Move zlib to top-level root.

[ira/wip.git] / lib / zlib / contrib / dotzlib / DotZLib / CircularBuffer.cs

diff --git a/lib/zlib/contrib/dotzlib/DotZLib/CircularBuffer.cs b/lib/zlib/contrib/dotzlib/DotZLib/CircularBuffer.cs
new file mode 100644 (file)
index 0000000..16997e9
--- /dev/null
+++ b/lib/zlib/contrib/dotzlib/DotZLib/CircularBuffer.cs
@@ -0,0 +1,83 @@
+//\r
+// © Copyright Henrik Ravn 2004\r
+//\r
+// Use, modification and distribution are subject to the Boost Software License, Version 1.0. \r
+// (See accompanying file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)\r
+//\r
+\r
+using System;\r
+using System.Diagnostics;\r
+\r
+namespace DotZLib\r
+{\r
+\r
+       /// <summary>\r
+       /// This class implements a circular buffer\r
+       /// </summary>\r
+       internal class CircularBuffer\r
+       {\r
+        #region Private data\r
+        private int _capacity;\r
+        private int _head;\r
+        private int _tail;\r
+        private int _size;\r
+        private byte[] _buffer;\r
+        #endregion\r
+\r
+        public CircularBuffer(int capacity)\r
+        {    \r
+            Debug.Assert( capacity > 0 );\r
+            _buffer = new byte[capacity];\r
+            _capacity = capacity;\r
+            _head = 0;\r
+            _tail = 0;\r
+            _size = 0;\r
+        }\r
+\r
+        public int Size { get { return _size; } }\r
+\r
+        public int Put(byte[] source, int offset, int count)\r
+        {\r
+            Debug.Assert( count > 0 );\r
+            int trueCount = Math.Min(count, _capacity - Size);\r
+            for (int i = 0; i < trueCount; ++i)\r
+                _buffer[(_tail+i) % _capacity] = source[offset+i];\r
+            _tail += trueCount;\r
+            _tail %= _capacity;\r
+            _size += trueCount;\r
+            return trueCount;\r
+        }\r
+\r
+        public bool Put(byte b)\r
+        {\r
+            if (Size == _capacity) // no room\r
+                return false;\r
+            _buffer[_tail++] = b;\r
+            _tail %= _capacity;\r
+            ++_size;\r
+            return true;\r
+        }\r
+\r
+        public int Get(byte[] destination, int offset, int count)\r
+        {\r
+            int trueCount = Math.Min(count,Size);\r
+            for (int i = 0; i < trueCount; ++i)\r
+                destination[offset + i] = _buffer[(_head+i) % _capacity];\r
+            _head += trueCount;\r
+            _head %= _capacity;\r
+            _size -= trueCount;\r
+            return trueCount;\r
+        }\r
+\r
+        public int Get()\r
+        {\r
+            if (Size == 0)\r
+                return -1;\r
+\r
+            int result = (int)_buffer[_head++ % _capacity];\r
+            --_size;\r
+            return result;\r
+        }\r
+\r
+    }\r
+}\r