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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 "pixfmt.h"
43 #include "version.h"
44 
45 #if ARCH_X86
46 # include "x86/emms.h"
47 #endif
48 
49 #ifndef emms_c
50 # define emms_c()
51 #endif
52 
53 #ifndef attribute_align_arg
54 #if ARCH_X86_32 && AV_GCC_VERSION_AT_LEAST(4,2)
55 # define attribute_align_arg __attribute__((force_align_arg_pointer))
56 #else
57 # define attribute_align_arg
58 #endif
59 #endif
60 
61 #if defined(_MSC_VER) && CONFIG_SHARED
62 # define av_export __declspec(dllimport)
63 #else
64 # define av_export
65 #endif
66 
67 #if HAVE_PRAGMA_DEPRECATED
68 # if defined(__ICL) || defined (__INTEL_COMPILER)
69 # define FF_DISABLE_DEPRECATION_WARNINGS __pragma(warning(push)) __pragma(warning(disable:1478))
70 # define FF_ENABLE_DEPRECATION_WARNINGS __pragma(warning(pop))
71 # elif defined(_MSC_VER)
72 # define FF_DISABLE_DEPRECATION_WARNINGS __pragma(warning(push)) __pragma(warning(disable:4996))
73 # define FF_ENABLE_DEPRECATION_WARNINGS __pragma(warning(pop))
74 # else
75 # define FF_DISABLE_DEPRECATION_WARNINGS _Pragma("GCC diagnostic ignored \"-Wdeprecated-declarations\"")
76 # define FF_ENABLE_DEPRECATION_WARNINGS _Pragma("GCC diagnostic warning \"-Wdeprecated-declarations\"")
77 # endif
78 #else
79 # define FF_DISABLE_DEPRECATION_WARNINGS
80 # define FF_ENABLE_DEPRECATION_WARNINGS
81 #endif
82 
83 #ifndef INT_BIT
84 # define INT_BIT (CHAR_BIT * sizeof(int))
85 #endif
86 
87 #define FF_MEMORY_POISON 0x2a
88 
89 #define MAKE_ACCESSORS(str, name, type, field) \
90  type av_##name##_get_##field(const str *s) { return s->field; } \
91  void av_##name##_set_##field(str *s, type v) { s->field = v; }
92 
93 // Some broken preprocessors need a second expansion
94 // to be forced to tokenize __VA_ARGS__
95 #define E1(x) x
96 
97 /* Check if the hard coded offset of a struct member still matches reality.
98  * Induce a compilation failure if not.
99  */
100 #define AV_CHECK_OFFSET(s, m, o) struct check_##o { \
101  int x_##o[offsetof(s, m) == o? 1: -1]; \
102  }
103 
104 #define LOCAL_ALIGNED_A(a, t, v, s, o, ...) \
105  uint8_t la_##v[sizeof(t s o) + (a)]; \
106  t (*v) o = (void *)FFALIGN((uintptr_t)la_##v, a)
107 
108 #define LOCAL_ALIGNED_D(a, t, v, s, o, ...) \
109  DECLARE_ALIGNED(a, t, la_##v) s o; \
110  t (*v) o = la_##v
111 
112 #define LOCAL_ALIGNED(a, t, v, ...) E1(LOCAL_ALIGNED_A(a, t, v, __VA_ARGS__,,))
113 
114 #if HAVE_LOCAL_ALIGNED_8
115 # define LOCAL_ALIGNED_8(t, v, ...) E1(LOCAL_ALIGNED_D(8, t, v, __VA_ARGS__,,))
116 #else
117 # define LOCAL_ALIGNED_8(t, v, ...) LOCAL_ALIGNED(8, t, v, __VA_ARGS__)
118 #endif
119 
120 #if HAVE_LOCAL_ALIGNED_16
121 # define LOCAL_ALIGNED_16(t, v, ...) E1(LOCAL_ALIGNED_D(16, t, v, __VA_ARGS__,,))
122 #else
123 # define LOCAL_ALIGNED_16(t, v, ...) LOCAL_ALIGNED(16, t, v, __VA_ARGS__)
124 #endif
125 
126 #if HAVE_LOCAL_ALIGNED_32
127 # define LOCAL_ALIGNED_32(t, v, ...) E1(LOCAL_ALIGNED_D(32, t, v, __VA_ARGS__,,))
128 #else
129 # define LOCAL_ALIGNED_32(t, v, ...) LOCAL_ALIGNED(32, t, v, __VA_ARGS__)
130 #endif
131 
132 #define FF_ALLOC_OR_GOTO(ctx, p, size, label)\
133 {\
134  p = av_malloc(size);\
135  if (!(p) && (size) != 0) {\
136  av_log(ctx, AV_LOG_ERROR, "Cannot allocate memory.\n");\
137  goto label;\
138  }\
139 }
140 
141 #define FF_ALLOCZ_OR_GOTO(ctx, p, size, label)\
142 {\
143  p = av_mallocz(size);\
144  if (!(p) && (size) != 0) {\
145  av_log(ctx, AV_LOG_ERROR, "Cannot allocate memory.\n");\
146  goto label;\
147  }\
148 }
149 
150 #define FF_ALLOC_ARRAY_OR_GOTO(ctx, p, nelem, elsize, label)\
151 {\
152  p = av_malloc_array(nelem, elsize);\
153  if (!p) {\
154  av_log(ctx, AV_LOG_ERROR, "Cannot allocate memory.\n");\
155  goto label;\
156  }\
157 }
158 
159 #define FF_ALLOCZ_ARRAY_OR_GOTO(ctx, p, nelem, elsize, label)\
160 {\
161  p = av_mallocz_array(nelem, elsize);\
162  if (!p) {\
163  av_log(ctx, AV_LOG_ERROR, "Cannot allocate memory.\n");\
164  goto label;\
165  }\
166 }
167 
168 #include "libm.h"
169 
170 #if defined(_MSC_VER)
171 #pragma comment(linker, "/include:"EXTERN_PREFIX"avpriv_strtod")
172 #pragma comment(linker, "/include:"EXTERN_PREFIX"avpriv_snprintf")
173 #endif
174 
175 /**
176  * Return NULL if CONFIG_SMALL is true, otherwise the argument
177  * without modification. Used to disable the definition of strings
178  * (for example AVCodec long_names).
179  */
180 #if CONFIG_SMALL
181 # define NULL_IF_CONFIG_SMALL(x) NULL
182 #else
183 # define NULL_IF_CONFIG_SMALL(x) x
184 #endif
185 
186 /**
187  * Define a function with only the non-default version specified.
188  *
189  * On systems with ELF shared libraries, all symbols exported from
190  * FFmpeg libraries are tagged with the name and major version of the
191  * library to which they belong. If a function is moved from one
192  * library to another, a wrapper must be retained in the original
193  * location to preserve binary compatibility.
194  *
195  * Functions defined with this macro will never be used to resolve
196  * symbols by the build-time linker.
197  *
198  * @param type return type of function
199  * @param name name of function
200  * @param args argument list of function
201  * @param ver version tag to assign function
202  */
203 #if HAVE_SYMVER_ASM_LABEL
204 # define FF_SYMVER(type, name, args, ver) \
205  type ff_##name args __asm__ (EXTERN_PREFIX #name "@" ver); \
206  type ff_##name args
207 #elif HAVE_SYMVER_GNU_ASM
208 # define FF_SYMVER(type, name, args, ver) \
209  __asm__ (".symver ff_" #name "," EXTERN_PREFIX #name "@" ver); \
210  type ff_##name args; \
211  type ff_##name args
212 #endif
213 
214 /**
215  * Return NULL if a threading library has not been enabled.
216  * Used to disable threading functions in AVCodec definitions
217  * when not needed.
218  */
219 #if HAVE_THREADS
220 # define ONLY_IF_THREADS_ENABLED(x) x
221 #else
222 # define ONLY_IF_THREADS_ENABLED(x) NULL
223 #endif
224 
225 /**
226  * Log a generic warning message about a missing feature.
227  *
228  * @param[in] avc a pointer to an arbitrary struct of which the first
229  * field is a pointer to an AVClass struct
230  * @param[in] msg string containing the name of the missing feature
231  */
232 void avpriv_report_missing_feature(void *avc,
233  const char *msg, ...) av_printf_format(2, 3);
234 
235 /**
236  * Log a generic warning message about a missing feature.
237  * Additionally request that a sample showcasing the feature be uploaded.
238  *
239  * @param[in] avc a pointer to an arbitrary struct of which the first field is
240  * a pointer to an AVClass struct
241  * @param[in] msg string containing the name of the missing feature
242  */
243 void avpriv_request_sample(void *avc,
244  const char *msg, ...) av_printf_format(2, 3);
245 
246 #if HAVE_LIBC_MSVCRT
247 #define avpriv_open ff_open
248 #define PTRDIFF_SPECIFIER "Id"
249 #define SIZE_SPECIFIER "Iu"
250 #else
251 #define PTRDIFF_SPECIFIER "td"
252 #define SIZE_SPECIFIER "zu"
253 #endif
254 
255 /**
256  * A wrapper for open() setting O_CLOEXEC.
257  */
258 int avpriv_open(const char *filename, int flags, ...);
259 
260 int avpriv_set_systematic_pal2(uint32_t pal[256], enum AVPixelFormat pix_fmt);
261 
262 #if FF_API_GET_CHANNEL_LAYOUT_COMPAT
263 uint64_t ff_get_channel_layout(const char *name, int compat);
264 #endif
265 
266 #endif /* AVUTIL_INTERNAL_H */