FFmpeg  2.8.15
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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 // This can be enabled to allow detection of additional integer overflows with ubsan
34 //#define CHECKED
35 
36 #include <limits.h>
37 #include <stdint.h>
38 #include <stddef.h>
39 #include <assert.h>
40 #include "config.h"
41 #include "attributes.h"
42 #include "timer.h"
43 #include "cpu.h"
44 #include "dict.h"
45 #include "pixfmt.h"
46 #include "version.h"
47 
48 #if ARCH_X86
49 # include "x86/emms.h"
50 #endif
51 
52 #ifndef emms_c
53 # define emms_c() while(0)
54 #endif
55 
56 #ifndef attribute_align_arg
57 #if ARCH_X86_32 && AV_GCC_VERSION_AT_LEAST(4,2)
58 # define attribute_align_arg __attribute__((force_align_arg_pointer))
59 #else
60 # define attribute_align_arg
61 #endif
62 #endif
63 
64 #if defined(_MSC_VER) && CONFIG_SHARED
65 # define av_export __declspec(dllimport)
66 #else
67 # define av_export
68 #endif
69 
70 #if HAVE_PRAGMA_DEPRECATED
71 # if defined(__ICL) || defined (__INTEL_COMPILER)
72 # define FF_DISABLE_DEPRECATION_WARNINGS __pragma(warning(push)) __pragma(warning(disable:1478))
73 # define FF_ENABLE_DEPRECATION_WARNINGS __pragma(warning(pop))
74 # elif defined(_MSC_VER)
75 # define FF_DISABLE_DEPRECATION_WARNINGS __pragma(warning(push)) __pragma(warning(disable:4996))
76 # define FF_ENABLE_DEPRECATION_WARNINGS __pragma(warning(pop))
77 # else
78 # define FF_DISABLE_DEPRECATION_WARNINGS _Pragma("GCC diagnostic ignored \"-Wdeprecated-declarations\"")
79 # define FF_ENABLE_DEPRECATION_WARNINGS _Pragma("GCC diagnostic warning \"-Wdeprecated-declarations\"")
80 # endif
81 #else
82 # define FF_DISABLE_DEPRECATION_WARNINGS
83 # define FF_ENABLE_DEPRECATION_WARNINGS
84 #endif
85 
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 /**
171  * Return NULL if CONFIG_SMALL is true, otherwise the argument
172  * without modification. Used to disable the definition of strings
173  * (for example AVCodec long_names).
174  */
175 #if CONFIG_SMALL
176 # define NULL_IF_CONFIG_SMALL(x) NULL
177 #else
178 # define NULL_IF_CONFIG_SMALL(x) x
179 #endif
180 
181 /**
182  * Define a function with only the non-default version specified.
183  *
184  * On systems with ELF shared libraries, all symbols exported from
185  * FFmpeg libraries are tagged with the name and major version of the
186  * library to which they belong. If a function is moved from one
187  * library to another, a wrapper must be retained in the original
188  * location to preserve binary compatibility.
189  *
190  * Functions defined with this macro will never be used to resolve
191  * symbols by the build-time linker.
192  *
193  * @param type return type of function
194  * @param name name of function
195  * @param args argument list of function
196  * @param ver version tag to assign function
197  */
198 #if HAVE_SYMVER_ASM_LABEL
199 # define FF_SYMVER(type, name, args, ver) \
200  type ff_##name args __asm__ (EXTERN_PREFIX #name "@" ver); \
201  type ff_##name args
202 #elif HAVE_SYMVER_GNU_ASM
203 # define FF_SYMVER(type, name, args, ver) \
204  __asm__ (".symver ff_" #name "," EXTERN_PREFIX #name "@" ver); \
205  type ff_##name args; \
206  type ff_##name args
207 #endif
208 
209 /**
210  * Return NULL if a threading library has not been enabled.
211  * Used to disable threading functions in AVCodec definitions
212  * when not needed.
213  */
214 #if HAVE_THREADS
215 # define ONLY_IF_THREADS_ENABLED(x) x
216 #else
217 # define ONLY_IF_THREADS_ENABLED(x) NULL
218 #endif
219 
220 /**
221  * Log a generic warning message about a missing feature.
222  *
223  * @param[in] avc a pointer to an arbitrary struct of which the first
224  * field is a pointer to an AVClass struct
225  * @param[in] msg string containing the name of the missing feature
226  */
227 void avpriv_report_missing_feature(void *avc,
228  const char *msg, ...) av_printf_format(2, 3);
229 
230 /**
231  * Log a generic warning message about a missing feature.
232  * Additionally request that a sample showcasing the feature be uploaded.
233  *
234  * @param[in] avc a pointer to an arbitrary struct of which the first field is
235  * a pointer to an AVClass struct
236  * @param[in] msg string containing the name of the missing feature
237  */
238 void avpriv_request_sample(void *avc,
239  const char *msg, ...) av_printf_format(2, 3);
240 
241 #if HAVE_LIBC_MSVCRT
242 #include <crtversion.h>
243 #if defined(_VC_CRT_MAJOR_VERSION) && _VC_CRT_MAJOR_VERSION < 14
244 #pragma comment(linker, "/include:" EXTERN_PREFIX "avpriv_strtod")
245 #pragma comment(linker, "/include:" EXTERN_PREFIX "avpriv_snprintf")
246 #endif
247 
248 #define avpriv_open ff_open
249 #define PTRDIFF_SPECIFIER "Id"
250 #define SIZE_SPECIFIER "Iu"
251 #else
252 #define PTRDIFF_SPECIFIER "td"
253 #define SIZE_SPECIFIER "zu"
254 #endif
255 
256 #ifdef DEBUG
257 # define ff_dlog(ctx, ...) av_log(ctx, AV_LOG_DEBUG, __VA_ARGS__)
258 #else
259 # define ff_dlog(ctx, ...) do { if (0) av_log(ctx, AV_LOG_DEBUG, __VA_ARGS__); } while (0)
260 #endif
261 
262 // For debuging we use signed operations so overflows can be detected (by ubsan)
263 // For production we use unsigned so there are no undefined operations
264 #ifdef CHECKED
265 #define SUINT int
266 #define SUINT32 int32_t
267 #else
268 #define SUINT unsigned
269 #define SUINT32 uint32_t
270 #endif
271 
272 /**
273  * A wrapper for open() setting O_CLOEXEC.
274  */
275 int avpriv_open(const char *filename, int flags, ...);
276 
277 int avpriv_set_systematic_pal2(uint32_t pal[256], enum AVPixelFormat pix_fmt);
278 
279 static av_always_inline av_const int avpriv_mirror(int x, int w)
280 {
281  if (!w)
282  return 0;
283 
284  while ((unsigned)x > (unsigned)w) {
285  x = -x;
286  if (x < 0)
287  x += 2 * w;
288  }
289  return x;
290 }
291 
292 #if FF_API_GET_CHANNEL_LAYOUT_COMPAT
293 uint64_t ff_get_channel_layout(const char *name, int compat);
294 #endif
295 
296 void ff_check_pixfmt_descriptors(void);
297 
298 extern const uint8_t ff_reverse[256];
299 
300 #endif /* AVUTIL_INTERNAL_H */
#define av_const
Definition: attributes.h:68
static enum AVPixelFormat pix_fmt
Macro definitions for various function/variable attributes.
Public dictionary API.
void void avpriv_request_sample(void *avc, const char *msg,...) av_printf_format(2
Log a generic warning message about a missing feature.
uint8_t
high precision timer, useful to profile code
const uint8_t ff_reverse[256]
Definition: reverse.c:23
Libavutil version macros.
#define av_printf_format(fmtpos, attrpos)
Definition: attributes.h:148
static av_always_inline av_const int avpriv_mirror(int x, int w)
Definition: internal.h:279
Replacements for frequently missing libm functions.
int avpriv_open(const char *filename, int flags,...)
A wrapper for open() setting O_CLOEXEC.
Definition: file_open.c:66
void avpriv_report_missing_feature(void *avc, const char *msg,...) av_printf_format(2
Log a generic warning message about a missing feature.
static int flags
Definition: cpu.c:47
void ff_check_pixfmt_descriptors(void)
Definition: pixdesc.c:2184
uint64_t ff_get_channel_layout(const char *name, int compat)
pixel format definitions
int avpriv_set_systematic_pal2(uint32_t pal[256], enum AVPixelFormat pix_fmt)
Definition: imgutils.c:152
#define av_always_inline
Definition: attributes.h:37
AVPixelFormat
Pixel format.
Definition: pixfmt.h:61
const char * name
Definition: opengl_enc.c:103