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// LzmaDecoder.cs↩
↩
using System;↩
↩
namespace SevenZip.Compression.LZMA↩
{↩
using RangeCoder;↩
↩
public class Decoder : ICoder, ISetDecoderProperties // ,System.IO.Stream↩
{↩
class LenDecoder↩
{↩
BitDecoder m_Choice = new BitDecoder();↩
BitDecoder m_Choice2 = new BitDecoder();↩
BitTreeDecoder[] m_LowCoder = new BitTreeDecoder[Base.kNumPosStatesMax];↩
BitTreeDecoder[] m_MidCoder = new BitTreeDecoder[Base.kNumPosStatesMax];↩
BitTreeDecoder m_HighCoder = new BitTreeDecoder(Base.kNumHighLenBits);↩
uint m_NumPosStates = 0;↩
↩
public void Create(uint numPosStates)↩
{↩
for (uint posState = m_NumPosStates; posState < numPosStates; posState++)↩
{↩
m_LowCoder[posState] = new BitTreeDecoder(Base.kNumLowLenBits);↩
m_MidCoder[posState] = new BitTreeDecoder(Base.kNumMidLenBits);↩
}↩
m_NumPosStates = numPosStates;↩
}↩
↩
public void Init()↩
{↩
m_Choice.Init();↩
for (uint posState = 0; posState < m_NumPosStates; posState++)↩
{↩
m_LowCoder[posState].Init();↩
m_MidCoder[posState].Init();↩
}↩
m_Choice2.Init();↩
m_HighCoder.Init();↩
}↩
↩
public uint Decode(RangeCoder.Decoder rangeDecoder, uint posState)↩
{↩
if (m_Choice.Decode(rangeDecoder) == 0)↩
return m_LowCoder[posState].Decode(rangeDecoder);↩
else↩
{↩
uint symbol = Base.kNumLowLenSymbols;↩
if (m_Choice2.Decode(rangeDecoder) == 0)↩
symbol += m_MidCoder[posState].Decode(rangeDecoder);↩
else↩
{↩
symbol += Base.kNumMidLenSymbols;↩
symbol += m_HighCoder.Decode(rangeDecoder);↩
}↩
return symbol;↩
}↩
}↩
}↩
↩
class LiteralDecoder↩
{↩
struct Decoder2↩
{↩
BitDecoder[] m_Decoders;↩
public void Create() { m_Decoders = new BitDecoder[0x300]; }↩
public void Init() { for (int i = 0; i < 0x300; i++) m_Decoders[i].Init(); }↩
↩
public byte DecodeNormal(RangeCoder.Decoder rangeDecoder)↩
{↩
uint symbol = 1;↩
do↩
symbol = (symbol << 1) | m_Decoders[symbol].Decode(rangeDecoder);↩
while (symbol < 0x100);↩
return (byte)symbol;↩
}↩
↩
public byte DecodeWithMatchByte(RangeCoder.Decoder rangeDecoder, byte matchByte)↩
{↩
uint symbol = 1;↩
do↩
{↩
uint matchBit = (uint)(matchByte >> 7) & 1;↩
matchByte <<= 1;↩
uint bit = m_Decoders[((1 + matchBit) << 8) + symbol].Decode(rangeDecoder);↩
symbol = (symbol << 1) | bit;↩
if (matchBit != bit)↩
{↩
while (symbol < 0x100)↩
symbol = (symbol << 1) | m_Decoders[symbol].Decode(rangeDecoder);↩
break;↩
}↩
}↩
while (symbol < 0x100);↩
return (byte)symbol;↩
}↩
}↩
↩
Decoder2[] m_Coders;↩
int m_NumPrevBits;↩
int m_NumPosBits;↩
uint m_PosMask;↩
↩
public void Create(int numPosBits, int numPrevBits)↩
{↩
if (m_Coders != null && m_NumPrevBits == numPrevBits &&↩
m_NumPosBits == numPosBits)↩
return;↩
m_NumPosBits = numPosBits;↩
m_PosMask = ((uint)1 << numPosBits) - 1;↩
m_NumPrevBits = numPrevBits;↩
uint numStates = (uint)1 << (m_NumPrevBits + m_NumPosBits);↩
m_Coders = new Decoder2[numStates];↩
for (uint i = 0; i < numStates; i++)↩
m_Coders[i].Create();↩
}↩
↩
public void Init()↩
{↩
uint numStates = (uint)1 << (m_NumPrevBits + m_NumPosBits);↩
for (uint i = 0; i < numStates; i++)↩
m_Coders[i].Init();↩
}↩
↩
uint GetState(uint pos, byte prevByte)↩
{ return ((pos & m_PosMask) << m_NumPrevBits) + (uint)(prevByte >> (8 - m_NumPrevBits)); }↩
↩
public byte DecodeNormal(RangeCoder.Decoder rangeDecoder, uint pos, byte prevByte)↩
{ return m_Coders[GetState(pos, prevByte)].DecodeNormal(rangeDecoder); }↩
↩
public byte DecodeWithMatchByte(RangeCoder.Decoder rangeDecoder, uint pos, byte prevByte, byte matchByte)↩
{ return m_Coders[GetState(pos, prevByte)].DecodeWithMatchByte(rangeDecoder, matchByte); }↩
};↩
↩
LZ.OutWindow m_OutWindow = new LZ.OutWindow();↩
RangeCoder.Decoder m_RangeDecoder = new RangeCoder.Decoder();↩
↩
BitDecoder[] m_IsMatchDecoders = new BitDecoder[Base.kNumStates << Base.kNumPosStatesBitsMax];↩
BitDecoder[] m_IsRepDecoders = new BitDecoder[Base.kNumStates];↩
BitDecoder[] m_IsRepG0Decoders = new BitDecoder[Base.kNumStates];↩
BitDecoder[] m_IsRepG1Decoders = new BitDecoder[Base.kNumStates];↩
BitDecoder[] m_IsRepG2Decoders = new BitDecoder[Base.kNumStates];↩
BitDecoder[] m_IsRep0LongDecoders = new BitDecoder[Base.kNumStates << Base.kNumPosStatesBitsMax];↩
↩
BitTreeDecoder[] m_PosSlotDecoder = new BitTreeDecoder[Base.kNumLenToPosStates];↩
BitDecoder[] m_PosDecoders = new BitDecoder[Base.kNumFullDistances - Base.kEndPosModelIndex];↩
↩
BitTreeDecoder m_PosAlignDecoder = new BitTreeDecoder(Base.kNumAlignBits);↩
↩
LenDecoder m_LenDecoder = new LenDecoder();↩
LenDecoder m_RepLenDecoder = new LenDecoder();↩
↩
LiteralDecoder m_LiteralDecoder = new LiteralDecoder();↩
↩
uint m_DictionarySize;↩
uint m_DictionarySizeCheck;↩
↩
uint m_PosStateMask;↩
↩
public Decoder()↩
{↩
m_DictionarySize = 0xFFFFFFFF;↩
for (int i = 0; i < Base.kNumLenToPosStates; i++)↩
m_PosSlotDecoder[i] = new BitTreeDecoder(Base.kNumPosSlotBits);↩
}↩
↩
void SetDictionarySize(uint dictionarySize)↩
{↩
if (m_DictionarySize != dictionarySize)↩
{↩
m_DictionarySize = dictionarySize;↩
m_DictionarySizeCheck = Math.Max(m_DictionarySize, 1);↩
uint blockSize = Math.Max(m_DictionarySizeCheck, (1 << 12));↩
m_OutWindow.Create(blockSize);↩
}↩
}↩
↩
void SetLiteralProperties(int lp, int lc)↩
{↩
if (lp > 8)↩
throw new InvalidParamException();↩
if (lc > 8)↩
throw new InvalidParamException();↩
m_LiteralDecoder.Create(lp, lc);↩
}↩
↩
void SetPosBitsProperties(int pb)↩
{↩
if (pb > Base.kNumPosStatesBitsMax)↩
throw new InvalidParamException();↩
uint numPosStates = (uint)1 << pb;↩
m_LenDecoder.Create(numPosStates);↩
m_RepLenDecoder.Create(numPosStates);↩
m_PosStateMask = numPosStates - 1;↩
}↩
↩
bool _solid = false;↩
void Init(System.IO.Stream inStream, System.IO.Stream outStream)↩
{↩
m_RangeDecoder.Init(inStream);↩
m_OutWindow.Init(outStream, _solid);↩
↩
uint i;↩
for (i = 0; i < Base.kNumStates; i++)↩
{↩
for (uint j = 0; j <= m_PosStateMask; j++)↩
{↩
uint index = (i << Base.kNumPosStatesBitsMax) + j;↩
m_IsMatchDecoders[index].Init();↩
m_IsRep0LongDecoders[index].Init();↩
}↩
m_IsRepDecoders[i].Init();↩
m_IsRepG0Decoders[i].Init();↩
m_IsRepG1Decoders[i].Init();↩
m_IsRepG2Decoders[i].Init();↩
}↩
↩
m_LiteralDecoder.Init();↩
for (i = 0; i < Base.kNumLenToPosStates; i++)↩
m_PosSlotDecoder[i].Init();↩
// m_PosSpecDecoder.Init();↩
for (i = 0; i < Base.kNumFullDistances - Base.kEndPosModelIndex; i++)↩
m_PosDecoders[i].Init();↩
↩
m_LenDecoder.Init();↩
m_RepLenDecoder.Init();↩
m_PosAlignDecoder.Init();↩
}↩
↩
public void Code(System.IO.Stream inStream, System.IO.Stream outStream,↩
Int64 inSize, Int64 outSize, ICodeProgress progress)↩
{↩
Init(inStream, outStream);↩
↩
Base.State state = new Base.State();↩
state.Init();↩
uint rep0 = 0, rep1 = 0, rep2 = 0, rep3 = 0;↩
↩
UInt64 nowPos64 = 0;↩
UInt64 outSize64 = (UInt64)outSize;↩
if (nowPos64 < outSize64)↩
{↩
if (m_IsMatchDecoders[state.Index << Base.kNumPosStatesBitsMax].Decode(m_RangeDecoder) != 0)↩
throw new DataErrorException();↩
state.UpdateChar();↩
byte b = m_LiteralDecoder.DecodeNormal(m_RangeDecoder, 0, 0);↩
m_OutWindow.PutByte(b);↩
nowPos64++;↩
}↩
while (nowPos64 < outSize64)↩
{↩
// UInt64 next = Math.Min(nowPos64 + (1 << 18), outSize64);↩
// while(nowPos64 < next)↩
{↩
uint posState = (uint)nowPos64 & m_PosStateMask;↩
if (m_IsMatchDecoders[(state.Index << Base.kNumPosStatesBitsMax) + posState].Decode(m_RangeDecoder) == 0)↩
{↩
byte b;↩
byte prevByte = m_OutWindow.GetByte(0);↩
if (!state.IsCharState())↩
b = m_LiteralDecoder.DecodeWithMatchByte(m_RangeDecoder,↩
(uint)nowPos64, prevByte, m_OutWindow.GetByte(rep0));↩
else↩
b = m_LiteralDecoder.DecodeNormal(m_RangeDecoder, (uint)nowPos64, prevByte);↩
m_OutWindow.PutByte(b);↩
state.UpdateChar();↩
nowPos64++;↩
}↩
else↩
{↩
uint len;↩
if (m_IsRepDecoders[state.Index].Decode(m_RangeDecoder) == 1)↩
{↩
if (m_IsRepG0Decoders[state.Index].Decode(m_RangeDecoder) == 0)↩
{↩
if (m_IsRep0LongDecoders[(state.Index << Base.kNumPosStatesBitsMax) + posState].Decode(m_RangeDecoder) == 0)↩
{↩
state.UpdateShortRep();↩
m_OutWindow.PutByte(m_OutWindow.GetByte(rep0));↩
nowPos64++;↩
continue;↩
}↩
}↩
else↩
{↩
UInt32 distance;↩
if (m_IsRepG1Decoders[state.Index].Decode(m_RangeDecoder) == 0)↩
{↩
distance = rep1;↩
}↩
else↩
{↩
if (m_IsRepG2Decoders[state.Index].Decode(m_RangeDecoder) == 0)↩
distance = rep2;↩
else↩
{↩
distance = rep3;↩
rep3 = rep2;↩
}↩
rep2 = rep1;↩
}↩
rep1 = rep0;↩
rep0 = distance;↩
}↩
len = m_RepLenDecoder.Decode(m_RangeDecoder, posState) + Base.kMatchMinLen;↩
state.UpdateRep();↩
}↩
else↩
{↩
rep3 = rep2;↩
rep2 = rep1;↩
rep1 = rep0;↩
len = Base.kMatchMinLen + m_LenDecoder.Decode(m_RangeDecoder, posState);↩
state.UpdateMatch();↩
uint posSlot = m_PosSlotDecoder[Base.GetLenToPosState(len)].Decode(m_RangeDecoder);↩
if (posSlot >= Base.kStartPosModelIndex)↩
{↩
int numDirectBits = (int)((posSlot >> 1) - 1);↩
rep0 = ((2 | (posSlot & 1)) << numDirectBits);↩
if (posSlot < Base.kEndPosModelIndex)↩
rep0 += BitTreeDecoder.ReverseDecode(m_PosDecoders,↩
rep0 - posSlot - 1, m_RangeDecoder, numDirectBits);↩
else↩
{↩
rep0 += (m_RangeDecoder.DecodeDirectBits(↩
numDirectBits - Base.kNumAlignBits) << Base.kNumAlignBits);↩
rep0 += m_PosAlignDecoder.ReverseDecode(m_RangeDecoder);↩
}↩
}↩
else↩
rep0 = posSlot;↩
}↩
if (rep0 >= m_OutWindow.TrainSize + nowPos64 || rep0 >= m_DictionarySizeCheck)↩
{↩
if (rep0 == 0xFFFFFFFF)↩
break;↩
throw new DataErrorException();↩
}↩
m_OutWindow.CopyBlock(rep0, len);↩
nowPos64 += len;↩
}↩
}↩
}↩
m_OutWindow.Flush();↩
m_OutWindow.ReleaseStream();↩
m_RangeDecoder.ReleaseStream();↩
}↩
↩
public void SetDecoderProperties(byte[] properties)↩
{↩
if (properties.Length < 5)↩
throw new InvalidParamException();↩
int lc = properties[0] % 9;↩
int remainder = properties[0] / 9;↩
int lp = remainder % 5;↩
int pb = remainder / 5;↩
if (pb > Base.kNumPosStatesBitsMax)↩
throw new InvalidParamException();↩
UInt32 dictionarySize = 0;↩
for (int i = 0; i < 4; i++)↩
dictionarySize += ((UInt32)(properties[1 + i])) << (i * 8);↩
SetDictionarySize(dictionarySize);↩
SetLiteralProperties(lp, lc);↩
SetPosBitsProperties(pb);↩
}↩
↩
public bool Train(System.IO.Stream stream)↩
{↩
_solid = true;↩
return m_OutWindow.Train(stream);↩
}↩
↩
/*↩
public override bool CanRead { get { return true; }}↩
public override bool CanWrite { get { return true; }}↩
public override bool CanSeek { get { return true; }}↩
public override long Length { get { return 0; }}↩
public override long Position↩
{↩
get { return 0; }↩
set { }↩
}↩
public override void Flush() { }↩
public override int Read(byte[] buffer, int offset, int count) ↩
{↩
return 0;↩
}↩
public override void Write(byte[] buffer, int offset, int count)↩
{↩
}↩
public override long Seek(long offset, System.IO.SeekOrigin origin)↩
{↩
return 0;↩
}↩
public override void SetLength(long value) {}↩
*/↩
}↩
}↩