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			612 lines
		
	
	
		
			16 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			612 lines
		
	
	
		
			16 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| 
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| /* pngmem.c - stub functions for memory allocation
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|  *
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|  * Last changed in libpng 1.4.6 [April 8, 2011]
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|  * Copyright (c) 1998-2011 Glenn Randers-Pehrson
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|  * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
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|  * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
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|  *
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|  * This code is released under the libpng license.
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|  * For conditions of distribution and use, see the disclaimer
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|  * and license in png.h
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|  *
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|  * This file provides a location for all memory allocation.  Users who
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|  * need special memory handling are expected to supply replacement
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|  * functions for png_malloc() and png_free(), and to use
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|  * png_create_read_struct_2() and png_create_write_struct_2() to
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|  * identify the replacement functions.
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|  */
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| 
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| #define PNG_NO_PEDANTIC_WARNINGS
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| #include "png.h"
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| #if defined(PNG_READ_SUPPORTED) || defined(PNG_WRITE_SUPPORTED)
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| #include "pngpriv.h"
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| 
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| /* Borland DOS special memory handler */
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| #if defined(__TURBOC__) && !defined(_Windows) && !defined(__FLAT__)
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| /* If you change this, be sure to change the one in png.h also */
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| 
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| /* Allocate memory for a png_struct.  The malloc and memset can be replaced
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|    by a single call to calloc() if this is thought to improve performance. */
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| png_voidp /* PRIVATE */
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| png_create_struct(int type)
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| {
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| #ifdef PNG_USER_MEM_SUPPORTED
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|    return (png_create_struct_2(type, NULL, NULL));
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| }
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| 
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| /* Alternate version of png_create_struct, for use with user-defined malloc. */
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| png_voidp /* PRIVATE */
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| png_create_struct_2(int type, png_malloc_ptr malloc_fn, png_voidp mem_ptr)
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| {
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| #endif /* PNG_USER_MEM_SUPPORTED */
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|    png_size_t size;
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|    png_voidp struct_ptr;
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| 
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|    if (type == PNG_STRUCT_INFO)
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|       size = png_sizeof(png_info);
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|    else if (type == PNG_STRUCT_PNG)
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|       size = png_sizeof(png_struct);
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|    else
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|       return (png_get_copyright(NULL));
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| 
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| #ifdef PNG_USER_MEM_SUPPORTED
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|    if (malloc_fn != NULL)
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|    {
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|       png_struct dummy_struct;
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|       png_structp png_ptr = &dummy_struct;
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|       png_ptr->mem_ptr=mem_ptr;
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|       struct_ptr = (*(malloc_fn))(png_ptr, (png_uint_32)size);
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|    }
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|    else
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| #endif /* PNG_USER_MEM_SUPPORTED */
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|    struct_ptr = (png_voidp)farmalloc(size);
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|    if (struct_ptr != NULL)
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|       png_memset(struct_ptr, 0, size);
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|    return (struct_ptr);
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| }
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| 
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| /* Free memory allocated by a png_create_struct() call */
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| void /* PRIVATE */
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| png_destroy_struct(png_voidp struct_ptr)
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| {
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| #ifdef PNG_USER_MEM_SUPPORTED
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|    png_destroy_struct_2(struct_ptr, NULL, NULL);
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| }
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| 
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| /* Free memory allocated by a png_create_struct() call */
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| void /* PRIVATE */
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| png_destroy_struct_2(png_voidp struct_ptr, png_free_ptr free_fn,
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|     png_voidp mem_ptr)
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| {
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| #endif
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|    if (struct_ptr != NULL)
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|    {
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| #ifdef PNG_USER_MEM_SUPPORTED
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|       if (free_fn != NULL)
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|       {
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|          png_struct dummy_struct;
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|          png_structp png_ptr = &dummy_struct;
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|          png_ptr->mem_ptr=mem_ptr;
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|          (*(free_fn))(png_ptr, struct_ptr);
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|          return;
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|       }
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| #endif /* PNG_USER_MEM_SUPPORTED */
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|       farfree (struct_ptr);
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|    }
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| }
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| 
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| /* Allocate memory.  For reasonable files, size should never exceed
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|  * 64K.  However, zlib may allocate more then 64K if you don't tell
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|  * it not to.  See zconf.h and png.h for more information. zlib does
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|  * need to allocate exactly 64K, so whatever you call here must
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|  * have the ability to do that.
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|  *
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|  * Borland seems to have a problem in DOS mode for exactly 64K.
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|  * It gives you a segment with an offset of 8 (perhaps to store its
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|  * memory stuff).  zlib doesn't like this at all, so we have to
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|  * detect and deal with it.  This code should not be needed in
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|  * Windows or OS/2 modes, and only in 16 bit mode.  This code has
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|  * been updated by Alexander Lehmann for version 0.89 to waste less
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|  * memory.
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|  *
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|  * Note that we can't use png_size_t for the "size" declaration,
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|  * since on some systems a png_size_t is a 16-bit quantity, and as a
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|  * result, we would be truncating potentially larger memory requests
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|  * (which should cause a fatal error) and introducing major problems.
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|  */
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| png_voidp PNGAPI
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| png_calloc(png_structp png_ptr, png_alloc_size_t size)
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| {
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|    png_voidp ret;
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| 
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|    ret = (png_malloc(png_ptr, size));
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|    if (ret != NULL)
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|       png_memset(ret,0,(png_size_t)size);
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|    return (ret);
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| }
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| 
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| png_voidp PNGAPI
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| png_malloc(png_structp png_ptr, png_alloc_size_t size)
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| {
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|    png_voidp ret;
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| 
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|    if (png_ptr == NULL || size == 0)
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|       return (NULL);
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| 
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| #ifdef PNG_USER_MEM_SUPPORTED
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|    if (png_ptr->malloc_fn != NULL)
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|       ret = ((png_voidp)(*(png_ptr->malloc_fn))(png_ptr, (png_size_t)size));
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|    else
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|       ret = (png_malloc_default(png_ptr, size));
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|    if (ret == NULL && (png_ptr->flags&PNG_FLAG_MALLOC_NULL_MEM_OK) == 0)
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|        png_error(png_ptr, "Out of memory");
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|    return (ret);
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| }
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| 
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| png_voidp PNGAPI
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| png_malloc_default(png_structp png_ptr, png_alloc_size_t size)
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| {
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|    png_voidp ret;
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| #endif /* PNG_USER_MEM_SUPPORTED */
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| 
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|    if (png_ptr == NULL || size == 0)
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|       return (NULL);
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| 
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| #ifdef PNG_MAX_MALLOC_64K
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|    if (size > (png_uint_32)65536L)
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|    {
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|       png_warning(png_ptr, "Cannot Allocate > 64K");
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|       ret = NULL;
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|    }
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|    else
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| #endif
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| 
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|    if (size != (size_t)size)
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|       ret = NULL;
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|    else if (size == (png_uint_32)65536L)
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|    {
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|       if (png_ptr->offset_table == NULL)
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|       {
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|          /* Try to see if we need to do any of this fancy stuff */
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|          ret = farmalloc(size);
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|          if (ret == NULL || ((png_size_t)ret & 0xffff))
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|          {
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|             int num_blocks;
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|             png_uint_32 total_size;
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|             png_bytep table;
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|             int i;
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|             png_byte huge * hptr;
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| 
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|             if (ret != NULL)
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|             {
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|                farfree(ret);
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|                ret = NULL;
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|             }
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| 
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|             if (png_ptr->zlib_window_bits > 14)
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|                num_blocks = (int)(1 << (png_ptr->zlib_window_bits - 14));
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|             else
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|                num_blocks = 1;
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|             if (png_ptr->zlib_mem_level >= 7)
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|                num_blocks += (int)(1 << (png_ptr->zlib_mem_level - 7));
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|             else
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|                num_blocks++;
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| 
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|             total_size = ((png_uint_32)65536L) * (png_uint_32)num_blocks+16;
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| 
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|             table = farmalloc(total_size);
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| 
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|             if (table == NULL)
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|             {
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| #ifndef PNG_USER_MEM_SUPPORTED
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|                if ((png_ptr->flags&PNG_FLAG_MALLOC_NULL_MEM_OK) == 0)
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|                   png_error(png_ptr, "Out Of Memory"); /* Note "O", "M" */
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|                else
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|                   png_warning(png_ptr, "Out Of Memory");
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| #endif
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|                return (NULL);
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|             }
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| 
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|             if ((png_size_t)table & 0xfff0)
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|             {
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| #ifndef PNG_USER_MEM_SUPPORTED
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|                if ((png_ptr->flags&PNG_FLAG_MALLOC_NULL_MEM_OK) == 0)
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|                   png_error(png_ptr,
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|                     "Farmalloc didn't return normalized pointer");
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|                else
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|                   png_warning(png_ptr,
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|                     "Farmalloc didn't return normalized pointer");
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| #endif
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|                return (NULL);
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|             }
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| 
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|             png_ptr->offset_table = table;
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|             png_ptr->offset_table_ptr = farmalloc(num_blocks *
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|                png_sizeof(png_bytep));
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| 
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|             if (png_ptr->offset_table_ptr == NULL)
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|             {
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| #ifndef PNG_USER_MEM_SUPPORTED
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|                if ((png_ptr->flags&PNG_FLAG_MALLOC_NULL_MEM_OK) == 0)
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|                   png_error(png_ptr, "Out Of memory"); /* Note "O", "m" */
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|                else
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|                   png_warning(png_ptr, "Out Of memory");
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| #endif
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|                return (NULL);
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|             }
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| 
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|             hptr = (png_byte huge *)table;
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|             if ((png_size_t)hptr & 0xf)
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|             {
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|                hptr = (png_byte huge *)((long)(hptr) & 0xfffffff0L);
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|                hptr = hptr + 16L;  /* "hptr += 16L" fails on Turbo C++ 3.0 */
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|             }
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|             for (i = 0; i < num_blocks; i++)
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|             {
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|                png_ptr->offset_table_ptr[i] = (png_bytep)hptr;
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|                hptr = hptr + (png_uint_32)65536L;  /* "+=" fails on TC++3.0 */
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|             }
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| 
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|             png_ptr->offset_table_number = num_blocks;
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|             png_ptr->offset_table_count = 0;
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|             png_ptr->offset_table_count_free = 0;
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|          }
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|       }
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| 
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|       if (png_ptr->offset_table_count >= png_ptr->offset_table_number)
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|       {
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| #ifndef PNG_USER_MEM_SUPPORTED
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|          if ((png_ptr->flags&PNG_FLAG_MALLOC_NULL_MEM_OK) == 0)
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|             png_error(png_ptr, "Out of Memory"); /* Note "o" and "M" */
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|          else
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|             png_warning(png_ptr, "Out of Memory");
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| #endif
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|          return (NULL);
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|       }
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| 
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|       ret = png_ptr->offset_table_ptr[png_ptr->offset_table_count++];
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|    }
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|    else
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|       ret = farmalloc(size);
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| 
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| #ifndef PNG_USER_MEM_SUPPORTED
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|    if (ret == NULL)
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|    {
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|       if ((png_ptr->flags&PNG_FLAG_MALLOC_NULL_MEM_OK) == 0)
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|          png_error(png_ptr, "Out of memory"); /* Note "o" and "m" */
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|       else
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|          png_warning(png_ptr, "Out of memory"); /* Note "o" and "m" */
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|    }
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| #endif
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| 
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|    return (ret);
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| }
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| 
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| /* Free a pointer allocated by png_malloc().  In the default
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|  * configuration, png_ptr is not used, but is passed in case it
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|  * is needed.  If ptr is NULL, return without taking any action.
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|  */
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| void PNGAPI
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| png_free(png_structp png_ptr, png_voidp ptr)
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| {
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|    if (png_ptr == NULL || ptr == NULL)
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|       return;
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| 
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| #ifdef PNG_USER_MEM_SUPPORTED
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|    if (png_ptr->free_fn != NULL)
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|    {
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|       (*(png_ptr->free_fn))(png_ptr, ptr);
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|       return;
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|    }
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|    else
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|       png_free_default(png_ptr, ptr);
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| }
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| 
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| void PNGAPI
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| png_free_default(png_structp png_ptr, png_voidp ptr)
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| {
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| #endif /* PNG_USER_MEM_SUPPORTED */
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| 
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|    if (png_ptr == NULL || ptr == NULL)
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|       return;
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| 
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|    if (png_ptr->offset_table != NULL)
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|    {
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|       int i;
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| 
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|       for (i = 0; i < png_ptr->offset_table_count; i++)
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|       {
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|          if (ptr == png_ptr->offset_table_ptr[i])
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|          {
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|             ptr = NULL;
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|             png_ptr->offset_table_count_free++;
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|             break;
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|          }
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|       }
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|       if (png_ptr->offset_table_count_free == png_ptr->offset_table_count)
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|       {
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|          farfree(png_ptr->offset_table);
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|          farfree(png_ptr->offset_table_ptr);
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|          png_ptr->offset_table = NULL;
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|          png_ptr->offset_table_ptr = NULL;
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|       }
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|    }
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| 
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|    if (ptr != NULL)
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|    {
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|       farfree(ptr);
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|    }
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| }
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| 
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| #else /* Not the Borland DOS special memory handler */
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| 
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| /* Allocate memory for a png_struct or a png_info.  The malloc and
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|    memset can be replaced by a single call to calloc() if this is thought
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|    to improve performance noticably. */
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| png_voidp /* PRIVATE */
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| png_create_struct(int type)
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| {
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| #ifdef PNG_USER_MEM_SUPPORTED
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|    return (png_create_struct_2(type, NULL, NULL));
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| }
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| 
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| /* Allocate memory for a png_struct or a png_info.  The malloc and
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|    memset can be replaced by a single call to calloc() if this is thought
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|    to improve performance noticably. */
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| png_voidp /* PRIVATE */
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| png_create_struct_2(int type, png_malloc_ptr malloc_fn, png_voidp mem_ptr)
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| {
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| #endif /* PNG_USER_MEM_SUPPORTED */
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|    png_size_t size;
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|    png_voidp struct_ptr;
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| 
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|    if (type == PNG_STRUCT_INFO)
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|       size = png_sizeof(png_info);
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|    else if (type == PNG_STRUCT_PNG)
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|       size = png_sizeof(png_struct);
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|    else
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|       return (NULL);
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| 
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| #ifdef PNG_USER_MEM_SUPPORTED
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|    if (malloc_fn != NULL)
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|    {
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|       png_struct dummy_struct;
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|       png_structp png_ptr = &dummy_struct;
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|       png_ptr->mem_ptr=mem_ptr;
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|       struct_ptr = (*(malloc_fn))(png_ptr, size);
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|       if (struct_ptr != NULL)
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|          png_memset(struct_ptr, 0, size);
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|       return (struct_ptr);
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|    }
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| #endif /* PNG_USER_MEM_SUPPORTED */
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| 
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| #if defined(__TURBOC__) && !defined(__FLAT__)
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|    struct_ptr = (png_voidp)farmalloc(size);
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| #else
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| # if defined(_MSC_VER) && defined(MAXSEG_64K)
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|    struct_ptr = (png_voidp)halloc(size, 1);
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| # else
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|    struct_ptr = (png_voidp)malloc(size);
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| # endif
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| #endif
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|    if (struct_ptr != NULL)
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|       png_memset(struct_ptr, 0, size);
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| 
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|    return (struct_ptr);
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| }
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| 
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| 
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| /* Free memory allocated by a png_create_struct() call */
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| void /* PRIVATE */
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| png_destroy_struct(png_voidp struct_ptr)
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| {
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| #ifdef PNG_USER_MEM_SUPPORTED
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|    png_destroy_struct_2(struct_ptr, NULL, NULL);
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| }
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| 
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| /* Free memory allocated by a png_create_struct() call */
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| void /* PRIVATE */
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| png_destroy_struct_2(png_voidp struct_ptr, png_free_ptr free_fn,
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|     png_voidp mem_ptr)
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| {
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| #endif /* PNG_USER_MEM_SUPPORTED */
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|    if (struct_ptr != NULL)
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|    {
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| #ifdef PNG_USER_MEM_SUPPORTED
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|       if (free_fn != NULL)
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|       {
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|          png_struct dummy_struct;
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|          png_structp png_ptr = &dummy_struct;
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|          png_ptr->mem_ptr=mem_ptr;
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|          (*(free_fn))(png_ptr, struct_ptr);
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|          return;
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|       }
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| #endif /* PNG_USER_MEM_SUPPORTED */
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| #if defined(__TURBOC__) && !defined(__FLAT__)
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|       farfree(struct_ptr);
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| #else
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| # if defined(_MSC_VER) && defined(MAXSEG_64K)
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|       hfree(struct_ptr);
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| # else
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|       free(struct_ptr);
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| # endif
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| #endif
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|    }
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| }
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| 
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| /* Allocate memory.  For reasonable files, size should never exceed
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|  * 64K.  However, zlib may allocate more then 64K if you don't tell
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|  * it not to.  See zconf.h and png.h for more information.  zlib does
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|  * need to allocate exactly 64K, so whatever you call here must
 | |
|  * have the ability to do that.
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|  */
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| 
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| png_voidp PNGAPI
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| png_calloc(png_structp png_ptr, png_alloc_size_t size)
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| {
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|    png_voidp ret;
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| 
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|    ret = (png_malloc(png_ptr, size));
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|    if (ret != NULL)
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|       png_memset(ret,0,(png_size_t)size);
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|    return (ret);
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| }
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| 
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| png_voidp PNGAPI
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| png_malloc(png_structp png_ptr, png_alloc_size_t size)
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| {
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|    png_voidp ret;
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| 
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| #ifdef PNG_USER_MEM_SUPPORTED
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|    if (png_ptr == NULL || size == 0)
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|       return (NULL);
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| 
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|    if (png_ptr->malloc_fn != NULL)
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|       ret = ((png_voidp)(*(png_ptr->malloc_fn))(png_ptr, (png_size_t)size));
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|    else
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|       ret = (png_malloc_default(png_ptr, size));
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|    if (ret == NULL && (png_ptr->flags&PNG_FLAG_MALLOC_NULL_MEM_OK) == 0)
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|        png_error(png_ptr, "Out of Memory");
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|    return (ret);
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| }
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| 
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| png_voidp PNGAPI
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| png_malloc_default(png_structp png_ptr, png_alloc_size_t size)
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| {
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|    png_voidp ret;
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| #endif /* PNG_USER_MEM_SUPPORTED */
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| 
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|    if (png_ptr == NULL || size == 0)
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|       return (NULL);
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| 
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| #ifdef PNG_MAX_MALLOC_64K
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|    if (size > (png_uint_32)65536L)
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|    {
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| #ifndef PNG_USER_MEM_SUPPORTED
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|       if ((png_ptr->flags&PNG_FLAG_MALLOC_NULL_MEM_OK) == 0)
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|          png_error(png_ptr, "Cannot Allocate > 64K");
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|       else
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| #endif
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|          return NULL;
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|    }
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| #endif
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| 
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|    /* Check for overflow */
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| #if defined(__TURBOC__) && !defined(__FLAT__)
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|    if (size != (unsigned long)size)
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|       ret = NULL;
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|    else
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|       ret = farmalloc(size);
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| #else
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| # if defined(_MSC_VER) && defined(MAXSEG_64K)
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|    if (size != (unsigned long)size)
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|       ret = NULL;
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|    else
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|       ret = halloc(size, 1);
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| # else
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|    if (size != (size_t)size)
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|       ret = NULL;
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|    else
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|       ret = malloc((size_t)size);
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| # endif
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| #endif
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| 
 | |
| #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_voidp PNGAPI
 | |
| png_malloc_warn(png_structp png_ptr, png_alloc_size_t size)
 | |
| {
 | |
|    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 */
 | 
