Add av_printf_format, for marking printf style format strings and their parameters
[libav.git] / libavutil / attributes.h
1 /*
2 * copyright (c) 2006 Michael Niedermayer <michaelni@gmx.at>
3 *
4 * This file is part of Libav.
5 *
6 * Libav is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Lesser General Public
8 * License as published by the Free Software Foundation; either
9 * version 2.1 of the License, or (at your option) any later version.
10 *
11 * Libav is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * Lesser General Public License for more details.
15 *
16 * You should have received a copy of the GNU Lesser General Public
17 * License along with Libav; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19 */
20
21 /**
22 * @file
23 * Macro definitions for various function/variable attributes
24 */
25
26 #ifndef AVUTIL_ATTRIBUTES_H
27 #define AVUTIL_ATTRIBUTES_H
28
29 #ifdef __GNUC__
30 # define AV_GCC_VERSION_AT_LEAST(x,y) (__GNUC__ > x || __GNUC__ == x && __GNUC_MINOR__ >= y)
31 #else
32 # define AV_GCC_VERSION_AT_LEAST(x,y) 0
33 #endif
34
35 #ifndef av_always_inline
36 #if AV_GCC_VERSION_AT_LEAST(3,1)
37 # define av_always_inline __attribute__((always_inline)) inline
38 #else
39 # define av_always_inline inline
40 #endif
41 #endif
42
43 #ifndef av_noinline
44 #if AV_GCC_VERSION_AT_LEAST(3,1)
45 # define av_noinline __attribute__((noinline))
46 #else
47 # define av_noinline
48 #endif
49 #endif
50
51 #ifndef av_pure
52 #if AV_GCC_VERSION_AT_LEAST(3,1)
53 # define av_pure __attribute__((pure))
54 #else
55 # define av_pure
56 #endif
57 #endif
58
59 #ifndef av_const
60 #if AV_GCC_VERSION_AT_LEAST(2,6)
61 # define av_const __attribute__((const))
62 #else
63 # define av_const
64 #endif
65 #endif
66
67 #ifndef av_cold
68 #if AV_GCC_VERSION_AT_LEAST(4,3)
69 # define av_cold __attribute__((cold))
70 #else
71 # define av_cold
72 #endif
73 #endif
74
75 #ifndef av_flatten
76 #if AV_GCC_VERSION_AT_LEAST(4,1)
77 # define av_flatten __attribute__((flatten))
78 #else
79 # define av_flatten
80 #endif
81 #endif
82
83 #ifndef attribute_deprecated
84 #if AV_GCC_VERSION_AT_LEAST(3,1)
85 # define attribute_deprecated __attribute__((deprecated))
86 #else
87 # define attribute_deprecated
88 #endif
89 #endif
90
91 #ifndef av_unused
92 #if defined(__GNUC__)
93 # define av_unused __attribute__((unused))
94 #else
95 # define av_unused
96 #endif
97 #endif
98
99 /**
100 * Mark a variable as used and prevent the compiler from optimizing it
101 * away. This is useful for variables accessed only from inline
102 * assembler without the compiler being aware.
103 */
104 #ifndef av_used
105 #if AV_GCC_VERSION_AT_LEAST(3,1)
106 # define av_used __attribute__((used))
107 #else
108 # define av_used
109 #endif
110 #endif
111
112 #ifndef av_alias
113 #if AV_GCC_VERSION_AT_LEAST(3,3)
114 # define av_alias __attribute__((may_alias))
115 #else
116 # define av_alias
117 #endif
118 #endif
119
120 #ifndef av_uninit
121 #if defined(__GNUC__) && !defined(__ICC)
122 # define av_uninit(x) x=x
123 #else
124 # define av_uninit(x) x
125 #endif
126 #endif
127
128 #ifdef __GNUC__
129 # define av_builtin_constant_p __builtin_constant_p
130 # define av_printf_format(fmtpos, attrpos) __attribute__((__format__(__printf__, fmtpos, attrpos)))
131 #else
132 # define av_builtin_constant_p(x) 0
133 # define av_printf_format(fmtpos, attrpos)
134 #endif
135
136 #endif /* AVUTIL_ATTRIBUTES_H */