FFmpeg
utils.c
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1 /*
2  * This file is part of FFmpeg.
3  *
4  * FFmpeg is free software; you can redistribute it and/or
5  * modify it under the terms of the GNU Lesser General Public
6  * License as published by the Free Software Foundation; either
7  * version 2.1 of the License, or (at your option) any later version.
8  *
9  * FFmpeg is distributed in the hope that it will be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12  * Lesser General Public License for more details.
13  *
14  * You should have received a copy of the GNU Lesser General Public
15  * License along with FFmpeg; if not, write to the Free Software
16  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
17  */
18 
19 #include "config.h"
20 #include "avutil.h"
21 #include "avassert.h"
22 #include "samplefmt.h"
23 #include "internal.h"
24 
25 /**
26  * @file
27  * various utility functions
28  */
29 
30 #include "libavutil/ffversion.h"
31 const char av_util_ffversion[] = "FFmpeg version " FFMPEG_VERSION;
32 
33 const char *av_version_info(void)
34 {
35  return FFMPEG_VERSION;
36 }
37 
38 unsigned avutil_version(void)
39 {
40  static int checks_done;
41  if (checks_done)
42  return LIBAVUTIL_VERSION_INT;
43 
48  av_assert0(HAVE_MMX2 == HAVE_MMXEXT);
49 
50  av_assert0(((size_t)-1) > 0); // C guarantees this but if false on a platform we care about revert at least b284e1ffe343d6697fb950d1ee517bafda8a9844
51 
52  if (av_sat_dadd32(1, 2) != 5) {
53  av_log(NULL, AV_LOG_FATAL, "Libavutil has been built with a broken binutils, please upgrade binutils and rebuild\n");
54  abort();
55  }
56 
57  if (llrint(1LL<<60) != 1LL<<60) {
58  av_log(NULL, AV_LOG_ERROR, "Libavutil has been linked to a broken llrint()\n");
59  }
60 
61  checks_done = 1;
62  return LIBAVUTIL_VERSION_INT;
63 }
64 
65 const char *avutil_configuration(void)
66 {
67  return FFMPEG_CONFIGURATION;
68 }
69 
70 const char *avutil_license(void)
71 {
72 #define LICENSE_PREFIX "libavutil license: "
73  return LICENSE_PREFIX FFMPEG_LICENSE + sizeof(LICENSE_PREFIX) - 1;
74 }
75 
76 const char *av_get_media_type_string(enum AVMediaType media_type)
77 {
78  switch (media_type) {
79  case AVMEDIA_TYPE_VIDEO: return "video";
80  case AVMEDIA_TYPE_AUDIO: return "audio";
81  case AVMEDIA_TYPE_DATA: return "data";
82  case AVMEDIA_TYPE_SUBTITLE: return "subtitle";
83  case AVMEDIA_TYPE_ATTACHMENT: return "attachment";
84  default: return NULL;
85  }
86 }
87 
89 {
90  switch (pict_type) {
91  case AV_PICTURE_TYPE_I: return 'I';
92  case AV_PICTURE_TYPE_P: return 'P';
93  case AV_PICTURE_TYPE_B: return 'B';
94  case AV_PICTURE_TYPE_S: return 'S';
95  case AV_PICTURE_TYPE_SI: return 'i';
96  case AV_PICTURE_TYPE_SP: return 'p';
97  case AV_PICTURE_TYPE_BI: return 'b';
98  default: return '?';
99  }
100 }
101 
102 unsigned av_int_list_length_for_size(unsigned elsize,
103  const void *list, uint64_t term)
104 {
105  unsigned i;
106 
107  if (!list)
108  return 0;
109 #define LIST_LENGTH(type) \
110  { type t = term, *l = (type *)list; for (i = 0; l[i] != t; i++); }
111  switch (elsize) {
112  case 1: LIST_LENGTH(uint8_t); break;
113  case 2: LIST_LENGTH(uint16_t); break;
114  case 4: LIST_LENGTH(uint32_t); break;
115  case 8: LIST_LENGTH(uint64_t); break;
116  default: av_assert0(!"valid element size");
117  }
118  return i;
119 }
120 
121 char *av_fourcc_make_string(char *buf, uint32_t fourcc)
122 {
123  int i;
124  char *orig_buf = buf;
125  size_t buf_size = AV_FOURCC_MAX_STRING_SIZE;
126 
127  for (i = 0; i < 4; i++) {
128  const int c = fourcc & 0xff;
129  const int print_chr = (c >= '0' && c <= '9') ||
130  (c >= 'a' && c <= 'z') ||
131  (c >= 'A' && c <= 'Z') ||
132  (c && strchr(". -_", c));
133  const int len = snprintf(buf, buf_size, print_chr ? "%c" : "[%d]", c);
134  if (len < 0)
135  break;
136  buf += len;
137  buf_size = buf_size > len ? buf_size - len : 0;
138  fourcc >>= 8;
139  }
140 
141  return orig_buf;
142 }
143 
145 {
146  return (AVRational){1, AV_TIME_BASE};
147 }
148 
149 void av_assert0_fpu(void) {
150 #if HAVE_MMX_INLINE
151  uint16_t state[14];
152  __asm__ volatile (
153  "fstenv %0 \n\t"
154  : "+m" (state)
155  :
156  : "memory"
157  );
158  av_assert0((state[4] & 3) == 3);
159 #endif
160 }
#define NULL
Definition: coverity.c:32
BI type.
Definition: avutil.h:280
S(GMC)-VOP MPEG-4.
Definition: avutil.h:277
const char * avutil_configuration(void)
Return the libavutil build-time configuration.
Definition: utils.c:65
#define LIBAVUTIL_VERSION_INT
Definition: version.h:85
uint32_t fourcc
Definition: vaapi_decode.c:238
const char av_util_ffversion[]
Definition: utils.c:31
double, planar
Definition: samplefmt.h:70
Convenience header that includes libavutil&#39;s core.
#define LICENSE_PREFIX
Switching Intra.
Definition: avutil.h:278
#define av_assert0(cond)
assert() equivalent, that is always enabled.
Definition: avassert.h:37
uint8_t
Opaque data information usually continuous.
Definition: avutil.h:203
Undefined Behavior In the C some operations are like signed integer dereferencing freed accessing outside allocated Undefined Behavior must not occur in a C it is not safe even if the output of undefined operations is unused The unsafety may seem nit picking but Optimizing compilers have in fact optimized code on the assumption that no undefined Behavior occurs Optimizing code based on wrong assumptions can and has in some cases lead to effects beyond the output of computations The signed integer overflow problem in speed critical code Code which is highly optimized and works with signed integers sometimes has the problem that often the output of the computation does not c
Definition: undefined.txt:32
void av_assert0_fpu(void)
Assert that floating point operations can be executed.
Definition: utils.c:149
char av_get_picture_type_char(enum AVPictureType pict_type)
Return a single letter to describe the given picture type pict_type.
Definition: utils.c:88
#define av_log(a,...)
unsigned avutil_version(void)
Return the LIBAVUTIL_VERSION_INT constant.
Definition: utils.c:38
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:259
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
unsigned av_int_list_length_for_size(unsigned elsize, const void *list, uint64_t term)
Compute the length of an integer list.
Definition: utils.c:102
#define LIBAVUTIL_VERSION_MICRO
Definition: version.h:83
#define AV_FOURCC_MAX_STRING_SIZE
Definition: avutil.h:346
simple assert() macros that are a bit more flexible than ISO C assert().
common internal API header
#define AV_TIME_BASE
Internal time base represented as integer.
Definition: avutil.h:254
const char * av_version_info(void)
Return an informative version string.
Definition: utils.c:33
Opaque data information usually sparse.
Definition: avutil.h:205
char * av_fourcc_make_string(char *buf, uint32_t fourcc)
Fill the provided buffer with a string containing a FourCC (four-character code) representation.
Definition: utils.c:121
const char * avutil_license(void)
Return the libavutil license.
Definition: utils.c:70
#define LIST_LENGTH(type)
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a all references to both lists are replaced with a reference to the intersection And when a single format is eventually chosen for a link amongst the remaining list
void * buf
Definition: avisynth_c.h:766
#define llrint(x)
Definition: libm.h:394
Switching Predicted.
Definition: avutil.h:279
Rational number (pair of numerator and denominator).
Definition: rational.h:58
AVMediaType
Definition: avutil.h:199
AVPictureType
Definition: avutil.h:272
#define snprintf
Definition: snprintf.h:34
AVRational av_get_time_base_q(void)
Return the fractional representation of the internal time base.
Definition: utils.c:144
const char * av_get_media_type_string(enum AVMediaType media_type)
Return a string describing the media_type enum, NULL if media_type is unknown.
Definition: utils.c:76
Bi-dir predicted.
Definition: avutil.h:276
int len
static struct @316 state
#define AV_LOG_FATAL
Something went wrong and recovery is not possible.
Definition: log.h:170
Predicted.
Definition: avutil.h:275