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-rw-r--r--libpng/pngmem.c517
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diff --git a/libpng/pngmem.c b/libpng/pngmem.c
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+
+/* 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 */