diff options
Diffstat (limited to '7zip/Compress/Deflate/DeflateDecoder.cpp')
| -rwxr-xr-x | 7zip/Compress/Deflate/DeflateDecoder.cpp | 136 |
1 files changed, 65 insertions, 71 deletions
diff --git a/7zip/Compress/Deflate/DeflateDecoder.cpp b/7zip/Compress/Deflate/DeflateDecoder.cpp index 16369326..629d9981 100755 --- a/7zip/Compress/Deflate/DeflateDecoder.cpp +++ b/7zip/Compress/Deflate/DeflateDecoder.cpp @@ -8,47 +8,58 @@ namespace NCompress { namespace NDeflate { namespace NDecoder { -const int kLenIdFinished = -1; -const int kLenIdNeedInit = -2; +static const int kLenIdFinished = -1; +static const int kLenIdNeedInit = -2; CCoder::CCoder(bool deflate64Mode): _deflate64Mode(deflate64Mode), _keepHistory(false) {} -void CCoder::DeCodeLevelTable(Byte *newLevels, int numLevels) +UInt32 CCoder::ReadBits(int numBits) +{ + return m_InBitStream.ReadBits(numBits); +} + +bool CCoder::DeCodeLevelTable(Byte *values, int numSymbols) { int i = 0; - while (i < numLevels) + do { UInt32 number = m_LevelDecoder.DecodeSymbol(&m_InBitStream); if (number < kTableDirectLevels) - newLevels[i++] = Byte(number); - else + values[i++] = (Byte)number; + else if (number < kLevelTableSize) { if (number == kTableLevelRepNumber) { - int t = m_InBitStream.ReadBits(2) + 3; - for (int reps = t; reps > 0 && i < numLevels ; reps--, i++) - newLevels[i] = newLevels[i - 1]; + if (i == 0) + return false; + int num = ReadBits(2) + 3; + for (; num > 0 && i < numSymbols; num--, i++) + values[i] = values[i - 1]; } else { int num; if (number == kTableLevel0Number) - num = m_InBitStream.ReadBits(3) + 3; + num = ReadBits(3) + 3; else - num = m_InBitStream.ReadBits(7) + 11; - for (;num > 0 && i < numLevels; num--) - newLevels[i++] = 0; + num = ReadBits(7) + 11; + for (;num > 0 && i < numSymbols; num--) + values[i++] = 0; } } + else + return false; } + while(i < numSymbols); + return true; } #define RIF(x) { if (!(x)) return false; } bool CCoder::ReadTables(void) { - m_FinalBlock = (m_InBitStream.ReadBits(kFinalBlockFieldSize) == NFinalBlockField::kFinalBlock); - int blockType = m_InBitStream.ReadBits(kBlockTypeFieldSize); + m_FinalBlock = (ReadBits(kFinalBlockFieldSize) == NFinalBlockField::kFinalBlock); + UInt32 blockType = ReadBits(kBlockTypeFieldSize); if (blockType > NBlockType::kDynamicHuffman) return false; @@ -56,67 +67,52 @@ bool CCoder::ReadTables(void) { m_StoredMode = true; UInt32 currentBitPosition = m_InBitStream.GetBitPosition(); - UInt32 numBitsForAlign = currentBitPosition > 0 ? (8 - currentBitPosition): 0; - if (numBitsForAlign > 0) - m_InBitStream.ReadBits(numBitsForAlign); - m_StoredBlockSize = m_InBitStream.ReadBits(kDeflateStoredBlockLengthFieldSizeSize); - UInt16 onesComplementReverse = ~(UInt16)(m_InBitStream.ReadBits(kDeflateStoredBlockLengthFieldSizeSize)); - return (m_StoredBlockSize == onesComplementReverse); + int numBitsForAlign = (int)(currentBitPosition > 0 ? (8 - currentBitPosition): 0); + ReadBits(numBitsForAlign); + m_StoredBlockSize = ReadBits(kStoredBlockLengthFieldSize); + return (m_StoredBlockSize == (UInt16)~ReadBits(kStoredBlockLengthFieldSize)); } m_StoredMode = false; - Byte litLenLevels[kStaticMainTableSize]; - Byte distLevels[kStaticDistTableSize]; + + CLevels levels; if (blockType == NBlockType::kFixedHuffman) { - int i; - - for (i = 0; i < 144; i++) - litLenLevels[i] = 8; - for (; i < 256; i++) - litLenLevels[i] = 9; - for (; i < 280; i++) - litLenLevels[i] = 7; - for (; i < 288; i++) // make a complete, but wrong code set - litLenLevels[i] = 8; - - for (i = 0; i < kStaticDistTableSize; i++) // test it: InfoZip only uses kDistTableSize - distLevels[i] = 5; + levels.SetFixedLevels(); + _numDistLevels = _deflate64Mode ? kDistTableSize64 : kDistTableSize32; } - else // (blockType == kDynamicHuffman) + else { - int numLitLenLevels = m_InBitStream.ReadBits(kDeflateNumberOfLengthCodesFieldSize) + - kDeflateNumberOfLitLenCodesMin; - int numDistLevels = m_InBitStream.ReadBits(kDeflateNumberOfDistanceCodesFieldSize) + - kDeflateNumberOfDistanceCodesMin; - int numLevelCodes = m_InBitStream.ReadBits(kDeflateNumberOfLevelCodesFieldSize) + - kDeflateNumberOfLevelCodesMin; - - int numLevels = _deflate64Mode ? kHeapTablesSizesSum64 : kHeapTablesSizesSum32; + int numLitLenLevels = ReadBits(kNumLenCodesFieldSize) + kNumLitLenCodesMin; + _numDistLevels = ReadBits(kNumDistCodesFieldSize) + kNumDistCodesMin; + int numLevelCodes = ReadBits(kNumLevelCodesFieldSize) + kNumLevelCodesMin; + + if (!_deflate64Mode) + if (_numDistLevels > kDistTableSize32) + return false; Byte levelLevels[kLevelTableSize]; for (int i = 0; i < kLevelTableSize; i++) { int position = kCodeLengthAlphabetOrder[i]; if(i < numLevelCodes) - levelLevels[position] = Byte(m_InBitStream.ReadBits(kDeflateLevelCodeFieldSize)); + levelLevels[position] = (Byte)ReadBits(kLevelFieldSize); else levelLevels[position] = 0; } RIF(m_LevelDecoder.SetCodeLengths(levelLevels)); - Byte tmpLevels[kStaticMaxTableSize]; - DeCodeLevelTable(tmpLevels, numLitLenLevels + numDistLevels); - - memmove(litLenLevels, tmpLevels, numLitLenLevels); - memset(litLenLevels + numLitLenLevels, 0, kStaticMainTableSize - numLitLenLevels); - - memmove(distLevels, tmpLevels + numLitLenLevels, numDistLevels); - memset(distLevels + numDistLevels, 0, kStaticDistTableSize - numDistLevels); + Byte tmpLevels[kFixedMainTableSize + kFixedDistTableSize]; + if (!DeCodeLevelTable(tmpLevels, numLitLenLevels + _numDistLevels)) + return false; + + levels.SubClear(); + memcpy(levels.litLenLevels, tmpLevels, numLitLenLevels); + memcpy(levels.distLevels, tmpLevels + numLitLenLevels, _numDistLevels); } - RIF(m_MainDecoder.SetCodeLengths(litLenLevels)); - return m_DistDecoder.SetCodeLengths(distLevels); + RIF(m_MainDecoder.SetCodeLengths(levels.litLenLevels)); + return m_DistDecoder.SetCodeLengths(levels.distLevels); } HRESULT CCoder::CodeSpec(UInt32 curSize) @@ -126,10 +122,8 @@ HRESULT CCoder::CodeSpec(UInt32 curSize) if (_remainLen == kLenIdNeedInit) { if (!_keepHistory) - { - if (!m_OutWindowStream.Create(_deflate64Mode ? kHistorySize64: kHistorySize32)) + if (!m_OutWindowStream.Create(_deflate64Mode ? kHistorySize64: kHistorySize32)) return E_OUTOFMEMORY; - } if (!m_InBitStream.Create(1 << 17)) return E_OUTOFMEMORY; m_OutWindowStream.Init(_keepHistory); @@ -177,15 +171,20 @@ HRESULT CCoder::CodeSpec(UInt32 curSize) return S_FALSE; UInt32 number = m_MainDecoder.DecodeSymbol(&m_InBitStream); - if (number < 256) + if (number < 0x100) { m_OutWindowStream.PutByte((Byte)number); curSize--; continue; } - else if (number >= kMatchNumber) + else if (number == kSymbolEndOfBlock) { - number -= kMatchNumber; + _needReadTable = true; + break; + } + else if (number < kMainTableSize) + { + number -= kSymbolMatch; UInt32 len; { int numBits; @@ -205,7 +204,7 @@ HRESULT CCoder::CodeSpec(UInt32 curSize) if (locLen > curSize) locLen = (UInt32)curSize; number = m_DistDecoder.DecodeSymbol(&m_InBitStream); - if (number >= kStaticDistTableSize) + if (number >= _numDistLevels) return S_FALSE; UInt32 distance = kDistStart[number] + m_InBitStream.ReadBits(kDistDirectBits[number]); if (!m_OutWindowStream.CopyBlock(distance, locLen)) @@ -214,16 +213,11 @@ HRESULT CCoder::CodeSpec(UInt32 curSize) len -= locLen; if (len != 0) { - _remainLen = (int)len; + _remainLen = (Int32)len; _rep0 = distance; break; } } - else if (number == kReadTableNumber) - { - _needReadTable = true; - break; - } else return S_FALSE; } @@ -258,8 +252,8 @@ HRESULT CCoder::CodeReal(ISequentialInStream *inStream, break; if (progress != NULL) { - UInt64 inSize = m_InBitStream.GetProcessedSize(); - UInt64 nowPos64 = m_OutWindowStream.GetProcessedSize() - start; + const UInt64 inSize = m_InBitStream.GetProcessedSize(); + const UInt64 nowPos64 = m_OutWindowStream.GetProcessedSize() - start; RINOK(progress->SetRatioInfo(&inSize, &nowPos64)); } } |