// LzxDecoder.cpp
#include "StdAfx.h"
#include "../../Common/Defs.h"
#include "LzxDecoder.h"
namespace NCompress {
namespace NLzx {
const int kLenIdNeedInit = -2;
CDecoder::CDecoder(bool wimMode):
_keepHistory(false),
_skipByte(false),
_wimMode(wimMode)
{
m_x86ConvertOutStreamSpec = new Cx86ConvertOutStream;
m_x86ConvertOutStream = m_x86ConvertOutStreamSpec;
}
void CDecoder::ReleaseStreams()
{
m_OutWindowStream.ReleaseStream();
m_InBitStream.ReleaseStream();
m_x86ConvertOutStreamSpec->ReleaseStream();
}
STDMETHODIMP CDecoder::Flush()
{
RINOK(m_OutWindowStream.Flush());
return m_x86ConvertOutStreamSpec->Flush();
}
UInt32 CDecoder::ReadBits(unsigned numBits) { return m_InBitStream.ReadBits(numBits); }
#define RIF(x) { if (!(x)) return false; }
bool CDecoder::ReadTable(Byte *lastLevels, Byte *newLevels, UInt32 numSymbols)
{
Byte levelLevels[kLevelTableSize];
UInt32 i;
for (i = 0; i < kLevelTableSize; i++)
levelLevels[i] = (Byte)ReadBits(kNumBitsForPreTreeLevel);
RIF(m_LevelDecoder.SetCodeLengths(levelLevels));
unsigned num = 0;
Byte symbol = 0;
for (i = 0; i < numSymbols;)
{
if (num != 0)
{
lastLevels[i] = newLevels[i] = symbol;
i++;
num--;
continue;
}
UInt32 number = m_LevelDecoder.DecodeSymbol(&m_InBitStream);
if (number == kLevelSymbolZeros)
{
num = kLevelSymbolZerosStartValue + (unsigned)ReadBits(kLevelSymbolZerosNumBits);
symbol = 0;
}
else if (number == kLevelSymbolZerosBig)
{
num = kLevelSymbolZerosBigStartValue + (unsigned)ReadBits(kLevelSymbolZerosBigNumBits);
symbol = 0;
}
else if (number == kLevelSymbolSame || number <= kNumHuffmanBits)
{
if (number <= kNumHuffmanBits)
num = 1;
else
{
num = kLevelSymbolSameStartValue + (unsigned)ReadBits(kLevelSymbolSameNumBits);
number = m_LevelDecoder.DecodeSymbol(&m_InBitStream);
if (number > kNumHuffmanBits)
return false;
}
symbol = Byte((17 + lastLevels[i] - number) % (kNumHuffmanBits + 1));
}
else
return false;
}
return true;
}
bool CDecoder::ReadTables(void)
{
Byte newLevels[kMaxTableSize];
{
if (_skipByte)
m_InBitStream.DirectReadByte();
m_InBitStream.Normalize();
unsigned blockType = (unsigned)ReadBits(kNumBlockTypeBits);
if (blockType > kBlockTypeUncompressed)
return false;
if (_wimMode)
if (ReadBits(1) == 1)
m_UnCompressedBlockSize = (1 << 15);
else
m_UnCompressedBlockSize = ReadBits(16);
else
m_UnCompressedBlockSize = m_InBitStream.ReadBitsBig(kUncompressedBlockSizeNumBits);
m_IsUncompressedBlock = (blockType == kBlockTypeUncompressed);
_skipByte = (m_IsUncompressedBlock && ((m_UnCompressedBlockSize & 1) != 0));
if (m_IsUncompressedBlock)
{
ReadBits(16 - m_InBitStream.GetBitPosition());
if (!m_InBitStream.ReadUInt32(m_RepDistances[0]))
return false;
m_RepDistances[0]--;
for (unsigned i = 1; i < kNumRepDistances; i++)
{
UInt32 rep = 0;
for (unsigned j = 0; j < 4; j++)
rep |= (UInt32)m_InBitStream.DirectReadByte() << (8 * j);
m_RepDistances[i] = rep - 1;
}
return true;
}
m_AlignIsUsed = (blockType == kBlockTypeAligned);
if (m_AlignIsUsed)
{
for (unsigned i = 0; i < kAlignTableSize; i++)
newLevels[i] = (Byte)ReadBits(kNumBitsForAlignLevel);
RIF(m_AlignDecoder.SetCodeLengths(newLevels));
}
}
RIF(ReadTable(m_LastMainLevels, newLevels, 256));
RIF(ReadTable(m_LastMainLevels + 256, newLevels + 256, m_NumPosLenSlots));
for (UInt32 i = 256 + m_NumPosLenSlots; i < kMainTableSize; i++)
newLevels[i] = 0;
RIF(m_MainDecoder.SetCodeLengths(newLevels));
RIF(ReadTable(m_LastLenLevels, newLevels, kNumLenSymbols));
return m_LenDecoder.SetCodeLengths(newLevels);
}
class CDecoderFlusher
{
CDecoder *m_Decoder;
public:
bool NeedFlush;
CDecoderFlusher(CDecoder *decoder): m_Decoder(decoder), NeedFlush(true) {}
~CDecoderFlusher()
{
if (NeedFlush)
m_Decoder->Flush();
m_Decoder->ReleaseStreams();
}
};
void CDecoder::ClearPrevLevels()
{
unsigned i;
for (i = 0; i < kMainTableSize; i++)
m_LastMainLevels[i] = 0;
for (i = 0; i < kNumLenSymbols; i++)
m_LastLenLevels[i] = 0;
}
HRESULT CDecoder::CodeSpec(UInt32 curSize)
{
if (_remainLen == kLenIdNeedInit)
{
_remainLen = 0;
m_InBitStream.Init();
if (!_keepHistory || !m_IsUncompressedBlock)
m_InBitStream.Normalize();
if (!_keepHistory)
{
_skipByte = false;
m_UnCompressedBlockSize = 0;
ClearPrevLevels();
UInt32 i86TranslationSize = 12000000;
bool translationMode = true;
if (!_wimMode)
{
translationMode = (ReadBits(1) != 0);
if (translationMode)
{
i86TranslationSize = ReadBits(16) << 16;
i86TranslationSize |= ReadBits(16);
}
}
m_x86ConvertOutStreamSpec->Init(translationMode, i86TranslationSize);
for (unsigned i = 0 ; i < kNumRepDistances; i++)
m_RepDistances[i] = 0;
}
}
while (_remainLen > 0 && curSize > 0)
{
m_OutWindowStream.PutByte(m_OutWindowStream.GetByte(m_RepDistances[0]));
_remainLen--;
curSize--;
}
while (curSize > 0)
{
if (m_UnCompressedBlockSize == 0)
if (!ReadTables())
return S_FALSE;
UInt32 next = (Int32)MyMin(m_UnCompressedBlockSize, curSize);
curSize -= next;
m_UnCompressedBlockSize -= next;
if (m_IsUncompressedBlock)
{
while (next > 0)
{
m_OutWindowStream.PutByte(m_InBitStream.DirectReadByte());
next--;
}
}
else while (next > 0)
{
UInt32 number = m_MainDecoder.DecodeSymbol(&m_InBitStream);
if (number < 256)
{
m_OutWindowStream.PutByte((Byte)number);
next--;
}
else
{
UInt32 posLenSlot = number - 256;
if (posLenSlot >= m_NumPosLenSlots)
return S_FALSE;
UInt32 posSlot = posLenSlot / kNumLenSlots;
UInt32 lenSlot = posLenSlot % kNumLenSlots;
UInt32 len = kMatchMinLen + lenSlot;
if (lenSlot == kNumLenSlots - 1)
{
UInt32 lenTemp = m_LenDecoder.DecodeSymbol(&m_InBitStream);
if (lenTemp >= kNumLenSymbols)
return S_FALSE;
len += lenTemp;
}
if (posSlot < kNumRepDistances)
{
UInt32 distance = m_RepDistances[posSlot];
m_RepDistances[posSlot] = m_RepDistances[0];
m_RepDistances[0] = distance;
}
else
{
UInt32 distance;
unsigned numDirectBits;
if (posSlot < kNumPowerPosSlots)
{
numDirectBits = (unsigned)(posSlot >> 1) - 1;
distance = ((2 | (posSlot & 1)) << numDirectBits);
}
else
{
numDirectBits = kNumLinearPosSlotBits;
distance = ((posSlot - 0x22) << kNumLinearPosSlotBits);
}
if (m_AlignIsUsed && numDirectBits >= kNumAlignBits)
{
distance += (m_InBitStream.ReadBits(numDirectBits - kNumAlignBits) << kNumAlignBits);
UInt32 alignTemp = m_AlignDecoder.DecodeSymbol(&m_InBitStream);
if (alignTemp >= kAlignTableSize)
return S_FALSE;
distance += alignTemp;
}
else
distance += m_InBitStream.ReadBits(numDirectBits);
m_RepDistances[2] = m_RepDistances[1];
m_RepDistances[1] = m_RepDistances[0];
m_RepDistances[0] = distance - kNumRepDistances;
}
UInt32 locLen = len;
if (locLen > next)
locLen = next;
if (!m_OutWindowStream.CopyBlock(m_RepDistances[0], locLen))
return S_FALSE;
len -= locLen;
next -= locLen;
if (len != 0)
{
_remainLen = (int)len;
return S_OK;
}
}
}
}
return S_OK;
}
HRESULT CDecoder::CodeReal(ISequentialInStream *inStream, ISequentialOutStream *outStream,
const UInt64 *, const UInt64 *outSize, ICompressProgressInfo *progress)
{
if (outSize == NULL)
return E_INVALIDARG;
UInt64 size = *outSize;
RINOK(SetInStream(inStream));
m_x86ConvertOutStreamSpec->SetStream(outStream);
m_OutWindowStream.SetStream(m_x86ConvertOutStream);
RINOK(SetOutStreamSize(outSize));
CDecoderFlusher flusher(this);
const UInt64 start = m_OutWindowStream.GetProcessedSize();
for (;;)
{
UInt32 curSize = 1 << 18;
UInt64 rem = size - (m_OutWindowStream.GetProcessedSize() - start);
if (curSize > rem)
curSize = (UInt32)rem;
if (curSize == 0)
break;
RINOK(CodeSpec(curSize));
if (progress != NULL)
{
UInt64 inSize = m_InBitStream.GetProcessedSize();
UInt64 nowPos64 = m_OutWindowStream.GetProcessedSize() - start;
RINOK(progress->SetRatioInfo(&inSize, &nowPos64));
}
}
flusher.NeedFlush = false;
return Flush();
}
HRESULT CDecoder::Code(ISequentialInStream *inStream, ISequentialOutStream *outStream,
const UInt64 *inSize, const UInt64 *outSize, ICompressProgressInfo *progress)
{
try { return CodeReal(inStream, outStream, inSize, outSize, progress); }
catch(const CLzOutWindowException &e) { return e.ErrorCode; }
catch(...) { return S_FALSE; }
}
STDMETHODIMP CDecoder::SetInStream(ISequentialInStream *inStream)
{
m_InBitStream.SetStream(inStream);
return S_OK;
}
STDMETHODIMP CDecoder::ReleaseInStream()
{
m_InBitStream.ReleaseStream();
return S_OK;
}
STDMETHODIMP CDecoder::SetOutStreamSize(const UInt64 *outSize)
{
if (outSize == NULL)
return E_FAIL;
_remainLen = kLenIdNeedInit;
m_OutWindowStream.Init(_keepHistory);
return S_OK;
}
HRESULT CDecoder::SetParams(unsigned numDictBits)
{
if (numDictBits < kNumDictionaryBitsMin || numDictBits > kNumDictionaryBitsMax)
return E_INVALIDARG;
UInt32 numPosSlots;
if (numDictBits < 20)
numPosSlots = 30 + (numDictBits - 15) * 2;
else if (numDictBits == 20)
numPosSlots = 42;
else
numPosSlots = 50;
m_NumPosLenSlots = numPosSlots * kNumLenSlots;
if (!m_OutWindowStream.Create(kDictionarySizeMax))
return E_OUTOFMEMORY;
if (!m_InBitStream.Create(1 << 16))
return E_OUTOFMEMORY;
return S_OK;
}
}}