📄 jmemansi.c
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/*
* jmemansi.c
*
* Copyright (C) 1992-1996, Thomas G. Lane.
* This file is part of the Independent JPEG Group's software.
* For conditions of distribution and use, see the accompanying README file.
*
* This file provides a simple generic implementation of the system-
* dependent portion of the JPEG memory manager. This implementation
* assumes that you have the ANSI-standard library routine tmpfile().
* Also, the problem of determining the amount of memory available
* is shoved onto the user.
*/
#define JPEG_INTERNALS
#include "jinclude.h"
#include "jpeglib.h"
#include "jmemsys.h" /* import the system-dependent declarations */
#include "includes.h"
#ifndef SEEK_SET /* pre-ANSI systems may not define this; */
#define SEEK_SET 0 /* if not, assume 0 is correct */
#endif
#if 0 //use the memory management of uCOSii
/* number of bytes per allocation */
#define HEAPBLKSIZE 0x8000
/* number of allocations available */
#define HEAPBLKS 13
/* our heap */
OS_MEM *heap;
unsigned char heapmem[HEAPBLKS * HEAPBLKSIZE];
void *malloc ( size_t size )
{
INT8U err = OS_NO_ERR;
void *alloc = 0;
static int n=1;
// printf("%d malloc size=%ld\n",n++,size);
/* initialize, if necessary */
// OS_ENTER_CRITICAL();
if( !heap )
heap = OSMemCreate( heapmem, HEAPBLKS,
HEAPBLKSIZE, &err );
// OS_EXIT_CRITICAL();
if( heap && err == OS_NO_ERR ) {
/* if the request fits the heap block length,
then make the allocation from the heap */
if( size <= HEAPBLKSIZE )
alloc = OSMemGet( heap, &err );
/* otherwise, we're sunk */
else err = OS_MEM_NO_FREE_BLKS;
}
/* deny the allocation on errors */
if( err != OS_NO_ERR )
alloc = 0;
return alloc;
}
/*
* Memory allocation and freeing are controlled by the regular library
* routines malloc() and free().
*/
GLOBAL(void *)
jpeg_get_small (j_common_ptr cinfo, size_t sizeofobject)
{
return (void *) malloc(sizeofobject);
}
GLOBAL(void)
jpeg_free_small (j_common_ptr cinfo, void * object, size_t sizeofobject)
{
// free(object);
}
/*
* "Large" objects are treated the same as "small" ones.
* NB: although we include FAR keywords in the routine declarations,
* this file won't actually work in 80x86 small/medium model; at least,
* you probably won't be able to process useful-size images in only 64KB.
*/
GLOBAL(void FAR *)
jpeg_get_large (j_common_ptr cinfo, size_t sizeofobject)
{
return (void FAR *) malloc(sizeofobject);
}
GLOBAL(void)
jpeg_free_large (j_common_ptr cinfo, void FAR * object, size_t sizeofobject)
{
// free(object);
}
#else
/* number of bytes per allocation */
#define HEAPSIZE 0x15000
/* our heap */
static unsigned char heapmem[HEAPSIZE];
static void *alloc = heapmem;
void *malloc ( size_t size )
{
alloc += size;
#if 0
{
static int n=1, t=0;
t +=size;
printf("%d malloc size=%ld total=0x%lx\n",n++,size,t);
printf("alloc = %p\n", alloc - size);
}
#endif
if ((unsigned int)alloc > (unsigned int)&heapmem[HEAPSIZE])
return 0;
return (void *) (alloc - size);
}
void free ( size_t size )
{
alloc -= size;
}
/*
* Memory allocation and freeing are controlled by the regular library
* routines malloc() and free().
*/
GLOBAL(void *)
jpeg_get_small (j_common_ptr cinfo, size_t sizeofobject)
{
return (void *) malloc(sizeofobject);
}
GLOBAL(void)
jpeg_free_small (j_common_ptr cinfo, void * object, size_t sizeofobject)
{
free(sizeofobject);
}
/*
* "Large" objects are treated the same as "small" ones.
* NB: although we include FAR keywords in the routine declarations,
* this file won't actually work in 80x86 small/medium model; at least,
* you probably won't be able to process useful-size images in only 64KB.
*/
GLOBAL(void *)
jpeg_get_large (j_common_ptr cinfo, size_t sizeofobject)
{
return malloc(sizeofobject);
}
GLOBAL(void)
jpeg_free_large (j_common_ptr cinfo, void * object, size_t sizeofobject)
{
free(sizeofobject);
}
#endif
/*
* This routine computes the total memory space available for allocation.
* It's impossible to do this in a portable way; our current solution is
* to make the user tell us (with a default value set at compile time).
* If you can actually get the available space, it's a good idea to subtract
* a slop factor of 5% or so.
*/
#ifndef DEFAULT_MAX_MEM /* so can override from makefile */
#define DEFAULT_MAX_MEM 1000000L /* default: one megabyte */
#endif
GLOBAL(long)
jpeg_mem_available (j_common_ptr cinfo, long min_bytes_needed,
long max_bytes_needed, long already_allocated)
{
return cinfo->mem->max_memory_to_use - already_allocated;
}
/*
* Backing store (temporary file) management.
* Backing store objects are only used when the value returned by
* jpeg_mem_available is less than the total space needed. You can dispense
* with these routines if you have plenty of virtual memory; see jmemnobs.c.
*/
METHODDEF(void)
read_backing_store (j_common_ptr cinfo, backing_store_ptr info,
void FAR * buffer_address,
long file_offset, long byte_count)
{
if (FS_FSeek(info->temp_file, file_offset, FS_SEEK_SET))
ERREXIT(cinfo, JERR_TFILE_SEEK);
if (JFREAD(info->temp_file, buffer_address, byte_count)
!= (size_t) byte_count)
ERREXIT(cinfo, JERR_TFILE_READ);
}
METHODDEF(void)
write_backing_store (j_common_ptr cinfo, backing_store_ptr info,
void FAR * buffer_address,
long file_offset, long byte_count)
{
if (FS_FSeek(info->temp_file, file_offset, FS_SEEK_SET))
ERREXIT(cinfo, JERR_TFILE_SEEK);
if (JFWRITE(info->temp_file, buffer_address, byte_count)
!= (size_t) byte_count)
ERREXIT(cinfo, JERR_TFILE_WRITE);
}
METHODDEF(void)
close_backing_store (j_common_ptr cinfo, backing_store_ptr info)
{
FS_FClose(info->temp_file);
FS_Remove(info->temp_name); /* delete the file */
}
/*
* Initial opening of a backing-store object.
*
* This version uses tmpfile(), which constructs a suitable file name
* behind the scenes. We don't have to use info->temp_name[] at all;
* indeed, we can't even find out the actual name of the temp file.
*/
GLOBAL(void)
jpeg_open_backing_store (j_common_ptr cinfo, backing_store_ptr info,
long total_bytes_needed)
{
strcpy(info->temp_name,"jpegtmp");
if((info->temp_file = FS_FOpen(info->temp_name, "w+b")) == NULL)
{
printf("File %s not found! \n",info->temp_name);
ERREXITS(cinfo, JERR_TFILE_CREATE, info->temp_name);
}
info->read_backing_store = read_backing_store;
info->write_backing_store = write_backing_store;
info->close_backing_store = close_backing_store;
}
/*
* These routines take care of any system-dependent initialization and
* cleanup required.
*/
GLOBAL(long)
jpeg_mem_init (j_common_ptr cinfo)
{
return DEFAULT_MAX_MEM; /* default for max_memory_to_use */
}
GLOBAL(void)
jpeg_mem_term (j_common_ptr cinfo)
{
/* no work */
}
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