git.maemo.org Git - physicsfs/blob - lzma/CPP/7zip/Compress/LZMA/LZMADecoder.cpp

   1 // LZMADecoder.cpp
   2
   3 #include "StdAfx.h"
   4
   5 #include "LZMADecoder.h"
   6 #include "../../../Common/Defs.h"
   7
   8 namespace NCompress {
   9 namespace NLZMA {
  10
  11 const int kLenIdFinished = -1;
  12 const int kLenIdNeedInit = -2;
  13
  14 void CDecoder::Init()
  15 {
  16   {
  17     for(int i = 0; i < kNumStates; i++)
  18     {
  19       for (UInt32 j = 0; j <= _posStateMask; j++)
  20       {
  21         _isMatch[i][j].Init();
  22         _isRep0Long[i][j].Init();
  23       }
  24       _isRep[i].Init();
  25       _isRepG0[i].Init();
  26       _isRepG1[i].Init();
  27       _isRepG2[i].Init();
  28     }
  29   }
  30   {
  31     for (UInt32 i = 0; i < kNumLenToPosStates; i++)
  32     _posSlotDecoder[i].Init();
  33   }
  34   {
  35     for(UInt32 i = 0; i < kNumFullDistances - kEndPosModelIndex; i++)
  36       _posDecoders[i].Init();
  37   }
  38   _posAlignDecoder.Init();
  39   _lenDecoder.Init(_posStateMask + 1);
  40   _repMatchLenDecoder.Init(_posStateMask + 1);
  41   _literalDecoder.Init();
  42
  43   _state.Init();
  44   _reps[0] = _reps[1] = _reps[2] = _reps[3] = 0;
  45 }
  46
  47 HRESULT CDecoder::CodeSpec(UInt32 curSize)
  48 {
  49   if (_outSizeDefined)
  50   {
  51     const UInt64 rem = _outSize - _outWindowStream.GetProcessedSize();
  52     if (curSize > rem)
  53       curSize = (UInt32)rem;
  54   }
  55
  56   if (_remainLen == kLenIdFinished)
  57     return S_OK;
  58   if (_remainLen == kLenIdNeedInit)
  59   {
  60     _rangeDecoder.Init();
  61     Init();
  62     _remainLen = 0;
  63   }
  64   if (curSize == 0)
  65     return S_OK;
  66
  67   UInt32 rep0 = _reps[0];
  68   UInt32 rep1 = _reps[1];
  69   UInt32 rep2 = _reps[2];
  70   UInt32 rep3 = _reps[3];
  71   CState state = _state;
  72   Byte previousByte;
  73
  74   while(_remainLen > 0 && curSize > 0)
  75   {
  76     previousByte = _outWindowStream.GetByte(rep0);
  77     _outWindowStream.PutByte(previousByte);
  78     _remainLen--;
  79     curSize--;
  80   }
  81   UInt64 nowPos64 = _outWindowStream.GetProcessedSize();
  82   if (nowPos64 == 0)
  83     previousByte = 0;
  84   else
  85     previousByte = _outWindowStream.GetByte(0);
  86
  87   while(curSize > 0)
  88   {
  89     {
  90       #ifdef _NO_EXCEPTIONS
  91       if (_rangeDecoder.Stream.ErrorCode != S_OK)
  92         return _rangeDecoder.Stream.ErrorCode;
  93       #endif
  94       if (_rangeDecoder.Stream.WasFinished())
  95         return S_FALSE;
  96       UInt32 posState = UInt32(nowPos64) & _posStateMask;
  97       if (_isMatch[state.Index][posState].Decode(&_rangeDecoder) == 0)
  98       {
  99         if(!state.IsCharState())
 100           previousByte = _literalDecoder.DecodeWithMatchByte(&_rangeDecoder,
 101               (UInt32)nowPos64, previousByte, _outWindowStream.GetByte(rep0));
 102         else
 103           previousByte = _literalDecoder.DecodeNormal(&_rangeDecoder,
 104               (UInt32)nowPos64, previousByte);
 105         _outWindowStream.PutByte(previousByte);
 106         state.UpdateChar();
 107         curSize--;
 108         nowPos64++;
 109       }
 110       else
 111       {
 112         UInt32 len;
 113         if(_isRep[state.Index].Decode(&_rangeDecoder) == 1)
 114         {
 115           len = 0;
 116           if(_isRepG0[state.Index].Decode(&_rangeDecoder) == 0)
 117           {
 118             if(_isRep0Long[state.Index][posState].Decode(&_rangeDecoder) == 0)
 119             {
 120               state.UpdateShortRep();
 121               len = 1;
 122             }
 123           }
 124           else
 125           {
 126             UInt32 distance;
 127             if(_isRepG1[state.Index].Decode(&_rangeDecoder) == 0)
 128               distance = rep1;
 129             else
 130             {
 131               if (_isRepG2[state.Index].Decode(&_rangeDecoder) == 0)
 132                 distance = rep2;
 133               else
 134               {
 135                 distance = rep3;
 136                 rep3 = rep2;
 137               }
 138               rep2 = rep1;
 139             }
 140             rep1 = rep0;
 141             rep0 = distance;
 142           }
 143           if (len == 0)
 144           {
 145             len = _repMatchLenDecoder.Decode(&_rangeDecoder, posState) + kMatchMinLen;
 146             state.UpdateRep();
 147           }
 148         }
 149         else
 150         {
 151           rep3 = rep2;
 152           rep2 = rep1;
 153           rep1 = rep0;
 154           len = kMatchMinLen + _lenDecoder.Decode(&_rangeDecoder, posState);
 155           state.UpdateMatch();
 156           UInt32 posSlot = _posSlotDecoder[GetLenToPosState(len)].Decode(&_rangeDecoder);
 157           if (posSlot >= kStartPosModelIndex)
 158           {
 159             UInt32 numDirectBits = (posSlot >> 1) - 1;
 160             rep0 = ((2 | (posSlot & 1)) << numDirectBits);
 161
 162             if (posSlot < kEndPosModelIndex)
 163               rep0 += NRangeCoder::ReverseBitTreeDecode(_posDecoders +
 164                   rep0 - posSlot - 1, &_rangeDecoder, numDirectBits);
 165             else
 166             {
 167               rep0 += (_rangeDecoder.DecodeDirectBits(
 168                   numDirectBits - kNumAlignBits) << kNumAlignBits);
 169               rep0 += _posAlignDecoder.ReverseDecode(&_rangeDecoder);
 170               if (rep0 == 0xFFFFFFFF)
 171               {
 172                 _remainLen = kLenIdFinished;
 173                 return S_OK;
 174               }
 175             }
 176           }
 177           else
 178             rep0 = posSlot;
 179         }
 180         UInt32 locLen = len;
 181         if (len > curSize)
 182           locLen = (UInt32)curSize;
 183         if (!_outWindowStream.CopyBlock(rep0, locLen))
 184           return S_FALSE;
 185         previousByte = _outWindowStream.GetByte(0);
 186         curSize -= locLen;
 187         nowPos64 += locLen;
 188         len -= locLen;
 189         if (len != 0)
 190         {
 191           _remainLen = (Int32)len;
 192           break;
 193         }
 194
 195         #ifdef _NO_EXCEPTIONS
 196         if (_outWindowStream.ErrorCode != S_OK)
 197           return _outWindowStream.ErrorCode;
 198         #endif
 199       }
 200     }
 201   }
 202   if (_rangeDecoder.Stream.WasFinished())
 203     return S_FALSE;
 204   _reps[0] = rep0;
 205   _reps[1] = rep1;
 206   _reps[2] = rep2;
 207   _reps[3] = rep3;
 208   _state = state;
 209
 210   return S_OK;
 211 }
 212
 213 STDMETHODIMP CDecoder::CodeReal(ISequentialInStream *inStream,
 214     ISequentialOutStream *outStream,
 215     const UInt64 *, const UInt64 *outSize,
 216     ICompressProgressInfo *progress)
 217 {
 218   SetInStream(inStream);
 219   _outWindowStream.SetStream(outStream);
 220   SetOutStreamSize(outSize);
 221   CDecoderFlusher flusher(this);
 222
 223   for (;;)
 224   {
 225     UInt32 curSize = 1 << 18;
 226     RINOK(CodeSpec(curSize));
 227     if (_remainLen == kLenIdFinished)
 228       break;
 229     if (progress != NULL)
 230     {
 231       UInt64 inSize = _rangeDecoder.GetProcessedSize();
 232       UInt64 nowPos64 = _outWindowStream.GetProcessedSize();
 233       RINOK(progress->SetRatioInfo(&inSize, &nowPos64));
 234     }
 235     if (_outSizeDefined)
 236       if (_outWindowStream.GetProcessedSize() >= _outSize)
 237         break;
 238   }
 239   flusher.NeedFlush = false;
 240   return Flush();
 241 }
 242
 243
 244 #ifdef _NO_EXCEPTIONS
 245
 246 #define LZMA_TRY_BEGIN
 247 #define LZMA_TRY_END
 248
 249 #else
 250
 251 #define LZMA_TRY_BEGIN try {
 252 #define LZMA_TRY_END } \
 253   catch(const CInBufferException &e)  { return e.ErrorCode; } \
 254   catch(const CLZOutWindowException &e)  { return e.ErrorCode; } \
 255   catch(...) { return S_FALSE; }
 256
 257 #endif
 258
 259
 260 STDMETHODIMP CDecoder::Code(ISequentialInStream *inStream,
 261       ISequentialOutStream *outStream, const UInt64 *inSize, const UInt64 *outSize,
 262       ICompressProgressInfo *progress)
 263 {
 264   LZMA_TRY_BEGIN
 265   return CodeReal(inStream, outStream, inSize, outSize, progress);
 266   LZMA_TRY_END
 267 }
 268
 269 STDMETHODIMP CDecoder::SetDecoderProperties2(const Byte *properties, UInt32 size)
 270 {
 271   if (size < 5)
 272     return E_INVALIDARG;
 273   int lc = properties[0] % 9;
 274   Byte remainder = (Byte)(properties[0] / 9);
 275   int lp = remainder % 5;
 276   int pb = remainder / 5;
 277   if (pb > NLength::kNumPosStatesBitsMax)
 278     return E_INVALIDARG;
 279   _posStateMask = (1 << pb) - 1;
 280   UInt32 dictionarySize = 0;
 281   for (int i = 0; i < 4; i++)
 282     dictionarySize += ((UInt32)(properties[1 + i])) << (i * 8);
 283   if (!_outWindowStream.Create(dictionarySize))
 284     return E_OUTOFMEMORY;
 285   if (!_literalDecoder.Create(lp, lc))
 286     return E_OUTOFMEMORY;
 287   if (!_rangeDecoder.Create(1 << 20))
 288     return E_OUTOFMEMORY;
 289   return S_OK;
 290 }
 291
 292 STDMETHODIMP CDecoder::GetInStreamProcessedSize(UInt64 *value)
 293 {
 294   *value = _rangeDecoder.GetProcessedSize();
 295   return S_OK;
 296 }
 297
 298 STDMETHODIMP CDecoder::SetInStream(ISequentialInStream *inStream)
 299 {
 300   _rangeDecoder.SetStream(inStream);
 301   return S_OK;
 302 }
 303
 304 STDMETHODIMP CDecoder::ReleaseInStream()
 305 {
 306   _rangeDecoder.ReleaseStream();
 307   return S_OK;
 308 }
 309
 310 STDMETHODIMP CDecoder::SetOutStreamSize(const UInt64 *outSize)
 311 {
 312   _outSizeDefined = (outSize != NULL);
 313   if (_outSizeDefined)
 314     _outSize = *outSize;
 315   _remainLen = kLenIdNeedInit;
 316   _outWindowStream.Init();
 317   return S_OK;
 318 }
 319
 320 #ifndef NO_READ_FROM_CODER
 321
 322 STDMETHODIMP CDecoder::Read(void *data, UInt32 size, UInt32 *processedSize)
 323 {
 324   LZMA_TRY_BEGIN
 325   if (processedSize)
 326     *processedSize = 0;
 327   const UInt64 startPos = _outWindowStream.GetProcessedSize();
 328   _outWindowStream.SetMemStream((Byte *)data);
 329   RINOK(CodeSpec(size));
 330   if (processedSize)
 331     *processedSize = (UInt32)(_outWindowStream.GetProcessedSize() - startPos);
 332   return Flush();
 333   LZMA_TRY_END
 334 }
 335
 336 #endif
 337
 338 }}