653 lines
27 KiB
C#
653 lines
27 KiB
C#
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// ==++==
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//
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// Copyright (c) Microsoft Corporation. All rights reserved.
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//
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// zlib.h -- interface of the 'zlib' general purpose compression library
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// version 1.2.1, November 17th, 2003
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//
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// Copyright (C) 1995-2003 Jean-loup Gailly and Mark Adler
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//
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// This software is provided 'as-is', without any express or implied
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// warranty. In no event will the authors be held liable for any damages
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// arising from the use of this software.
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//
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// Permission is granted to anyone to use this software for any purpose,
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// including commercial applications, and to alter it and redistribute it
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// freely, subject to the following restrictions:
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//
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// 1. The origin of this software must not be misrepresented; you must not
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// claim that you wrote the original software. If you use this software
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// in a product, an acknowledgment in the product documentation would be
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// appreciated but is not required.
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// 2. Altered source versions must be plainly marked as such, and must not be
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// misrepresented as being the original software.
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// 3. This notice may not be removed or altered from any source distribution.
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//
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//
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// ==--==
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namespace System.IO.Compression
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{
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using System;
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using System.Diagnostics;
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internal class Inflater {
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// const tables used in decoding:
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// Extra bits for length code 257 - 285.
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private static readonly byte[] extraLengthBits = {
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0,0,0,0,0,0,0,0,1,1,1,1,2,2,2,2,3,3,3,3,4,4,4,4,5,5,5,5,0};
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// The base length for length code 257 - 285.
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// The formula to get the real length for a length code is lengthBase[code - 257] + (value stored in extraBits)
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private static readonly int[] lengthBase = {
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3,4,5,6,7,8,9,10,11,13,15,17,19,23,27,31,35,43,51,59,67,83,99,115,131,163,195,227,258};
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// The base distance for distance code 0 - 29
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// The real distance for a distance code is distanceBasePosition[code] + (value stored in extraBits)
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private static readonly int[] distanceBasePosition= {
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1,2,3,4,5,7,9,13,17,25,33,49,65,97,129,193,257,385,513,769,1025,1537,2049,3073,4097,6145,8193,12289,16385,24577,0,0};
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// code lengths for code length alphabet is stored in following order
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private static readonly byte[] codeOrder = {16,17,18,0,8,7,9,6,10,5,11,4,12,3,13,2,14,1,15};
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private static readonly byte[] staticDistanceTreeTable = {
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0x00,0x10,0x08,0x18,0x04,0x14,0x0c,0x1c,0x02,0x12,0x0a,0x1a,
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0x06,0x16,0x0e,0x1e,0x01,0x11,0x09,0x19,0x05,0x15,0x0d,0x1d,
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0x03,0x13,0x0b,0x1b,0x07,0x17,0x0f,0x1f,
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};
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private OutputWindow output;
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private InputBuffer input;
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HuffmanTree literalLengthTree;
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HuffmanTree distanceTree;
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InflaterState state;
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bool hasFormatReader;
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int bfinal;
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BlockType blockType;
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// uncompressed block
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byte[] blockLengthBuffer = new byte[4];
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int blockLength;
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// compressed block
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private int length;
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private int distanceCode;
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private int extraBits;
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private int loopCounter;
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private int literalLengthCodeCount;
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private int distanceCodeCount;
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private int codeLengthCodeCount;
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private int codeArraySize;
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private int lengthCode;
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private byte[] codeList; // temporary array to store the code length for literal/Length and distance
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private byte[] codeLengthTreeCodeLength;
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HuffmanTree codeLengthTree;
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IFileFormatReader formatReader; // class to decode header and footer (e.g. gzip)
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public Inflater() {
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output = new OutputWindow();
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input = new InputBuffer();
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codeList = new byte[HuffmanTree.MaxLiteralTreeElements + HuffmanTree.MaxDistTreeElements];
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codeLengthTreeCodeLength = new byte[HuffmanTree.NumberOfCodeLengthTreeElements];
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Reset();
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}
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internal void SetFileFormatReader(IFileFormatReader reader) {
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formatReader = reader;
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hasFormatReader = true;
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Reset();
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}
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private void Reset() {
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if ( hasFormatReader) {
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state = InflaterState.ReadingHeader; // start by reading Header info
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}
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else {
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state = InflaterState.ReadingBFinal; // start by reading BFinal bit
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}
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}
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public void SetInput(byte[] inputBytes, int offset, int length) {
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input.SetInput(inputBytes, offset, length); // append the bytes
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}
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public bool Finished() {
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return (state == InflaterState.Done || state== InflaterState.VerifyingFooter);
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}
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public int AvailableOutput{
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get {
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return output.AvailableBytes;
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}
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}
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public bool NeedsInput(){
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return input.NeedsInput();
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}
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public int Inflate(byte[] bytes, int offset, int length) {
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// copy bytes from output to outputbytes if we have aviable bytes
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// if buffer is not filled up. keep decoding until no input are available
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// if decodeBlock returns false. Throw an exception.
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int count = 0;
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do
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{
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int copied = output.CopyTo(bytes, offset, length);
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if( copied > 0) {
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if( hasFormatReader) {
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formatReader.UpdateWithBytesRead(bytes, offset, copied);
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}
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offset += copied;
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count += copied;
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length -= copied;
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}
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if (length == 0) { // filled in the bytes array
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break;
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}
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// Decode will return false when more input is needed
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} while ( !Finished() && Decode());
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if( state == InflaterState.VerifyingFooter) { // finished reading CRC
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// In this case finished is true and output window has all the data.
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// But some data in output window might not be copied out.
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if( output.AvailableBytes == 0) {
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formatReader.Validate();
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}
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}
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return count;
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}
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//Each block of compressed data begins with 3 header bits
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// containing the following data:
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// first bit BFINAL
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// next 2 bits BTYPE
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// Note that the header bits do not necessarily begin on a byte
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// boundary, since a block does not necessarily occupy an integral
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// number of bytes.
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// BFINAL is set if and only if this is the last block of the data
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// set.
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// BTYPE specifies how the data are compressed, as follows:
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// 00 - no compression
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// 01 - compressed with fixed Huffman codes
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// 10 - compressed with dynamic Huffman codes
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// 11 - reserved (error)
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// The only difference between the two compressed cases is how the
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// Huffman codes for the literal/length and distance alphabets are
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// defined.
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//
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// This function returns true for success (end of block or output window is full,)
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// false if we are short of input
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//
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private bool Decode() {
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bool eob = false;
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bool result = false;
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if( Finished()) {
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return true;
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}
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if (hasFormatReader) {
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if (state == InflaterState.ReadingHeader) {
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if (!formatReader.ReadHeader(input)) {
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return false;
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}
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state = InflaterState.ReadingBFinal;
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}
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else if (state == InflaterState.StartReadingFooter || state == InflaterState.ReadingFooter) {
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if (!formatReader.ReadFooter(input))
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return false;
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state = InflaterState.VerifyingFooter;
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return true;
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}
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}
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if( state == InflaterState.ReadingBFinal) { // reading bfinal bit
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// Need 1 bit
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if (!input.EnsureBitsAvailable(1))
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return false;
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bfinal = input.GetBits(1);
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state = InflaterState.ReadingBType;
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}
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if( state == InflaterState.ReadingBType) {
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// Need 2 bits
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if (!input.EnsureBitsAvailable(2)) {
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state = InflaterState.ReadingBType;
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return false;
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}
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blockType = (BlockType)input.GetBits(2);
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if (blockType == BlockType.Dynamic) {
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Debug.WriteLineIf(CompressionTracingSwitch.Informational, "Decoding Dynamic Block", "Compression");
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state = InflaterState.ReadingNumLitCodes;
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}
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else if (blockType == BlockType.Static) {
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Debug.WriteLineIf(CompressionTracingSwitch.Informational, "Decoding Static Block", "Compression");
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literalLengthTree = HuffmanTree.StaticLiteralLengthTree;
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distanceTree = HuffmanTree.StaticDistanceTree;
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state = InflaterState.DecodeTop;
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}
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else if (blockType == BlockType.Uncompressed) {
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Debug.WriteLineIf(CompressionTracingSwitch.Informational, "Decoding UnCompressed Block", "Compression");
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state = InflaterState.UncompressedAligning;
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}
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else {
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throw new InvalidDataException(SR.GetString(SR.UnknownBlockType));
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}
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}
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if (blockType == BlockType.Dynamic) {
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if (state < InflaterState.DecodeTop) { // we are reading the header
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result = DecodeDynamicBlockHeader();
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}
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else {
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result = DecodeBlock(out eob); // this can returns true when output is full
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}
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}
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else if (blockType == BlockType.Static) {
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result = DecodeBlock(out eob);
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}
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else if (blockType == BlockType.Uncompressed) {
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result = DecodeUncompressedBlock(out eob);
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}
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else {
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throw new InvalidDataException(SR.GetString(SR.UnknownBlockType));
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}
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//
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// If we reached the end of the block and the block we were decoding had
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// bfinal=1 (final block)
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//
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if (eob && (bfinal != 0)) {
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if (hasFormatReader)
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state = InflaterState.StartReadingFooter;
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else
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state = InflaterState.Done;
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}
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return result;
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}
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// Format of Non-compressed blocks (BTYPE=00):
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//
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// Any bits of input up to the next byte boundary are ignored.
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// The rest of the block consists of the following information:
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//
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// 0 1 2 3 4...
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// +---+---+---+---+================================+
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// | LEN | NLEN |... LEN bytes of literal data...|
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// +---+---+---+---+================================+
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//
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// LEN is the number of data bytes in the block. NLEN is the
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// one's complement of LEN.
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bool DecodeUncompressedBlock(out bool end_of_block) {
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end_of_block = false;
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while(true) {
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switch( state) {
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case InflaterState.UncompressedAligning: // intial state when calling this function
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// we must skip to a byte boundary
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input.SkipToByteBoundary();
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state = InflaterState.UncompressedByte1;
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goto case InflaterState.UncompressedByte1;
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case InflaterState.UncompressedByte1: // decoding block length
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case InflaterState.UncompressedByte2:
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case InflaterState.UncompressedByte3:
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case InflaterState.UncompressedByte4:
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int bits = input.GetBits(8);
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if( bits < 0) {
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return false;
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}
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blockLengthBuffer[state - InflaterState.UncompressedByte1] = (byte)bits;
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if( state == InflaterState.UncompressedByte4) {
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blockLength = blockLengthBuffer[0] + ((int)blockLengthBuffer[1]) * 256;
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int blockLengthComplement= blockLengthBuffer[2] + ((int)blockLengthBuffer[3]) * 256;
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// make sure complement matches
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if ((ushort) blockLength != (ushort)(~blockLengthComplement)) {
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throw new InvalidDataException(SR.GetString(SR.InvalidBlockLength));
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}
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}
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state += 1;
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break;
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case InflaterState.DecodingUncompressed: // copying block data
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// Directly copy bytes from input to output.
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int bytesCopied = output.CopyFrom(input, blockLength);
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blockLength -= bytesCopied;
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if (blockLength == 0) {
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// Done with this block, need to re-init bit buffer for next block
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state = InflaterState.ReadingBFinal;
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end_of_block = true;
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Debug.WriteLineIf(CompressionTracingSwitch.Informational, "End of Block", "Compression");
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return true;
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}
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// We can fail to copy all bytes for two reasons:
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// Running out of Input
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// running out of free space in output window
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if(output.FreeBytes == 0) {
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return true;
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}
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return false;
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default:
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Debug.Assert(false, "check why we are here!");
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throw new InvalidDataException(SR.GetString(SR.UnknownState));
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}
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}
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}
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bool DecodeBlock(out bool end_of_block_code_seen) {
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end_of_block_code_seen = false;
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int freeBytes = output.FreeBytes; // it is a little bit faster than frequently accessing the property
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while(freeBytes > 258) {
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// 258 means we can safely do decoding since maximum repeat length is 258
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int symbol;
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switch (state) {
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case InflaterState.DecodeTop:
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// decode an element from the literal tree
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//
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symbol = literalLengthTree.GetNextSymbol(input);
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if( symbol < 0) { // running out of input
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return false;
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}
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|
if (symbol < 256) { // literal
|
||
|
|
output.Write((byte)symbol);
|
||
|
|
--freeBytes;
|
||
|
|
}
|
||
|
|
else if( symbol == 256) { // end of block
|
||
|
|
end_of_block_code_seen = true;
|
||
|
|
Debug.WriteLineIf(CompressionTracingSwitch.Informational, "End of Block", "Compression");
|
||
|
|
// Reset state
|
||
|
|
state = InflaterState.ReadingBFinal;
|
||
|
|
return true; // ***********
|
||
|
|
}
|
||
|
|
else { // length/distance pair
|
||
|
|
symbol -= 257; // length code started at 257
|
||
|
|
if( symbol < 8) {
|
||
|
|
symbol += 3; // match length = 3,4,5,6,7,8,9,10
|
||
|
|
extraBits = 0;
|
||
|
|
}
|
||
|
|
else if( symbol == 28) { // extra bits for code 285 is 0
|
||
|
|
symbol = 258; // code 285 means length 258
|
||
|
|
extraBits = 0;
|
||
|
|
}
|
||
|
|
else {
|
||
|
|
if( symbol < 0 || symbol >= extraLengthBits.Length ) {
|
||
|
|
throw new InvalidDataException(SR.GetString(SR.GenericInvalidData));
|
||
|
|
}
|
||
|
|
extraBits = extraLengthBits[symbol];
|
||
|
|
Debug.Assert(extraBits != 0, "We handle other cases seperately!");
|
||
|
|
}
|
||
|
|
length = symbol;
|
||
|
|
goto case InflaterState.HaveInitialLength;
|
||
|
|
}
|
||
|
|
break;
|
||
|
|
|
||
|
|
case InflaterState.HaveInitialLength:
|
||
|
|
if( extraBits > 0) {
|
||
|
|
state = InflaterState.HaveInitialLength;
|
||
|
|
int bits = input.GetBits(extraBits);
|
||
|
|
if( bits < 0) {
|
||
|
|
return false;
|
||
|
|
}
|
||
|
|
|
||
|
|
if( length < 0 || length >= lengthBase.Length ) {
|
||
|
|
throw new InvalidDataException(SR.GetString(SR.GenericInvalidData));
|
||
|
|
}
|
||
|
|
length = lengthBase[length] + bits;
|
||
|
|
}
|
||
|
|
state = InflaterState.HaveFullLength;
|
||
|
|
goto case InflaterState.HaveFullLength;
|
||
|
|
|
||
|
|
case InflaterState.HaveFullLength:
|
||
|
|
if( blockType == BlockType.Dynamic) {
|
||
|
|
distanceCode = distanceTree.GetNextSymbol(input);
|
||
|
|
}
|
||
|
|
else { // get distance code directly for static block
|
||
|
|
distanceCode = input.GetBits(5);
|
||
|
|
if( distanceCode >= 0 ) {
|
||
|
|
distanceCode = staticDistanceTreeTable[distanceCode];
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
if( distanceCode < 0) { // running out input
|
||
|
|
return false;
|
||
|
|
}
|
||
|
|
|
||
|
|
state = InflaterState.HaveDistCode;
|
||
|
|
goto case InflaterState.HaveDistCode;
|
||
|
|
|
||
|
|
case InflaterState.HaveDistCode:
|
||
|
|
// To avoid a table lookup we note that for distanceCode >= 2,
|
||
|
|
// extra_bits = (distanceCode-2) >> 1
|
||
|
|
int offset;
|
||
|
|
if( distanceCode > 3) {
|
||
|
|
extraBits = (distanceCode-2) >> 1;
|
||
|
|
int bits = input.GetBits(extraBits);
|
||
|
|
if( bits < 0 ) {
|
||
|
|
return false;
|
||
|
|
}
|
||
|
|
offset = distanceBasePosition[distanceCode] + bits;
|
||
|
|
}
|
||
|
|
else {
|
||
|
|
offset = distanceCode + 1;
|
||
|
|
}
|
||
|
|
|
||
|
|
Debug.Assert(freeBytes>= 258, "following operation is not safe!");
|
||
|
|
output.WriteLengthDistance(length, offset);
|
||
|
|
freeBytes -= length;
|
||
|
|
state = InflaterState.DecodeTop;
|
||
|
|
break;
|
||
|
|
|
||
|
|
default:
|
||
|
|
Debug.Assert(false, "check why we are here!");
|
||
|
|
throw new InvalidDataException(SR.GetString(SR.UnknownState));
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
return true;
|
||
|
|
}
|
||
|
|
|
||
|
|
|
||
|
|
// Format of the dynamic block header:
|
||
|
|
// 5 Bits: HLIT, # of Literal/Length codes - 257 (257 - 286)
|
||
|
|
// 5 Bits: HDIST, # of Distance codes - 1 (1 - 32)
|
||
|
|
// 4 Bits: HCLEN, # of Code Length codes - 4 (4 - 19)
|
||
|
|
//
|
||
|
|
// (HCLEN + 4) x 3 bits: code lengths for the code length
|
||
|
|
// alphabet given just above, in the order: 16, 17, 18,
|
||
|
|
// 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15
|
||
|
|
//
|
||
|
|
// These code lengths are interpreted as 3-bit integers
|
||
|
|
// (0-7); as above, a code length of 0 means the
|
||
|
|
// corresponding symbol (literal/length or distance code
|
||
|
|
// length) is not used.
|
||
|
|
//
|
||
|
|
// HLIT + 257 code lengths for the literal/length alphabet,
|
||
|
|
// encoded using the code length Huffman code
|
||
|
|
//
|
||
|
|
// HDIST + 1 code lengths for the distance alphabet,
|
||
|
|
// encoded using the code length Huffman code
|
||
|
|
//
|
||
|
|
// The code length repeat codes can cross from HLIT + 257 to the
|
||
|
|
// HDIST + 1 code lengths. In other words, all code lengths form
|
||
|
|
// a single sequence of HLIT + HDIST + 258 values.
|
||
|
|
bool DecodeDynamicBlockHeader() {
|
||
|
|
switch (state) {
|
||
|
|
case InflaterState.ReadingNumLitCodes:
|
||
|
|
literalLengthCodeCount = input.GetBits(5);
|
||
|
|
if( literalLengthCodeCount < 0) {
|
||
|
|
return false;
|
||
|
|
}
|
||
|
|
literalLengthCodeCount += 257;
|
||
|
|
state = InflaterState.ReadingNumDistCodes;
|
||
|
|
goto case InflaterState.ReadingNumDistCodes;
|
||
|
|
|
||
|
|
case InflaterState.ReadingNumDistCodes:
|
||
|
|
distanceCodeCount = input.GetBits(5);
|
||
|
|
if( distanceCodeCount < 0) {
|
||
|
|
return false;
|
||
|
|
}
|
||
|
|
distanceCodeCount += 1;
|
||
|
|
state = InflaterState.ReadingNumCodeLengthCodes;
|
||
|
|
goto case InflaterState.ReadingNumCodeLengthCodes;
|
||
|
|
|
||
|
|
case InflaterState.ReadingNumCodeLengthCodes:
|
||
|
|
codeLengthCodeCount = input.GetBits(4);
|
||
|
|
if( codeLengthCodeCount < 0) {
|
||
|
|
return false;
|
||
|
|
}
|
||
|
|
codeLengthCodeCount += 4;
|
||
|
|
loopCounter = 0;
|
||
|
|
state = InflaterState.ReadingCodeLengthCodes;
|
||
|
|
goto case InflaterState.ReadingCodeLengthCodes;
|
||
|
|
|
||
|
|
case InflaterState.ReadingCodeLengthCodes:
|
||
|
|
while(loopCounter < codeLengthCodeCount) {
|
||
|
|
int bits = input.GetBits(3);
|
||
|
|
if( bits < 0) {
|
||
|
|
return false;
|
||
|
|
}
|
||
|
|
codeLengthTreeCodeLength[codeOrder[loopCounter]] = (byte)bits;
|
||
|
|
++loopCounter;
|
||
|
|
}
|
||
|
|
|
||
|
|
for (int i = codeLengthCodeCount; i < codeOrder.Length; i++) {
|
||
|
|
codeLengthTreeCodeLength[ codeOrder[i] ] = 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
// create huffman tree for code length
|
||
|
|
codeLengthTree = new HuffmanTree(codeLengthTreeCodeLength);
|
||
|
|
codeArraySize = literalLengthCodeCount + distanceCodeCount;
|
||
|
|
loopCounter = 0; // reset loop count
|
||
|
|
|
||
|
|
state = InflaterState.ReadingTreeCodesBefore;
|
||
|
|
goto case InflaterState.ReadingTreeCodesBefore;
|
||
|
|
|
||
|
|
case InflaterState.ReadingTreeCodesBefore:
|
||
|
|
case InflaterState.ReadingTreeCodesAfter:
|
||
|
|
while (loopCounter < codeArraySize) {
|
||
|
|
if( state == InflaterState.ReadingTreeCodesBefore) {
|
||
|
|
if( (lengthCode = codeLengthTree.GetNextSymbol(input)) < 0) {
|
||
|
|
return false;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
// The alphabet for code lengths is as follows:
|
||
|
|
// 0 - 15: Represent code lengths of 0 - 15
|
||
|
|
// 16: Copy the previous code length 3 - 6 times.
|
||
|
|
// The next 2 bits indicate repeat length
|
||
|
|
// (0 = 3, ... , 3 = 6)
|
||
|
|
// Example: Codes 8, 16 (+2 bits 11),
|
||
|
|
// 16 (+2 bits 10) will expand to
|
||
|
|
// 12 code lengths of 8 (1 + 6 + 5)
|
||
|
|
// 17: Repeat a code length of 0 for 3 - 10 times.
|
||
|
|
// (3 bits of length)
|
||
|
|
// 18: Repeat a code length of 0 for 11 - 138 times
|
||
|
|
// (7 bits of length)
|
||
|
|
if (lengthCode <= 15) {
|
||
|
|
codeList[loopCounter++] = (byte)lengthCode;
|
||
|
|
}
|
||
|
|
else {
|
||
|
|
if( !input.EnsureBitsAvailable(7)) { // it doesn't matter if we require more bits here
|
||
|
|
state = InflaterState.ReadingTreeCodesAfter;
|
||
|
|
return false;
|
||
|
|
}
|
||
|
|
|
||
|
|
int repeatCount;
|
||
|
|
if (lengthCode == 16) {
|
||
|
|
if (loopCounter == 0) { // can't have "prev code" on first code
|
||
|
|
throw new InvalidDataException();
|
||
|
|
}
|
||
|
|
|
||
|
|
byte previousCode = codeList[loopCounter-1];
|
||
|
|
repeatCount = input.GetBits(2) + 3;
|
||
|
|
|
||
|
|
if (loopCounter + repeatCount > codeArraySize) {
|
||
|
|
throw new InvalidDataException();
|
||
|
|
}
|
||
|
|
|
||
|
|
for (int j = 0; j < repeatCount; j++) {
|
||
|
|
codeList[loopCounter++] = previousCode;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
else if (lengthCode == 17) {
|
||
|
|
repeatCount = input.GetBits(3) + 3;
|
||
|
|
|
||
|
|
if (loopCounter + repeatCount > codeArraySize) {
|
||
|
|
throw new InvalidDataException();
|
||
|
|
}
|
||
|
|
|
||
|
|
for (int j = 0; j < repeatCount; j++) {
|
||
|
|
codeList[loopCounter++] = 0;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
else { // code == 18
|
||
|
|
repeatCount = input.GetBits(7) + 11;
|
||
|
|
|
||
|
|
if (loopCounter + repeatCount > codeArraySize) {
|
||
|
|
throw new InvalidDataException();
|
||
|
|
}
|
||
|
|
|
||
|
|
for (int j = 0; j < repeatCount; j++) {
|
||
|
|
codeList[loopCounter++] = 0;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
state = InflaterState.ReadingTreeCodesBefore; // we want to read the next code.
|
||
|
|
}
|
||
|
|
break;
|
||
|
|
|
||
|
|
default:
|
||
|
|
Debug.Assert(false, "check why we are here!");
|
||
|
|
throw new InvalidDataException(SR.GetString(SR.UnknownState));
|
||
|
|
}
|
||
|
|
|
||
|
|
byte[] literalTreeCodeLength = new byte[HuffmanTree.MaxLiteralTreeElements];
|
||
|
|
byte[] distanceTreeCodeLength = new byte[HuffmanTree.MaxDistTreeElements];
|
||
|
|
|
||
|
|
// Create literal and distance tables
|
||
|
|
Array.Copy(codeList, literalTreeCodeLength, literalLengthCodeCount);
|
||
|
|
Array.Copy(codeList, literalLengthCodeCount, distanceTreeCodeLength, 0, distanceCodeCount);
|
||
|
|
|
||
|
|
// Make sure there is an end-of-block code, otherwise how could we ever end?
|
||
|
|
if (literalTreeCodeLength[HuffmanTree.EndOfBlockCode] == 0) {
|
||
|
|
throw new InvalidDataException();
|
||
|
|
}
|
||
|
|
|
||
|
|
literalLengthTree = new HuffmanTree(literalTreeCodeLength);
|
||
|
|
distanceTree = new HuffmanTree(distanceTreeCodeLength);
|
||
|
|
state = InflaterState.DecodeTop;
|
||
|
|
return true;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
|