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      1 /*
      2  * jmemnobs.c
      3  *
      4  * Copyright (C) 1992-1996, Thomas G. Lane.
      5  * This file is part of the Independent JPEG Group's software.
      6  * For conditions of distribution and use, see the accompanying README file.
      7  *
      8  * This file provides a really simple implementation of the system-
      9  * dependent portion of the JPEG memory manager.  This implementation
     10  * assumes that no backing-store files are needed: all required space
     11  * can be obtained from malloc().
     12  * This is very portable in the sense that it'll compile on almost anything,
     13  * but you'd better have lots of main memory (or virtual memory) if you want
     14  * to process big images.
     15  * Note that the max_memory_to_use option is ignored by this implementation.
     16  */
     17 
     18 #define JPEG_INTERNALS
     19 #include "jinclude.h"
     20 #include "jpeglib.h"
     21 #include "jmemsys.h"		/* import the system-dependent declarations */
     22 
     23 #ifndef HAVE_STDLIB_H		/* <stdlib.h> should declare malloc(),free() */
     24 extern void * malloc JPP((size_t size));
     25 extern void free JPP((void *ptr));
     26 #endif
     27 
     28 #if defined(_FX_MANAGED_CODE_) && defined(__cplusplus)
     29 extern "C" {
     30 #endif
     31 
     32 void*	FXMEM_DefaultAlloc(int byte_size, int);
     33 void	FXMEM_DefaultFree(void* pointer, int);
     34 
     35 #if defined(_FX_MANAGED_CODE_) && defined(__cplusplus)
     36 }
     37 #endif
     38 
     39 /*
     40  * Memory allocation and freeing are controlled by the regular library
     41  * routines malloc() and free().
     42  */
     43 
     44 GLOBAL(void *)
     45 jpeg_get_small (j_common_ptr cinfo, size_t sizeofobject)
     46 {
     47 //  return (void *) malloc(sizeofobject);
     48 	return FXMEM_DefaultAlloc(sizeofobject, 0);
     49 }
     50 
     51 GLOBAL(void)
     52 jpeg_free_small (j_common_ptr cinfo, void * object, size_t sizeofobject)
     53 {
     54 //  free(object);
     55 	FXMEM_DefaultFree(object, 0);
     56 }
     57 
     58 
     59 /*
     60  * "Large" objects are treated the same as "small" ones.
     61  * NB: although we include FAR keywords in the routine declarations,
     62  * this file won't actually work in 80x86 small/medium model; at least,
     63  * you probably won't be able to process useful-size images in only 64KB.
     64  */
     65 
     66 GLOBAL(void FAR *)
     67 jpeg_get_large (j_common_ptr cinfo, size_t sizeofobject)
     68 {
     69 //  return (void FAR *) malloc(sizeofobject);
     70 	return FXMEM_DefaultAlloc(sizeofobject, 0);
     71 }
     72 
     73 GLOBAL(void)
     74 jpeg_free_large (j_common_ptr cinfo, void FAR * object, size_t sizeofobject)
     75 {
     76 //  free(object);
     77 	FXMEM_DefaultFree(object, 0);
     78 }
     79 
     80 
     81 /*
     82  * This routine computes the total memory space available for allocation.
     83  * Here we always say, "we got all you want bud!"
     84  */
     85 
     86 GLOBAL(long)
     87 jpeg_mem_available (j_common_ptr cinfo, long min_bytes_needed,
     88 		    long max_bytes_needed, long already_allocated)
     89 {
     90   return max_bytes_needed;
     91 }
     92 
     93 
     94 /*
     95  * Backing store (temporary file) management.
     96  * Since jpeg_mem_available always promised the moon,
     97  * this should never be called and we can just error out.
     98  */
     99 
    100 GLOBAL(void)
    101 jpeg_open_backing_store (j_common_ptr cinfo, backing_store_ptr info,
    102 			 long total_bytes_needed)
    103 {
    104   ERREXIT(cinfo, JERR_NO_BACKING_STORE);
    105 }
    106 
    107 
    108 /*
    109  * These routines take care of any system-dependent initialization and
    110  * cleanup required.  Here, there isn't any.
    111  */
    112 
    113 GLOBAL(long)
    114 jpeg_mem_init (j_common_ptr cinfo)
    115 {
    116   return 0;			/* just set max_memory_to_use to 0 */
    117 }
    118 
    119 GLOBAL(void)
    120 jpeg_mem_term (j_common_ptr cinfo)
    121 {
    122   /* no work */
    123 }
    124