bitwriter.c revision c74663799493f2b1e6123c18def94295d0afab7b
1/* libFLAC - Free Lossless Audio Codec library 2 * Copyright (C) 2000,2001,2002,2003,2004,2005,2006,2007 Josh Coalson 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * 8 * - Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 11 * - Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * - Neither the name of the Xiph.org Foundation nor the names of its 16 * contributors may be used to endorse or promote products derived from 17 * this software without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 21 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 22 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR 23 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 24 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 25 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR 26 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF 27 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING 28 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS 29 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 30 */ 31 32#if HAVE_CONFIG_H 33# include <config.h> 34#endif 35 36#include <stdlib.h> /* for malloc() */ 37#include <string.h> /* for memcpy(), memset() */ 38#ifdef _MSC_VER 39#include <winsock.h> /* for ntohl() */ 40#elif defined FLAC__SYS_DARWIN 41#include <machine/endian.h> /* for ntohl() */ 42#elif defined __MINGW32__ 43#include <winsock.h> /* for ntohl() */ 44#else 45#include <netinet/in.h> /* for ntohl() */ 46#endif 47#if 0 /* UNUSED */ 48#include "private/bitmath.h" 49#endif 50#include "private/bitwriter.h" 51#include "private/crc.h" 52#include "FLAC/assert.h" 53#include "share/alloc.h" 54 55/* Things should be fastest when this matches the machine word size */ 56/* WATCHOUT: if you change this you must also change the following #defines down to SWAP_BE_WORD_TO_HOST below to match */ 57/* WATCHOUT: there are a few places where the code will not work unless bwword is >= 32 bits wide */ 58typedef FLAC__uint32 bwword; 59#define FLAC__BYTES_PER_WORD 4 60#define FLAC__BITS_PER_WORD 32 61#define FLAC__WORD_ALL_ONES ((FLAC__uint32)0xffffffff) 62/* SWAP_BE_WORD_TO_HOST swaps bytes in a bwword (which is always big-endian) if necessary to match host byte order */ 63#if WORDS_BIGENDIAN 64#define SWAP_BE_WORD_TO_HOST(x) (x) 65#else 66#ifdef _MSC_VER 67#define SWAP_BE_WORD_TO_HOST(x) local_swap32_(x) 68#else 69#define SWAP_BE_WORD_TO_HOST(x) ntohl(x) 70#endif 71#endif 72 73/* 74 * The default capacity here doesn't matter too much. The buffer always grows 75 * to hold whatever is written to it. Usually the encoder will stop adding at 76 * a frame or metadata block, then write that out and clear the buffer for the 77 * next one. 78 */ 79static const unsigned FLAC__BITWRITER_DEFAULT_CAPACITY = 32768u / sizeof(bwword); /* size in words */ 80/* When growing, increment 4K at a time */ 81static const unsigned FLAC__BITWRITER_DEFAULT_INCREMENT = 4096u / sizeof(bwword); /* size in words */ 82 83#define FLAC__WORDS_TO_BITS(words) ((words) * FLAC__BITS_PER_WORD) 84#define FLAC__TOTAL_BITS(bw) (FLAC__WORDS_TO_BITS((bw)->words) + (bw)->bits) 85 86#ifdef min 87#undef min 88#endif 89#define min(x,y) ((x)<(y)?(x):(y)) 90 91/* adjust for compilers that can't understand using LLU suffix for uint64_t literals */ 92#ifdef _MSC_VER 93#define FLAC__U64L(x) x 94#else 95#define FLAC__U64L(x) x##LLU 96#endif 97 98#ifndef FLaC__INLINE 99#define FLaC__INLINE 100#endif 101 102struct FLAC__BitWriter { 103 bwword *buffer; 104 bwword accum; /* accumulator; bits are right-justified; when full, accum is appended to buffer */ 105 unsigned capacity; /* capacity of buffer in words */ 106 unsigned words; /* # of complete words in buffer */ 107 unsigned bits; /* # of used bits in accum */ 108}; 109 110#ifdef _MSC_VER 111/* OPT: an MSVC built-in would be better */ 112static _inline FLAC__uint32 local_swap32_(FLAC__uint32 x) 113{ 114 x = ((x<<8)&0xFF00FF00) | ((x>>8)&0x00FF00FF); 115 return (x>>16) | (x<<16); 116} 117#endif 118 119/* * WATCHOUT: The current implementation only grows the buffer. */ 120static FLAC__bool bitwriter_grow_(FLAC__BitWriter *bw, unsigned bits_to_add) 121{ 122 unsigned new_capacity; 123 bwword *new_buffer; 124 125 FLAC__ASSERT(0 != bw); 126 FLAC__ASSERT(0 != bw->buffer); 127 128 /* calculate total words needed to store 'bits_to_add' additional bits */ 129 new_capacity = bw->words + ((bw->bits + bits_to_add + FLAC__BITS_PER_WORD - 1) / FLAC__BITS_PER_WORD); 130 131 /* it's possible (due to pessimism in the growth estimation that 132 * leads to this call) that we don't actually need to grow 133 */ 134 if(bw->capacity >= new_capacity) 135 return true; 136 137 /* round up capacity increase to the nearest FLAC__BITWRITER_DEFAULT_INCREMENT */ 138 if((new_capacity - bw->capacity) % FLAC__BITWRITER_DEFAULT_INCREMENT) 139 new_capacity += FLAC__BITWRITER_DEFAULT_INCREMENT - ((new_capacity - bw->capacity) % FLAC__BITWRITER_DEFAULT_INCREMENT); 140 /* make sure we got everything right */ 141 FLAC__ASSERT(0 == (new_capacity - bw->capacity) % FLAC__BITWRITER_DEFAULT_INCREMENT); 142 FLAC__ASSERT(new_capacity > bw->capacity); 143 FLAC__ASSERT(new_capacity >= bw->words + ((bw->bits + bits_to_add + FLAC__BITS_PER_WORD - 1) / FLAC__BITS_PER_WORD)); 144 145 new_buffer = (bwword*)safe_realloc_mul_2op_(bw->buffer, sizeof(bwword), /*times*/new_capacity); 146 if(new_buffer == 0) 147 return false; 148 bw->buffer = new_buffer; 149 bw->capacity = new_capacity; 150 return true; 151} 152 153 154/*********************************************************************** 155 * 156 * Class constructor/destructor 157 * 158 ***********************************************************************/ 159 160FLAC__BitWriter *FLAC__bitwriter_new(void) 161{ 162 FLAC__BitWriter *bw = (FLAC__BitWriter*)calloc(1, sizeof(FLAC__BitWriter)); 163 /* note that calloc() sets all members to 0 for us */ 164 return bw; 165} 166 167void FLAC__bitwriter_delete(FLAC__BitWriter *bw) 168{ 169 FLAC__ASSERT(0 != bw); 170 171 FLAC__bitwriter_free(bw); 172 free(bw); 173} 174 175/*********************************************************************** 176 * 177 * Public class methods 178 * 179 ***********************************************************************/ 180 181FLAC__bool FLAC__bitwriter_init(FLAC__BitWriter *bw) 182{ 183 FLAC__ASSERT(0 != bw); 184 185 bw->words = bw->bits = 0; 186 bw->capacity = FLAC__BITWRITER_DEFAULT_CAPACITY; 187 bw->buffer = (bwword*)malloc(sizeof(bwword) * bw->capacity); 188 if(bw->buffer == 0) 189 return false; 190 191 return true; 192} 193 194void FLAC__bitwriter_free(FLAC__BitWriter *bw) 195{ 196 FLAC__ASSERT(0 != bw); 197 198 if(0 != bw->buffer) 199 free(bw->buffer); 200 bw->buffer = 0; 201 bw->capacity = 0; 202 bw->words = bw->bits = 0; 203} 204 205void FLAC__bitwriter_clear(FLAC__BitWriter *bw) 206{ 207 bw->words = bw->bits = 0; 208} 209 210void FLAC__bitwriter_dump(const FLAC__BitWriter *bw, FILE *out) 211{ 212 unsigned i, j; 213 if(bw == 0) { 214 fprintf(out, "bitwriter is NULL\n"); 215 } 216 else { 217 fprintf(out, "bitwriter: capacity=%u words=%u bits=%u total_bits=%u\n", bw->capacity, bw->words, bw->bits, FLAC__TOTAL_BITS(bw)); 218 219 for(i = 0; i < bw->words; i++) { 220 fprintf(out, "%08X: ", i); 221 for(j = 0; j < FLAC__BITS_PER_WORD; j++) 222 fprintf(out, "%01u", bw->buffer[i] & (1 << (FLAC__BITS_PER_WORD-j-1)) ? 1:0); 223 fprintf(out, "\n"); 224 } 225 if(bw->bits > 0) { 226 fprintf(out, "%08X: ", i); 227 for(j = 0; j < bw->bits; j++) 228 fprintf(out, "%01u", bw->accum & (1 << (bw->bits-j-1)) ? 1:0); 229 fprintf(out, "\n"); 230 } 231 } 232} 233 234FLAC__bool FLAC__bitwriter_get_write_crc16(FLAC__BitWriter *bw, FLAC__uint16 *crc) 235{ 236 const FLAC__byte *buffer; 237 size_t bytes; 238 239 FLAC__ASSERT((bw->bits & 7) == 0); /* assert that we're byte-aligned */ 240 241 if(!FLAC__bitwriter_get_buffer(bw, &buffer, &bytes)) 242 return false; 243 244 *crc = (FLAC__uint16)FLAC__crc16(buffer, bytes); 245 FLAC__bitwriter_release_buffer(bw); 246 return true; 247} 248 249FLAC__bool FLAC__bitwriter_get_write_crc8(FLAC__BitWriter *bw, FLAC__byte *crc) 250{ 251 const FLAC__byte *buffer; 252 size_t bytes; 253 254 FLAC__ASSERT((bw->bits & 7) == 0); /* assert that we're byte-aligned */ 255 256 if(!FLAC__bitwriter_get_buffer(bw, &buffer, &bytes)) 257 return false; 258 259 *crc = FLAC__crc8(buffer, bytes); 260 FLAC__bitwriter_release_buffer(bw); 261 return true; 262} 263 264FLAC__bool FLAC__bitwriter_is_byte_aligned(const FLAC__BitWriter *bw) 265{ 266 return ((bw->bits & 7) == 0); 267} 268 269unsigned FLAC__bitwriter_get_input_bits_unconsumed(const FLAC__BitWriter *bw) 270{ 271 return FLAC__TOTAL_BITS(bw); 272} 273 274FLAC__bool FLAC__bitwriter_get_buffer(FLAC__BitWriter *bw, const FLAC__byte **buffer, size_t *bytes) 275{ 276 FLAC__ASSERT((bw->bits & 7) == 0); 277 /* double protection */ 278 if(bw->bits & 7) 279 return false; 280 /* if we have bits in the accumulator we have to flush those to the buffer first */ 281 if(bw->bits) { 282 FLAC__ASSERT(bw->words <= bw->capacity); 283 if(bw->words == bw->capacity && !bitwriter_grow_(bw, FLAC__BITS_PER_WORD)) 284 return false; 285 /* append bits as complete word to buffer, but don't change bw->accum or bw->bits */ 286 bw->buffer[bw->words] = SWAP_BE_WORD_TO_HOST(bw->accum << (FLAC__BITS_PER_WORD-bw->bits)); 287 } 288 /* now we can just return what we have */ 289 *buffer = (FLAC__byte*)bw->buffer; 290 *bytes = (FLAC__BYTES_PER_WORD * bw->words) + (bw->bits >> 3); 291 return true; 292} 293 294void FLAC__bitwriter_release_buffer(FLAC__BitWriter *bw) 295{ 296 /* nothing to do. in the future, strict checking of a 'writer-is-in- 297 * get-mode' flag could be added everywhere and then cleared here 298 */ 299 (void)bw; 300} 301 302FLaC__INLINE FLAC__bool FLAC__bitwriter_write_zeroes(FLAC__BitWriter *bw, unsigned bits) 303{ 304 unsigned n; 305 306 FLAC__ASSERT(0 != bw); 307 FLAC__ASSERT(0 != bw->buffer); 308 309 if(bits == 0) 310 return true; 311 /* slightly pessimistic size check but faster than "<= bw->words + (bw->bits+bits+FLAC__BITS_PER_WORD-1)/FLAC__BITS_PER_WORD" */ 312 if(bw->capacity <= bw->words + bits && !bitwriter_grow_(bw, bits)) 313 return false; 314 /* first part gets to word alignment */ 315 if(bw->bits) { 316 n = min(FLAC__BITS_PER_WORD - bw->bits, bits); 317 bw->accum <<= n; 318 bits -= n; 319 bw->bits += n; 320 if(bw->bits == FLAC__BITS_PER_WORD) { 321 bw->buffer[bw->words++] = SWAP_BE_WORD_TO_HOST(bw->accum); 322 bw->bits = 0; 323 } 324 else 325 return true; 326 } 327 /* do whole words */ 328 while(bits >= FLAC__BITS_PER_WORD) { 329 bw->buffer[bw->words++] = 0; 330 bits -= FLAC__BITS_PER_WORD; 331 } 332 /* do any leftovers */ 333 if(bits > 0) { 334 bw->accum = 0; 335 bw->bits = bits; 336 } 337 return true; 338} 339 340FLaC__INLINE FLAC__bool FLAC__bitwriter_write_raw_uint32(FLAC__BitWriter *bw, FLAC__uint32 val, unsigned bits) 341{ 342 register unsigned left; 343 344 /* WATCHOUT: code does not work with <32bit words; we can make things much faster with this assertion */ 345 FLAC__ASSERT(FLAC__BITS_PER_WORD >= 32); 346 347 FLAC__ASSERT(0 != bw); 348 FLAC__ASSERT(0 != bw->buffer); 349 350 FLAC__ASSERT(bits <= 32); 351 if(bits == 0) 352 return true; 353 354 /* slightly pessimistic size check but faster than "<= bw->words + (bw->bits+bits+FLAC__BITS_PER_WORD-1)/FLAC__BITS_PER_WORD" */ 355 if(bw->capacity <= bw->words + bits && !bitwriter_grow_(bw, bits)) 356 return false; 357 358 left = FLAC__BITS_PER_WORD - bw->bits; 359 if(bits < left) { 360 bw->accum <<= bits; 361 bw->accum |= val; 362 bw->bits += bits; 363 } 364 else if(bw->bits) { /* WATCHOUT: if bw->bits == 0, left==FLAC__BITS_PER_WORD and bw->accum<<=left is a NOP instead of setting to 0 */ 365 bw->accum <<= left; 366 bw->accum |= val >> (bw->bits = bits - left); 367 bw->buffer[bw->words++] = SWAP_BE_WORD_TO_HOST(bw->accum); 368 bw->accum = val; 369 } 370 else { 371 bw->accum = val; 372 bw->bits = 0; 373 bw->buffer[bw->words++] = SWAP_BE_WORD_TO_HOST(val); 374 } 375 376 return true; 377} 378 379FLaC__INLINE FLAC__bool FLAC__bitwriter_write_raw_int32(FLAC__BitWriter *bw, FLAC__int32 val, unsigned bits) 380{ 381 /* zero-out unused bits */ 382 if(bits < 32) 383 val &= (~(0xffffffff << bits)); 384 385 return FLAC__bitwriter_write_raw_uint32(bw, (FLAC__uint32)val, bits); 386} 387 388FLaC__INLINE FLAC__bool FLAC__bitwriter_write_raw_uint64(FLAC__BitWriter *bw, FLAC__uint64 val, unsigned bits) 389{ 390 /* this could be a little faster but it's not used for much */ 391 if(bits > 32) { 392 return 393 FLAC__bitwriter_write_raw_uint32(bw, (FLAC__uint32)(val>>32), bits-32) && 394 FLAC__bitwriter_write_raw_uint32(bw, (FLAC__uint32)val, 32); 395 } 396 else 397 return FLAC__bitwriter_write_raw_uint32(bw, (FLAC__uint32)val, bits); 398} 399 400FLaC__INLINE FLAC__bool FLAC__bitwriter_write_raw_uint32_little_endian(FLAC__BitWriter *bw, FLAC__uint32 val) 401{ 402 /* this doesn't need to be that fast as currently it is only used for vorbis comments */ 403 404 if(!FLAC__bitwriter_write_raw_uint32(bw, val & 0xff, 8)) 405 return false; 406 if(!FLAC__bitwriter_write_raw_uint32(bw, (val>>8) & 0xff, 8)) 407 return false; 408 if(!FLAC__bitwriter_write_raw_uint32(bw, (val>>16) & 0xff, 8)) 409 return false; 410 if(!FLAC__bitwriter_write_raw_uint32(bw, val>>24, 8)) 411 return false; 412 413 return true; 414} 415 416FLaC__INLINE FLAC__bool FLAC__bitwriter_write_byte_block(FLAC__BitWriter *bw, const FLAC__byte vals[], unsigned nvals) 417{ 418 unsigned i; 419 420 /* this could be faster but currently we don't need it to be since it's only used for writing metadata */ 421 for(i = 0; i < nvals; i++) { 422 if(!FLAC__bitwriter_write_raw_uint32(bw, (FLAC__uint32)(vals[i]), 8)) 423 return false; 424 } 425 426 return true; 427} 428 429FLAC__bool FLAC__bitwriter_write_unary_unsigned(FLAC__BitWriter *bw, unsigned val) 430{ 431 if(val < 32) 432 return FLAC__bitwriter_write_raw_uint32(bw, 1, ++val); 433 else 434 return 435 FLAC__bitwriter_write_zeroes(bw, val) && 436 FLAC__bitwriter_write_raw_uint32(bw, 1, 1); 437} 438 439unsigned FLAC__bitwriter_rice_bits(FLAC__int32 val, unsigned parameter) 440{ 441 FLAC__uint32 uval; 442 443 FLAC__ASSERT(parameter < sizeof(unsigned)*8); 444 445 /* fold signed to unsigned; actual formula is: negative(v)? -2v-1 : 2v */ 446 uval = (val<<1) ^ (val>>31); 447 448 return 1 + parameter + (uval >> parameter); 449} 450 451#if 0 /* UNUSED */ 452unsigned FLAC__bitwriter_golomb_bits_signed(int val, unsigned parameter) 453{ 454 unsigned bits, msbs, uval; 455 unsigned k; 456 457 FLAC__ASSERT(parameter > 0); 458 459 /* fold signed to unsigned */ 460 if(val < 0) 461 uval = (unsigned)(((-(++val)) << 1) + 1); 462 else 463 uval = (unsigned)(val << 1); 464 465 k = FLAC__bitmath_ilog2(parameter); 466 if(parameter == 1u<<k) { 467 FLAC__ASSERT(k <= 30); 468 469 msbs = uval >> k; 470 bits = 1 + k + msbs; 471 } 472 else { 473 unsigned q, r, d; 474 475 d = (1 << (k+1)) - parameter; 476 q = uval / parameter; 477 r = uval - (q * parameter); 478 479 bits = 1 + q + k; 480 if(r >= d) 481 bits++; 482 } 483 return bits; 484} 485 486unsigned FLAC__bitwriter_golomb_bits_unsigned(unsigned uval, unsigned parameter) 487{ 488 unsigned bits, msbs; 489 unsigned k; 490 491 FLAC__ASSERT(parameter > 0); 492 493 k = FLAC__bitmath_ilog2(parameter); 494 if(parameter == 1u<<k) { 495 FLAC__ASSERT(k <= 30); 496 497 msbs = uval >> k; 498 bits = 1 + k + msbs; 499 } 500 else { 501 unsigned q, r, d; 502 503 d = (1 << (k+1)) - parameter; 504 q = uval / parameter; 505 r = uval - (q * parameter); 506 507 bits = 1 + q + k; 508 if(r >= d) 509 bits++; 510 } 511 return bits; 512} 513#endif /* UNUSED */ 514 515FLAC__bool FLAC__bitwriter_write_rice_signed(FLAC__BitWriter *bw, FLAC__int32 val, unsigned parameter) 516{ 517 unsigned total_bits, interesting_bits, msbs; 518 FLAC__uint32 uval, pattern; 519 520 FLAC__ASSERT(0 != bw); 521 FLAC__ASSERT(0 != bw->buffer); 522 FLAC__ASSERT(parameter < 8*sizeof(uval)); 523 524 /* fold signed to unsigned; actual formula is: negative(v)? -2v-1 : 2v */ 525 uval = (val<<1) ^ (val>>31); 526 527 msbs = uval >> parameter; 528 interesting_bits = 1 + parameter; 529 total_bits = interesting_bits + msbs; 530 pattern = 1 << parameter; /* the unary end bit */ 531 pattern |= (uval & ((1<<parameter)-1)); /* the binary LSBs */ 532 533 if(total_bits <= 32) 534 return FLAC__bitwriter_write_raw_uint32(bw, pattern, total_bits); 535 else 536 return 537 FLAC__bitwriter_write_zeroes(bw, msbs) && /* write the unary MSBs */ 538 FLAC__bitwriter_write_raw_uint32(bw, pattern, interesting_bits); /* write the unary end bit and binary LSBs */ 539} 540 541FLAC__bool FLAC__bitwriter_write_rice_signed_block(FLAC__BitWriter *bw, const FLAC__int32 *vals, unsigned nvals, unsigned parameter) 542{ 543 const FLAC__uint32 mask1 = FLAC__WORD_ALL_ONES << parameter; /* we val|=mask1 to set the stop bit above it... */ 544 const FLAC__uint32 mask2 = FLAC__WORD_ALL_ONES >> (31-parameter); /* ...then mask off the bits above the stop bit with val&=mask2*/ 545 FLAC__uint32 uval; 546 unsigned left; 547 const unsigned lsbits = 1 + parameter; 548 unsigned msbits; 549 550 FLAC__ASSERT(0 != bw); 551 FLAC__ASSERT(0 != bw->buffer); 552 FLAC__ASSERT(parameter < 8*sizeof(bwword)-1); 553 /* WATCHOUT: code does not work with <32bit words; we can make things much faster with this assertion */ 554 FLAC__ASSERT(FLAC__BITS_PER_WORD >= 32); 555 556 while(nvals) { 557 /* fold signed to unsigned; actual formula is: negative(v)? -2v-1 : 2v */ 558 uval = (*vals<<1) ^ (*vals>>31); 559 560 msbits = uval >> parameter; 561 562#if 0 /* OPT: can remove this special case if it doesn't make up for the extra compare (doesn't make a statistically significant difference with msvc or gcc/x86) */ 563 if(bw->bits && bw->bits + msbits + lsbits <= FLAC__BITS_PER_WORD) { /* i.e. if the whole thing fits in the current bwword */ 564 /* ^^^ if bw->bits is 0 then we may have filled the buffer and have no free bwword to work in */ 565 bw->bits = bw->bits + msbits + lsbits; 566 uval |= mask1; /* set stop bit */ 567 uval &= mask2; /* mask off unused top bits */ 568 /* NOT: bw->accum <<= msbits + lsbits because msbits+lsbits could be 32, then the shift would be a NOP */ 569 bw->accum <<= msbits; 570 bw->accum <<= lsbits; 571 bw->accum |= uval; 572 if(bw->bits == FLAC__BITS_PER_WORD) { 573 bw->buffer[bw->words++] = SWAP_BE_WORD_TO_HOST(bw->accum); 574 bw->bits = 0; 575 /* burying the capacity check down here means we have to grow the buffer a little if there are more vals to do */ 576 if(bw->capacity <= bw->words && nvals > 1 && !bitwriter_grow_(bw, 1)) { 577 FLAC__ASSERT(bw->capacity == bw->words); 578 return false; 579 } 580 } 581 } 582 else { 583#elif 1 /*@@@@@@ OPT: try this version with MSVC6 to see if better, not much difference for gcc-4 */ 584 if(bw->bits && bw->bits + msbits + lsbits < FLAC__BITS_PER_WORD) { /* i.e. if the whole thing fits in the current bwword */ 585 /* ^^^ if bw->bits is 0 then we may have filled the buffer and have no free bwword to work in */ 586 bw->bits = bw->bits + msbits + lsbits; 587 uval |= mask1; /* set stop bit */ 588 uval &= mask2; /* mask off unused top bits */ 589 bw->accum <<= msbits + lsbits; 590 bw->accum |= uval; 591 } 592 else { 593#endif 594 /* slightly pessimistic size check but faster than "<= bw->words + (bw->bits+msbits+lsbits+FLAC__BITS_PER_WORD-1)/FLAC__BITS_PER_WORD" */ 595 /* OPT: pessimism may cause flurry of false calls to grow_ which eat up all savings before it */ 596 if(bw->capacity <= bw->words + bw->bits + msbits + 1/*lsbits always fit in 1 bwword*/ && !bitwriter_grow_(bw, msbits+lsbits)) 597 return false; 598 599 if(msbits) { 600 /* first part gets to word alignment */ 601 if(bw->bits) { 602 left = FLAC__BITS_PER_WORD - bw->bits; 603 if(msbits < left) { 604 bw->accum <<= msbits; 605 bw->bits += msbits; 606 goto break1; 607 } 608 else { 609 bw->accum <<= left; 610 msbits -= left; 611 bw->buffer[bw->words++] = SWAP_BE_WORD_TO_HOST(bw->accum); 612 bw->bits = 0; 613 } 614 } 615 /* do whole words */ 616 while(msbits >= FLAC__BITS_PER_WORD) { 617 bw->buffer[bw->words++] = 0; 618 msbits -= FLAC__BITS_PER_WORD; 619 } 620 /* do any leftovers */ 621 if(msbits > 0) { 622 bw->accum = 0; 623 bw->bits = msbits; 624 } 625 } 626break1: 627 uval |= mask1; /* set stop bit */ 628 uval &= mask2; /* mask off unused top bits */ 629 630 left = FLAC__BITS_PER_WORD - bw->bits; 631 if(lsbits < left) { 632 bw->accum <<= lsbits; 633 bw->accum |= uval; 634 bw->bits += lsbits; 635 } 636 else { 637 /* if bw->bits == 0, left==FLAC__BITS_PER_WORD which will always 638 * be > lsbits (because of previous assertions) so it would have 639 * triggered the (lsbits<left) case above. 640 */ 641 FLAC__ASSERT(bw->bits); 642 FLAC__ASSERT(left < FLAC__BITS_PER_WORD); 643 bw->accum <<= left; 644 bw->accum |= uval >> (bw->bits = lsbits - left); 645 bw->buffer[bw->words++] = SWAP_BE_WORD_TO_HOST(bw->accum); 646 bw->accum = uval; 647 } 648#if 1 649 } 650#endif 651 vals++; 652 nvals--; 653 } 654 return true; 655} 656 657#if 0 /* UNUSED */ 658FLAC__bool FLAC__bitwriter_write_golomb_signed(FLAC__BitWriter *bw, int val, unsigned parameter) 659{ 660 unsigned total_bits, msbs, uval; 661 unsigned k; 662 663 FLAC__ASSERT(0 != bw); 664 FLAC__ASSERT(0 != bw->buffer); 665 FLAC__ASSERT(parameter > 0); 666 667 /* fold signed to unsigned */ 668 if(val < 0) 669 uval = (unsigned)(((-(++val)) << 1) + 1); 670 else 671 uval = (unsigned)(val << 1); 672 673 k = FLAC__bitmath_ilog2(parameter); 674 if(parameter == 1u<<k) { 675 unsigned pattern; 676 677 FLAC__ASSERT(k <= 30); 678 679 msbs = uval >> k; 680 total_bits = 1 + k + msbs; 681 pattern = 1 << k; /* the unary end bit */ 682 pattern |= (uval & ((1u<<k)-1)); /* the binary LSBs */ 683 684 if(total_bits <= 32) { 685 if(!FLAC__bitwriter_write_raw_uint32(bw, pattern, total_bits)) 686 return false; 687 } 688 else { 689 /* write the unary MSBs */ 690 if(!FLAC__bitwriter_write_zeroes(bw, msbs)) 691 return false; 692 /* write the unary end bit and binary LSBs */ 693 if(!FLAC__bitwriter_write_raw_uint32(bw, pattern, k+1)) 694 return false; 695 } 696 } 697 else { 698 unsigned q, r, d; 699 700 d = (1 << (k+1)) - parameter; 701 q = uval / parameter; 702 r = uval - (q * parameter); 703 /* write the unary MSBs */ 704 if(!FLAC__bitwriter_write_zeroes(bw, q)) 705 return false; 706 /* write the unary end bit */ 707 if(!FLAC__bitwriter_write_raw_uint32(bw, 1, 1)) 708 return false; 709 /* write the binary LSBs */ 710 if(r >= d) { 711 if(!FLAC__bitwriter_write_raw_uint32(bw, r+d, k+1)) 712 return false; 713 } 714 else { 715 if(!FLAC__bitwriter_write_raw_uint32(bw, r, k)) 716 return false; 717 } 718 } 719 return true; 720} 721 722FLAC__bool FLAC__bitwriter_write_golomb_unsigned(FLAC__BitWriter *bw, unsigned uval, unsigned parameter) 723{ 724 unsigned total_bits, msbs; 725 unsigned k; 726 727 FLAC__ASSERT(0 != bw); 728 FLAC__ASSERT(0 != bw->buffer); 729 FLAC__ASSERT(parameter > 0); 730 731 k = FLAC__bitmath_ilog2(parameter); 732 if(parameter == 1u<<k) { 733 unsigned pattern; 734 735 FLAC__ASSERT(k <= 30); 736 737 msbs = uval >> k; 738 total_bits = 1 + k + msbs; 739 pattern = 1 << k; /* the unary end bit */ 740 pattern |= (uval & ((1u<<k)-1)); /* the binary LSBs */ 741 742 if(total_bits <= 32) { 743 if(!FLAC__bitwriter_write_raw_uint32(bw, pattern, total_bits)) 744 return false; 745 } 746 else { 747 /* write the unary MSBs */ 748 if(!FLAC__bitwriter_write_zeroes(bw, msbs)) 749 return false; 750 /* write the unary end bit and binary LSBs */ 751 if(!FLAC__bitwriter_write_raw_uint32(bw, pattern, k+1)) 752 return false; 753 } 754 } 755 else { 756 unsigned q, r, d; 757 758 d = (1 << (k+1)) - parameter; 759 q = uval / parameter; 760 r = uval - (q * parameter); 761 /* write the unary MSBs */ 762 if(!FLAC__bitwriter_write_zeroes(bw, q)) 763 return false; 764 /* write the unary end bit */ 765 if(!FLAC__bitwriter_write_raw_uint32(bw, 1, 1)) 766 return false; 767 /* write the binary LSBs */ 768 if(r >= d) { 769 if(!FLAC__bitwriter_write_raw_uint32(bw, r+d, k+1)) 770 return false; 771 } 772 else { 773 if(!FLAC__bitwriter_write_raw_uint32(bw, r, k)) 774 return false; 775 } 776 } 777 return true; 778} 779#endif /* UNUSED */ 780 781FLAC__bool FLAC__bitwriter_write_utf8_uint32(FLAC__BitWriter *bw, FLAC__uint32 val) 782{ 783 FLAC__bool ok = 1; 784 785 FLAC__ASSERT(0 != bw); 786 FLAC__ASSERT(0 != bw->buffer); 787 788 FLAC__ASSERT(!(val & 0x80000000)); /* this version only handles 31 bits */ 789 790 if(val < 0x80) { 791 return FLAC__bitwriter_write_raw_uint32(bw, val, 8); 792 } 793 else if(val < 0x800) { 794 ok &= FLAC__bitwriter_write_raw_uint32(bw, 0xC0 | (val>>6), 8); 795 ok &= FLAC__bitwriter_write_raw_uint32(bw, 0x80 | (val&0x3F), 8); 796 } 797 else if(val < 0x10000) { 798 ok &= FLAC__bitwriter_write_raw_uint32(bw, 0xE0 | (val>>12), 8); 799 ok &= FLAC__bitwriter_write_raw_uint32(bw, 0x80 | ((val>>6)&0x3F), 8); 800 ok &= FLAC__bitwriter_write_raw_uint32(bw, 0x80 | (val&0x3F), 8); 801 } 802 else if(val < 0x200000) { 803 ok &= FLAC__bitwriter_write_raw_uint32(bw, 0xF0 | (val>>18), 8); 804 ok &= FLAC__bitwriter_write_raw_uint32(bw, 0x80 | ((val>>12)&0x3F), 8); 805 ok &= FLAC__bitwriter_write_raw_uint32(bw, 0x80 | ((val>>6)&0x3F), 8); 806 ok &= FLAC__bitwriter_write_raw_uint32(bw, 0x80 | (val&0x3F), 8); 807 } 808 else if(val < 0x4000000) { 809 ok &= FLAC__bitwriter_write_raw_uint32(bw, 0xF8 | (val>>24), 8); 810 ok &= FLAC__bitwriter_write_raw_uint32(bw, 0x80 | ((val>>18)&0x3F), 8); 811 ok &= FLAC__bitwriter_write_raw_uint32(bw, 0x80 | ((val>>12)&0x3F), 8); 812 ok &= FLAC__bitwriter_write_raw_uint32(bw, 0x80 | ((val>>6)&0x3F), 8); 813 ok &= FLAC__bitwriter_write_raw_uint32(bw, 0x80 | (val&0x3F), 8); 814 } 815 else { 816 ok &= FLAC__bitwriter_write_raw_uint32(bw, 0xFC | (val>>30), 8); 817 ok &= FLAC__bitwriter_write_raw_uint32(bw, 0x80 | ((val>>24)&0x3F), 8); 818 ok &= FLAC__bitwriter_write_raw_uint32(bw, 0x80 | ((val>>18)&0x3F), 8); 819 ok &= FLAC__bitwriter_write_raw_uint32(bw, 0x80 | ((val>>12)&0x3F), 8); 820 ok &= FLAC__bitwriter_write_raw_uint32(bw, 0x80 | ((val>>6)&0x3F), 8); 821 ok &= FLAC__bitwriter_write_raw_uint32(bw, 0x80 | (val&0x3F), 8); 822 } 823 824 return ok; 825} 826 827FLAC__bool FLAC__bitwriter_write_utf8_uint64(FLAC__BitWriter *bw, FLAC__uint64 val) 828{ 829 FLAC__bool ok = 1; 830 831 FLAC__ASSERT(0 != bw); 832 FLAC__ASSERT(0 != bw->buffer); 833 834 FLAC__ASSERT(!(val & FLAC__U64L(0xFFFFFFF000000000))); /* this version only handles 36 bits */ 835 836 if(val < 0x80) { 837 return FLAC__bitwriter_write_raw_uint32(bw, (FLAC__uint32)val, 8); 838 } 839 else if(val < 0x800) { 840 ok &= FLAC__bitwriter_write_raw_uint32(bw, 0xC0 | (FLAC__uint32)(val>>6), 8); 841 ok &= FLAC__bitwriter_write_raw_uint32(bw, 0x80 | (FLAC__uint32)(val&0x3F), 8); 842 } 843 else if(val < 0x10000) { 844 ok &= FLAC__bitwriter_write_raw_uint32(bw, 0xE0 | (FLAC__uint32)(val>>12), 8); 845 ok &= FLAC__bitwriter_write_raw_uint32(bw, 0x80 | (FLAC__uint32)((val>>6)&0x3F), 8); 846 ok &= FLAC__bitwriter_write_raw_uint32(bw, 0x80 | (FLAC__uint32)(val&0x3F), 8); 847 } 848 else if(val < 0x200000) { 849 ok &= FLAC__bitwriter_write_raw_uint32(bw, 0xF0 | (FLAC__uint32)(val>>18), 8); 850 ok &= FLAC__bitwriter_write_raw_uint32(bw, 0x80 | (FLAC__uint32)((val>>12)&0x3F), 8); 851 ok &= FLAC__bitwriter_write_raw_uint32(bw, 0x80 | (FLAC__uint32)((val>>6)&0x3F), 8); 852 ok &= FLAC__bitwriter_write_raw_uint32(bw, 0x80 | (FLAC__uint32)(val&0x3F), 8); 853 } 854 else if(val < 0x4000000) { 855 ok &= FLAC__bitwriter_write_raw_uint32(bw, 0xF8 | (FLAC__uint32)(val>>24), 8); 856 ok &= FLAC__bitwriter_write_raw_uint32(bw, 0x80 | (FLAC__uint32)((val>>18)&0x3F), 8); 857 ok &= FLAC__bitwriter_write_raw_uint32(bw, 0x80 | (FLAC__uint32)((val>>12)&0x3F), 8); 858 ok &= FLAC__bitwriter_write_raw_uint32(bw, 0x80 | (FLAC__uint32)((val>>6)&0x3F), 8); 859 ok &= FLAC__bitwriter_write_raw_uint32(bw, 0x80 | (FLAC__uint32)(val&0x3F), 8); 860 } 861 else if(val < 0x80000000) { 862 ok &= FLAC__bitwriter_write_raw_uint32(bw, 0xFC | (FLAC__uint32)(val>>30), 8); 863 ok &= FLAC__bitwriter_write_raw_uint32(bw, 0x80 | (FLAC__uint32)((val>>24)&0x3F), 8); 864 ok &= FLAC__bitwriter_write_raw_uint32(bw, 0x80 | (FLAC__uint32)((val>>18)&0x3F), 8); 865 ok &= FLAC__bitwriter_write_raw_uint32(bw, 0x80 | (FLAC__uint32)((val>>12)&0x3F), 8); 866 ok &= FLAC__bitwriter_write_raw_uint32(bw, 0x80 | (FLAC__uint32)((val>>6)&0x3F), 8); 867 ok &= FLAC__bitwriter_write_raw_uint32(bw, 0x80 | (FLAC__uint32)(val&0x3F), 8); 868 } 869 else { 870 ok &= FLAC__bitwriter_write_raw_uint32(bw, 0xFE, 8); 871 ok &= FLAC__bitwriter_write_raw_uint32(bw, 0x80 | (FLAC__uint32)((val>>30)&0x3F), 8); 872 ok &= FLAC__bitwriter_write_raw_uint32(bw, 0x80 | (FLAC__uint32)((val>>24)&0x3F), 8); 873 ok &= FLAC__bitwriter_write_raw_uint32(bw, 0x80 | (FLAC__uint32)((val>>18)&0x3F), 8); 874 ok &= FLAC__bitwriter_write_raw_uint32(bw, 0x80 | (FLAC__uint32)((val>>12)&0x3F), 8); 875 ok &= FLAC__bitwriter_write_raw_uint32(bw, 0x80 | (FLAC__uint32)((val>>6)&0x3F), 8); 876 ok &= FLAC__bitwriter_write_raw_uint32(bw, 0x80 | (FLAC__uint32)(val&0x3F), 8); 877 } 878 879 return ok; 880} 881 882FLAC__bool FLAC__bitwriter_zero_pad_to_byte_boundary(FLAC__BitWriter *bw) 883{ 884 /* 0-pad to byte boundary */ 885 if(bw->bits & 7u) 886 return FLAC__bitwriter_write_zeroes(bw, 8 - (bw->bits & 7u)); 887 else 888 return true; 889} 890