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 :
29 : /*
30 : * Memory allocation and freeing are controlled by the regular library
31 : * routines malloc() and free().
32 : */
33 :
34 : GLOBAL(void *)
35 24 : jpeg_get_small (j_common_ptr cinfo, size_t sizeofobject)
36 : {
37 24 : return (void *) malloc(sizeofobject);
38 : }
39 :
40 : GLOBAL(void)
41 24 : jpeg_free_small (j_common_ptr cinfo, void * object, size_t sizeofobject)
42 : {
43 24 : free(object);
44 24 : }
45 :
46 :
47 : /*
48 : * "Large" objects are treated the same as "small" ones.
49 : * NB: although we include FAR keywords in the routine declarations,
50 : * this file won't actually work in 80x86 small/medium model; at least,
51 : * you probably won't be able to process useful-size images in only 64KB.
52 : */
53 :
54 : GLOBAL(void FAR *)
55 61 : jpeg_get_large (j_common_ptr cinfo, size_t sizeofobject)
56 : {
57 61 : return (void FAR *) malloc(sizeofobject);
58 : }
59 :
60 : GLOBAL(void)
61 61 : jpeg_free_large (j_common_ptr cinfo, void FAR * object, size_t sizeofobject)
62 : {
63 61 : free(object);
64 61 : }
65 :
66 :
67 : /*
68 : * This routine computes the total memory space available for allocation.
69 : * Here we always say, "we got all you want bud!"
70 : */
71 :
72 : GLOBAL(size_t)
73 0 : jpeg_mem_available (j_common_ptr cinfo, size_t min_bytes_needed,
74 : size_t max_bytes_needed, size_t already_allocated)
75 : {
76 0 : return max_bytes_needed;
77 : }
78 :
79 :
80 : /*
81 : * Backing store (temporary file) management.
82 : * Since jpeg_mem_available always promised the moon,
83 : * this should never be called and we can just error out.
84 : */
85 :
86 : GLOBAL(void)
87 0 : jpeg_open_backing_store (j_common_ptr cinfo, backing_store_ptr info,
88 : long total_bytes_needed)
89 : {
90 0 : ERREXIT(cinfo, JERR_NO_BACKING_STORE);
91 0 : }
92 :
93 :
94 : /*
95 : * These routines take care of any system-dependent initialization and
96 : * cleanup required. Here, there isn't any.
97 : */
98 :
99 : GLOBAL(long)
100 8 : jpeg_mem_init (j_common_ptr cinfo)
101 : {
102 8 : return 0; /* just set max_memory_to_use to 0 */
103 : }
104 :
105 : GLOBAL(void)
106 8 : jpeg_mem_term (j_common_ptr cinfo)
107 : {
108 : /* no work */
109 8 : }
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