| |
| /* pngmem.c - stub functions for memory allocation |
| * |
| * Last changed in libpng 1.6.0 [(PENDING RELEASE)] |
| * 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) |
| /* 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 |
| } |
| |
| /* 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 */ |