misc/libphysfs/lzma/Java/SevenZip/Compression/LZ/BinTree.java
changeset 12213 bb5522e88ab2
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/misc/libphysfs/lzma/Java/SevenZip/Compression/LZ/BinTree.java	Mon Apr 10 12:06:43 2017 -0400
@@ -0,0 +1,382 @@
+// LZ.BinTree
+
+package SevenZip.Compression.LZ;
+import java.io.IOException;
+
+
+public class BinTree extends InWindow
+{
+	int _cyclicBufferPos;
+	int _cyclicBufferSize = 0;
+	int _matchMaxLen;
+	
+	int[] _son;
+	int[] _hash;
+	
+	int _cutValue = 0xFF;
+	int _hashMask;
+	int _hashSizeSum = 0;
+	
+	boolean HASH_ARRAY = true;
+
+	static final int kHash2Size = 1 << 10;
+	static final int kHash3Size = 1 << 16;
+	static final int kBT2HashSize = 1 << 16;
+	static final int kStartMaxLen = 1;
+	static final int kHash3Offset = kHash2Size;
+	static final int kEmptyHashValue = 0;
+	static final int kMaxValForNormalize = (1 << 30) - 1;
+	
+	int kNumHashDirectBytes = 0;
+	int kMinMatchCheck = 4;
+	int kFixHashSize = kHash2Size + kHash3Size;
+
+	public void SetType(int numHashBytes)
+	{
+		HASH_ARRAY = (numHashBytes > 2);
+		if (HASH_ARRAY)
+		{
+			kNumHashDirectBytes = 0;
+			kMinMatchCheck = 4;
+			kFixHashSize = kHash2Size + kHash3Size;
+		}
+		else
+		{
+			kNumHashDirectBytes = 2;
+			kMinMatchCheck = 2 + 1;
+			kFixHashSize = 0;
+		}
+	}
+	
+
+	
+
+	public void Init() throws IOException
+	{
+		super.Init();
+		for (int i = 0; i < _hashSizeSum; i++)
+			_hash[i] = kEmptyHashValue;
+		_cyclicBufferPos = 0;
+		ReduceOffsets(-1);
+	}
+	
+	public void MovePos() throws IOException
+	{
+		if (++_cyclicBufferPos >= _cyclicBufferSize)
+			_cyclicBufferPos = 0;
+		super.MovePos();
+		if (_pos == kMaxValForNormalize)
+			Normalize();
+	}
+	
+
+	
+	
+	
+	
+	
+	
+	public boolean Create(int historySize, int keepAddBufferBefore,
+			int matchMaxLen, int keepAddBufferAfter)
+	{
+		if (historySize > kMaxValForNormalize - 256)
+			return false;
+		_cutValue = 16 + (matchMaxLen >> 1);
+
+		int windowReservSize = (historySize + keepAddBufferBefore +
+				matchMaxLen + keepAddBufferAfter) / 2 + 256;
+		
+		super.Create(historySize + keepAddBufferBefore, matchMaxLen + keepAddBufferAfter, windowReservSize);
+		
+		_matchMaxLen = matchMaxLen;
+
+		int cyclicBufferSize = historySize + 1;
+		if (_cyclicBufferSize != cyclicBufferSize)
+			_son = new int[(_cyclicBufferSize = cyclicBufferSize) * 2];
+
+		int hs = kBT2HashSize;
+
+		if (HASH_ARRAY)
+		{
+			hs = historySize - 1;
+			hs |= (hs >> 1);
+			hs |= (hs >> 2);
+			hs |= (hs >> 4);
+			hs |= (hs >> 8);
+			hs >>= 1;
+			hs |= 0xFFFF;
+			if (hs > (1 << 24))
+				hs >>= 1;
+			_hashMask = hs;
+			hs++;
+			hs += kFixHashSize;
+		}
+		if (hs != _hashSizeSum)
+			_hash = new int [_hashSizeSum = hs];
+		return true;
+	}
+	public int GetMatches(int[] distances) throws IOException
+	{
+		int lenLimit;
+		if (_pos + _matchMaxLen <= _streamPos)
+			lenLimit = _matchMaxLen;
+		else
+		{
+			lenLimit = _streamPos - _pos;
+			if (lenLimit < kMinMatchCheck)
+			{
+				MovePos();
+				return 0;
+			}
+		}
+
+		int offset = 0;
+		int matchMinPos = (_pos > _cyclicBufferSize) ? (_pos - _cyclicBufferSize) : 0;
+		int cur = _bufferOffset + _pos;
+		int maxLen = kStartMaxLen; // to avoid items for len < hashSize;
+		int hashValue, hash2Value = 0, hash3Value = 0;
+		
+		if (HASH_ARRAY)
+		{
+			int temp = CrcTable[_bufferBase[cur] & 0xFF] ^ (_bufferBase[cur + 1] & 0xFF);
+			hash2Value = temp & (kHash2Size - 1);
+			temp ^= ((int)(_bufferBase[cur + 2] & 0xFF) << 8);
+			hash3Value = temp & (kHash3Size - 1);
+			hashValue = (temp ^ (CrcTable[_bufferBase[cur + 3] & 0xFF] << 5)) & _hashMask;
+		}
+		else
+			hashValue = ((_bufferBase[cur] & 0xFF) ^ ((int)(_bufferBase[cur + 1] & 0xFF) << 8));
+
+		int curMatch = _hash[kFixHashSize + hashValue];
+		if (HASH_ARRAY)
+		{
+			int curMatch2 = _hash[hash2Value];
+			int curMatch3 = _hash[kHash3Offset + hash3Value];
+			_hash[hash2Value] = _pos;
+			_hash[kHash3Offset + hash3Value] = _pos;
+			if (curMatch2 > matchMinPos)
+				if (_bufferBase[_bufferOffset + curMatch2] == _bufferBase[cur])
+				{
+					distances[offset++] = maxLen = 2;
+					distances[offset++] = _pos - curMatch2 - 1;
+				}
+			if (curMatch3 > matchMinPos)
+				if (_bufferBase[_bufferOffset + curMatch3] == _bufferBase[cur])
+				{
+					if (curMatch3 == curMatch2)
+						offset -= 2;
+					distances[offset++] = maxLen = 3;
+					distances[offset++] = _pos - curMatch3 - 1;
+					curMatch2 = curMatch3;
+				}
+			if (offset != 0 && curMatch2 == curMatch)
+			{
+				offset -= 2;
+				maxLen = kStartMaxLen;
+			}
+		}
+
+		_hash[kFixHashSize + hashValue] = _pos;
+
+		int ptr0 = (_cyclicBufferPos << 1) + 1;
+		int ptr1 = (_cyclicBufferPos << 1);
+
+		int len0, len1;
+		len0 = len1 = kNumHashDirectBytes;
+
+		if (kNumHashDirectBytes != 0)
+		{
+			if (curMatch > matchMinPos)
+			{
+				if (_bufferBase[_bufferOffset + curMatch + kNumHashDirectBytes] !=
+						_bufferBase[cur + kNumHashDirectBytes])
+				{
+					distances[offset++] = maxLen = kNumHashDirectBytes;
+					distances[offset++] = _pos - curMatch - 1;
+				}
+			}
+		}
+
+		int count = _cutValue;
+
+		while (true)
+		{
+			if (curMatch <= matchMinPos || count-- == 0)
+			{
+				_son[ptr0] = _son[ptr1] = kEmptyHashValue;
+				break;
+			}
+			int delta = _pos - curMatch;
+			int cyclicPos = ((delta <= _cyclicBufferPos) ?
+				(_cyclicBufferPos - delta) :
+				(_cyclicBufferPos - delta + _cyclicBufferSize)) << 1;
+
+			int pby1 = _bufferOffset + curMatch;
+			int len = Math.min(len0, len1);
+			if (_bufferBase[pby1 + len] == _bufferBase[cur + len])
+			{
+				while(++len != lenLimit)
+					if (_bufferBase[pby1 + len] != _bufferBase[cur + len])
+						break;
+				if (maxLen < len)
+				{
+					distances[offset++] = maxLen = len;
+					distances[offset++] = delta - 1;
+					if (len == lenLimit)
+					{
+						_son[ptr1] = _son[cyclicPos];
+						_son[ptr0] = _son[cyclicPos + 1];
+						break;
+					}
+				}
+			}
+			if ((_bufferBase[pby1 + len] & 0xFF) < (_bufferBase[cur + len] & 0xFF))
+			{
+				_son[ptr1] = curMatch;
+				ptr1 = cyclicPos + 1;
+				curMatch = _son[ptr1];
+				len1 = len;
+			}
+			else
+			{
+				_son[ptr0] = curMatch;
+				ptr0 = cyclicPos;
+				curMatch = _son[ptr0];
+				len0 = len;
+			}
+		}
+		MovePos();
+		return offset;
+	}
+
+	public void Skip(int num) throws IOException
+	{
+		do
+		{
+			int lenLimit;
+			if (_pos + _matchMaxLen <= _streamPos)
+			lenLimit = _matchMaxLen;
+			else
+			{
+				lenLimit = _streamPos - _pos;
+				if (lenLimit < kMinMatchCheck)
+				{
+					MovePos();
+					continue;
+				}
+			}
+
+			int matchMinPos = (_pos > _cyclicBufferSize) ? (_pos - _cyclicBufferSize) : 0;
+			int cur = _bufferOffset + _pos;
+			
+			int hashValue;
+
+			if (HASH_ARRAY)
+			{
+				int temp = CrcTable[_bufferBase[cur] & 0xFF] ^ (_bufferBase[cur + 1] & 0xFF);
+				int hash2Value = temp & (kHash2Size - 1);
+				_hash[hash2Value] = _pos;
+				temp ^= ((int)(_bufferBase[cur + 2] & 0xFF) << 8);
+				int hash3Value = temp & (kHash3Size - 1);
+				_hash[kHash3Offset + hash3Value] = _pos;
+				hashValue = (temp ^ (CrcTable[_bufferBase[cur + 3] & 0xFF] << 5)) & _hashMask;
+			}
+			else
+				hashValue = ((_bufferBase[cur] & 0xFF) ^ ((int)(_bufferBase[cur + 1] & 0xFF) << 8));
+
+			int curMatch = _hash[kFixHashSize + hashValue];
+			_hash[kFixHashSize + hashValue] = _pos;
+
+			int ptr0 = (_cyclicBufferPos << 1) + 1;
+			int ptr1 = (_cyclicBufferPos << 1);
+
+			int len0, len1;
+			len0 = len1 = kNumHashDirectBytes;
+
+			int count = _cutValue;
+			while (true)
+			{
+				if (curMatch <= matchMinPos || count-- == 0)
+				{
+					_son[ptr0] = _son[ptr1] = kEmptyHashValue;
+					break;
+				}
+
+				int delta = _pos - curMatch;
+				int cyclicPos = ((delta <= _cyclicBufferPos) ?
+					(_cyclicBufferPos - delta) :
+					(_cyclicBufferPos - delta + _cyclicBufferSize)) << 1;
+
+				int pby1 = _bufferOffset + curMatch;
+				int len = Math.min(len0, len1);
+				if (_bufferBase[pby1 + len] == _bufferBase[cur + len])
+				{
+					while (++len != lenLimit)
+						if (_bufferBase[pby1 + len] != _bufferBase[cur + len])
+							break;
+					if (len == lenLimit)
+					{
+						_son[ptr1] = _son[cyclicPos];
+						_son[ptr0] = _son[cyclicPos + 1];
+						break;
+					}
+				}
+				if ((_bufferBase[pby1 + len] & 0xFF) < (_bufferBase[cur + len] & 0xFF))
+				{
+					_son[ptr1] = curMatch;
+					ptr1 = cyclicPos + 1;
+					curMatch = _son[ptr1];
+					len1 = len;
+				}
+				else
+				{
+					_son[ptr0] = curMatch;
+					ptr0 = cyclicPos;
+					curMatch = _son[ptr0];
+					len0 = len;
+				}
+			}
+			MovePos();
+		}
+		while (--num != 0);
+	}
+	
+	void NormalizeLinks(int[] items, int numItems, int subValue)
+	{
+		for (int i = 0; i < numItems; i++)
+		{
+			int value = items[i];
+			if (value <= subValue)
+				value = kEmptyHashValue;
+			else
+				value -= subValue;
+			items[i] = value;
+		}
+	}
+	
+	void Normalize()
+	{
+		int subValue = _pos - _cyclicBufferSize;
+		NormalizeLinks(_son, _cyclicBufferSize * 2, subValue);
+		NormalizeLinks(_hash, _hashSizeSum, subValue);
+		ReduceOffsets(subValue);
+	}
+	
+	public void SetCutValue(int cutValue) { _cutValue = cutValue; }
+
+	private static final int[] CrcTable = new int[256];
+
+	static
+	{
+		for (int i = 0; i < 256; i++)
+		{
+			int r = i;
+			for (int j = 0; j < 8; j++)
+				if ((r & 1) != 0)
+					r = (r >>> 1) ^ 0xEDB88320;
+				else
+					r >>>= 1;
+			CrcTable[i] = r;
+		}
+	}
+}