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mGBA Game Boy Advance Emulator

src/third-party/lzma/LzmaDec.c (view raw)

   1/* LzmaDec.c -- LZMA Decoder
   22015-01-01 : Igor Pavlov : Public domain */
   3
   4#include "Precomp.h"
   5
   6#include "LzmaDec.h"
   7
   8#include <string.h>
   9
  10#define kNumTopBits 24
  11#define kTopValue ((UInt32)1 << kNumTopBits)
  12
  13#define kNumBitModelTotalBits 11
  14#define kBitModelTotal (1 << kNumBitModelTotalBits)
  15#define kNumMoveBits 5
  16
  17#define RC_INIT_SIZE 5
  18
  19#define NORMALIZE if (range < kTopValue) { range <<= 8; code = (code << 8) | (*buf++); }
  20
  21#define IF_BIT_0(p) ttt = *(p); NORMALIZE; bound = (range >> kNumBitModelTotalBits) * ttt; if (code < bound)
  22#define UPDATE_0(p) range = bound; *(p) = (CLzmaProb)(ttt + ((kBitModelTotal - ttt) >> kNumMoveBits));
  23#define UPDATE_1(p) range -= bound; code -= bound; *(p) = (CLzmaProb)(ttt - (ttt >> kNumMoveBits));
  24#define GET_BIT2(p, i, A0, A1) IF_BIT_0(p) \
  25  { UPDATE_0(p); i = (i + i); A0; } else \
  26  { UPDATE_1(p); i = (i + i) + 1; A1; }
  27#define GET_BIT(p, i) GET_BIT2(p, i, ; , ;)
  28
  29#define TREE_GET_BIT(probs, i) { GET_BIT((probs + i), i); }
  30#define TREE_DECODE(probs, limit, i) \
  31  { i = 1; do { TREE_GET_BIT(probs, i); } while (i < limit); i -= limit; }
  32
  33/* #define _LZMA_SIZE_OPT */
  34
  35#ifdef _LZMA_SIZE_OPT
  36#define TREE_6_DECODE(probs, i) TREE_DECODE(probs, (1 << 6), i)
  37#else
  38#define TREE_6_DECODE(probs, i) \
  39  { i = 1; \
  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  TREE_GET_BIT(probs, i); \
  45  TREE_GET_BIT(probs, i); \
  46  i -= 0x40; }
  47#endif
  48
  49#define NORMAL_LITER_DEC GET_BIT(prob + symbol, symbol)
  50#define MATCHED_LITER_DEC \
  51  matchByte <<= 1; \
  52  bit = (matchByte & offs); \
  53  probLit = prob + offs + bit + symbol; \
  54  GET_BIT2(probLit, symbol, offs &= ~bit, offs &= bit)
  55
  56#define NORMALIZE_CHECK if (range < kTopValue) { if (buf >= bufLimit) return DUMMY_ERROR; range <<= 8; code = (code << 8) | (*buf++); }
  57
  58#define IF_BIT_0_CHECK(p) ttt = *(p); NORMALIZE_CHECK; bound = (range >> kNumBitModelTotalBits) * ttt; if (code < bound)
  59#define UPDATE_0_CHECK range = bound;
  60#define UPDATE_1_CHECK range -= bound; code -= bound;
  61#define GET_BIT2_CHECK(p, i, A0, A1) IF_BIT_0_CHECK(p) \
  62  { UPDATE_0_CHECK; i = (i + i); A0; } else \
  63  { UPDATE_1_CHECK; i = (i + i) + 1; A1; }
  64#define GET_BIT_CHECK(p, i) GET_BIT2_CHECK(p, i, ; , ;)
  65#define TREE_DECODE_CHECK(probs, limit, i) \
  66  { i = 1; do { GET_BIT_CHECK(probs + i, i) } while (i < limit); i -= limit; }
  67
  68
  69#define kNumPosBitsMax 4
  70#define kNumPosStatesMax (1 << kNumPosBitsMax)
  71
  72#define kLenNumLowBits 3
  73#define kLenNumLowSymbols (1 << kLenNumLowBits)
  74#define kLenNumMidBits 3
  75#define kLenNumMidSymbols (1 << kLenNumMidBits)
  76#define kLenNumHighBits 8
  77#define kLenNumHighSymbols (1 << kLenNumHighBits)
  78
  79#define LenChoice 0
  80#define LenChoice2 (LenChoice + 1)
  81#define LenLow (LenChoice2 + 1)
  82#define LenMid (LenLow + (kNumPosStatesMax << kLenNumLowBits))
  83#define LenHigh (LenMid + (kNumPosStatesMax << kLenNumMidBits))
  84#define kNumLenProbs (LenHigh + kLenNumHighSymbols)
  85
  86
  87#define kNumStates 12
  88#define kNumLitStates 7
  89
  90#define kStartPosModelIndex 4
  91#define kEndPosModelIndex 14
  92#define kNumFullDistances (1 << (kEndPosModelIndex >> 1))
  93
  94#define kNumPosSlotBits 6
  95#define kNumLenToPosStates 4
  96
  97#define kNumAlignBits 4
  98#define kAlignTableSize (1 << kNumAlignBits)
  99
 100#define kMatchMinLen 2
 101#define kMatchSpecLenStart (kMatchMinLen + kLenNumLowSymbols + kLenNumMidSymbols + kLenNumHighSymbols)
 102
 103#define IsMatch 0
 104#define IsRep (IsMatch + (kNumStates << kNumPosBitsMax))
 105#define IsRepG0 (IsRep + kNumStates)
 106#define IsRepG1 (IsRepG0 + kNumStates)
 107#define IsRepG2 (IsRepG1 + kNumStates)
 108#define IsRep0Long (IsRepG2 + kNumStates)
 109#define PosSlot (IsRep0Long + (kNumStates << kNumPosBitsMax))
 110#define SpecPos (PosSlot + (kNumLenToPosStates << kNumPosSlotBits))
 111#define Align (SpecPos + kNumFullDistances - kEndPosModelIndex)
 112#define LenCoder (Align + kAlignTableSize)
 113#define RepLenCoder (LenCoder + kNumLenProbs)
 114#define Literal (RepLenCoder + kNumLenProbs)
 115
 116#define LZMA_BASE_SIZE 1846
 117#define LZMA_LIT_SIZE 768
 118
 119#define LzmaProps_GetNumProbs(p) ((UInt32)LZMA_BASE_SIZE + (LZMA_LIT_SIZE << ((p)->lc + (p)->lp)))
 120
 121#if Literal != LZMA_BASE_SIZE
 122StopCompilingDueBUG
 123#endif
 124
 125#define LZMA_DIC_MIN (1 << 12)
 126
 127/* First LZMA-symbol is always decoded.
 128And it decodes new LZMA-symbols while (buf < bufLimit), but "buf" is without last normalization
 129Out:
 130  Result:
 131    SZ_OK - OK
 132    SZ_ERROR_DATA - Error
 133  p->remainLen:
 134    < kMatchSpecLenStart : normal remain
 135    = kMatchSpecLenStart : finished
 136    = kMatchSpecLenStart + 1 : Flush marker
 137    = kMatchSpecLenStart + 2 : State Init Marker
 138*/
 139
 140static int MY_FAST_CALL LzmaDec_DecodeReal(CLzmaDec *p, SizeT limit, const Byte *bufLimit)
 141{
 142  CLzmaProb *probs = p->probs;
 143
 144  unsigned state = p->state;
 145  UInt32 rep0 = p->reps[0], rep1 = p->reps[1], rep2 = p->reps[2], rep3 = p->reps[3];
 146  unsigned pbMask = ((unsigned)1 << (p->prop.pb)) - 1;
 147  unsigned lpMask = ((unsigned)1 << (p->prop.lp)) - 1;
 148  unsigned lc = p->prop.lc;
 149
 150  Byte *dic = p->dic;
 151  SizeT dicBufSize = p->dicBufSize;
 152  SizeT dicPos = p->dicPos;
 153  
 154  UInt32 processedPos = p->processedPos;
 155  UInt32 checkDicSize = p->checkDicSize;
 156  unsigned len = 0;
 157
 158  const Byte *buf = p->buf;
 159  UInt32 range = p->range;
 160  UInt32 code = p->code;
 161
 162  do
 163  {
 164    CLzmaProb *prob;
 165    UInt32 bound;
 166    unsigned ttt;
 167    unsigned posState = processedPos & pbMask;
 168
 169    prob = probs + IsMatch + (state << kNumPosBitsMax) + posState;
 170    IF_BIT_0(prob)
 171    {
 172      unsigned symbol;
 173      UPDATE_0(prob);
 174      prob = probs + Literal;
 175      if (checkDicSize != 0 || processedPos != 0)
 176        prob += (LZMA_LIT_SIZE * (((processedPos & lpMask) << lc) +
 177        (dic[(dicPos == 0 ? dicBufSize : dicPos) - 1] >> (8 - lc))));
 178
 179      if (state < kNumLitStates)
 180      {
 181        state -= (state < 4) ? state : 3;
 182        symbol = 1;
 183        #ifdef _LZMA_SIZE_OPT
 184        do { NORMAL_LITER_DEC } while (symbol < 0x100);
 185        #else
 186        NORMAL_LITER_DEC
 187        NORMAL_LITER_DEC
 188        NORMAL_LITER_DEC
 189        NORMAL_LITER_DEC
 190        NORMAL_LITER_DEC
 191        NORMAL_LITER_DEC
 192        NORMAL_LITER_DEC
 193        NORMAL_LITER_DEC
 194        #endif
 195      }
 196      else
 197      {
 198        unsigned matchByte = dic[(dicPos - rep0) + ((dicPos < rep0) ? dicBufSize : 0)];
 199        unsigned offs = 0x100;
 200        state -= (state < 10) ? 3 : 6;
 201        symbol = 1;
 202        #ifdef _LZMA_SIZE_OPT
 203        do
 204        {
 205          unsigned bit;
 206          CLzmaProb *probLit;
 207          MATCHED_LITER_DEC
 208        }
 209        while (symbol < 0x100);
 210        #else
 211        {
 212          unsigned bit;
 213          CLzmaProb *probLit;
 214          MATCHED_LITER_DEC
 215          MATCHED_LITER_DEC
 216          MATCHED_LITER_DEC
 217          MATCHED_LITER_DEC
 218          MATCHED_LITER_DEC
 219          MATCHED_LITER_DEC
 220          MATCHED_LITER_DEC
 221          MATCHED_LITER_DEC
 222        }
 223        #endif
 224      }
 225      dic[dicPos++] = (Byte)symbol;
 226      processedPos++;
 227      continue;
 228    }
 229    else
 230    {
 231      UPDATE_1(prob);
 232      prob = probs + IsRep + state;
 233      IF_BIT_0(prob)
 234      {
 235        UPDATE_0(prob);
 236        state += kNumStates;
 237        prob = probs + LenCoder;
 238      }
 239      else
 240      {
 241        UPDATE_1(prob);
 242        if (checkDicSize == 0 && processedPos == 0)
 243          return SZ_ERROR_DATA;
 244        prob = probs + IsRepG0 + state;
 245        IF_BIT_0(prob)
 246        {
 247          UPDATE_0(prob);
 248          prob = probs + IsRep0Long + (state << kNumPosBitsMax) + posState;
 249          IF_BIT_0(prob)
 250          {
 251            UPDATE_0(prob);
 252            dic[dicPos] = dic[(dicPos - rep0) + ((dicPos < rep0) ? dicBufSize : 0)];
 253            dicPos++;
 254            processedPos++;
 255            state = state < kNumLitStates ? 9 : 11;
 256            continue;
 257          }
 258          UPDATE_1(prob);
 259        }
 260        else
 261        {
 262          UInt32 distance;
 263          UPDATE_1(prob);
 264          prob = probs + IsRepG1 + state;
 265          IF_BIT_0(prob)
 266          {
 267            UPDATE_0(prob);
 268            distance = rep1;
 269          }
 270          else
 271          {
 272            UPDATE_1(prob);
 273            prob = probs + IsRepG2 + state;
 274            IF_BIT_0(prob)
 275            {
 276              UPDATE_0(prob);
 277              distance = rep2;
 278            }
 279            else
 280            {
 281              UPDATE_1(prob);
 282              distance = rep3;
 283              rep3 = rep2;
 284            }
 285            rep2 = rep1;
 286          }
 287          rep1 = rep0;
 288          rep0 = distance;
 289        }
 290        state = state < kNumLitStates ? 8 : 11;
 291        prob = probs + RepLenCoder;
 292      }
 293      {
 294        unsigned limit, offset;
 295        CLzmaProb *probLen = prob + LenChoice;
 296        IF_BIT_0(probLen)
 297        {
 298          UPDATE_0(probLen);
 299          probLen = prob + LenLow + (posState << kLenNumLowBits);
 300          offset = 0;
 301          limit = (1 << kLenNumLowBits);
 302        }
 303        else
 304        {
 305          UPDATE_1(probLen);
 306          probLen = prob + LenChoice2;
 307          IF_BIT_0(probLen)
 308          {
 309            UPDATE_0(probLen);
 310            probLen = prob + LenMid + (posState << kLenNumMidBits);
 311            offset = kLenNumLowSymbols;
 312            limit = (1 << kLenNumMidBits);
 313          }
 314          else
 315          {
 316            UPDATE_1(probLen);
 317            probLen = prob + LenHigh;
 318            offset = kLenNumLowSymbols + kLenNumMidSymbols;
 319            limit = (1 << kLenNumHighBits);
 320          }
 321        }
 322        TREE_DECODE(probLen, limit, len);
 323        len += offset;
 324      }
 325
 326      if (state >= kNumStates)
 327      {
 328        UInt32 distance;
 329        prob = probs + PosSlot +
 330            ((len < kNumLenToPosStates ? len : kNumLenToPosStates - 1) << kNumPosSlotBits);
 331        TREE_6_DECODE(prob, distance);
 332        if (distance >= kStartPosModelIndex)
 333        {
 334          unsigned posSlot = (unsigned)distance;
 335          int numDirectBits = (int)(((distance >> 1) - 1));
 336          distance = (2 | (distance & 1));
 337          if (posSlot < kEndPosModelIndex)
 338          {
 339            distance <<= numDirectBits;
 340            prob = probs + SpecPos + distance - posSlot - 1;
 341            {
 342              UInt32 mask = 1;
 343              unsigned i = 1;
 344              do
 345              {
 346                GET_BIT2(prob + i, i, ; , distance |= mask);
 347                mask <<= 1;
 348              }
 349              while (--numDirectBits != 0);
 350            }
 351          }
 352          else
 353          {
 354            numDirectBits -= kNumAlignBits;
 355            do
 356            {
 357              NORMALIZE
 358              range >>= 1;
 359              
 360              {
 361                UInt32 t;
 362                code -= range;
 363                t = (0 - ((UInt32)code >> 31)); /* (UInt32)((Int32)code >> 31) */
 364                distance = (distance << 1) + (t + 1);
 365                code += range & t;
 366              }
 367              /*
 368              distance <<= 1;
 369              if (code >= range)
 370              {
 371                code -= range;
 372                distance |= 1;
 373              }
 374              */
 375            }
 376            while (--numDirectBits != 0);
 377            prob = probs + Align;
 378            distance <<= kNumAlignBits;
 379            {
 380              unsigned i = 1;
 381              GET_BIT2(prob + i, i, ; , distance |= 1);
 382              GET_BIT2(prob + i, i, ; , distance |= 2);
 383              GET_BIT2(prob + i, i, ; , distance |= 4);
 384              GET_BIT2(prob + i, i, ; , distance |= 8);
 385            }
 386            if (distance == (UInt32)0xFFFFFFFF)
 387            {
 388              len += kMatchSpecLenStart;
 389              state -= kNumStates;
 390              break;
 391            }
 392          }
 393        }
 394        rep3 = rep2;
 395        rep2 = rep1;
 396        rep1 = rep0;
 397        rep0 = distance + 1;
 398        if (checkDicSize == 0)
 399        {
 400          if (distance >= processedPos)
 401            return SZ_ERROR_DATA;
 402        }
 403        else if (distance >= checkDicSize)
 404          return SZ_ERROR_DATA;
 405        state = (state < kNumStates + kNumLitStates) ? kNumLitStates : kNumLitStates + 3;
 406      }
 407
 408      len += kMatchMinLen;
 409
 410      if (limit == dicPos)
 411        return SZ_ERROR_DATA;
 412      {
 413        SizeT rem = limit - dicPos;
 414        unsigned curLen = ((rem < len) ? (unsigned)rem : len);
 415        SizeT pos = (dicPos - rep0) + ((dicPos < rep0) ? dicBufSize : 0);
 416
 417        processedPos += curLen;
 418
 419        len -= curLen;
 420        if (pos + curLen <= dicBufSize)
 421        {
 422          Byte *dest = dic + dicPos;
 423          ptrdiff_t src = (ptrdiff_t)pos - (ptrdiff_t)dicPos;
 424          const Byte *lim = dest + curLen;
 425          dicPos += curLen;
 426          do
 427            *(dest) = (Byte)*(dest + src);
 428          while (++dest != lim);
 429        }
 430        else
 431        {
 432          do
 433          {
 434            dic[dicPos++] = dic[pos];
 435            if (++pos == dicBufSize)
 436              pos = 0;
 437          }
 438          while (--curLen != 0);
 439        }
 440      }
 441    }
 442  }
 443  while (dicPos < limit && buf < bufLimit);
 444  NORMALIZE;
 445  p->buf = buf;
 446  p->range = range;
 447  p->code = code;
 448  p->remainLen = len;
 449  p->dicPos = dicPos;
 450  p->processedPos = processedPos;
 451  p->reps[0] = rep0;
 452  p->reps[1] = rep1;
 453  p->reps[2] = rep2;
 454  p->reps[3] = rep3;
 455  p->state = state;
 456
 457  return SZ_OK;
 458}
 459
 460static void MY_FAST_CALL LzmaDec_WriteRem(CLzmaDec *p, SizeT limit)
 461{
 462  if (p->remainLen != 0 && p->remainLen < kMatchSpecLenStart)
 463  {
 464    Byte *dic = p->dic;
 465    SizeT dicPos = p->dicPos;
 466    SizeT dicBufSize = p->dicBufSize;
 467    unsigned len = p->remainLen;
 468    UInt32 rep0 = p->reps[0];
 469    if (limit - dicPos < len)
 470      len = (unsigned)(limit - dicPos);
 471
 472    if (p->checkDicSize == 0 && p->prop.dicSize - p->processedPos <= len)
 473      p->checkDicSize = p->prop.dicSize;
 474
 475    p->processedPos += len;
 476    p->remainLen -= len;
 477    while (len != 0)
 478    {
 479      len--;
 480      dic[dicPos] = dic[(dicPos - rep0) + ((dicPos < rep0) ? dicBufSize : 0)];
 481      dicPos++;
 482    }
 483    p->dicPos = dicPos;
 484  }
 485}
 486
 487static int MY_FAST_CALL LzmaDec_DecodeReal2(CLzmaDec *p, SizeT limit, const Byte *bufLimit)
 488{
 489  do
 490  {
 491    SizeT limit2 = limit;
 492    if (p->checkDicSize == 0)
 493    {
 494      UInt32 rem = p->prop.dicSize - p->processedPos;
 495      if (limit - p->dicPos > rem)
 496        limit2 = p->dicPos + rem;
 497    }
 498    RINOK(LzmaDec_DecodeReal(p, limit2, bufLimit));
 499    if (p->processedPos >= p->prop.dicSize)
 500      p->checkDicSize = p->prop.dicSize;
 501    LzmaDec_WriteRem(p, limit);
 502  }
 503  while (p->dicPos < limit && p->buf < bufLimit && p->remainLen < kMatchSpecLenStart);
 504
 505  if (p->remainLen > kMatchSpecLenStart)
 506  {
 507    p->remainLen = kMatchSpecLenStart;
 508  }
 509  return 0;
 510}
 511
 512typedef enum
 513{
 514  DUMMY_ERROR, /* unexpected end of input stream */
 515  DUMMY_LIT,
 516  DUMMY_MATCH,
 517  DUMMY_REP
 518} ELzmaDummy;
 519
 520static ELzmaDummy LzmaDec_TryDummy(const CLzmaDec *p, const Byte *buf, SizeT inSize)
 521{
 522  UInt32 range = p->range;
 523  UInt32 code = p->code;
 524  const Byte *bufLimit = buf + inSize;
 525  CLzmaProb *probs = p->probs;
 526  unsigned state = p->state;
 527  ELzmaDummy res;
 528
 529  {
 530    CLzmaProb *prob;
 531    UInt32 bound;
 532    unsigned ttt;
 533    unsigned posState = (p->processedPos) & ((1 << p->prop.pb) - 1);
 534
 535    prob = probs + IsMatch + (state << kNumPosBitsMax) + posState;
 536    IF_BIT_0_CHECK(prob)
 537    {
 538      UPDATE_0_CHECK
 539
 540      /* if (bufLimit - buf >= 7) return DUMMY_LIT; */
 541
 542      prob = probs + Literal;
 543      if (p->checkDicSize != 0 || p->processedPos != 0)
 544        prob += (LZMA_LIT_SIZE *
 545          ((((p->processedPos) & ((1 << (p->prop.lp)) - 1)) << p->prop.lc) +
 546          (p->dic[(p->dicPos == 0 ? p->dicBufSize : p->dicPos) - 1] >> (8 - p->prop.lc))));
 547
 548      if (state < kNumLitStates)
 549      {
 550        unsigned symbol = 1;
 551        do { GET_BIT_CHECK(prob + symbol, symbol) } while (symbol < 0x100);
 552      }
 553      else
 554      {
 555        unsigned matchByte = p->dic[p->dicPos - p->reps[0] +
 556            ((p->dicPos < p->reps[0]) ? p->dicBufSize : 0)];
 557        unsigned offs = 0x100;
 558        unsigned symbol = 1;
 559        do
 560        {
 561          unsigned bit;
 562          CLzmaProb *probLit;
 563          matchByte <<= 1;
 564          bit = (matchByte & offs);
 565          probLit = prob + offs + bit + symbol;
 566          GET_BIT2_CHECK(probLit, symbol, offs &= ~bit, offs &= bit)
 567        }
 568        while (symbol < 0x100);
 569      }
 570      res = DUMMY_LIT;
 571    }
 572    else
 573    {
 574      unsigned len;
 575      UPDATE_1_CHECK;
 576
 577      prob = probs + IsRep + state;
 578      IF_BIT_0_CHECK(prob)
 579      {
 580        UPDATE_0_CHECK;
 581        state = 0;
 582        prob = probs + LenCoder;
 583        res = DUMMY_MATCH;
 584      }
 585      else
 586      {
 587        UPDATE_1_CHECK;
 588        res = DUMMY_REP;
 589        prob = probs + IsRepG0 + state;
 590        IF_BIT_0_CHECK(prob)
 591        {
 592          UPDATE_0_CHECK;
 593          prob = probs + IsRep0Long + (state << kNumPosBitsMax) + posState;
 594          IF_BIT_0_CHECK(prob)
 595          {
 596            UPDATE_0_CHECK;
 597            NORMALIZE_CHECK;
 598            return DUMMY_REP;
 599          }
 600          else
 601          {
 602            UPDATE_1_CHECK;
 603          }
 604        }
 605        else
 606        {
 607          UPDATE_1_CHECK;
 608          prob = probs + IsRepG1 + state;
 609          IF_BIT_0_CHECK(prob)
 610          {
 611            UPDATE_0_CHECK;
 612          }
 613          else
 614          {
 615            UPDATE_1_CHECK;
 616            prob = probs + IsRepG2 + state;
 617            IF_BIT_0_CHECK(prob)
 618            {
 619              UPDATE_0_CHECK;
 620            }
 621            else
 622            {
 623              UPDATE_1_CHECK;
 624            }
 625          }
 626        }
 627        state = kNumStates;
 628        prob = probs + RepLenCoder;
 629      }
 630      {
 631        unsigned limit, offset;
 632        CLzmaProb *probLen = prob + LenChoice;
 633        IF_BIT_0_CHECK(probLen)
 634        {
 635          UPDATE_0_CHECK;
 636          probLen = prob + LenLow + (posState << kLenNumLowBits);
 637          offset = 0;
 638          limit = 1 << kLenNumLowBits;
 639        }
 640        else
 641        {
 642          UPDATE_1_CHECK;
 643          probLen = prob + LenChoice2;
 644          IF_BIT_0_CHECK(probLen)
 645          {
 646            UPDATE_0_CHECK;
 647            probLen = prob + LenMid + (posState << kLenNumMidBits);
 648            offset = kLenNumLowSymbols;
 649            limit = 1 << kLenNumMidBits;
 650          }
 651          else
 652          {
 653            UPDATE_1_CHECK;
 654            probLen = prob + LenHigh;
 655            offset = kLenNumLowSymbols + kLenNumMidSymbols;
 656            limit = 1 << kLenNumHighBits;
 657          }
 658        }
 659        TREE_DECODE_CHECK(probLen, limit, len);
 660        len += offset;
 661      }
 662
 663      if (state < 4)
 664      {
 665        unsigned posSlot;
 666        prob = probs + PosSlot +
 667            ((len < kNumLenToPosStates ? len : kNumLenToPosStates - 1) <<
 668            kNumPosSlotBits);
 669        TREE_DECODE_CHECK(prob, 1 << kNumPosSlotBits, posSlot);
 670        if (posSlot >= kStartPosModelIndex)
 671        {
 672          int numDirectBits = ((posSlot >> 1) - 1);
 673
 674          /* if (bufLimit - buf >= 8) return DUMMY_MATCH; */
 675
 676          if (posSlot < kEndPosModelIndex)
 677          {
 678            prob = probs + SpecPos + ((2 | (posSlot & 1)) << numDirectBits) - posSlot - 1;
 679          }
 680          else
 681          {
 682            numDirectBits -= kNumAlignBits;
 683            do
 684            {
 685              NORMALIZE_CHECK
 686              range >>= 1;
 687              code -= range & (((code - range) >> 31) - 1);
 688              /* if (code >= range) code -= range; */
 689            }
 690            while (--numDirectBits != 0);
 691            prob = probs + Align;
 692            numDirectBits = kNumAlignBits;
 693          }
 694          {
 695            unsigned i = 1;
 696            do
 697            {
 698              GET_BIT_CHECK(prob + i, i);
 699            }
 700            while (--numDirectBits != 0);
 701          }
 702        }
 703      }
 704    }
 705  }
 706  NORMALIZE_CHECK;
 707  return res;
 708}
 709
 710
 711static void LzmaDec_InitRc(CLzmaDec *p, const Byte *data)
 712{
 713  p->code = ((UInt32)data[1] << 24) | ((UInt32)data[2] << 16) | ((UInt32)data[3] << 8) | ((UInt32)data[4]);
 714  p->range = 0xFFFFFFFF;
 715  p->needFlush = 0;
 716}
 717
 718void LzmaDec_InitDicAndState(CLzmaDec *p, Bool initDic, Bool initState)
 719{
 720  p->needFlush = 1;
 721  p->remainLen = 0;
 722  p->tempBufSize = 0;
 723
 724  if (initDic)
 725  {
 726    p->processedPos = 0;
 727    p->checkDicSize = 0;
 728    p->needInitState = 1;
 729  }
 730  if (initState)
 731    p->needInitState = 1;
 732}
 733
 734void LzmaDec_Init(CLzmaDec *p)
 735{
 736  p->dicPos = 0;
 737  LzmaDec_InitDicAndState(p, True, True);
 738}
 739
 740static void LzmaDec_InitStateReal(CLzmaDec *p)
 741{
 742  UInt32 numProbs = Literal + ((UInt32)LZMA_LIT_SIZE << (p->prop.lc + p->prop.lp));
 743  UInt32 i;
 744  CLzmaProb *probs = p->probs;
 745  for (i = 0; i < numProbs; i++)
 746    probs[i] = kBitModelTotal >> 1;
 747  p->reps[0] = p->reps[1] = p->reps[2] = p->reps[3] = 1;
 748  p->state = 0;
 749  p->needInitState = 0;
 750}
 751
 752SRes LzmaDec_DecodeToDic(CLzmaDec *p, SizeT dicLimit, const Byte *src, SizeT *srcLen,
 753    ELzmaFinishMode finishMode, ELzmaStatus *status)
 754{
 755  SizeT inSize = *srcLen;
 756  (*srcLen) = 0;
 757  LzmaDec_WriteRem(p, dicLimit);
 758  
 759  *status = LZMA_STATUS_NOT_SPECIFIED;
 760
 761  while (p->remainLen != kMatchSpecLenStart)
 762  {
 763      int checkEndMarkNow;
 764
 765      if (p->needFlush != 0)
 766      {
 767        for (; inSize > 0 && p->tempBufSize < RC_INIT_SIZE; (*srcLen)++, inSize--)
 768          p->tempBuf[p->tempBufSize++] = *src++;
 769        if (p->tempBufSize < RC_INIT_SIZE)
 770        {
 771          *status = LZMA_STATUS_NEEDS_MORE_INPUT;
 772          return SZ_OK;
 773        }
 774        if (p->tempBuf[0] != 0)
 775          return SZ_ERROR_DATA;
 776
 777        LzmaDec_InitRc(p, p->tempBuf);
 778        p->tempBufSize = 0;
 779      }
 780
 781      checkEndMarkNow = 0;
 782      if (p->dicPos >= dicLimit)
 783      {
 784        if (p->remainLen == 0 && p->code == 0)
 785        {
 786          *status = LZMA_STATUS_MAYBE_FINISHED_WITHOUT_MARK;
 787          return SZ_OK;
 788        }
 789        if (finishMode == LZMA_FINISH_ANY)
 790        {
 791          *status = LZMA_STATUS_NOT_FINISHED;
 792          return SZ_OK;
 793        }
 794        if (p->remainLen != 0)
 795        {
 796          *status = LZMA_STATUS_NOT_FINISHED;
 797          return SZ_ERROR_DATA;
 798        }
 799        checkEndMarkNow = 1;
 800      }
 801
 802      if (p->needInitState)
 803        LzmaDec_InitStateReal(p);
 804  
 805      if (p->tempBufSize == 0)
 806      {
 807        SizeT processed;
 808        const Byte *bufLimit;
 809        if (inSize < LZMA_REQUIRED_INPUT_MAX || checkEndMarkNow)
 810        {
 811          int dummyRes = LzmaDec_TryDummy(p, src, inSize);
 812          if (dummyRes == DUMMY_ERROR)
 813          {
 814            memcpy(p->tempBuf, src, inSize);
 815            p->tempBufSize = (unsigned)inSize;
 816            (*srcLen) += inSize;
 817            *status = LZMA_STATUS_NEEDS_MORE_INPUT;
 818            return SZ_OK;
 819          }
 820          if (checkEndMarkNow && dummyRes != DUMMY_MATCH)
 821          {
 822            *status = LZMA_STATUS_NOT_FINISHED;
 823            return SZ_ERROR_DATA;
 824          }
 825          bufLimit = src;
 826        }
 827        else
 828          bufLimit = src + inSize - LZMA_REQUIRED_INPUT_MAX;
 829        p->buf = src;
 830        if (LzmaDec_DecodeReal2(p, dicLimit, bufLimit) != 0)
 831          return SZ_ERROR_DATA;
 832        processed = (SizeT)(p->buf - src);
 833        (*srcLen) += processed;
 834        src += processed;
 835        inSize -= processed;
 836      }
 837      else
 838      {
 839        unsigned rem = p->tempBufSize, lookAhead = 0;
 840        while (rem < LZMA_REQUIRED_INPUT_MAX && lookAhead < inSize)
 841          p->tempBuf[rem++] = src[lookAhead++];
 842        p->tempBufSize = rem;
 843        if (rem < LZMA_REQUIRED_INPUT_MAX || checkEndMarkNow)
 844        {
 845          int dummyRes = LzmaDec_TryDummy(p, p->tempBuf, rem);
 846          if (dummyRes == DUMMY_ERROR)
 847          {
 848            (*srcLen) += lookAhead;
 849            *status = LZMA_STATUS_NEEDS_MORE_INPUT;
 850            return SZ_OK;
 851          }
 852          if (checkEndMarkNow && dummyRes != DUMMY_MATCH)
 853          {
 854            *status = LZMA_STATUS_NOT_FINISHED;
 855            return SZ_ERROR_DATA;
 856          }
 857        }
 858        p->buf = p->tempBuf;
 859        if (LzmaDec_DecodeReal2(p, dicLimit, p->buf) != 0)
 860          return SZ_ERROR_DATA;
 861        lookAhead -= (rem - (unsigned)(p->buf - p->tempBuf));
 862        (*srcLen) += lookAhead;
 863        src += lookAhead;
 864        inSize -= lookAhead;
 865        p->tempBufSize = 0;
 866      }
 867  }
 868  if (p->code == 0)
 869    *status = LZMA_STATUS_FINISHED_WITH_MARK;
 870  return (p->code == 0) ? SZ_OK : SZ_ERROR_DATA;
 871}
 872
 873SRes LzmaDec_DecodeToBuf(CLzmaDec *p, Byte *dest, SizeT *destLen, const Byte *src, SizeT *srcLen, ELzmaFinishMode finishMode, ELzmaStatus *status)
 874{
 875  SizeT outSize = *destLen;
 876  SizeT inSize = *srcLen;
 877  *srcLen = *destLen = 0;
 878  for (;;)
 879  {
 880    SizeT inSizeCur = inSize, outSizeCur, dicPos;
 881    ELzmaFinishMode curFinishMode;
 882    SRes res;
 883    if (p->dicPos == p->dicBufSize)
 884      p->dicPos = 0;
 885    dicPos = p->dicPos;
 886    if (outSize > p->dicBufSize - dicPos)
 887    {
 888      outSizeCur = p->dicBufSize;
 889      curFinishMode = LZMA_FINISH_ANY;
 890    }
 891    else
 892    {
 893      outSizeCur = dicPos + outSize;
 894      curFinishMode = finishMode;
 895    }
 896
 897    res = LzmaDec_DecodeToDic(p, outSizeCur, src, &inSizeCur, curFinishMode, status);
 898    src += inSizeCur;
 899    inSize -= inSizeCur;
 900    *srcLen += inSizeCur;
 901    outSizeCur = p->dicPos - dicPos;
 902    memcpy(dest, p->dic + dicPos, outSizeCur);
 903    dest += outSizeCur;
 904    outSize -= outSizeCur;
 905    *destLen += outSizeCur;
 906    if (res != 0)
 907      return res;
 908    if (outSizeCur == 0 || outSize == 0)
 909      return SZ_OK;
 910  }
 911}
 912
 913void LzmaDec_FreeProbs(CLzmaDec *p, ISzAlloc *alloc)
 914{
 915  alloc->Free(alloc, p->probs);
 916  p->probs = 0;
 917}
 918
 919static void LzmaDec_FreeDict(CLzmaDec *p, ISzAlloc *alloc)
 920{
 921  alloc->Free(alloc, p->dic);
 922  p->dic = 0;
 923}
 924
 925void LzmaDec_Free(CLzmaDec *p, ISzAlloc *alloc)
 926{
 927  LzmaDec_FreeProbs(p, alloc);
 928  LzmaDec_FreeDict(p, alloc);
 929}
 930
 931SRes LzmaProps_Decode(CLzmaProps *p, const Byte *data, unsigned size)
 932{
 933  UInt32 dicSize;
 934  Byte d;
 935  
 936  if (size < LZMA_PROPS_SIZE)
 937    return SZ_ERROR_UNSUPPORTED;
 938  else
 939    dicSize = data[1] | ((UInt32)data[2] << 8) | ((UInt32)data[3] << 16) | ((UInt32)data[4] << 24);
 940 
 941  if (dicSize < LZMA_DIC_MIN)
 942    dicSize = LZMA_DIC_MIN;
 943  p->dicSize = dicSize;
 944
 945  d = data[0];
 946  if (d >= (9 * 5 * 5))
 947    return SZ_ERROR_UNSUPPORTED;
 948
 949  p->lc = d % 9;
 950  d /= 9;
 951  p->pb = d / 5;
 952  p->lp = d % 5;
 953
 954  return SZ_OK;
 955}
 956
 957static SRes LzmaDec_AllocateProbs2(CLzmaDec *p, const CLzmaProps *propNew, ISzAlloc *alloc)
 958{
 959  UInt32 numProbs = LzmaProps_GetNumProbs(propNew);
 960  if (p->probs == 0 || numProbs != p->numProbs)
 961  {
 962    LzmaDec_FreeProbs(p, alloc);
 963    p->probs = (CLzmaProb *)alloc->Alloc(alloc, numProbs * sizeof(CLzmaProb));
 964    p->numProbs = numProbs;
 965    if (p->probs == 0)
 966      return SZ_ERROR_MEM;
 967  }
 968  return SZ_OK;
 969}
 970
 971SRes LzmaDec_AllocateProbs(CLzmaDec *p, const Byte *props, unsigned propsSize, ISzAlloc *alloc)
 972{
 973  CLzmaProps propNew;
 974  RINOK(LzmaProps_Decode(&propNew, props, propsSize));
 975  RINOK(LzmaDec_AllocateProbs2(p, &propNew, alloc));
 976  p->prop = propNew;
 977  return SZ_OK;
 978}
 979
 980SRes LzmaDec_Allocate(CLzmaDec *p, const Byte *props, unsigned propsSize, ISzAlloc *alloc)
 981{
 982  CLzmaProps propNew;
 983  SizeT dicBufSize;
 984  RINOK(LzmaProps_Decode(&propNew, props, propsSize));
 985  RINOK(LzmaDec_AllocateProbs2(p, &propNew, alloc));
 986  dicBufSize = propNew.dicSize;
 987  if (p->dic == 0 || dicBufSize != p->dicBufSize)
 988  {
 989    LzmaDec_FreeDict(p, alloc);
 990    p->dic = (Byte *)alloc->Alloc(alloc, dicBufSize);
 991    if (p->dic == 0)
 992    {
 993      LzmaDec_FreeProbs(p, alloc);
 994      return SZ_ERROR_MEM;
 995    }
 996  }
 997  p->dicBufSize = dicBufSize;
 998  p->prop = propNew;
 999  return SZ_OK;
1000}
1001
1002SRes LzmaDecode(Byte *dest, SizeT *destLen, const Byte *src, SizeT *srcLen,
1003    const Byte *propData, unsigned propSize, ELzmaFinishMode finishMode,
1004    ELzmaStatus *status, ISzAlloc *alloc)
1005{
1006  CLzmaDec p;
1007  SRes res;
1008  SizeT outSize = *destLen, inSize = *srcLen;
1009  *destLen = *srcLen = 0;
1010  *status = LZMA_STATUS_NOT_SPECIFIED;
1011  if (inSize < RC_INIT_SIZE)
1012    return SZ_ERROR_INPUT_EOF;
1013  LzmaDec_Construct(&p);
1014  RINOK(LzmaDec_AllocateProbs(&p, propData, propSize, alloc));
1015  p.dic = dest;
1016  p.dicBufSize = outSize;
1017  LzmaDec_Init(&p);
1018  *srcLen = inSize;
1019  res = LzmaDec_DecodeToDic(&p, outSize, src, srcLen, finishMode, status);
1020  *destLen = p.dicPos;
1021  if (res == SZ_OK && *status == LZMA_STATUS_NEEDS_MORE_INPUT)
1022    res = SZ_ERROR_INPUT_EOF;
1023  LzmaDec_FreeProbs(&p, alloc);
1024  return res;
1025}