--- /dev/null
+// 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;
+ }
+ }
+}
projects / physicsfs / blobdiff