1 files changed, 125 insertions, 0 deletions
diff --git a/SevenZip/sdk/Compress/LZ/LzOutWindow.cs b/SevenZip/sdk/Compress/LZ/LzOutWindow.cs
new file mode 100644
index 00000000..6cf788ad
--- /dev/null
+++ b/SevenZip/sdk/Compress/LZ/LzOutWindow.cs
@@ -0,0 +1,125 @@
+/*  This file is part of SevenZipSharp.
+
+    SevenZipSharp is free software: you can redistribute it and/or modify
+    it under the terms of the GNU Lesser General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    SevenZipSharp is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU Lesser General Public License for more details.
+
+    You should have received a copy of the GNU Lesser General Public License
+    along with SevenZipSharp.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+using System.IO;
+
+namespace SevenZip.Sdk.Compression.LZ
+{
+    internal class OutWindow
+    {
+        private byte[] _buffer;
+        private uint _pos;
+        private Stream _stream;
+        private uint _streamPos;
+        private uint _windowSize;
+        public uint TrainSize;
+
+        public void Create(uint windowSize)
+        {
+            if (_windowSize != windowSize)
+            {
+                // System.GC.Collect();
+                _buffer = new byte[windowSize];
+            }
+            _windowSize = windowSize;
+            _pos = 0;
+            _streamPos = 0;
+        }
+
+        public void Init(Stream stream, bool solid)
+        {
+            ReleaseStream();
+            _stream = stream;
+            if (!solid)
+            {
+                _streamPos = 0;
+                _pos = 0;
+                TrainSize = 0;
+            }
+        }
+
+        public bool Train(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];
+        }
+    }
+}
+\ No newline at end of file