com.badlogic.gdx.utils.compression.lzma.Decoder Maven / Gradle / Ivy
/*******************************************************************************
* Copyright 2011 See AUTHORS file.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
******************************************************************************/
package com.badlogic.gdx.utils.compression.lzma;
import java.io.IOException;
import com.badlogic.gdx.utils.compression.lz.OutWindow;
import com.badlogic.gdx.utils.compression.rangecoder.BitTreeDecoder;
public class Decoder {
class LenDecoder {
short[] m_Choice = new short[2];
BitTreeDecoder[] m_LowCoder = new BitTreeDecoder[Base.kNumPosStatesMax];
BitTreeDecoder[] m_MidCoder = new BitTreeDecoder[Base.kNumPosStatesMax];
BitTreeDecoder m_HighCoder = new BitTreeDecoder(Base.kNumHighLenBits);
int m_NumPosStates = 0;
public void Create (int numPosStates) {
for (; m_NumPosStates < numPosStates; m_NumPosStates++) {
m_LowCoder[m_NumPosStates] = new BitTreeDecoder(Base.kNumLowLenBits);
m_MidCoder[m_NumPosStates] = new BitTreeDecoder(Base.kNumMidLenBits);
}
}
public void Init () {
com.badlogic.gdx.utils.compression.rangecoder.Decoder.InitBitModels(m_Choice);
for (int posState = 0; posState < m_NumPosStates; posState++) {
m_LowCoder[posState].Init();
m_MidCoder[posState].Init();
}
m_HighCoder.Init();
}
public int Decode (com.badlogic.gdx.utils.compression.rangecoder.Decoder rangeDecoder, int posState) throws IOException {
if (rangeDecoder.DecodeBit(m_Choice, 0) == 0) return m_LowCoder[posState].Decode(rangeDecoder);
int symbol = Base.kNumLowLenSymbols;
if (rangeDecoder.DecodeBit(m_Choice, 1) == 0)
symbol += m_MidCoder[posState].Decode(rangeDecoder);
else
symbol += Base.kNumMidLenSymbols + m_HighCoder.Decode(rangeDecoder);
return symbol;
}
}
class LiteralDecoder {
class Decoder2 {
short[] m_Decoders = new short[0x300];
public void Init () {
com.badlogic.gdx.utils.compression.rangecoder.Decoder.InitBitModels(m_Decoders);
}
public byte DecodeNormal (com.badlogic.gdx.utils.compression.rangecoder.Decoder rangeDecoder) throws IOException {
int symbol = 1;
do
symbol = (symbol << 1) | rangeDecoder.DecodeBit(m_Decoders, symbol);
while (symbol < 0x100);
return (byte)symbol;
}
public byte DecodeWithMatchByte (com.badlogic.gdx.utils.compression.rangecoder.Decoder rangeDecoder, byte matchByte)
throws IOException {
int symbol = 1;
do {
int matchBit = (matchByte >> 7) & 1;
matchByte <<= 1;
int bit = rangeDecoder.DecodeBit(m_Decoders, ((1 + matchBit) << 8) + symbol);
symbol = (symbol << 1) | bit;
if (matchBit != bit) {
while (symbol < 0x100)
symbol = (symbol << 1) | rangeDecoder.DecodeBit(m_Decoders, symbol);
break;
}
} while (symbol < 0x100);
return (byte)symbol;
}
}
Decoder2[] m_Coders;
int m_NumPrevBits;
int m_NumPosBits;
int 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 = (1 << numPosBits) - 1;
m_NumPrevBits = numPrevBits;
int numStates = 1 << (m_NumPrevBits + m_NumPosBits);
m_Coders = new Decoder2[numStates];
for (int i = 0; i < numStates; i++)
m_Coders[i] = new Decoder2();
}
public void Init () {
int numStates = 1 << (m_NumPrevBits + m_NumPosBits);
for (int i = 0; i < numStates; i++)
m_Coders[i].Init();
}
Decoder2 GetDecoder (int pos, byte prevByte) {
return m_Coders[((pos & m_PosMask) << m_NumPrevBits) + ((prevByte & 0xFF) >>> (8 - m_NumPrevBits))];
}
}
OutWindow m_OutWindow = new OutWindow();
com.badlogic.gdx.utils.compression.rangecoder.Decoder m_RangeDecoder = new com.badlogic.gdx.utils.compression.rangecoder.Decoder();
short[] m_IsMatchDecoders = new short[Base.kNumStates << Base.kNumPosStatesBitsMax];
short[] m_IsRepDecoders = new short[Base.kNumStates];
short[] m_IsRepG0Decoders = new short[Base.kNumStates];
short[] m_IsRepG1Decoders = new short[Base.kNumStates];
short[] m_IsRepG2Decoders = new short[Base.kNumStates];
short[] m_IsRep0LongDecoders = new short[Base.kNumStates << Base.kNumPosStatesBitsMax];
BitTreeDecoder[] m_PosSlotDecoder = new BitTreeDecoder[Base.kNumLenToPosStates];
short[] m_PosDecoders = new short[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();
int m_DictionarySize = -1;
int m_DictionarySizeCheck = -1;
int m_PosStateMask;
public Decoder () {
for (int i = 0; i < Base.kNumLenToPosStates; i++)
m_PosSlotDecoder[i] = new BitTreeDecoder(Base.kNumPosSlotBits);
}
boolean SetDictionarySize (int dictionarySize) {
if (dictionarySize < 0) return false;
if (m_DictionarySize != dictionarySize) {
m_DictionarySize = dictionarySize;
m_DictionarySizeCheck = Math.max(m_DictionarySize, 1);
m_OutWindow.Create(Math.max(m_DictionarySizeCheck, (1 << 12)));
}
return true;
}
boolean SetLcLpPb (int lc, int lp, int pb) {
if (lc > Base.kNumLitContextBitsMax || lp > 4 || pb > Base.kNumPosStatesBitsMax) return false;
m_LiteralDecoder.Create(lp, lc);
int numPosStates = 1 << pb;
m_LenDecoder.Create(numPosStates);
m_RepLenDecoder.Create(numPosStates);
m_PosStateMask = numPosStates - 1;
return true;
}
void Init () throws IOException {
m_OutWindow.Init(false);
com.badlogic.gdx.utils.compression.rangecoder.Decoder.InitBitModels(m_IsMatchDecoders);
com.badlogic.gdx.utils.compression.rangecoder.Decoder.InitBitModels(m_IsRep0LongDecoders);
com.badlogic.gdx.utils.compression.rangecoder.Decoder.InitBitModels(m_IsRepDecoders);
com.badlogic.gdx.utils.compression.rangecoder.Decoder.InitBitModels(m_IsRepG0Decoders);
com.badlogic.gdx.utils.compression.rangecoder.Decoder.InitBitModels(m_IsRepG1Decoders);
com.badlogic.gdx.utils.compression.rangecoder.Decoder.InitBitModels(m_IsRepG2Decoders);
com.badlogic.gdx.utils.compression.rangecoder.Decoder.InitBitModels(m_PosDecoders);
m_LiteralDecoder.Init();
int i;
for (i = 0; i < Base.kNumLenToPosStates; i++)
m_PosSlotDecoder[i].Init();
m_LenDecoder.Init();
m_RepLenDecoder.Init();
m_PosAlignDecoder.Init();
m_RangeDecoder.Init();
}
public boolean Code (java.io.InputStream inStream, java.io.OutputStream outStream, long outSize) throws IOException {
m_RangeDecoder.SetStream(inStream);
m_OutWindow.SetStream(outStream);
Init();
int state = Base.StateInit();
int rep0 = 0, rep1 = 0, rep2 = 0, rep3 = 0;
long nowPos64 = 0;
byte prevByte = 0;
while (outSize < 0 || nowPos64 < outSize) {
int posState = (int)nowPos64 & m_PosStateMask;
if (m_RangeDecoder.DecodeBit(m_IsMatchDecoders, (state << Base.kNumPosStatesBitsMax) + posState) == 0) {
LiteralDecoder.Decoder2 decoder2 = m_LiteralDecoder.GetDecoder((int)nowPos64, prevByte);
if (!Base.StateIsCharState(state))
prevByte = decoder2.DecodeWithMatchByte(m_RangeDecoder, m_OutWindow.GetByte(rep0));
else
prevByte = decoder2.DecodeNormal(m_RangeDecoder);
m_OutWindow.PutByte(prevByte);
state = Base.StateUpdateChar(state);
nowPos64++;
} else {
int len;
if (m_RangeDecoder.DecodeBit(m_IsRepDecoders, state) == 1) {
len = 0;
if (m_RangeDecoder.DecodeBit(m_IsRepG0Decoders, state) == 0) {
if (m_RangeDecoder.DecodeBit(m_IsRep0LongDecoders, (state << Base.kNumPosStatesBitsMax) + posState) == 0) {
state = Base.StateUpdateShortRep(state);
len = 1;
}
} else {
int distance;
if (m_RangeDecoder.DecodeBit(m_IsRepG1Decoders, state) == 0)
distance = rep1;
else {
if (m_RangeDecoder.DecodeBit(m_IsRepG2Decoders, state) == 0)
distance = rep2;
else {
distance = rep3;
rep3 = rep2;
}
rep2 = rep1;
}
rep1 = rep0;
rep0 = distance;
}
if (len == 0) {
len = m_RepLenDecoder.Decode(m_RangeDecoder, posState) + Base.kMatchMinLen;
state = Base.StateUpdateRep(state);
}
} else {
rep3 = rep2;
rep2 = rep1;
rep1 = rep0;
len = Base.kMatchMinLen + m_LenDecoder.Decode(m_RangeDecoder, posState);
state = Base.StateUpdateMatch(state);
int posSlot = m_PosSlotDecoder[Base.GetLenToPosState(len)].Decode(m_RangeDecoder);
if (posSlot >= Base.kStartPosModelIndex) {
int numDirectBits = (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);
if (rep0 < 0) {
if (rep0 == -1) break;
return false;
}
}
} else
rep0 = posSlot;
}
if (rep0 >= nowPos64 || rep0 >= m_DictionarySizeCheck) {
// m_OutWindow.Flush();
return false;
}
m_OutWindow.CopyBlock(rep0, len);
nowPos64 += len;
prevByte = m_OutWindow.GetByte(0);
}
}
m_OutWindow.Flush();
m_OutWindow.ReleaseStream();
m_RangeDecoder.ReleaseStream();
return true;
}
public boolean SetDecoderProperties (byte[] properties) {
if (properties.length < 5) return false;
int val = properties[0] & 0xFF;
int lc = val % 9;
int remainder = val / 9;
int lp = remainder % 5;
int pb = remainder / 5;
int dictionarySize = 0;
for (int i = 0; i < 4; i++)
dictionarySize += ((int)(properties[1 + i]) & 0xFF) << (i * 8);
if (!SetLcLpPb(lc, lp, pb)) return false;
return SetDictionarySize(dictionarySize);
}
}
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