comparison src/zlib-1.2.7/contrib/dotzlib/DotZLib/Deflater.cs @ 4:e13257ea84a4

Add bzip2, zlib, liblo, portaudio sources

+//
+// © Copyright Henrik Ravn 2004
+//
+// Use, modification and distribution are subject to the Boost Software License, Version 1.0.
+// (See accompanying file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+using System;
+using System.Diagnostics;
+using System.Runtime.InteropServices;
+
+namespace DotZLib
+{
+
+    /// <summary>
+    /// Implements a data compressor, using the deflate algorithm in the ZLib dll
+    /// </summary>
+	public sealed class Deflater : CodecBase
+	{
+        #region Dll imports
+        [DllImport("ZLIB1.dll", CallingConvention=CallingConvention.Cdecl, CharSet=CharSet.Ansi)]
+        private static extern int deflateInit_(ref ZStream sz, int level, string vs, int size);
+
+        [DllImport("ZLIB1.dll", CallingConvention=CallingConvention.Cdecl)]
+        private static extern int deflate(ref ZStream sz, int flush);
+
+        [DllImport("ZLIB1.dll", CallingConvention=CallingConvention.Cdecl)]
+        private static extern int deflateReset(ref ZStream sz);
+
+        [DllImport("ZLIB1.dll", CallingConvention=CallingConvention.Cdecl)]
+        private static extern int deflateEnd(ref ZStream sz);
+        #endregion
+
+        /// <summary>
+        /// Constructs an new instance of the <c>Deflater</c>
+        /// </summary>
+        /// <param name="level">The compression level to use for this <c>Deflater</c></param>
+		public Deflater(CompressLevel level) : base()
+		{
+            int retval = deflateInit_(ref _ztream, (int)level, Info.Version, Marshal.SizeOf(_ztream));
+            if (retval != 0)
+                throw new ZLibException(retval, "Could not initialize deflater");
+
+            resetOutput();
+		}
+
+        /// <summary>
+        /// Adds more data to the codec to be processed.
+        /// </summary>
+        /// <param name="data">Byte array containing the data to be added to the codec</param>
+        /// <param name="offset">The index of the first byte to add from <c>data</c></param>
+        /// <param name="count">The number of bytes to add</param>
+        /// <remarks>Adding data may, or may not, raise the <c>DataAvailable</c> event</remarks>
+        public override void Add(byte[] data, int offset, int count)
+        {
+            if (data == null) throw new ArgumentNullException();
+            if (offset < 0 || count < 0) throw new ArgumentOutOfRangeException();
+            if ((offset+count) > data.Length) throw new ArgumentException();
+
+            int total = count;
+            int inputIndex = offset;
+            int err = 0;
+
+            while (err >= 0 && inputIndex < total)
+            {
+                copyInput(data, inputIndex, Math.Min(total - inputIndex, kBufferSize));
+                while (err >= 0 && _ztream.avail_in > 0)
+                {
+                    err = deflate(ref _ztream, (int)FlushTypes.None);
+                    if (err == 0)
+                        while (_ztream.avail_out == 0)
+                        {
+                            OnDataAvailable();
+                            err = deflate(ref _ztream, (int)FlushTypes.None);
+                        }
+                    inputIndex += (int)_ztream.total_in;
+                }
+            }
+            setChecksum( _ztream.adler );
+        }
+
+
+        /// <summary>
+        /// Finishes up any pending data that needs to be processed and handled.
+        /// </summary>
+        public override void Finish()
+        {
+            int err;
+            do
+            {
+                err = deflate(ref _ztream, (int)FlushTypes.Finish);
+                OnDataAvailable();
+            }
+            while (err == 0);
+            setChecksum( _ztream.adler );
+            deflateReset(ref _ztream);
+            resetOutput();
+        }
+
+        /// <summary>
+        /// Closes the internal zlib deflate stream
+        /// </summary>
+        protected override void CleanUp() { deflateEnd(ref _ztream); }
+
+    }
+}