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internal.h
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1 /*
2  * copyright (c) 2006 Michael Niedermayer <michaelni@gmx.at>
3  *
4  * This file is part of FFmpeg.
5  *
6  * FFmpeg 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  * FFmpeg 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 FFmpeg; 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 "timer.h"
40 #include "cpu.h"
41 #include "dict.h"
42 #include "version.h"
43 
44 #if ARCH_X86
45 # include "x86/emms.h"
46 #endif
47 
48 #ifndef emms_c
49 # define emms_c()
50 #endif
51 
52 #ifndef attribute_align_arg
53 #if ARCH_X86_32 && AV_GCC_VERSION_AT_LEAST(4,2)
54 # define attribute_align_arg __attribute__((force_align_arg_pointer))
55 #else
56 # define attribute_align_arg
57 #endif
58 #endif
59 
60 #if defined(_MSC_VER) && CONFIG_SHARED
61 # define av_export __declspec(dllimport)
62 #else
63 # define av_export
64 #endif
65 
66 #if HAVE_PRAGMA_DEPRECATED
67 # if defined(__ICL) || defined (__INTEL_COMPILER)
68 # define FF_DISABLE_DEPRECATION_WARNINGS __pragma(warning(push)) __pragma(warning(disable:1478))
69 # define FF_ENABLE_DEPRECATION_WARNINGS __pragma(warning(pop))
70 # elif defined(_MSC_VER)
71 # define FF_DISABLE_DEPRECATION_WARNINGS __pragma(warning(push)) __pragma(warning(disable:4996))
72 # define FF_ENABLE_DEPRECATION_WARNINGS __pragma(warning(pop))
73 # else
74 # define FF_DISABLE_DEPRECATION_WARNINGS _Pragma("GCC diagnostic ignored \"-Wdeprecated-declarations\"")
75 # define FF_ENABLE_DEPRECATION_WARNINGS _Pragma("GCC diagnostic warning \"-Wdeprecated-declarations\"")
76 # endif
77 #else
78 # define FF_DISABLE_DEPRECATION_WARNINGS
79 # define FF_ENABLE_DEPRECATION_WARNINGS
80 #endif
81 
82 #ifndef INT_BIT
83 # define INT_BIT (CHAR_BIT * sizeof(int))
84 #endif
85 
86 #define FF_MEMORY_POISON 0x2a
87 
88 #define MAKE_ACCESSORS(str, name, type, field) \
89  type av_##name##_get_##field(const str *s) { return s->field; } \
90  void av_##name##_set_##field(str *s, type v) { s->field = v; }
91 
92 // Some broken preprocessors need a second expansion
93 // to be forced to tokenize __VA_ARGS__
94 #define E1(x) x
95 
96 #define LOCAL_ALIGNED_A(a, t, v, s, o, ...) \
97  uint8_t la_##v[sizeof(t s o) + (a)]; \
98  t (*v) o = (void *)FFALIGN((uintptr_t)la_##v, a)
99 
100 #define LOCAL_ALIGNED_D(a, t, v, s, o, ...) \
101  DECLARE_ALIGNED(a, t, la_##v) s o; \
102  t (*v) o = la_##v
103 
104 #define LOCAL_ALIGNED(a, t, v, ...) E1(LOCAL_ALIGNED_A(a, t, v, __VA_ARGS__,,))
105 
106 #if HAVE_LOCAL_ALIGNED_8
107 # define LOCAL_ALIGNED_8(t, v, ...) E1(LOCAL_ALIGNED_D(8, t, v, __VA_ARGS__,,))
108 #else
109 # define LOCAL_ALIGNED_8(t, v, ...) LOCAL_ALIGNED(8, t, v, __VA_ARGS__)
110 #endif
111 
112 #if HAVE_LOCAL_ALIGNED_16
113 # define LOCAL_ALIGNED_16(t, v, ...) E1(LOCAL_ALIGNED_D(16, t, v, __VA_ARGS__,,))
114 #else
115 # define LOCAL_ALIGNED_16(t, v, ...) LOCAL_ALIGNED(16, t, v, __VA_ARGS__)
116 #endif
117 
118 #define FF_ALLOC_OR_GOTO(ctx, p, size, label)\
119 {\
120  p = av_malloc(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 #define FF_ALLOCZ_OR_GOTO(ctx, p, size, label)\
128 {\
129  p = av_mallocz(size);\
130  if (p == NULL && (size) != 0) {\
131  av_log(ctx, AV_LOG_ERROR, "Cannot allocate memory.\n");\
132  goto label;\
133  }\
134 }
135 
136 #include "libm.h"
137 
138 #if defined(_MSC_VER)
139 #pragma comment(linker, "/include:"EXTERN_PREFIX"avpriv_strtod")
140 #pragma comment(linker, "/include:"EXTERN_PREFIX"avpriv_snprintf")
141 #endif
142 
143 /**
144  * Return NULL if CONFIG_SMALL is true, otherwise the argument
145  * without modification. Used to disable the definition of strings
146  * (for example AVCodec long_names).
147  */
148 #if CONFIG_SMALL
149 # define NULL_IF_CONFIG_SMALL(x) NULL
150 #else
151 # define NULL_IF_CONFIG_SMALL(x) x
152 #endif
153 
154 /**
155  * Define a function with only the non-default version specified.
156  *
157  * On systems with ELF shared libraries, all symbols exported from
158  * FFmpeg libraries are tagged with the name and major version of the
159  * library to which they belong. If a function is moved from one
160  * library to another, a wrapper must be retained in the original
161  * location to preserve binary compatibility.
162  *
163  * Functions defined with this macro will never be used to resolve
164  * symbols by the build-time linker.
165  *
166  * @param type return type of function
167  * @param name name of function
168  * @param args argument list of function
169  * @param ver version tag to assign function
170  */
171 #if HAVE_SYMVER_ASM_LABEL
172 # define FF_SYMVER(type, name, args, ver) \
173  type ff_##name args __asm__ (EXTERN_PREFIX #name "@" ver); \
174  type ff_##name args
175 #elif HAVE_SYMVER_GNU_ASM
176 # define FF_SYMVER(type, name, args, ver) \
177  __asm__ (".symver ff_" #name "," EXTERN_PREFIX #name "@" ver); \
178  type ff_##name args; \
179  type ff_##name args
180 #endif
181 
182 /**
183  * Return NULL if a threading library has not been enabled.
184  * Used to disable threading functions in AVCodec definitions
185  * when not needed.
186  */
187 #if HAVE_THREADS
188 # define ONLY_IF_THREADS_ENABLED(x) x
189 #else
190 # define ONLY_IF_THREADS_ENABLED(x) NULL
191 #endif
192 
193 /**
194  * Log a generic warning message about a missing feature.
195  *
196  * @param[in] avc a pointer to an arbitrary struct of which the first
197  * field is a pointer to an AVClass struct
198  * @param[in] msg string containing the name of the missing feature
199  */
200 void avpriv_report_missing_feature(void *avc,
201  const char *msg, ...) av_printf_format(2, 3);
202 
203 /**
204  * Log a generic warning message about a missing feature.
205  * Additionally request that a sample showcasing the feature be uploaded.
206  *
207  * @param[in] avc a pointer to an arbitrary struct of which the first field is
208  * a pointer to an AVClass struct
209  * @param[in] msg string containing the name of the missing feature
210  */
211 void avpriv_request_sample(void *avc,
212  const char *msg, ...) av_printf_format(2, 3);
213 
214 #if HAVE_LIBC_MSVCRT
215 #define avpriv_open ff_open
216 #endif
217 
218 /**
219  * A wrapper for open() setting O_CLOEXEC.
220  */
221 int avpriv_open(const char *filename, int flags, ...);
222 
223 #if FF_API_GET_CHANNEL_LAYOUT_COMPAT
224 uint64_t ff_get_channel_layout(const char *name, int compat);
225 #endif
226 
227 #endif /* AVUTIL_INTERNAL_H */