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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 
84 #define FF_MEMORY_POISON 0x2a
85 
86 #define MAKE_ACCESSORS(str, name, type, field) \
87  type av_##name##_get_##field(const str *s) { return s->field; } \
88  void av_##name##_set_##field(str *s, type v) { s->field = v; }
89 
90 // Some broken preprocessors need a second expansion
91 // to be forced to tokenize __VA_ARGS__
92 #define E1(x) x
93 
94 /* Check if the hard coded offset of a struct member still matches reality.
95  * Induce a compilation failure if not.
96  */
97 #define AV_CHECK_OFFSET(s, m, o) struct check_##o { \
98  int x_##o[offsetof(s, m) == o? 1: -1]; \
99  }
100 
101 #define LOCAL_ALIGNED_A(a, t, v, s, o, ...) \
102  uint8_t la_##v[sizeof(t s o) + (a)]; \
103  t (*v) o = (void *)FFALIGN((uintptr_t)la_##v, a)
104 
105 #define LOCAL_ALIGNED_D(a, t, v, s, o, ...) \
106  DECLARE_ALIGNED(a, t, la_##v) s o; \
107  t (*v) o = la_##v
108 
109 #define LOCAL_ALIGNED(a, t, v, ...) E1(LOCAL_ALIGNED_A(a, t, v, __VA_ARGS__,,))
110 
111 #if HAVE_LOCAL_ALIGNED_8
112 # define LOCAL_ALIGNED_8(t, v, ...) E1(LOCAL_ALIGNED_D(8, t, v, __VA_ARGS__,,))
113 #else
114 # define LOCAL_ALIGNED_8(t, v, ...) LOCAL_ALIGNED(8, t, v, __VA_ARGS__)
115 #endif
116 
117 #if HAVE_LOCAL_ALIGNED_16
118 # define LOCAL_ALIGNED_16(t, v, ...) E1(LOCAL_ALIGNED_D(16, t, v, __VA_ARGS__,,))
119 #else
120 # define LOCAL_ALIGNED_16(t, v, ...) LOCAL_ALIGNED(16, t, v, __VA_ARGS__)
121 #endif
122 
123 #if HAVE_LOCAL_ALIGNED_32
124 # define LOCAL_ALIGNED_32(t, v, ...) E1(LOCAL_ALIGNED_D(32, t, v, __VA_ARGS__,,))
125 #else
126 # define LOCAL_ALIGNED_32(t, v, ...) LOCAL_ALIGNED(32, t, v, __VA_ARGS__)
127 #endif
128 
129 #define FF_ALLOC_OR_GOTO(ctx, p, size, label)\
130 {\
131  p = av_malloc(size);\
132  if (!(p) && (size) != 0) {\
133  av_log(ctx, AV_LOG_ERROR, "Cannot allocate memory.\n");\
134  goto label;\
135  }\
136 }
137 
138 #define FF_ALLOCZ_OR_GOTO(ctx, p, size, label)\
139 {\
140  p = av_mallocz(size);\
141  if (!(p) && (size) != 0) {\
142  av_log(ctx, AV_LOG_ERROR, "Cannot allocate memory.\n");\
143  goto label;\
144  }\
145 }
146 
147 #define FF_ALLOC_ARRAY_OR_GOTO(ctx, p, nelem, elsize, label)\
148 {\
149  p = av_malloc_array(nelem, elsize);\
150  if (!p) {\
151  av_log(ctx, AV_LOG_ERROR, "Cannot allocate memory.\n");\
152  goto label;\
153  }\
154 }
155 
156 #define FF_ALLOCZ_ARRAY_OR_GOTO(ctx, p, nelem, elsize, label)\
157 {\
158  p = av_mallocz_array(nelem, elsize);\
159  if (!p) {\
160  av_log(ctx, AV_LOG_ERROR, "Cannot allocate memory.\n");\
161  goto label;\
162  }\
163 }
164 
165 #include "libm.h"
166 
167 #if defined(_MSC_VER) && _MSC_VER < 1900
168 #pragma comment(linker, "/include:"EXTERN_PREFIX"avpriv_strtod")
169 #pragma comment(linker, "/include:"EXTERN_PREFIX"avpriv_snprintf")
170 #endif
171 
172 /**
173  * Return NULL if CONFIG_SMALL is true, otherwise the argument
174  * without modification. Used to disable the definition of strings
175  * (for example AVCodec long_names).
176  */
177 #if CONFIG_SMALL
178 # define NULL_IF_CONFIG_SMALL(x) NULL
179 #else
180 # define NULL_IF_CONFIG_SMALL(x) x
181 #endif
182 
183 /**
184  * Define a function with only the non-default version specified.
185  *
186  * On systems with ELF shared libraries, all symbols exported from
187  * FFmpeg libraries are tagged with the name and major version of the
188  * library to which they belong. If a function is moved from one
189  * library to another, a wrapper must be retained in the original
190  * location to preserve binary compatibility.
191  *
192  * Functions defined with this macro will never be used to resolve
193  * symbols by the build-time linker.
194  *
195  * @param type return type of function
196  * @param name name of function
197  * @param args argument list of function
198  * @param ver version tag to assign function
199  */
200 #if HAVE_SYMVER_ASM_LABEL
201 # define FF_SYMVER(type, name, args, ver) \
202  type ff_##name args __asm__ (EXTERN_PREFIX #name "@" ver); \
203  type ff_##name args
204 #elif HAVE_SYMVER_GNU_ASM
205 # define FF_SYMVER(type, name, args, ver) \
206  __asm__ (".symver ff_" #name "," EXTERN_PREFIX #name "@" ver); \
207  type ff_##name args; \
208  type ff_##name args
209 #endif
210 
211 /**
212  * Return NULL if a threading library has not been enabled.
213  * Used to disable threading functions in AVCodec definitions
214  * when not needed.
215  */
216 #if HAVE_THREADS
217 # define ONLY_IF_THREADS_ENABLED(x) x
218 #else
219 # define ONLY_IF_THREADS_ENABLED(x) NULL
220 #endif
221 
222 /**
223  * Log a generic warning message about a missing feature.
224  *
225  * @param[in] avc a pointer to an arbitrary struct of which the first
226  * field is a pointer to an AVClass struct
227  * @param[in] msg string containing the name of the missing feature
228  */
229 void avpriv_report_missing_feature(void *avc,
230  const char *msg, ...) av_printf_format(2, 3);
231 
232 /**
233  * Log a generic warning message about a missing feature.
234  * Additionally request that a sample showcasing the feature be uploaded.
235  *
236  * @param[in] avc a pointer to an arbitrary struct of which the first field is
237  * a pointer to an AVClass struct
238  * @param[in] msg string containing the name of the missing feature
239  */
240 void avpriv_request_sample(void *avc,
241  const char *msg, ...) av_printf_format(2, 3);
242 
243 #if HAVE_LIBC_MSVCRT
244 #define avpriv_open ff_open
245 #define PTRDIFF_SPECIFIER "Id"
246 #define SIZE_SPECIFIER "Iu"
247 #else
248 #define PTRDIFF_SPECIFIER "td"
249 #define SIZE_SPECIFIER "zu"
250 #endif
251 
252 /**
253  * A wrapper for open() setting O_CLOEXEC.
254  */
255 int avpriv_open(const char *filename, int flags, ...);
256 
257 int avpriv_set_systematic_pal2(uint32_t pal[256], enum AVPixelFormat pix_fmt);
258 
259 static av_always_inline av_const int avpriv_mirror(int x, int w)
260 {
261  if (!w)
262  return 0;
263 
264  while ((unsigned)x > (unsigned)w) {
265  x = -x;
266  if (x < 0)
267  x += 2 * w;
268  }
269  return x;
270 }
271 
272 #if FF_API_GET_CHANNEL_LAYOUT_COMPAT
273 uint64_t ff_get_channel_layout(const char *name, int compat);
274 #endif
275 
276 void ff_check_pixfmt_descriptors(void);
277 
278 #endif /* AVUTIL_INTERNAL_H */