bashi@chromium.org | c2a9375 | 2012-05-02 00:18:22 +0000 | [diff] [blame^] | 1 | /* LzmaDec.c -- LZMA Decoder |
| 2 | 2009-09-20 : Igor Pavlov : Public domain */ |
| 3 | |
| 4 | #include "LzmaDec.h" |
| 5 | |
| 6 | #include <string.h> |
| 7 | |
| 8 | #define kNumTopBits 24 |
| 9 | #define kTopValue ((UInt32)1 << kNumTopBits) |
| 10 | |
| 11 | #define kNumBitModelTotalBits 11 |
| 12 | #define kBitModelTotal (1 << kNumBitModelTotalBits) |
| 13 | #define kNumMoveBits 5 |
| 14 | |
| 15 | #define RC_INIT_SIZE 5 |
| 16 | |
| 17 | #define NORMALIZE if (range < kTopValue) { range <<= 8; code = (code << 8) | (*buf++); } |
| 18 | |
| 19 | #define IF_BIT_0(p) ttt = *(p); NORMALIZE; bound = (range >> kNumBitModelTotalBits) * ttt; if (code < bound) |
| 20 | #define UPDATE_0(p) range = bound; *(p) = (CLzmaProb)(ttt + ((kBitModelTotal - ttt) >> kNumMoveBits)); |
| 21 | #define UPDATE_1(p) range -= bound; code -= bound; *(p) = (CLzmaProb)(ttt - (ttt >> kNumMoveBits)); |
| 22 | #define GET_BIT2(p, i, A0, A1) IF_BIT_0(p) \ |
| 23 | { UPDATE_0(p); i = (i + i); A0; } else \ |
| 24 | { UPDATE_1(p); i = (i + i) + 1; A1; } |
| 25 | #define GET_BIT(p, i) GET_BIT2(p, i, ; , ;) |
| 26 | |
| 27 | #define TREE_GET_BIT(probs, i) { GET_BIT((probs + i), i); } |
| 28 | #define TREE_DECODE(probs, limit, i) \ |
| 29 | { i = 1; do { TREE_GET_BIT(probs, i); } while (i < limit); i -= limit; } |
| 30 | |
| 31 | /* #define _LZMA_SIZE_OPT */ |
| 32 | |
| 33 | #ifdef _LZMA_SIZE_OPT |
| 34 | #define TREE_6_DECODE(probs, i) TREE_DECODE(probs, (1 << 6), i) |
| 35 | #else |
| 36 | #define TREE_6_DECODE(probs, i) \ |
| 37 | { i = 1; \ |
| 38 | TREE_GET_BIT(probs, i); \ |
| 39 | TREE_GET_BIT(probs, i); \ |
| 40 | TREE_GET_BIT(probs, i); \ |
| 41 | TREE_GET_BIT(probs, i); \ |
| 42 | TREE_GET_BIT(probs, i); \ |
| 43 | TREE_GET_BIT(probs, i); \ |
| 44 | i -= 0x40; } |
| 45 | #endif |
| 46 | |
| 47 | #define NORMALIZE_CHECK if (range < kTopValue) { if (buf >= bufLimit) return DUMMY_ERROR; range <<= 8; code = (code << 8) | (*buf++); } |
| 48 | |
| 49 | #define IF_BIT_0_CHECK(p) ttt = *(p); NORMALIZE_CHECK; bound = (range >> kNumBitModelTotalBits) * ttt; if (code < bound) |
| 50 | #define UPDATE_0_CHECK range = bound; |
| 51 | #define UPDATE_1_CHECK range -= bound; code -= bound; |
| 52 | #define GET_BIT2_CHECK(p, i, A0, A1) IF_BIT_0_CHECK(p) \ |
| 53 | { UPDATE_0_CHECK; i = (i + i); A0; } else \ |
| 54 | { UPDATE_1_CHECK; i = (i + i) + 1; A1; } |
| 55 | #define GET_BIT_CHECK(p, i) GET_BIT2_CHECK(p, i, ; , ;) |
| 56 | #define TREE_DECODE_CHECK(probs, limit, i) \ |
| 57 | { i = 1; do { GET_BIT_CHECK(probs + i, i) } while (i < limit); i -= limit; } |
| 58 | |
| 59 | |
| 60 | #define kNumPosBitsMax 4 |
| 61 | #define kNumPosStatesMax (1 << kNumPosBitsMax) |
| 62 | |
| 63 | #define kLenNumLowBits 3 |
| 64 | #define kLenNumLowSymbols (1 << kLenNumLowBits) |
| 65 | #define kLenNumMidBits 3 |
| 66 | #define kLenNumMidSymbols (1 << kLenNumMidBits) |
| 67 | #define kLenNumHighBits 8 |
| 68 | #define kLenNumHighSymbols (1 << kLenNumHighBits) |
| 69 | |
| 70 | #define LenChoice 0 |
| 71 | #define LenChoice2 (LenChoice + 1) |
| 72 | #define LenLow (LenChoice2 + 1) |
| 73 | #define LenMid (LenLow + (kNumPosStatesMax << kLenNumLowBits)) |
| 74 | #define LenHigh (LenMid + (kNumPosStatesMax << kLenNumMidBits)) |
| 75 | #define kNumLenProbs (LenHigh + kLenNumHighSymbols) |
| 76 | |
| 77 | |
| 78 | #define kNumStates 12 |
| 79 | #define kNumLitStates 7 |
| 80 | |
| 81 | #define kStartPosModelIndex 4 |
| 82 | #define kEndPosModelIndex 14 |
| 83 | #define kNumFullDistances (1 << (kEndPosModelIndex >> 1)) |
| 84 | |
| 85 | #define kNumPosSlotBits 6 |
| 86 | #define kNumLenToPosStates 4 |
| 87 | |
| 88 | #define kNumAlignBits 4 |
| 89 | #define kAlignTableSize (1 << kNumAlignBits) |
| 90 | |
| 91 | #define kMatchMinLen 2 |
| 92 | #define kMatchSpecLenStart (kMatchMinLen + kLenNumLowSymbols + kLenNumMidSymbols + kLenNumHighSymbols) |
| 93 | |
| 94 | #define IsMatch 0 |
| 95 | #define IsRep (IsMatch + (kNumStates << kNumPosBitsMax)) |
| 96 | #define IsRepG0 (IsRep + kNumStates) |
| 97 | #define IsRepG1 (IsRepG0 + kNumStates) |
| 98 | #define IsRepG2 (IsRepG1 + kNumStates) |
| 99 | #define IsRep0Long (IsRepG2 + kNumStates) |
| 100 | #define PosSlot (IsRep0Long + (kNumStates << kNumPosBitsMax)) |
| 101 | #define SpecPos (PosSlot + (kNumLenToPosStates << kNumPosSlotBits)) |
| 102 | #define Align (SpecPos + kNumFullDistances - kEndPosModelIndex) |
| 103 | #define LenCoder (Align + kAlignTableSize) |
| 104 | #define RepLenCoder (LenCoder + kNumLenProbs) |
| 105 | #define Literal (RepLenCoder + kNumLenProbs) |
| 106 | |
| 107 | #define LZMA_BASE_SIZE 1846 |
| 108 | #define LZMA_LIT_SIZE 768 |
| 109 | |
| 110 | #define LzmaProps_GetNumProbs(p) ((UInt32)LZMA_BASE_SIZE + (LZMA_LIT_SIZE << ((p)->lc + (p)->lp))) |
| 111 | |
| 112 | #if Literal != LZMA_BASE_SIZE |
| 113 | StopCompilingDueBUG |
| 114 | #endif |
| 115 | |
| 116 | #define LZMA_DIC_MIN (1 << 12) |
| 117 | |
| 118 | /* First LZMA-symbol is always decoded. |
| 119 | And it decodes new LZMA-symbols while (buf < bufLimit), but "buf" is without last normalization |
| 120 | Out: |
| 121 | Result: |
| 122 | SZ_OK - OK |
| 123 | SZ_ERROR_DATA - Error |
| 124 | p->remainLen: |
| 125 | < kMatchSpecLenStart : normal remain |
| 126 | = kMatchSpecLenStart : finished |
| 127 | = kMatchSpecLenStart + 1 : Flush marker |
| 128 | = kMatchSpecLenStart + 2 : State Init Marker |
| 129 | */ |
| 130 | |
| 131 | static int MY_FAST_CALL LzmaDec_DecodeReal(CLzmaDec *p, SizeT limit, const Byte *bufLimit) |
| 132 | { |
| 133 | CLzmaProb *probs = p->probs; |
| 134 | |
| 135 | unsigned state = p->state; |
| 136 | UInt32 rep0 = p->reps[0], rep1 = p->reps[1], rep2 = p->reps[2], rep3 = p->reps[3]; |
| 137 | unsigned pbMask = ((unsigned)1 << (p->prop.pb)) - 1; |
| 138 | unsigned lpMask = ((unsigned)1 << (p->prop.lp)) - 1; |
| 139 | unsigned lc = p->prop.lc; |
| 140 | |
| 141 | Byte *dic = p->dic; |
| 142 | SizeT dicBufSize = p->dicBufSize; |
| 143 | SizeT dicPos = p->dicPos; |
| 144 | |
| 145 | UInt32 processedPos = p->processedPos; |
| 146 | UInt32 checkDicSize = p->checkDicSize; |
| 147 | unsigned len = 0; |
| 148 | |
| 149 | const Byte *buf = p->buf; |
| 150 | UInt32 range = p->range; |
| 151 | UInt32 code = p->code; |
| 152 | |
| 153 | do |
| 154 | { |
| 155 | CLzmaProb *prob; |
| 156 | UInt32 bound; |
| 157 | unsigned ttt; |
| 158 | unsigned posState = processedPos & pbMask; |
| 159 | |
| 160 | prob = probs + IsMatch + (state << kNumPosBitsMax) + posState; |
| 161 | IF_BIT_0(prob) |
| 162 | { |
| 163 | unsigned symbol; |
| 164 | UPDATE_0(prob); |
| 165 | prob = probs + Literal; |
| 166 | if (checkDicSize != 0 || processedPos != 0) |
| 167 | prob += (LZMA_LIT_SIZE * (((processedPos & lpMask) << lc) + |
| 168 | (dic[(dicPos == 0 ? dicBufSize : dicPos) - 1] >> (8 - lc)))); |
| 169 | |
| 170 | if (state < kNumLitStates) |
| 171 | { |
| 172 | state -= (state < 4) ? state : 3; |
| 173 | symbol = 1; |
| 174 | do { GET_BIT(prob + symbol, symbol) } while (symbol < 0x100); |
| 175 | } |
| 176 | else |
| 177 | { |
| 178 | unsigned matchByte = p->dic[(dicPos - rep0) + ((dicPos < rep0) ? dicBufSize : 0)]; |
| 179 | unsigned offs = 0x100; |
| 180 | state -= (state < 10) ? 3 : 6; |
| 181 | symbol = 1; |
| 182 | do |
| 183 | { |
| 184 | unsigned bit; |
| 185 | CLzmaProb *probLit; |
| 186 | matchByte <<= 1; |
| 187 | bit = (matchByte & offs); |
| 188 | probLit = prob + offs + bit + symbol; |
| 189 | GET_BIT2(probLit, symbol, offs &= ~bit, offs &= bit) |
| 190 | } |
| 191 | while (symbol < 0x100); |
| 192 | } |
| 193 | dic[dicPos++] = (Byte)symbol; |
| 194 | processedPos++; |
| 195 | continue; |
| 196 | } |
| 197 | else |
| 198 | { |
| 199 | UPDATE_1(prob); |
| 200 | prob = probs + IsRep + state; |
| 201 | IF_BIT_0(prob) |
| 202 | { |
| 203 | UPDATE_0(prob); |
| 204 | state += kNumStates; |
| 205 | prob = probs + LenCoder; |
| 206 | } |
| 207 | else |
| 208 | { |
| 209 | UPDATE_1(prob); |
| 210 | if (checkDicSize == 0 && processedPos == 0) |
| 211 | return SZ_ERROR_DATA; |
| 212 | prob = probs + IsRepG0 + state; |
| 213 | IF_BIT_0(prob) |
| 214 | { |
| 215 | UPDATE_0(prob); |
| 216 | prob = probs + IsRep0Long + (state << kNumPosBitsMax) + posState; |
| 217 | IF_BIT_0(prob) |
| 218 | { |
| 219 | UPDATE_0(prob); |
| 220 | dic[dicPos] = dic[(dicPos - rep0) + ((dicPos < rep0) ? dicBufSize : 0)]; |
| 221 | dicPos++; |
| 222 | processedPos++; |
| 223 | state = state < kNumLitStates ? 9 : 11; |
| 224 | continue; |
| 225 | } |
| 226 | UPDATE_1(prob); |
| 227 | } |
| 228 | else |
| 229 | { |
| 230 | UInt32 distance; |
| 231 | UPDATE_1(prob); |
| 232 | prob = probs + IsRepG1 + state; |
| 233 | IF_BIT_0(prob) |
| 234 | { |
| 235 | UPDATE_0(prob); |
| 236 | distance = rep1; |
| 237 | } |
| 238 | else |
| 239 | { |
| 240 | UPDATE_1(prob); |
| 241 | prob = probs + IsRepG2 + state; |
| 242 | IF_BIT_0(prob) |
| 243 | { |
| 244 | UPDATE_0(prob); |
| 245 | distance = rep2; |
| 246 | } |
| 247 | else |
| 248 | { |
| 249 | UPDATE_1(prob); |
| 250 | distance = rep3; |
| 251 | rep3 = rep2; |
| 252 | } |
| 253 | rep2 = rep1; |
| 254 | } |
| 255 | rep1 = rep0; |
| 256 | rep0 = distance; |
| 257 | } |
| 258 | state = state < kNumLitStates ? 8 : 11; |
| 259 | prob = probs + RepLenCoder; |
| 260 | } |
| 261 | { |
| 262 | unsigned limit, offset; |
| 263 | CLzmaProb *probLen = prob + LenChoice; |
| 264 | IF_BIT_0(probLen) |
| 265 | { |
| 266 | UPDATE_0(probLen); |
| 267 | probLen = prob + LenLow + (posState << kLenNumLowBits); |
| 268 | offset = 0; |
| 269 | limit = (1 << kLenNumLowBits); |
| 270 | } |
| 271 | else |
| 272 | { |
| 273 | UPDATE_1(probLen); |
| 274 | probLen = prob + LenChoice2; |
| 275 | IF_BIT_0(probLen) |
| 276 | { |
| 277 | UPDATE_0(probLen); |
| 278 | probLen = prob + LenMid + (posState << kLenNumMidBits); |
| 279 | offset = kLenNumLowSymbols; |
| 280 | limit = (1 << kLenNumMidBits); |
| 281 | } |
| 282 | else |
| 283 | { |
| 284 | UPDATE_1(probLen); |
| 285 | probLen = prob + LenHigh; |
| 286 | offset = kLenNumLowSymbols + kLenNumMidSymbols; |
| 287 | limit = (1 << kLenNumHighBits); |
| 288 | } |
| 289 | } |
| 290 | TREE_DECODE(probLen, limit, len); |
| 291 | len += offset; |
| 292 | } |
| 293 | |
| 294 | if (state >= kNumStates) |
| 295 | { |
| 296 | UInt32 distance; |
| 297 | prob = probs + PosSlot + |
| 298 | ((len < kNumLenToPosStates ? len : kNumLenToPosStates - 1) << kNumPosSlotBits); |
| 299 | TREE_6_DECODE(prob, distance); |
| 300 | if (distance >= kStartPosModelIndex) |
| 301 | { |
| 302 | unsigned posSlot = (unsigned)distance; |
| 303 | int numDirectBits = (int)(((distance >> 1) - 1)); |
| 304 | distance = (2 | (distance & 1)); |
| 305 | if (posSlot < kEndPosModelIndex) |
| 306 | { |
| 307 | distance <<= numDirectBits; |
| 308 | prob = probs + SpecPos + distance - posSlot - 1; |
| 309 | { |
| 310 | UInt32 mask = 1; |
| 311 | unsigned i = 1; |
| 312 | do |
| 313 | { |
| 314 | GET_BIT2(prob + i, i, ; , distance |= mask); |
| 315 | mask <<= 1; |
| 316 | } |
| 317 | while (--numDirectBits != 0); |
| 318 | } |
| 319 | } |
| 320 | else |
| 321 | { |
| 322 | numDirectBits -= kNumAlignBits; |
| 323 | do |
| 324 | { |
| 325 | NORMALIZE |
| 326 | range >>= 1; |
| 327 | |
| 328 | { |
| 329 | UInt32 t; |
| 330 | code -= range; |
| 331 | t = (0 - ((UInt32)code >> 31)); /* (UInt32)((Int32)code >> 31) */ |
| 332 | distance = (distance << 1) + (t + 1); |
| 333 | code += range & t; |
| 334 | } |
| 335 | /* |
| 336 | distance <<= 1; |
| 337 | if (code >= range) |
| 338 | { |
| 339 | code -= range; |
| 340 | distance |= 1; |
| 341 | } |
| 342 | */ |
| 343 | } |
| 344 | while (--numDirectBits != 0); |
| 345 | prob = probs + Align; |
| 346 | distance <<= kNumAlignBits; |
| 347 | { |
| 348 | unsigned i = 1; |
| 349 | GET_BIT2(prob + i, i, ; , distance |= 1); |
| 350 | GET_BIT2(prob + i, i, ; , distance |= 2); |
| 351 | GET_BIT2(prob + i, i, ; , distance |= 4); |
| 352 | GET_BIT2(prob + i, i, ; , distance |= 8); |
| 353 | } |
| 354 | if (distance == (UInt32)0xFFFFFFFF) |
| 355 | { |
| 356 | len += kMatchSpecLenStart; |
| 357 | state -= kNumStates; |
| 358 | break; |
| 359 | } |
| 360 | } |
| 361 | } |
| 362 | rep3 = rep2; |
| 363 | rep2 = rep1; |
| 364 | rep1 = rep0; |
| 365 | rep0 = distance + 1; |
| 366 | if (checkDicSize == 0) |
| 367 | { |
| 368 | if (distance >= processedPos) |
| 369 | return SZ_ERROR_DATA; |
| 370 | } |
| 371 | else if (distance >= checkDicSize) |
| 372 | return SZ_ERROR_DATA; |
| 373 | state = (state < kNumStates + kNumLitStates) ? kNumLitStates : kNumLitStates + 3; |
| 374 | } |
| 375 | |
| 376 | len += kMatchMinLen; |
| 377 | |
| 378 | if (limit == dicPos) |
| 379 | return SZ_ERROR_DATA; |
| 380 | { |
| 381 | SizeT rem = limit - dicPos; |
| 382 | unsigned curLen = ((rem < len) ? (unsigned)rem : len); |
| 383 | SizeT pos = (dicPos - rep0) + ((dicPos < rep0) ? dicBufSize : 0); |
| 384 | |
| 385 | processedPos += curLen; |
| 386 | |
| 387 | len -= curLen; |
| 388 | if (pos + curLen <= dicBufSize) |
| 389 | { |
| 390 | Byte *dest = dic + dicPos; |
| 391 | ptrdiff_t src = (ptrdiff_t)pos - (ptrdiff_t)dicPos; |
| 392 | const Byte *lim = dest + curLen; |
| 393 | dicPos += curLen; |
| 394 | do |
| 395 | *(dest) = (Byte)*(dest + src); |
| 396 | while (++dest != lim); |
| 397 | } |
| 398 | else |
| 399 | { |
| 400 | do |
| 401 | { |
| 402 | dic[dicPos++] = dic[pos]; |
| 403 | if (++pos == dicBufSize) |
| 404 | pos = 0; |
| 405 | } |
| 406 | while (--curLen != 0); |
| 407 | } |
| 408 | } |
| 409 | } |
| 410 | } |
| 411 | while (dicPos < limit && buf < bufLimit); |
| 412 | NORMALIZE; |
| 413 | p->buf = buf; |
| 414 | p->range = range; |
| 415 | p->code = code; |
| 416 | p->remainLen = len; |
| 417 | p->dicPos = dicPos; |
| 418 | p->processedPos = processedPos; |
| 419 | p->reps[0] = rep0; |
| 420 | p->reps[1] = rep1; |
| 421 | p->reps[2] = rep2; |
| 422 | p->reps[3] = rep3; |
| 423 | p->state = state; |
| 424 | |
| 425 | return SZ_OK; |
| 426 | } |
| 427 | |
| 428 | static void MY_FAST_CALL LzmaDec_WriteRem(CLzmaDec *p, SizeT limit) |
| 429 | { |
| 430 | if (p->remainLen != 0 && p->remainLen < kMatchSpecLenStart) |
| 431 | { |
| 432 | Byte *dic = p->dic; |
| 433 | SizeT dicPos = p->dicPos; |
| 434 | SizeT dicBufSize = p->dicBufSize; |
| 435 | unsigned len = p->remainLen; |
| 436 | UInt32 rep0 = p->reps[0]; |
| 437 | if (limit - dicPos < len) |
| 438 | len = (unsigned)(limit - dicPos); |
| 439 | |
| 440 | if (p->checkDicSize == 0 && p->prop.dicSize - p->processedPos <= len) |
| 441 | p->checkDicSize = p->prop.dicSize; |
| 442 | |
| 443 | p->processedPos += len; |
| 444 | p->remainLen -= len; |
| 445 | while (len-- != 0) |
| 446 | { |
| 447 | dic[dicPos] = dic[(dicPos - rep0) + ((dicPos < rep0) ? dicBufSize : 0)]; |
| 448 | dicPos++; |
| 449 | } |
| 450 | p->dicPos = dicPos; |
| 451 | } |
| 452 | } |
| 453 | |
| 454 | static int MY_FAST_CALL LzmaDec_DecodeReal2(CLzmaDec *p, SizeT limit, const Byte *bufLimit) |
| 455 | { |
| 456 | do |
| 457 | { |
| 458 | SizeT limit2 = limit; |
| 459 | if (p->checkDicSize == 0) |
| 460 | { |
| 461 | UInt32 rem = p->prop.dicSize - p->processedPos; |
| 462 | if (limit - p->dicPos > rem) |
| 463 | limit2 = p->dicPos + rem; |
| 464 | } |
| 465 | RINOK(LzmaDec_DecodeReal(p, limit2, bufLimit)); |
| 466 | if (p->processedPos >= p->prop.dicSize) |
| 467 | p->checkDicSize = p->prop.dicSize; |
| 468 | LzmaDec_WriteRem(p, limit); |
| 469 | } |
| 470 | while (p->dicPos < limit && p->buf < bufLimit && p->remainLen < kMatchSpecLenStart); |
| 471 | |
| 472 | if (p->remainLen > kMatchSpecLenStart) |
| 473 | { |
| 474 | p->remainLen = kMatchSpecLenStart; |
| 475 | } |
| 476 | return 0; |
| 477 | } |
| 478 | |
| 479 | typedef enum |
| 480 | { |
| 481 | DUMMY_ERROR, /* unexpected end of input stream */ |
| 482 | DUMMY_LIT, |
| 483 | DUMMY_MATCH, |
| 484 | DUMMY_REP |
| 485 | } ELzmaDummy; |
| 486 | |
| 487 | static ELzmaDummy LzmaDec_TryDummy(const CLzmaDec *p, const Byte *buf, SizeT inSize) |
| 488 | { |
| 489 | UInt32 range = p->range; |
| 490 | UInt32 code = p->code; |
| 491 | const Byte *bufLimit = buf + inSize; |
| 492 | CLzmaProb *probs = p->probs; |
| 493 | unsigned state = p->state; |
| 494 | ELzmaDummy res; |
| 495 | |
| 496 | { |
| 497 | CLzmaProb *prob; |
| 498 | UInt32 bound; |
| 499 | unsigned ttt; |
| 500 | unsigned posState = (p->processedPos) & ((1 << p->prop.pb) - 1); |
| 501 | |
| 502 | prob = probs + IsMatch + (state << kNumPosBitsMax) + posState; |
| 503 | IF_BIT_0_CHECK(prob) |
| 504 | { |
| 505 | UPDATE_0_CHECK |
| 506 | |
| 507 | /* if (bufLimit - buf >= 7) return DUMMY_LIT; */ |
| 508 | |
| 509 | prob = probs + Literal; |
| 510 | if (p->checkDicSize != 0 || p->processedPos != 0) |
| 511 | prob += (LZMA_LIT_SIZE * |
| 512 | ((((p->processedPos) & ((1 << (p->prop.lp)) - 1)) << p->prop.lc) + |
| 513 | (p->dic[(p->dicPos == 0 ? p->dicBufSize : p->dicPos) - 1] >> (8 - p->prop.lc)))); |
| 514 | |
| 515 | if (state < kNumLitStates) |
| 516 | { |
| 517 | unsigned symbol = 1; |
| 518 | do { GET_BIT_CHECK(prob + symbol, symbol) } while (symbol < 0x100); |
| 519 | } |
| 520 | else |
| 521 | { |
| 522 | unsigned matchByte = p->dic[p->dicPos - p->reps[0] + |
| 523 | ((p->dicPos < p->reps[0]) ? p->dicBufSize : 0)]; |
| 524 | unsigned offs = 0x100; |
| 525 | unsigned symbol = 1; |
| 526 | do |
| 527 | { |
| 528 | unsigned bit; |
| 529 | CLzmaProb *probLit; |
| 530 | matchByte <<= 1; |
| 531 | bit = (matchByte & offs); |
| 532 | probLit = prob + offs + bit + symbol; |
| 533 | GET_BIT2_CHECK(probLit, symbol, offs &= ~bit, offs &= bit) |
| 534 | } |
| 535 | while (symbol < 0x100); |
| 536 | } |
| 537 | res = DUMMY_LIT; |
| 538 | } |
| 539 | else |
| 540 | { |
| 541 | unsigned len; |
| 542 | UPDATE_1_CHECK; |
| 543 | |
| 544 | prob = probs + IsRep + state; |
| 545 | IF_BIT_0_CHECK(prob) |
| 546 | { |
| 547 | UPDATE_0_CHECK; |
| 548 | state = 0; |
| 549 | prob = probs + LenCoder; |
| 550 | res = DUMMY_MATCH; |
| 551 | } |
| 552 | else |
| 553 | { |
| 554 | UPDATE_1_CHECK; |
| 555 | res = DUMMY_REP; |
| 556 | prob = probs + IsRepG0 + state; |
| 557 | IF_BIT_0_CHECK(prob) |
| 558 | { |
| 559 | UPDATE_0_CHECK; |
| 560 | prob = probs + IsRep0Long + (state << kNumPosBitsMax) + posState; |
| 561 | IF_BIT_0_CHECK(prob) |
| 562 | { |
| 563 | UPDATE_0_CHECK; |
| 564 | NORMALIZE_CHECK; |
| 565 | return DUMMY_REP; |
| 566 | } |
| 567 | else |
| 568 | { |
| 569 | UPDATE_1_CHECK; |
| 570 | } |
| 571 | } |
| 572 | else |
| 573 | { |
| 574 | UPDATE_1_CHECK; |
| 575 | prob = probs + IsRepG1 + state; |
| 576 | IF_BIT_0_CHECK(prob) |
| 577 | { |
| 578 | UPDATE_0_CHECK; |
| 579 | } |
| 580 | else |
| 581 | { |
| 582 | UPDATE_1_CHECK; |
| 583 | prob = probs + IsRepG2 + state; |
| 584 | IF_BIT_0_CHECK(prob) |
| 585 | { |
| 586 | UPDATE_0_CHECK; |
| 587 | } |
| 588 | else |
| 589 | { |
| 590 | UPDATE_1_CHECK; |
| 591 | } |
| 592 | } |
| 593 | } |
| 594 | state = kNumStates; |
| 595 | prob = probs + RepLenCoder; |
| 596 | } |
| 597 | { |
| 598 | unsigned limit, offset; |
| 599 | CLzmaProb *probLen = prob + LenChoice; |
| 600 | IF_BIT_0_CHECK(probLen) |
| 601 | { |
| 602 | UPDATE_0_CHECK; |
| 603 | probLen = prob + LenLow + (posState << kLenNumLowBits); |
| 604 | offset = 0; |
| 605 | limit = 1 << kLenNumLowBits; |
| 606 | } |
| 607 | else |
| 608 | { |
| 609 | UPDATE_1_CHECK; |
| 610 | probLen = prob + LenChoice2; |
| 611 | IF_BIT_0_CHECK(probLen) |
| 612 | { |
| 613 | UPDATE_0_CHECK; |
| 614 | probLen = prob + LenMid + (posState << kLenNumMidBits); |
| 615 | offset = kLenNumLowSymbols; |
| 616 | limit = 1 << kLenNumMidBits; |
| 617 | } |
| 618 | else |
| 619 | { |
| 620 | UPDATE_1_CHECK; |
| 621 | probLen = prob + LenHigh; |
| 622 | offset = kLenNumLowSymbols + kLenNumMidSymbols; |
| 623 | limit = 1 << kLenNumHighBits; |
| 624 | } |
| 625 | } |
| 626 | TREE_DECODE_CHECK(probLen, limit, len); |
| 627 | len += offset; |
| 628 | } |
| 629 | |
| 630 | if (state < 4) |
| 631 | { |
| 632 | unsigned posSlot; |
| 633 | prob = probs + PosSlot + |
| 634 | ((len < kNumLenToPosStates ? len : kNumLenToPosStates - 1) << |
| 635 | kNumPosSlotBits); |
| 636 | TREE_DECODE_CHECK(prob, 1 << kNumPosSlotBits, posSlot); |
| 637 | if (posSlot >= kStartPosModelIndex) |
| 638 | { |
| 639 | int numDirectBits = ((posSlot >> 1) - 1); |
| 640 | |
| 641 | /* if (bufLimit - buf >= 8) return DUMMY_MATCH; */ |
| 642 | |
| 643 | if (posSlot < kEndPosModelIndex) |
| 644 | { |
| 645 | prob = probs + SpecPos + ((2 | (posSlot & 1)) << numDirectBits) - posSlot - 1; |
| 646 | } |
| 647 | else |
| 648 | { |
| 649 | numDirectBits -= kNumAlignBits; |
| 650 | do |
| 651 | { |
| 652 | NORMALIZE_CHECK |
| 653 | range >>= 1; |
| 654 | code -= range & (((code - range) >> 31) - 1); |
| 655 | /* if (code >= range) code -= range; */ |
| 656 | } |
| 657 | while (--numDirectBits != 0); |
| 658 | prob = probs + Align; |
| 659 | numDirectBits = kNumAlignBits; |
| 660 | } |
| 661 | { |
| 662 | unsigned i = 1; |
| 663 | do |
| 664 | { |
| 665 | GET_BIT_CHECK(prob + i, i); |
| 666 | } |
| 667 | while (--numDirectBits != 0); |
| 668 | } |
| 669 | } |
| 670 | } |
| 671 | } |
| 672 | } |
| 673 | NORMALIZE_CHECK; |
| 674 | return res; |
| 675 | } |
| 676 | |
| 677 | |
| 678 | static void LzmaDec_InitRc(CLzmaDec *p, const Byte *data) |
| 679 | { |
| 680 | p->code = ((UInt32)data[1] << 24) | ((UInt32)data[2] << 16) | ((UInt32)data[3] << 8) | ((UInt32)data[4]); |
| 681 | p->range = 0xFFFFFFFF; |
| 682 | p->needFlush = 0; |
| 683 | } |
| 684 | |
| 685 | void LzmaDec_InitDicAndState(CLzmaDec *p, Bool initDic, Bool initState) |
| 686 | { |
| 687 | p->needFlush = 1; |
| 688 | p->remainLen = 0; |
| 689 | p->tempBufSize = 0; |
| 690 | |
| 691 | if (initDic) |
| 692 | { |
| 693 | p->processedPos = 0; |
| 694 | p->checkDicSize = 0; |
| 695 | p->needInitState = 1; |
| 696 | } |
| 697 | if (initState) |
| 698 | p->needInitState = 1; |
| 699 | } |
| 700 | |
| 701 | void LzmaDec_Init(CLzmaDec *p) |
| 702 | { |
| 703 | p->dicPos = 0; |
| 704 | LzmaDec_InitDicAndState(p, True, True); |
| 705 | } |
| 706 | |
| 707 | static void LzmaDec_InitStateReal(CLzmaDec *p) |
| 708 | { |
| 709 | UInt32 numProbs = Literal + ((UInt32)LZMA_LIT_SIZE << (p->prop.lc + p->prop.lp)); |
| 710 | UInt32 i; |
| 711 | CLzmaProb *probs = p->probs; |
| 712 | for (i = 0; i < numProbs; i++) |
| 713 | probs[i] = kBitModelTotal >> 1; |
| 714 | p->reps[0] = p->reps[1] = p->reps[2] = p->reps[3] = 1; |
| 715 | p->state = 0; |
| 716 | p->needInitState = 0; |
| 717 | } |
| 718 | |
| 719 | SRes LzmaDec_DecodeToDic(CLzmaDec *p, SizeT dicLimit, const Byte *src, SizeT *srcLen, |
| 720 | ELzmaFinishMode finishMode, ELzmaStatus *status) |
| 721 | { |
| 722 | SizeT inSize = *srcLen; |
| 723 | (*srcLen) = 0; |
| 724 | LzmaDec_WriteRem(p, dicLimit); |
| 725 | |
| 726 | *status = LZMA_STATUS_NOT_SPECIFIED; |
| 727 | |
| 728 | while (p->remainLen != kMatchSpecLenStart) |
| 729 | { |
| 730 | int checkEndMarkNow; |
| 731 | |
| 732 | if (p->needFlush != 0) |
| 733 | { |
| 734 | for (; inSize > 0 && p->tempBufSize < RC_INIT_SIZE; (*srcLen)++, inSize--) |
| 735 | p->tempBuf[p->tempBufSize++] = *src++; |
| 736 | if (p->tempBufSize < RC_INIT_SIZE) |
| 737 | { |
| 738 | *status = LZMA_STATUS_NEEDS_MORE_INPUT; |
| 739 | return SZ_OK; |
| 740 | } |
| 741 | if (p->tempBuf[0] != 0) |
| 742 | return SZ_ERROR_DATA; |
| 743 | |
| 744 | LzmaDec_InitRc(p, p->tempBuf); |
| 745 | p->tempBufSize = 0; |
| 746 | } |
| 747 | |
| 748 | checkEndMarkNow = 0; |
| 749 | if (p->dicPos >= dicLimit) |
| 750 | { |
| 751 | if (p->remainLen == 0 && p->code == 0) |
| 752 | { |
| 753 | *status = LZMA_STATUS_MAYBE_FINISHED_WITHOUT_MARK; |
| 754 | return SZ_OK; |
| 755 | } |
| 756 | if (finishMode == LZMA_FINISH_ANY) |
| 757 | { |
| 758 | *status = LZMA_STATUS_NOT_FINISHED; |
| 759 | return SZ_OK; |
| 760 | } |
| 761 | if (p->remainLen != 0) |
| 762 | { |
| 763 | *status = LZMA_STATUS_NOT_FINISHED; |
| 764 | return SZ_ERROR_DATA; |
| 765 | } |
| 766 | checkEndMarkNow = 1; |
| 767 | } |
| 768 | |
| 769 | if (p->needInitState) |
| 770 | LzmaDec_InitStateReal(p); |
| 771 | |
| 772 | if (p->tempBufSize == 0) |
| 773 | { |
| 774 | SizeT processed; |
| 775 | const Byte *bufLimit; |
| 776 | if (inSize < LZMA_REQUIRED_INPUT_MAX || checkEndMarkNow) |
| 777 | { |
| 778 | int dummyRes = LzmaDec_TryDummy(p, src, inSize); |
| 779 | if (dummyRes == DUMMY_ERROR) |
| 780 | { |
| 781 | memcpy(p->tempBuf, src, inSize); |
| 782 | p->tempBufSize = (unsigned)inSize; |
| 783 | (*srcLen) += inSize; |
| 784 | *status = LZMA_STATUS_NEEDS_MORE_INPUT; |
| 785 | return SZ_OK; |
| 786 | } |
| 787 | if (checkEndMarkNow && dummyRes != DUMMY_MATCH) |
| 788 | { |
| 789 | *status = LZMA_STATUS_NOT_FINISHED; |
| 790 | return SZ_ERROR_DATA; |
| 791 | } |
| 792 | bufLimit = src; |
| 793 | } |
| 794 | else |
| 795 | bufLimit = src + inSize - LZMA_REQUIRED_INPUT_MAX; |
| 796 | p->buf = src; |
| 797 | if (LzmaDec_DecodeReal2(p, dicLimit, bufLimit) != 0) |
| 798 | return SZ_ERROR_DATA; |
| 799 | processed = (SizeT)(p->buf - src); |
| 800 | (*srcLen) += processed; |
| 801 | src += processed; |
| 802 | inSize -= processed; |
| 803 | } |
| 804 | else |
| 805 | { |
| 806 | unsigned rem = p->tempBufSize, lookAhead = 0; |
| 807 | while (rem < LZMA_REQUIRED_INPUT_MAX && lookAhead < inSize) |
| 808 | p->tempBuf[rem++] = src[lookAhead++]; |
| 809 | p->tempBufSize = rem; |
| 810 | if (rem < LZMA_REQUIRED_INPUT_MAX || checkEndMarkNow) |
| 811 | { |
| 812 | int dummyRes = LzmaDec_TryDummy(p, p->tempBuf, rem); |
| 813 | if (dummyRes == DUMMY_ERROR) |
| 814 | { |
| 815 | (*srcLen) += lookAhead; |
| 816 | *status = LZMA_STATUS_NEEDS_MORE_INPUT; |
| 817 | return SZ_OK; |
| 818 | } |
| 819 | if (checkEndMarkNow && dummyRes != DUMMY_MATCH) |
| 820 | { |
| 821 | *status = LZMA_STATUS_NOT_FINISHED; |
| 822 | return SZ_ERROR_DATA; |
| 823 | } |
| 824 | } |
| 825 | p->buf = p->tempBuf; |
| 826 | if (LzmaDec_DecodeReal2(p, dicLimit, p->buf) != 0) |
| 827 | return SZ_ERROR_DATA; |
| 828 | lookAhead -= (rem - (unsigned)(p->buf - p->tempBuf)); |
| 829 | (*srcLen) += lookAhead; |
| 830 | src += lookAhead; |
| 831 | inSize -= lookAhead; |
| 832 | p->tempBufSize = 0; |
| 833 | } |
| 834 | } |
| 835 | if (p->code == 0) |
| 836 | *status = LZMA_STATUS_FINISHED_WITH_MARK; |
| 837 | return (p->code == 0) ? SZ_OK : SZ_ERROR_DATA; |
| 838 | } |
| 839 | |
| 840 | SRes LzmaDec_DecodeToBuf(CLzmaDec *p, Byte *dest, SizeT *destLen, const Byte *src, SizeT *srcLen, ELzmaFinishMode finishMode, ELzmaStatus *status) |
| 841 | { |
| 842 | SizeT outSize = *destLen; |
| 843 | SizeT inSize = *srcLen; |
| 844 | *srcLen = *destLen = 0; |
| 845 | for (;;) |
| 846 | { |
| 847 | SizeT inSizeCur = inSize, outSizeCur, dicPos; |
| 848 | ELzmaFinishMode curFinishMode; |
| 849 | SRes res; |
| 850 | if (p->dicPos == p->dicBufSize) |
| 851 | p->dicPos = 0; |
| 852 | dicPos = p->dicPos; |
| 853 | if (outSize > p->dicBufSize - dicPos) |
| 854 | { |
| 855 | outSizeCur = p->dicBufSize; |
| 856 | curFinishMode = LZMA_FINISH_ANY; |
| 857 | } |
| 858 | else |
| 859 | { |
| 860 | outSizeCur = dicPos + outSize; |
| 861 | curFinishMode = finishMode; |
| 862 | } |
| 863 | |
| 864 | res = LzmaDec_DecodeToDic(p, outSizeCur, src, &inSizeCur, curFinishMode, status); |
| 865 | src += inSizeCur; |
| 866 | inSize -= inSizeCur; |
| 867 | *srcLen += inSizeCur; |
| 868 | outSizeCur = p->dicPos - dicPos; |
| 869 | memcpy(dest, p->dic + dicPos, outSizeCur); |
| 870 | dest += outSizeCur; |
| 871 | outSize -= outSizeCur; |
| 872 | *destLen += outSizeCur; |
| 873 | if (res != 0) |
| 874 | return res; |
| 875 | if (outSizeCur == 0 || outSize == 0) |
| 876 | return SZ_OK; |
| 877 | } |
| 878 | } |
| 879 | |
| 880 | void LzmaDec_FreeProbs(CLzmaDec *p, ISzAlloc *alloc) |
| 881 | { |
| 882 | alloc->Free(alloc, p->probs); |
| 883 | p->probs = 0; |
| 884 | } |
| 885 | |
| 886 | static void LzmaDec_FreeDict(CLzmaDec *p, ISzAlloc *alloc) |
| 887 | { |
| 888 | alloc->Free(alloc, p->dic); |
| 889 | p->dic = 0; |
| 890 | } |
| 891 | |
| 892 | void LzmaDec_Free(CLzmaDec *p, ISzAlloc *alloc) |
| 893 | { |
| 894 | LzmaDec_FreeProbs(p, alloc); |
| 895 | LzmaDec_FreeDict(p, alloc); |
| 896 | } |
| 897 | |
| 898 | SRes LzmaProps_Decode(CLzmaProps *p, const Byte *data, unsigned size) |
| 899 | { |
| 900 | UInt32 dicSize; |
| 901 | Byte d; |
| 902 | |
| 903 | if (size < LZMA_PROPS_SIZE) |
| 904 | return SZ_ERROR_UNSUPPORTED; |
| 905 | else |
| 906 | dicSize = data[1] | ((UInt32)data[2] << 8) | ((UInt32)data[3] << 16) | ((UInt32)data[4] << 24); |
| 907 | |
| 908 | if (dicSize < LZMA_DIC_MIN) |
| 909 | dicSize = LZMA_DIC_MIN; |
| 910 | p->dicSize = dicSize; |
| 911 | |
| 912 | d = data[0]; |
| 913 | if (d >= (9 * 5 * 5)) |
| 914 | return SZ_ERROR_UNSUPPORTED; |
| 915 | |
| 916 | p->lc = d % 9; |
| 917 | d /= 9; |
| 918 | p->pb = d / 5; |
| 919 | p->lp = d % 5; |
| 920 | |
| 921 | return SZ_OK; |
| 922 | } |
| 923 | |
| 924 | static SRes LzmaDec_AllocateProbs2(CLzmaDec *p, const CLzmaProps *propNew, ISzAlloc *alloc) |
| 925 | { |
| 926 | UInt32 numProbs = LzmaProps_GetNumProbs(propNew); |
| 927 | if (p->probs == 0 || numProbs != p->numProbs) |
| 928 | { |
| 929 | LzmaDec_FreeProbs(p, alloc); |
| 930 | p->probs = (CLzmaProb *)alloc->Alloc(alloc, numProbs * sizeof(CLzmaProb)); |
| 931 | p->numProbs = numProbs; |
| 932 | if (p->probs == 0) |
| 933 | return SZ_ERROR_MEM; |
| 934 | } |
| 935 | return SZ_OK; |
| 936 | } |
| 937 | |
| 938 | SRes LzmaDec_AllocateProbs(CLzmaDec *p, const Byte *props, unsigned propsSize, ISzAlloc *alloc) |
| 939 | { |
| 940 | CLzmaProps propNew; |
| 941 | RINOK(LzmaProps_Decode(&propNew, props, propsSize)); |
| 942 | RINOK(LzmaDec_AllocateProbs2(p, &propNew, alloc)); |
| 943 | p->prop = propNew; |
| 944 | return SZ_OK; |
| 945 | } |
| 946 | |
| 947 | SRes LzmaDec_Allocate(CLzmaDec *p, const Byte *props, unsigned propsSize, ISzAlloc *alloc) |
| 948 | { |
| 949 | CLzmaProps propNew; |
| 950 | SizeT dicBufSize; |
| 951 | RINOK(LzmaProps_Decode(&propNew, props, propsSize)); |
| 952 | RINOK(LzmaDec_AllocateProbs2(p, &propNew, alloc)); |
| 953 | dicBufSize = propNew.dicSize; |
| 954 | if (p->dic == 0 || dicBufSize != p->dicBufSize) |
| 955 | { |
| 956 | LzmaDec_FreeDict(p, alloc); |
| 957 | p->dic = (Byte *)alloc->Alloc(alloc, dicBufSize); |
| 958 | if (p->dic == 0) |
| 959 | { |
| 960 | LzmaDec_FreeProbs(p, alloc); |
| 961 | return SZ_ERROR_MEM; |
| 962 | } |
| 963 | } |
| 964 | p->dicBufSize = dicBufSize; |
| 965 | p->prop = propNew; |
| 966 | return SZ_OK; |
| 967 | } |
| 968 | |
| 969 | SRes LzmaDecode(Byte *dest, SizeT *destLen, const Byte *src, SizeT *srcLen, |
| 970 | const Byte *propData, unsigned propSize, ELzmaFinishMode finishMode, |
| 971 | ELzmaStatus *status, ISzAlloc *alloc) |
| 972 | { |
| 973 | CLzmaDec p; |
| 974 | SRes res; |
| 975 | SizeT inSize = *srcLen; |
| 976 | SizeT outSize = *destLen; |
| 977 | *srcLen = *destLen = 0; |
| 978 | if (inSize < RC_INIT_SIZE) |
| 979 | return SZ_ERROR_INPUT_EOF; |
| 980 | |
| 981 | LzmaDec_Construct(&p); |
| 982 | res = LzmaDec_AllocateProbs(&p, propData, propSize, alloc); |
| 983 | if (res != 0) |
| 984 | return res; |
| 985 | p.dic = dest; |
| 986 | p.dicBufSize = outSize; |
| 987 | |
| 988 | LzmaDec_Init(&p); |
| 989 | |
| 990 | *srcLen = inSize; |
| 991 | res = LzmaDec_DecodeToDic(&p, outSize, src, srcLen, finishMode, status); |
| 992 | |
| 993 | if (res == SZ_OK && *status == LZMA_STATUS_NEEDS_MORE_INPUT) |
| 994 | res = SZ_ERROR_INPUT_EOF; |
| 995 | |
| 996 | (*destLen) = p.dicPos; |
| 997 | LzmaDec_FreeProbs(&p, alloc); |
| 998 | return res; |
| 999 | } |