diff options
Diffstat (limited to 'libpng/pngmem.c')
| -rw-r--r-- | libpng/pngmem.c | 517 |
1 files changed, 517 insertions, 0 deletions
diff --git a/libpng/pngmem.c b/libpng/pngmem.c new file mode 100644 index 0000000..b1741a4 --- /dev/null +++ b/libpng/pngmem.c @@ -0,0 +1,517 @@ + +/* pngmem.c - stub functions for memory allocation + * + * libpng 1.2.1 - December 12, 2001 + * For conditions of distribution and use, see copyright notice in png.h + * Copyright (c) 1998-2001 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 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" + +/* 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 /* PRIVATE */ +png_create_struct(int type) +{ +#ifdef PNG_USER_MEM_SUPPORTED + return (png_create_struct_2(type, png_malloc_ptr_NULL, png_voidp_NULL)); +} + +/* Alternate version of png_create_struct, for use with user-defined malloc. */ +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) + size = sizeof(png_info); + else if (type == PNG_STRUCT_PNG) + size = 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, (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, png_free_ptr_NULL, png_voidp_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_voidp PNGAPI +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 (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)); + if (ret == NULL) + png_error(png_ptr, "Out of memory!"); + return (ret); + } + else + return png_malloc_default(png_ptr, size); +} + +png_voidp PNGAPI +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"); +#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; + } + + 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)); + 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 = 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) + 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 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->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_voidp /* PRIVATE */ +png_create_struct(int type) +{ +#ifdef PNG_USER_MEM_SUPPORTED + return (png_create_struct_2(type, png_malloc_ptr_NULL, png_voidp_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 /* 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) + size = sizeof(png_info); + else if (type == PNG_STRUCT_PNG) + size = 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__) + 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 /* PRIVATE */ +png_destroy_struct(png_voidp struct_ptr) +{ +#ifdef PNG_USER_MEM_SUPPORTED + png_destroy_struct_2(struct_ptr, png_free_ptr_NULL, png_voidp_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_voidp PNGAPI +png_malloc(png_structp png_ptr, png_uint_32 size) +{ + 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, size)); + if (ret == NULL) + png_error(png_ptr, "Out of Memory!"); + return (ret); + } + else + return (png_malloc_default(png_ptr, size)); +} +png_voidp /* PRIVATE */ +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"); +#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(). 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 /* PRIVATE */ +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 */ + +png_voidp /* PRIVATE */ +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 /* PRIVATE */ +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. + */ +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_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_structp png_ptr) +{ + return ((png_voidp)png_ptr->mem_ptr); +} +#endif /* PNG_USER_MEM_SUPPORTED */ |