/* pngmem.c - stub functions for memory allocation | |
* | |
* Last changed in libpng 1.5.4 [July 7, 2011] | |
* Copyright (c) 1998-2011 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 | |
* 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. | |
*/ | |
#include "pngpriv.h" | |
#if defined(PNG_READ_SUPPORTED) || defined(PNG_WRITE_SUPPORTED) | |
/* 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 */ | |
/* 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_FUNCTION(png_voidp /* PRIVATE */, | |
png_create_struct,(int type),PNG_ALLOCATED) | |
{ | |
# ifdef PNG_USER_MEM_SUPPORTED | |
return (png_create_struct_2(type, NULL, NULL)); | |
} | |
/* Alternate version of png_create_struct, for use with user-defined malloc. */ | |
PNG_FUNCTION(png_voidp /* PRIVATE */, | |
png_create_struct_2,(int type, png_malloc_ptr malloc_fn, png_voidp mem_ptr), | |
PNG_ALLOCATED) | |
{ | |
# endif /* PNG_USER_MEM_SUPPORTED */ | |
png_size_t size; | |
png_voidp struct_ptr; | |
if (type == PNG_STRUCT_INFO) | |
size = png_sizeof(png_info); | |
else if (type == PNG_STRUCT_PNG) | |
size = png_sizeof(png_struct); | |
else | |
return (png_get_copyright(NULL)); | |
# ifdef PNG_USER_MEM_SUPPORTED | |
if (malloc_fn != NULL) | |
{ | |
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 */ | |
struct_ptr = (png_voidp)farmalloc(size); | |
if (struct_ptr != NULL) | |
png_memset(struct_ptr, 0, size); | |
return (struct_ptr); | |
} | |
/* Free memory allocated by a png_create_struct() call */ | |
void /* PRIVATE */ | |
png_destroy_struct(png_voidp struct_ptr) | |
{ | |
# ifdef PNG_USER_MEM_SUPPORTED | |
png_destroy_struct_2(struct_ptr, NULL, NULL); | |
} | |
/* Free memory allocated by a png_create_struct() call */ | |
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 | |
if (free_fn != NULL) | |
{ | |
png_struct dummy_struct; | |
png_structp png_ptr = &dummy_struct; | |
png_ptr->mem_ptr=mem_ptr; | |
(*(free_fn))(png_ptr, struct_ptr); | |
return; | |
} | |
# endif /* PNG_USER_MEM_SUPPORTED */ | |
farfree (struct_ptr); | |
} | |
} | |
/* 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. | |
* | |
* 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 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 | |
* been updated by Alexander Lehmann for version 0.89 to waste less | |
* memory. | |
* | |
* Note that we can't use png_size_t for the "size" declaration, | |
* since on some systems a png_size_t is a 16-bit quantity, and as a | |
* result, we would be truncating potentially larger memory requests | |
* (which should cause a fatal error) and introducing major problems. | |
*/ | |
PNG_FUNCTION(png_voidp,PNGAPI | |
png_calloc,(png_structp png_ptr, png_alloc_size_t size),PNG_ALLOCATED) | |
{ | |
png_voidp ret; | |
ret = (png_malloc(png_ptr, size)); | |
if (ret != NULL) | |
png_memset(ret,0,(png_size_t)size); | |
return (ret); | |
} | |
PNG_FUNCTION(png_voidp,PNGAPI | |
png_malloc,(png_structp png_ptr, png_alloc_size_t size),PNG_ALLOCATED) | |
{ | |
png_voidp ret; | |
if (png_ptr == NULL || size == 0) | |
return (NULL); | |
# ifdef PNG_USER_MEM_SUPPORTED | |
if (png_ptr->malloc_fn != NULL) | |
ret = ((png_voidp)(*(png_ptr->malloc_fn))(png_ptr, (png_size_t)size)); | |
else | |
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_FUNCTION(png_voidp,PNGAPI | |
png_malloc_default,(png_structp png_ptr, png_alloc_size_t size),PNG_ALLOCATED) | |
{ | |
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) | |
{ | |
png_warning(png_ptr, "Cannot Allocate > 64K"); | |
ret = NULL; | |
} | |
else | |
# endif | |
if (size != (size_t)size) | |
ret = NULL; | |
else if (size == (png_uint_32)65536L) | |
{ | |
if (png_ptr->offset_table == NULL) | |
{ | |
/* Try to see if we need to do any of this fancy stuff */ | |
ret = farmalloc(size); | |
if (ret == NULL || ((png_size_t)ret & 0xffff)) | |
{ | |
int num_blocks; | |
png_uint_32 total_size; | |
png_bytep table; | |
int i, mem_level, window_bits; | |
png_byte huge * hptr; | |
int window_bits | |
if (ret != NULL) | |
{ | |
farfree(ret); | |
ret = NULL; | |
} | |
window_bits = | |
png_ptr->zlib_window_bits >= png_ptr->zlib_text_window_bits ? | |
png_ptr->zlib_window_bits : png_ptr->zlib_text_window_bits; | |
if (window_bits > 14) | |
num_blocks = (int)(1 << (window_bits - 14)); | |
else | |
num_blocks = 1; | |
mem_level = | |
png_ptr->zlib_mem_level >= png_ptr->zlib_text_mem_level ? | |
png_ptr->zlib_mem_level : png_ptr->zlib_text_mem_level; | |
if (mem_level >= 7) | |
num_blocks += (int)(1 << (mem_level - 7)); | |
else | |
num_blocks++; | |
total_size = ((png_uint_32)65536L) * (png_uint_32)num_blocks+16; | |
table = farmalloc(total_size); | |
if (table == NULL) | |
{ | |
# 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) | |
{ | |
# 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_sizeof(png_bytep)); | |
if (png_ptr->offset_table_ptr == NULL) | |
{ | |
# 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 = 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; | |
hptr = hptr + (png_uint_32)65536L; /* "+=" fails on TC++3.0 */ | |
} | |
png_ptr->offset_table_number = num_blocks; | |
png_ptr->offset_table_count = 0; | |
png_ptr->offset_table_count_free = 0; | |
} | |
} | |
if (png_ptr->offset_table_count >= png_ptr->offset_table_number) | |
{ | |
# 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); | |
# ifndef PNG_USER_MEM_SUPPORTED | |
if (ret == NULL) | |
{ | |
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); | |
} | |
/* 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) | |
return; | |
# ifdef PNG_USER_MEM_SUPPORTED | |
if (png_ptr->free_fn != NULL) | |
{ | |
(*(png_ptr->free_fn))(png_ptr, ptr); | |
return; | |
} | |
else | |
png_free_default(png_ptr, ptr); | |
} | |
void PNGAPI | |
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; | |
for (i = 0; i < png_ptr->offset_table_count; i++) | |
{ | |
if (ptr == png_ptr->offset_table_ptr[i]) | |
{ | |
ptr = NULL; | |
png_ptr->offset_table_count_free++; | |
break; | |
} | |
} | |
if (png_ptr->offset_table_count_free == png_ptr->offset_table_count) | |
{ | |
farfree(png_ptr->offset_table); | |
farfree(png_ptr->offset_table_ptr); | |
png_ptr->offset_table = NULL; | |
png_ptr->offset_table_ptr = NULL; | |
} | |
} | |
if (ptr != NULL) | |
farfree(ptr); | |
} | |
#else /* Not the Borland DOS special memory handler */ | |
/* 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_FUNCTION(png_voidp /* PRIVATE */, | |
png_create_struct,(int type),PNG_ALLOCATED) | |
{ | |
# ifdef PNG_USER_MEM_SUPPORTED | |
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 | |
to improve performance noticably. */ | |
PNG_FUNCTION(png_voidp /* PRIVATE */, | |
png_create_struct_2,(int type, png_malloc_ptr malloc_fn, png_voidp mem_ptr), | |
PNG_ALLOCATED) | |
{ | |
# endif /* PNG_USER_MEM_SUPPORTED */ | |
png_size_t size; | |
png_voidp struct_ptr; | |
if (type == PNG_STRUCT_INFO) | |
size = png_sizeof(png_info); | |
else if (type == PNG_STRUCT_PNG) | |
size = png_sizeof(png_struct); | |
else | |
return (NULL); | |
# ifdef PNG_USER_MEM_SUPPORTED | |
if (malloc_fn != 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__) | |
struct_ptr = (png_voidp)farmalloc(size); | |
# else | |
# if defined(_MSC_VER) && defined(MAXSEG_64K) | |
struct_ptr = (png_voidp)halloc(size, 1); | |
# else | |
struct_ptr = (png_voidp)malloc(size); | |
# endif | |
# endif | |
if (struct_ptr != NULL) | |
png_memset(struct_ptr, 0, size); | |
return (struct_ptr); | |
} | |
/* Free memory allocated by a png_create_struct() call */ | |
void /* PRIVATE */ | |
png_destroy_struct(png_voidp struct_ptr) | |
{ | |
# ifdef PNG_USER_MEM_SUPPORTED | |
png_destroy_struct_2(struct_ptr, NULL, NULL); | |
} | |
/* Free memory allocated by a png_create_struct() call */ | |
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 | |
if (free_fn != NULL) | |
{ | |
png_struct dummy_struct; | |
png_structp png_ptr = &dummy_struct; | |
png_ptr->mem_ptr=mem_ptr; | |
(*(free_fn))(png_ptr, struct_ptr); | |
return; | |
} | |
# endif /* PNG_USER_MEM_SUPPORTED */ | |
# if defined(__TURBOC__) && !defined(__FLAT__) | |
farfree(struct_ptr); | |
# else | |
# if defined(_MSC_VER) && defined(MAXSEG_64K) | |
hfree(struct_ptr); | |
# else | |
free(struct_ptr); | |
# endif | |
# endif | |
} | |
} | |
/* 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. | |
*/ | |
PNG_FUNCTION(png_voidp,PNGAPI | |
png_calloc,(png_structp png_ptr, png_alloc_size_t size),PNG_ALLOCATED) | |
{ | |
png_voidp ret; | |
ret = (png_malloc(png_ptr, size)); | |
if (ret != NULL) | |
png_memset(ret,0,(png_size_t)size); | |
return (ret); | |
} | |
PNG_FUNCTION(png_voidp,PNGAPI | |
png_malloc,(png_structp png_ptr, png_alloc_size_t size),PNG_ALLOCATED) | |
{ | |
png_voidp ret; | |
# ifdef PNG_USER_MEM_SUPPORTED | |
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 | |
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_FUNCTION(png_voidp,PNGAPI | |
png_malloc_default,(png_structp png_ptr, png_alloc_size_t size),PNG_ALLOCATED) | |
{ | |
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) | |
{ | |
# 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 | |
/* Check for overflow */ | |
# if defined(__TURBOC__) && !defined(__FLAT__) | |
if (size != (unsigned long)size) | |
ret = NULL; | |
else | |
ret = farmalloc(size); | |
# else | |
# if defined(_MSC_VER) && defined(MAXSEG_64K) | |
if (size != (unsigned long)size) | |
ret = NULL; | |
else | |
ret = halloc(size, 1); | |
# else | |
if (size != (size_t)size) | |
ret = NULL; | |
else | |
ret = malloc((size_t)size); | |
# endif | |
# endif | |
# 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"); | |
# endif | |
return (ret); | |
} | |
/* Free a pointer allocated by png_malloc(). 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) | |
return; | |
# ifdef PNG_USER_MEM_SUPPORTED | |
if (png_ptr->free_fn != NULL) | |
{ | |
(*(png_ptr->free_fn))(png_ptr, ptr); | |
return; | |
} | |
else | |
png_free_default(png_ptr, ptr); | |
} | |
void PNGAPI | |
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); | |
# else | |
# if defined(_MSC_VER) && defined(MAXSEG_64K) | |
hfree(ptr); | |
# else | |
free(ptr); | |
# endif | |
# endif | |
} | |
#endif /* Not Borland DOS special memory handler */ | |
/* 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_FUNCTION(png_voidp,PNGAPI | |
png_malloc_warn,(png_structp png_ptr, png_alloc_size_t size),PNG_ALLOCATED) | |
{ | |
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); | |
} | |
#ifdef PNG_USER_MEM_SUPPORTED | |
/* This function is called when the application wants to use another method | |
* of allocating and freeing memory. | |
*/ | |
void PNGAPI | |
png_set_mem_fn(png_structp png_ptr, png_voidp mem_ptr, png_malloc_ptr | |
malloc_fn, png_free_ptr 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. | |
*/ | |
png_voidp PNGAPI | |
png_get_mem_ptr(png_const_structp png_ptr) | |
{ | |
if (png_ptr == NULL) | |
return (NULL); | |
return ((png_voidp)png_ptr->mem_ptr); | |
} | |
#endif /* PNG_USER_MEM_SUPPORTED */ | |
#endif /* PNG_READ_SUPPORTED || PNG_WRITE_SUPPORTED */ |