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jinclude.h
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1/*
2 * jinclude.h
3 *
4 * Copyright (C) 1991-1994, 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 exists to provide a single place to fix any problems with
9 * including the wrong system include files. (Common problems are taken
10 * care of by the standard jconfig symbols, but on really weird systems
11 * you may have to edit this file.)
12 *
13 * NOTE: this file is NOT intended to be included by applications using the
14 * JPEG library. Most applications need only include jpeglib.h.
15 */
16
17
18/* Include auto-config file to find out which system include files we need. */
19
20#include "jconfig.h" /* auto configuration options */
21#define JCONFIG_INCLUDED /* so that jpeglib.h doesn't do it again */
22
23/*
24 * We need the NULL macro and size_t typedef.
25 * On an ANSI-conforming system it is sufficient to include <stddef.h>.
26 * Otherwise, we get them from <stdlib.h> or <stdio.h>; we may have to
27 * pull in <sys/types.h> as well.
28 * Note that the core JPEG library does not require <stdio.h>;
29 * only the default error handler and data source/destination modules do.
30 * But we must pull it in because of the references to FILE in jpeglib.h.
31 * You can remove those references if you want to compile without <stdio.h>.
32 */
33
34#ifdef HAVE_STDDEF_H
35#include <stddef.h>
36#endif
37
38#ifdef HAVE_STDLIB_H
39#include <stdlib.h>
40#endif
41
42#ifdef NEED_SYS_TYPES_H
43#include <sys/types.h>
44#endif
45
46#include <stdio.h>
47
48/*
49 * We need memory copying and zeroing functions, plus strncpy().
50 * ANSI and System V implementations declare these in <string.h>.
51 * BSD doesn't have the mem() functions, but it does have bcopy()/bzero().
52 * Some systems may declare memset and memcpy in <memory.h>.
53 *
54 * NOTE: we assume the size parameters to these functions are of type size_t.
55 * Change the casts in these macros if not!
56 */
57
58#ifdef NEED_BSD_STRINGS
59
60#include <strings.h>
61#define MEMZERO(target,size) bzero((void *)(target), (size_t)(size))
62#define MEMCOPY(dest,src,size) bcopy((const void *)(src), (void *)(dest), (size_t)(size))
63
64#else /* not BSD, assume ANSI/SysV string lib */
65
66#include <string.h>
67#define MEMZERO(target,size) memset((void *)(target), 0, (size_t)(size))
68#define MEMCOPY(dest,src,size) memcpy((void *)(dest), (const void *)(src), (size_t)(size))
69
70#endif
71
72/*
73 * In ANSI C, and indeed any rational implementation, size_t is also the
74 * type returned by sizeof(). However, it seems there are some irrational
75 * implementations out there, in which sizeof() returns an int even though
76 * size_t is defined as long or unsigned long. To ensure consistent results
77 * we always use this SIZEOF() macro in place of using sizeof() directly.
78 */
79
80#define SIZEOF(object) ((size_t) sizeof(object))
81
82/*
83 * The modules that use fread() and fwrite() always invoke them through
84 * these macros. On some systems you may need to twiddle the argument casts.
85 * CAUTION: argument order is different from underlying functions!
86 */
87
88#define JFREAD(file,buf,sizeofbuf) \
89 ((size_t) fread((void *) (buf), (size_t) 1, (size_t) (sizeofbuf), (file)))
90#define JFWRITE(file,buf,sizeofbuf) \
91 ((size_t) fwrite((const void *) (buf), (size_t) 1, (size_t) (sizeofbuf), (file)))
jconfig.h