liblzma: Improve documentation in index.h
[xz/debian.git] / src / common / sysdefs.h
blob97be4ee380d04ec84735f83cf3b00c8b4f3578ec
1 ///////////////////////////////////////////////////////////////////////////////
2 //
3 /// \file sysdefs.h
4 /// \brief Common includes, definitions, system-specific things etc.
5 ///
6 /// This file is used also by the lzma command line tool, that's why this
7 /// file is separate from common.h.
8 //
9 // Author: Lasse Collin
11 // This file has been put into the public domain.
12 // You can do whatever you want with this file.
14 ///////////////////////////////////////////////////////////////////////////////
16 #ifndef LZMA_SYSDEFS_H
17 #define LZMA_SYSDEFS_H
19 //////////////
20 // Includes //
21 //////////////
23 #ifdef HAVE_CONFIG_H
24 # include <config.h>
25 #endif
27 // Get standard-compliant stdio functions under MinGW and MinGW-w64.
28 #ifdef __MINGW32__
29 # define __USE_MINGW_ANSI_STDIO 1
30 #endif
32 // size_t and NULL
33 #include <stddef.h>
35 #ifdef HAVE_INTTYPES_H
36 # include <inttypes.h>
37 #endif
39 // C99 says that inttypes.h always includes stdint.h, but some systems
40 // don't do that, and require including stdint.h separately.
41 #ifdef HAVE_STDINT_H
42 # include <stdint.h>
43 #endif
45 // Some pre-C99 systems have SIZE_MAX in limits.h instead of stdint.h. The
46 // limits are also used to figure out some macros missing from pre-C99 systems.
47 #include <limits.h>
49 // Be more compatible with systems that have non-conforming inttypes.h.
50 // We assume that int is 32-bit and that long is either 32-bit or 64-bit.
51 // Full Autoconf test could be more correct, but this should work well enough.
52 // Note that this duplicates some code from lzma.h, but this is better since
53 // we can work without inttypes.h thanks to Autoconf tests.
54 #ifndef UINT32_C
55 # if UINT_MAX != 4294967295U
56 # error UINT32_C is not defined and unsigned int is not 32-bit.
57 # endif
58 # define UINT32_C(n) n ## U
59 #endif
60 #ifndef UINT32_MAX
61 # define UINT32_MAX UINT32_C(4294967295)
62 #endif
63 #ifndef PRIu32
64 # define PRIu32 "u"
65 #endif
66 #ifndef PRIx32
67 # define PRIx32 "x"
68 #endif
69 #ifndef PRIX32
70 # define PRIX32 "X"
71 #endif
73 #if ULONG_MAX == 4294967295UL
74 # ifndef UINT64_C
75 # define UINT64_C(n) n ## ULL
76 # endif
77 # ifndef PRIu64
78 # define PRIu64 "llu"
79 # endif
80 # ifndef PRIx64
81 # define PRIx64 "llx"
82 # endif
83 # ifndef PRIX64
84 # define PRIX64 "llX"
85 # endif
86 #else
87 # ifndef UINT64_C
88 # define UINT64_C(n) n ## UL
89 # endif
90 # ifndef PRIu64
91 # define PRIu64 "lu"
92 # endif
93 # ifndef PRIx64
94 # define PRIx64 "lx"
95 # endif
96 # ifndef PRIX64
97 # define PRIX64 "lX"
98 # endif
99 #endif
100 #ifndef UINT64_MAX
101 # define UINT64_MAX UINT64_C(18446744073709551615)
102 #endif
104 // Incorrect(?) SIZE_MAX:
105 // - Interix headers typedef size_t to unsigned long,
106 // but a few lines later define SIZE_MAX to INT32_MAX.
107 // - SCO OpenServer (x86) headers typedef size_t to unsigned int
108 // but define SIZE_MAX to INT32_MAX.
109 #if defined(__INTERIX) || defined(_SCO_DS)
110 # undef SIZE_MAX
111 #endif
113 // The code currently assumes that size_t is either 32-bit or 64-bit.
114 #ifndef SIZE_MAX
115 # if SIZEOF_SIZE_T == 4
116 # define SIZE_MAX UINT32_MAX
117 # elif SIZEOF_SIZE_T == 8
118 # define SIZE_MAX UINT64_MAX
119 # else
120 # error size_t is not 32-bit or 64-bit
121 # endif
122 #endif
123 #if SIZE_MAX != UINT32_MAX && SIZE_MAX != UINT64_MAX
124 # error size_t is not 32-bit or 64-bit
125 #endif
127 #include <stdlib.h>
128 #include <assert.h>
130 // Pre-C99 systems lack stdbool.h. All the code in XZ Utils must be written
131 // so that it works with fake bool type, for example:
133 // bool foo = (flags & 0x100) != 0;
134 // bool bar = !!(flags & 0x100);
136 // This works with the real C99 bool but breaks with fake bool:
138 // bool baz = (flags & 0x100);
140 #ifdef HAVE_STDBOOL_H
141 # include <stdbool.h>
142 #else
143 # if ! HAVE__BOOL
144 typedef unsigned char _Bool;
145 # endif
146 # define bool _Bool
147 # define false 0
148 # define true 1
149 # define __bool_true_false_are_defined 1
150 #endif
152 #include <string.h>
154 // As of MSVC 2013, inline and restrict are supported with
155 // non-standard keywords.
156 #if defined(_WIN32) && defined(_MSC_VER)
157 # ifndef inline
158 # define inline __inline
159 # endif
160 # ifndef restrict
161 # define restrict __restrict
162 # endif
163 #endif
165 ////////////
166 // Macros //
167 ////////////
169 #undef memzero
170 #define memzero(s, n) memset(s, 0, n)
172 // NOTE: Avoid using MIN() and MAX(), because even conditionally defining
173 // those macros can cause some portability trouble, since on some systems
174 // the system headers insist defining their own versions.
175 #define my_min(x, y) ((x) < (y) ? (x) : (y))
176 #define my_max(x, y) ((x) > (y) ? (x) : (y))
178 #ifndef ARRAY_SIZE
179 # define ARRAY_SIZE(array) (sizeof(array) / sizeof((array)[0]))
180 #endif
182 #if defined(__GNUC__) \
183 && ((__GNUC__ == 4 && __GNUC_MINOR__ >= 3) || __GNUC__ > 4)
184 # define lzma_attr_alloc_size(x) __attribute__((__alloc_size__(x)))
185 #else
186 # define lzma_attr_alloc_size(x)
187 #endif
189 #endif