ecd535b808c2fde645e885111082409aeca91423
[libav.git] / libavutil / internal.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 * common internal API header
24 */
25
26 #ifndef AVUTIL_INTERNAL_H
27 #define AVUTIL_INTERNAL_H
28
29 #if !defined(DEBUG) && !defined(NDEBUG)
30 # define NDEBUG
31 #endif
32
33 #include <limits.h>
34 #include <stdint.h>
35 #include <stddef.h>
36 #include <assert.h>
37 #include "config.h"
38 #include "attributes.h"
39 #include "dict.h"
40
41 #if ARCH_X86
42 # include "x86/emms.h"
43 #endif
44
45 #ifndef emms_c
46 # define emms_c()
47 #endif
48
49 #ifndef attribute_align_arg
50 #if ARCH_X86_32 && AV_GCC_VERSION_AT_LEAST(4,2)
51 # define attribute_align_arg __attribute__((force_align_arg_pointer))
52 #else
53 # define attribute_align_arg
54 #endif
55 #endif
56
57 #if defined(_MSC_VER) && CONFIG_SHARED
58 # define av_export __declspec(dllimport)
59 #else
60 # define av_export
61 #endif
62
63 #if HAVE_PRAGMA_DEPRECATED
64 # if defined(__ICL)
65 # define FF_DISABLE_DEPRECATION_WARNINGS __pragma(warning(push)) __pragma(warning(disable:1478))
66 # define FF_ENABLE_DEPRECATION_WARNINGS __pragma(warning(pop))
67 # elif defined(_MSC_VER)
68 # define FF_DISABLE_DEPRECATION_WARNINGS __pragma(warning(push)) __pragma(warning(disable:4996))
69 # define FF_ENABLE_DEPRECATION_WARNINGS __pragma(warning(pop))
70 # else
71 # define FF_DISABLE_DEPRECATION_WARNINGS _Pragma("GCC diagnostic ignored \"-Wdeprecated-declarations\"")
72 # define FF_ENABLE_DEPRECATION_WARNINGS _Pragma("GCC diagnostic warning \"-Wdeprecated-declarations\"")
73 # endif
74 #else
75 # define FF_DISABLE_DEPRECATION_WARNINGS
76 # define FF_ENABLE_DEPRECATION_WARNINGS
77 #endif
78
79 #ifndef INT_BIT
80 # define INT_BIT (CHAR_BIT * sizeof(int))
81 #endif
82
83 // Some broken preprocessors need a second expansion
84 // to be forced to tokenize __VA_ARGS__
85 #define E1(x) x
86
87 #define LOCAL_ALIGNED_A(a, t, v, s, o, ...) \
88 uint8_t la_##v[sizeof(t s o) + (a)]; \
89 t (*v) o = (void *)FFALIGN((uintptr_t)la_##v, a)
90
91 #define LOCAL_ALIGNED_D(a, t, v, s, o, ...) \
92 DECLARE_ALIGNED(a, t, la_##v) s o; \
93 t (*v) o = la_##v
94
95 #define LOCAL_ALIGNED(a, t, v, ...) E1(LOCAL_ALIGNED_A(a, t, v, __VA_ARGS__,,))
96
97 #if HAVE_LOCAL_ALIGNED_8
98 # define LOCAL_ALIGNED_8(t, v, ...) E1(LOCAL_ALIGNED_D(8, t, v, __VA_ARGS__,,))
99 #else
100 # define LOCAL_ALIGNED_8(t, v, ...) LOCAL_ALIGNED(8, t, v, __VA_ARGS__)
101 #endif
102
103 #if HAVE_LOCAL_ALIGNED_16
104 # define LOCAL_ALIGNED_16(t, v, ...) E1(LOCAL_ALIGNED_D(16, t, v, __VA_ARGS__,,))
105 #else
106 # define LOCAL_ALIGNED_16(t, v, ...) LOCAL_ALIGNED(16, t, v, __VA_ARGS__)
107 #endif
108
109 #define FF_ALLOC_OR_GOTO(ctx, p, size, label)\
110 {\
111 p = av_malloc(size);\
112 if (p == NULL && (size) != 0) {\
113 av_log(ctx, AV_LOG_ERROR, "Cannot allocate memory.\n");\
114 goto label;\
115 }\
116 }
117
118 #define FF_ALLOCZ_OR_GOTO(ctx, p, size, label)\
119 {\
120 p = av_mallocz(size);\
121 if (p == NULL && (size) != 0) {\
122 av_log(ctx, AV_LOG_ERROR, "Cannot allocate memory.\n");\
123 goto label;\
124 }\
125 }
126
127 #include "libm.h"
128
129 #if defined(_MSC_VER)
130 #pragma comment(linker, "/include:"EXTERN_PREFIX"avpriv_strtod")
131 #pragma comment(linker, "/include:"EXTERN_PREFIX"avpriv_snprintf")
132 #endif
133
134 /**
135 * Return NULL if CONFIG_SMALL is true, otherwise the argument
136 * without modification. Used to disable the definition of strings
137 * (for example AVCodec long_names).
138 */
139 #if CONFIG_SMALL
140 # define NULL_IF_CONFIG_SMALL(x) NULL
141 #else
142 # define NULL_IF_CONFIG_SMALL(x) x
143 #endif
144
145
146 /**
147 * Define a function with only the non-default version specified.
148 *
149 * On systems with ELF shared libraries, all symbols exported from
150 * Libav libraries are tagged with the name and major version of the
151 * library to which they belong. If a function is moved from one
152 * library to another, a wrapper must be retained in the original
153 * location to preserve binary compatibility.
154 *
155 * Functions defined with this macro will never be used to resolve
156 * symbols by the build-time linker.
157 *
158 * @param type return type of function
159 * @param name name of function
160 * @param args argument list of function
161 * @param ver version tag to assign function
162 */
163 #if HAVE_SYMVER_ASM_LABEL
164 # define FF_SYMVER(type, name, args, ver) \
165 type ff_##name args __asm__ (EXTERN_PREFIX #name "@" ver); \
166 type ff_##name args
167 #elif HAVE_SYMVER_GNU_ASM
168 # define FF_SYMVER(type, name, args, ver) \
169 __asm__ (".symver ff_" #name "," EXTERN_PREFIX #name "@" ver); \
170 type ff_##name args; \
171 type ff_##name args
172 #endif
173
174 /**
175 * Return NULL if a threading library has not been enabled.
176 * Used to disable threading functions in AVCodec definitions
177 * when not needed.
178 */
179 #if HAVE_THREADS
180 # define ONLY_IF_THREADS_ENABLED(x) x
181 #else
182 # define ONLY_IF_THREADS_ENABLED(x) NULL
183 #endif
184
185 /**
186 * Log a generic warning message about a missing feature.
187 *
188 * @param[in] avc a pointer to an arbitrary struct of which the first
189 * field is a pointer to an AVClass struct
190 * @param[in] msg string containing the name of the missing feature
191 */
192 void avpriv_report_missing_feature(void *avc,
193 const char *msg, ...) av_printf_format(2, 3);
194
195 /**
196 * Log a generic warning message about a missing feature.
197 * Additionally request that a sample showcasing the feature be uploaded.
198 *
199 * @param[in] avc a pointer to an arbitrary struct of which the first field is
200 * a pointer to an AVClass struct
201 * @param[in] msg string containing the name of the missing feature
202 */
203 void avpriv_request_sample(void *avc,
204 const char *msg, ...) av_printf_format(2, 3);
205
206 #if HAVE_LIBC_MSVCRT
207 #define avpriv_open ff_open
208 #endif
209
210 /**
211 * A wrapper for open() setting O_CLOEXEC.
212 */
213 int avpriv_open(const char *filename, int flags, ...);
214
215 #endif /* AVUTIL_INTERNAL_H */