common.h (11759B)
1 /* 2 * copyright (c) 2006 Michael Niedermayer <michaelni@gmx.at> 3 * 4 * This file is part of Libav. 5 * 6 * Libav 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 * Libav 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 Libav; 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 #include <errno.h> 30 #include <inttypes.h> 31 #include <limits.h> 32 #include <math.h> 33 #include <stdint.h> 34 #include <stdio.h> 35 #include <stdlib.h> 36 #include <string.h> 37 38 #include "attributes.h" 39 #include "version.h" 40 #include "libavutil/avconfig.h" 41 42 #if AV_HAVE_BIGENDIAN 43 # define AV_NE(be, le) (be) 44 #else 45 # define AV_NE(be, le) (le) 46 #endif 47 48 //rounded division & shift 49 #define RSHIFT(a,b) ((a) > 0 ? ((a) + ((1<<(b))>>1))>>(b) : ((a) + ((1<<(b))>>1)-1)>>(b)) 50 /* assume b>0 */ 51 #define ROUNDED_DIV(a,b) (((a)>0 ? (a) + ((b)>>1) : (a) - ((b)>>1))/(b)) 52 #define FFABS(a) ((a) >= 0 ? (a) : (-(a))) 53 #define FFSIGN(a) ((a) > 0 ? 1 : -1) 54 55 #define FFMAX(a,b) ((a) > (b) ? (a) : (b)) 56 #define FFMAX3(a,b,c) FFMAX(FFMAX(a,b),c) 57 #define FFMIN(a,b) ((a) > (b) ? (b) : (a)) 58 #define FFMIN3(a,b,c) FFMIN(FFMIN(a,b),c) 59 60 #define FFSWAP(type,a,b) do{type SWAP_tmp= b; b= a; a= SWAP_tmp;}while(0) 61 #define FF_ARRAY_ELEMS(a) (sizeof(a) / sizeof((a)[0])) 62 #define FFALIGN(x, a) (((x)+(a)-1)&~((a)-1)) 63 64 /* misc math functions */ 65 66 #if FF_API_AV_REVERSE 67 extern attribute_deprecated const uint8_t av_reverse[256]; 68 #endif 69 70 #ifdef HAVE_AV_CONFIG_H 71 # include "config.h" 72 # include "intmath.h" 73 #endif 74 75 /* Pull in unguarded fallback defines at the end of this file. */ 76 #include "common.h" 77 78 #ifndef av_log2 79 av_const int av_log2(unsigned v); 80 #endif 81 82 #ifndef av_log2_16bit 83 av_const int av_log2_16bit(unsigned v); 84 #endif 85 86 /** 87 * Clip a signed integer value into the amin-amax range. 88 * @param a value to clip 89 * @param amin minimum value of the clip range 90 * @param amax maximum value of the clip range 91 * @return clipped value 92 */ 93 static av_always_inline av_const int av_clip_c(int a, int amin, int amax) 94 { 95 if (a < amin) return amin; 96 else if (a > amax) return amax; 97 else return a; 98 } 99 100 /** 101 * Clip a signed integer value into the 0-255 range. 102 * @param a value to clip 103 * @return clipped value 104 */ 105 static av_always_inline av_const uint8_t av_clip_uint8_c(int a) 106 { 107 if (a&(~0xFF)) return (-a)>>31; 108 else return a; 109 } 110 111 /** 112 * Clip a signed integer value into the -128,127 range. 113 * @param a value to clip 114 * @return clipped value 115 */ 116 static av_always_inline av_const int8_t av_clip_int8_c(int a) 117 { 118 if ((a+0x80) & ~0xFF) return (a>>31) ^ 0x7F; 119 else return a; 120 } 121 122 /** 123 * Clip a signed integer value into the 0-65535 range. 124 * @param a value to clip 125 * @return clipped value 126 */ 127 static av_always_inline av_const uint16_t av_clip_uint16_c(int a) 128 { 129 if (a&(~0xFFFF)) return (-a)>>31; 130 else return a; 131 } 132 133 /** 134 * Clip a signed integer value into the -32768,32767 range. 135 * @param a value to clip 136 * @return clipped value 137 */ 138 static av_always_inline av_const int16_t av_clip_int16_c(int a) 139 { 140 if ((a+0x8000) & ~0xFFFF) return (a>>31) ^ 0x7FFF; 141 else return a; 142 } 143 144 /** 145 * Clip a signed 64-bit integer value into the -2147483648,2147483647 range. 146 * @param a value to clip 147 * @return clipped value 148 */ 149 static av_always_inline av_const int32_t av_clipl_int32_c(int64_t a) 150 { 151 if ((a+0x80000000u) & ~UINT64_C(0xFFFFFFFF)) return (a>>63) ^ 0x7FFFFFFF; 152 else return a; 153 } 154 155 /** 156 * Clip a signed integer to an unsigned power of two range. 157 * @param a value to clip 158 * @param p bit position to clip at 159 * @return clipped value 160 */ 161 static av_always_inline av_const unsigned av_clip_uintp2_c(int a, int p) 162 { 163 if (a & ~((1<<p) - 1)) return -a >> 31 & ((1<<p) - 1); 164 else return a; 165 } 166 167 /** 168 * Add two signed 32-bit values with saturation. 169 * 170 * @param a one value 171 * @param b another value 172 * @return sum with signed saturation 173 */ 174 static av_always_inline int av_sat_add32_c(int a, int b) 175 { 176 return av_clipl_int32((int64_t)a + b); 177 } 178 179 /** 180 * Add a doubled value to another value with saturation at both stages. 181 * 182 * @param a first value 183 * @param b value doubled and added to a 184 * @return sum with signed saturation 185 */ 186 static av_always_inline int av_sat_dadd32_c(int a, int b) 187 { 188 return av_sat_add32(a, av_sat_add32(b, b)); 189 } 190 191 /** 192 * Clip a float value into the amin-amax range. 193 * @param a value to clip 194 * @param amin minimum value of the clip range 195 * @param amax maximum value of the clip range 196 * @return clipped value 197 */ 198 static av_always_inline av_const float av_clipf_c(float a, float amin, float amax) 199 { 200 if (a < amin) return amin; 201 else if (a > amax) return amax; 202 else return a; 203 } 204 205 /** Compute ceil(log2(x)). 206 * @param x value used to compute ceil(log2(x)) 207 * @return computed ceiling of log2(x) 208 */ 209 static av_always_inline av_const int av_ceil_log2_c(int x) 210 { 211 return av_log2((x - 1) << 1); 212 } 213 214 /** 215 * Count number of bits set to one in x 216 * @param x value to count bits of 217 * @return the number of bits set to one in x 218 */ 219 static av_always_inline av_const int av_popcount_c(uint32_t x) 220 { 221 x -= (x >> 1) & 0x55555555; 222 x = (x & 0x33333333) + ((x >> 2) & 0x33333333); 223 x = (x + (x >> 4)) & 0x0F0F0F0F; 224 x += x >> 8; 225 return (x + (x >> 16)) & 0x3F; 226 } 227 228 /** 229 * Count number of bits set to one in x 230 * @param x value to count bits of 231 * @return the number of bits set to one in x 232 */ 233 static av_always_inline av_const int av_popcount64_c(uint64_t x) 234 { 235 return av_popcount(x) + av_popcount(x >> 32); 236 } 237 238 #define MKTAG(a,b,c,d) ((a) | ((b) << 8) | ((c) << 16) | ((unsigned)(d) << 24)) 239 #define MKBETAG(a,b,c,d) ((d) | ((c) << 8) | ((b) << 16) | ((unsigned)(a) << 24)) 240 241 /** 242 * Convert a UTF-8 character (up to 4 bytes) to its 32-bit UCS-4 encoded form. 243 * 244 * @param val Output value, must be an lvalue of type uint32_t. 245 * @param GET_BYTE Expression reading one byte from the input. 246 * Evaluated up to 7 times (4 for the currently 247 * assigned Unicode range). With a memory buffer 248 * input, this could be *ptr++. 249 * @param ERROR Expression to be evaluated on invalid input, 250 * typically a goto statement. 251 */ 252 #define GET_UTF8(val, GET_BYTE, ERROR)\ 253 val= GET_BYTE;\ 254 {\ 255 uint32_t top = (val & 128) >> 1;\ 256 if ((val & 0xc0) == 0x80)\ 257 ERROR\ 258 while (val & top) {\ 259 int tmp= GET_BYTE - 128;\ 260 if(tmp>>6)\ 261 ERROR\ 262 val= (val<<6) + tmp;\ 263 top <<= 5;\ 264 }\ 265 val &= (top << 1) - 1;\ 266 } 267 268 /** 269 * Convert a UTF-16 character (2 or 4 bytes) to its 32-bit UCS-4 encoded form. 270 * 271 * @param val Output value, must be an lvalue of type uint32_t. 272 * @param GET_16BIT Expression returning two bytes of UTF-16 data converted 273 * to native byte order. Evaluated one or two times. 274 * @param ERROR Expression to be evaluated on invalid input, 275 * typically a goto statement. 276 */ 277 #define GET_UTF16(val, GET_16BIT, ERROR)\ 278 val = GET_16BIT;\ 279 {\ 280 unsigned int hi = val - 0xD800;\ 281 if (hi < 0x800) {\ 282 val = GET_16BIT - 0xDC00;\ 283 if (val > 0x3FFU || hi > 0x3FFU)\ 284 ERROR\ 285 val += (hi<<10) + 0x10000;\ 286 }\ 287 }\ 288 289 /** 290 * @def PUT_UTF8(val, tmp, PUT_BYTE) 291 * Convert a 32-bit Unicode character to its UTF-8 encoded form (up to 4 bytes long). 292 * @param val is an input-only argument and should be of type uint32_t. It holds 293 * a UCS-4 encoded Unicode character that is to be converted to UTF-8. If 294 * val is given as a function it is executed only once. 295 * @param tmp is a temporary variable and should be of type uint8_t. It 296 * represents an intermediate value during conversion that is to be 297 * output by PUT_BYTE. 298 * @param PUT_BYTE writes the converted UTF-8 bytes to any proper destination. 299 * It could be a function or a statement, and uses tmp as the input byte. 300 * For example, PUT_BYTE could be "*output++ = tmp;" PUT_BYTE will be 301 * executed up to 4 times for values in the valid UTF-8 range and up to 302 * 7 times in the general case, depending on the length of the converted 303 * Unicode character. 304 */ 305 #define PUT_UTF8(val, tmp, PUT_BYTE)\ 306 {\ 307 int bytes, shift;\ 308 uint32_t in = val;\ 309 if (in < 0x80) {\ 310 tmp = in;\ 311 PUT_BYTE\ 312 } else {\ 313 bytes = (av_log2(in) + 4) / 5;\ 314 shift = (bytes - 1) * 6;\ 315 tmp = (256 - (256 >> bytes)) | (in >> shift);\ 316 PUT_BYTE\ 317 while (shift >= 6) {\ 318 shift -= 6;\ 319 tmp = 0x80 | ((in >> shift) & 0x3f);\ 320 PUT_BYTE\ 321 }\ 322 }\ 323 } 324 325 /** 326 * @def PUT_UTF16(val, tmp, PUT_16BIT) 327 * Convert a 32-bit Unicode character to its UTF-16 encoded form (2 or 4 bytes). 328 * @param val is an input-only argument and should be of type uint32_t. It holds 329 * a UCS-4 encoded Unicode character that is to be converted to UTF-16. If 330 * val is given as a function it is executed only once. 331 * @param tmp is a temporary variable and should be of type uint16_t. It 332 * represents an intermediate value during conversion that is to be 333 * output by PUT_16BIT. 334 * @param PUT_16BIT writes the converted UTF-16 data to any proper destination 335 * in desired endianness. It could be a function or a statement, and uses tmp 336 * as the input byte. For example, PUT_BYTE could be "*output++ = tmp;" 337 * PUT_BYTE will be executed 1 or 2 times depending on input character. 338 */ 339 #define PUT_UTF16(val, tmp, PUT_16BIT)\ 340 {\ 341 uint32_t in = val;\ 342 if (in < 0x10000) {\ 343 tmp = in;\ 344 PUT_16BIT\ 345 } else {\ 346 tmp = 0xD800 | ((in - 0x10000) >> 10);\ 347 PUT_16BIT\ 348 tmp = 0xDC00 | ((in - 0x10000) & 0x3FF);\ 349 PUT_16BIT\ 350 }\ 351 }\ 352 353 354 355 #include "mem.h" 356 357 #ifdef HAVE_AV_CONFIG_H 358 # include "internal.h" 359 #endif /* HAVE_AV_CONFIG_H */ 360 361 #endif /* AVUTIL_COMMON_H */ 362 363 /* 364 * The following definitions are outside the multiple inclusion guard 365 * to ensure they are immediately available in intmath.h. 366 */ 367 368 #ifndef av_ceil_log2 369 # define av_ceil_log2 av_ceil_log2_c 370 #endif 371 #ifndef av_clip 372 # define av_clip av_clip_c 373 #endif 374 #ifndef av_clip_uint8 375 # define av_clip_uint8 av_clip_uint8_c 376 #endif 377 #ifndef av_clip_int8 378 # define av_clip_int8 av_clip_int8_c 379 #endif 380 #ifndef av_clip_uint16 381 # define av_clip_uint16 av_clip_uint16_c 382 #endif 383 #ifndef av_clip_int16 384 # define av_clip_int16 av_clip_int16_c 385 #endif 386 #ifndef av_clipl_int32 387 # define av_clipl_int32 av_clipl_int32_c 388 #endif 389 #ifndef av_clip_uintp2 390 # define av_clip_uintp2 av_clip_uintp2_c 391 #endif 392 #ifndef av_sat_add32 393 # define av_sat_add32 av_sat_add32_c 394 #endif 395 #ifndef av_sat_dadd32 396 # define av_sat_dadd32 av_sat_dadd32_c 397 #endif 398 #ifndef av_clipf 399 # define av_clipf av_clipf_c 400 #endif 401 #ifndef av_popcount 402 # define av_popcount av_popcount_c 403 #endif 404 #ifndef av_popcount64 405 # define av_popcount64 av_popcount64_c 406 #endif