/* pngmem.c - stub functions for memory allocation
*
- * libpng 1.0.1
+ * 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, Glenn Randers-Pehrson
- * March 15, 1998
+ * Copyright (c) 1998, 1999 Glenn Randers-Pehrson
*
- * This file provides a location for all memory allocation. Users which
- * need special memory handling are expected to modify the code in this file
- * to meet their needs. See the instructions at each function.
+ * This file provides a location for all memory allocation. Users who
+ * need special memory handling are expected to supply replacement
+ * functions for png_malloc() and png_free(), and to use
+ * png_create_read_struct_2() and png_create_write_struct_2() to
+ * identify the replacement functions.
*/
#define PNG_INTERNAL
#include "png.h"
-/* The following "hides" PNG_MALLOC and PNG_FREE thus allowing the pngtest
- application to put a wrapper on top of them. */
-#ifdef PNGTEST_MEMORY_DEBUG
-#define PNG_MALLOC png_debug_malloc
-#define PNG_FREE png_debug_free
-#else
-#define PNG_MALLOC png_malloc
-#define PNG_FREE png_free
-#endif
-
/* 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 */
png_voidp
png_create_struct(int type)
{
+#ifdef PNG_USER_MEM_SUPPORTED
+ return (png_create_struct_2(type, NULL));
+}
+
+/* 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)
+{
+#endif /* PNG_USER_MEM_SUPPORTED */
png_size_t size;
png_voidp struct_ptr;
else
return ((png_voidp)NULL);
+#ifdef PNG_USER_MEM_SUPPORTED
+ if(malloc_fn != NULL)
+ {
+ if ((struct_ptr = (*(malloc_fn))(NULL, size)) != NULL)
+ png_memset(struct_ptr, 0, size);
+ return (struct_ptr);
+ }
+#endif /* PNG_USER_MEM_SUPPORTED */
if ((struct_ptr = (png_voidp)farmalloc(size)) != NULL)
{
png_memset(struct_ptr, 0, size);
}
-
return (struct_ptr);
}
void
png_destroy_struct(png_voidp struct_ptr)
{
+#ifdef PNG_USER_MEM_SUPPORTED
+ png_destroy_struct_2(struct_ptr, (png_free_ptr)NULL);
+}
+
+/* Free memory allocated by a png_create_struct() call */
+void
+png_destroy_struct_2(png_voidp struct_ptr, png_free_ptr free_fn)
+{
+#endif
if (struct_ptr != NULL)
{
+#ifdef PNG_USER_MEM_SUPPORTED
+ if(free_fn != NULL)
+ {
+ png_struct dummy_struct;
+ png_structp png_ptr = &dummy_struct;
+ (*(free_fn))(png_ptr, struct_ptr);
+ struct_ptr = NULL;
+ return;
+ }
+#endif /* PNG_USER_MEM_SUPPORTED */
farfree (struct_ptr);
struct_ptr = NULL;
}
* have the ability to do that.
*
* Borland seems to have a problem in DOS mode for exactly 64K.
- * It gives you a segment with an offset of 8 (perhaps to store it's
+ * It gives you a segment with an offset of 8 (perhaps to store its
* memory stuff). zlib doesn't like this at all, so we have to
* detect and deal with it. This code should not be needed in
* Windows or OS/2 modes, and only in 16 bit mode. This code has
* (which should cause a fatal error) and introducing major problems.
*/
png_voidp
-PNG_MALLOC(png_structp png_ptr, png_uint_32 size)
+png_malloc(png_structp png_ptr, png_uint_32 size)
{
+#ifndef PNG_USER_MEM_SUPPORTED
png_voidp ret;
+#endif
if (png_ptr == NULL || size == 0)
return ((png_voidp)NULL);
+#ifdef PNG_USER_MEM_SUPPORTED
+ if(png_ptr->malloc_fn != NULL)
+ return ((png_voidp)(*(png_ptr->malloc_fn))(png_ptr, size));
+ else
+ return png_malloc_default(png_ptr, size);
+}
+
+png_voidp
+png_malloc_default(png_structp png_ptr, png_uint_32 size)
+{
+ png_voidp ret;
+#endif /* PNG_USER_MEM_SUPPORTED */
+
#ifdef PNG_MAX_MALLOC_64K
if (size > (png_uint_32)65536L)
png_error(png_ptr, "Cannot Allocate > 64K");
return (ret);
}
-/* free a pointer allocated by PNG_MALLOC(). In the default
+/* 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
-PNG_FREE(png_structp png_ptr, png_voidp ptr)
+png_free(png_structp png_ptr, png_voidp ptr)
{
if (png_ptr == NULL || ptr == NULL)
return;
+#ifdef PNG_USER_MEM_SUPPORTED
+ if (png_ptr->free_fn != NULL)
+ {
+ (*(png_ptr->free_fn))(png_ptr, ptr);
+ ptr = NULL;
+ return;
+ }
+ else png_free_default(png_ptr, ptr);
+}
+
+void
+png_free_default(png_structp png_ptr, png_voidp ptr)
+{
+#endif /* PNG_USER_MEM_SUPPORTED */
+
if (png_ptr->offset_table != NULL)
{
int i;
png_voidp
png_create_struct(int type)
{
+#ifdef PNG_USER_MEM_SUPPORTED
+ return (png_create_struct_2(type, 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
+ to improve performance noticably.*/
+png_voidp
+png_create_struct_2(int type, png_malloc_ptr malloc_fn)
+{
+#endif /* PNG_USER_MEM_SUPPORTED */
png_size_t size;
png_voidp struct_ptr;
else
return ((png_voidp)NULL);
+#ifdef PNG_USER_MEM_SUPPORTED
+ if(malloc_fn != NULL)
+ {
+ if ((struct_ptr = (*(malloc_fn))(NULL, size)) != NULL)
+ 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)
#else
void
png_destroy_struct(png_voidp struct_ptr)
{
+#ifdef PNG_USER_MEM_SUPPORTED
+ png_destroy_struct_2(struct_ptr, (png_free_ptr)NULL);
+}
+
+/* Free memory allocated by a png_create_struct() call */
+void
+png_destroy_struct_2(png_voidp struct_ptr, png_free_ptr free_fn)
+{
+#endif /* PNG_USER_MEM_SUPPORTED */
if (struct_ptr != NULL)
{
+#ifdef PNG_USER_MEM_SUPPORTED
+ if(free_fn != NULL)
+ {
+ png_struct dummy_struct;
+ png_structp png_ptr = &dummy_struct;
+ (*(free_fn))(png_ptr, struct_ptr);
+ struct_ptr = NULL;
+ 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);
+ struct_ptr = NULL;
# else
free(struct_ptr);
+ struct_ptr = NULL;
# endif
#endif
}
have the ability to do that. */
png_voidp
-PNG_MALLOC(png_structp png_ptr, png_uint_32 size)
+png_malloc(png_structp png_ptr, png_uint_32 size)
{
+#ifndef PNG_USER_MEM_SUPPORTED
png_voidp ret;
-
+#endif
if (png_ptr == NULL || size == 0)
return ((png_voidp)NULL);
+#ifdef PNG_USER_MEM_SUPPORTED
+ if(png_ptr->malloc_fn != NULL)
+ return ((png_voidp)(*(png_ptr->malloc_fn))(png_ptr, size));
+ else
+ return (png_malloc_default(png_ptr, size));
+}
+png_voidp
+png_malloc_default(png_structp png_ptr, png_uint_32 size)
+{
+ png_voidp ret;
+#endif /* PNG_USER_MEM_SUPPORTED */
+
#ifdef PNG_MAX_MALLOC_64K
if (size > (png_uint_32)65536L)
png_error(png_ptr, "Cannot Allocate > 64K");
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. */
+/* Free a pointer allocated by png_malloc(). If ptr is NULL, return
+ without taking any action. */
void
-PNG_FREE(png_structp png_ptr, png_voidp ptr)
+png_free(png_structp png_ptr, png_voidp ptr)
{
if (png_ptr == NULL || ptr == NULL)
return;
+#ifdef PNG_USER_MEM_SUPPORTED
+ if (png_ptr->free_fn != NULL)
+ {
+ (*(png_ptr->free_fn))(png_ptr, ptr);
+ ptr = NULL;
+ return;
+ }
+ else png_free_default(png_ptr, ptr);
+}
+void
+png_free_default(png_structp png_ptr, png_voidp 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);
+ ptr = NULL;
# else
free(ptr);
+ ptr = NULL;
# endif
#endif
}
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));
}
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.
+ */
+void
+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;
+}
+
+/* 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_get_mem_ptr(png_structp png_ptr)
+{
+ return ((png_voidp)png_ptr->mem_ptr);
+}
+#endif /* PNG_USER_MEM_SUPPORTED */
projects / wxWidgets.git / blobdiff