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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 #if defined(DEBUG) && !defined(CHECKED)
34 # define CHECKED
35 #endif
36 
37 #include <limits.h>
38 #include <stdint.h>
39 #include <stddef.h>
40 #include <assert.h>
41 #include "config.h"
42 #include "attributes.h"
43 #include "timer.h"
44 #include "cpu.h"
45 #include "dict.h"
46 #include "macros.h"
47 #include "pixfmt.h"
48 #include "version.h"
49 
50 #if ARCH_X86
51 # include "x86/emms.h"
52 #endif
53 
54 #ifndef emms_c
55 # define emms_c() while(0)
56 #endif
57 
58 #ifndef attribute_align_arg
59 #if ARCH_X86_32 && AV_GCC_VERSION_AT_LEAST(4,2)
60 # define attribute_align_arg __attribute__((force_align_arg_pointer))
61 #else
62 # define attribute_align_arg
63 #endif
64 #endif
65 
66 #if defined(_MSC_VER) && CONFIG_SHARED
67 # define av_export __declspec(dllimport)
68 #else
69 # define av_export
70 #endif
71 
72 #if HAVE_PRAGMA_DEPRECATED
73 # if defined(__ICL) || defined (__INTEL_COMPILER)
74 # define FF_DISABLE_DEPRECATION_WARNINGS __pragma(warning(push)) __pragma(warning(disable:1478))
75 # define FF_ENABLE_DEPRECATION_WARNINGS __pragma(warning(pop))
76 # elif defined(_MSC_VER)
77 # define FF_DISABLE_DEPRECATION_WARNINGS __pragma(warning(push)) __pragma(warning(disable:4996))
78 # define FF_ENABLE_DEPRECATION_WARNINGS __pragma(warning(pop))
79 # else
80 # define FF_DISABLE_DEPRECATION_WARNINGS _Pragma("GCC diagnostic ignored \"-Wdeprecated-declarations\"")
81 # define FF_ENABLE_DEPRECATION_WARNINGS _Pragma("GCC diagnostic warning \"-Wdeprecated-declarations\"")
82 # endif
83 #else
84 # define FF_DISABLE_DEPRECATION_WARNINGS
85 # define FF_ENABLE_DEPRECATION_WARNINGS
86 #endif
87 
88 
89 #define FF_MEMORY_POISON 0x2a
90 
91 #define MAKE_ACCESSORS(str, name, type, field) \
92  type av_##name##_get_##field(const str *s) { return s->field; } \
93  void av_##name##_set_##field(str *s, type v) { s->field = v; }
94 
95 // Some broken preprocessors need a second expansion
96 // to be forced to tokenize __VA_ARGS__
97 #define E1(x) x
98 
99 /* Check if the hard coded offset of a struct member still matches reality.
100  * Induce a compilation failure if not.
101  */
102 #define AV_CHECK_OFFSET(s, m, o) struct check_##o { \
103  int x_##o[offsetof(s, m) == o? 1: -1]; \
104  }
105 
106 #define LOCAL_ALIGNED_A(a, t, v, s, o, ...) \
107  uint8_t la_##v[sizeof(t s o) + (a)]; \
108  t (*v) o = (void *)FFALIGN((uintptr_t)la_##v, a)
109 
110 #define LOCAL_ALIGNED_D(a, t, v, s, o, ...) \
111  DECLARE_ALIGNED(a, t, la_##v) s o; \
112  t (*v) o = la_##v
113 
114 #define LOCAL_ALIGNED(a, t, v, ...) E1(LOCAL_ALIGNED_A(a, t, v, __VA_ARGS__,,))
115 
116 #if HAVE_LOCAL_ALIGNED_8
117 # define LOCAL_ALIGNED_8(t, v, ...) E1(LOCAL_ALIGNED_D(8, t, v, __VA_ARGS__,,))
118 #else
119 # define LOCAL_ALIGNED_8(t, v, ...) LOCAL_ALIGNED(8, t, v, __VA_ARGS__)
120 #endif
121 
122 #if HAVE_LOCAL_ALIGNED_16
123 # define LOCAL_ALIGNED_16(t, v, ...) E1(LOCAL_ALIGNED_D(16, t, v, __VA_ARGS__,,))
124 #else
125 # define LOCAL_ALIGNED_16(t, v, ...) LOCAL_ALIGNED(16, t, v, __VA_ARGS__)
126 #endif
127 
128 #if HAVE_LOCAL_ALIGNED_32
129 # define LOCAL_ALIGNED_32(t, v, ...) E1(LOCAL_ALIGNED_D(32, t, v, __VA_ARGS__,,))
130 #else
131 # define LOCAL_ALIGNED_32(t, v, ...) LOCAL_ALIGNED(32, t, v, __VA_ARGS__)
132 #endif
133 
134 #define FF_ALLOC_OR_GOTO(ctx, p, size, label)\
135 {\
136  p = av_malloc(size);\
137  if (!(p) && (size) != 0) {\
138  av_log(ctx, AV_LOG_ERROR, "Cannot allocate memory.\n");\
139  goto label;\
140  }\
141 }
142 
143 #define FF_ALLOCZ_OR_GOTO(ctx, p, size, label)\
144 {\
145  p = av_mallocz(size);\
146  if (!(p) && (size) != 0) {\
147  av_log(ctx, AV_LOG_ERROR, "Cannot allocate memory.\n");\
148  goto label;\
149  }\
150 }
151 
152 #define FF_ALLOC_ARRAY_OR_GOTO(ctx, p, nelem, elsize, label)\
153 {\
154  p = av_malloc_array(nelem, elsize);\
155  if (!p) {\
156  av_log(ctx, AV_LOG_ERROR, "Cannot allocate memory.\n");\
157  goto label;\
158  }\
159 }
160 
161 #define FF_ALLOCZ_ARRAY_OR_GOTO(ctx, p, nelem, elsize, label)\
162 {\
163  p = av_mallocz_array(nelem, elsize);\
164  if (!p) {\
165  av_log(ctx, AV_LOG_ERROR, "Cannot allocate memory.\n");\
166  goto label;\
167  }\
168 }
169 
170 #include "libm.h"
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 #include <crtversion.h>
245 #if defined(_VC_CRT_MAJOR_VERSION) && _VC_CRT_MAJOR_VERSION < 14
246 #pragma comment(linker, "/include:" EXTERN_PREFIX "avpriv_strtod")
247 #pragma comment(linker, "/include:" EXTERN_PREFIX "avpriv_snprintf")
248 #endif
249 
250 #define avpriv_open ff_open
251 #define avpriv_tempfile ff_tempfile
252 #define PTRDIFF_SPECIFIER "Id"
253 #define SIZE_SPECIFIER "Iu"
254 #else
255 #define PTRDIFF_SPECIFIER "td"
256 #define SIZE_SPECIFIER "zu"
257 #endif
258 
259 #ifdef DEBUG
260 # define ff_dlog(ctx, ...) av_log(ctx, AV_LOG_DEBUG, __VA_ARGS__)
261 #else
262 # define ff_dlog(ctx, ...) do { if (0) av_log(ctx, AV_LOG_DEBUG, __VA_ARGS__); } while (0)
263 #endif
264 
265 // For debuging we use signed operations so overflows can be detected (by ubsan)
266 // For production we use unsigned so there are no undefined operations
267 #ifdef CHECKED
268 #define SUINT int
269 #define SUINT32 int32_t
270 #else
271 #define SUINT unsigned
272 #define SUINT32 uint32_t
273 #endif
274 
275 /**
276  * Clip and convert a double value into the long long amin-amax range.
277  * This function is needed because conversion of floating point to integers when
278  * it does not fit in the integer's representation does not necessarily saturate
279  * correctly (usually converted to a cvttsd2si on x86) which saturates numbers
280  * > INT64_MAX to INT64_MIN. The standard marks such conversions as undefined
281  * behavior, allowing this sort of mathematically bogus conversions. This provides
282  * a safe alternative that is slower obviously but assures safety and better
283  * mathematical behavior.
284  * @param a value to clip
285  * @param amin minimum value of the clip range
286  * @param amax maximum value of the clip range
287  * @return clipped value
288  */
289 static av_always_inline av_const int64_t ff_rint64_clip(double a, int64_t amin, int64_t amax)
290 {
291  int64_t res;
292 #if defined(HAVE_AV_CONFIG_H) && defined(ASSERT_LEVEL) && ASSERT_LEVEL >= 2
293  if (amin > amax) abort();
294 #endif
295  // INT64_MAX+1,INT64_MIN are exactly representable as IEEE doubles
296  // do range checks first
297  if (a >= 9223372036854775808.0)
298  return amax;
299  if (a <= -9223372036854775808.0)
300  return amin;
301 
302  // safe to call llrint and clip accordingly
303  res = llrint(a);
304  if (res > amax)
305  return amax;
306  if (res < amin)
307  return amin;
308  return res;
309 }
310 
311 /**
312  * A wrapper for open() setting O_CLOEXEC.
313  */
315 int avpriv_open(const char *filename, int flags, ...);
316 
317 /**
318  * Wrapper to work around the lack of mkstemp() on mingw.
319  * Also, tries to create file in /tmp first, if possible.
320  * *prefix can be a character constant; *filename will be allocated internally.
321  * @return file descriptor of opened file (or negative value corresponding to an
322  * AVERROR code on error)
323  * and opened file name in **filename.
324  * @note On very old libcs it is necessary to set a secure umask before
325  * calling this, av_tempfile() can't call umask itself as it is used in
326  * libraries and could interfere with the calling application.
327  */
328 int avpriv_tempfile(const char *prefix, char **filename, int log_offset, void *log_ctx);
329 
330 int avpriv_set_systematic_pal2(uint32_t pal[256], enum AVPixelFormat pix_fmt);
331 
332 static av_always_inline av_const int avpriv_mirror(int x, int w)
333 {
334  if (!w)
335  return 0;
336 
337  while ((unsigned)x > (unsigned)w) {
338  x = -x;
339  if (x < 0)
340  x += 2 * w;
341  }
342  return x;
343 }
344 
345 void ff_check_pixfmt_descriptors(void);
346 
347 /**
348  * Set a dictionary value to an ISO-8601 compliant timestamp string.
349  *
350  * @param s AVFormatContext
351  * @param key metadata key
352  * @param timestamp unix timestamp in microseconds
353  * @return <0 on error
354  */
355 int avpriv_dict_set_timestamp(AVDictionary **dict, const char *key, int64_t timestamp);
356 
357 #endif /* AVUTIL_INTERNAL_H */
#define av_const
Definition: attributes.h:76
av_warn_unused_result int avpriv_open(const char *filename, int flags,...)
A wrapper for open() setting O_CLOEXEC.
Definition: file_open.c:66
static enum AVPixelFormat pix_fmt
static av_always_inline av_const int64_t ff_rint64_clip(double a, int64_t amin, int64_t amax)
Clip and convert a double value into the long long amin-amax range.
Definition: internal.h:289
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.
static int flags
Definition: log.c:57
high precision timer, useful to profile code
Utility Preprocessor macros.
int avpriv_tempfile(const char *prefix, char **filename, int log_offset, void *log_ctx)
Wrapper to work around the lack of mkstemp() on mingw.
Definition: file_open.c:106
Libavutil version macros.
#define av_printf_format(fmtpos, attrpos)
Definition: attributes.h:155
int avpriv_dict_set_timestamp(AVDictionary **dict, const char *key, int64_t timestamp)
Set a dictionary value to an ISO-8601 compliant timestamp string.
Definition: dict.c:258
static av_always_inline av_const int avpriv_mirror(int x, int w)
Definition: internal.h:332
#define llrint(x)
Definition: libm.h:394
Replacements for frequently missing libm functions.
void avpriv_report_missing_feature(void *avc, const char *msg,...) av_printf_format(2
Log a generic warning message about a missing feature.
#define av_warn_unused_result
Definition: attributes.h:56
void ff_check_pixfmt_descriptors(void)
Definition: pixdesc.c:2387
pixel format definitions
int avpriv_set_systematic_pal2(uint32_t pal[256], enum AVPixelFormat pix_fmt)
Definition: imgutils.c:151
#define av_always_inline
Definition: attributes.h:39
AVPixelFormat
Pixel format.
Definition: pixfmt.h:60