root / trunk / hammock / src / net35 / ICSharpCode.SharpZipLib.Silverlight / Zip / Compression / DeflaterEngine.cs @ 0eea575a
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// DeflaterEngine.cs |
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// |
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// Copyright (C) 2001 Mike Krueger |
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// Copyright (C) 2004 John Reilly |
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// |
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// This file was translated from java, it was part of the GNU Classpath |
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// Copyright (C) 2001 Free Software Foundation, Inc. |
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// |
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// This program is free software; you can redistribute it and/or |
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// modify it under the terms of the GNU General Public License |
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// as published by the Free Software Foundation; either version 2 |
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// of the License, or (at your option) any later version. |
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// |
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// This program is distributed in the hope that it will be useful, |
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// but WITHOUT ANY WARRANTY; without even the implied warranty of |
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// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
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// GNU General Public License for more details. |
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// |
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// You should have received a copy of the GNU General Public License |
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// along with this program; if not, write to the Free Software |
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// Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. |
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// |
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// Linking this library statically or dynamically with other modules is |
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// making a combined work based on this library. Thus, the terms and |
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// conditions of the GNU General Public License cover the whole |
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// combination. |
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// |
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// As a special exception, the copyright holders of this library give you |
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// permission to link this library with independent modules to produce an |
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// executable, regardless of the license terms of these independent |
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// modules, and to copy and distribute the resulting executable under |
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// terms of your choice, provided that you also meet, for each linked |
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// independent module, the terms and conditions of the license of that |
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// module. An independent module is a module which is not derived from |
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// or based on this library. If you modify this library, you may extend |
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// this exception to your version of the library, but you are not |
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// obligated to do so. If you do not wish to do so, delete this |
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// exception statement from your version. |
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|
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using System; |
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using ICSharpCode.SharpZipLib.Silverlight.Checksums; |
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using ICSharpCode.SharpZipLib.Silverlight.Zip.Compression; |
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|
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namespace ICSharpCode.SharpZipLib.Silverlight.Zip.Compression |
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{
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/// <summary> |
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/// Strategies for deflater |
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/// </summary> |
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public enum DeflateStrategy |
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{
|
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/// <summary> |
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/// The default strategy |
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/// </summary> |
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Default = 0, |
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|
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/// <summary> |
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/// This strategy will only allow longer string repetitions. It is |
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/// useful for random data with a small character set. |
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/// </summary> |
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Filtered = 1, |
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|
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|
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/// <summary> |
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/// This strategy will not look for string repetitions at all. It |
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/// only encodes with Huffman trees (which means, that more common |
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/// characters get a smaller encoding. |
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/// </summary> |
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HuffmanOnly = 2 |
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} |
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|
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/// <summary> |
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/// Low level compression engine for deflate algorithm which uses a 32K sliding window |
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/// with secondary compression from Huffman/Shannon-Fano codes. |
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/// </summary> |
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public class DeflaterEngine : DeflaterConstants |
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{
|
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#region Constants |
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const int TooFar = 4096; |
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#endregion |
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|
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#region Constructors |
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/// <summary> |
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/// Construct instance with pending buffer |
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/// </summary> |
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/// <param name="pending"> |
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/// Pending buffer to use |
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/// </param>> |
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public DeflaterEngine(DeflaterPending pending) |
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{
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this.pending = pending; |
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huffman = new DeflaterHuffman(pending); |
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adler = new Adler32(); |
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|
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window = new byte[2 * WSIZE]; |
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head = new short[HASH_SIZE]; |
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prev = new short[WSIZE]; |
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|
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// We start at index 1, to avoid an implementation deficiency, that |
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// we cannot build a repeat pattern at index 0. |
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blockStart = strstart = 1; |
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} |
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|
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#endregion |
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|
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/// <summary> |
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/// Deflate drives actual compression of data |
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/// </summary> |
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/// <param name="flush">True to flush input buffers</param> |
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/// <param name="finish">Finish deflation with the current input.</param> |
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/// <returns>Returns true if progress has been made.</returns> |
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public bool Deflate(bool flush, bool finish) |
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{
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bool progress; |
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do |
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{
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FillWindow(); |
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var canFlush = flush && (inputOff == inputEnd); |
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switch (compressionFunction) |
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{
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case DEFLATE_STORED: |
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progress = DeflateStored(canFlush, finish); |
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break; |
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case DEFLATE_FAST: |
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progress = DeflateFast(canFlush, finish); |
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break; |
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case DEFLATE_SLOW: |
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progress = DeflateSlow(canFlush, finish); |
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break; |
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default: |
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throw new InvalidOperationException("unknown compressionFunction");
|
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} |
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} while (pending.IsFlushed && progress); // repeat while we have no pending output and progress was made |
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return progress; |
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} |
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|
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/// <summary> |
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/// Sets input data to be deflated. Should only be called when <code>NeedsInput()</code> |
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/// returns true |
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/// </summary> |
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/// <param name="buffer">The buffer containing input data.</param> |
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/// <param name="offset">The offset of the first byte of data.</param> |
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/// <param name="count">The number of bytes of data to use as input.</param> |
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public void SetInput(byte[] buffer, int offset, int count) |
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{
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if ( buffer == null ) |
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{
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throw new ArgumentNullException("buffer");
|
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} |
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|
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if ( offset < 0 ) |
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{
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throw new ArgumentOutOfRangeException("offset");
|
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} |
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|
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if ( count < 0 ) |
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{
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throw new ArgumentOutOfRangeException("count");
|
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} |
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|
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if (inputOff < inputEnd) |
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{
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throw new InvalidOperationException("Old input was not completely processed");
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} |
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|
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int end = offset + count; |
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/* We want to throw an ArrayIndexOutOfBoundsException early. The |
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* check is very tricky: it also handles integer wrap around. |
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*/ |
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if ((offset > end) || (end > buffer.Length) ) |
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{
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throw new ArgumentOutOfRangeException("count");
|
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} |
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inputBuf = buffer; |
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inputOff = offset; |
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inputEnd = end; |
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} |
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|
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/// <summary> |
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/// Determines if more <see cref="SetInput">input</see> is needed. |
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/// </summary> |
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/// <returns>Return true if input is needed via <see cref="SetInput">SetInput</see></returns> |
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public bool NeedsInput() |
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{
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return (inputEnd == inputOff); |
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} |
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|
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/// <summary> |
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/// Set compression dictionary |
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/// </summary> |
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/// <param name="buffer">The buffer containing the dictionary data</param> |
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/// <param name="offset">The offset in the buffer for the first byte of data</param> |
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/// <param name="length">The length of the dictionary data.</param> |
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public void SetDictionary(byte[] buffer, int offset, int length) |
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{
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adler.Update(buffer, offset, length); |
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if (length < MIN_MATCH) |
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{
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return; |
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} |
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|
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if (length > MAX_DIST) |
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{
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offset += length - MAX_DIST; |
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length = MAX_DIST; |
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} |
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Array.Copy(buffer, offset, window, strstart, length); |
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|
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UpdateHash(); |
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--length; |
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while (--length > 0) |
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{
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InsertString(); |
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strstart++; |
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} |
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strstart += 2; |
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blockStart = strstart; |
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} |
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|
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/// <summary> |
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/// Reset internal state |
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/// </summary> |
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public void Reset() |
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{
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huffman.Reset(); |
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adler.Reset(); |
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blockStart = strstart = 1; |
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lookahead = 0; |
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totalIn = 0; |
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prevAvailable = false; |
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matchLen = MIN_MATCH - 1; |
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|
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for (int i = 0; i < HASH_SIZE; i++) {
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head[i] = 0; |
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} |
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|
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for (int i = 0; i < WSIZE; i++) {
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prev[i] = 0; |
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} |
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} |
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|
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/// <summary> |
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/// Reset Adler checksum |
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/// </summary> |
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public void ResetAdler() |
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{
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adler.Reset(); |
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} |
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|
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/// <summary> |
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/// Get current value of Adler checksum |
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/// </summary> |
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public int Adler {
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get {
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return unchecked((int)adler.Value); |
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} |
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} |
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|
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/// <summary> |
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/// Total data processed |
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/// </summary> |
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public int TotalIn {
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get {
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return totalIn; |
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} |
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} |
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|
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/// <summary> |
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/// Get/set the <see cref="DeflateStrategy">deflate strategy</see> |
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/// </summary> |
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public DeflateStrategy Strategy {
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get {
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return strategy; |
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} |
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set {
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strategy = value; |
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} |
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} |
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|
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/// <summary> |
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/// Set the deflate level (0-9) |
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/// </summary> |
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/// <param name="level">The value to set the level to.</param> |
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public void SetLevel(int level) |
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{
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if ( (level < 0) || (level > 9) ) |
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{
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throw new ArgumentOutOfRangeException("level");
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} |
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|
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goodLength = GOOD_LENGTH[level]; |
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max_lazy = MAX_LAZY[level]; |
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niceLength = NICE_LENGTH[level]; |
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max_chain = MAX_CHAIN[level]; |
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if (COMPR_FUNC[level] == compressionFunction) |
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{
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return; |
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} |
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|
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switch (compressionFunction) {
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case DEFLATE_STORED: |
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if (strstart > blockStart) {
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huffman.FlushStoredBlock(window, blockStart, |
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strstart - blockStart, false); |
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blockStart = strstart; |
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} |
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UpdateHash(); |
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break; |
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|
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case DEFLATE_FAST: |
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if (strstart > blockStart) {
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huffman.FlushBlock(window, blockStart, strstart - blockStart, |
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false); |
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blockStart = strstart; |
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} |
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break; |
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|
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case DEFLATE_SLOW: |
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if (prevAvailable) {
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huffman.TallyLit(window[strstart-1] & 0xff); |
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} |
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if (strstart > blockStart) {
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huffman.FlushBlock(window, blockStart, strstart - blockStart, false); |
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blockStart = strstart; |
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} |
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prevAvailable = false; |
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matchLen = MIN_MATCH - 1; |
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break; |
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} |
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compressionFunction = COMPR_FUNC[level]; |
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} |
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|
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/// <summary> |
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/// Fill the window |
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/// </summary> |
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public void FillWindow() |
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{
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/* If the window is almost full and there is insufficient lookahead, |
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* move the upper half to the lower one to make room in the upper half. |
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*/ |
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if (strstart >= WSIZE + MAX_DIST) |
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{
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SlideWindow(); |
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} |
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|
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/* If there is not enough lookahead, but still some input left, |
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* read in the input |
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*/ |
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while (lookahead < MIN_LOOKAHEAD && inputOff < inputEnd) |
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{
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int more = 2 * WSIZE - lookahead - strstart; |
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|
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if (more > inputEnd - inputOff) |
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{
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more = inputEnd - inputOff; |
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} |
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|
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Array.Copy(inputBuf, inputOff, window, strstart + lookahead, more); |
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adler.Update(inputBuf, inputOff, more); |
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inputOff += more; |
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totalIn += more; |
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lookahead += more; |
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} |
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|
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if (lookahead >= MIN_MATCH) |
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{
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UpdateHash(); |
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} |
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} |
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|
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void UpdateHash() |
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{
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/* |
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if (DEBUGGING) {
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Console.WriteLine("updateHash: "+strstart);
|
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} |
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*/ |
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ins_h = (window[strstart] << HASH_SHIFT) ^ window[strstart + 1]; |
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} |
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|
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/// <summary> |
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/// Inserts the current string in the head hash and returns the previous |
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/// value for this hash. |
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/// </summary> |
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/// <returns>The previous hash value</returns> |
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int InsertString() |
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{
|
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short match; |
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var hash = ((ins_h << HASH_SHIFT) ^ window[strstart + (MIN_MATCH -1)]) & HASH_MASK; |
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prev[strstart & WMASK] = match = head[hash]; |
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head[hash] = unchecked((short)strstart); |
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ins_h = hash; |
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return match & 0xffff; |
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} |
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|
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void SlideWindow() |
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{
|
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Array.Copy(window, WSIZE, window, 0, WSIZE); |
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matchStart -= WSIZE; |
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strstart -= WSIZE; |
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blockStart -= WSIZE; |
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|
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// Slide the hash table (could be avoided with 32 bit values |
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// at the expense of memory usage). |
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for (int i = 0; i < HASH_SIZE; ++i) {
|
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int m = head[i] & 0xffff; |
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head[i] = (short)(m >= WSIZE ? (m - WSIZE) : 0); |
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} |
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|
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// Slide the prev table. |
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for (int i = 0; i < WSIZE; i++) {
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int m = prev[i] & 0xffff; |
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prev[i] = (short)(m >= WSIZE ? (m - WSIZE) : 0); |
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} |
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} |
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|
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/// <summary> |
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/// Find the best (longest) string in the window matching the |
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/// string starting at strstart. |
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/// |
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/// Preconditions: |
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/// <code> |
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/// strstart + MAX_MATCH <= window.length.</code> |
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/// </summary> |
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/// <param name="curMatch"></param> |
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/// <returns>True if a match greater than the minimum length is found</returns> |
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bool FindLongestMatch(int curMatch) |
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{
|
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var chainLength = max_chain; |
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var niceLength = this.niceLength; |
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var prev = this.prev; |
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var scan = strstart; |
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var best_end = strstart + matchLen; |
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var best_len = Math.Max(matchLen, MIN_MATCH - 1); |
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|
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int limit = Math.Max(strstart - MAX_DIST, 0); |
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|
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int strend = strstart + MAX_MATCH - 1; |
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byte scan_end1 = window[best_end - 1]; |
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byte scan_end = window[best_end]; |
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|
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// Do not waste too much time if we already have a good match: |
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if (best_len >= goodLength) {
|
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chainLength >>= 2; |
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} |
| 450 |
|
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/* Do not look for matches beyond the end of the input. This is necessary |
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* to make deflate deterministic. |
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*/ |
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if (niceLength > lookahead) {
|
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niceLength = lookahead; |
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} |
| 457 |
|
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do {
|
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if (window[curMatch + best_len] != scan_end || |
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window[curMatch + best_len - 1] != scan_end1 || |
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window[curMatch] != window[scan] || |
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window[curMatch + 1] != window[scan + 1]) {
|
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continue; |
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} |
| 465 |
|
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int match = curMatch + 2; |
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scan += 2; |
| 468 |
|
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/* We check for insufficient lookahead only every 8th comparison; |
| 470 |
* the 256th check will be made at strstart + 258. |
| 471 |
*/ |
| 472 |
while ( |
| 473 |
window[++scan] == window[++match] && |
| 474 |
window[++scan] == window[++match] && |
| 475 |
window[++scan] == window[++match] && |
| 476 |
window[++scan] == window[++match] && |
| 477 |
window[++scan] == window[++match] && |
| 478 |
window[++scan] == window[++match] && |
| 479 |
window[++scan] == window[++match] && |
| 480 |
window[++scan] == window[++match] && |
| 481 |
(scan < strend)) |
| 482 |
{
|
| 483 |
// Do nothing |
| 484 |
} |
| 485 |
|
| 486 |
if (scan > best_end) {
|
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matchStart = curMatch; |
| 488 |
best_end = scan; |
| 489 |
best_len = scan - strstart; |
| 490 |
|
| 491 |
if (best_len >= niceLength) {
|
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break; |
| 493 |
} |
| 494 |
|
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scan_end1 = window[best_end - 1]; |
| 496 |
scan_end = window[best_end]; |
| 497 |
} |
| 498 |
scan = strstart; |
| 499 |
} while ((curMatch = (prev[curMatch & WMASK] & 0xffff)) > limit && --chainLength != 0); |
| 500 |
|
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matchLen = Math.Min(best_len, lookahead); |
| 502 |
return matchLen >= MIN_MATCH; |
| 503 |
} |
| 504 |
|
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bool DeflateStored(bool flush, bool finish) |
| 506 |
{
|
| 507 |
if (!flush && (lookahead == 0)) {
|
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return false; |
| 509 |
} |
| 510 |
|
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strstart += lookahead; |
| 512 |
lookahead = 0; |
| 513 |
|
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int storedLength = strstart - blockStart; |
| 515 |
|
| 516 |
if ((storedLength >= MAX_BLOCK_SIZE) || // Block is full |
| 517 |
(blockStart < WSIZE && storedLength >= MAX_DIST) || // Block may move out of window |
| 518 |
flush) {
|
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bool lastBlock = finish; |
| 520 |
if (storedLength > MAX_BLOCK_SIZE) {
|
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storedLength = MAX_BLOCK_SIZE; |
| 522 |
lastBlock = false; |
| 523 |
} |
| 524 |
|
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huffman.FlushStoredBlock(window, blockStart, storedLength, lastBlock); |
| 526 |
blockStart += storedLength; |
| 527 |
return !lastBlock; |
| 528 |
} |
| 529 |
return true; |
| 530 |
} |
| 531 |
|
| 532 |
bool DeflateFast(bool flush, bool finish) |
| 533 |
{
|
| 534 |
if (lookahead < MIN_LOOKAHEAD && !flush) {
|
| 535 |
return false; |
| 536 |
} |
| 537 |
|
| 538 |
while (lookahead >= MIN_LOOKAHEAD || flush) {
|
| 539 |
if (lookahead == 0) {
|
| 540 |
// We are flushing everything |
| 541 |
huffman.FlushBlock(window, blockStart, strstart - blockStart, finish); |
| 542 |
blockStart = strstart; |
| 543 |
return false; |
| 544 |
} |
| 545 |
|
| 546 |
if (strstart > 2 * WSIZE - MIN_LOOKAHEAD) {
|
| 547 |
/* slide window, as FindLongestMatch needs this. |
| 548 |
* This should only happen when flushing and the window |
| 549 |
* is almost full. |
| 550 |
*/ |
| 551 |
SlideWindow(); |
| 552 |
} |
| 553 |
|
| 554 |
int hashHead; |
| 555 |
if (lookahead >= MIN_MATCH && |
| 556 |
(hashHead = InsertString()) != 0 && |
| 557 |
strategy != DeflateStrategy.HuffmanOnly && |
| 558 |
strstart - hashHead <= MAX_DIST && |
| 559 |
FindLongestMatch(hashHead)) {
|
| 560 |
// longestMatch sets matchStart and matchLen |
| 561 |
var full = huffman.TallyDist(strstart - matchStart, matchLen); |
| 562 |
|
| 563 |
lookahead -= matchLen; |
| 564 |
if (matchLen <= max_lazy && lookahead >= MIN_MATCH) {
|
| 565 |
while (--matchLen > 0) {
|
| 566 |
++strstart; |
| 567 |
InsertString(); |
| 568 |
} |
| 569 |
++strstart; |
| 570 |
} else {
|
| 571 |
strstart += matchLen; |
| 572 |
if (lookahead >= MIN_MATCH - 1) {
|
| 573 |
UpdateHash(); |
| 574 |
} |
| 575 |
} |
| 576 |
matchLen = MIN_MATCH - 1; |
| 577 |
if (!full) {
|
| 578 |
continue; |
| 579 |
} |
| 580 |
} else {
|
| 581 |
// No match found |
| 582 |
huffman.TallyLit(window[strstart] & 0xff); |
| 583 |
++strstart; |
| 584 |
--lookahead; |
| 585 |
} |
| 586 |
|
| 587 |
if (huffman.IsFull()) {
|
| 588 |
bool lastBlock = finish && (lookahead == 0); |
| 589 |
huffman.FlushBlock(window, blockStart, strstart - blockStart, lastBlock); |
| 590 |
blockStart = strstart; |
| 591 |
return !lastBlock; |
| 592 |
} |
| 593 |
} |
| 594 |
return true; |
| 595 |
} |
| 596 |
|
| 597 |
bool DeflateSlow(bool flush, bool finish) |
| 598 |
{
|
| 599 |
if (lookahead < MIN_LOOKAHEAD && !flush) {
|
| 600 |
return false; |
| 601 |
} |
| 602 |
|
| 603 |
while (lookahead >= MIN_LOOKAHEAD || flush) {
|
| 604 |
if (lookahead == 0) {
|
| 605 |
if (prevAvailable) {
|
| 606 |
huffman.TallyLit(window[strstart-1] & 0xff); |
| 607 |
} |
| 608 |
prevAvailable = false; |
| 609 |
|
| 610 |
// We are flushing everything |
| 611 |
huffman.FlushBlock(window, blockStart, strstart - blockStart, |
| 612 |
finish); |
| 613 |
blockStart = strstart; |
| 614 |
return false; |
| 615 |
} |
| 616 |
|
| 617 |
if (strstart >= 2 * WSIZE - MIN_LOOKAHEAD) {
|
| 618 |
/* slide window, as FindLongestMatch needs this. |
| 619 |
* This should only happen when flushing and the window |
| 620 |
* is almost full. |
| 621 |
*/ |
| 622 |
SlideWindow(); |
| 623 |
} |
| 624 |
|
| 625 |
int prevMatch = matchStart; |
| 626 |
int prevLen = matchLen; |
| 627 |
if (lookahead >= MIN_MATCH) {
|
| 628 |
|
| 629 |
int hashHead = InsertString(); |
| 630 |
|
| 631 |
if (strategy != DeflateStrategy.HuffmanOnly && |
| 632 |
hashHead != 0 && |
| 633 |
strstart - hashHead <= MAX_DIST && |
| 634 |
FindLongestMatch(hashHead)) {
|
| 635 |
|
| 636 |
// longestMatch sets matchStart and matchLen |
| 637 |
|
| 638 |
// Discard match if too small and too far away |
| 639 |
if (matchLen <= 5 && (strategy == DeflateStrategy.Filtered || (matchLen == MIN_MATCH && strstart - matchStart > TooFar))) {
|
| 640 |
matchLen = MIN_MATCH - 1; |
| 641 |
} |
| 642 |
} |
| 643 |
} |
| 644 |
|
| 645 |
// previous match was better |
| 646 |
if ((prevLen >= MIN_MATCH) && (matchLen <= prevLen) ) {
|
| 647 |
huffman.TallyDist(strstart - 1 - prevMatch, prevLen); |
| 648 |
prevLen -= 2; |
| 649 |
do {
|
| 650 |
strstart++; |
| 651 |
lookahead--; |
| 652 |
if (lookahead >= MIN_MATCH) {
|
| 653 |
InsertString(); |
| 654 |
} |
| 655 |
} while (--prevLen > 0); |
| 656 |
|
| 657 |
strstart ++; |
| 658 |
lookahead--; |
| 659 |
prevAvailable = false; |
| 660 |
matchLen = MIN_MATCH - 1; |
| 661 |
} else {
|
| 662 |
if (prevAvailable) {
|
| 663 |
huffman.TallyLit(window[strstart-1] & 0xff); |
| 664 |
} |
| 665 |
prevAvailable = true; |
| 666 |
strstart++; |
| 667 |
lookahead--; |
| 668 |
} |
| 669 |
|
| 670 |
if (huffman.IsFull()) {
|
| 671 |
int len = strstart - blockStart; |
| 672 |
if (prevAvailable) {
|
| 673 |
len--; |
| 674 |
} |
| 675 |
bool lastBlock = (finish && (lookahead == 0) && !prevAvailable); |
| 676 |
huffman.FlushBlock(window, blockStart, len, lastBlock); |
| 677 |
blockStart += len; |
| 678 |
return !lastBlock; |
| 679 |
} |
| 680 |
} |
| 681 |
return true; |
| 682 |
} |
| 683 |
|
| 684 |
#region Instance Fields |
| 685 |
|
| 686 |
// Hash index of string to be inserted |
| 687 |
int ins_h; |
| 688 |
|
| 689 |
/// <summary> |
| 690 |
/// Hashtable, hashing three characters to an index for window, so |
| 691 |
/// that window[index]..window[index+2] have this hash code. |
| 692 |
/// Note that the array should really be unsigned short, so you need |
| 693 |
/// to and the values with 0xffff. |
| 694 |
/// </summary> |
| 695 |
readonly short[] head; |
| 696 |
|
| 697 |
/// <summary> |
| 698 |
/// <code>prev[index & WMASK]</code> points to the previous index that has the |
| 699 |
/// same hash code as the string starting at index. This way |
| 700 |
/// entries with the same hash code are in a linked list. |
| 701 |
/// Note that the array should really be unsigned short, so you need |
| 702 |
/// to and the values with 0xffff. |
| 703 |
/// </summary> |
| 704 |
readonly short[] prev; |
| 705 |
|
| 706 |
int matchStart; |
| 707 |
// Length of best match |
| 708 |
int matchLen; |
| 709 |
// Set if previous match exists |
| 710 |
bool prevAvailable; |
| 711 |
int blockStart; |
| 712 |
|
| 713 |
/// <summary> |
| 714 |
/// Points to the current character in the window. |
| 715 |
/// </summary> |
| 716 |
int strstart; |
| 717 |
|
| 718 |
/// <summary> |
| 719 |
/// lookahead is the number of characters starting at strstart in |
| 720 |
/// window that are valid. |
| 721 |
/// So window[strstart] until window[strstart+lookahead-1] are valid |
| 722 |
/// characters. |
| 723 |
/// </summary> |
| 724 |
int lookahead; |
| 725 |
|
| 726 |
/// <summary> |
| 727 |
/// This array contains the part of the uncompressed stream that |
| 728 |
/// is of relevance. The current character is indexed by strstart. |
| 729 |
/// </summary> |
| 730 |
readonly byte[] window; |
| 731 |
|
| 732 |
DeflateStrategy strategy; |
| 733 |
int max_chain, max_lazy, niceLength, goodLength; |
| 734 |
|
| 735 |
/// <summary> |
| 736 |
/// The current compression function. |
| 737 |
/// </summary> |
| 738 |
int compressionFunction; |
| 739 |
|
| 740 |
/// <summary> |
| 741 |
/// The input data for compression. |
| 742 |
/// </summary> |
| 743 |
byte[] inputBuf; |
| 744 |
|
| 745 |
/// <summary> |
| 746 |
/// The total bytes of input read. |
| 747 |
/// </summary> |
| 748 |
int totalIn; |
| 749 |
|
| 750 |
/// <summary> |
| 751 |
/// The offset into inputBuf, where input data starts. |
| 752 |
/// </summary> |
| 753 |
int inputOff; |
| 754 |
|
| 755 |
/// <summary> |
| 756 |
/// The end offset of the input data. |
| 757 |
/// </summary> |
| 758 |
int inputEnd; |
| 759 |
|
| 760 |
readonly DeflaterPending pending; |
| 761 |
readonly DeflaterHuffman huffman; |
| 762 |
|
| 763 |
/// <summary> |
| 764 |
/// The adler checksum |
| 765 |
/// </summary> |
| 766 |
readonly Adler32 adler; |
| 767 |
#endregion |
| 768 |
} |
| 769 |
} |