BaseTools/Source/C/LzmaCompress/Sdk/C/LzmaDec.c

   1 /* LzmaDec.c -- LZMA Decoder
   2 2018-02-28 : Igor Pavlov : Public domain */
   3
   4 #include "Precomp.h"
   5
   6 /* #include "CpuArch.h" */
   7 #include "LzmaDec.h"
   8
   9 #include <string.h>
  10
  11 #define kNumTopBits 24
  12 #define kTopValue ((UInt32)1 << kNumTopBits)
  13
  14 #define kNumBitModelTotalBits 11
  15 #define kBitModelTotal (1 << kNumBitModelTotalBits)
  16 #define kNumMoveBits 5
  17
  18 #define RC_INIT_SIZE 5
  19
  20 #define NORMALIZE if (range < kTopValue) { range <<= 8; code = (code << 8) | (*buf++); }
  21
  22 #define IF_BIT_0(p) ttt = *(p); NORMALIZE; bound = (range >> kNumBitModelTotalBits) * ttt; if (code < bound)
  23 #define UPDATE_0(p) range = bound; *(p) = (CLzmaProb)(ttt + ((kBitModelTotal - ttt) >> kNumMoveBits));
  24 #define UPDATE_1(p) range -= bound; code -= bound; *(p) = (CLzmaProb)(ttt - (ttt >> kNumMoveBits));
  25 #define GET_BIT2(p, i, A0, A1) IF_BIT_0(p) \
  26   { UPDATE_0(p); i = (i + i); A0; } else \
  27   { UPDATE_1(p); i = (i + i) + 1; A1; }
  28
  29 #define TREE_GET_BIT(probs, i) { GET_BIT2(probs + i, i, ;, ;); }
  30
  31 #define REV_BIT(p, i, A0, A1) IF_BIT_0(p + i) \
  32   { UPDATE_0(p + i); A0; } else \
  33   { UPDATE_1(p + i); A1; }
  34 #define REV_BIT_VAR(  p, i, m) REV_BIT(p, i, i += m; m += m, m += m; i += m; )
  35 #define REV_BIT_CONST(p, i, m) REV_BIT(p, i, i += m;       , i += m * 2; )
  36 #define REV_BIT_LAST( p, i, m) REV_BIT(p, i, i -= m        , ; )
  37
  38 #define TREE_DECODE(probs, limit, i) \
  39   { i = 1; do { TREE_GET_BIT(probs, i); } while (i < limit); i -= limit; }
  40
  41 /* #define _LZMA_SIZE_OPT */
  42
  43 #ifdef _LZMA_SIZE_OPT
  44 #define TREE_6_DECODE(probs, i) TREE_DECODE(probs, (1 << 6), i)
  45 #else
  46 #define TREE_6_DECODE(probs, i) \
  47   { i = 1; \
  48   TREE_GET_BIT(probs, i); \
  49   TREE_GET_BIT(probs, i); \
  50   TREE_GET_BIT(probs, i); \
  51   TREE_GET_BIT(probs, i); \
  52   TREE_GET_BIT(probs, i); \
  53   TREE_GET_BIT(probs, i); \
  54   i -= 0x40; }
  55 #endif
  56
  57 #define NORMAL_LITER_DEC TREE_GET_BIT(prob, symbol)
  58 #define MATCHED_LITER_DEC \
  59   matchByte += matchByte; \
  60   bit = offs; \
  61   offs &= matchByte; \
  62   probLit = prob + (offs + bit + symbol); \
  63   GET_BIT2(probLit, symbol, offs ^= bit; , ;)
  64
  65
  66
  67 #define NORMALIZE_CHECK if (range < kTopValue) { if (buf >= bufLimit) return DUMMY_ERROR; range <<= 8; code = (code << 8) | (*buf++); }
  68
  69 #define IF_BIT_0_CHECK(p) ttt = *(p); NORMALIZE_CHECK; bound = (range >> kNumBitModelTotalBits) * ttt; if (code < bound)
  70 #define UPDATE_0_CHECK range = bound;
  71 #define UPDATE_1_CHECK range -= bound; code -= bound;
  72 #define GET_BIT2_CHECK(p, i, A0, A1) IF_BIT_0_CHECK(p) \
  73   { UPDATE_0_CHECK; i = (i + i); A0; } else \
  74   { UPDATE_1_CHECK; i = (i + i) + 1; A1; }
  75 #define GET_BIT_CHECK(p, i) GET_BIT2_CHECK(p, i, ; , ;)
  76 #define TREE_DECODE_CHECK(probs, limit, i) \
  77   { i = 1; do { GET_BIT_CHECK(probs + i, i) } while (i < limit); i -= limit; }
  78
  79
  80 #define REV_BIT_CHECK(p, i, m) IF_BIT_0_CHECK(p + i) \
  81   { UPDATE_0_CHECK; i += m; m += m; } else \
  82   { UPDATE_1_CHECK; m += m; i += m; }
  83
  84
  85 #define kNumPosBitsMax 4
  86 #define kNumPosStatesMax (1 << kNumPosBitsMax)
  87
  88 #define kLenNumLowBits 3
  89 #define kLenNumLowSymbols (1 << kLenNumLowBits)
  90 #define kLenNumHighBits 8
  91 #define kLenNumHighSymbols (1 << kLenNumHighBits)
  92
  93 #define LenLow 0
  94 #define LenHigh (LenLow + 2 * (kNumPosStatesMax << kLenNumLowBits))
  95 #define kNumLenProbs (LenHigh + kLenNumHighSymbols)
  96
  97 #define LenChoice LenLow
  98 #define LenChoice2 (LenLow + (1 << kLenNumLowBits))
  99
 100 #define kNumStates 12
 101 #define kNumStates2 16
 102 #define kNumLitStates 7
 103
 104 #define kStartPosModelIndex 4
 105 #define kEndPosModelIndex 14
 106 #define kNumFullDistances (1 << (kEndPosModelIndex >> 1))
 107
 108 #define kNumPosSlotBits 6
 109 #define kNumLenToPosStates 4
 110
 111 #define kNumAlignBits 4
 112 #define kAlignTableSize (1 << kNumAlignBits)
 113
 114 #define kMatchMinLen 2
 115 #define kMatchSpecLenStart (kMatchMinLen + kLenNumLowSymbols * 2 + kLenNumHighSymbols)
 116
 117 /* External ASM code needs same CLzmaProb array layout. So don't change it. */
 118
 119 /* (probs_1664) is faster and better for code size at some platforms */
 120 /*
 121 #ifdef MY_CPU_X86_OR_AMD64
 122 */
 123 #define kStartOffset 1664
 124 #define GET_PROBS p->probs_1664
 125 /*
 126 #define GET_PROBS p->probs + kStartOffset
 127 #else
 128 #define kStartOffset 0
 129 #define GET_PROBS p->probs
 130 #endif
 131 */
 132
 133 #define SpecPos (-kStartOffset)
 134 #define IsRep0Long (SpecPos + kNumFullDistances)
 135 #define RepLenCoder (IsRep0Long + (kNumStates2 << kNumPosBitsMax))
 136 #define LenCoder (RepLenCoder + kNumLenProbs)
 137 #define IsMatch (LenCoder + kNumLenProbs)
 138 #define Align (IsMatch + (kNumStates2 << kNumPosBitsMax))
 139 #define IsRep (Align + kAlignTableSize)
 140 #define IsRepG0 (IsRep + kNumStates)
 141 #define IsRepG1 (IsRepG0 + kNumStates)
 142 #define IsRepG2 (IsRepG1 + kNumStates)
 143 #define PosSlot (IsRepG2 + kNumStates)
 144 #define Literal (PosSlot + (kNumLenToPosStates << kNumPosSlotBits))
 145 #define NUM_BASE_PROBS (Literal + kStartOffset)
 146
 147 #if Align != 0 && kStartOffset != 0
 148   #error Stop_Compiling_Bad_LZMA_kAlign
 149 #endif
 150
 151 #if NUM_BASE_PROBS != 1984
 152   #error Stop_Compiling_Bad_LZMA_PROBS
 153 #endif
 154
 155
 156 #define LZMA_LIT_SIZE 0x300
 157
 158 #define LzmaProps_GetNumProbs(p) (NUM_BASE_PROBS + ((UInt32)LZMA_LIT_SIZE << ((p)->lc + (p)->lp)))
 159
 160
 161 #define CALC_POS_STATE(processedPos, pbMask) (((processedPos) & (pbMask)) << 4)
 162 #define COMBINED_PS_STATE (posState + state)
 163 #define GET_LEN_STATE (posState)
 164
 165 #define LZMA_DIC_MIN (1 << 12)
 166
 167 /*
 168 p->remainLen : shows status of LZMA decoder:
 169     < kMatchSpecLenStart : normal remain
 170     = kMatchSpecLenStart : finished
 171     = kMatchSpecLenStart + 1 : need init range coder
 172     = kMatchSpecLenStart + 2 : need init range coder and state
 173 */
 174
 175 /* ---------- LZMA_DECODE_REAL ---------- */
 176 /*
 177 LzmaDec_DecodeReal_3() can be implemented in external ASM file.
 178 3 - is the code compatibility version of that function for check at link time.
 179 */
 180
 181 #define LZMA_DECODE_REAL LzmaDec_DecodeReal_3
 182
 183 /*
 184 LZMA_DECODE_REAL()
 185 In:
 186   RangeCoder is normalized
 187   if (p->dicPos == limit)
 188   {
 189     LzmaDec_TryDummy() was called before to exclude LITERAL and MATCH-REP cases.
 190     So first symbol can be only MATCH-NON-REP. And if that MATCH-NON-REP symbol
 191     is not END_OF_PAYALOAD_MARKER, then function returns error code.
 192   }
 193
 194 Processing:
 195   first LZMA symbol will be decoded in any case
 196   All checks for limits are at the end of main loop,
 197   It will decode new LZMA-symbols while (p->buf < bufLimit && dicPos < limit),
 198   RangeCoder is still without last normalization when (p->buf < bufLimit) is being checked.
 199
 200 Out:
 201   RangeCoder is normalized
 202   Result:
 203     SZ_OK - OK
 204     SZ_ERROR_DATA - Error
 205   p->remainLen:
 206     < kMatchSpecLenStart : normal remain
 207     = kMatchSpecLenStart : finished
 208 */
 209
 210
 211 #ifdef _LZMA_DEC_OPT
 212
 213 int MY_FAST_CALL LZMA_DECODE_REAL(CLzmaDec *p, SizeT limit, const Byte *bufLimit);
 214
 215 #else
 216
 217 static
 218 int MY_FAST_CALL LZMA_DECODE_REAL(CLzmaDec *p, SizeT limit, const Byte *bufLimit)
 219 {
 220   CLzmaProb *probs = GET_PROBS;
 221   unsigned state = (unsigned)p->state;
 222   UInt32 rep0 = p->reps[0], rep1 = p->reps[1], rep2 = p->reps[2], rep3 = p->reps[3];
 223   unsigned pbMask = ((unsigned)1 << (p->prop.pb)) - 1;
 224   unsigned lc = p->prop.lc;
 225   unsigned lpMask = ((unsigned)0x100 << p->prop.lp) - ((unsigned)0x100 >> lc);
 226
 227   Byte *dic = p->dic;
 228   SizeT dicBufSize = p->dicBufSize;
 229   SizeT dicPos = p->dicPos;
 230
 231   UInt32 processedPos = p->processedPos;
 232   UInt32 checkDicSize = p->checkDicSize;
 233   unsigned len = 0;
 234
 235   const Byte *buf = p->buf;
 236   UInt32 range = p->range;
 237   UInt32 code = p->code;
 238
 239   do
 240   {
 241     CLzmaProb *prob;
 242     UInt32 bound;
 243     unsigned ttt;
 244     unsigned posState = CALC_POS_STATE(processedPos, pbMask);
 245
 246     prob = probs + IsMatch + COMBINED_PS_STATE;
 247     IF_BIT_0(prob)
 248     {
 249       unsigned symbol;
 250       UPDATE_0(prob);
 251       prob = probs + Literal;
 252       if (processedPos != 0 || checkDicSize != 0)
 253         prob += (UInt32)3 * ((((processedPos << 8) + dic[(dicPos == 0 ? dicBufSize : dicPos) - 1]) & lpMask) << lc);
 254       processedPos++;
 255
 256       if (state < kNumLitStates)
 257       {
 258         state -= (state < 4) ? state : 3;
 259         symbol = 1;
 260         #ifdef _LZMA_SIZE_OPT
 261         do { NORMAL_LITER_DEC } while (symbol < 0x100);
 262         #else
 263         NORMAL_LITER_DEC
 264         NORMAL_LITER_DEC
 265         NORMAL_LITER_DEC
 266         NORMAL_LITER_DEC
 267         NORMAL_LITER_DEC
 268         NORMAL_LITER_DEC
 269         NORMAL_LITER_DEC
 270         NORMAL_LITER_DEC
 271         #endif
 272       }
 273       else
 274       {
 275         unsigned matchByte = dic[dicPos - rep0 + (dicPos < rep0 ? dicBufSize : 0)];
 276         unsigned offs = 0x100;
 277         state -= (state < 10) ? 3 : 6;
 278         symbol = 1;
 279         #ifdef _LZMA_SIZE_OPT
 280         do
 281         {
 282           unsigned bit;
 283           CLzmaProb *probLit;
 284           MATCHED_LITER_DEC
 285         }
 286         while (symbol < 0x100);
 287         #else
 288         {
 289           unsigned bit;
 290           CLzmaProb *probLit;
 291           MATCHED_LITER_DEC
 292           MATCHED_LITER_DEC
 293           MATCHED_LITER_DEC
 294           MATCHED_LITER_DEC
 295           MATCHED_LITER_DEC
 296           MATCHED_LITER_DEC
 297           MATCHED_LITER_DEC
 298           MATCHED_LITER_DEC
 299         }
 300         #endif
 301       }
 302
 303       dic[dicPos++] = (Byte)symbol;
 304       continue;
 305     }
 306
 307     {
 308       UPDATE_1(prob);
 309       prob = probs + IsRep + state;
 310       IF_BIT_0(prob)
 311       {
 312         UPDATE_0(prob);
 313         state += kNumStates;
 314         prob = probs + LenCoder;
 315       }
 316       else
 317       {
 318         UPDATE_1(prob);
 319         /*
 320         // that case was checked before with kBadRepCode
 321         if (checkDicSize == 0 && processedPos == 0)
 322           return SZ_ERROR_DATA;
 323         */
 324         prob = probs + IsRepG0 + state;
 325         IF_BIT_0(prob)
 326         {
 327           UPDATE_0(prob);
 328           prob = probs + IsRep0Long + COMBINED_PS_STATE;
 329           IF_BIT_0(prob)
 330           {
 331             UPDATE_0(prob);
 332             dic[dicPos] = dic[dicPos - rep0 + (dicPos < rep0 ? dicBufSize : 0)];
 333             dicPos++;
 334             processedPos++;
 335             state = state < kNumLitStates ? 9 : 11;
 336             continue;
 337           }
 338           UPDATE_1(prob);
 339         }
 340         else
 341         {
 342           UInt32 distance;
 343           UPDATE_1(prob);
 344           prob = probs + IsRepG1 + state;
 345           IF_BIT_0(prob)
 346           {
 347             UPDATE_0(prob);
 348             distance = rep1;
 349           }
 350           else
 351           {
 352             UPDATE_1(prob);
 353             prob = probs + IsRepG2 + state;
 354             IF_BIT_0(prob)
 355             {
 356               UPDATE_0(prob);
 357               distance = rep2;
 358             }
 359             else
 360             {
 361               UPDATE_1(prob);
 362               distance = rep3;
 363               rep3 = rep2;
 364             }
 365             rep2 = rep1;
 366           }
 367           rep1 = rep0;
 368           rep0 = distance;
 369         }
 370         state = state < kNumLitStates ? 8 : 11;
 371         prob = probs + RepLenCoder;
 372       }
 373
 374       #ifdef _LZMA_SIZE_OPT
 375       {
 376         unsigned lim, offset;
 377         CLzmaProb *probLen = prob + LenChoice;
 378         IF_BIT_0(probLen)
 379         {
 380           UPDATE_0(probLen);
 381           probLen = prob + LenLow + GET_LEN_STATE;
 382           offset = 0;
 383           lim = (1 << kLenNumLowBits);
 384         }
 385         else
 386         {
 387           UPDATE_1(probLen);
 388           probLen = prob + LenChoice2;
 389           IF_BIT_0(probLen)
 390           {
 391             UPDATE_0(probLen);
 392             probLen = prob + LenLow + GET_LEN_STATE + (1 << kLenNumLowBits);
 393             offset = kLenNumLowSymbols;
 394             lim = (1 << kLenNumLowBits);
 395           }
 396           else
 397           {
 398             UPDATE_1(probLen);
 399             probLen = prob + LenHigh;
 400             offset = kLenNumLowSymbols * 2;
 401             lim = (1 << kLenNumHighBits);
 402           }
 403         }
 404         TREE_DECODE(probLen, lim, len);
 405         len += offset;
 406       }
 407       #else
 408       {
 409         CLzmaProb *probLen = prob + LenChoice;
 410         IF_BIT_0(probLen)
 411         {
 412           UPDATE_0(probLen);
 413           probLen = prob + LenLow + GET_LEN_STATE;
 414           len = 1;
 415           TREE_GET_BIT(probLen, len);
 416           TREE_GET_BIT(probLen, len);
 417           TREE_GET_BIT(probLen, len);
 418           len -= 8;
 419         }
 420         else
 421         {
 422           UPDATE_1(probLen);
 423           probLen = prob + LenChoice2;
 424           IF_BIT_0(probLen)
 425           {
 426             UPDATE_0(probLen);
 427             probLen = prob + LenLow + GET_LEN_STATE + (1 << kLenNumLowBits);
 428             len = 1;
 429             TREE_GET_BIT(probLen, len);
 430             TREE_GET_BIT(probLen, len);
 431             TREE_GET_BIT(probLen, len);
 432           }
 433           else
 434           {
 435             UPDATE_1(probLen);
 436             probLen = prob + LenHigh;
 437             TREE_DECODE(probLen, (1 << kLenNumHighBits), len);
 438             len += kLenNumLowSymbols * 2;
 439           }
 440         }
 441       }
 442       #endif
 443
 444       if (state >= kNumStates)
 445       {
 446         UInt32 distance;
 447         prob = probs + PosSlot +
 448             ((len < kNumLenToPosStates ? len : kNumLenToPosStates - 1) << kNumPosSlotBits);
 449         TREE_6_DECODE(prob, distance);
 450         if (distance >= kStartPosModelIndex)
 451         {
 452           unsigned posSlot = (unsigned)distance;
 453           unsigned numDirectBits = (unsigned)(((distance >> 1) - 1));
 454           distance = (2 | (distance & 1));
 455           if (posSlot < kEndPosModelIndex)
 456           {
 457             distance <<= numDirectBits;
 458             prob = probs + SpecPos;
 459             {
 460               UInt32 m = 1;
 461               distance++;
 462               do
 463               {
 464                 REV_BIT_VAR(prob, distance, m);
 465               }
 466               while (--numDirectBits);
 467               distance -= m;
 468             }
 469           }
 470           else
 471           {
 472             numDirectBits -= kNumAlignBits;
 473             do
 474             {
 475               NORMALIZE
 476               range >>= 1;
 477
 478               {
 479                 UInt32 t;
 480                 code -= range;
 481                 t = (0 - ((UInt32)code >> 31)); /* (UInt32)((Int32)code >> 31) */
 482                 distance = (distance << 1) + (t + 1);
 483                 code += range & t;
 484               }
 485               /*
 486               distance <<= 1;
 487               if (code >= range)
 488               {
 489                 code -= range;
 490                 distance |= 1;
 491               }
 492               */
 493             }
 494             while (--numDirectBits);
 495             prob = probs + Align;
 496             distance <<= kNumAlignBits;
 497             {
 498               unsigned i = 1;
 499               REV_BIT_CONST(prob, i, 1);
 500               REV_BIT_CONST(prob, i, 2);
 501               REV_BIT_CONST(prob, i, 4);
 502               REV_BIT_LAST (prob, i, 8);
 503               distance |= i;
 504             }
 505             if (distance == (UInt32)0xFFFFFFFF)
 506             {
 507               len = kMatchSpecLenStart;
 508               state -= kNumStates;
 509               break;
 510             }
 511           }
 512         }
 513
 514         rep3 = rep2;
 515         rep2 = rep1;
 516         rep1 = rep0;
 517         rep0 = distance + 1;
 518         state = (state < kNumStates + kNumLitStates) ? kNumLitStates : kNumLitStates + 3;
 519         if (distance >= (checkDicSize == 0 ? processedPos: checkDicSize))
 520         {
 521           p->dicPos = dicPos;
 522           return SZ_ERROR_DATA;
 523         }
 524       }
 525
 526       len += kMatchMinLen;
 527
 528       {
 529         SizeT rem;
 530         unsigned curLen;
 531         SizeT pos;
 532
 533         if ((rem = limit - dicPos) == 0)
 534         {
 535           p->dicPos = dicPos;
 536           return SZ_ERROR_DATA;
 537         }
 538
 539         curLen = ((rem < len) ? (unsigned)rem : len);
 540         pos = dicPos - rep0 + (dicPos < rep0 ? dicBufSize : 0);
 541
 542         processedPos += curLen;
 543
 544         len -= curLen;
 545         if (curLen <= dicBufSize - pos)
 546         {
 547           Byte *dest = dic + dicPos;
 548           ptrdiff_t src = (ptrdiff_t)pos - (ptrdiff_t)dicPos;
 549           const Byte *lim = dest + curLen;
 550           dicPos += curLen;
 551           do
 552             *(dest) = (Byte)*(dest + src);
 553           while (++dest != lim);
 554         }
 555         else
 556         {
 557           do
 558           {
 559             dic[dicPos++] = dic[pos];
 560             if (++pos == dicBufSize)
 561               pos = 0;
 562           }
 563           while (--curLen != 0);
 564         }
 565       }
 566     }
 567   }
 568   while (dicPos < limit && buf < bufLimit);
 569
 570   NORMALIZE;
 571
 572   p->buf = buf;
 573   p->range = range;
 574   p->code = code;
 575   p->remainLen = len;
 576   p->dicPos = dicPos;
 577   p->processedPos = processedPos;
 578   p->reps[0] = rep0;
 579   p->reps[1] = rep1;
 580   p->reps[2] = rep2;
 581   p->reps[3] = rep3;
 582   p->state = state;
 583
 584   return SZ_OK;
 585 }
 586 #endif
 587
 588 static void MY_FAST_CALL LzmaDec_WriteRem(CLzmaDec *p, SizeT limit)
 589 {
 590   if (p->remainLen != 0 && p->remainLen < kMatchSpecLenStart)
 591   {
 592     Byte *dic = p->dic;
 593     SizeT dicPos = p->dicPos;
 594     SizeT dicBufSize = p->dicBufSize;
 595     unsigned len = (unsigned)p->remainLen;
 596     SizeT rep0 = p->reps[0]; /* we use SizeT to avoid the BUG of VC14 for AMD64 */
 597     SizeT rem = limit - dicPos;
 598     if (rem < len)
 599       len = (unsigned)(rem);
 600
 601     if (p->checkDicSize == 0 && p->prop.dicSize - p->processedPos <= len)
 602       p->checkDicSize = p->prop.dicSize;
 603
 604     p->processedPos += len;
 605     p->remainLen -= len;
 606     while (len != 0)
 607     {
 608       len--;
 609       dic[dicPos] = dic[dicPos - rep0 + (dicPos < rep0 ? dicBufSize : 0)];
 610       dicPos++;
 611     }
 612     p->dicPos = dicPos;
 613   }
 614 }
 615
 616
 617 #define kRange0 0xFFFFFFFF
 618 #define kBound0 ((kRange0 >> kNumBitModelTotalBits) << (kNumBitModelTotalBits - 1))
 619 #define kBadRepCode (kBound0 + (((kRange0 - kBound0) >> kNumBitModelTotalBits) << (kNumBitModelTotalBits - 1)))
 620 #if kBadRepCode != (0xC0000000 - 0x400)
 621   #error Stop_Compiling_Bad_LZMA_Check
 622 #endif
 623
 624 static int MY_FAST_CALL LzmaDec_DecodeReal2(CLzmaDec *p, SizeT limit, const Byte *bufLimit)
 625 {
 626   do
 627   {
 628     SizeT limit2 = limit;
 629     if (p->checkDicSize == 0)
 630     {
 631       UInt32 rem = p->prop.dicSize - p->processedPos;
 632       if (limit - p->dicPos > rem)
 633         limit2 = p->dicPos + rem;
 634
 635       if (p->processedPos == 0)
 636         if (p->code >= kBadRepCode)
 637           return SZ_ERROR_DATA;
 638     }
 639
 640     RINOK(LZMA_DECODE_REAL(p, limit2, bufLimit));
 641
 642     if (p->checkDicSize == 0 && p->processedPos >= p->prop.dicSize)
 643       p->checkDicSize = p->prop.dicSize;
 644
 645     LzmaDec_WriteRem(p, limit);
 646   }
 647   while (p->dicPos < limit && p->buf < bufLimit && p->remainLen < kMatchSpecLenStart);
 648
 649   return 0;
 650 }
 651
 652 typedef enum
 653 {
 654   DUMMY_ERROR, /* unexpected end of input stream */
 655   DUMMY_LIT,
 656   DUMMY_MATCH,
 657   DUMMY_REP
 658 } ELzmaDummy;
 659
 660 static ELzmaDummy LzmaDec_TryDummy(const CLzmaDec *p, const Byte *buf, SizeT inSize)
 661 {
 662   UInt32 range = p->range;
 663   UInt32 code = p->code;
 664   const Byte *bufLimit = buf + inSize;
 665   const CLzmaProb *probs = GET_PROBS;
 666   unsigned state = (unsigned)p->state;
 667   ELzmaDummy res;
 668
 669   {
 670     const CLzmaProb *prob;
 671     UInt32 bound;
 672     unsigned ttt;
 673     unsigned posState = CALC_POS_STATE(p->processedPos, (1 << p->prop.pb) - 1);
 674
 675     prob = probs + IsMatch + COMBINED_PS_STATE;
 676     IF_BIT_0_CHECK(prob)
 677     {
 678       UPDATE_0_CHECK
 679
 680       /* if (bufLimit - buf >= 7) return DUMMY_LIT; */
 681
 682       prob = probs + Literal;
 683       if (p->checkDicSize != 0 || p->processedPos != 0)
 684         prob += ((UInt32)LZMA_LIT_SIZE *
 685             ((((p->processedPos) & ((1 << (p->prop.lp)) - 1)) << p->prop.lc) +
 686             (p->dic[(p->dicPos == 0 ? p->dicBufSize : p->dicPos) - 1] >> (8 - p->prop.lc))));
 687
 688       if (state < kNumLitStates)
 689       {
 690         unsigned symbol = 1;
 691         do { GET_BIT_CHECK(prob + symbol, symbol) } while (symbol < 0x100);
 692       }
 693       else
 694       {
 695         unsigned matchByte = p->dic[p->dicPos - p->reps[0] +
 696             (p->dicPos < p->reps[0] ? p->dicBufSize : 0)];
 697         unsigned offs = 0x100;
 698         unsigned symbol = 1;
 699         do
 700         {
 701           unsigned bit;
 702           const CLzmaProb *probLit;
 703           matchByte += matchByte;
 704           bit = offs;
 705           offs &= matchByte;
 706           probLit = prob + (offs + bit + symbol);
 707           GET_BIT2_CHECK(probLit, symbol, offs ^= bit; , ; )
 708         }
 709         while (symbol < 0x100);
 710       }
 711       res = DUMMY_LIT;
 712     }
 713     else
 714     {
 715       unsigned len;
 716       UPDATE_1_CHECK;
 717
 718       prob = probs + IsRep + state;
 719       IF_BIT_0_CHECK(prob)
 720       {
 721         UPDATE_0_CHECK;
 722         state = 0;
 723         prob = probs + LenCoder;
 724         res = DUMMY_MATCH;
 725       }
 726       else
 727       {
 728         UPDATE_1_CHECK;
 729         res = DUMMY_REP;
 730         prob = probs + IsRepG0 + state;
 731         IF_BIT_0_CHECK(prob)
 732         {
 733           UPDATE_0_CHECK;
 734           prob = probs + IsRep0Long + COMBINED_PS_STATE;
 735           IF_BIT_0_CHECK(prob)
 736           {
 737             UPDATE_0_CHECK;
 738             NORMALIZE_CHECK;
 739             return DUMMY_REP;
 740           }
 741           else
 742           {
 743             UPDATE_1_CHECK;
 744           }
 745         }
 746         else
 747         {
 748           UPDATE_1_CHECK;
 749           prob = probs + IsRepG1 + state;
 750           IF_BIT_0_CHECK(prob)
 751           {
 752             UPDATE_0_CHECK;
 753           }
 754           else
 755           {
 756             UPDATE_1_CHECK;
 757             prob = probs + IsRepG2 + state;
 758             IF_BIT_0_CHECK(prob)
 759             {
 760               UPDATE_0_CHECK;
 761             }
 762             else
 763             {
 764               UPDATE_1_CHECK;
 765             }
 766           }
 767         }
 768         state = kNumStates;
 769         prob = probs + RepLenCoder;
 770       }
 771       {
 772         unsigned limit, offset;
 773         const CLzmaProb *probLen = prob + LenChoice;
 774         IF_BIT_0_CHECK(probLen)
 775         {
 776           UPDATE_0_CHECK;
 777           probLen = prob + LenLow + GET_LEN_STATE;
 778           offset = 0;
 779           limit = 1 << kLenNumLowBits;
 780         }
 781         else
 782         {
 783           UPDATE_1_CHECK;
 784           probLen = prob + LenChoice2;
 785           IF_BIT_0_CHECK(probLen)
 786           {
 787             UPDATE_0_CHECK;
 788             probLen = prob + LenLow + GET_LEN_STATE + (1 << kLenNumLowBits);
 789             offset = kLenNumLowSymbols;
 790             limit = 1 << kLenNumLowBits;
 791           }
 792           else
 793           {
 794             UPDATE_1_CHECK;
 795             probLen = prob + LenHigh;
 796             offset = kLenNumLowSymbols * 2;
 797             limit = 1 << kLenNumHighBits;
 798           }
 799         }
 800         TREE_DECODE_CHECK(probLen, limit, len);
 801         len += offset;
 802       }
 803
 804       if (state < 4)
 805       {
 806         unsigned posSlot;
 807         prob = probs + PosSlot +
 808             ((len < kNumLenToPosStates - 1 ? len : kNumLenToPosStates - 1) <<
 809             kNumPosSlotBits);
 810         TREE_DECODE_CHECK(prob, 1 << kNumPosSlotBits, posSlot);
 811         if (posSlot >= kStartPosModelIndex)
 812         {
 813           unsigned numDirectBits = ((posSlot >> 1) - 1);
 814
 815           /* if (bufLimit - buf >= 8) return DUMMY_MATCH; */
 816
 817           if (posSlot < kEndPosModelIndex)
 818           {
 819             prob = probs + SpecPos + ((2 | (posSlot & 1)) << numDirectBits);
 820           }
 821           else
 822           {
 823             numDirectBits -= kNumAlignBits;
 824             do
 825             {
 826               NORMALIZE_CHECK
 827               range >>= 1;
 828               code -= range & (((code - range) >> 31) - 1);
 829               /* if (code >= range) code -= range; */
 830             }
 831             while (--numDirectBits);
 832             prob = probs + Align;
 833             numDirectBits = kNumAlignBits;
 834           }
 835           {
 836             unsigned i = 1;
 837             unsigned m = 1;
 838             do
 839             {
 840               REV_BIT_CHECK(prob, i, m);
 841             }
 842             while (--numDirectBits);
 843           }
 844         }
 845       }
 846     }
 847   }
 848   NORMALIZE_CHECK;
 849   return res;
 850 }
 851
 852
 853 void LzmaDec_InitDicAndState(CLzmaDec *p, Bool initDic, Bool initState)
 854 {
 855   p->remainLen = kMatchSpecLenStart + 1;
 856   p->tempBufSize = 0;
 857
 858   if (initDic)
 859   {
 860     p->processedPos = 0;
 861     p->checkDicSize = 0;
 862     p->remainLen = kMatchSpecLenStart + 2;
 863   }
 864   if (initState)
 865     p->remainLen = kMatchSpecLenStart + 2;
 866 }
 867
 868 void LzmaDec_Init(CLzmaDec *p)
 869 {
 870   p->dicPos = 0;
 871   LzmaDec_InitDicAndState(p, True, True);
 872 }
 873
 874
 875 SRes LzmaDec_DecodeToDic(CLzmaDec *p, SizeT dicLimit, const Byte *src, SizeT *srcLen,
 876     ELzmaFinishMode finishMode, ELzmaStatus *status)
 877 {
 878   SizeT inSize = *srcLen;
 879   (*srcLen) = 0;
 880
 881   *status = LZMA_STATUS_NOT_SPECIFIED;
 882
 883   if (p->remainLen > kMatchSpecLenStart)
 884   {
 885     for (; inSize > 0 && p->tempBufSize < RC_INIT_SIZE; (*srcLen)++, inSize--)
 886       p->tempBuf[p->tempBufSize++] = *src++;
 887     if (p->tempBufSize != 0 && p->tempBuf[0] != 0)
 888       return SZ_ERROR_DATA;
 889     if (p->tempBufSize < RC_INIT_SIZE)
 890     {
 891       *status = LZMA_STATUS_NEEDS_MORE_INPUT;
 892       return SZ_OK;
 893     }
 894     p->code =
 895         ((UInt32)p->tempBuf[1] << 24)
 896       | ((UInt32)p->tempBuf[2] << 16)
 897       | ((UInt32)p->tempBuf[3] << 8)
 898       | ((UInt32)p->tempBuf[4]);
 899     p->range = 0xFFFFFFFF;
 900     p->tempBufSize = 0;
 901
 902     if (p->remainLen > kMatchSpecLenStart + 1)
 903     {
 904       SizeT numProbs = LzmaProps_GetNumProbs(&p->prop);
 905       SizeT i;
 906       CLzmaProb *probs = p->probs;
 907       for (i = 0; i < numProbs; i++)
 908         probs[i] = kBitModelTotal >> 1;
 909       p->reps[0] = p->reps[1] = p->reps[2] = p->reps[3] = 1;
 910       p->state = 0;
 911     }
 912
 913     p->remainLen = 0;
 914   }
 915
 916   LzmaDec_WriteRem(p, dicLimit);
 917
 918   while (p->remainLen != kMatchSpecLenStart)
 919   {
 920       int checkEndMarkNow = 0;
 921
 922       if (p->dicPos >= dicLimit)
 923       {
 924         if (p->remainLen == 0 && p->code == 0)
 925         {
 926           *status = LZMA_STATUS_MAYBE_FINISHED_WITHOUT_MARK;
 927           return SZ_OK;
 928         }
 929         if (finishMode == LZMA_FINISH_ANY)
 930         {
 931           *status = LZMA_STATUS_NOT_FINISHED;
 932           return SZ_OK;
 933         }
 934         if (p->remainLen != 0)
 935         {
 936           *status = LZMA_STATUS_NOT_FINISHED;
 937           return SZ_ERROR_DATA;
 938         }
 939         checkEndMarkNow = 1;
 940       }
 941
 942       if (p->tempBufSize == 0)
 943       {
 944         SizeT processed;
 945         const Byte *bufLimit;
 946         if (inSize < LZMA_REQUIRED_INPUT_MAX || checkEndMarkNow)
 947         {
 948           int dummyRes = LzmaDec_TryDummy(p, src, inSize);
 949           if (dummyRes == DUMMY_ERROR)
 950           {
 951             memcpy(p->tempBuf, src, inSize);
 952             p->tempBufSize = (unsigned)inSize;
 953             (*srcLen) += inSize;
 954             *status = LZMA_STATUS_NEEDS_MORE_INPUT;
 955             return SZ_OK;
 956           }
 957           if (checkEndMarkNow && dummyRes != DUMMY_MATCH)
 958           {
 959             *status = LZMA_STATUS_NOT_FINISHED;
 960             return SZ_ERROR_DATA;
 961           }
 962           bufLimit = src;
 963         }
 964         else
 965           bufLimit = src + inSize - LZMA_REQUIRED_INPUT_MAX;
 966         p->buf = src;
 967         if (LzmaDec_DecodeReal2(p, dicLimit, bufLimit) != 0)
 968           return SZ_ERROR_DATA;
 969         processed = (SizeT)(p->buf - src);
 970         (*srcLen) += processed;
 971         src += processed;
 972         inSize -= processed;
 973       }
 974       else
 975       {
 976         unsigned rem = p->tempBufSize, lookAhead = 0;
 977         while (rem < LZMA_REQUIRED_INPUT_MAX && lookAhead < inSize)
 978           p->tempBuf[rem++] = src[lookAhead++];
 979         p->tempBufSize = rem;
 980         if (rem < LZMA_REQUIRED_INPUT_MAX || checkEndMarkNow)
 981         {
 982           int dummyRes = LzmaDec_TryDummy(p, p->tempBuf, rem);
 983           if (dummyRes == DUMMY_ERROR)
 984           {
 985             (*srcLen) += lookAhead;
 986             *status = LZMA_STATUS_NEEDS_MORE_INPUT;
 987             return SZ_OK;
 988           }
 989           if (checkEndMarkNow && dummyRes != DUMMY_MATCH)
 990           {
 991             *status = LZMA_STATUS_NOT_FINISHED;
 992             return SZ_ERROR_DATA;
 993           }
 994         }
 995         p->buf = p->tempBuf;
 996         if (LzmaDec_DecodeReal2(p, dicLimit, p->buf) != 0)
 997           return SZ_ERROR_DATA;
 998
 999         {
1000           unsigned kkk = (unsigned)(p->buf - p->tempBuf);
1001           if (rem < kkk)
1002             return SZ_ERROR_FAIL; /* some internal error */
1003           rem -= kkk;
1004           if (lookAhead < rem)
1005             return SZ_ERROR_FAIL; /* some internal error */
1006           lookAhead -= rem;
1007         }
1008         (*srcLen) += lookAhead;
1009         src += lookAhead;
1010         inSize -= lookAhead;
1011         p->tempBufSize = 0;
1012       }
1013   }
1014
1015   if (p->code != 0)
1016     return SZ_ERROR_DATA;
1017   *status = LZMA_STATUS_FINISHED_WITH_MARK;
1018   return SZ_OK;
1019 }
1020
1021
1022 SRes LzmaDec_DecodeToBuf(CLzmaDec *p, Byte *dest, SizeT *destLen, const Byte *src, SizeT *srcLen, ELzmaFinishMode finishMode, ELzmaStatus *status)
1023 {
1024   SizeT outSize = *destLen;
1025   SizeT inSize = *srcLen;
1026   *srcLen = *destLen = 0;
1027   for (;;)
1028   {
1029     SizeT inSizeCur = inSize, outSizeCur, dicPos;
1030     ELzmaFinishMode curFinishMode;
1031     SRes res;
1032     if (p->dicPos == p->dicBufSize)
1033       p->dicPos = 0;
1034     dicPos = p->dicPos;
1035     if (outSize > p->dicBufSize - dicPos)
1036     {
1037       outSizeCur = p->dicBufSize;
1038       curFinishMode = LZMA_FINISH_ANY;
1039     }
1040     else
1041     {
1042       outSizeCur = dicPos + outSize;
1043       curFinishMode = finishMode;
1044     }
1045
1046     res = LzmaDec_DecodeToDic(p, outSizeCur, src, &inSizeCur, curFinishMode, status);
1047     src += inSizeCur;
1048     inSize -= inSizeCur;
1049     *srcLen += inSizeCur;
1050     outSizeCur = p->dicPos - dicPos;
1051     memcpy(dest, p->dic + dicPos, outSizeCur);
1052     dest += outSizeCur;
1053     outSize -= outSizeCur;
1054     *destLen += outSizeCur;
1055     if (res != 0)
1056       return res;
1057     if (outSizeCur == 0 || outSize == 0)
1058       return SZ_OK;
1059   }
1060 }
1061
1062 void LzmaDec_FreeProbs(CLzmaDec *p, ISzAllocPtr alloc)
1063 {
1064   ISzAlloc_Free(alloc, p->probs);
1065   p->probs = NULL;
1066 }
1067
1068 static void LzmaDec_FreeDict(CLzmaDec *p, ISzAllocPtr alloc)
1069 {
1070   ISzAlloc_Free(alloc, p->dic);
1071   p->dic = NULL;
1072 }
1073
1074 void LzmaDec_Free(CLzmaDec *p, ISzAllocPtr alloc)
1075 {
1076   LzmaDec_FreeProbs(p, alloc);
1077   LzmaDec_FreeDict(p, alloc);
1078 }
1079
1080 SRes LzmaProps_Decode(CLzmaProps *p, const Byte *data, unsigned size)
1081 {
1082   UInt32 dicSize;
1083   Byte d;
1084
1085   if (size < LZMA_PROPS_SIZE)
1086     return SZ_ERROR_UNSUPPORTED;
1087   else
1088     dicSize = data[1] | ((UInt32)data[2] << 8) | ((UInt32)data[3] << 16) | ((UInt32)data[4] << 24);
1089
1090   if (dicSize < LZMA_DIC_MIN)
1091     dicSize = LZMA_DIC_MIN;
1092   p->dicSize = dicSize;
1093
1094   d = data[0];
1095   if (d >= (9 * 5 * 5))
1096     return SZ_ERROR_UNSUPPORTED;
1097
1098   p->lc = (Byte)(d % 9);
1099   d /= 9;
1100   p->pb = (Byte)(d / 5);
1101   p->lp = (Byte)(d % 5);
1102
1103   return SZ_OK;
1104 }
1105
1106 static SRes LzmaDec_AllocateProbs2(CLzmaDec *p, const CLzmaProps *propNew, ISzAllocPtr alloc)
1107 {
1108   UInt32 numProbs = LzmaProps_GetNumProbs(propNew);
1109   if (!p->probs || numProbs != p->numProbs)
1110   {
1111     LzmaDec_FreeProbs(p, alloc);
1112     p->probs = (CLzmaProb *)ISzAlloc_Alloc(alloc, numProbs * sizeof(CLzmaProb));
1113     if (!p->probs)
1114       return SZ_ERROR_MEM;
1115     p->probs_1664 = p->probs + 1664;
1116     p->numProbs = numProbs;
1117   }
1118   return SZ_OK;
1119 }
1120
1121 SRes LzmaDec_AllocateProbs(CLzmaDec *p, const Byte *props, unsigned propsSize, ISzAllocPtr alloc)
1122 {
1123   CLzmaProps propNew;
1124   RINOK(LzmaProps_Decode(&propNew, props, propsSize));
1125   RINOK(LzmaDec_AllocateProbs2(p, &propNew, alloc));
1126   p->prop = propNew;
1127   return SZ_OK;
1128 }
1129
1130 SRes LzmaDec_Allocate(CLzmaDec *p, const Byte *props, unsigned propsSize, ISzAllocPtr alloc)
1131 {
1132   CLzmaProps propNew;
1133   SizeT dicBufSize;
1134   RINOK(LzmaProps_Decode(&propNew, props, propsSize));
1135   RINOK(LzmaDec_AllocateProbs2(p, &propNew, alloc));
1136
1137   {
1138     UInt32 dictSize = propNew.dicSize;
1139     SizeT mask = ((UInt32)1 << 12) - 1;
1140          if (dictSize >= ((UInt32)1 << 30)) mask = ((UInt32)1 << 22) - 1;
1141     else if (dictSize >= ((UInt32)1 << 22)) mask = ((UInt32)1 << 20) - 1;;
1142     dicBufSize = ((SizeT)dictSize + mask) & ~mask;
1143     if (dicBufSize < dictSize)
1144       dicBufSize = dictSize;
1145   }
1146
1147   if (!p->dic || dicBufSize != p->dicBufSize)
1148   {
1149     LzmaDec_FreeDict(p, alloc);
1150     p->dic = (Byte *)ISzAlloc_Alloc(alloc, dicBufSize);
1151     if (!p->dic)
1152     {
1153       LzmaDec_FreeProbs(p, alloc);
1154       return SZ_ERROR_MEM;
1155     }
1156   }
1157   p->dicBufSize = dicBufSize;
1158   p->prop = propNew;
1159   return SZ_OK;
1160 }
1161
1162 SRes LzmaDecode(Byte *dest, SizeT *destLen, const Byte *src, SizeT *srcLen,
1163     const Byte *propData, unsigned propSize, ELzmaFinishMode finishMode,
1164     ELzmaStatus *status, ISzAllocPtr alloc)
1165 {
1166   CLzmaDec p;
1167   SRes res;
1168   SizeT outSize = *destLen, inSize = *srcLen;
1169   *destLen = *srcLen = 0;
1170   *status = LZMA_STATUS_NOT_SPECIFIED;
1171   if (inSize < RC_INIT_SIZE)
1172     return SZ_ERROR_INPUT_EOF;
1173   LzmaDec_Construct(&p);
1174   RINOK(LzmaDec_AllocateProbs(&p, propData, propSize, alloc));
1175   p.dic = dest;
1176   p.dicBufSize = outSize;
1177   LzmaDec_Init(&p);
1178   *srcLen = inSize;
1179   res = LzmaDec_DecodeToDic(&p, outSize, src, srcLen, finishMode, status);
1180   *destLen = p.dicPos;
1181   if (res == SZ_OK && *status == LZMA_STATUS_NEEDS_MORE_INPUT)
1182     res = SZ_ERROR_INPUT_EOF;
1183   LzmaDec_FreeProbs(&p, alloc);
1184   return res;
1185 }