summaryrefslogtreecommitdiffstats
path: root/CS/7zip/Compress/LZ/LzOutWindow.cs
diff options
context:
space:
mode:
Diffstat (limited to 'CS/7zip/Compress/LZ/LzOutWindow.cs')
-rwxr-xr-xCS/7zip/Compress/LZ/LzOutWindow.cs110
1 files changed, 110 insertions, 0 deletions
diff --git a/CS/7zip/Compress/LZ/LzOutWindow.cs b/CS/7zip/Compress/LZ/LzOutWindow.cs
new file mode 100755
index 0000000..84914f0
--- /dev/null
+++ b/CS/7zip/Compress/LZ/LzOutWindow.cs
@@ -0,0 +1,110 @@
+// LzOutWindow.cs
+
+namespace SevenZip.Compression.LZ
+{
+ public class OutWindow
+ {
+ byte[] _buffer = null;
+ uint _pos;
+ uint _windowSize = 0;
+ uint _streamPos;
+ System.IO.Stream _stream;
+
+ public uint TrainSize = 0;
+
+ public void Create(uint windowSize)
+ {
+ if (_windowSize != windowSize)
+ {
+ // System.GC.Collect();
+ _buffer = new byte[windowSize];
+ }
+ _windowSize = windowSize;
+ _pos = 0;
+ _streamPos = 0;
+ }
+
+ public void Init(System.IO.Stream stream, bool solid)
+ {
+ ReleaseStream();
+ _stream = stream;
+ if (!solid)
+ {
+ _streamPos = 0;
+ _pos = 0;
+ TrainSize = 0;
+ }
+ }
+
+ public bool Train(System.IO.Stream stream)
+ {
+ long len = stream.Length;
+ uint size = (len < _windowSize) ? (uint)len : _windowSize;
+ TrainSize = size;
+ stream.Position = len - size;
+ _streamPos = _pos = 0;
+ while (size > 0)
+ {
+ uint curSize = _windowSize - _pos;
+ if (size < curSize)
+ curSize = size;
+ int numReadBytes = stream.Read(_buffer, (int)_pos, (int)curSize);
+ if (numReadBytes == 0)
+ return false;
+ size -= (uint)numReadBytes;
+ _pos += (uint)numReadBytes;
+ _streamPos += (uint)numReadBytes;
+ if (_pos == _windowSize)
+ _streamPos = _pos = 0;
+ }
+ return true;
+ }
+
+ public void ReleaseStream()
+ {
+ Flush();
+ _stream = null;
+ }
+
+ public void Flush()
+ {
+ uint size = _pos - _streamPos;
+ if (size == 0)
+ return;
+ _stream.Write(_buffer, (int)_streamPos, (int)size);
+ if (_pos >= _windowSize)
+ _pos = 0;
+ _streamPos = _pos;
+ }
+
+ public void CopyBlock(uint distance, uint len)
+ {
+ uint pos = _pos - distance - 1;
+ if (pos >= _windowSize)
+ pos += _windowSize;
+ for (; len > 0; len--)
+ {
+ if (pos >= _windowSize)
+ pos = 0;
+ _buffer[_pos++] = _buffer[pos++];
+ if (_pos >= _windowSize)
+ Flush();
+ }
+ }
+
+ public void PutByte(byte b)
+ {
+ _buffer[_pos++] = b;
+ if (_pos >= _windowSize)
+ Flush();
+ }
+
+ public byte GetByte(uint distance)
+ {
+ uint pos = _pos - distance - 1;
+ if (pos >= _windowSize)
+ pos += _windowSize;
+ return _buffer[pos];
+ }
+ }
+}