Files
easy7zip/7zip/Compress/Deflate/DeflateDecoder.cpp
Igor Pavlov d66cf2fcf3 4.27 beta
2016-05-28 00:15:44 +01:00

341 lines
8.9 KiB
C++
Executable File

// DeflateDecoder.cpp
#include "StdAfx.h"
#include "DeflateDecoder.h"
namespace NCompress {
namespace NDeflate {
namespace NDecoder {
const int kLenIdFinished = -1;
const int kLenIdNeedInit = -2;
CCoder::CCoder(bool deflate64Mode): _deflate64Mode(deflate64Mode), _keepHistory(false) {}
void CCoder::DeCodeLevelTable(Byte *newLevels, int numLevels)
{
int i = 0;
while (i < numLevels)
{
UInt32 number = m_LevelDecoder.DecodeSymbol(&m_InBitStream);
if (number < kTableDirectLevels)
newLevels[i++] = Byte(number);
else
{
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];
}
else
{
int num;
if (number == kTableLevel0Number)
num = m_InBitStream.ReadBits(3) + 3;
else
num = m_InBitStream.ReadBits(7) + 11;
for (;num > 0 && i < numLevels; num--)
newLevels[i++] = 0;
}
}
}
}
#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);
if (blockType > NBlockType::kDynamicHuffman)
return false;
if (blockType == NBlockType::kStored)
{
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);
}
m_StoredMode = false;
Byte litLenLevels[kStaticMainTableSize];
Byte distLevels[kStaticDistTableSize];
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;
}
else // (blockType == kDynamicHuffman)
{
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;
Byte levelLevels[kLevelTableSize];
for (int i = 0; i < kLevelTableSize; i++)
{
int position = kCodeLengthAlphabetOrder[i];
if(i < numLevelCodes)
levelLevels[position] = Byte(m_InBitStream.ReadBits(kDeflateLevelCodeFieldSize));
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);
}
RIF(m_MainDecoder.SetCodeLengths(litLenLevels));
return m_DistDecoder.SetCodeLengths(distLevels);
}
HRESULT CCoder::CodeSpec(UInt32 curSize)
{
if (_remainLen == kLenIdFinished)
return S_OK;
if (_remainLen == kLenIdNeedInit)
{
if (!_keepHistory)
{
if (!m_OutWindowStream.Create(_deflate64Mode ? kHistorySize64: kHistorySize32))
return E_OUTOFMEMORY;
}
if (!m_InBitStream.Create(1 << 17))
return E_OUTOFMEMORY;
m_OutWindowStream.Init(_keepHistory);
m_InBitStream.Init();
m_FinalBlock = false;
_remainLen = 0;
_needReadTable = true;
}
if (curSize == 0)
return S_OK;
while(_remainLen > 0 && curSize > 0)
{
_remainLen--;
Byte b = m_OutWindowStream.GetByte(_rep0);
m_OutWindowStream.PutByte(b);
curSize--;
}
while(curSize > 0)
{
if (_needReadTable)
{
if (m_FinalBlock)
{
_remainLen = kLenIdFinished;
break;
}
if (!ReadTables())
return S_FALSE;
_needReadTable = false;
}
if(m_StoredMode)
{
for (; m_StoredBlockSize > 0 && curSize > 0; m_StoredBlockSize--, curSize--)
m_OutWindowStream.PutByte((Byte)m_InBitStream.ReadBits(8));
_needReadTable = (m_StoredBlockSize == 0);
continue;
}
while(curSize > 0)
{
if (m_InBitStream.NumExtraBytes > 4)
return S_FALSE;
UInt32 number = m_MainDecoder.DecodeSymbol(&m_InBitStream);
if (number < 256)
{
m_OutWindowStream.PutByte((Byte)number);
curSize--;
continue;
}
else if (number >= kMatchNumber)
{
number -= kMatchNumber;
UInt32 len;
{
int numBits;
if (_deflate64Mode)
{
len = kLenStart64[number];
numBits = kLenDirectBits64[number];
}
else
{
len = kLenStart32[number];
numBits = kLenDirectBits32[number];
}
len += kMatchMinLen + m_InBitStream.ReadBits(numBits);
}
UInt32 locLen = len;
if (locLen > curSize)
locLen = (UInt32)curSize;
number = m_DistDecoder.DecodeSymbol(&m_InBitStream);
if (number >= kStaticDistTableSize)
return S_FALSE;
UInt32 distance = kDistStart[number] + m_InBitStream.ReadBits(kDistDirectBits[number]);
if (!m_OutWindowStream.CopyBlock(distance, locLen))
return S_FALSE;
curSize -= locLen;
len -= locLen;
if (len != 0)
{
_remainLen = (int)len;
_rep0 = distance;
break;
}
}
else if (number == kReadTableNumber)
{
_needReadTable = true;
break;
}
else
return S_FALSE;
}
}
return S_OK;
}
HRESULT CCoder::CodeReal(ISequentialInStream *inStream,
ISequentialOutStream *outStream,
const UInt64 *, const UInt64 *outSize,
ICompressProgressInfo *progress)
{
SetInStream(inStream);
m_OutWindowStream.SetStream(outStream);
SetOutStreamSize(outSize);
CCoderReleaser flusher(this);
const UInt64 start = m_OutWindowStream.GetProcessedSize();
while(true)
{
UInt32 curSize = 1 << 18;
if (outSize != 0)
{
const UInt64 rem = *outSize - (m_OutWindowStream.GetProcessedSize() - start);
if (curSize > rem)
curSize = (UInt32)rem;
}
if (curSize == 0)
break;
RINOK(CodeSpec(curSize));
if (_remainLen == kLenIdFinished)
break;
if (progress != NULL)
{
UInt64 inSize = m_InBitStream.GetProcessedSize();
UInt64 nowPos64 = m_OutWindowStream.GetProcessedSize() - start;
RINOK(progress->SetRatioInfo(&inSize, &nowPos64));
}
}
flusher.NeedFlush = false;
return Flush();
}
#ifdef _NO_EXCEPTIONS
#define DEFLATE_TRY_BEGIN
#define DEFLATE_TRY_END
#else
#define DEFLATE_TRY_BEGIN try {
#define DEFLATE_TRY_END } \
catch(const CInBufferException &e) { return e.ErrorCode; } \
catch(const CLZOutWindowException &e) { return e.ErrorCode; } \
catch(...) { return S_FALSE; }
#endif
HRESULT CCoder::Code(ISequentialInStream *inStream,
ISequentialOutStream *outStream, const UInt64 *inSize, const UInt64 *outSize,
ICompressProgressInfo *progress)
{
DEFLATE_TRY_BEGIN
return CodeReal(inStream, outStream, inSize, outSize, progress);
DEFLATE_TRY_END
}
STDMETHODIMP CCoder::GetInStreamProcessedSize(UInt64 *value)
{
if (value == NULL)
return E_INVALIDARG;
*value = m_InBitStream.GetProcessedSize();
return S_OK;
}
STDMETHODIMP CCoder::SetInStream(ISequentialInStream *inStream)
{
m_InBitStream.SetStream(inStream);
return S_OK;
}
STDMETHODIMP CCoder::ReleaseInStream()
{
m_InBitStream.ReleaseStream();
return S_OK;
}
STDMETHODIMP CCoder::SetOutStreamSize(const UInt64 *outSize)
{
_remainLen = kLenIdNeedInit;
m_OutWindowStream.Init(_keepHistory);
return S_OK;
}
#ifdef _ST_MODE
STDMETHODIMP CCoder::Read(void *data, UInt32 size, UInt32 *processedSize)
{
DEFLATE_TRY_BEGIN
if (processedSize)
*processedSize = 0;
const UInt64 startPos = m_OutWindowStream.GetProcessedSize();
m_OutWindowStream.SetMemStream((Byte *)data);
RINOK(CodeSpec(size));
if (processedSize)
*processedSize = (UInt32)(m_OutWindowStream.GetProcessedSize() - startPos);
return Flush();
DEFLATE_TRY_END
}
#endif
}}}