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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 "macros.h"
43 #include "pixfmt.h"
44 #include "version.h"
45 
46 #if ARCH_X86
47 # include "x86/emms.h"
48 #endif
49 
50 #ifndef emms_c
51 # define emms_c() while(0)
52 #endif
53 
54 #ifndef attribute_align_arg
55 #if ARCH_X86_32 && AV_GCC_VERSION_AT_LEAST(4,2)
56 # define attribute_align_arg __attribute__((force_align_arg_pointer))
57 #else
58 # define attribute_align_arg
59 #endif
60 #endif
61 
62 #if defined(_MSC_VER) && CONFIG_SHARED
63 # define av_export __declspec(dllimport)
64 #else
65 # define av_export
66 #endif
67 
68 #if HAVE_PRAGMA_DEPRECATED
69 # if defined(__ICL) || defined (__INTEL_COMPILER)
70 # define FF_DISABLE_DEPRECATION_WARNINGS __pragma(warning(push)) __pragma(warning(disable:1478))
71 # define FF_ENABLE_DEPRECATION_WARNINGS __pragma(warning(pop))
72 # elif defined(_MSC_VER)
73 # define FF_DISABLE_DEPRECATION_WARNINGS __pragma(warning(push)) __pragma(warning(disable:4996))
74 # define FF_ENABLE_DEPRECATION_WARNINGS __pragma(warning(pop))
75 # else
76 # define FF_DISABLE_DEPRECATION_WARNINGS _Pragma("GCC diagnostic ignored \"-Wdeprecated-declarations\"")
77 # define FF_ENABLE_DEPRECATION_WARNINGS _Pragma("GCC diagnostic warning \"-Wdeprecated-declarations\"")
78 # endif
79 #else
80 # define FF_DISABLE_DEPRECATION_WARNINGS
81 # define FF_ENABLE_DEPRECATION_WARNINGS
82 #endif
83 
84 
85 #define FF_MEMORY_POISON 0x2a
86 
87 #define MAKE_ACCESSORS(str, name, type, field) \
88  type av_##name##_get_##field(const str *s) { return s->field; } \
89  void av_##name##_set_##field(str *s, type v) { s->field = v; }
90 
91 // Some broken preprocessors need a second expansion
92 // to be forced to tokenize __VA_ARGS__
93 #define E1(x) x
94 
95 /* Check if the hard coded offset of a struct member still matches reality.
96  * Induce a compilation failure if not.
97  */
98 #define AV_CHECK_OFFSET(s, m, o) struct check_##o { \
99  int x_##o[offsetof(s, m) == o? 1: -1]; \
100  }
101 
102 #define LOCAL_ALIGNED_A(a, t, v, s, o, ...) \
103  uint8_t la_##v[sizeof(t s o) + (a)]; \
104  t (*v) o = (void *)FFALIGN((uintptr_t)la_##v, a)
105 
106 #define LOCAL_ALIGNED_D(a, t, v, s, o, ...) \
107  DECLARE_ALIGNED(a, t, la_##v) s o; \
108  t (*v) o = la_##v
109 
110 #define LOCAL_ALIGNED(a, t, v, ...) E1(LOCAL_ALIGNED_A(a, t, v, __VA_ARGS__,,))
111 
112 #if HAVE_LOCAL_ALIGNED_8
113 # define LOCAL_ALIGNED_8(t, v, ...) E1(LOCAL_ALIGNED_D(8, t, v, __VA_ARGS__,,))
114 #else
115 # define LOCAL_ALIGNED_8(t, v, ...) LOCAL_ALIGNED(8, t, v, __VA_ARGS__)
116 #endif
117 
118 #if HAVE_LOCAL_ALIGNED_16
119 # define LOCAL_ALIGNED_16(t, v, ...) E1(LOCAL_ALIGNED_D(16, t, v, __VA_ARGS__,,))
120 #else
121 # define LOCAL_ALIGNED_16(t, v, ...) LOCAL_ALIGNED(16, t, v, __VA_ARGS__)
122 #endif
123 
124 #if HAVE_LOCAL_ALIGNED_32
125 # define LOCAL_ALIGNED_32(t, v, ...) E1(LOCAL_ALIGNED_D(32, t, v, __VA_ARGS__,,))
126 #else
127 # define LOCAL_ALIGNED_32(t, v, ...) LOCAL_ALIGNED(32, t, v, __VA_ARGS__)
128 #endif
129 
130 #define FF_ALLOC_OR_GOTO(ctx, p, size, label)\
131 {\
132  p = av_malloc(size);\
133  if (!(p) && (size) != 0) {\
134  av_log(ctx, AV_LOG_ERROR, "Cannot allocate memory.\n");\
135  goto label;\
136  }\
137 }
138 
139 #define FF_ALLOCZ_OR_GOTO(ctx, p, size, label)\
140 {\
141  p = av_mallocz(size);\
142  if (!(p) && (size) != 0) {\
143  av_log(ctx, AV_LOG_ERROR, "Cannot allocate memory.\n");\
144  goto label;\
145  }\
146 }
147 
148 #define FF_ALLOC_ARRAY_OR_GOTO(ctx, p, nelem, elsize, label)\
149 {\
150  p = av_malloc_array(nelem, elsize);\
151  if (!p) {\
152  av_log(ctx, AV_LOG_ERROR, "Cannot allocate memory.\n");\
153  goto label;\
154  }\
155 }
156 
157 #define FF_ALLOCZ_ARRAY_OR_GOTO(ctx, p, nelem, elsize, label)\
158 {\
159  p = av_mallocz_array(nelem, elsize);\
160  if (!p) {\
161  av_log(ctx, AV_LOG_ERROR, "Cannot allocate memory.\n");\
162  goto label;\
163  }\
164 }
165 
166 #include "libm.h"
167 
168 /**
169  * Return NULL if CONFIG_SMALL is true, otherwise the argument
170  * without modification. Used to disable the definition of strings
171  * (for example AVCodec long_names).
172  */
173 #if CONFIG_SMALL
174 # define NULL_IF_CONFIG_SMALL(x) NULL
175 #else
176 # define NULL_IF_CONFIG_SMALL(x) x
177 #endif
178 
179 /**
180  * Define a function with only the non-default version specified.
181  *
182  * On systems with ELF shared libraries, all symbols exported from
183  * FFmpeg libraries are tagged with the name and major version of the
184  * library to which they belong. If a function is moved from one
185  * library to another, a wrapper must be retained in the original
186  * location to preserve binary compatibility.
187  *
188  * Functions defined with this macro will never be used to resolve
189  * symbols by the build-time linker.
190  *
191  * @param type return type of function
192  * @param name name of function
193  * @param args argument list of function
194  * @param ver version tag to assign function
195  */
196 #if HAVE_SYMVER_ASM_LABEL
197 # define FF_SYMVER(type, name, args, ver) \
198  type ff_##name args __asm__ (EXTERN_PREFIX #name "@" ver); \
199  type ff_##name args
200 #elif HAVE_SYMVER_GNU_ASM
201 # define FF_SYMVER(type, name, args, ver) \
202  __asm__ (".symver ff_" #name "," EXTERN_PREFIX #name "@" ver); \
203  type ff_##name args; \
204  type ff_##name args
205 #endif
206 
207 /**
208  * Return NULL if a threading library has not been enabled.
209  * Used to disable threading functions in AVCodec definitions
210  * when not needed.
211  */
212 #if HAVE_THREADS
213 # define ONLY_IF_THREADS_ENABLED(x) x
214 #else
215 # define ONLY_IF_THREADS_ENABLED(x) NULL
216 #endif
217 
218 /**
219  * Log a generic warning message about a missing feature.
220  *
221  * @param[in] avc a pointer to an arbitrary struct of which the first
222  * field is a pointer to an AVClass struct
223  * @param[in] msg string containing the name of the missing feature
224  */
225 void avpriv_report_missing_feature(void *avc,
226  const char *msg, ...) av_printf_format(2, 3);
227 
228 /**
229  * Log a generic warning message about a missing feature.
230  * Additionally request that a sample showcasing the feature be uploaded.
231  *
232  * @param[in] avc a pointer to an arbitrary struct of which the first field is
233  * a pointer to an AVClass struct
234  * @param[in] msg string containing the name of the missing feature
235  */
236 void avpriv_request_sample(void *avc,
237  const char *msg, ...) av_printf_format(2, 3);
238 
239 #if HAVE_LIBC_MSVCRT
240 #include <crtversion.h>
241 #if defined(_VC_CRT_MAJOR_VERSION) && _VC_CRT_MAJOR_VERSION < 14
242 #pragma comment(linker, "/include:" EXTERN_PREFIX "avpriv_strtod")
243 #pragma comment(linker, "/include:" EXTERN_PREFIX "avpriv_snprintf")
244 #endif
245 
246 #define avpriv_open ff_open
247 #define avpriv_tempfile ff_tempfile
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 #ifdef DEBUG
256 # define ff_dlog(ctx, ...) av_log(ctx, AV_LOG_DEBUG, __VA_ARGS__)
257 #else
258 # define ff_dlog(ctx, ...) do { if (0) av_log(ctx, AV_LOG_DEBUG, __VA_ARGS__); } while (0)
259 #endif
260 
261 /**
262  * Clip and convert a double value into the long long amin-amax range.
263  * This function is needed because conversion of floating point to integers when
264  * it does not fit in the integer's representation does not necessarily saturate
265  * correctly (usually converted to a cvttsd2si on x86) which saturates numbers
266  * > INT64_MAX to INT64_MIN. The standard marks such conversions as undefined
267  * behavior, allowing this sort of mathematically bogus conversions. This provides
268  * a safe alternative that is slower obviously but assures safety and better
269  * mathematical behavior.
270  * @param a value to clip
271  * @param amin minimum value of the clip range
272  * @param amax maximum value of the clip range
273  * @return clipped value
274  */
275 static av_always_inline av_const int64_t ff_rint64_clip(double a, int64_t amin, int64_t amax)
276 {
277  int64_t res;
278 #if defined(HAVE_AV_CONFIG_H) && defined(ASSERT_LEVEL) && ASSERT_LEVEL >= 2
279  if (amin > amax) abort();
280 #endif
281  // INT64_MAX+1,INT64_MIN are exactly representable as IEEE doubles
282  // do range checks first
283  if (a >= 9223372036854775808.0)
284  return amax;
285  if (a <= -9223372036854775808.0)
286  return amin;
287 
288  // safe to call llrint and clip accordingly
289  res = llrint(a);
290  if (res > amax)
291  return amax;
292  if (res < amin)
293  return amin;
294  return res;
295 }
296 
297 /**
298  * A wrapper for open() setting O_CLOEXEC.
299  */
301 int avpriv_open(const char *filename, int flags, ...);
302 
303 /**
304  * Wrapper to work around the lack of mkstemp() on mingw.
305  * Also, tries to create file in /tmp first, if possible.
306  * *prefix can be a character constant; *filename will be allocated internally.
307  * @return file descriptor of opened file (or negative value corresponding to an
308  * AVERROR code on error)
309  * and opened file name in **filename.
310  * @note On very old libcs it is necessary to set a secure umask before
311  * calling this, av_tempfile() can't call umask itself as it is used in
312  * libraries and could interfere with the calling application.
313  */
314 int avpriv_tempfile(const char *prefix, char **filename, int log_offset, void *log_ctx);
315 
316 int avpriv_set_systematic_pal2(uint32_t pal[256], enum AVPixelFormat pix_fmt);
317 
318 static av_always_inline av_const int avpriv_mirror(int x, int w)
319 {
320  if (!w)
321  return 0;
322 
323  while ((unsigned)x > (unsigned)w) {
324  x = -x;
325  if (x < 0)
326  x += 2 * w;
327  }
328  return x;
329 }
330 
331 void ff_check_pixfmt_descriptors(void);
332 
333 /**
334  * Set a dictionary value to an ISO-8601 compliant timestamp string.
335  *
336  * @param s AVFormatContext
337  * @param key metadata key
338  * @param timestamp unix timestamp in microseconds
339  * @return <0 on error
340  */
341 int avpriv_dict_set_timestamp(AVDictionary **dict, const char *key, int64_t timestamp);
342 
343 extern const uint8_t ff_reverse[256];
344 
345 #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:275
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
Utility Preprocessor macros.
const uint8_t ff_reverse[256]
Definition: reverse.c:23
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:156
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:318
#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.
static int flags
Definition: cpu.c:47
#define av_warn_unused_result
Definition: attributes.h:56
void ff_check_pixfmt_descriptors(void)
Definition: pixdesc.c:2318
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