| |
| /* pngmem.c - stub functions for memory allocation |
| * |
| * libpng 1.0.1a |
| * 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 |
| * April 21, 1998 |
| * |
| * This file provides a location for all memory allocation. Users who |
| * need special memory handling are expected to modify the code in this file |
| * to meet their needs. See the instructions at each function. |
| */ |
| |
| #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 */ |
| |
| /* 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_create_struct(int type) |
| { |
| png_size_t size; |
| png_voidp struct_ptr; |
| |
| if (type == PNG_STRUCT_INFO) |
| size = sizeof(png_info); |
| else if (type == PNG_STRUCT_PNG) |
| size = sizeof(png_struct); |
| else |
| return ((png_voidp)NULL); |
| |
| if ((struct_ptr = (png_voidp)farmalloc(size)) != NULL) |
| { |
| png_memset(struct_ptr, 0, size); |
| } |
| |
| return (struct_ptr); |
| } |
| |
| |
| /* Free memory allocated by a png_create_struct() call */ |
| void |
| png_destroy_struct(png_voidp struct_ptr) |
| { |
| if (struct_ptr != NULL) |
| { |
| farfree (struct_ptr); |
| struct_ptr = NULL; |
| } |
| } |
| |
| /* 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 it's |
| * 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_voidp |
| PNG_MALLOC(png_structp png_ptr, png_uint_32 size) |
| { |
| png_voidp ret; |
| if (png_ptr == NULL || size == 0) |
| return ((png_voidp)NULL); |
| |
| #ifdef PNG_MAX_MALLOC_64K |
| if (size > (png_uint_32)65536L) |
| png_error(png_ptr, "Cannot Allocate > 64K"); |
| #endif |
| |
| 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; |
| png_byte huge * hptr; |
| |
| if (ret != NULL) |
| { |
| farfree(ret); |
| ret = NULL; |
| } |
| |
| num_blocks = (int)(1 << (png_ptr->zlib_window_bits - 14)); |
| if (num_blocks < 1) |
| num_blocks = 1; |
| if (png_ptr->zlib_mem_level >= 7) |
| num_blocks += (int)(1 << (png_ptr->zlib_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) |
| { |
| png_error(png_ptr, "Out Of Memory."); /* Note "O" and "M" */ |
| } |
| |
| if ((png_size_t)table & 0xfff0) |
| { |
| png_error(png_ptr, "Farmalloc didn't return normalized pointer"); |
| } |
| |
| png_ptr->offset_table = table; |
| png_ptr->offset_table_ptr = farmalloc(num_blocks * |
| sizeof (png_bytep)); |
| |
| if (png_ptr->offset_table_ptr == NULL) |
| { |
| png_error(png_ptr, "Out Of memory."); |
| } |
| |
| hptr = (png_byte huge *)table; |
| if ((png_size_t)hptr & 0xf) |
| { |
| hptr = (png_byte huge *)((long)(hptr) & 0xfffffff0L); |
| hptr += 16L; |
| } |
| for (i = 0; i < num_blocks; i++) |
| { |
| png_ptr->offset_table_ptr[i] = (png_bytep)hptr; |
| hptr += (png_uint_32)65536L; |
| } |
| |
| 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) |
| png_error(png_ptr, "Out of Memory."); |
| |
| ret = png_ptr->offset_table_ptr[png_ptr->offset_table_count++]; |
| } |
| else |
| ret = farmalloc(size); |
| |
| if (ret == NULL) |
| { |
| png_error(png_ptr, "Out of memory."); /* Note "o" and "m" */ |
| } |
| |
| 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 |
| PNG_FREE(png_structp png_ptr, png_voidp ptr) |
| { |
| 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); |
| ptr = NULL; |
| } |
| } |
| |
| #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_voidp |
| png_create_struct(int type) |
| { |
| png_size_t size; |
| png_voidp struct_ptr; |
| |
| if (type == PNG_STRUCT_INFO) |
| size = sizeof(png_info); |
| else if (type == PNG_STRUCT_PNG) |
| size = sizeof(png_struct); |
| else |
| return ((png_voidp)NULL); |
| |
| #if defined(__TURBOC__) && !defined(__FLAT__) |
| if ((struct_ptr = (png_voidp)farmalloc(size)) != NULL) |
| #else |
| # if defined(_MSC_VER) && defined(MAXSEG_64K) |
| if ((struct_ptr = (png_voidp)halloc(size,1)) != NULL) |
| # else |
| if ((struct_ptr = (png_voidp)malloc(size)) != NULL) |
| # endif |
| #endif |
| { |
| png_memset(struct_ptr, 0, size); |
| } |
| |
| return (struct_ptr); |
| } |
| |
| |
| /* Free memory allocated by a png_create_struct() call */ |
| void |
| png_destroy_struct(png_voidp struct_ptr) |
| { |
| if (struct_ptr != NULL) |
| { |
| #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_voidp |
| PNG_MALLOC(png_structp png_ptr, png_uint_32 size) |
| { |
| png_voidp ret; |
| |
| if (png_ptr == NULL || size == 0) |
| return ((png_voidp)NULL); |
| |
| #ifdef PNG_MAX_MALLOC_64K |
| if (size > (png_uint_32)65536L) |
| png_error(png_ptr, "Cannot Allocate > 64K"); |
| #endif |
| |
| #if defined(__TURBOC__) && !defined(__FLAT__) |
| ret = farmalloc(size); |
| #else |
| # if defined(_MSC_VER) && defined(MAXSEG_64K) |
| ret = halloc(size, 1); |
| # else |
| ret = malloc((size_t)size); |
| # endif |
| #endif |
| |
| if (ret == NULL) |
| { |
| png_error(png_ptr, "Out of Memory"); |
| } |
| |
| 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 |
| PNG_FREE(png_structp png_ptr, png_voidp ptr) |
| { |
| if (png_ptr == NULL || ptr == NULL) |
| return; |
| |
| #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 */ |
| |
| png_voidp |
| png_memcpy_check (png_structp png_ptr, png_voidp s1, png_voidp s2, |
| 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_memcpy_check."); |
| |
| return(png_memcpy (s1, s2, size)); |
| } |
| |
| 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)); |
| |
| } |