FFmpeg 6.1.1
common.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 and external API header
24 */
25
26#ifndef AVUTIL_COMMON_H
27#define AVUTIL_COMMON_H
28
29#if defined(__cplusplus) && !defined(__STDC_CONSTANT_MACROS) && !defined(UINT64_C)
30#error missing -D__STDC_CONSTANT_MACROS / #define __STDC_CONSTANT_MACROS
31#endif
32
33#include <errno.h>
34#include <inttypes.h>
35#include <limits.h>
36#include <math.h>
37#include <stdint.h>
38#include <stdio.h>
39#include <stdlib.h>
40#include <string.h>
41
42#include "attributes.h"
43#include "error.h"
44#include "macros.h"
45
46//rounded division & shift
47#define RSHIFT(a,b) ((a) > 0 ? ((a) + ((1<<(b))>>1))>>(b) : ((a) + ((1<<(b))>>1)-1)>>(b))
48/* assume b>0 */
49#define ROUNDED_DIV(a,b) (((a)>=0 ? (a) + ((b)>>1) : (a) - ((b)>>1))/(b))
50/* Fast a/(1<<b) rounded toward +inf. Assume a>=0 and b>=0 */
51#define AV_CEIL_RSHIFT(a,b) (!av_builtin_constant_p(b) ? -((-(a)) >> (b)) \
52 : ((a) + (1<<(b)) - 1) >> (b))
53/* Backwards compat. */
54#define FF_CEIL_RSHIFT AV_CEIL_RSHIFT
55
56#define FFUDIV(a,b) (((a)>0 ?(a):(a)-(b)+1) / (b))
57#define FFUMOD(a,b) ((a)-(b)*FFUDIV(a,b))
58
59/**
60 * Absolute value, Note, INT_MIN / INT64_MIN result in undefined behavior as they
61 * are not representable as absolute values of their type. This is the same
62 * as with *abs()
63 * @see FFNABS()
64 */
65#define FFABS(a) ((a) >= 0 ? (a) : (-(a)))
66#define FFSIGN(a) ((a) > 0 ? 1 : -1)
67
68/**
69 * Negative Absolute value.
70 * this works for all integers of all types.
71 * As with many macros, this evaluates its argument twice, it thus must not have
72 * a sideeffect, that is FFNABS(x++) has undefined behavior.
73 */
74#define FFNABS(a) ((a) <= 0 ? (a) : (-(a)))
75
76/**
77 * Unsigned Absolute value.
78 * This takes the absolute value of a signed int and returns it as a unsigned.
79 * This also works with INT_MIN which would otherwise not be representable
80 * As with many macros, this evaluates its argument twice.
81 */
82#define FFABSU(a) ((a) <= 0 ? -(unsigned)(a) : (unsigned)(a))
83#define FFABS64U(a) ((a) <= 0 ? -(uint64_t)(a) : (uint64_t)(a))
84
85/* misc math functions */
86
87#ifdef HAVE_AV_CONFIG_H
88# include "config.h"
89# include "intmath.h"
90#endif
91
92#ifndef av_ceil_log2
93# define av_ceil_log2 av_ceil_log2_c
94#endif
95#ifndef av_clip
96# define av_clip av_clip_c
97#endif
98#ifndef av_clip64
99# define av_clip64 av_clip64_c
100#endif
101#ifndef av_clip_uint8
102# define av_clip_uint8 av_clip_uint8_c
103#endif
104#ifndef av_clip_int8
105# define av_clip_int8 av_clip_int8_c
106#endif
107#ifndef av_clip_uint16
108# define av_clip_uint16 av_clip_uint16_c
109#endif
110#ifndef av_clip_int16
111# define av_clip_int16 av_clip_int16_c
112#endif
113#ifndef av_clipl_int32
114# define av_clipl_int32 av_clipl_int32_c
115#endif
116#ifndef av_clip_intp2
117# define av_clip_intp2 av_clip_intp2_c
118#endif
119#ifndef av_clip_uintp2
120# define av_clip_uintp2 av_clip_uintp2_c
121#endif
122#ifndef av_mod_uintp2
123# define av_mod_uintp2 av_mod_uintp2_c
124#endif
125#ifndef av_sat_add32
126# define av_sat_add32 av_sat_add32_c
127#endif
128#ifndef av_sat_dadd32
129# define av_sat_dadd32 av_sat_dadd32_c
130#endif
131#ifndef av_sat_sub32
132# define av_sat_sub32 av_sat_sub32_c
133#endif
134#ifndef av_sat_dsub32
135# define av_sat_dsub32 av_sat_dsub32_c
136#endif
137#ifndef av_sat_add64
138# define av_sat_add64 av_sat_add64_c
139#endif
140#ifndef av_sat_sub64
141# define av_sat_sub64 av_sat_sub64_c
142#endif
143#ifndef av_clipf
144# define av_clipf av_clipf_c
145#endif
146#ifndef av_clipd
147# define av_clipd av_clipd_c
148#endif
149#ifndef av_popcount
150# define av_popcount av_popcount_c
151#endif
152#ifndef av_popcount64
153# define av_popcount64 av_popcount64_c
154#endif
155#ifndef av_parity
156# define av_parity av_parity_c
157#endif
158
159#ifndef av_log2
160av_const int av_log2(unsigned v);
161#endif
162
163#ifndef av_log2_16bit
164av_const int av_log2_16bit(unsigned v);
165#endif
166
167/**
168 * Clip a signed integer value into the amin-amax range.
169 * @param a value to clip
170 * @param amin minimum value of the clip range
171 * @param amax maximum value of the clip range
172 * @return clipped value
173 */
174static av_always_inline av_const int av_clip_c(int a, int amin, int amax)
175{
176#if defined(HAVE_AV_CONFIG_H) && defined(ASSERT_LEVEL) && ASSERT_LEVEL >= 2
177 if (amin > amax) abort();
178#endif
179 if (a < amin) return amin;
180 else if (a > amax) return amax;
181 else return a;
182}
183
184/**
185 * Clip a signed 64bit integer value into the amin-amax range.
186 * @param a value to clip
187 * @param amin minimum value of the clip range
188 * @param amax maximum value of the clip range
189 * @return clipped value
190 */
191static av_always_inline av_const int64_t av_clip64_c(int64_t a, int64_t amin, int64_t amax)
192{
193#if defined(HAVE_AV_CONFIG_H) && defined(ASSERT_LEVEL) && ASSERT_LEVEL >= 2
194 if (amin > amax) abort();
195#endif
196 if (a < amin) return amin;
197 else if (a > amax) return amax;
198 else return a;
199}
200
201/**
202 * Clip a signed integer value into the 0-255 range.
203 * @param a value to clip
204 * @return clipped value
205 */
207{
208 if (a&(~0xFF)) return (~a)>>31;
209 else return a;
210}
211
212/**
213 * Clip a signed integer value into the -128,127 range.
214 * @param a value to clip
215 * @return clipped value
216 */
218{
219 if ((a+0x80U) & ~0xFF) return (a>>31) ^ 0x7F;
220 else return a;
221}
222
223/**
224 * Clip a signed integer value into the 0-65535 range.
225 * @param a value to clip
226 * @return clipped value
227 */
229{
230 if (a&(~0xFFFF)) return (~a)>>31;
231 else return a;
232}
233
234/**
235 * Clip a signed integer value into the -32768,32767 range.
236 * @param a value to clip
237 * @return clipped value
238 */
240{
241 if ((a+0x8000U) & ~0xFFFF) return (a>>31) ^ 0x7FFF;
242 else return a;
243}
244
245/**
246 * Clip a signed 64-bit integer value into the -2147483648,2147483647 range.
247 * @param a value to clip
248 * @return clipped value
249 */
251{
252 if ((a+0x80000000u) & ~UINT64_C(0xFFFFFFFF)) return (int32_t)((a>>63) ^ 0x7FFFFFFF);
253 else return (int32_t)a;
254}
255
256/**
257 * Clip a signed integer into the -(2^p),(2^p-1) range.
258 * @param a value to clip
259 * @param p bit position to clip at
260 * @return clipped value
261 */
263{
264 if (((unsigned)a + (1 << p)) & ~((2 << p) - 1))
265 return (a >> 31) ^ ((1 << p) - 1);
266 else
267 return a;
268}
269
270/**
271 * Clip a signed integer to an unsigned power of two range.
272 * @param a value to clip
273 * @param p bit position to clip at
274 * @return clipped value
275 */
276static av_always_inline av_const unsigned av_clip_uintp2_c(int a, int p)
277{
278 if (a & ~((1<<p) - 1)) return (~a) >> 31 & ((1<<p) - 1);
279 else return a;
280}
281
282/**
283 * Clear high bits from an unsigned integer starting with specific bit position
284 * @param a value to clip
285 * @param p bit position to clip at
286 * @return clipped value
287 */
288static av_always_inline av_const unsigned av_mod_uintp2_c(unsigned a, unsigned p)
289{
290 return a & ((1U << p) - 1);
291}
292
293/**
294 * Add two signed 32-bit values with saturation.
295 *
296 * @param a one value
297 * @param b another value
298 * @return sum with signed saturation
299 */
300static av_always_inline int av_sat_add32_c(int a, int b)
301{
302 return av_clipl_int32((int64_t)a + b);
303}
304
305/**
306 * Add a doubled value to another value with saturation at both stages.
307 *
308 * @param a first value
309 * @param b value doubled and added to a
310 * @return sum sat(a + sat(2*b)) with signed saturation
311 */
312static av_always_inline int av_sat_dadd32_c(int a, int b)
313{
314 return av_sat_add32(a, av_sat_add32(b, b));
315}
316
317/**
318 * Subtract two signed 32-bit values with saturation.
319 *
320 * @param a one value
321 * @param b another value
322 * @return difference with signed saturation
323 */
324static av_always_inline int av_sat_sub32_c(int a, int b)
325{
326 return av_clipl_int32((int64_t)a - b);
327}
328
329/**
330 * Subtract a doubled value from another value with saturation at both stages.
331 *
332 * @param a first value
333 * @param b value doubled and subtracted from a
334 * @return difference sat(a - sat(2*b)) with signed saturation
335 */
336static av_always_inline int av_sat_dsub32_c(int a, int b)
337{
338 return av_sat_sub32(a, av_sat_add32(b, b));
339}
340
341/**
342 * Add two signed 64-bit values with saturation.
343 *
344 * @param a one value
345 * @param b another value
346 * @return sum with signed saturation
347 */
348static av_always_inline int64_t av_sat_add64_c(int64_t a, int64_t b) {
349#if (!defined(__INTEL_COMPILER) && AV_GCC_VERSION_AT_LEAST(5,1)) || AV_HAS_BUILTIN(__builtin_add_overflow)
350 int64_t tmp;
351 return !__builtin_add_overflow(a, b, &tmp) ? tmp : (tmp < 0 ? INT64_MAX : INT64_MIN);
352#else
353 int64_t s = a+(uint64_t)b;
354 if ((int64_t)(a^b | ~s^b) >= 0)
355 return INT64_MAX ^ (b >> 63);
356 return s;
357#endif
358}
359
360/**
361 * Subtract two signed 64-bit values with saturation.
362 *
363 * @param a one value
364 * @param b another value
365 * @return difference with signed saturation
366 */
367static av_always_inline int64_t av_sat_sub64_c(int64_t a, int64_t b) {
368#if (!defined(__INTEL_COMPILER) && AV_GCC_VERSION_AT_LEAST(5,1)) || AV_HAS_BUILTIN(__builtin_sub_overflow)
369 int64_t tmp;
370 return !__builtin_sub_overflow(a, b, &tmp) ? tmp : (tmp < 0 ? INT64_MAX : INT64_MIN);
371#else
372 if (b <= 0 && a >= INT64_MAX + b)
373 return INT64_MAX;
374 if (b >= 0 && a <= INT64_MIN + b)
375 return INT64_MIN;
376 return a - b;
377#endif
378}
379
380/**
381 * Clip a float value into the amin-amax range.
382 * If a is nan or -inf amin will be returned.
383 * If a is +inf amax will be returned.
384 * @param a value to clip
385 * @param amin minimum value of the clip range
386 * @param amax maximum value of the clip range
387 * @return clipped value
388 */
389static av_always_inline av_const float av_clipf_c(float a, float amin, float amax)
390{
391#if defined(HAVE_AV_CONFIG_H) && defined(ASSERT_LEVEL) && ASSERT_LEVEL >= 2
392 if (amin > amax) abort();
393#endif
394 return FFMIN(FFMAX(a, amin), amax);
395}
396
397/**
398 * Clip a double value into the amin-amax range.
399 * If a is nan or -inf amin will be returned.
400 * If a is +inf amax will be returned.
401 * @param a value to clip
402 * @param amin minimum value of the clip range
403 * @param amax maximum value of the clip range
404 * @return clipped value
405 */
406static av_always_inline av_const double av_clipd_c(double a, double amin, double amax)
407{
408#if defined(HAVE_AV_CONFIG_H) && defined(ASSERT_LEVEL) && ASSERT_LEVEL >= 2
409 if (amin > amax) abort();
410#endif
411 return FFMIN(FFMAX(a, amin), amax);
412}
413
414/** Compute ceil(log2(x)).
415 * @param x value used to compute ceil(log2(x))
416 * @return computed ceiling of log2(x)
417 */
419{
420 return av_log2((x - 1U) << 1);
421}
422
423/**
424 * Count number of bits set to one in x
425 * @param x value to count bits of
426 * @return the number of bits set to one in x
427 */
429{
430 x -= (x >> 1) & 0x55555555;
431 x = (x & 0x33333333) + ((x >> 2) & 0x33333333);
432 x = (x + (x >> 4)) & 0x0F0F0F0F;
433 x += x >> 8;
434 return (x + (x >> 16)) & 0x3F;
435}
436
437/**
438 * Count number of bits set to one in x
439 * @param x value to count bits of
440 * @return the number of bits set to one in x
441 */
443{
444 return av_popcount((uint32_t)x) + av_popcount((uint32_t)(x >> 32));
445}
446
448{
449 return av_popcount(v) & 1;
450}
451
452/**
453 * Convert a UTF-8 character (up to 4 bytes) to its 32-bit UCS-4 encoded form.
454 *
455 * @param val Output value, must be an lvalue of type uint32_t.
456 * @param GET_BYTE Expression reading one byte from the input.
457 * Evaluated up to 7 times (4 for the currently
458 * assigned Unicode range). With a memory buffer
459 * input, this could be *ptr++, or if you want to make sure
460 * that *ptr stops at the end of a NULL terminated string then
461 * *ptr ? *ptr++ : 0
462 * @param ERROR Expression to be evaluated on invalid input,
463 * typically a goto statement.
464 *
465 * @warning ERROR should not contain a loop control statement which
466 * could interact with the internal while loop, and should force an
467 * exit from the macro code (e.g. through a goto or a return) in order
468 * to prevent undefined results.
469 */
470#define GET_UTF8(val, GET_BYTE, ERROR)\
471 val= (GET_BYTE);\
472 {\
473 uint32_t top = (val & 128) >> 1;\
474 if ((val & 0xc0) == 0x80 || val >= 0xFE)\
475 {ERROR}\
476 while (val & top) {\
477 unsigned int tmp = (GET_BYTE) - 128;\
478 if(tmp>>6)\
479 {ERROR}\
480 val= (val<<6) + tmp;\
481 top <<= 5;\
482 }\
483 val &= (top << 1) - 1;\
484 }
485
486/**
487 * Convert a UTF-16 character (2 or 4 bytes) to its 32-bit UCS-4 encoded form.
488 *
489 * @param val Output value, must be an lvalue of type uint32_t.
490 * @param GET_16BIT Expression returning two bytes of UTF-16 data converted
491 * to native byte order. Evaluated one or two times.
492 * @param ERROR Expression to be evaluated on invalid input,
493 * typically a goto statement.
494 */
495#define GET_UTF16(val, GET_16BIT, ERROR)\
496 val = (GET_16BIT);\
497 {\
498 unsigned int hi = val - 0xD800;\
499 if (hi < 0x800) {\
500 val = (GET_16BIT) - 0xDC00;\
501 if (val > 0x3FFU || hi > 0x3FFU)\
502 {ERROR}\
503 val += (hi<<10) + 0x10000;\
504 }\
505 }\
506
507/**
508 * @def PUT_UTF8(val, tmp, PUT_BYTE)
509 * Convert a 32-bit Unicode character to its UTF-8 encoded form (up to 4 bytes long).
510 * @param val is an input-only argument and should be of type uint32_t. It holds
511 * a UCS-4 encoded Unicode character that is to be converted to UTF-8. If
512 * val is given as a function it is executed only once.
513 * @param tmp is a temporary variable and should be of type uint8_t. It
514 * represents an intermediate value during conversion that is to be
515 * output by PUT_BYTE.
516 * @param PUT_BYTE writes the converted UTF-8 bytes to any proper destination.
517 * It could be a function or a statement, and uses tmp as the input byte.
518 * For example, PUT_BYTE could be "*output++ = tmp;" PUT_BYTE will be
519 * executed up to 4 times for values in the valid UTF-8 range and up to
520 * 7 times in the general case, depending on the length of the converted
521 * Unicode character.
522 */
523#define PUT_UTF8(val, tmp, PUT_BYTE)\
524 {\
525 int bytes, shift;\
526 uint32_t in = val;\
527 if (in < 0x80) {\
528 tmp = in;\
529 PUT_BYTE\
530 } else {\
531 bytes = (av_log2(in) + 4) / 5;\
532 shift = (bytes - 1) * 6;\
533 tmp = (256 - (256 >> bytes)) | (in >> shift);\
534 PUT_BYTE\
535 while (shift >= 6) {\
536 shift -= 6;\
537 tmp = 0x80 | ((in >> shift) & 0x3f);\
538 PUT_BYTE\
539 }\
540 }\
541 }
542
543/**
544 * @def PUT_UTF16(val, tmp, PUT_16BIT)
545 * Convert a 32-bit Unicode character to its UTF-16 encoded form (2 or 4 bytes).
546 * @param val is an input-only argument and should be of type uint32_t. It holds
547 * a UCS-4 encoded Unicode character that is to be converted to UTF-16. If
548 * val is given as a function it is executed only once.
549 * @param tmp is a temporary variable and should be of type uint16_t. It
550 * represents an intermediate value during conversion that is to be
551 * output by PUT_16BIT.
552 * @param PUT_16BIT writes the converted UTF-16 data to any proper destination
553 * in desired endianness. It could be a function or a statement, and uses tmp
554 * as the input byte. For example, PUT_BYTE could be "*output++ = tmp;"
555 * PUT_BYTE will be executed 1 or 2 times depending on input character.
556 */
557#define PUT_UTF16(val, tmp, PUT_16BIT)\
558 {\
559 uint32_t in = val;\
560 if (in < 0x10000) {\
561 tmp = in;\
562 PUT_16BIT\
563 } else {\
564 tmp = 0xD800 | ((in - 0x10000) >> 10);\
565 PUT_16BIT\
566 tmp = 0xDC00 | ((in - 0x10000) & 0x3FF);\
567 PUT_16BIT\
568 }\
569 }\
570
571
572
573#include "mem.h"
574
575#ifdef HAVE_AV_CONFIG_H
576# include "internal.h"
577#endif /* HAVE_AV_CONFIG_H */
578
579#endif /* AVUTIL_COMMON_H */
Macro definitions for various function/variable attributes.
#define av_always_inline
Definition: attributes.h:45
#define av_const
Definition: attributes.h:82
static av_always_inline int64_t av_sat_sub64_c(int64_t a, int64_t b)
Subtract two signed 64-bit values with saturation.
Definition: common.h:367
static av_always_inline av_const int av_popcount64_c(uint64_t x)
Count number of bits set to one in x.
Definition: common.h:442
av_const int av_log2(unsigned v)
static av_always_inline int av_sat_add32_c(int a, int b)
Add two signed 32-bit values with saturation.
Definition: common.h:300
static av_always_inline av_const int8_t av_clip_int8_c(int a)
Clip a signed integer value into the -128,127 range.
Definition: common.h:217
static av_always_inline av_const unsigned av_mod_uintp2_c(unsigned a, unsigned p)
Clear high bits from an unsigned integer starting with specific bit position.
Definition: common.h:288
static av_always_inline av_const int av_clip_c(int a, int amin, int amax)
Clip a signed integer value into the amin-amax range.
Definition: common.h:174
#define av_popcount
Definition: common.h:150
static av_always_inline int av_sat_dsub32_c(int a, int b)
Subtract a doubled value from another value with saturation at both stages.
Definition: common.h:336
static av_always_inline av_const uint16_t av_clip_uint16_c(int a)
Clip a signed integer value into the 0-65535 range.
Definition: common.h:228
static av_always_inline av_const int av_popcount_c(uint32_t x)
Count number of bits set to one in x.
Definition: common.h:428
static av_always_inline int av_sat_sub32_c(int a, int b)
Subtract two signed 32-bit values with saturation.
Definition: common.h:324
static av_always_inline av_const float av_clipf_c(float a, float amin, float amax)
Clip a float value into the amin-amax range.
Definition: common.h:389
static av_always_inline int64_t av_sat_add64_c(int64_t a, int64_t b)
Add two signed 64-bit values with saturation.
Definition: common.h:348
#define av_clipl_int32
Definition: common.h:114
static av_always_inline av_const unsigned av_clip_uintp2_c(int a, int p)
Clip a signed integer to an unsigned power of two range.
Definition: common.h:276
#define av_sat_add32
Definition: common.h:126
av_const int av_log2_16bit(unsigned v)
static av_always_inline av_const uint8_t av_clip_uint8_c(int a)
Clip a signed integer value into the 0-255 range.
Definition: common.h:206
static av_always_inline av_const double av_clipd_c(double a, double amin, double amax)
Clip a double value into the amin-amax range.
Definition: common.h:406
static av_always_inline av_const int64_t av_clip64_c(int64_t a, int64_t amin, int64_t amax)
Clip a signed 64bit integer value into the amin-amax range.
Definition: common.h:191
static av_always_inline av_const int16_t av_clip_int16_c(int a)
Clip a signed integer value into the -32768,32767 range.
Definition: common.h:239
static av_always_inline av_const int av_clip_intp2_c(int a, int p)
Clip a signed integer into the -(2^p),(2^p-1) range.
Definition: common.h:262
static av_always_inline av_const int av_ceil_log2_c(int x)
Compute ceil(log2(x)).
Definition: common.h:418
static av_always_inline av_const int32_t av_clipl_int32_c(int64_t a)
Clip a signed 64-bit integer value into the -2147483648,2147483647 range.
Definition: common.h:250
static av_always_inline av_const int av_parity_c(uint32_t v)
Definition: common.h:447
static av_always_inline int av_sat_dadd32_c(int a, int b)
Add a doubled value to another value with saturation at both stages.
Definition: common.h:312
#define av_sat_sub32
Definition: common.h:132
error code definitions
Utility Preprocessor macros.
#define FFMIN(a, b)
Definition: macros.h:49
#define FFMAX(a, b)
Definition: macros.h:47
Memory handling functions.