git.cworth.org Git - vogl/blob - src/voglcore/lzma_LzmaDec.cpp

   1 /**************************************************************************
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   3  * Copyright 2013-2014 RAD Game Tools and Valve Software
   4  * Copyright 2010-2014 Rich Geldreich and Tenacious Software LLC
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  23  * THE SOFTWARE.
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  26
  27 /* LzmaDec.c -- LZMA Decoder
  28 2008-11-06 : Igor Pavlov : Public domain */
  29 #include "vogl_core.h"
  30 #include "lzma_LzmaDec.h"
  31
  32 #include <string.h>
  33
  34 namespace vogl
  35 {
  36
  37 #define kNumTopBits 24
  38 #define kTopValue ((UInt32)1 << kNumTopBits)
  39
  40 #define kNumBitModelTotalBits 11
  41 #define kBitModelTotal (1 << kNumBitModelTotalBits)
  42 #define kNumMoveBits 5
  43
  44 #define RC_INIT_SIZE 5
  45
  46 #define NORMALIZE                      \
  47     if (range < kTopValue)             \
  48     {                                  \
  49         range <<= 8;                   \
  50         code = (code << 8) | (*buf++); \
  51     }
  52
  53 #define IF_BIT_0(p)                                 \
  54     ttt = *(p);                                     \
  55     NORMALIZE;                                      \
  56     bound = (range >> kNumBitModelTotalBits) * ttt; \
  57     if (code < bound)
  58 #define UPDATE_0(p) \
  59     range = bound;  \
  60     *(p) = (CLzmaProb)(ttt + ((kBitModelTotal - ttt) >> kNumMoveBits));
  61 #define UPDATE_1(p) \
  62     range -= bound; \
  63     code -= bound;  \
  64     *(p) = (CLzmaProb)(ttt - (ttt >> kNumMoveBits));
  65 #define GET_BIT2(p, i, A0, A1) \
  66     IF_BIT_0(p)                \
  67     {                          \
  68         UPDATE_0(p);           \
  69         i = (i + i);           \
  70         A0;                    \
  71     }                          \
  72     else                       \
  73     {                          \
  74         UPDATE_1(p);           \
  75         i = (i + i) + 1;       \
  76         A1;                    \
  77     }
  78 #define GET_BIT(p, i) GET_BIT2(p, i, ;, ;)
  79
  80 #define TREE_GET_BIT(probs, i)   \
  81     {                            \
  82         GET_BIT((probs + i), i); \
  83     }
  84 #define TREE_DECODE(probs, limit, i) \
  85     {                                \
  86         i = 1;                       \
  87         do                           \
  88         {                            \
  89             TREE_GET_BIT(probs, i);  \
  90         } while (i < limit);         \
  91         i -= limit;                  \
  92     }
  93
  94 /* #define _LZMA_SIZE_OPT */
  95
  96 #ifdef _LZMA_SIZE_OPT
  97 #define TREE_6_DECODE(probs, i) TREE_DECODE(probs, (1 << 6), i)
  98 #else
  99 #define TREE_6_DECODE(probs, i) \
 100     {                           \
 101         i = 1;                  \
 102         TREE_GET_BIT(probs, i); \
 103         TREE_GET_BIT(probs, i); \
 104         TREE_GET_BIT(probs, i); \
 105         TREE_GET_BIT(probs, i); \
 106         TREE_GET_BIT(probs, i); \
 107         TREE_GET_BIT(probs, i); \
 108         i -= 0x40;              \
 109     }
 110 #endif
 111
 112 #define NORMALIZE_CHECK                \
 113     if (range < kTopValue)             \
 114     {                                  \
 115         if (buf >= bufLimit)           \
 116             return DUMMY_ERROR;        \
 117         range <<= 8;                   \
 118         code = (code << 8) | (*buf++); \
 119     }
 120
 121 #define IF_BIT_0_CHECK(p)                           \
 122     ttt = *(p);                                     \
 123     NORMALIZE_CHECK;                                \
 124     bound = (range >> kNumBitModelTotalBits) * ttt; \
 125     if (code < bound)
 126 #define UPDATE_0_CHECK range = bound;
 127 #define UPDATE_1_CHECK \
 128     range -= bound;    \
 129     code -= bound;
 130 #define GET_BIT2_CHECK(p, i, A0, A1) \
 131     IF_BIT_0_CHECK(p)                \
 132     {                                \
 133         UPDATE_0_CHECK;              \
 134         i = (i + i);                 \
 135         A0;                          \
 136     }                                \
 137     else                             \
 138     {                                \
 139         UPDATE_1_CHECK;              \
 140         i = (i + i) + 1;             \
 141         A1;                          \
 142     }
 143 #define GET_BIT_CHECK(p, i) GET_BIT2_CHECK(p, i, ;, ;)
 144 #define TREE_DECODE_CHECK(probs, limit, i) \
 145     {                                      \
 146         i = 1;                             \
 147         do                                 \
 148         {                                  \
 149             GET_BIT_CHECK(probs + i, i)    \
 150         } while (i < limit);               \
 151         i -= limit;                        \
 152     }
 153
 154 #define kNumPosBitsMax 4
 155 #define kNumPosStatesMax (1 << kNumPosBitsMax)
 156
 157 #define kLenNumLowBits 3
 158 #define kLenNumLowSymbols (1 << kLenNumLowBits)
 159 #define kLenNumMidBits 3
 160 #define kLenNumMidSymbols (1 << kLenNumMidBits)
 161 #define kLenNumHighBits 8
 162 #define kLenNumHighSymbols (1 << kLenNumHighBits)
 163
 164 #define LenChoice 0
 165 #define LenChoice2 (LenChoice + 1)
 166 #define LenLow (LenChoice2 + 1)
 167 #define LenMid (LenLow + (kNumPosStatesMax << kLenNumLowBits))
 168 #define LenHigh (LenMid + (kNumPosStatesMax << kLenNumMidBits))
 169 #define kNumLenProbs (LenHigh + kLenNumHighSymbols)
 170
 171 #define kNumStates 12
 172 #define kNumLitStates 7
 173
 174 #define kStartPosModelIndex 4
 175 #define kEndPosModelIndex 14
 176 #define kNumFullDistances (1 << (kEndPosModelIndex >> 1))
 177
 178 #define kNumPosSlotBits 6
 179 #define kNumLenToPosStates 4
 180
 181 #define kNumAlignBits 4
 182 #define kAlignTableSize (1 << kNumAlignBits)
 183
 184 #define kMatchMinLen 2
 185 #define kMatchSpecLenStart (kMatchMinLen + kLenNumLowSymbols + kLenNumMidSymbols + kLenNumHighSymbols)
 186
 187 #define IsMatch 0
 188 #define IsRep (IsMatch + (kNumStates << kNumPosBitsMax))
 189 #define IsRepG0 (IsRep + kNumStates)
 190 #define IsRepG1 (IsRepG0 + kNumStates)
 191 #define IsRepG2 (IsRepG1 + kNumStates)
 192 #define IsRep0Long (IsRepG2 + kNumStates)
 193 #define PosSlot (IsRep0Long + (kNumStates << kNumPosBitsMax))
 194 #define SpecPos (PosSlot + (kNumLenToPosStates << kNumPosSlotBits))
 195 #define Align (SpecPos + kNumFullDistances - kEndPosModelIndex)
 196 #define LenCoder (Align + kAlignTableSize)
 197 #define RepLenCoder (LenCoder + kNumLenProbs)
 198 #define Literal (RepLenCoder + kNumLenProbs)
 199
 200 #define LZMA_BASE_SIZE 1846
 201 #define LZMA_LIT_SIZE 768
 202
 203 #define LzmaProps_GetNumProbs(p) ((UInt32)LZMA_BASE_SIZE + (LZMA_LIT_SIZE << ((p)->lc + (p)->lp)))
 204
 205 #if Literal != LZMA_BASE_SIZE
 206     StopCompilingDueBUG
 207 #endif
 208         static const Byte kLiteralNextStates[kNumStates * 2] =
 209             {
 210                 0, 0, 0, 0, 1, 2, 3, 4, 5, 6, 4, 5,
 211                 7, 7, 7, 7, 7, 7, 7, 10, 10, 10, 10, 10
 212             };
 213
 214 #define LZMA_DIC_MIN (1 << 12)
 215
 216     /* First LZMA-symbol is always decoded.
 217 And it decodes new LZMA-symbols while (buf < bufLimit), but "buf" is without last normalization
 218 Out:
 219   Result:
 220     SZ_OK - OK
 221     SZ_ERROR_DATA - Error
 222   p->remainLen:
 223     < kMatchSpecLenStart : normal remain
 224     = kMatchSpecLenStart : finished
 225     = kMatchSpecLenStart + 1 : Flush marker
 226     = kMatchSpecLenStart + 2 : State Init Marker
 227 */
 228
 229     static int MY_FAST_CALL LzmaDec_DecodeReal(CLzmaDec *p, SizeT limit, const Byte *bufLimit)
 230     {
 231         CLzmaProb *probs = p->probs;
 232
 233         unsigned state = p->state;
 234         UInt32 rep0 = p->reps[0], rep1 = p->reps[1], rep2 = p->reps[2], rep3 = p->reps[3];
 235         unsigned pbMask = ((unsigned)1 << (p->prop.pb)) - 1;
 236         unsigned lpMask = ((unsigned)1 << (p->prop.lp)) - 1;
 237         unsigned lc = p->prop.lc;
 238
 239         Byte *dic = p->dic;
 240         SizeT dicBufSize = p->dicBufSize;
 241         SizeT dicPos = p->dicPos;
 242
 243         UInt32 processedPos = p->processedPos;
 244         UInt32 checkDicSize = p->checkDicSize;
 245         unsigned len = 0;
 246
 247         const Byte *buf = p->buf;
 248         UInt32 range = p->range;
 249         UInt32 code = p->code;
 250
 251         do
 252         {
 253             CLzmaProb *prob;
 254             UInt32 bound;
 255             unsigned ttt;
 256             unsigned posState = processedPos & pbMask;
 257
 258             prob = probs + IsMatch + (state << kNumPosBitsMax) + posState;
 259             IF_BIT_0(prob)
 260             {
 261                 unsigned symbol;
 262                 UPDATE_0(prob);
 263                 prob = probs + Literal;
 264                 if (checkDicSize != 0 || processedPos != 0)
 265                     prob += (LZMA_LIT_SIZE * (((processedPos & lpMask) << lc) +
 266                                               (dic[(dicPos == 0 ? dicBufSize : dicPos) - 1] >> (8 - lc))));
 267
 268                 if (state < kNumLitStates)
 269                 {
 270                     symbol = 1;
 271                     do
 272                     {
 273                         GET_BIT(prob + symbol, symbol)
 274                     } while (symbol < 0x100);
 275                 }
 276                 else
 277                 {
 278                     unsigned matchByte = p->dic[(dicPos - rep0) + ((dicPos < rep0) ? dicBufSize : 0)];
 279                     unsigned offs = 0x100;
 280                     symbol = 1;
 281                     do
 282                     {
 283                         unsigned bit;
 284                         CLzmaProb *probLit;
 285                         matchByte <<= 1;
 286                         bit = (matchByte & offs);
 287                         probLit = prob + offs + bit + symbol;
 288                         GET_BIT2(probLit, symbol, offs &= ~bit, offs &= bit)
 289                     } while (symbol < 0x100);
 290                 }
 291                 dic[dicPos++] = (Byte)symbol;
 292                 processedPos++;
 293
 294                 state = kLiteralNextStates[state];
 295                 /* if (state < 4) state = 0; else if (state < 10) state -= 3; else state -= 6; */
 296                 continue;
 297             }
 298             else
 299             {
 300                 UPDATE_1(prob);
 301                 prob = probs + IsRep + state;
 302                 IF_BIT_0(prob)
 303                 {
 304                     UPDATE_0(prob);
 305                     state += kNumStates;
 306                     prob = probs + LenCoder;
 307                 }
 308                 else
 309                 {
 310                     UPDATE_1(prob);
 311                     if (checkDicSize == 0 && processedPos == 0)
 312                         return SZ_ERROR_DATA;
 313                     prob = probs + IsRepG0 + state;
 314                     IF_BIT_0(prob)
 315                     {
 316                         UPDATE_0(prob);
 317                         prob = probs + IsRep0Long + (state << kNumPosBitsMax) + posState;
 318                         IF_BIT_0(prob)
 319                         {
 320                             UPDATE_0(prob);
 321                             dic[dicPos] = dic[(dicPos - rep0) + ((dicPos < rep0) ? dicBufSize : 0)];
 322                             dicPos++;
 323                             processedPos++;
 324                             state = state < kNumLitStates ? 9 : 11;
 325                             continue;
 326                         }
 327                         UPDATE_1(prob);
 328                     }
 329                     else
 330                     {
 331                         UInt32 distance;
 332                         UPDATE_1(prob);
 333                         prob = probs + IsRepG1 + state;
 334                         IF_BIT_0(prob)
 335                         {
 336                             UPDATE_0(prob);
 337                             distance = rep1;
 338                         }
 339                         else
 340                         {
 341                             UPDATE_1(prob);
 342                             prob = probs + IsRepG2 + state;
 343                             IF_BIT_0(prob)
 344                             {
 345                                 UPDATE_0(prob);
 346                                 distance = rep2;
 347                             }
 348                             else
 349                             {
 350                                 UPDATE_1(prob);
 351                                 distance = rep3;
 352                                 rep3 = rep2;
 353                             }
 354                             rep2 = rep1;
 355                         }
 356                         rep1 = rep0;
 357                         rep0 = distance;
 358                     }
 359                     state = state < kNumLitStates ? 8 : 11;
 360                     prob = probs + RepLenCoder;
 361                 }
 362                 {
 363                     unsigned limit, offset;
 364                     CLzmaProb *probLen = prob + LenChoice;
 365                     IF_BIT_0(probLen)
 366                     {
 367                         UPDATE_0(probLen);
 368                         probLen = prob + LenLow + (posState << kLenNumLowBits);
 369                         offset = 0;
 370                         limit = (1 << kLenNumLowBits);
 371                     }
 372                     else
 373                     {
 374                         UPDATE_1(probLen);
 375                         probLen = prob + LenChoice2;
 376                         IF_BIT_0(probLen)
 377                         {
 378                             UPDATE_0(probLen);
 379                             probLen = prob + LenMid + (posState << kLenNumMidBits);
 380                             offset = kLenNumLowSymbols;
 381                             limit = (1 << kLenNumMidBits);
 382                         }
 383                         else
 384                         {
 385                             UPDATE_1(probLen);
 386                             probLen = prob + LenHigh;
 387                             offset = kLenNumLowSymbols + kLenNumMidSymbols;
 388                             limit = (1 << kLenNumHighBits);
 389                         }
 390                     }
 391                     TREE_DECODE(probLen, limit, len);
 392                     len += offset;
 393                 }
 394
 395                 if (state >= kNumStates)
 396                 {
 397                     UInt32 distance;
 398                     prob = probs + PosSlot +
 399                            ((len < kNumLenToPosStates ? len : kNumLenToPosStates - 1) << kNumPosSlotBits);
 400                     TREE_6_DECODE(prob, distance);
 401                     if (distance >= kStartPosModelIndex)
 402                     {
 403                         unsigned posSlot = (unsigned)distance;
 404                         int numDirectBits = (int)(((distance >> 1) - 1));
 405                         distance = (2 | (distance & 1));
 406                         if (posSlot < kEndPosModelIndex)
 407                         {
 408                             distance <<= numDirectBits;
 409                             prob = probs + SpecPos + distance - posSlot - 1;
 410                             {
 411                                 UInt32 mask = 1;
 412                                 unsigned i = 1;
 413                                 do
 414                                 {
 415                                     GET_BIT2(prob + i, i, ;, distance |= mask);
 416                                     mask <<= 1;
 417                                 } while (--numDirectBits != 0);
 418                             }
 419                         }
 420                         else
 421                         {
 422                             numDirectBits -= kNumAlignBits;
 423                             do
 424                             {
 425                                 NORMALIZE
 426                                 range >>= 1;
 427
 428                                 {
 429                                     UInt32 t;
 430                                     code -= range;
 431                                     t = (0 - ((UInt32)code >> 31)); /* (UInt32)((Int32)code >> 31) */
 432                                     distance = (distance << 1) + (t + 1);
 433                                     code += range & t;
 434                                 }
 435                                 /*
 436                                                         distance <<= 1;
 437                                                         if (code >= range)
 438                                                         {
 439                                                           code -= range;
 440                                                           distance |= 1;
 441                                                         }
 442                                                         */
 443                             } while (--numDirectBits != 0);
 444                             prob = probs + Align;
 445                             distance <<= kNumAlignBits;
 446                             {
 447                                 unsigned i = 1;
 448                                 GET_BIT2(prob + i, i, ;, distance |= 1);
 449                                 GET_BIT2(prob + i, i, ;, distance |= 2);
 450                                 GET_BIT2(prob + i, i, ;, distance |= 4);
 451                                 GET_BIT2(prob + i, i, ;, distance |= 8);
 452                             }
 453                             if (distance == (UInt32)0xFFFFFFFF)
 454                             {
 455                                 len += kMatchSpecLenStart;
 456                                 state -= kNumStates;
 457                                 break;
 458                             }
 459                         }
 460                     }
 461                     rep3 = rep2;
 462                     rep2 = rep1;
 463                     rep1 = rep0;
 464                     rep0 = distance + 1;
 465                     if (checkDicSize == 0)
 466                     {
 467                         if (distance >= processedPos)
 468                             return SZ_ERROR_DATA;
 469                     }
 470                     else if (distance >= checkDicSize)
 471                         return SZ_ERROR_DATA;
 472                     state = (state < kNumStates + kNumLitStates) ? kNumLitStates : kNumLitStates + 3;
 473                     /* state = kLiteralNextStates[state]; */
 474                 }
 475
 476                 len += kMatchMinLen;
 477
 478                 if (limit == dicPos)
 479                     return SZ_ERROR_DATA;
 480                 {
 481                     SizeT rem = limit - dicPos;
 482                     unsigned curLen = ((rem < len) ? (unsigned)rem : len);
 483                     SizeT pos = (dicPos - rep0) + ((dicPos < rep0) ? dicBufSize : 0);
 484
 485                     processedPos += curLen;
 486
 487                     len -= curLen;
 488                     if (pos + curLen <= dicBufSize)
 489                     {
 490                         Byte *dest = dic + dicPos;
 491                         ptrdiff_t src = (ptrdiff_t)pos - (ptrdiff_t)dicPos;
 492                         const Byte *lim = dest + curLen;
 493                         dicPos += curLen;
 494                         do
 495                             *(dest) = (Byte) * (dest + src);
 496                         while (++dest != lim);
 497                     }
 498                     else
 499                     {
 500                         do
 501                         {
 502                             dic[dicPos++] = dic[pos];
 503                             if (++pos == dicBufSize)
 504                                 pos = 0;
 505                         } while (--curLen != 0);
 506                     }
 507                 }
 508             }
 509         } while (dicPos < limit && buf < bufLimit);
 510         NORMALIZE;
 511         p->buf = buf;
 512         p->range = range;
 513         p->code = code;
 514         p->remainLen = len;
 515         p->dicPos = dicPos;
 516         p->processedPos = processedPos;
 517         p->reps[0] = rep0;
 518         p->reps[1] = rep1;
 519         p->reps[2] = rep2;
 520         p->reps[3] = rep3;
 521         p->state = state;
 522
 523         return SZ_OK;
 524     }
 525
 526     static void MY_FAST_CALL LzmaDec_WriteRem(CLzmaDec *p, SizeT limit)
 527     {
 528         if (p->remainLen != 0 && p->remainLen < kMatchSpecLenStart)
 529         {
 530             Byte *dic = p->dic;
 531             SizeT dicPos = p->dicPos;
 532             SizeT dicBufSize = p->dicBufSize;
 533             unsigned len = p->remainLen;
 534             UInt32 rep0 = p->reps[0];
 535             if (limit - dicPos < len)
 536                 len = (unsigned)(limit - dicPos);
 537
 538             if (p->checkDicSize == 0 && p->prop.dicSize - p->processedPos <= len)
 539                 p->checkDicSize = p->prop.dicSize;
 540
 541             p->processedPos += len;
 542             p->remainLen -= len;
 543             while (len-- != 0)
 544             {
 545                 dic[dicPos] = dic[(dicPos - rep0) + ((dicPos < rep0) ? dicBufSize : 0)];
 546                 dicPos++;
 547             }
 548             p->dicPos = dicPos;
 549         }
 550     }
 551
 552     static int MY_FAST_CALL LzmaDec_DecodeReal2(CLzmaDec *p, SizeT limit, const Byte *bufLimit)
 553     {
 554         do
 555         {
 556             SizeT limit2 = limit;
 557             if (p->checkDicSize == 0)
 558             {
 559                 UInt32 rem = p->prop.dicSize - p->processedPos;
 560                 if (limit - p->dicPos > rem)
 561                     limit2 = p->dicPos + rem;
 562             }
 563             RINOK(LzmaDec_DecodeReal(p, limit2, bufLimit));
 564             if (p->processedPos >= p->prop.dicSize)
 565                 p->checkDicSize = p->prop.dicSize;
 566             LzmaDec_WriteRem(p, limit);
 567         } while (p->dicPos < limit && p->buf < bufLimit && p->remainLen < kMatchSpecLenStart);
 568
 569         if (p->remainLen > kMatchSpecLenStart)
 570         {
 571             p->remainLen = kMatchSpecLenStart;
 572         }
 573         return 0;
 574     }
 575
 576     typedef enum
 577     {
 578         DUMMY_ERROR, /* unexpected end of input stream */
 579         DUMMY_LIT,
 580         DUMMY_MATCH,
 581         DUMMY_REP
 582     } ELzmaDummy;
 583
 584     static ELzmaDummy LzmaDec_TryDummy(const CLzmaDec *p, const Byte *buf, SizeT inSize)
 585     {
 586         UInt32 range = p->range;
 587         UInt32 code = p->code;
 588         const Byte *bufLimit = buf + inSize;
 589         CLzmaProb *probs = p->probs;
 590         unsigned state = p->state;
 591         ELzmaDummy res;
 592
 593         {
 594             CLzmaProb *prob;
 595             UInt32 bound;
 596             unsigned ttt;
 597             unsigned posState = (p->processedPos) & ((1 << p->prop.pb) - 1);
 598
 599             prob = probs + IsMatch + (state << kNumPosBitsMax) + posState;
 600             IF_BIT_0_CHECK(prob)
 601             {
 602                 UPDATE_0_CHECK
 603
 604                 /* if (bufLimit - buf >= 7) return DUMMY_LIT; */
 605
 606                 prob = probs + Literal;
 607                 if (p->checkDicSize != 0 || p->processedPos != 0)
 608                     prob += (LZMA_LIT_SIZE *
 609                              ((((p->processedPos) & ((1 << (p->prop.lp)) - 1)) << p->prop.lc) +
 610                               (p->dic[(p->dicPos == 0 ? p->dicBufSize : p->dicPos) - 1] >> (8 - p->prop.lc))));
 611
 612                 if (state < kNumLitStates)
 613                 {
 614                     unsigned symbol = 1;
 615                     do
 616                     {
 617                         GET_BIT_CHECK(prob + symbol, symbol)
 618                     } while (symbol < 0x100);
 619                 }
 620                 else
 621                 {
 622                     unsigned matchByte = p->dic[p->dicPos - p->reps[0] +
 623                                                 ((p->dicPos < p->reps[0]) ? p->dicBufSize : 0)];
 624                     unsigned offs = 0x100;
 625                     unsigned symbol = 1;
 626                     do
 627                     {
 628                         unsigned bit;
 629                         CLzmaProb *probLit;
 630                         matchByte <<= 1;
 631                         bit = (matchByte & offs);
 632                         probLit = prob + offs + bit + symbol;
 633                         GET_BIT2_CHECK(probLit, symbol, offs &= ~bit, offs &= bit)
 634                     } while (symbol < 0x100);
 635                 }
 636                 res = DUMMY_LIT;
 637             }
 638             else
 639             {
 640                 unsigned len;
 641                 UPDATE_1_CHECK;
 642
 643                 prob = probs + IsRep + state;
 644                 IF_BIT_0_CHECK(prob)
 645                 {
 646                     UPDATE_0_CHECK;
 647                     state = 0;
 648                     prob = probs + LenCoder;
 649                     res = DUMMY_MATCH;
 650                 }
 651                 else
 652                 {
 653                     UPDATE_1_CHECK;
 654                     res = DUMMY_REP;
 655                     prob = probs + IsRepG0 + state;
 656                     IF_BIT_0_CHECK(prob)
 657                     {
 658                         UPDATE_0_CHECK;
 659                         prob = probs + IsRep0Long + (state << kNumPosBitsMax) + posState;
 660                         IF_BIT_0_CHECK(prob)
 661                         {
 662                             UPDATE_0_CHECK;
 663                             NORMALIZE_CHECK;
 664                             return DUMMY_REP;
 665                         }
 666                         else
 667                         {
 668                             UPDATE_1_CHECK;
 669                         }
 670                     }
 671                     else
 672                     {
 673                         UPDATE_1_CHECK;
 674                         prob = probs + IsRepG1 + state;
 675                         IF_BIT_0_CHECK(prob)
 676                         {
 677                             UPDATE_0_CHECK;
 678                         }
 679                         else
 680                         {
 681                             UPDATE_1_CHECK;
 682                             prob = probs + IsRepG2 + state;
 683                             IF_BIT_0_CHECK(prob)
 684                             {
 685                                 UPDATE_0_CHECK;
 686                             }
 687                             else
 688                             {
 689                                 UPDATE_1_CHECK;
 690                             }
 691                         }
 692                     }
 693                     state = kNumStates;
 694                     prob = probs + RepLenCoder;
 695                 }
 696                 {
 697                     unsigned limit, offset;
 698                     CLzmaProb *probLen = prob + LenChoice;
 699                     IF_BIT_0_CHECK(probLen)
 700                     {
 701                         UPDATE_0_CHECK;
 702                         probLen = prob + LenLow + (posState << kLenNumLowBits);
 703                         offset = 0;
 704                         limit = 1 << kLenNumLowBits;
 705                     }
 706                     else
 707                     {
 708                         UPDATE_1_CHECK;
 709                         probLen = prob + LenChoice2;
 710                         IF_BIT_0_CHECK(probLen)
 711                         {
 712                             UPDATE_0_CHECK;
 713                             probLen = prob + LenMid + (posState << kLenNumMidBits);
 714                             offset = kLenNumLowSymbols;
 715                             limit = 1 << kLenNumMidBits;
 716                         }
 717                         else
 718                         {
 719                             UPDATE_1_CHECK;
 720                             probLen = prob + LenHigh;
 721                             offset = kLenNumLowSymbols + kLenNumMidSymbols;
 722                             limit = 1 << kLenNumHighBits;
 723                         }
 724                     }
 725                     TREE_DECODE_CHECK(probLen, limit, len);
 726                     len += offset;
 727                 }
 728
 729                 if (state < 4)
 730                 {
 731                     unsigned posSlot;
 732                     prob = probs + PosSlot +
 733                            ((len < kNumLenToPosStates ? len : kNumLenToPosStates - 1) << kNumPosSlotBits);
 734                     TREE_DECODE_CHECK(prob, 1 << kNumPosSlotBits, posSlot);
 735                     if (posSlot >= kStartPosModelIndex)
 736                     {
 737                         int numDirectBits = ((posSlot >> 1) - 1);
 738
 739                         /* if (bufLimit - buf >= 8) return DUMMY_MATCH; */
 740
 741                         if (posSlot < kEndPosModelIndex)
 742                         {
 743                             prob = probs + SpecPos + ((2 | (posSlot & 1)) << numDirectBits) - posSlot - 1;
 744                         }
 745                         else
 746                         {
 747                             numDirectBits -= kNumAlignBits;
 748                             do
 749                             {
 750                                 NORMALIZE_CHECK
 751                                 range >>= 1;
 752                                 code -= range & (((code - range) >> 31) - 1);
 753                                 /* if (code >= range) code -= range; */
 754                             } while (--numDirectBits != 0);
 755                             prob = probs + Align;
 756                             numDirectBits = kNumAlignBits;
 757                         }
 758                         {
 759                             unsigned i = 1;
 760                             do
 761                             {
 762                                 GET_BIT_CHECK(prob + i, i);
 763                             } while (--numDirectBits != 0);
 764                         }
 765                     }
 766                 }
 767             }
 768         }
 769         NORMALIZE_CHECK;
 770         return res;
 771     }
 772
 773     static void LzmaDec_InitRc(CLzmaDec *p, const Byte *data)
 774     {
 775         p->code = ((UInt32)data[1] << 24) | ((UInt32)data[2] << 16) | ((UInt32)data[3] << 8) | ((UInt32)data[4]);
 776         p->range = 0xFFFFFFFF;
 777         p->needFlush = 0;
 778     }
 779
 780     void LzmaDec_InitDicAndState(CLzmaDec *p, Bool initDic, Bool initState)
 781     {
 782         p->needFlush = 1;
 783         p->remainLen = 0;
 784         p->tempBufSize = 0;
 785
 786         if (initDic)
 787         {
 788             p->processedPos = 0;
 789             p->checkDicSize = 0;
 790             p->needInitState = 1;
 791         }
 792         if (initState)
 793             p->needInitState = 1;
 794     }
 795
 796     void LzmaDec_Init(CLzmaDec *p)
 797     {
 798         p->dicPos = 0;
 799         LzmaDec_InitDicAndState(p, True, True);
 800     }
 801
 802     static void LzmaDec_InitStateReal(CLzmaDec *p)
 803     {
 804         UInt32 numProbs = Literal + ((UInt32)LZMA_LIT_SIZE << (p->prop.lc + p->prop.lp));
 805         UInt32 i;
 806         CLzmaProb *probs = p->probs;
 807         for (i = 0; i < numProbs; i++)
 808             probs[i] = kBitModelTotal >> 1;
 809         p->reps[0] = p->reps[1] = p->reps[2] = p->reps[3] = 1;
 810         p->state = 0;
 811         p->needInitState = 0;
 812     }
 813
 814     SRes LzmaDec_DecodeToDic(CLzmaDec *p, SizeT dicLimit, const Byte *src, SizeT *srcLen,
 815                              ELzmaFinishMode finishMode, ELzmaStatus *status)
 816     {
 817         SizeT inSize = *srcLen;
 818         (*srcLen) = 0;
 819         LzmaDec_WriteRem(p, dicLimit);
 820
 821         *status = LZMA_STATUS_NOT_SPECIFIED;
 822
 823         while (p->remainLen != kMatchSpecLenStart)
 824         {
 825             int checkEndMarkNow;
 826
 827             if (p->needFlush != 0)
 828             {
 829                 for (; inSize > 0 && p->tempBufSize < RC_INIT_SIZE; (*srcLen)++, inSize--)
 830                     p->tempBuf[p->tempBufSize++] = *src++;
 831                 if (p->tempBufSize < RC_INIT_SIZE)
 832                 {
 833                     *status = LZMA_STATUS_NEEDS_MORE_INPUT;
 834                     return SZ_OK;
 835                 }
 836                 if (p->tempBuf[0] != 0)
 837                     return SZ_ERROR_DATA;
 838
 839                 LzmaDec_InitRc(p, p->tempBuf);
 840                 p->tempBufSize = 0;
 841             }
 842
 843             checkEndMarkNow = 0;
 844             if (p->dicPos >= dicLimit)
 845             {
 846                 if (p->remainLen == 0 && p->code == 0)
 847                 {
 848                     *status = LZMA_STATUS_MAYBE_FINISHED_WITHOUT_MARK;
 849                     return SZ_OK;
 850                 }
 851                 if (finishMode == LZMA_FINISH_ANY)
 852                 {
 853                     *status = LZMA_STATUS_NOT_FINISHED;
 854                     return SZ_OK;
 855                 }
 856                 if (p->remainLen != 0)
 857                 {
 858                     *status = LZMA_STATUS_NOT_FINISHED;
 859                     return SZ_ERROR_DATA;
 860                 }
 861                 checkEndMarkNow = 1;
 862             }
 863
 864             if (p->needInitState)
 865                 LzmaDec_InitStateReal(p);
 866
 867             if (p->tempBufSize == 0)
 868             {
 869                 SizeT processed;
 870                 const Byte *bufLimit;
 871                 if (inSize < LZMA_REQUIRED_INPUT_MAX || checkEndMarkNow)
 872                 {
 873                     int dummyRes = LzmaDec_TryDummy(p, src, inSize);
 874                     if (dummyRes == DUMMY_ERROR)
 875                     {
 876                         memcpy(p->tempBuf, src, inSize);
 877                         p->tempBufSize = (unsigned)inSize;
 878                         (*srcLen) += inSize;
 879                         *status = LZMA_STATUS_NEEDS_MORE_INPUT;
 880                         return SZ_OK;
 881                     }
 882                     if (checkEndMarkNow && dummyRes != DUMMY_MATCH)
 883                     {
 884                         *status = LZMA_STATUS_NOT_FINISHED;
 885                         return SZ_ERROR_DATA;
 886                     }
 887                     bufLimit = src;
 888                 }
 889                 else
 890                     bufLimit = src + inSize - LZMA_REQUIRED_INPUT_MAX;
 891                 p->buf = src;
 892                 if (LzmaDec_DecodeReal2(p, dicLimit, bufLimit) != 0)
 893                     return SZ_ERROR_DATA;
 894                 processed = (SizeT)(p->buf - src);
 895                 (*srcLen) += processed;
 896                 src += processed;
 897                 inSize -= processed;
 898             }
 899             else
 900             {
 901                 unsigned rem = p->tempBufSize, lookAhead = 0;
 902                 while (rem < LZMA_REQUIRED_INPUT_MAX && lookAhead < inSize)
 903                     p->tempBuf[rem++] = src[lookAhead++];
 904                 p->tempBufSize = rem;
 905                 if (rem < LZMA_REQUIRED_INPUT_MAX || checkEndMarkNow)
 906                 {
 907                     int dummyRes = LzmaDec_TryDummy(p, p->tempBuf, rem);
 908                     if (dummyRes == DUMMY_ERROR)
 909                     {
 910                         (*srcLen) += lookAhead;
 911                         *status = LZMA_STATUS_NEEDS_MORE_INPUT;
 912                         return SZ_OK;
 913                     }
 914                     if (checkEndMarkNow && dummyRes != DUMMY_MATCH)
 915                     {
 916                         *status = LZMA_STATUS_NOT_FINISHED;
 917                         return SZ_ERROR_DATA;
 918                     }
 919                 }
 920                 p->buf = p->tempBuf;
 921                 if (LzmaDec_DecodeReal2(p, dicLimit, p->buf) != 0)
 922                     return SZ_ERROR_DATA;
 923                 lookAhead -= (rem - (unsigned)(p->buf - p->tempBuf));
 924                 (*srcLen) += lookAhead;
 925                 src += lookAhead;
 926                 inSize -= lookAhead;
 927                 p->tempBufSize = 0;
 928             }
 929         }
 930         if (p->code == 0)
 931             *status = LZMA_STATUS_FINISHED_WITH_MARK;
 932         return (p->code == 0) ? SZ_OK : SZ_ERROR_DATA;
 933     }
 934
 935     SRes LzmaDec_DecodeToBuf(CLzmaDec *p, Byte *dest, SizeT *destLen, const Byte *src, SizeT *srcLen, ELzmaFinishMode finishMode, ELzmaStatus *status)
 936     {
 937         SizeT outSize = *destLen;
 938         SizeT inSize = *srcLen;
 939         *srcLen = *destLen = 0;
 940         for (;;)
 941         {
 942             SizeT inSizeCur = inSize, outSizeCur, dicPos;
 943             ELzmaFinishMode curFinishMode;
 944             SRes res;
 945             if (p->dicPos == p->dicBufSize)
 946                 p->dicPos = 0;
 947             dicPos = p->dicPos;
 948             if (outSize > p->dicBufSize - dicPos)
 949             {
 950                 outSizeCur = p->dicBufSize;
 951                 curFinishMode = LZMA_FINISH_ANY;
 952             }
 953             else
 954             {
 955                 outSizeCur = dicPos + outSize;
 956                 curFinishMode = finishMode;
 957             }
 958
 959             res = LzmaDec_DecodeToDic(p, outSizeCur, src, &inSizeCur, curFinishMode, status);
 960             src += inSizeCur;
 961             inSize -= inSizeCur;
 962             *srcLen += inSizeCur;
 963             outSizeCur = p->dicPos - dicPos;
 964             memcpy(dest, p->dic + dicPos, outSizeCur);
 965             dest += outSizeCur;
 966             outSize -= outSizeCur;
 967             *destLen += outSizeCur;
 968             if (res != 0)
 969                 return res;
 970             if (outSizeCur == 0 || outSize == 0)
 971                 return SZ_OK;
 972         }
 973     }
 974
 975     void LzmaDec_FreeProbs(CLzmaDec *p, ISzAlloc *alloc)
 976     {
 977         alloc->Free(alloc, p->probs);
 978         p->probs = 0;
 979     }
 980
 981     static void LzmaDec_FreeDict(CLzmaDec *p, ISzAlloc *alloc)
 982     {
 983         alloc->Free(alloc, p->dic);
 984         p->dic = 0;
 985     }
 986
 987     void LzmaDec_Free(CLzmaDec *p, ISzAlloc *alloc)
 988     {
 989         LzmaDec_FreeProbs(p, alloc);
 990         LzmaDec_FreeDict(p, alloc);
 991     }
 992
 993     SRes LzmaProps_Decode(CLzmaProps *p, const Byte *data, unsigned size)
 994     {
 995         UInt32 dicSize;
 996         Byte d;
 997
 998         if (size < LZMA_PROPS_SIZE)
 999             return SZ_ERROR_UNSUPPORTED;
1000         else
1001             dicSize = data[1] | ((UInt32)data[2] << 8) | ((UInt32)data[3] << 16) | ((UInt32)data[4] << 24);
1002
1003         if (dicSize < LZMA_DIC_MIN)
1004             dicSize = LZMA_DIC_MIN;
1005         p->dicSize = dicSize;
1006
1007         d = data[0];
1008         if (d >= (9 * 5 * 5))
1009             return SZ_ERROR_UNSUPPORTED;
1010
1011         p->lc = d % 9;
1012         d /= 9;
1013         p->pb = d / 5;
1014         p->lp = d % 5;
1015
1016         return SZ_OK;
1017     }
1018
1019     static SRes LzmaDec_AllocateProbs2(CLzmaDec *p, const CLzmaProps *propNew, ISzAlloc *alloc)
1020     {
1021         UInt32 numProbs = LzmaProps_GetNumProbs(propNew);
1022         if (p->probs == 0 || numProbs != p->numProbs)
1023         {
1024             LzmaDec_FreeProbs(p, alloc);
1025             p->probs = (CLzmaProb *)alloc->Alloc(alloc, numProbs * sizeof(CLzmaProb));
1026             p->numProbs = numProbs;
1027             if (p->probs == 0)
1028                 return SZ_ERROR_MEM;
1029         }
1030         return SZ_OK;
1031     }
1032
1033     SRes LzmaDec_AllocateProbs(CLzmaDec *p, const Byte *props, unsigned propsSize, ISzAlloc *alloc)
1034     {
1035         CLzmaProps propNew;
1036         RINOK(LzmaProps_Decode(&propNew, props, propsSize));
1037         RINOK(LzmaDec_AllocateProbs2(p, &propNew, alloc));
1038         p->prop = propNew;
1039         return SZ_OK;
1040     }
1041
1042     SRes LzmaDec_Allocate(CLzmaDec *p, const Byte *props, unsigned propsSize, ISzAlloc *alloc)
1043     {
1044         CLzmaProps propNew;
1045         SizeT dicBufSize;
1046         RINOK(LzmaProps_Decode(&propNew, props, propsSize));
1047         RINOK(LzmaDec_AllocateProbs2(p, &propNew, alloc));
1048         dicBufSize = propNew.dicSize;
1049         if (p->dic == 0 || dicBufSize != p->dicBufSize)
1050         {
1051             LzmaDec_FreeDict(p, alloc);
1052             p->dic = (Byte *)alloc->Alloc(alloc, dicBufSize);
1053             if (p->dic == 0)
1054             {
1055                 LzmaDec_FreeProbs(p, alloc);
1056                 return SZ_ERROR_MEM;
1057             }
1058         }
1059         p->dicBufSize = dicBufSize;
1060         p->prop = propNew;
1061         return SZ_OK;
1062     }
1063
1064     SRes LzmaDecode(Byte *dest, SizeT *destLen, const Byte *src, SizeT *srcLen,
1065                     const Byte *propData, unsigned propSize, ELzmaFinishMode finishMode,
1066                     ELzmaStatus *status, ISzAlloc *alloc)
1067     {
1068         CLzmaDec p;
1069         SRes res;
1070         SizeT inSize = *srcLen;
1071         SizeT outSize = *destLen;
1072         *srcLen = *destLen = 0;
1073         if (inSize < RC_INIT_SIZE)
1074             return SZ_ERROR_INPUT_EOF;
1075
1076         LzmaDec_Construct(&p);
1077         res = LzmaDec_AllocateProbs(&p, propData, propSize, alloc);
1078         if (res != 0)
1079             return res;
1080         p.dic = dest;
1081         p.dicBufSize = outSize;
1082
1083         LzmaDec_Init(&p);
1084
1085         *srcLen = inSize;
1086         res = LzmaDec_DecodeToDic(&p, outSize, src, srcLen, finishMode, status);
1087
1088         if (res == SZ_OK && *status == LZMA_STATUS_NEEDS_MORE_INPUT)
1089             res = SZ_ERROR_INPUT_EOF;
1090
1091         (*destLen) = p.dicPos;
1092         LzmaDec_FreeProbs(&p, alloc);
1093         return res;
1094     }
1095 }