target/linux/image/ar7/src/LzmaDecode.c

   1 /*
   2   LzmaDecode.c
   3   LZMA Decoder
   4
   5   LZMA SDK 4.05 Copyright (c) 1999-2004 Igor Pavlov (2004-08-25)
   6   http://www.7-zip.org/
   7
   8   LZMA SDK is licensed under two licenses:
   9   1) GNU Lesser General Public License (GNU LGPL)
  10   2) Common Public License (CPL)
  11   It means that you can select one of these two licenses and
  12   follow rules of that license.
  13
  14   SPECIAL EXCEPTION:
  15   Igor Pavlov, as the author of this code, expressly permits you to
  16   statically or dynamically link your code (or bind by name) to the
  17   interfaces of this file without subjecting your linked code to the
  18   terms of the CPL or GNU LGPL. Any modifications or additions
  19   to this file, however, are subject to the LGPL or CPL terms.
  20 */
  21
  22 #include "LzmaDecode.h"
  23
  24 #ifndef Byte
  25 #define Byte unsigned char
  26 #endif
  27
  28 #define kNumTopBits 24
  29 #define kTopValue ((UInt32)1 << kNumTopBits)
  30
  31 #define kNumBitModelTotalBits 11
  32 #define kBitModelTotal (1 << kNumBitModelTotalBits)
  33 #define kNumMoveBits 5
  34
  35 typedef struct _CRangeDecoder
  36 {
  37   Byte *Buffer;
  38   Byte *BufferLim;
  39   UInt32 Range;
  40   UInt32 Code;
  41   #ifdef _LZMA_IN_CB
  42   ILzmaInCallback *InCallback;
  43   int Result;
  44   #endif
  45   int ExtraBytes;
  46 } CRangeDecoder;
  47
  48 Byte RangeDecoderReadByte(CRangeDecoder *rd)
  49 {
  50   if (rd->Buffer == rd->BufferLim)
  51   {
  52     #ifdef _LZMA_IN_CB
  53     UInt32 size;
  54     rd->Result = rd->InCallback->Read(rd->InCallback, &rd->Buffer, &size);
  55     rd->BufferLim = rd->Buffer + size;
  56     if (size == 0)
  57     #endif
  58     {
  59       rd->ExtraBytes = 1;
  60       return 0xFF;
  61     }
  62   }
  63   return (*rd->Buffer++);
  64 }
  65
  66 /* #define ReadByte (*rd->Buffer++) */
  67 #define ReadByte (RangeDecoderReadByte(rd))
  68
  69 void RangeDecoderInit(CRangeDecoder *rd,
  70   #ifdef _LZMA_IN_CB
  71     ILzmaInCallback *inCallback
  72   #else
  73     Byte *stream, UInt32 bufferSize
  74   #endif
  75     )
  76 {
  77   int i;
  78   #ifdef _LZMA_IN_CB
  79   rd->InCallback = inCallback;
  80   rd->Buffer = rd->BufferLim = 0;
  81   #else
  82   rd->Buffer = stream;
  83   rd->BufferLim = stream + bufferSize;
  84   #endif
  85   rd->ExtraBytes = 0;
  86   rd->Code = 0;
  87   rd->Range = (0xFFFFFFFF);
  88   for(i = 0; i < 5; i++)
  89     rd->Code = (rd->Code << 8) | ReadByte;
  90 }
  91
  92 #define RC_INIT_VAR UInt32 range = rd->Range; UInt32 code = rd->Code;
  93 #define RC_FLUSH_VAR rd->Range = range; rd->Code = code;
  94 #define RC_NORMALIZE if (range < kTopValue) { range <<= 8; code = (code << 8) | ReadByte; }
  95
  96 UInt32 RangeDecoderDecodeDirectBits(CRangeDecoder *rd, int numTotalBits)
  97 {
  98   RC_INIT_VAR
  99   UInt32 result = 0;
 100   int i;
 101   for (i = numTotalBits; i > 0; i--)
 102   {
 103     /* UInt32 t; */
 104     range >>= 1;
 105
 106     result <<= 1;
 107     if (code >= range)
 108     {
 109       code -= range;
 110       result |= 1;
 111     }
 112     /*
 113     t = (code - range) >> 31;
 114     t &= 1;
 115     code -= range & (t - 1);
 116     result = (result + result) | (1 - t);
 117     */
 118     RC_NORMALIZE
 119   }
 120   RC_FLUSH_VAR
 121   return result;
 122 }
 123
 124 int RangeDecoderBitDecode(CProb *prob, CRangeDecoder *rd)
 125 {
 126   UInt32 bound = (rd->Range >> kNumBitModelTotalBits) * *prob;
 127   if (rd->Code < bound)
 128   {
 129     rd->Range = bound;
 130     *prob += (kBitModelTotal - *prob) >> kNumMoveBits;
 131     if (rd->Range < kTopValue)
 132     {
 133       rd->Code = (rd->Code << 8) | ReadByte;
 134       rd->Range <<= 8;
 135     }
 136     return 0;
 137   }
 138   else
 139   {
 140     rd->Range -= bound;
 141     rd->Code -= bound;
 142     *prob -= (*prob) >> kNumMoveBits;
 143     if (rd->Range < kTopValue)
 144     {
 145       rd->Code = (rd->Code << 8) | ReadByte;
 146       rd->Range <<= 8;
 147     }
 148     return 1;
 149   }
 150 }
 151
 152 #define RC_GET_BIT2(prob, mi, A0, A1) \
 153   UInt32 bound = (range >> kNumBitModelTotalBits) * *prob; \
 154   if (code < bound) \
 155     { A0; range = bound; *prob += (kBitModelTotal - *prob) >> kNumMoveBits; mi <<= 1; } \
 156   else \
 157     { A1; range -= bound; code -= bound; *prob -= (*prob) >> kNumMoveBits; mi = (mi + mi) + 1; } \
 158   RC_NORMALIZE
 159
 160 #define RC_GET_BIT(prob, mi) RC_GET_BIT2(prob, mi, ; , ;)
 161
 162 int RangeDecoderBitTreeDecode(CProb *probs, int numLevels, CRangeDecoder *rd)
 163 {
 164   int mi = 1;
 165   int i;
 166   #ifdef _LZMA_LOC_OPT
 167   RC_INIT_VAR
 168   #endif
 169   for(i = numLevels; i > 0; i--)
 170   {
 171     #ifdef _LZMA_LOC_OPT
 172     CProb *prob = probs + mi;
 173     RC_GET_BIT(prob, mi)
 174     #else
 175     mi = (mi + mi) + RangeDecoderBitDecode(probs + mi, rd);
 176     #endif
 177   }
 178   #ifdef _LZMA_LOC_OPT
 179   RC_FLUSH_VAR
 180   #endif
 181   return mi - (1 << numLevels);
 182 }
 183
 184 int RangeDecoderReverseBitTreeDecode(CProb *probs, int numLevels, CRangeDecoder *rd)
 185 {
 186   int mi = 1;
 187   int i;
 188   int symbol = 0;
 189   #ifdef _LZMA_LOC_OPT
 190   RC_INIT_VAR
 191   #endif
 192   for(i = 0; i < numLevels; i++)
 193   {
 194     #ifdef _LZMA_LOC_OPT
 195     CProb *prob = probs + mi;
 196     RC_GET_BIT2(prob, mi, ; , symbol |= (1 << i))
 197     #else
 198     int bit = RangeDecoderBitDecode(probs + mi, rd);
 199     mi = mi + mi + bit;
 200     symbol |= (bit << i);
 201     #endif
 202   }
 203   #ifdef _LZMA_LOC_OPT
 204   RC_FLUSH_VAR
 205   #endif
 206   return symbol;
 207 }
 208
 209 Byte LzmaLiteralDecode(CProb *probs, CRangeDecoder *rd)
 210 {
 211   int symbol = 1;
 212   #ifdef _LZMA_LOC_OPT
 213   RC_INIT_VAR
 214   #endif
 215   do
 216   {
 217     #ifdef _LZMA_LOC_OPT
 218     CProb *prob = probs + symbol;
 219     RC_GET_BIT(prob, symbol)
 220     #else
 221     symbol = (symbol + symbol) | RangeDecoderBitDecode(probs + symbol, rd);
 222     #endif
 223   }
 224   while (symbol < 0x100);
 225   #ifdef _LZMA_LOC_OPT
 226   RC_FLUSH_VAR
 227   #endif
 228   return symbol;
 229 }
 230
 231 Byte LzmaLiteralDecodeMatch(CProb *probs, CRangeDecoder *rd, Byte matchByte)
 232 {
 233   int symbol = 1;
 234   #ifdef _LZMA_LOC_OPT
 235   RC_INIT_VAR
 236   #endif
 237   do
 238   {
 239     int bit;
 240     int matchBit = (matchByte >> 7) & 1;
 241     matchByte <<= 1;
 242     #ifdef _LZMA_LOC_OPT
 243     {
 244       CProb *prob = probs + ((1 + matchBit) << 8) + symbol;
 245       RC_GET_BIT2(prob, symbol, bit = 0, bit = 1)
 246     }
 247     #else
 248     bit = RangeDecoderBitDecode(probs + ((1 + matchBit) << 8) + symbol, rd);
 249     symbol = (symbol << 1) | bit;
 250     #endif
 251     if (matchBit != bit)
 252     {
 253       while (symbol < 0x100)
 254       {
 255         #ifdef _LZMA_LOC_OPT
 256         CProb *prob = probs + symbol;
 257         RC_GET_BIT(prob, symbol)
 258         #else
 259         symbol = (symbol + symbol) | RangeDecoderBitDecode(probs + symbol, rd);
 260         #endif
 261       }
 262       break;
 263     }
 264   }
 265   while (symbol < 0x100);
 266   #ifdef _LZMA_LOC_OPT
 267   RC_FLUSH_VAR
 268   #endif
 269   return symbol;
 270 }
 271
 272 #define kNumPosBitsMax 4
 273 #define kNumPosStatesMax (1 << kNumPosBitsMax)
 274
 275 #define kLenNumLowBits 3
 276 #define kLenNumLowSymbols (1 << kLenNumLowBits)
 277 #define kLenNumMidBits 3
 278 #define kLenNumMidSymbols (1 << kLenNumMidBits)
 279 #define kLenNumHighBits 8
 280 #define kLenNumHighSymbols (1 << kLenNumHighBits)
 281
 282 #define LenChoice 0
 283 #define LenChoice2 (LenChoice + 1)
 284 #define LenLow (LenChoice2 + 1)
 285 #define LenMid (LenLow + (kNumPosStatesMax << kLenNumLowBits))
 286 #define LenHigh (LenMid + (kNumPosStatesMax << kLenNumMidBits))
 287 #define kNumLenProbs (LenHigh + kLenNumHighSymbols)
 288
 289 int LzmaLenDecode(CProb *p, CRangeDecoder *rd, int posState)
 290 {
 291   if(RangeDecoderBitDecode(p + LenChoice, rd) == 0)
 292     return RangeDecoderBitTreeDecode(p + LenLow +
 293         (posState << kLenNumLowBits), kLenNumLowBits, rd);
 294   if(RangeDecoderBitDecode(p + LenChoice2, rd) == 0)
 295     return kLenNumLowSymbols + RangeDecoderBitTreeDecode(p + LenMid +
 296         (posState << kLenNumMidBits), kLenNumMidBits, rd);
 297   return kLenNumLowSymbols + kLenNumMidSymbols +
 298       RangeDecoderBitTreeDecode(p + LenHigh, kLenNumHighBits, rd);
 299 }
 300
 301 #define kNumStates 12
 302
 303 #define kStartPosModelIndex 4
 304 #define kEndPosModelIndex 14
 305 #define kNumFullDistances (1 << (kEndPosModelIndex >> 1))
 306
 307 #define kNumPosSlotBits 6
 308 #define kNumLenToPosStates 4
 309
 310 #define kNumAlignBits 4
 311 #define kAlignTableSize (1 << kNumAlignBits)
 312
 313 #define kMatchMinLen 2
 314
 315 #define IsMatch 0
 316 #define IsRep (IsMatch + (kNumStates << kNumPosBitsMax))
 317 #define IsRepG0 (IsRep + kNumStates)
 318 #define IsRepG1 (IsRepG0 + kNumStates)
 319 #define IsRepG2 (IsRepG1 + kNumStates)
 320 #define IsRep0Long (IsRepG2 + kNumStates)
 321 #define PosSlot (IsRep0Long + (kNumStates << kNumPosBitsMax))
 322 #define SpecPos (PosSlot + (kNumLenToPosStates << kNumPosSlotBits))
 323 #define Align (SpecPos + kNumFullDistances - kEndPosModelIndex)
 324 #define LenCoder (Align + kAlignTableSize)
 325 #define RepLenCoder (LenCoder + kNumLenProbs)
 326 #define Literal (RepLenCoder + kNumLenProbs)
 327
 328 #if Literal != LZMA_BASE_SIZE
 329 StopCompilingDueBUG
 330 #endif
 331
 332 #ifdef _LZMA_OUT_READ
 333
 334 typedef struct _LzmaVarState
 335 {
 336   CRangeDecoder RangeDecoder;
 337   Byte *Dictionary;
 338   UInt32 DictionarySize;
 339   UInt32 DictionaryPos;
 340   UInt32 GlobalPos;
 341   UInt32 Reps[4];
 342   int lc;
 343   int lp;
 344   int pb;
 345   int State;
 346   int PreviousIsMatch;
 347   int RemainLen;
 348 } LzmaVarState;
 349
 350 int LzmaDecoderInit(
 351     unsigned char *buffer, UInt32 bufferSize,
 352     int lc, int lp, int pb,
 353     unsigned char *dictionary, UInt32 dictionarySize,
 354     #ifdef _LZMA_IN_CB
 355     ILzmaInCallback *inCallback
 356     #else
 357     unsigned char *inStream, UInt32 inSize
 358     #endif
 359     )
 360 {
 361   LzmaVarState *vs = (LzmaVarState *)buffer;
 362   CProb *p = (CProb *)(buffer + sizeof(LzmaVarState));
 363   UInt32 numProbs = Literal + ((UInt32)LZMA_LIT_SIZE << (lc + lp));
 364   UInt32 i;
 365   if (bufferSize < numProbs * sizeof(CProb) + sizeof(LzmaVarState))
 366     return LZMA_RESULT_NOT_ENOUGH_MEM;
 367   vs->Dictionary = dictionary;
 368   vs->DictionarySize = dictionarySize;
 369   vs->DictionaryPos = 0;
 370   vs->GlobalPos = 0;
 371   vs->Reps[0] = vs->Reps[1] = vs->Reps[2] = vs->Reps[3] = 1;
 372   vs->lc = lc;
 373   vs->lp = lp;
 374   vs->pb = pb;
 375   vs->State = 0;
 376   vs->PreviousIsMatch = 0;
 377   vs->RemainLen = 0;
 378   dictionary[dictionarySize - 1] = 0;
 379   for (i = 0; i < numProbs; i++)
 380     p[i] = kBitModelTotal >> 1;
 381   RangeDecoderInit(&vs->RangeDecoder,
 382       #ifdef _LZMA_IN_CB
 383       inCallback
 384       #else
 385       inStream, inSize
 386       #endif
 387   );
 388   return LZMA_RESULT_OK;
 389 }
 390
 391 int LzmaDecode(unsigned char *buffer,
 392     unsigned char *outStream, UInt32 outSize,
 393     UInt32 *outSizeProcessed)
 394 {
 395   LzmaVarState *vs = (LzmaVarState *)buffer;
 396   CProb *p = (CProb *)(buffer + sizeof(LzmaVarState));
 397   CRangeDecoder rd = vs->RangeDecoder;
 398   int state = vs->State;
 399   int previousIsMatch = vs->PreviousIsMatch;
 400   Byte previousByte;
 401   UInt32 rep0 = vs->Reps[0], rep1 = vs->Reps[1], rep2 = vs->Reps[2], rep3 = vs->Reps[3];
 402   UInt32 nowPos = 0;
 403   UInt32 posStateMask = (1 << (vs->pb)) - 1;
 404   UInt32 literalPosMask = (1 << (vs->lp)) - 1;
 405   int lc = vs->lc;
 406   int len = vs->RemainLen;
 407   UInt32 globalPos = vs->GlobalPos;
 408
 409   Byte *dictionary = vs->Dictionary;
 410   UInt32 dictionarySize = vs->DictionarySize;
 411   UInt32 dictionaryPos = vs->DictionaryPos;
 412
 413   if (len == -1)
 414   {
 415     *outSizeProcessed = 0;
 416     return LZMA_RESULT_OK;
 417   }
 418
 419   while(len > 0 && nowPos < outSize)
 420   {
 421     UInt32 pos = dictionaryPos - rep0;
 422     if (pos >= dictionarySize)
 423       pos += dictionarySize;
 424     outStream[nowPos++] = dictionary[dictionaryPos] = dictionary[pos];
 425     if (++dictionaryPos == dictionarySize)
 426       dictionaryPos = 0;
 427     len--;
 428   }
 429   if (dictionaryPos == 0)
 430     previousByte = dictionary[dictionarySize - 1];
 431   else
 432     previousByte = dictionary[dictionaryPos - 1];
 433 #else
 434
 435 int LzmaDecode(
 436     Byte *buffer, UInt32 bufferSize,
 437     int lc, int lp, int pb,
 438     #ifdef _LZMA_IN_CB
 439     ILzmaInCallback *inCallback,
 440     #else
 441     unsigned char *inStream, UInt32 inSize,
 442     #endif
 443     unsigned char *outStream, UInt32 outSize,
 444     UInt32 *outSizeProcessed)
 445 {
 446   UInt32 numProbs = Literal + ((UInt32)LZMA_LIT_SIZE << (lc + lp));
 447   CProb *p = (CProb *)buffer;
 448   CRangeDecoder rd;
 449   UInt32 i;
 450   int state = 0;
 451   int previousIsMatch = 0;
 452   Byte previousByte = 0;
 453   UInt32 rep0 = 1, rep1 = 1, rep2 = 1, rep3 = 1;
 454   UInt32 nowPos = 0;
 455   UInt32 posStateMask = (1 << pb) - 1;
 456   UInt32 literalPosMask = (1 << lp) - 1;
 457   int len = 0;
 458   if (bufferSize < numProbs * sizeof(CProb))
 459     return LZMA_RESULT_NOT_ENOUGH_MEM;
 460   for (i = 0; i < numProbs; i++)
 461     p[i] = kBitModelTotal >> 1;
 462   RangeDecoderInit(&rd,
 463       #ifdef _LZMA_IN_CB
 464       inCallback
 465       #else
 466       inStream, inSize
 467       #endif
 468       );
 469 #endif
 470
 471   *outSizeProcessed = 0;
 472   while(nowPos < outSize)
 473   {
 474     int posState = (int)(
 475         (nowPos
 476         #ifdef _LZMA_OUT_READ
 477         + globalPos
 478         #endif
 479         )
 480         & posStateMask);
 481     #ifdef _LZMA_IN_CB
 482     if (rd.Result != LZMA_RESULT_OK)
 483       return rd.Result;
 484     #endif
 485     if (rd.ExtraBytes != 0)
 486       return LZMA_RESULT_DATA_ERROR;
 487     if (RangeDecoderBitDecode(p + IsMatch + (state << kNumPosBitsMax) + posState, &rd) == 0)
 488     {
 489       CProb *probs = p + Literal + (LZMA_LIT_SIZE *
 490         (((
 491         (nowPos
 492         #ifdef _LZMA_OUT_READ
 493         + globalPos
 494         #endif
 495         )
 496         & literalPosMask) << lc) + (previousByte >> (8 - lc))));
 497
 498       if (state < 4) state = 0;
 499       else if (state < 10) state -= 3;
 500       else state -= 6;
 501       if (previousIsMatch)
 502       {
 503         Byte matchByte;
 504         #ifdef _LZMA_OUT_READ
 505         UInt32 pos = dictionaryPos - rep0;
 506         if (pos >= dictionarySize)
 507           pos += dictionarySize;
 508         matchByte = dictionary[pos];
 509         #else
 510         matchByte = outStream[nowPos - rep0];
 511         #endif
 512         previousByte = LzmaLiteralDecodeMatch(probs, &rd, matchByte);
 513         previousIsMatch = 0;
 514       }
 515       else
 516         previousByte = LzmaLiteralDecode(probs, &rd);
 517       outStream[nowPos++] = previousByte;
 518       #ifdef _LZMA_OUT_READ
 519       dictionary[dictionaryPos] = previousByte;
 520       if (++dictionaryPos == dictionarySize)
 521         dictionaryPos = 0;
 522       #endif
 523     }
 524     else
 525     {
 526       previousIsMatch = 1;
 527       if (RangeDecoderBitDecode(p + IsRep + state, &rd) == 1)
 528       {
 529         if (RangeDecoderBitDecode(p + IsRepG0 + state, &rd) == 0)
 530         {
 531           if (RangeDecoderBitDecode(p + IsRep0Long + (state << kNumPosBitsMax) + posState, &rd) == 0)
 532           {
 533             #ifdef _LZMA_OUT_READ
 534             UInt32 pos;
 535             #endif
 536             if (
 537                (nowPos
 538                 #ifdef _LZMA_OUT_READ
 539                 + globalPos
 540                 #endif
 541                )
 542                == 0)
 543               return LZMA_RESULT_DATA_ERROR;
 544             state = state < 7 ? 9 : 11;
 545             #ifdef _LZMA_OUT_READ
 546             pos = dictionaryPos - rep0;
 547             if (pos >= dictionarySize)
 548               pos += dictionarySize;
 549             previousByte = dictionary[pos];
 550             dictionary[dictionaryPos] = previousByte;
 551             if (++dictionaryPos == dictionarySize)
 552               dictionaryPos = 0;
 553             #else
 554             previousByte = outStream[nowPos - rep0];
 555             #endif
 556             outStream[nowPos++] = previousByte;
 557             continue;
 558           }
 559         }
 560         else
 561         {
 562           UInt32 distance;
 563           if(RangeDecoderBitDecode(p + IsRepG1 + state, &rd) == 0)
 564             distance = rep1;
 565           else
 566           {
 567             if(RangeDecoderBitDecode(p + IsRepG2 + state, &rd) == 0)
 568               distance = rep2;
 569             else
 570             {
 571               distance = rep3;
 572               rep3 = rep2;
 573             }
 574             rep2 = rep1;
 575           }
 576           rep1 = rep0;
 577           rep0 = distance;
 578         }
 579         len = LzmaLenDecode(p + RepLenCoder, &rd, posState);
 580         state = state < 7 ? 8 : 11;
 581       }
 582       else
 583       {
 584         int posSlot;
 585         rep3 = rep2;
 586         rep2 = rep1;
 587         rep1 = rep0;
 588         state = state < 7 ? 7 : 10;
 589         len = LzmaLenDecode(p + LenCoder, &rd, posState);
 590         posSlot = RangeDecoderBitTreeDecode(p + PosSlot +
 591             ((len < kNumLenToPosStates ? len : kNumLenToPosStates - 1) <<
 592             kNumPosSlotBits), kNumPosSlotBits, &rd);
 593         if (posSlot >= kStartPosModelIndex)
 594         {
 595           int numDirectBits = ((posSlot >> 1) - 1);
 596           rep0 = ((2 | ((UInt32)posSlot & 1)) << numDirectBits);
 597           if (posSlot < kEndPosModelIndex)
 598           {
 599             rep0 += RangeDecoderReverseBitTreeDecode(
 600                 p + SpecPos + rep0 - posSlot - 1, numDirectBits, &rd);
 601           }
 602           else
 603           {
 604             rep0 += RangeDecoderDecodeDirectBits(&rd,
 605                 numDirectBits - kNumAlignBits) << kNumAlignBits;
 606             rep0 += RangeDecoderReverseBitTreeDecode(p + Align, kNumAlignBits, &rd);
 607           }
 608         }
 609         else
 610           rep0 = posSlot;
 611         rep0++;
 612       }
 613       if (rep0 == (UInt32)(0))
 614       {
 615         /* it's for stream version */
 616         len = -1;
 617         break;
 618       }
 619       if (rep0 > nowPos
 620         #ifdef _LZMA_OUT_READ
 621         + globalPos
 622         #endif
 623         )
 624       {
 625         return LZMA_RESULT_DATA_ERROR;
 626       }
 627       len += kMatchMinLen;
 628       do
 629       {
 630         #ifdef _LZMA_OUT_READ
 631         UInt32 pos = dictionaryPos - rep0;
 632         if (pos >= dictionarySize)
 633           pos += dictionarySize;
 634         previousByte = dictionary[pos];
 635         dictionary[dictionaryPos] = previousByte;
 636         if (++dictionaryPos == dictionarySize)
 637           dictionaryPos = 0;
 638         #else
 639         previousByte = outStream[nowPos - rep0];
 640         #endif
 641         outStream[nowPos++] = previousByte;
 642         len--;
 643       }
 644       while(len > 0 && nowPos < outSize);
 645     }
 646   }
 647
 648   #ifdef _LZMA_OUT_READ
 649   vs->RangeDecoder = rd;
 650   vs->DictionaryPos = dictionaryPos;
 651   vs->GlobalPos = globalPos + nowPos;
 652   vs->Reps[0] = rep0;
 653   vs->Reps[1] = rep1;
 654   vs->Reps[2] = rep2;
 655   vs->Reps[3] = rep3;
 656   vs->State = state;
 657   vs->PreviousIsMatch = previousIsMatch;
 658   vs->RemainLen = len;
 659   #endif
 660
 661   *outSizeProcessed = nowPos;
 662   return LZMA_RESULT_OK;
 663 }