 0)
+         png_error(png_ptr, "Out of memory"); /* Note "o" and "m" */
+      else
+         png_warning(png_ptr, "Out of memory"); /* Note "o" and "m" */

    }
    }

+#endif

 
    return (ret);
 }
 
 
    return (ret);
 }
 

-/* free a pointer allocated by png_malloc().  In the default
-   configuration, png_ptr is not used, but is passed in case it
-   is needed.  If ptr is NULL, return without taking any action. */
-void
+/* Free a pointer allocated by png_malloc().  In the default
+ * configuration, png_ptr is not used, but is passed in case it
+ * is needed.  If ptr is NULL, return without taking any action.
+ */
+void PNGAPI

 png_free(png_structp png_ptr, png_voidp ptr)
 {
    if (png_ptr == NULL || ptr == NULL)
 png_free(png_structp png_ptr, png_voidp ptr)
 {
    if (png_ptr == NULL || ptr == NULL)


@@ -235,17 +297,20 @@ png_free(png_structp png_ptr, png_voidp ptr)
    if (png_ptr->free_fn != NULL)
    {
       (*(png_ptr->free_fn))(png_ptr, ptr);
    if (png_ptr->free_fn != NULL)
    {
       (*(png_ptr->free_fn))(png_ptr, ptr);

-      ptr = NULL;

       return;
    }
       return;
    }

-   else png_free_default(png_ptr, ptr);
+   else
+      png_free_default(png_ptr, ptr);

 }
 
 }
 

-void
+void PNGAPI

 png_free_default(png_structp png_ptr, png_voidp ptr)
 {
 #endif /* PNG_USER_MEM_SUPPORTED */
 
 png_free_default(png_structp png_ptr, png_voidp ptr)
 {
 #endif /* PNG_USER_MEM_SUPPORTED */
 

+   if (png_ptr == NULL || ptr == NULL)
+      return;
+

    if (png_ptr->offset_table != NULL)
    {
       int i;
    if (png_ptr->offset_table != NULL)
    {
       int i;


@@ -271,7 +336,6 @@ png_free_default(png_structp png_ptr, png_voidp ptr)
    if (ptr != NULL)
    {
       farfree(ptr);
    if (ptr != NULL)
    {
       farfree(ptr);

-      ptr = NULL;

    }
 }
 
    }
 }
 


@@ -279,151 +343,187 @@ png_free_default(png_structp png_ptr, png_voidp ptr)
 
 /* Allocate memory for a png_struct or a png_info.  The malloc and
    memset can be replaced by a single call to calloc() if this is thought
 
 /* Allocate memory for a png_struct or a png_info.  The malloc and
    memset can be replaced by a single call to calloc() if this is thought

-   to improve performance noticably.*/
-png_voidp
+   to improve performance noticably. */
+png_voidp /* PRIVATE */

 png_create_struct(int type)
 {
 #ifdef PNG_USER_MEM_SUPPORTED
 png_create_struct(int type)
 {
 #ifdef PNG_USER_MEM_SUPPORTED

-   return (png_create_struct_2(type, NULL));
+   return (png_create_struct_2(type, NULL, NULL));

 }
 
 /* Allocate memory for a png_struct or a png_info.  The malloc and
    memset can be replaced by a single call to calloc() if this is thought
 }
 
 /* Allocate memory for a png_struct or a png_info.  The malloc and
    memset can be replaced by a single call to calloc() if this is thought

-   to improve performance noticably.*/
-png_voidp
-png_create_struct_2(int type, png_malloc_ptr malloc_fn)
+   to improve performance noticably. */
+png_voidp /* PRIVATE */
+png_create_struct_2(int type, png_malloc_ptr malloc_fn, png_voidp mem_ptr)

 {
 #endif /* PNG_USER_MEM_SUPPORTED */
    png_size_t size;
    png_voidp struct_ptr;
 
    if (type == PNG_STRUCT_INFO)
 {
 #endif /* PNG_USER_MEM_SUPPORTED */
    png_size_t size;
    png_voidp struct_ptr;
 
    if (type == PNG_STRUCT_INFO)

-      size = sizeof(png_info);
+      size = png_sizeof(png_info);

    else if (type == PNG_STRUCT_PNG)
    else if (type == PNG_STRUCT_PNG)

-      size = sizeof(png_struct);
+      size = png_sizeof(png_struct);

    else
    else

-      return ((png_voidp)NULL);
+      return (NULL);

 
 #ifdef PNG_USER_MEM_SUPPORTED
 
 #ifdef PNG_USER_MEM_SUPPORTED

-   if(malloc_fn != NULL)
+   if (malloc_fn != NULL)

    {
    {

-      if ((struct_ptr = (*(malloc_fn))(NULL, size)) != NULL)
+      png_struct dummy_struct;
+      png_structp png_ptr = &dummy_struct;
+      png_ptr->mem_ptr=mem_ptr;
+      struct_ptr = (*(malloc_fn))(png_ptr, size);
+      if (struct_ptr != NULL)

          png_memset(struct_ptr, 0, size);
       return (struct_ptr);
    }
 #endif /* PNG_USER_MEM_SUPPORTED */
 
 #if defined(__TURBOC__) && !defined(__FLAT__)
          png_memset(struct_ptr, 0, size);
       return (struct_ptr);
    }
 #endif /* PNG_USER_MEM_SUPPORTED */
 
 #if defined(__TURBOC__) && !defined(__FLAT__)

-   if ((struct_ptr = (png_voidp)farmalloc(size)) != NULL)
+   struct_ptr = (png_voidp)farmalloc(size);

 #else
 # if defined(_MSC_VER) && defined(MAXSEG_64K)
 #else
 # if defined(_MSC_VER) && defined(MAXSEG_64K)

-   if ((struct_ptr = (png_voidp)halloc(size,1)) != NULL)
+   struct_ptr = (png_voidp)halloc(size, 1);

 # else
 # else

-   if ((struct_ptr = (png_voidp)malloc(size)) != NULL)
+   struct_ptr = (png_voidp)malloc(size);

 # endif
 #endif
 # endif
 #endif

-   {
+   if (struct_ptr != NULL)

       png_memset(struct_ptr, 0, size);
       png_memset(struct_ptr, 0, size);

-   }

 
    return (struct_ptr);
 }
 
 
 /* Free memory allocated by a png_create_struct() call */
 
    return (struct_ptr);
 }
 
 
 /* Free memory allocated by a png_create_struct() call */

-void
+void /* PRIVATE */

 png_destroy_struct(png_voidp struct_ptr)
 {
 #ifdef PNG_USER_MEM_SUPPORTED
 png_destroy_struct(png_voidp struct_ptr)
 {
 #ifdef PNG_USER_MEM_SUPPORTED

-   png_destroy_struct_2(struct_ptr, (png_free_ptr)NULL);
+   png_destroy_struct_2(struct_ptr, NULL, NULL);

 }
 
 /* Free memory allocated by a png_create_struct() call */
 }
 
 /* Free memory allocated by a png_create_struct() call */

-void
-png_destroy_struct_2(png_voidp struct_ptr, png_free_ptr free_fn)
+void /* PRIVATE */
+png_destroy_struct_2(png_voidp struct_ptr, png_free_ptr free_fn,
+    png_voidp mem_ptr)

 {
 #endif /* PNG_USER_MEM_SUPPORTED */
    if (struct_ptr != NULL)
    {
 #ifdef PNG_USER_MEM_SUPPORTED
 {
 #endif /* PNG_USER_MEM_SUPPORTED */
    if (struct_ptr != NULL)
    {
 #ifdef PNG_USER_MEM_SUPPORTED

-      if(free_fn != NULL)
+      if (free_fn != NULL)

       {
          png_struct dummy_struct;
          png_structp png_ptr = &dummy_struct;
       {
          png_struct dummy_struct;
          png_structp png_ptr = &dummy_struct;

+         png_ptr->mem_ptr=mem_ptr;

          (*(free_fn))(png_ptr, struct_ptr);
          (*(free_fn))(png_ptr, struct_ptr);

-         struct_ptr = NULL;

          return;
       }
 #endif /* PNG_USER_MEM_SUPPORTED */
 #if defined(__TURBOC__) && !defined(__FLAT__)
       farfree(struct_ptr);
          return;
       }
 #endif /* PNG_USER_MEM_SUPPORTED */
 #if defined(__TURBOC__) && !defined(__FLAT__)
       farfree(struct_ptr);

-      struct_ptr = NULL;

 #else
 # if defined(_MSC_VER) && defined(MAXSEG_64K)
       hfree(struct_ptr);
 #else
 # if defined(_MSC_VER) && defined(MAXSEG_64K)
       hfree(struct_ptr);

-      struct_ptr = NULL;

 # else
       free(struct_ptr);
 # else
       free(struct_ptr);

-      struct_ptr = NULL;

 # endif
 #endif
    }
 }
 
 # endif
 #endif
    }
 }
 

-

 /* Allocate memory.  For reasonable files, size should never exceed
 /* Allocate memory.  For reasonable files, size should never exceed

-   64K.  However, zlib may allocate more then 64K if you don't tell
-   it not to.  See zconf.h and png.h for more information.  zlib does
-   need to allocate exactly 64K, so whatever you call here must
-   have the ability to do that. */
+ * 64K.  However, zlib may allocate more then 64K if you don't tell
+ * it not to.  See zconf.h and png.h for more information.  zlib does
+ * need to allocate exactly 64K, so whatever you call here must
+ * have the ability to do that.
+ */

 
 

-png_voidp
-png_malloc(png_structp png_ptr, png_uint_32 size)
+png_voidp PNGAPI
+png_calloc(png_structp png_ptr, png_alloc_size_t size)
+{
+   png_voidp ret;
+
+   ret = (png_malloc(png_ptr, size));
+   if (ret != NULL)
+      png_memset(ret,0,(png_size_t)size);
+   return (ret);
+}
+
+png_voidp PNGAPI
+png_malloc(png_structp png_ptr, png_alloc_size_t size)

 {
 {

-#ifndef PNG_USER_MEM_SUPPORTED

    png_voidp ret;
    png_voidp ret;

-#endif
-   if (png_ptr == NULL || size == 0)
-      return ((png_voidp)NULL);

 
 #ifdef PNG_USER_MEM_SUPPORTED
 
 #ifdef PNG_USER_MEM_SUPPORTED

-   if(png_ptr->malloc_fn != NULL)
-       return ((png_voidp)(*(png_ptr->malloc_fn))(png_ptr, size));
+   if (png_ptr == NULL || size == 0)
+      return (NULL);
+
+   if (png_ptr->malloc_fn != NULL)
+      ret = ((png_voidp)(*(png_ptr->malloc_fn))(png_ptr, (png_size_t)size));

    else
    else

-       return (png_malloc_default(png_ptr, size));
+      ret = (png_malloc_default(png_ptr, size));
+   if (ret == NULL && (png_ptr->flags&PNG_FLAG_MALLOC_NULL_MEM_OK) == 0)
+       png_error(png_ptr, "Out of Memory");
+   return (ret);

 }
 }

-png_voidp
-png_malloc_default(png_structp png_ptr, png_uint_32 size)
+
+png_voidp PNGAPI
+png_malloc_default(png_structp png_ptr, png_alloc_size_t size)

 {
    png_voidp ret;
 #endif /* PNG_USER_MEM_SUPPORTED */
 
 {
    png_voidp ret;
 #endif /* PNG_USER_MEM_SUPPORTED */
 

+   if (png_ptr == NULL || size == 0)
+      return (NULL);
+

 #ifdef PNG_MAX_MALLOC_64K
    if (size > (png_uint_32)65536L)
 #ifdef PNG_MAX_MALLOC_64K
    if (size > (png_uint_32)65536L)

-      png_error(png_ptr, "Cannot Allocate > 64K");
+   {
+#ifndef PNG_USER_MEM_SUPPORTED
+      if ((png_ptr->flags&PNG_FLAG_MALLOC_NULL_MEM_OK) == 0)
+         png_error(png_ptr, "Cannot Allocate > 64K");
+      else
+#endif
+         return NULL;
+   }

 #endif
 
 #endif
 

+   /* Check for overflow */

 #if defined(__TURBOC__) && !defined(__FLAT__)
 #if defined(__TURBOC__) && !defined(__FLAT__)

-   ret = farmalloc(size);
+   if (size != (unsigned long)size)
+      ret = NULL;
+   else
+      ret = farmalloc(size);

 #else
 # if defined(_MSC_VER) && defined(MAXSEG_64K)
 #else
 # if defined(_MSC_VER) && defined(MAXSEG_64K)

-   ret = halloc(size, 1);
+   if (size != (unsigned long)size)
+      ret = NULL;
+   else
+      ret = halloc(size, 1);

 # else
 # else

-   ret = malloc((size_t)size);
+   if (size != (size_t)size)
+      ret = NULL;
+   else
+      ret = malloc((size_t)size);

 # endif
 #endif
 
 # endif
 #endif
 

-   if (ret == NULL)
-   {
+#ifndef PNG_USER_MEM_SUPPORTED
+   if (ret == NULL && (png_ptr->flags&PNG_FLAG_MALLOC_NULL_MEM_OK) == 0)

       png_error(png_ptr, "Out of Memory");
       png_error(png_ptr, "Out of Memory");

-   }
+#endif

 
    return (ret);
 }
 
 /* Free a pointer allocated by png_malloc().  If ptr is NULL, return
 
    return (ret);
 }
 
 /* Free a pointer allocated by png_malloc().  If ptr is NULL, return

-   without taking any action. */
-void
+ * without taking any action.
+ */
+void PNGAPI

 png_free(png_structp png_ptr, png_voidp ptr)
 {
    if (png_ptr == NULL || ptr == NULL)
 png_free(png_structp png_ptr, png_voidp ptr)
 {
    if (png_ptr == NULL || ptr == NULL)


@@ -433,79 +533,79 @@ png_free(png_structp png_ptr, png_voidp ptr)
    if (png_ptr->free_fn != NULL)
    {
       (*(png_ptr->free_fn))(png_ptr, ptr);
    if (png_ptr->free_fn != NULL)
    {
       (*(png_ptr->free_fn))(png_ptr, ptr);

-      ptr = NULL;

       return;
    }
       return;
    }

-   else png_free_default(png_ptr, ptr);
+   else
+      png_free_default(png_ptr, ptr);

 }
 }

-void
+void PNGAPI

 png_free_default(png_structp png_ptr, png_voidp ptr)
 {
 png_free_default(png_structp png_ptr, png_voidp ptr)
 {

+   if (png_ptr == NULL || ptr == NULL)
+      return;
+

 #endif /* PNG_USER_MEM_SUPPORTED */
 
 #if defined(__TURBOC__) && !defined(__FLAT__)
    farfree(ptr);
 #endif /* PNG_USER_MEM_SUPPORTED */
 
 #if defined(__TURBOC__) && !defined(__FLAT__)
    farfree(ptr);

-   ptr = NULL;

 #else
 # if defined(_MSC_VER) && defined(MAXSEG_64K)
    hfree(ptr);
 #else
 # if defined(_MSC_VER) && defined(MAXSEG_64K)
    hfree(ptr);

-   ptr = NULL;

 # else
    free(ptr);
 # else
    free(ptr);

-   ptr = NULL;

 # endif
 #endif
 }
 
 #endif /* Not Borland DOS special memory handler */
 
 # endif
 #endif
 }
 
 #endif /* Not Borland DOS special memory handler */
 

-png_voidp
-png_memcpy_check (png_structp png_ptr, png_voidp s1, png_voidp s2,
-   png_uint_32 length)
+/* This function was added at libpng version 1.2.3.  The png_malloc_warn()
+ * function will set up png_malloc() to issue a png_warning and return NULL
+ * instead of issuing a png_error, if it fails to allocate the requested
+ * memory.
+ */
+png_voidp PNGAPI
+png_malloc_warn(png_structp png_ptr, png_alloc_size_t size)

 {
 {

-   png_size_t size;
-
-   size = (png_size_t)length;
-   if ((png_uint_32)size != length)
-      png_error(png_ptr,"Overflow in png_memcpy_check.");
-
-   return(png_memcpy (s1, s2, size));
+   png_voidp ptr;
+   png_uint_32 save_flags;
+   if (png_ptr == NULL)
+      return (NULL);
+
+   save_flags = png_ptr->flags;
+   png_ptr->flags|=PNG_FLAG_MALLOC_NULL_MEM_OK;
+   ptr = (png_voidp)png_malloc((png_structp)png_ptr, size);
+   png_ptr->flags=save_flags;
+   return(ptr);

 }
 
 }
 

-png_voidp
-png_memset_check (png_structp png_ptr, png_voidp s1, int value,
-   png_uint_32 length)
-{
-   png_size_t size;
-
-   size = (png_size_t)length;
-   if ((png_uint_32)size != length)
-      png_error(png_ptr,"Overflow in png_memset_check.");
-
-   return (png_memset (s1, value, size));
-
-}

 
 #ifdef PNG_USER_MEM_SUPPORTED
 /* This function is called when the application wants to use another method
  * of allocating and freeing memory.
  */
 
 #ifdef PNG_USER_MEM_SUPPORTED
 /* This function is called when the application wants to use another method
  * of allocating and freeing memory.
  */

-void
+void PNGAPI

 png_set_mem_fn(png_structp png_ptr, png_voidp mem_ptr, png_malloc_ptr
   malloc_fn, png_free_ptr free_fn)
 {
 png_set_mem_fn(png_structp png_ptr, png_voidp mem_ptr, png_malloc_ptr
   malloc_fn, png_free_ptr free_fn)
 {

-   png_ptr->mem_ptr = mem_ptr;
-   png_ptr->malloc_fn = malloc_fn;
-   png_ptr->free_fn = free_fn;
+   if (png_ptr != NULL)
+   {
+      png_ptr->mem_ptr = mem_ptr;
+      png_ptr->malloc_fn = malloc_fn;
+      png_ptr->free_fn = free_fn;
+   }

 }
 
 /* This function returns a pointer to the mem_ptr associated with the user
  * functions.  The application should free any memory associated with this
  * pointer before png_write_destroy and png_read_destroy are called.
  */
 }
 
 /* This function returns a pointer to the mem_ptr associated with the user
  * functions.  The application should free any memory associated with this
  * pointer before png_write_destroy and png_read_destroy are called.
  */

-png_voidp
+png_voidp PNGAPI

 png_get_mem_ptr(png_structp png_ptr)
 {
 png_get_mem_ptr(png_structp png_ptr)
 {

+   if (png_ptr == NULL)
+      return (NULL);

    return ((png_voidp)png_ptr->mem_ptr);
 }
 #endif /* PNG_USER_MEM_SUPPORTED */
    return ((png_voidp)png_ptr->mem_ptr);
 }
 #endif /* PNG_USER_MEM_SUPPORTED */

+#endif /* PNG_READ_SUPPORTED || PNG_WRITE_SUPPORTED */