www.pudn.com > imgport.rar > jmemnobs.c, change:2008-11-05,size:2881b


/* 
 * jmemnobs.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 really simple implementation of the system- 
 * dependent portion of the JPEG memory manager.  This implementation 
 * assumes that no backing-store files are needed: all required space 
 * can be obtained from malloc(). 
 * This is very portable in the sense that it'll compile on almost anything, 
 * but you'd better have lots of main memory (or virtual memory) if you want 
 * to process big images. 
 * Note that the max_memory_to_use option is ignored by this implementation. 
 */ 
 
#define JPEG_INTERNALS 
#include "jinclude.h" 
#include "jpeglib.h" 
#include "jmemsys.h"		/* import the system-dependent declarations */ 
 
#ifndef HAVE_STDLIB_H		/* <stdlib.h> should declare malloc(),free() */ 
extern void * malloc JPP((size_t size)); 
extern void free JPP((void *ptr)); 
#endif 
 
 
/* 
 * 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); 
} 
 
 
/* 
 * This routine computes the total memory space available for allocation. 
 * Here we always say, "we got all you want bud!" 
 */ 
 
GLOBAL(long) 
jpeg_mem_available (j_common_ptr cinfo, long min_bytes_needed, 
		    long max_bytes_needed, long already_allocated) 
{ 
  return max_bytes_needed; 
} 
 
 
/* 
 * Backing store (temporary file) management. 
 * Since jpeg_mem_available always promised the moon, 
 * this should never be called and we can just error out. 
 */ 
 
GLOBAL(void) 
jpeg_open_backing_store (j_common_ptr cinfo, backing_store_ptr info, 
			 long total_bytes_needed) 
{ 
  ERREXIT(cinfo, JERR_NO_BACKING_STORE); 
} 
 
 
/* 
 * These routines take care of any system-dependent initialization and 
 * cleanup required.  Here, there isn't any. 
 */ 
 
GLOBAL(long) 
jpeg_mem_init (j_common_ptr cinfo) 
{ 
  return 0;			/* just set max_memory_to_use to 0 */ 
} 
 
GLOBAL(void) 
jpeg_mem_term (j_common_ptr cinfo) 
{ 
  /* no work */ 
}