31aee0d0c0
Fixed point APIs are now supported throughout (no missing APIs).
Internal fixed point arithmetic support exists for all internal floating
point operations.
sCAL validates the floating point strings it is passed.
Safe, albeit rudimentary, Watcom support is provided by PNG_API_RULE==2
Two new APIs exist to get the number of passes without turning on the
PNG_INTERLACE transform and to get the number of rows in the current
pass.
A new test program, pngvalid.c, validates the gamma code.
Errors in the 16 bit gamma correction (overflows) have been corrected.
cHRM chunk testing is done consistently (previously the floating point
API bypassed it, because the test really didn't work on FP, now the test
is performed on the actual values to be stored in the PNG file so it
works in the FP case too.)
Most floating point APIs now simply call the fixed point APIs after
converting the values to the fixed point form used in the PNG file.
The standard headers no longer include zlib.h, which is currently only
required for pngstruct.h and can therefore be internal.
(Patches by John Bowler)
657 lines
17 KiB
C
657 lines
17 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 1.5.0 [July 29, 2010]
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* Copyright (c) 1998-2010 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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#include "pngpriv.h"
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#if defined(PNG_READ_SUPPORTED) || defined(PNG_WRITE_SUPPORTED)
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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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/* 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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/* 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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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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# 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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/* 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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/* 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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/* 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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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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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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if (png_ptr == NULL || size == 0)
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return (NULL);
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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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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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if (png_ptr == NULL || size == 0)
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return (NULL);
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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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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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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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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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total_size = ((png_uint_32)65536L) * (png_uint_32)num_blocks+16;
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table = farmalloc(total_size);
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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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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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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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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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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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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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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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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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# 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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return (ret);
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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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# 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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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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if (png_ptr == NULL || ptr == NULL)
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return;
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if (png_ptr->offset_table != NULL)
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{
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int i;
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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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if (ptr != NULL)
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farfree(ptr);
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}
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#else /* Not the Borland DOS special memory handler */
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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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/* 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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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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# 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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# 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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return (struct_ptr);
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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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/* 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
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* have the ability to do that.
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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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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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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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# 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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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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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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if (png_ptr == NULL || size == 0)
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return (NULL);
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# 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_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_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 */
|