mewin/libpng
1
0
Fork 0
mirror of https://git.code.sf.net/p/libpng/code.git synced 2025-07-10 18:04:09 +02:00
Code Issues Projects Releases Wiki Activity

Imported from libpng-0.89.tar

Browse Source
This commit is contained in:
Guy Schalnat
1996-06-05 15:50:50 -05:00
committed by Glenn Randers-Pehrson
parent b2e01bd505
commit e5a37797b4
38 changed files with 3198 additions and 2062 deletions
Download Patch File Download Diff File Expand all files Collapse all files

136
pngmem.c
View File

@@ -1,10 +1,10 @@
/* pngmem.c - stub functions for memory allocation
libpng 1.0 beta 2 - version 0.88
libpng 1.0 beta 3 - version 0.89
For conditions of distribution and use, see copyright notice in png.h
Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.
January 25, 1996
May 25, 1996
This file provides a location for all memory allocation. Users which
need special memory handling are expected to modify the code in this file
@@ -17,6 +17,39 @@
#if defined(__TURBOC__) && !defined(_Windows) && !defined(__FLAT__)
/* if you change this, be sure to change the one in png.h also */
/* Allocate memory for a png_struct. The malloc and memset can be replaced
* by a single call to calloc() if this is thought to improve performance.
*/
png_voidp
png_create_struct(uInt type)
{
png_size_t type;
png_voidp struct_ptr;
if (type == PNG_STRUCT_INFO)
size = sizeof(png_info);
else if (type == PNG_STRUCT_PNG)
size = sizeof(png_struct);
else
return (png_voidp)NULL;
if ((struct_ptr = (png_voidp)farmalloc(size)) != NULL)
{
png_memset(struct_ptr, 0, size);
}
return (struct_ptr);
}
/* Free memory allocated by a png_create_struct() call */
void
png_destroy_struct(png_voidp struct_ptr)
{
if (struct_ptr)
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
@@ -27,7 +60,9 @@
It gives you a segment with an offset of 8 (perhaps to store it's
memory stuff). zlib doesn't like this at all, so we have to
detect and deal with it. This code should not be needed in
Windows or OS/2 modes, and only in 16 bit mode.
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.
*/
png_voidp
@@ -35,7 +70,7 @@ png_large_malloc(png_structp png_ptr, png_uint_32 size)
{
png_voidp ret;
if (!png_ptr || !size)
return ((voidp)0);
return ((voidp)NULL);
#ifdef PNG_MAX_MALLOC_64K
if (size > (png_uint_32)65536L)
@@ -58,7 +93,7 @@ png_large_malloc(png_structp png_ptr, png_uint_32 size)
if (ret)
farfree(ret);
ret = 0;
ret = NULL;
num_blocks = (int)(1 << (png_ptr->zlib_window_bits - 14));
if (num_blocks < 1)
@@ -68,7 +103,7 @@ png_large_malloc(png_structp png_ptr, png_uint_32 size)
else
num_blocks++;
total_size = ((png_uint_32)65536L) * (png_uint_32)num_blocks;
total_size = ((png_uint_32)65536L) * (png_uint_32)num_blocks+16;
table = farmalloc(total_size);
@@ -77,27 +112,25 @@ png_large_malloc(png_structp png_ptr, png_uint_32 size)
png_error(png_ptr, "Out of Memory");
}
if ((long)table & 0xffff)
if ((long)table & 0xfff0)
{
farfree(table);
total_size += (png_uint_32)65536L;
}
table = farmalloc(total_size);
if (!table)
{
png_error(png_ptr, "Out of Memory");
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));
hptr = (png_byte huge *)table;
if ((long)hptr & 0xffff)
if (!png_ptr->offset_table_ptr)
{
hptr = (png_byte huge *)((long)(hptr) & 0xffff0000L);
hptr += 65536L;
png_error(png_ptr, "Out of memory");
}
hptr = (png_byte huge *)table;
if ((long)hptr & 0xf)
{
hptr = (png_byte huge *)((long)(hptr) & 0xfffffff0L);
hptr += 16L;
}
for (i = 0; i < num_blocks; i++)
{
@@ -109,12 +142,12 @@ png_large_malloc(png_structp png_ptr, png_uint_32 size)
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++];
}
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);
@@ -167,13 +200,63 @@ png_large_free(png_structp png_ptr, png_voidp 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
png_create_struct(uInt type)
{
size_t size;
png_voidp struct_ptr;
if (type == PNG_STRUCT_INFO)
size = sizeof(png_info);
else if (type == PNG_STRUCT_PNG)
size = sizeof(png_struct);
else
return (png_voidp)NULL;
#if defined(__TURBOC__) && !defined(__FLAT__)
if ((struct_ptr = (png_voidp)farmalloc(size)) != NULL)
#else
# if defined(_MSC_VER) && defined(MAXSEG_64K)
if ((struct_ptr = (png_voidp)halloc(size)) != NULL)
# else
if ((struct_ptr = (png_voidp)malloc(size)) != NULL)
# endif
#endif
{
png_memset(struct_ptr, 0, size);
}
return (struct_ptr);
}
/* Free memory allocated by a png_create_struct() call */
void
png_destroy_struct(png_voidp struct_ptr)
{
if (struct_ptr)
#if defined(__TURBOC__) && !defined(__FLAT__)
farfree(struct_ptr);
#else
# if defined(_MSC_VER) && defined(MAXSEG_64K)
hfree(struct_ptr);
# else
free(struct_ptr);
# endif
#endif
}
/* Allocate memory. For reasonable files, size should never exceed
64K. However, zlib may allocate more then 64K if you don't tell
it not to. See zconf.h and png.h for more information. zlib does
need to allocate exactly 64K, so whatever you call here must
have the ability to do that. */
png_voidp
png_large_malloc(png_structp png_ptr, png_uint_32 size)
{
@@ -300,4 +383,3 @@ png_free(png_structp png_ptr, void * ptr)
free(ptr);
}