p7zip-rar/CPP/7zip/Compress/Rar2Decoder.cpp
2017-10-11 12:40:22 +02:00

402 lines
9.9 KiB
C++

// Rar2Decoder.cpp
// According to unRAR license, this code may not be used to develop
// a program that creates RAR archives
#include "StdAfx.h"
#include "Rar2Decoder.h"
namespace NCompress {
namespace NRar2 {
namespace NMultimedia {
Byte CFilter::Decode(int &channelDelta, Byte deltaByte)
{
D4 = D3;
D3 = D2;
D2 = LastDelta - D1;
D1 = LastDelta;
int predictedValue = ((8 * LastChar + K1 * D1 + K2 * D2 + K3 * D3 + K4 * D4 + K5 * channelDelta) >> 3);
Byte realValue = (Byte)(predictedValue - deltaByte);
{
int i = ((int)(signed char)deltaByte) << 3;
Dif[0] += abs(i);
Dif[1] += abs(i - D1);
Dif[2] += abs(i + D1);
Dif[3] += abs(i - D2);
Dif[4] += abs(i + D2);
Dif[5] += abs(i - D3);
Dif[6] += abs(i + D3);
Dif[7] += abs(i - D4);
Dif[8] += abs(i + D4);
Dif[9] += abs(i - channelDelta);
Dif[10] += abs(i + channelDelta);
}
channelDelta = LastDelta = (signed char)(realValue - LastChar);
LastChar = realValue;
if (((++ByteCount) & 0x1F) == 0)
{
UInt32 minDif = Dif[0];
UInt32 numMinDif = 0;
Dif[0] = 0;
for (unsigned i = 1; i < ARRAY_SIZE(Dif); i++)
{
if (Dif[i] < minDif)
{
minDif = Dif[i];
numMinDif = i;
}
Dif[i] = 0;
}
switch (numMinDif)
{
case 1: if (K1 >= -16) K1--; break;
case 2: if (K1 < 16) K1++; break;
case 3: if (K2 >= -16) K2--; break;
case 4: if (K2 < 16) K2++; break;
case 5: if (K3 >= -16) K3--; break;
case 6: if (K3 < 16) K3++; break;
case 7: if (K4 >= -16) K4--; break;
case 8: if (K4 < 16) K4++; break;
case 9: if (K5 >= -16) K5--; break;
case 10:if (K5 < 16) K5++; break;
}
}
return realValue;
}
}
static const UInt32 kHistorySize = 1 << 20;
static const UInt32 kWindowReservSize = (1 << 22) + 256;
CDecoder::CDecoder():
m_IsSolid(false)
{
}
void CDecoder::InitStructures()
{
m_MmFilter.Init();
for (unsigned i = 0; i < kNumRepDists; i++)
m_RepDists[i] = 0;
m_RepDistPtr = 0;
m_LastLength = 0;
memset(m_LastLevels, 0, kMaxTableSize);
}
UInt32 CDecoder::ReadBits(unsigned numBits) { return m_InBitStream.ReadBits(numBits); }
#define RIF(x) { if (!(x)) return false; }
bool CDecoder::ReadTables(void)
{
Byte levelLevels[kLevelTableSize];
Byte newLevels[kMaxTableSize];
m_AudioMode = (ReadBits(1) == 1);
if (ReadBits(1) == 0)
memset(m_LastLevels, 0, kMaxTableSize);
unsigned numLevels;
if (m_AudioMode)
{
m_NumChannels = ReadBits(2) + 1;
if (m_MmFilter.CurrentChannel >= m_NumChannels)
m_MmFilter.CurrentChannel = 0;
numLevels = m_NumChannels * kMMTableSize;
}
else
numLevels = kHeapTablesSizesSum;
unsigned i;
for (i = 0; i < kLevelTableSize; i++)
levelLevels[i] = (Byte)ReadBits(4);
RIF(m_LevelDecoder.Build(levelLevels));
i = 0;
while (i < numLevels)
{
UInt32 sym = m_LevelDecoder.Decode(&m_InBitStream);
if (sym < kTableDirectLevels)
{
newLevels[i] = (Byte)((sym + m_LastLevels[i]) & kLevelMask);
i++;
}
else
{
if (sym == kTableLevelRepNumber)
{
unsigned t = ReadBits(2) + 3;
for (unsigned reps = t; reps > 0 && i < numLevels; reps--, i++)
newLevels[i] = newLevels[i - 1];
}
else
{
unsigned num;
if (sym == kTableLevel0Number)
num = ReadBits(3) + 3;
else if (sym == kTableLevel0Number2)
num = ReadBits(7) + 11;
else
return false;
for (; num > 0 && i < numLevels; num--)
newLevels[i++] = 0;
}
}
}
if (m_AudioMode)
for (i = 0; i < m_NumChannels; i++)
{
RIF(m_MMDecoders[i].Build(&newLevels[i * kMMTableSize]));
}
else
{
RIF(m_MainDecoder.Build(&newLevels[0]));
RIF(m_DistDecoder.Build(&newLevels[kMainTableSize]));
RIF(m_LenDecoder.Build(&newLevels[kMainTableSize + kDistTableSize]));
}
memcpy(m_LastLevels, newLevels, kMaxTableSize);
return true;
}
bool CDecoder::ReadLastTables()
{
// it differs a little from pure RAR sources;
// UInt64 ttt = m_InBitStream.GetProcessedSize() + 2;
// + 2 works for: return 0xFF; in CInBuffer::ReadByte.
if (m_InBitStream.GetProcessedSize() + 7 <= m_PackSize) // test it: probably incorrect;
// if (m_InBitStream.GetProcessedSize() + 2 <= m_PackSize) // test it: probably incorrect;
if (m_AudioMode)
{
UInt32 symbol = m_MMDecoders[m_MmFilter.CurrentChannel].Decode(&m_InBitStream);
if (symbol == 256)
return ReadTables();
if (symbol >= kMMTableSize)
return false;
}
else
{
UInt32 sym = m_MainDecoder.Decode(&m_InBitStream);
if (sym == kReadTableNumber)
return ReadTables();
if (sym >= kMainTableSize)
return false;
}
return true;
}
/*
class CCoderReleaser
{
CDecoder *m_Coder;
public:
CCoderReleaser(CDecoder *coder): m_Coder(coder) {}
~CCoderReleaser()
{
m_Coder->ReleaseStreams();
}
};
*/
bool CDecoder::DecodeMm(UInt32 pos)
{
while (pos-- > 0)
{
UInt32 symbol = m_MMDecoders[m_MmFilter.CurrentChannel].Decode(&m_InBitStream);
if (symbol == 256)
return true;
if (symbol >= kMMTableSize)
return false;
/*
Byte byPredict = m_Predictor.Predict();
Byte byReal = (Byte)(byPredict - (Byte)symbol);
m_Predictor.Update(byReal, byPredict);
*/
Byte byReal = m_MmFilter.Decode((Byte)symbol);
m_OutWindowStream.PutByte(byReal);
if (++m_MmFilter.CurrentChannel == m_NumChannels)
m_MmFilter.CurrentChannel = 0;
}
return true;
}
bool CDecoder::DecodeLz(Int32 pos)
{
while (pos > 0)
{
UInt32 sym = m_MainDecoder.Decode(&m_InBitStream);
UInt32 length, distance;
if (sym < 256)
{
m_OutWindowStream.PutByte(Byte(sym));
pos--;
continue;
}
else if (sym >= kMatchNumber)
{
sym -= kMatchNumber;
length = kNormalMatchMinLen + UInt32(kLenStart[sym]) +
m_InBitStream.ReadBits(kLenDirectBits[sym]);
sym = m_DistDecoder.Decode(&m_InBitStream);
if (sym >= kDistTableSize)
return false;
distance = kDistStart[sym] + m_InBitStream.ReadBits(kDistDirectBits[sym]);
if (distance >= kDistLimit3)
{
length += 2 - ((distance - kDistLimit4) >> 31);
// length++;
// if (distance >= kDistLimit4)
// length++;
}
}
else if (sym == kRepBothNumber)
{
length = m_LastLength;
if (length == 0)
return false;
distance = m_RepDists[(m_RepDistPtr + 4 - 1) & 3];
}
else if (sym < kLen2Number)
{
distance = m_RepDists[(m_RepDistPtr - (sym - kRepNumber + 1)) & 3];
sym = m_LenDecoder.Decode(&m_InBitStream);
if (sym >= kLenTableSize)
return false;
length = 2 + kLenStart[sym] + m_InBitStream.ReadBits(kLenDirectBits[sym]);
if (distance >= kDistLimit2)
{
length++;
if (distance >= kDistLimit3)
{
length += 2 - ((distance - kDistLimit4) >> 31);
// length++;
// if (distance >= kDistLimit4)
// length++;
}
}
}
else if (sym < kReadTableNumber)
{
sym -= kLen2Number;
distance = kLen2DistStarts[sym] +
m_InBitStream.ReadBits(kLen2DistDirectBits[sym]);
length = 2;
}
else if (sym == kReadTableNumber)
return true;
else
return false;
m_RepDists[m_RepDistPtr++ & 3] = distance;
m_LastLength = length;
if (!m_OutWindowStream.CopyBlock(distance, length))
return false;
pos -= length;
}
return true;
}
HRESULT CDecoder::CodeReal(ISequentialInStream *inStream, ISequentialOutStream *outStream,
const UInt64 *inSize, const UInt64 *outSize, ICompressProgressInfo *progress)
{
if (inSize == NULL || outSize == NULL)
return E_INVALIDARG;
if (!m_OutWindowStream.Create(kHistorySize))
return E_OUTOFMEMORY;
if (!m_InBitStream.Create(1 << 20))
return E_OUTOFMEMORY;
m_PackSize = *inSize;
UInt64 pos = 0, unPackSize = *outSize;
m_OutWindowStream.SetStream(outStream);
m_OutWindowStream.Init(m_IsSolid);
m_InBitStream.SetStream(inStream);
m_InBitStream.Init();
// CCoderReleaser coderReleaser(this);
if (!m_IsSolid)
{
InitStructures();
if (unPackSize == 0)
{
if (m_InBitStream.GetProcessedSize() + 2 <= m_PackSize) // test it: probably incorrect;
if (!ReadTables())
return S_FALSE;
return S_OK;
}
if (!ReadTables())
return S_FALSE;
}
UInt64 startPos = m_OutWindowStream.GetProcessedSize();
while (pos < unPackSize)
{
UInt32 blockSize = 1 << 20;
if (blockSize > unPackSize - pos)
blockSize = (UInt32)(unPackSize - pos);
UInt64 blockStartPos = m_OutWindowStream.GetProcessedSize();
if (m_AudioMode)
{
if (!DecodeMm(blockSize))
return S_FALSE;
}
else
{
if (!DecodeLz((Int32)blockSize))
return S_FALSE;
}
UInt64 globalPos = m_OutWindowStream.GetProcessedSize();
pos = globalPos - blockStartPos;
if (pos < blockSize)
if (!ReadTables())
return S_FALSE;
pos = globalPos - startPos;
if (progress != 0)
{
UInt64 packSize = m_InBitStream.GetProcessedSize();
RINOK(progress->SetRatioInfo(&packSize, &pos));
}
}
if (pos > unPackSize)
return S_FALSE;
if (!ReadLastTables())
return S_FALSE;
return m_OutWindowStream.Flush();
}
STDMETHODIMP CDecoder::Code(ISequentialInStream *inStream, ISequentialOutStream *outStream,
const UInt64 *inSize, const UInt64 *outSize, ICompressProgressInfo *progress)
{
try { return CodeReal(inStream, outStream, inSize, outSize, progress); }
catch(const CInBufferException &e) { return e.ErrorCode; }
catch(const CLzOutWindowException &e) { return e.ErrorCode; }
catch(...) { return S_FALSE; }
}
STDMETHODIMP CDecoder::SetDecoderProperties2(const Byte *data, UInt32 size)
{
if (size < 1)
return E_INVALIDARG;
m_IsSolid = ((data[0] & 1) != 0);
return S_OK;
}
}}