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 *)
jpeg_get_small(j_common_ptr cinfo,size_t sizeofobject)35 jpeg_get_small (j_common_ptr cinfo, size_t sizeofobject)
36 {
37 return (void *) malloc(sizeofobject);
38 }
39
40 GLOBAL(void)
jpeg_free_small(j_common_ptr cinfo,void * object,size_t sizeofobject)41 jpeg_free_small (j_common_ptr cinfo, void * object, size_t sizeofobject)
42 {
43 free(object);
44 }
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 *)
jpeg_get_large(j_common_ptr cinfo,size_t sizeofobject)55 jpeg_get_large (j_common_ptr cinfo, size_t sizeofobject)
56 {
57 return (void FAR *) malloc(sizeofobject);
58 }
59
60 GLOBAL(void)
jpeg_free_large(j_common_ptr cinfo,void FAR * object,size_t sizeofobject)61 jpeg_free_large (j_common_ptr cinfo, void FAR * object, size_t sizeofobject)
62 {
63 free(object);
64 }
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(long)
jpeg_mem_available(j_common_ptr cinfo,long min_bytes_needed,long max_bytes_needed,long already_allocated)73 jpeg_mem_available (j_common_ptr cinfo, long min_bytes_needed,
74 long max_bytes_needed, long already_allocated)
75 {
76 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)
jpeg_open_backing_store(j_common_ptr cinfo,backing_store_ptr info,long total_bytes_needed)87 jpeg_open_backing_store (j_common_ptr cinfo, backing_store_ptr info,
88 long total_bytes_needed)
89 {
90 ERREXIT(cinfo, JERR_NO_BACKING_STORE);
91 }
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)
jpeg_mem_init(j_common_ptr cinfo)100 jpeg_mem_init (j_common_ptr cinfo)
101 {
102 return 0; /* just set max_memory_to_use to 0 */
103 }
104
105 GLOBAL(void)
jpeg_mem_term(j_common_ptr cinfo)106 jpeg_mem_term (j_common_ptr cinfo)
107 {
108 /* no work */
109 }
110