common.h (15500B)
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 "macros.h" 44 #include "version.h" 45 #include "libavutil/avconfig.h" 46 47 #if AV_HAVE_BIGENDIAN 48 # define AV_NE(be, le) (be) 49 #else 50 # define AV_NE(be, le) (le) 51 #endif 52 53 //rounded division & shift 54 #define RSHIFT(a,b) ((a) > 0 ? ((a) + ((1<<(b))>>1))>>(b) : ((a) + ((1<<(b))>>1)-1)>>(b)) 55 /* assume b>0 */ 56 #define ROUNDED_DIV(a,b) (((a)>0 ? (a) + ((b)>>1) : (a) - ((b)>>1))/(b)) 57 /* assume a>0 and b>0 */ 58 #define FF_CEIL_RSHIFT(a,b) (!av_builtin_constant_p(b) ? -((-(a)) >> (b)) \ 59 : ((a) + (1<<(b)) - 1) >> (b)) 60 #define FFUDIV(a,b) (((a)>0 ?(a):(a)-(b)+1) / (b)) 61 #define FFUMOD(a,b) ((a)-(b)*FFUDIV(a,b)) 62 63 /** 64 * Absolute value, Note, INT_MIN / INT64_MIN result in undefined behavior as they 65 * are not representable as absolute values of their type. This is the same 66 * as with *abs() 67 * @see FFNABS() 68 */ 69 #define FFABS(a) ((a) >= 0 ? (a) : (-(a))) 70 #define FFSIGN(a) ((a) > 0 ? 1 : -1) 71 72 /** 73 * Negative Absolute value. 74 * this works for all integers of all types. 75 * As with many macros, this evaluates its argument twice, it thus must not have 76 * a sideeffect, that is FFNABS(x++) has undefined behavior. 77 */ 78 #define FFNABS(a) ((a) <= 0 ? (a) : (-(a))) 79 80 /** 81 * Comparator. 82 * For two numerical expressions x and y, gives 1 if x > y, -1 if x < y, and 0 83 * if x == y. This is useful for instance in a qsort comparator callback. 84 * Furthermore, compilers are able to optimize this to branchless code, and 85 * there is no risk of overflow with signed types. 86 * As with many macros, this evaluates its argument multiple times, it thus 87 * must not have a side-effect. 88 */ 89 #define FFDIFFSIGN(x,y) (((x)>(y)) - ((x)<(y))) 90 91 #define FFMAX(a,b) ((a) > (b) ? (a) : (b)) 92 #define FFMAX3(a,b,c) FFMAX(FFMAX(a,b),c) 93 #define FFMIN(a,b) ((a) > (b) ? (b) : (a)) 94 #define FFMIN3(a,b,c) FFMIN(FFMIN(a,b),c) 95 96 #define FFSWAP(type,a,b) do{type SWAP_tmp= b; b= a; a= SWAP_tmp;}while(0) 97 #define FF_ARRAY_ELEMS(a) (sizeof(a) / sizeof((a)[0])) 98 99 /* misc math functions */ 100 101 #ifdef HAVE_AV_CONFIG_H 102 # include "config.h" 103 # include "intmath.h" 104 #endif 105 106 /* Pull in unguarded fallback defines at the end of this file. */ 107 #include "common.h" 108 109 #ifndef av_log2 110 av_const int av_log2(unsigned v); 111 #endif 112 113 #ifndef av_log2_16bit 114 av_const int av_log2_16bit(unsigned v); 115 #endif 116 117 /** 118 * Clip a signed integer value into the amin-amax range. 119 * @param a value to clip 120 * @param amin minimum value of the clip range 121 * @param amax maximum value of the clip range 122 * @return clipped value 123 */ 124 static av_always_inline av_const int av_clip_c(int a, int amin, int amax) 125 { 126 #if defined(HAVE_AV_CONFIG_H) && defined(ASSERT_LEVEL) && ASSERT_LEVEL >= 2 127 if (amin > amax) abort(); 128 #endif 129 if (a < amin) return amin; 130 else if (a > amax) return amax; 131 else return a; 132 } 133 134 /** 135 * Clip a signed 64bit integer value into the amin-amax range. 136 * @param a value to clip 137 * @param amin minimum value of the clip range 138 * @param amax maximum value of the clip range 139 * @return clipped value 140 */ 141 static av_always_inline av_const int64_t av_clip64_c(int64_t a, int64_t amin, int64_t amax) 142 { 143 #if defined(HAVE_AV_CONFIG_H) && defined(ASSERT_LEVEL) && ASSERT_LEVEL >= 2 144 if (amin > amax) abort(); 145 #endif 146 if (a < amin) return amin; 147 else if (a > amax) return amax; 148 else return a; 149 } 150 151 /** 152 * Clip a signed integer value into the 0-255 range. 153 * @param a value to clip 154 * @return clipped value 155 */ 156 static av_always_inline av_const uint8_t av_clip_uint8_c(int a) 157 { 158 if (a&(~0xFF)) return (-a)>>31; 159 else return a; 160 } 161 162 /** 163 * Clip a signed integer value into the -128,127 range. 164 * @param a value to clip 165 * @return clipped value 166 */ 167 static av_always_inline av_const int8_t av_clip_int8_c(int a) 168 { 169 if ((a+0x80U) & ~0xFF) return (a>>31) ^ 0x7F; 170 else return a; 171 } 172 173 /** 174 * Clip a signed integer value into the 0-65535 range. 175 * @param a value to clip 176 * @return clipped value 177 */ 178 static av_always_inline av_const uint16_t av_clip_uint16_c(int a) 179 { 180 if (a&(~0xFFFF)) return (-a)>>31; 181 else return a; 182 } 183 184 /** 185 * Clip a signed integer value into the -32768,32767 range. 186 * @param a value to clip 187 * @return clipped value 188 */ 189 static av_always_inline av_const int16_t av_clip_int16_c(int a) 190 { 191 if ((a+0x8000U) & ~0xFFFF) return (a>>31) ^ 0x7FFF; 192 else return a; 193 } 194 195 /** 196 * Clip a signed 64-bit integer value into the -2147483648,2147483647 range. 197 * @param a value to clip 198 * @return clipped value 199 */ 200 static av_always_inline av_const int32_t av_clipl_int32_c(int64_t a) 201 { 202 if ((a+0x80000000u) & ~UINT64_C(0xFFFFFFFF)) return (int32_t)((a>>63) ^ 0x7FFFFFFF); 203 else return (int32_t)a; 204 } 205 206 /** 207 * Clip a signed integer into the -(2^p),(2^p-1) range. 208 * @param a value to clip 209 * @param p bit position to clip at 210 * @return clipped value 211 */ 212 static av_always_inline av_const int av_clip_intp2_c(int a, int p) 213 { 214 if ((a + (1 << p)) & ~((2 << p) - 1)) 215 return (a >> 31) ^ ((1 << p) - 1); 216 else 217 return a; 218 } 219 220 /** 221 * Clip a signed integer to an unsigned power of two range. 222 * @param a value to clip 223 * @param p bit position to clip at 224 * @return clipped value 225 */ 226 static av_always_inline av_const unsigned av_clip_uintp2_c(int a, int p) 227 { 228 if (a & ~((1<<p) - 1)) return -a >> 31 & ((1<<p) - 1); 229 else return a; 230 } 231 232 /** 233 * Clear high bits from an unsigned integer starting with specific bit position 234 * @param a value to clip 235 * @param p bit position to clip at 236 * @return clipped value 237 */ 238 static av_always_inline av_const unsigned av_mod_uintp2_c(unsigned a, unsigned p) 239 { 240 return a & ((1 << p) - 1); 241 } 242 243 /** 244 * Add two signed 32-bit values with saturation. 245 * 246 * @param a one value 247 * @param b another value 248 * @return sum with signed saturation 249 */ 250 static av_always_inline int av_sat_add32_c(int a, int b) 251 { 252 return av_clipl_int32((int64_t)a + b); 253 } 254 255 /** 256 * Add a doubled value to another value with saturation at both stages. 257 * 258 * @param a first value 259 * @param b value doubled and added to a 260 * @return sum with signed saturation 261 */ 262 static av_always_inline int av_sat_dadd32_c(int a, int b) 263 { 264 return av_sat_add32(a, av_sat_add32(b, b)); 265 } 266 267 /** 268 * Clip a float value into the amin-amax range. 269 * @param a value to clip 270 * @param amin minimum value of the clip range 271 * @param amax maximum value of the clip range 272 * @return clipped value 273 */ 274 static av_always_inline av_const float av_clipf_c(float a, float amin, float amax) 275 { 276 #if defined(HAVE_AV_CONFIG_H) && defined(ASSERT_LEVEL) && ASSERT_LEVEL >= 2 277 if (amin > amax) abort(); 278 #endif 279 if (a < amin) return amin; 280 else if (a > amax) return amax; 281 else return a; 282 } 283 284 /** 285 * Clip a double value into the amin-amax range. 286 * @param a value to clip 287 * @param amin minimum value of the clip range 288 * @param amax maximum value of the clip range 289 * @return clipped value 290 */ 291 static av_always_inline av_const double av_clipd_c(double a, double amin, double amax) 292 { 293 #if defined(HAVE_AV_CONFIG_H) && defined(ASSERT_LEVEL) && ASSERT_LEVEL >= 2 294 if (amin > amax) abort(); 295 #endif 296 if (a < amin) return amin; 297 else if (a > amax) return amax; 298 else return a; 299 } 300 301 /** Compute ceil(log2(x)). 302 * @param x value used to compute ceil(log2(x)) 303 * @return computed ceiling of log2(x) 304 */ 305 static av_always_inline av_const int av_ceil_log2_c(int x) 306 { 307 return av_log2((x - 1) << 1); 308 } 309 310 /** 311 * Count number of bits set to one in x 312 * @param x value to count bits of 313 * @return the number of bits set to one in x 314 */ 315 static av_always_inline av_const int av_popcount_c(uint32_t x) 316 { 317 x -= (x >> 1) & 0x55555555; 318 x = (x & 0x33333333) + ((x >> 2) & 0x33333333); 319 x = (x + (x >> 4)) & 0x0F0F0F0F; 320 x += x >> 8; 321 return (x + (x >> 16)) & 0x3F; 322 } 323 324 /** 325 * Count number of bits set to one in x 326 * @param x value to count bits of 327 * @return the number of bits set to one in x 328 */ 329 static av_always_inline av_const int av_popcount64_c(uint64_t x) 330 { 331 return av_popcount((uint32_t)x) + av_popcount((uint32_t)(x >> 32)); 332 } 333 334 #define MKTAG(a,b,c,d) ((a) | ((b) << 8) | ((c) << 16) | ((unsigned)(d) << 24)) 335 #define MKBETAG(a,b,c,d) ((d) | ((c) << 8) | ((b) << 16) | ((unsigned)(a) << 24)) 336 337 /** 338 * Convert a UTF-8 character (up to 4 bytes) to its 32-bit UCS-4 encoded form. 339 * 340 * @param val Output value, must be an lvalue of type uint32_t. 341 * @param GET_BYTE Expression reading one byte from the input. 342 * Evaluated up to 7 times (4 for the currently 343 * assigned Unicode range). With a memory buffer 344 * input, this could be *ptr++. 345 * @param ERROR Expression to be evaluated on invalid input, 346 * typically a goto statement. 347 * 348 * @warning ERROR should not contain a loop control statement which 349 * could interact with the internal while loop, and should force an 350 * exit from the macro code (e.g. through a goto or a return) in order 351 * to prevent undefined results. 352 */ 353 #define GET_UTF8(val, GET_BYTE, ERROR)\ 354 val= GET_BYTE;\ 355 {\ 356 uint32_t top = (val & 128) >> 1;\ 357 if ((val & 0xc0) == 0x80 || val >= 0xFE)\ 358 ERROR\ 359 while (val & top) {\ 360 int tmp= GET_BYTE - 128;\ 361 if(tmp>>6)\ 362 ERROR\ 363 val= (val<<6) + tmp;\ 364 top <<= 5;\ 365 }\ 366 val &= (top << 1) - 1;\ 367 } 368 369 /** 370 * Convert a UTF-16 character (2 or 4 bytes) to its 32-bit UCS-4 encoded form. 371 * 372 * @param val Output value, must be an lvalue of type uint32_t. 373 * @param GET_16BIT Expression returning two bytes of UTF-16 data converted 374 * to native byte order. Evaluated one or two times. 375 * @param ERROR Expression to be evaluated on invalid input, 376 * typically a goto statement. 377 */ 378 #define GET_UTF16(val, GET_16BIT, ERROR)\ 379 val = GET_16BIT;\ 380 {\ 381 unsigned int hi = val - 0xD800;\ 382 if (hi < 0x800) {\ 383 val = GET_16BIT - 0xDC00;\ 384 if (val > 0x3FFU || hi > 0x3FFU)\ 385 ERROR\ 386 val += (hi<<10) + 0x10000;\ 387 }\ 388 }\ 389 390 /** 391 * @def PUT_UTF8(val, tmp, PUT_BYTE) 392 * Convert a 32-bit Unicode character to its UTF-8 encoded form (up to 4 bytes long). 393 * @param val is an input-only argument and should be of type uint32_t. It holds 394 * a UCS-4 encoded Unicode character that is to be converted to UTF-8. If 395 * val is given as a function it is executed only once. 396 * @param tmp is a temporary variable and should be of type uint8_t. It 397 * represents an intermediate value during conversion that is to be 398 * output by PUT_BYTE. 399 * @param PUT_BYTE writes the converted UTF-8 bytes to any proper destination. 400 * It could be a function or a statement, and uses tmp as the input byte. 401 * For example, PUT_BYTE could be "*output++ = tmp;" PUT_BYTE will be 402 * executed up to 4 times for values in the valid UTF-8 range and up to 403 * 7 times in the general case, depending on the length of the converted 404 * Unicode character. 405 */ 406 #define PUT_UTF8(val, tmp, PUT_BYTE)\ 407 {\ 408 int bytes, shift;\ 409 uint32_t in = val;\ 410 if (in < 0x80) {\ 411 tmp = in;\ 412 PUT_BYTE\ 413 } else {\ 414 bytes = (av_log2(in) + 4) / 5;\ 415 shift = (bytes - 1) * 6;\ 416 tmp = (256 - (256 >> bytes)) | (in >> shift);\ 417 PUT_BYTE\ 418 while (shift >= 6) {\ 419 shift -= 6;\ 420 tmp = 0x80 | ((in >> shift) & 0x3f);\ 421 PUT_BYTE\ 422 }\ 423 }\ 424 } 425 426 /** 427 * @def PUT_UTF16(val, tmp, PUT_16BIT) 428 * Convert a 32-bit Unicode character to its UTF-16 encoded form (2 or 4 bytes). 429 * @param val is an input-only argument and should be of type uint32_t. It holds 430 * a UCS-4 encoded Unicode character that is to be converted to UTF-16. If 431 * val is given as a function it is executed only once. 432 * @param tmp is a temporary variable and should be of type uint16_t. It 433 * represents an intermediate value during conversion that is to be 434 * output by PUT_16BIT. 435 * @param PUT_16BIT writes the converted UTF-16 data to any proper destination 436 * in desired endianness. It could be a function or a statement, and uses tmp 437 * as the input byte. For example, PUT_BYTE could be "*output++ = tmp;" 438 * PUT_BYTE will be executed 1 or 2 times depending on input character. 439 */ 440 #define PUT_UTF16(val, tmp, PUT_16BIT)\ 441 {\ 442 uint32_t in = val;\ 443 if (in < 0x10000) {\ 444 tmp = in;\ 445 PUT_16BIT\ 446 } else {\ 447 tmp = 0xD800 | ((in - 0x10000) >> 10);\ 448 PUT_16BIT\ 449 tmp = 0xDC00 | ((in - 0x10000) & 0x3FF);\ 450 PUT_16BIT\ 451 }\ 452 }\ 453 454 455 456 #include "mem.h" 457 458 #ifdef HAVE_AV_CONFIG_H 459 # include "internal.h" 460 #endif /* HAVE_AV_CONFIG_H */ 461 462 #endif /* AVUTIL_COMMON_H */ 463 464 /* 465 * The following definitions are outside the multiple inclusion guard 466 * to ensure they are immediately available in intmath.h. 467 */ 468 469 #ifndef av_ceil_log2 470 # define av_ceil_log2 av_ceil_log2_c 471 #endif 472 #ifndef av_clip 473 # define av_clip av_clip_c 474 #endif 475 #ifndef av_clip64 476 # define av_clip64 av_clip64_c 477 #endif 478 #ifndef av_clip_uint8 479 # define av_clip_uint8 av_clip_uint8_c 480 #endif 481 #ifndef av_clip_int8 482 # define av_clip_int8 av_clip_int8_c 483 #endif 484 #ifndef av_clip_uint16 485 # define av_clip_uint16 av_clip_uint16_c 486 #endif 487 #ifndef av_clip_int16 488 # define av_clip_int16 av_clip_int16_c 489 #endif 490 #ifndef av_clipl_int32 491 # define av_clipl_int32 av_clipl_int32_c 492 #endif 493 #ifndef av_clip_intp2 494 # define av_clip_intp2 av_clip_intp2_c 495 #endif 496 #ifndef av_clip_uintp2 497 # define av_clip_uintp2 av_clip_uintp2_c 498 #endif 499 #ifndef av_mod_uintp2 500 # define av_mod_uintp2 av_mod_uintp2_c 501 #endif 502 #ifndef av_sat_add32 503 # define av_sat_add32 av_sat_add32_c 504 #endif 505 #ifndef av_sat_dadd32 506 # define av_sat_dadd32 av_sat_dadd32_c 507 #endif 508 #ifndef av_clipf 509 # define av_clipf av_clipf_c 510 #endif 511 #ifndef av_clipd 512 # define av_clipd av_clipd_c 513 #endif 514 #ifndef av_popcount 515 # define av_popcount av_popcount_c 516 #endif 517 #ifndef av_popcount64 518 # define av_popcount64 av_popcount64_c 519 #endif