common.h (17563B)
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 #include "version.h" 46 47 #ifdef HAVE_AV_CONFIG_H 48 # include "config.h" 49 # include "intmath.h" 50 # include "internal.h" 51 #else 52 # include "mem.h" 53 #endif /* HAVE_AV_CONFIG_H */ 54 55 //rounded division & shift 56 #define RSHIFT(a,b) ((a) > 0 ? ((a) + ((1<<(b))>>1))>>(b) : ((a) + ((1<<(b))>>1)-1)>>(b)) 57 /* assume b>0 */ 58 #define ROUNDED_DIV(a,b) (((a)>=0 ? (a) + ((b)>>1) : (a) - ((b)>>1))/(b)) 59 /* Fast a/(1<<b) rounded toward +inf. Assume a>=0 and b>=0 */ 60 #define AV_CEIL_RSHIFT(a,b) (!av_builtin_constant_p(b) ? -((-(a)) >> (b)) \ 61 : ((a) + (1<<(b)) - 1) >> (b)) 62 /* Backwards compat. */ 63 #define FF_CEIL_RSHIFT AV_CEIL_RSHIFT 64 65 #define FFUDIV(a,b) (((a)>0 ?(a):(a)-(b)+1) / (b)) 66 #define FFUMOD(a,b) ((a)-(b)*FFUDIV(a,b)) 67 68 /** 69 * Absolute value, Note, INT_MIN / INT64_MIN result in undefined behavior as they 70 * are not representable as absolute values of their type. This is the same 71 * as with *abs() 72 * @see FFNABS() 73 */ 74 #define FFABS(a) ((a) >= 0 ? (a) : (-(a))) 75 #define FFSIGN(a) ((a) > 0 ? 1 : -1) 76 77 /** 78 * Negative Absolute value. 79 * this works for all integers of all types. 80 * As with many macros, this evaluates its argument twice, it thus must not have 81 * a sideeffect, that is FFNABS(x++) has undefined behavior. 82 */ 83 #define FFNABS(a) ((a) <= 0 ? (a) : (-(a))) 84 85 /** 86 * Unsigned Absolute value. 87 * This takes the absolute value of a signed int and returns it as a unsigned. 88 * This also works with INT_MIN which would otherwise not be representable 89 * As with many macros, this evaluates its argument twice. 90 */ 91 #define FFABSU(a) ((a) <= 0 ? -(unsigned)(a) : (unsigned)(a)) 92 #define FFABS64U(a) ((a) <= 0 ? -(uint64_t)(a) : (uint64_t)(a)) 93 94 /* misc math functions */ 95 96 #ifndef av_ceil_log2 97 # define av_ceil_log2 av_ceil_log2_c 98 #endif 99 #ifndef av_clip 100 # define av_clip av_clip_c 101 #endif 102 #ifndef av_clip64 103 # define av_clip64 av_clip64_c 104 #endif 105 #ifndef av_clip_uint8 106 # define av_clip_uint8 av_clip_uint8_c 107 #endif 108 #ifndef av_clip_int8 109 # define av_clip_int8 av_clip_int8_c 110 #endif 111 #ifndef av_clip_uint16 112 # define av_clip_uint16 av_clip_uint16_c 113 #endif 114 #ifndef av_clip_int16 115 # define av_clip_int16 av_clip_int16_c 116 #endif 117 #ifndef av_clipl_int32 118 # define av_clipl_int32 av_clipl_int32_c 119 #endif 120 #ifndef av_clip_intp2 121 # define av_clip_intp2 av_clip_intp2_c 122 #endif 123 #ifndef av_clip_uintp2 124 # define av_clip_uintp2 av_clip_uintp2_c 125 #endif 126 #ifndef av_sat_add32 127 # define av_sat_add32 av_sat_add32_c 128 #endif 129 #ifndef av_sat_dadd32 130 # define av_sat_dadd32 av_sat_dadd32_c 131 #endif 132 #ifndef av_sat_sub32 133 # define av_sat_sub32 av_sat_sub32_c 134 #endif 135 #ifndef av_sat_dsub32 136 # define av_sat_dsub32 av_sat_dsub32_c 137 #endif 138 #ifndef av_sat_add64 139 # define av_sat_add64 av_sat_add64_c 140 #endif 141 #ifndef av_sat_sub64 142 # define av_sat_sub64 av_sat_sub64_c 143 #endif 144 #ifndef av_clipf 145 # define av_clipf av_clipf_c 146 #endif 147 #ifndef av_clipd 148 # define av_clipd av_clipd_c 149 #endif 150 #ifndef av_zero_extend 151 # define av_zero_extend av_zero_extend_c 152 #endif 153 #ifndef av_popcount 154 # define av_popcount av_popcount_c 155 #endif 156 #ifndef av_popcount64 157 # define av_popcount64 av_popcount64_c 158 #endif 159 #ifndef av_parity 160 # define av_parity av_parity_c 161 #endif 162 163 #ifndef av_log2 164 av_const int av_log2(unsigned v); 165 #endif 166 167 #ifndef av_log2_16bit 168 av_const int av_log2_16bit(unsigned v); 169 #endif 170 171 /** 172 * Clip a signed integer value into the amin-amax range. 173 * @param a value to clip 174 * @param amin minimum value of the clip range 175 * @param amax maximum value of the clip range 176 * @return clipped value 177 */ 178 static av_always_inline av_const int av_clip_c(int a, int amin, int amax) 179 { 180 #if defined(HAVE_AV_CONFIG_H) && defined(ASSERT_LEVEL) && ASSERT_LEVEL >= 2 181 if (amin > amax) abort(); 182 #endif 183 if (a < amin) return amin; 184 else if (a > amax) return amax; 185 else return a; 186 } 187 188 /** 189 * Clip a signed 64bit integer value into the amin-amax range. 190 * @param a value to clip 191 * @param amin minimum value of the clip range 192 * @param amax maximum value of the clip range 193 * @return clipped value 194 */ 195 static av_always_inline av_const int64_t av_clip64_c(int64_t a, int64_t amin, int64_t amax) 196 { 197 #if defined(HAVE_AV_CONFIG_H) && defined(ASSERT_LEVEL) && ASSERT_LEVEL >= 2 198 if (amin > amax) abort(); 199 #endif 200 if (a < amin) return amin; 201 else if (a > amax) return amax; 202 else return a; 203 } 204 205 /** 206 * Clip a signed integer value into the 0-255 range. 207 * @param a value to clip 208 * @return clipped value 209 */ 210 static av_always_inline av_const uint8_t av_clip_uint8_c(int a) 211 { 212 if (a&(~0xFF)) return (~a)>>31; 213 else return a; 214 } 215 216 /** 217 * Clip a signed integer value into the -128,127 range. 218 * @param a value to clip 219 * @return clipped value 220 */ 221 static av_always_inline av_const int8_t av_clip_int8_c(int a) 222 { 223 if ((a+0x80U) & ~0xFF) return (a>>31) ^ 0x7F; 224 else return a; 225 } 226 227 /** 228 * Clip a signed integer value into the 0-65535 range. 229 * @param a value to clip 230 * @return clipped value 231 */ 232 static av_always_inline av_const uint16_t av_clip_uint16_c(int a) 233 { 234 if (a&(~0xFFFF)) return (~a)>>31; 235 else return a; 236 } 237 238 /** 239 * Clip a signed integer value into the -32768,32767 range. 240 * @param a value to clip 241 * @return clipped value 242 */ 243 static av_always_inline av_const int16_t av_clip_int16_c(int a) 244 { 245 if ((a+0x8000U) & ~0xFFFF) return (a>>31) ^ 0x7FFF; 246 else return a; 247 } 248 249 /** 250 * Clip a signed 64-bit integer value into the -2147483648,2147483647 range. 251 * @param a value to clip 252 * @return clipped value 253 */ 254 static av_always_inline av_const int32_t av_clipl_int32_c(int64_t a) 255 { 256 if ((a+UINT64_C(0x80000000)) & ~UINT64_C(0xFFFFFFFF)) return (int32_t)((a>>63) ^ 0x7FFFFFFF); 257 else return (int32_t)a; 258 } 259 260 /** 261 * Clip a signed integer into the -(2^p),(2^p-1) range. 262 * @param a value to clip 263 * @param p bit position to clip at 264 * @return clipped value 265 */ 266 static av_always_inline av_const int av_clip_intp2_c(int a, int p) 267 { 268 if (((unsigned)a + (1U << p)) & ~((2U << p) - 1)) 269 return (a >> 31) ^ ((1 << p) - 1); 270 else 271 return a; 272 } 273 274 /** 275 * Clip a signed integer to an unsigned power of two range. 276 * @param a value to clip 277 * @param p bit position to clip at 278 * @return clipped value 279 */ 280 static av_always_inline av_const unsigned av_clip_uintp2_c(int a, int p) 281 { 282 if (a & ~((1U<<p) - 1)) return (~a) >> 31 & ((1U<<p) - 1); 283 else return a; 284 } 285 286 /** 287 * Clear high bits from an unsigned integer starting with specific bit position 288 * @param a value to clip 289 * @param p bit position to clip at. Must be between 0 and 31. 290 * @return clipped value 291 */ 292 static av_always_inline av_const unsigned av_zero_extend_c(unsigned a, unsigned p) 293 { 294 #if defined(HAVE_AV_CONFIG_H) && defined(ASSERT_LEVEL) && ASSERT_LEVEL >= 2 295 if (p > 31) abort(); 296 #endif 297 return a & ((1U << p) - 1); 298 } 299 300 #if FF_API_MOD_UINTP2 301 #ifndef av_mod_uintp2 302 # define av_mod_uintp2 av_mod_uintp2_c 303 #endif 304 attribute_deprecated 305 static av_always_inline av_const unsigned av_mod_uintp2_c(unsigned a, unsigned p) 306 { 307 return av_zero_extend_c(a, p); 308 } 309 #endif 310 311 /** 312 * Add two signed 32-bit values with saturation. 313 * 314 * @param a one value 315 * @param b another value 316 * @return sum with signed saturation 317 */ 318 static av_always_inline int av_sat_add32_c(int a, int b) 319 { 320 return av_clipl_int32((int64_t)a + b); 321 } 322 323 /** 324 * Add a doubled value to another value with saturation at both stages. 325 * 326 * @param a first value 327 * @param b value doubled and added to a 328 * @return sum sat(a + sat(2*b)) with signed saturation 329 */ 330 static av_always_inline int av_sat_dadd32_c(int a, int b) 331 { 332 return av_sat_add32(a, av_sat_add32(b, b)); 333 } 334 335 /** 336 * Subtract two signed 32-bit values with saturation. 337 * 338 * @param a one value 339 * @param b another value 340 * @return difference with signed saturation 341 */ 342 static av_always_inline int av_sat_sub32_c(int a, int b) 343 { 344 return av_clipl_int32((int64_t)a - b); 345 } 346 347 /** 348 * Subtract a doubled value from another value with saturation at both stages. 349 * 350 * @param a first value 351 * @param b value doubled and subtracted from a 352 * @return difference sat(a - sat(2*b)) with signed saturation 353 */ 354 static av_always_inline int av_sat_dsub32_c(int a, int b) 355 { 356 return av_sat_sub32(a, av_sat_add32(b, b)); 357 } 358 359 /** 360 * Add two signed 64-bit values with saturation. 361 * 362 * @param a one value 363 * @param b another value 364 * @return sum with signed saturation 365 */ 366 static av_always_inline int64_t av_sat_add64_c(int64_t a, int64_t b) { 367 #if (!defined(__INTEL_COMPILER) && AV_GCC_VERSION_AT_LEAST(5,1)) || AV_HAS_BUILTIN(__builtin_add_overflow) 368 int64_t tmp; 369 return !__builtin_add_overflow(a, b, &tmp) ? tmp : (tmp < 0 ? INT64_MAX : INT64_MIN); 370 #else 371 int64_t s = a+(uint64_t)b; 372 if ((int64_t)(a^b | ~s^b) >= 0) 373 return INT64_MAX ^ (b >> 63); 374 return s; 375 #endif 376 } 377 378 /** 379 * Subtract two signed 64-bit values with saturation. 380 * 381 * @param a one value 382 * @param b another value 383 * @return difference with signed saturation 384 */ 385 static av_always_inline int64_t av_sat_sub64_c(int64_t a, int64_t b) { 386 #if (!defined(__INTEL_COMPILER) && AV_GCC_VERSION_AT_LEAST(5,1)) || AV_HAS_BUILTIN(__builtin_sub_overflow) 387 int64_t tmp; 388 return !__builtin_sub_overflow(a, b, &tmp) ? tmp : (tmp < 0 ? INT64_MAX : INT64_MIN); 389 #else 390 if (b <= 0 && a >= INT64_MAX + b) 391 return INT64_MAX; 392 if (b >= 0 && a <= INT64_MIN + b) 393 return INT64_MIN; 394 return a - b; 395 #endif 396 } 397 398 /** 399 * Clip a float value into the amin-amax range. 400 * If a is nan or -inf amin will be returned. 401 * If a is +inf amax will be returned. 402 * @param a value to clip 403 * @param amin minimum value of the clip range 404 * @param amax maximum value of the clip range 405 * @return clipped value 406 */ 407 static av_always_inline av_const float av_clipf_c(float a, float amin, float amax) 408 { 409 #if defined(HAVE_AV_CONFIG_H) && defined(ASSERT_LEVEL) && ASSERT_LEVEL >= 2 410 if (amin > amax) abort(); 411 #endif 412 return FFMIN(FFMAX(a, amin), amax); 413 } 414 415 /** 416 * Clip a double value into the amin-amax range. 417 * If a is nan or -inf amin will be returned. 418 * If a is +inf amax will be returned. 419 * @param a value to clip 420 * @param amin minimum value of the clip range 421 * @param amax maximum value of the clip range 422 * @return clipped value 423 */ 424 static av_always_inline av_const double av_clipd_c(double a, double amin, double amax) 425 { 426 #if defined(HAVE_AV_CONFIG_H) && defined(ASSERT_LEVEL) && ASSERT_LEVEL >= 2 427 if (amin > amax) abort(); 428 #endif 429 return FFMIN(FFMAX(a, amin), amax); 430 } 431 432 /** Compute ceil(log2(x)). 433 * @param x value used to compute ceil(log2(x)) 434 * @return computed ceiling of log2(x) 435 */ 436 static av_always_inline av_const int av_ceil_log2_c(int x) 437 { 438 return av_log2((x - 1U) << 1); 439 } 440 441 /** 442 * Count number of bits set to one in x 443 * @param x value to count bits of 444 * @return the number of bits set to one in x 445 */ 446 static av_always_inline av_const int av_popcount_c(uint32_t x) 447 { 448 x -= (x >> 1) & 0x55555555; 449 x = (x & 0x33333333) + ((x >> 2) & 0x33333333); 450 x = (x + (x >> 4)) & 0x0F0F0F0F; 451 x += x >> 8; 452 return (x + (x >> 16)) & 0x3F; 453 } 454 455 /** 456 * Count number of bits set to one in x 457 * @param x value to count bits of 458 * @return the number of bits set to one in x 459 */ 460 static av_always_inline av_const int av_popcount64_c(uint64_t x) 461 { 462 return av_popcount((uint32_t)x) + av_popcount((uint32_t)(x >> 32)); 463 } 464 465 static av_always_inline av_const int av_parity_c(uint32_t v) 466 { 467 return av_popcount(v) & 1; 468 } 469 470 /** 471 * Convert a UTF-8 character (up to 4 bytes) to its 32-bit UCS-4 encoded form. 472 * 473 * @param val Output value, must be an lvalue of type uint32_t. 474 * @param GET_BYTE Expression reading one byte from the input. 475 * Evaluated up to 7 times (4 for the currently 476 * assigned Unicode range). With a memory buffer 477 * input, this could be *ptr++, or if you want to make sure 478 * that *ptr stops at the end of a NULL terminated string then 479 * *ptr ? *ptr++ : 0 480 * @param ERROR Expression to be evaluated on invalid input, 481 * typically a goto statement. 482 * 483 * @warning ERROR should not contain a loop control statement which 484 * could interact with the internal while loop, and should force an 485 * exit from the macro code (e.g. through a goto or a return) in order 486 * to prevent undefined results. 487 */ 488 #define GET_UTF8(val, GET_BYTE, ERROR)\ 489 val= (GET_BYTE);\ 490 {\ 491 uint32_t top = (val & 128) >> 1;\ 492 if ((val & 0xc0) == 0x80 || val >= 0xFE)\ 493 {ERROR}\ 494 while (val & top) {\ 495 unsigned int tmp = (GET_BYTE) - 128;\ 496 if(tmp>>6)\ 497 {ERROR}\ 498 val= (val<<6) + tmp;\ 499 top <<= 5;\ 500 }\ 501 val &= (top << 1) - 1;\ 502 } 503 504 /** 505 * Convert a UTF-16 character (2 or 4 bytes) to its 32-bit UCS-4 encoded form. 506 * 507 * @param val Output value, must be an lvalue of type uint32_t. 508 * @param GET_16BIT Expression returning two bytes of UTF-16 data converted 509 * to native byte order. Evaluated one or two times. 510 * @param ERROR Expression to be evaluated on invalid input, 511 * typically a goto statement. 512 */ 513 #define GET_UTF16(val, GET_16BIT, ERROR)\ 514 val = (GET_16BIT);\ 515 {\ 516 unsigned int hi = val - 0xD800;\ 517 if (hi < 0x800) {\ 518 val = (GET_16BIT) - 0xDC00;\ 519 if (val > 0x3FFU || hi > 0x3FFU)\ 520 {ERROR}\ 521 val += (hi<<10) + 0x10000;\ 522 }\ 523 }\ 524 525 /** 526 * @def PUT_UTF8(val, tmp, PUT_BYTE) 527 * Convert a 32-bit Unicode character to its UTF-8 encoded form (up to 4 bytes long). 528 * @param val is an input-only argument and should be of type uint32_t. It holds 529 * a UCS-4 encoded Unicode character that is to be converted to UTF-8. If 530 * val is given as a function it is executed only once. 531 * @param tmp is a temporary variable and should be of type uint8_t. It 532 * represents an intermediate value during conversion that is to be 533 * output by PUT_BYTE. 534 * @param PUT_BYTE writes the converted UTF-8 bytes to any proper destination. 535 * It could be a function or a statement, and uses tmp as the input byte. 536 * For example, PUT_BYTE could be "*output++ = tmp;" PUT_BYTE will be 537 * executed up to 4 times for values in the valid UTF-8 range and up to 538 * 7 times in the general case, depending on the length of the converted 539 * Unicode character. 540 */ 541 #define PUT_UTF8(val, tmp, PUT_BYTE)\ 542 {\ 543 int bytes, shift;\ 544 uint32_t in = val;\ 545 if (in < 0x80) {\ 546 tmp = in;\ 547 PUT_BYTE\ 548 } else {\ 549 bytes = (av_log2(in) + 4) / 5;\ 550 shift = (bytes - 1) * 6;\ 551 tmp = (256 - (256 >> bytes)) | (in >> shift);\ 552 PUT_BYTE\ 553 while (shift >= 6) {\ 554 shift -= 6;\ 555 tmp = 0x80 | ((in >> shift) & 0x3f);\ 556 PUT_BYTE\ 557 }\ 558 }\ 559 } 560 561 /** 562 * @def PUT_UTF16(val, tmp, PUT_16BIT) 563 * Convert a 32-bit Unicode character to its UTF-16 encoded form (2 or 4 bytes). 564 * @param val is an input-only argument and should be of type uint32_t. It holds 565 * a UCS-4 encoded Unicode character that is to be converted to UTF-16. If 566 * val is given as a function it is executed only once. 567 * @param tmp is a temporary variable and should be of type uint16_t. It 568 * represents an intermediate value during conversion that is to be 569 * output by PUT_16BIT. 570 * @param PUT_16BIT writes the converted UTF-16 data to any proper destination 571 * in desired endianness. It could be a function or a statement, and uses tmp 572 * as the input byte. For example, PUT_BYTE could be "*output++ = tmp;" 573 * PUT_BYTE will be executed 1 or 2 times depending on input character. 574 */ 575 #define PUT_UTF16(val, tmp, PUT_16BIT)\ 576 {\ 577 uint32_t in = val;\ 578 if (in < 0x10000) {\ 579 tmp = in;\ 580 PUT_16BIT\ 581 } else {\ 582 tmp = 0xD800 | ((in - 0x10000) >> 10);\ 583 PUT_16BIT\ 584 tmp = 0xDC00 | ((in - 0x10000) & 0x3FF);\ 585 PUT_16BIT\ 586 }\ 587 }\ 588 589 #endif /* AVUTIL_COMMON_H */