diff options
Diffstat (limited to 'other-licenses/7zstub/src/Java/SevenZip/Compression/LZMA/Decoder.java')
| -rw-r--r-- | other-licenses/7zstub/src/Java/SevenZip/Compression/LZMA/Decoder.java | 329 |
1 files changed, 329 insertions, 0 deletions
diff --git a/other-licenses/7zstub/src/Java/SevenZip/Compression/LZMA/Decoder.java b/other-licenses/7zstub/src/Java/SevenZip/Compression/LZMA/Decoder.java new file mode 100644 index 000000000..4ebd57110 --- /dev/null +++ b/other-licenses/7zstub/src/Java/SevenZip/Compression/LZMA/Decoder.java @@ -0,0 +1,329 @@ +package SevenZip.Compression.LZMA;
+
+import SevenZip.Compression.RangeCoder.BitTreeDecoder;
+import SevenZip.Compression.LZMA.Base;
+import SevenZip.Compression.LZ.OutWindow;
+import java.io.IOException;
+
+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()
+ {
+ SevenZip.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(SevenZip.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()
+ {
+ SevenZip.Compression.RangeCoder.Decoder.InitBitModels(m_Decoders);
+ }
+
+ public byte DecodeNormal(SevenZip.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(SevenZip.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();
+ SevenZip.Compression.RangeCoder.Decoder m_RangeDecoder = new SevenZip.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);
+
+ SevenZip.Compression.RangeCoder.Decoder.InitBitModels(m_IsMatchDecoders);
+ SevenZip.Compression.RangeCoder.Decoder.InitBitModels(m_IsRep0LongDecoders);
+ SevenZip.Compression.RangeCoder.Decoder.InitBitModels(m_IsRepDecoders);
+ SevenZip.Compression.RangeCoder.Decoder.InitBitModels(m_IsRepG0Decoders);
+ SevenZip.Compression.RangeCoder.Decoder.InitBitModels(m_IsRepG1Decoders);
+ SevenZip.Compression.RangeCoder.Decoder.InitBitModels(m_IsRepG2Decoders);
+ SevenZip.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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