kopia lustrzana https://github.com/dl2alf/AirScout
1796 wiersze
71 KiB
C#
1796 wiersze
71 KiB
C#
// Inflate.cs
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// ------------------------------------------------------------------
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//
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// Copyright (c) 2009 Dino Chiesa and Microsoft Corporation.
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// All rights reserved.
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//
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// This code module is part of DotNetZip, a zipfile class library.
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//
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// ------------------------------------------------------------------
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//
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// This code is licensed under the Microsoft Public License.
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// See the file License.txt for the license details.
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// More info on: http://dotnetzip.codeplex.com
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//
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// ------------------------------------------------------------------
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//
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// last saved (in emacs):
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// Time-stamp: <2010-January-08 18:32:12>
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//
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// ------------------------------------------------------------------
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//
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// This module defines classes for decompression. This code is derived
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// from the jzlib implementation of zlib, but significantly modified.
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// The object model is not the same, and many of the behaviors are
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// different. Nonetheless, in keeping with the license for jzlib, I am
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// reproducing the copyright to that code here.
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//
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// ------------------------------------------------------------------
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//
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// Copyright (c) 2000,2001,2002,2003 ymnk, JCraft,Inc. All rights reserved.
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//
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// Redistribution and use in source and binary forms, with or without
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// modification, are permitted provided that the following conditions are met:
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//
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// 1. Redistributions of source code must retain the above copyright notice,
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// this list of conditions and the following disclaimer.
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//
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// 2. Redistributions in binary form must reproduce the above copyright
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// notice, this list of conditions and the following disclaimer in
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// the documentation and/or other materials provided with the distribution.
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//
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// 3. The names of the authors may not be used to endorse or promote products
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// derived from this software without specific prior written permission.
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//
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// THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES,
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// INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
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// FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL JCRAFT,
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// INC. OR ANY CONTRIBUTORS TO THIS SOFTWARE BE LIABLE FOR ANY DIRECT, INDIRECT,
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// INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
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// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA,
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// OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
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// LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
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// NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
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// EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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//
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// -----------------------------------------------------------------------
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//
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// This program is based on zlib-1.1.3; credit to authors
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// Jean-loup Gailly(jloup@gzip.org) and Mark Adler(madler@alumni.caltech.edu)
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// and contributors of zlib.
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//
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// -----------------------------------------------------------------------
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using System;
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namespace Ionic.Zlib
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{
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sealed class InflateBlocks
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{
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private const int MANY = 1440;
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// Table for deflate from PKZIP's appnote.txt.
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internal static readonly int[] border = new int[]
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{ 16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15 };
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private enum InflateBlockMode
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{
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TYPE = 0, // get type bits (3, including end bit)
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LENS = 1, // get lengths for stored
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STORED = 2, // processing stored block
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TABLE = 3, // get table lengths
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BTREE = 4, // get bit lengths tree for a dynamic block
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DTREE = 5, // get length, distance trees for a dynamic block
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CODES = 6, // processing fixed or dynamic block
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DRY = 7, // output remaining window bytes
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DONE = 8, // finished last block, done
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BAD = 9, // ot a data error--stuck here
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}
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private InflateBlockMode mode; // current inflate_block mode
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internal int left; // if STORED, bytes left to copy
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internal int table; // table lengths (14 bits)
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internal int index; // index into blens (or border)
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internal int[] blens; // bit lengths of codes
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internal int[] bb = new int[1]; // bit length tree depth
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internal int[] tb = new int[1]; // bit length decoding tree
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internal InflateCodes codes = new InflateCodes(); // if CODES, current state
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internal int last; // true if this block is the last block
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internal ZlibCodec _codec; // pointer back to this zlib stream
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// mode independent information
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internal int bitk; // bits in bit buffer
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internal int bitb; // bit buffer
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internal int[] hufts; // single malloc for tree space
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internal byte[] window; // sliding window
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internal int end; // one byte after sliding window
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internal int readAt; // window read pointer
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internal int writeAt; // window write pointer
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internal System.Object checkfn; // check function
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internal uint check; // check on output
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internal InfTree inftree = new InfTree();
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internal InflateBlocks(ZlibCodec codec, System.Object checkfn, int w)
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{
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_codec = codec;
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hufts = new int[MANY * 3];
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window = new byte[w];
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end = w;
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this.checkfn = checkfn;
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mode = InflateBlockMode.TYPE;
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Reset();
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}
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internal uint Reset()
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{
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uint oldCheck = check;
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mode = InflateBlockMode.TYPE;
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bitk = 0;
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bitb = 0;
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readAt = writeAt = 0;
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if (checkfn != null)
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_codec._Adler32 = check = Adler.Adler32(0, null, 0, 0);
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return oldCheck;
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}
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internal int Process(int r)
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{
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int t; // temporary storage
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int b; // bit buffer
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int k; // bits in bit buffer
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int p; // input data pointer
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int n; // bytes available there
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int q; // output window write pointer
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int m; // bytes to end of window or read pointer
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// copy input/output information to locals (UPDATE macro restores)
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p = _codec.NextIn;
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n = _codec.AvailableBytesIn;
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b = bitb;
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k = bitk;
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q = writeAt;
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m = (int)(q < readAt ? readAt - q - 1 : end - q);
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// process input based on current state
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while (true)
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{
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switch (mode)
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{
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case InflateBlockMode.TYPE:
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while (k < (3))
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{
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if (n != 0)
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{
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r = ZlibConstants.Z_OK;
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}
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else
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{
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bitb = b; bitk = k;
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_codec.AvailableBytesIn = n;
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_codec.TotalBytesIn += p - _codec.NextIn;
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_codec.NextIn = p;
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writeAt = q;
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return Flush(r);
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}
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n--;
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b |= (_codec.InputBuffer[p++] & 0xff) << k;
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k += 8;
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}
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t = (int)(b & 7);
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last = t & 1;
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switch ((uint)t >> 1)
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{
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case 0: // stored
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b >>= 3; k -= (3);
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t = k & 7; // go to byte boundary
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b >>= t; k -= t;
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mode = InflateBlockMode.LENS; // get length of stored block
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break;
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case 1: // fixed
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int[] bl = new int[1];
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int[] bd = new int[1];
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int[][] tl = new int[1][];
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int[][] td = new int[1][];
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InfTree.inflate_trees_fixed(bl, bd, tl, td, _codec);
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codes.Init(bl[0], bd[0], tl[0], 0, td[0], 0);
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b >>= 3; k -= 3;
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mode = InflateBlockMode.CODES;
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break;
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case 2: // dynamic
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b >>= 3; k -= 3;
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mode = InflateBlockMode.TABLE;
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break;
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case 3: // illegal
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b >>= 3; k -= 3;
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mode = InflateBlockMode.BAD;
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_codec.Message = "invalid block type";
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r = ZlibConstants.Z_DATA_ERROR;
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bitb = b; bitk = k;
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_codec.AvailableBytesIn = n;
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_codec.TotalBytesIn += p - _codec.NextIn;
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_codec.NextIn = p;
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writeAt = q;
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return Flush(r);
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}
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break;
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case InflateBlockMode.LENS:
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while (k < (32))
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{
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if (n != 0)
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{
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r = ZlibConstants.Z_OK;
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}
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else
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{
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bitb = b; bitk = k;
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_codec.AvailableBytesIn = n;
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_codec.TotalBytesIn += p - _codec.NextIn;
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_codec.NextIn = p;
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writeAt = q;
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return Flush(r);
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}
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;
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n--;
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b |= (_codec.InputBuffer[p++] & 0xff) << k;
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k += 8;
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}
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if ( ( ((~b)>>16) & 0xffff) != (b & 0xffff))
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{
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mode = InflateBlockMode.BAD;
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_codec.Message = "invalid stored block lengths";
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r = ZlibConstants.Z_DATA_ERROR;
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bitb = b; bitk = k;
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_codec.AvailableBytesIn = n;
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_codec.TotalBytesIn += p - _codec.NextIn;
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_codec.NextIn = p;
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writeAt = q;
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return Flush(r);
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}
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left = (b & 0xffff);
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b = k = 0; // dump bits
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mode = left != 0 ? InflateBlockMode.STORED : (last != 0 ? InflateBlockMode.DRY : InflateBlockMode.TYPE);
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break;
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case InflateBlockMode.STORED:
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if (n == 0)
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{
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bitb = b; bitk = k;
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_codec.AvailableBytesIn = n;
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_codec.TotalBytesIn += p - _codec.NextIn;
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_codec.NextIn = p;
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writeAt = q;
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return Flush(r);
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}
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if (m == 0)
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{
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if (q == end && readAt != 0)
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{
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q = 0; m = (int)(q < readAt ? readAt - q - 1 : end - q);
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}
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if (m == 0)
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{
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writeAt = q;
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r = Flush(r);
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q = writeAt; m = (int)(q < readAt ? readAt - q - 1 : end - q);
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if (q == end && readAt != 0)
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{
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q = 0; m = (int)(q < readAt ? readAt - q - 1 : end - q);
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}
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if (m == 0)
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{
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bitb = b; bitk = k;
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_codec.AvailableBytesIn = n;
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_codec.TotalBytesIn += p - _codec.NextIn;
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_codec.NextIn = p;
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writeAt = q;
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return Flush(r);
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}
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}
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}
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r = ZlibConstants.Z_OK;
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t = left;
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if (t > n)
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t = n;
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if (t > m)
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t = m;
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Array.Copy(_codec.InputBuffer, p, window, q, t);
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p += t; n -= t;
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q += t; m -= t;
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if ((left -= t) != 0)
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break;
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mode = last != 0 ? InflateBlockMode.DRY : InflateBlockMode.TYPE;
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break;
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case InflateBlockMode.TABLE:
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while (k < (14))
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{
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if (n != 0)
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{
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r = ZlibConstants.Z_OK;
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}
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else
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{
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bitb = b; bitk = k;
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_codec.AvailableBytesIn = n;
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_codec.TotalBytesIn += p - _codec.NextIn;
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_codec.NextIn = p;
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writeAt = q;
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return Flush(r);
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}
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n--;
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b |= (_codec.InputBuffer[p++] & 0xff) << k;
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k += 8;
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}
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table = t = (b & 0x3fff);
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if ((t & 0x1f) > 29 || ((t >> 5) & 0x1f) > 29)
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{
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mode = InflateBlockMode.BAD;
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_codec.Message = "too many length or distance symbols";
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r = ZlibConstants.Z_DATA_ERROR;
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bitb = b; bitk = k;
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_codec.AvailableBytesIn = n;
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_codec.TotalBytesIn += p - _codec.NextIn;
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_codec.NextIn = p;
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writeAt = q;
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return Flush(r);
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}
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t = 258 + (t & 0x1f) + ((t >> 5) & 0x1f);
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if (blens == null || blens.Length < t)
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{
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blens = new int[t];
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}
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else
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{
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Array.Clear(blens, 0, t);
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// for (int i = 0; i < t; i++)
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// {
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// blens[i] = 0;
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// }
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}
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b >>= 14;
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k -= 14;
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index = 0;
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mode = InflateBlockMode.BTREE;
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goto case InflateBlockMode.BTREE;
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case InflateBlockMode.BTREE:
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while (index < 4 + (table >> 10))
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{
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while (k < (3))
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{
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if (n != 0)
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{
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r = ZlibConstants.Z_OK;
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}
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else
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{
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bitb = b; bitk = k;
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_codec.AvailableBytesIn = n;
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_codec.TotalBytesIn += p - _codec.NextIn;
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_codec.NextIn = p;
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writeAt = q;
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return Flush(r);
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}
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n--;
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b |= (_codec.InputBuffer[p++] & 0xff) << k;
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k += 8;
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}
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blens[border[index++]] = b & 7;
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b >>= 3; k -= 3;
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}
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while (index < 19)
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{
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blens[border[index++]] = 0;
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}
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bb[0] = 7;
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t = inftree.inflate_trees_bits(blens, bb, tb, hufts, _codec);
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if (t != ZlibConstants.Z_OK)
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{
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r = t;
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if (r == ZlibConstants.Z_DATA_ERROR)
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{
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blens = null;
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mode = InflateBlockMode.BAD;
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}
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bitb = b; bitk = k;
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_codec.AvailableBytesIn = n;
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_codec.TotalBytesIn += p - _codec.NextIn;
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_codec.NextIn = p;
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writeAt = q;
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return Flush(r);
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}
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index = 0;
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mode = InflateBlockMode.DTREE;
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goto case InflateBlockMode.DTREE;
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case InflateBlockMode.DTREE:
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while (true)
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{
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t = table;
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if (!(index < 258 + (t & 0x1f) + ((t >> 5) & 0x1f)))
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{
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break;
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}
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int i, j, c;
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t = bb[0];
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while (k < t)
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{
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if (n != 0)
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{
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r = ZlibConstants.Z_OK;
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}
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else
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{
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bitb = b; bitk = k;
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_codec.AvailableBytesIn = n;
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_codec.TotalBytesIn += p - _codec.NextIn;
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_codec.NextIn = p;
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writeAt = q;
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return Flush(r);
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}
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n--;
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b |= (_codec.InputBuffer[p++] & 0xff) << k;
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k += 8;
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}
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t = hufts[(tb[0] + (b & InternalInflateConstants.InflateMask[t])) * 3 + 1];
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c = hufts[(tb[0] + (b & InternalInflateConstants.InflateMask[t])) * 3 + 2];
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if (c < 16)
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{
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b >>= t; k -= t;
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blens[index++] = c;
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}
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else
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{
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// c == 16..18
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i = c == 18 ? 7 : c - 14;
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j = c == 18 ? 11 : 3;
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while (k < (t + i))
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{
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if (n != 0)
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{
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r = ZlibConstants.Z_OK;
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}
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else
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{
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bitb = b; bitk = k;
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_codec.AvailableBytesIn = n;
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_codec.TotalBytesIn += p - _codec.NextIn;
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_codec.NextIn = p;
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writeAt = q;
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return Flush(r);
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}
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n--;
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b |= (_codec.InputBuffer[p++] & 0xff) << k;
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k += 8;
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}
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b >>= t; k -= t;
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j += (b & InternalInflateConstants.InflateMask[i]);
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b >>= i; k -= i;
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i = index;
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t = table;
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if (i + j > 258 + (t & 0x1f) + ((t >> 5) & 0x1f) || (c == 16 && i < 1))
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{
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blens = null;
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mode = InflateBlockMode.BAD;
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_codec.Message = "invalid bit length repeat";
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r = ZlibConstants.Z_DATA_ERROR;
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bitb = b; bitk = k;
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_codec.AvailableBytesIn = n;
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_codec.TotalBytesIn += p - _codec.NextIn;
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_codec.NextIn = p;
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writeAt = q;
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return Flush(r);
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}
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c = (c == 16) ? blens[i-1] : 0;
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do
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{
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blens[i++] = c;
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}
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while (--j != 0);
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index = i;
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}
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}
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tb[0] = -1;
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{
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int[] bl = new int[] { 9 }; // must be <= 9 for lookahead assumptions
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int[] bd = new int[] { 6 }; // must be <= 9 for lookahead assumptions
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int[] tl = new int[1];
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int[] td = new int[1];
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t = table;
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t = inftree.inflate_trees_dynamic(257 + (t & 0x1f), 1 + ((t >> 5) & 0x1f), blens, bl, bd, tl, td, hufts, _codec);
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if (t != ZlibConstants.Z_OK)
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|
{
|
|
if (t == ZlibConstants.Z_DATA_ERROR)
|
|
{
|
|
blens = null;
|
|
mode = InflateBlockMode.BAD;
|
|
}
|
|
r = t;
|
|
|
|
bitb = b; bitk = k;
|
|
_codec.AvailableBytesIn = n;
|
|
_codec.TotalBytesIn += p - _codec.NextIn;
|
|
_codec.NextIn = p;
|
|
writeAt = q;
|
|
return Flush(r);
|
|
}
|
|
codes.Init(bl[0], bd[0], hufts, tl[0], hufts, td[0]);
|
|
}
|
|
mode = InflateBlockMode.CODES;
|
|
goto case InflateBlockMode.CODES;
|
|
|
|
case InflateBlockMode.CODES:
|
|
bitb = b; bitk = k;
|
|
_codec.AvailableBytesIn = n;
|
|
_codec.TotalBytesIn += p - _codec.NextIn;
|
|
_codec.NextIn = p;
|
|
writeAt = q;
|
|
|
|
r = codes.Process(this, r);
|
|
if (r != ZlibConstants.Z_STREAM_END)
|
|
{
|
|
return Flush(r);
|
|
}
|
|
|
|
r = ZlibConstants.Z_OK;
|
|
p = _codec.NextIn;
|
|
n = _codec.AvailableBytesIn;
|
|
b = bitb;
|
|
k = bitk;
|
|
q = writeAt;
|
|
m = (int)(q < readAt ? readAt - q - 1 : end - q);
|
|
|
|
if (last == 0)
|
|
{
|
|
mode = InflateBlockMode.TYPE;
|
|
break;
|
|
}
|
|
mode = InflateBlockMode.DRY;
|
|
goto case InflateBlockMode.DRY;
|
|
|
|
case InflateBlockMode.DRY:
|
|
writeAt = q;
|
|
r = Flush(r);
|
|
q = writeAt; m = (int)(q < readAt ? readAt - q - 1 : end - q);
|
|
if (readAt != writeAt)
|
|
{
|
|
bitb = b; bitk = k;
|
|
_codec.AvailableBytesIn = n;
|
|
_codec.TotalBytesIn += p - _codec.NextIn;
|
|
_codec.NextIn = p;
|
|
writeAt = q;
|
|
return Flush(r);
|
|
}
|
|
mode = InflateBlockMode.DONE;
|
|
goto case InflateBlockMode.DONE;
|
|
|
|
case InflateBlockMode.DONE:
|
|
r = ZlibConstants.Z_STREAM_END;
|
|
bitb = b;
|
|
bitk = k;
|
|
_codec.AvailableBytesIn = n;
|
|
_codec.TotalBytesIn += p - _codec.NextIn;
|
|
_codec.NextIn = p;
|
|
writeAt = q;
|
|
return Flush(r);
|
|
|
|
case InflateBlockMode.BAD:
|
|
r = ZlibConstants.Z_DATA_ERROR;
|
|
|
|
bitb = b; bitk = k;
|
|
_codec.AvailableBytesIn = n;
|
|
_codec.TotalBytesIn += p - _codec.NextIn;
|
|
_codec.NextIn = p;
|
|
writeAt = q;
|
|
return Flush(r);
|
|
|
|
|
|
default:
|
|
r = ZlibConstants.Z_STREAM_ERROR;
|
|
|
|
bitb = b; bitk = k;
|
|
_codec.AvailableBytesIn = n;
|
|
_codec.TotalBytesIn += p - _codec.NextIn;
|
|
_codec.NextIn = p;
|
|
writeAt = q;
|
|
return Flush(r);
|
|
}
|
|
}
|
|
}
|
|
|
|
|
|
internal void Free()
|
|
{
|
|
Reset();
|
|
window = null;
|
|
hufts = null;
|
|
}
|
|
|
|
internal void SetDictionary(byte[] d, int start, int n)
|
|
{
|
|
Array.Copy(d, start, window, 0, n);
|
|
readAt = writeAt = n;
|
|
}
|
|
|
|
// Returns true if inflate is currently at the end of a block generated
|
|
// by Z_SYNC_FLUSH or Z_FULL_FLUSH.
|
|
internal int SyncPoint()
|
|
{
|
|
return mode == InflateBlockMode.LENS ? 1 : 0;
|
|
}
|
|
|
|
// copy as much as possible from the sliding window to the output area
|
|
internal int Flush(int r)
|
|
{
|
|
int nBytes;
|
|
|
|
for (int pass=0; pass < 2; pass++)
|
|
{
|
|
if (pass==0)
|
|
{
|
|
// compute number of bytes to copy as far as end of window
|
|
nBytes = (int)((readAt <= writeAt ? writeAt : end) - readAt);
|
|
}
|
|
else
|
|
{
|
|
// compute bytes to copy
|
|
nBytes = writeAt - readAt;
|
|
}
|
|
|
|
// workitem 8870
|
|
if (nBytes == 0)
|
|
{
|
|
if (r == ZlibConstants.Z_BUF_ERROR)
|
|
r = ZlibConstants.Z_OK;
|
|
return r;
|
|
}
|
|
|
|
if (nBytes > _codec.AvailableBytesOut)
|
|
nBytes = _codec.AvailableBytesOut;
|
|
|
|
if (nBytes != 0 && r == ZlibConstants.Z_BUF_ERROR)
|
|
r = ZlibConstants.Z_OK;
|
|
|
|
// update counters
|
|
_codec.AvailableBytesOut -= nBytes;
|
|
_codec.TotalBytesOut += nBytes;
|
|
|
|
// update check information
|
|
if (checkfn != null)
|
|
_codec._Adler32 = check = Adler.Adler32(check, window, readAt, nBytes);
|
|
|
|
// copy as far as end of window
|
|
Array.Copy(window, readAt, _codec.OutputBuffer, _codec.NextOut, nBytes);
|
|
_codec.NextOut += nBytes;
|
|
readAt += nBytes;
|
|
|
|
// see if more to copy at beginning of window
|
|
if (readAt == end && pass == 0)
|
|
{
|
|
// wrap pointers
|
|
readAt = 0;
|
|
if (writeAt == end)
|
|
writeAt = 0;
|
|
}
|
|
else pass++;
|
|
}
|
|
|
|
// done
|
|
return r;
|
|
}
|
|
}
|
|
|
|
|
|
internal static class InternalInflateConstants
|
|
{
|
|
// And'ing with mask[n] masks the lower n bits
|
|
internal static readonly int[] InflateMask = new int[] {
|
|
0x00000000, 0x00000001, 0x00000003, 0x00000007,
|
|
0x0000000f, 0x0000001f, 0x0000003f, 0x0000007f,
|
|
0x000000ff, 0x000001ff, 0x000003ff, 0x000007ff,
|
|
0x00000fff, 0x00001fff, 0x00003fff, 0x00007fff, 0x0000ffff };
|
|
}
|
|
|
|
|
|
sealed class InflateCodes
|
|
{
|
|
// waiting for "i:"=input,
|
|
// "o:"=output,
|
|
// "x:"=nothing
|
|
private const int START = 0; // x: set up for LEN
|
|
private const int LEN = 1; // i: get length/literal/eob next
|
|
private const int LENEXT = 2; // i: getting length extra (have base)
|
|
private const int DIST = 3; // i: get distance next
|
|
private const int DISTEXT = 4; // i: getting distance extra
|
|
private const int COPY = 5; // o: copying bytes in window, waiting for space
|
|
private const int LIT = 6; // o: got literal, waiting for output space
|
|
private const int WASH = 7; // o: got eob, possibly still output waiting
|
|
private const int END = 8; // x: got eob and all data flushed
|
|
private const int BADCODE = 9; // x: got error
|
|
|
|
internal int mode; // current inflate_codes mode
|
|
|
|
// mode dependent information
|
|
internal int len;
|
|
|
|
internal int[] tree; // pointer into tree
|
|
internal int tree_index = 0;
|
|
internal int need; // bits needed
|
|
|
|
internal int lit;
|
|
|
|
// if EXT or COPY, where and how much
|
|
internal int bitsToGet; // bits to get for extra
|
|
internal int dist; // distance back to copy from
|
|
|
|
internal byte lbits; // ltree bits decoded per branch
|
|
internal byte dbits; // dtree bits decoder per branch
|
|
internal int[] ltree; // literal/length/eob tree
|
|
internal int ltree_index; // literal/length/eob tree
|
|
internal int[] dtree; // distance tree
|
|
internal int dtree_index; // distance tree
|
|
|
|
internal InflateCodes()
|
|
{
|
|
}
|
|
|
|
internal void Init(int bl, int bd, int[] tl, int tl_index, int[] td, int td_index)
|
|
{
|
|
mode = START;
|
|
lbits = (byte)bl;
|
|
dbits = (byte)bd;
|
|
ltree = tl;
|
|
ltree_index = tl_index;
|
|
dtree = td;
|
|
dtree_index = td_index;
|
|
tree = null;
|
|
}
|
|
|
|
internal int Process(InflateBlocks blocks, int r)
|
|
{
|
|
int j; // temporary storage
|
|
int tindex; // temporary pointer
|
|
int e; // extra bits or operation
|
|
int b = 0; // bit buffer
|
|
int k = 0; // bits in bit buffer
|
|
int p = 0; // input data pointer
|
|
int n; // bytes available there
|
|
int q; // output window write pointer
|
|
int m; // bytes to end of window or read pointer
|
|
int f; // pointer to copy strings from
|
|
|
|
ZlibCodec z = blocks._codec;
|
|
|
|
// copy input/output information to locals (UPDATE macro restores)
|
|
p = z.NextIn;
|
|
n = z.AvailableBytesIn;
|
|
b = blocks.bitb;
|
|
k = blocks.bitk;
|
|
q = blocks.writeAt; m = q < blocks.readAt ? blocks.readAt - q - 1 : blocks.end - q;
|
|
|
|
// process input and output based on current state
|
|
while (true)
|
|
{
|
|
switch (mode)
|
|
{
|
|
// waiting for "i:"=input, "o:"=output, "x:"=nothing
|
|
case START: // x: set up for LEN
|
|
if (m >= 258 && n >= 10)
|
|
{
|
|
blocks.bitb = b; blocks.bitk = k;
|
|
z.AvailableBytesIn = n;
|
|
z.TotalBytesIn += p - z.NextIn;
|
|
z.NextIn = p;
|
|
blocks.writeAt = q;
|
|
r = InflateFast(lbits, dbits, ltree, ltree_index, dtree, dtree_index, blocks, z);
|
|
|
|
p = z.NextIn;
|
|
n = z.AvailableBytesIn;
|
|
b = blocks.bitb;
|
|
k = blocks.bitk;
|
|
q = blocks.writeAt; m = q < blocks.readAt ? blocks.readAt - q - 1 : blocks.end - q;
|
|
|
|
if (r != ZlibConstants.Z_OK)
|
|
{
|
|
mode = (r == ZlibConstants.Z_STREAM_END) ? WASH : BADCODE;
|
|
break;
|
|
}
|
|
}
|
|
need = lbits;
|
|
tree = ltree;
|
|
tree_index = ltree_index;
|
|
|
|
mode = LEN;
|
|
goto case LEN;
|
|
|
|
case LEN: // i: get length/literal/eob next
|
|
j = need;
|
|
|
|
while (k < j)
|
|
{
|
|
if (n != 0)
|
|
r = ZlibConstants.Z_OK;
|
|
else
|
|
{
|
|
blocks.bitb = b; blocks.bitk = k;
|
|
z.AvailableBytesIn = n;
|
|
z.TotalBytesIn += p - z.NextIn;
|
|
z.NextIn = p;
|
|
blocks.writeAt = q;
|
|
return blocks.Flush(r);
|
|
}
|
|
n--;
|
|
b |= (z.InputBuffer[p++] & 0xff) << k;
|
|
k += 8;
|
|
}
|
|
|
|
tindex = (tree_index + (b & InternalInflateConstants.InflateMask[j])) * 3;
|
|
|
|
b >>= (tree[tindex + 1]);
|
|
k -= (tree[tindex + 1]);
|
|
|
|
e = tree[tindex];
|
|
|
|
if (e == 0)
|
|
{
|
|
// literal
|
|
lit = tree[tindex + 2];
|
|
mode = LIT;
|
|
break;
|
|
}
|
|
if ((e & 16) != 0)
|
|
{
|
|
// length
|
|
bitsToGet = e & 15;
|
|
len = tree[tindex + 2];
|
|
mode = LENEXT;
|
|
break;
|
|
}
|
|
if ((e & 64) == 0)
|
|
{
|
|
// next table
|
|
need = e;
|
|
tree_index = tindex / 3 + tree[tindex + 2];
|
|
break;
|
|
}
|
|
if ((e & 32) != 0)
|
|
{
|
|
// end of block
|
|
mode = WASH;
|
|
break;
|
|
}
|
|
mode = BADCODE; // invalid code
|
|
z.Message = "invalid literal/length code";
|
|
r = ZlibConstants.Z_DATA_ERROR;
|
|
|
|
blocks.bitb = b; blocks.bitk = k;
|
|
z.AvailableBytesIn = n;
|
|
z.TotalBytesIn += p - z.NextIn;
|
|
z.NextIn = p;
|
|
blocks.writeAt = q;
|
|
return blocks.Flush(r);
|
|
|
|
|
|
case LENEXT: // i: getting length extra (have base)
|
|
j = bitsToGet;
|
|
|
|
while (k < j)
|
|
{
|
|
if (n != 0)
|
|
r = ZlibConstants.Z_OK;
|
|
else
|
|
{
|
|
blocks.bitb = b; blocks.bitk = k;
|
|
z.AvailableBytesIn = n; z.TotalBytesIn += p - z.NextIn; z.NextIn = p;
|
|
blocks.writeAt = q;
|
|
return blocks.Flush(r);
|
|
}
|
|
n--; b |= (z.InputBuffer[p++] & 0xff) << k;
|
|
k += 8;
|
|
}
|
|
|
|
len += (b & InternalInflateConstants.InflateMask[j]);
|
|
|
|
b >>= j;
|
|
k -= j;
|
|
|
|
need = dbits;
|
|
tree = dtree;
|
|
tree_index = dtree_index;
|
|
mode = DIST;
|
|
goto case DIST;
|
|
|
|
case DIST: // i: get distance next
|
|
j = need;
|
|
|
|
while (k < j)
|
|
{
|
|
if (n != 0)
|
|
r = ZlibConstants.Z_OK;
|
|
else
|
|
{
|
|
blocks.bitb = b; blocks.bitk = k;
|
|
z.AvailableBytesIn = n; z.TotalBytesIn += p - z.NextIn; z.NextIn = p;
|
|
blocks.writeAt = q;
|
|
return blocks.Flush(r);
|
|
}
|
|
n--; b |= (z.InputBuffer[p++] & 0xff) << k;
|
|
k += 8;
|
|
}
|
|
|
|
tindex = (tree_index + (b & InternalInflateConstants.InflateMask[j])) * 3;
|
|
|
|
b >>= tree[tindex + 1];
|
|
k -= tree[tindex + 1];
|
|
|
|
e = (tree[tindex]);
|
|
if ((e & 0x10) != 0)
|
|
{
|
|
// distance
|
|
bitsToGet = e & 15;
|
|
dist = tree[tindex + 2];
|
|
mode = DISTEXT;
|
|
break;
|
|
}
|
|
if ((e & 64) == 0)
|
|
{
|
|
// next table
|
|
need = e;
|
|
tree_index = tindex / 3 + tree[tindex + 2];
|
|
break;
|
|
}
|
|
mode = BADCODE; // invalid code
|
|
z.Message = "invalid distance code";
|
|
r = ZlibConstants.Z_DATA_ERROR;
|
|
|
|
blocks.bitb = b; blocks.bitk = k;
|
|
z.AvailableBytesIn = n; z.TotalBytesIn += p - z.NextIn; z.NextIn = p;
|
|
blocks.writeAt = q;
|
|
return blocks.Flush(r);
|
|
|
|
|
|
case DISTEXT: // i: getting distance extra
|
|
j = bitsToGet;
|
|
|
|
while (k < j)
|
|
{
|
|
if (n != 0)
|
|
r = ZlibConstants.Z_OK;
|
|
else
|
|
{
|
|
blocks.bitb = b; blocks.bitk = k;
|
|
z.AvailableBytesIn = n; z.TotalBytesIn += p - z.NextIn; z.NextIn = p;
|
|
blocks.writeAt = q;
|
|
return blocks.Flush(r);
|
|
}
|
|
n--; b |= (z.InputBuffer[p++] & 0xff) << k;
|
|
k += 8;
|
|
}
|
|
|
|
dist += (b & InternalInflateConstants.InflateMask[j]);
|
|
|
|
b >>= j;
|
|
k -= j;
|
|
|
|
mode = COPY;
|
|
goto case COPY;
|
|
|
|
case COPY: // o: copying bytes in window, waiting for space
|
|
f = q - dist;
|
|
while (f < 0)
|
|
{
|
|
// modulo window size-"while" instead
|
|
f += blocks.end; // of "if" handles invalid distances
|
|
}
|
|
while (len != 0)
|
|
{
|
|
if (m == 0)
|
|
{
|
|
if (q == blocks.end && blocks.readAt != 0)
|
|
{
|
|
q = 0; m = q < blocks.readAt ? blocks.readAt - q - 1 : blocks.end - q;
|
|
}
|
|
if (m == 0)
|
|
{
|
|
blocks.writeAt = q; r = blocks.Flush(r);
|
|
q = blocks.writeAt; m = q < blocks.readAt ? blocks.readAt - q - 1 : blocks.end - q;
|
|
|
|
if (q == blocks.end && blocks.readAt != 0)
|
|
{
|
|
q = 0; m = q < blocks.readAt ? blocks.readAt - q - 1 : blocks.end - q;
|
|
}
|
|
|
|
if (m == 0)
|
|
{
|
|
blocks.bitb = b; blocks.bitk = k;
|
|
z.AvailableBytesIn = n;
|
|
z.TotalBytesIn += p - z.NextIn;
|
|
z.NextIn = p;
|
|
blocks.writeAt = q;
|
|
return blocks.Flush(r);
|
|
}
|
|
}
|
|
}
|
|
|
|
blocks.window[q++] = blocks.window[f++]; m--;
|
|
|
|
if (f == blocks.end)
|
|
f = 0;
|
|
len--;
|
|
}
|
|
mode = START;
|
|
break;
|
|
|
|
case LIT: // o: got literal, waiting for output space
|
|
if (m == 0)
|
|
{
|
|
if (q == blocks.end && blocks.readAt != 0)
|
|
{
|
|
q = 0; m = q < blocks.readAt ? blocks.readAt - q - 1 : blocks.end - q;
|
|
}
|
|
if (m == 0)
|
|
{
|
|
blocks.writeAt = q; r = blocks.Flush(r);
|
|
q = blocks.writeAt; m = q < blocks.readAt ? blocks.readAt - q - 1 : blocks.end - q;
|
|
|
|
if (q == blocks.end && blocks.readAt != 0)
|
|
{
|
|
q = 0; m = q < blocks.readAt ? blocks.readAt - q - 1 : blocks.end - q;
|
|
}
|
|
if (m == 0)
|
|
{
|
|
blocks.bitb = b; blocks.bitk = k;
|
|
z.AvailableBytesIn = n; z.TotalBytesIn += p - z.NextIn; z.NextIn = p;
|
|
blocks.writeAt = q;
|
|
return blocks.Flush(r);
|
|
}
|
|
}
|
|
}
|
|
r = ZlibConstants.Z_OK;
|
|
|
|
blocks.window[q++] = (byte)lit; m--;
|
|
|
|
mode = START;
|
|
break;
|
|
|
|
case WASH: // o: got eob, possibly more output
|
|
if (k > 7)
|
|
{
|
|
// return unused byte, if any
|
|
k -= 8;
|
|
n++;
|
|
p--; // can always return one
|
|
}
|
|
|
|
blocks.writeAt = q; r = blocks.Flush(r);
|
|
q = blocks.writeAt; m = q < blocks.readAt ? blocks.readAt - q - 1 : blocks.end - q;
|
|
|
|
if (blocks.readAt != blocks.writeAt)
|
|
{
|
|
blocks.bitb = b; blocks.bitk = k;
|
|
z.AvailableBytesIn = n; z.TotalBytesIn += p - z.NextIn; z.NextIn = p;
|
|
blocks.writeAt = q;
|
|
return blocks.Flush(r);
|
|
}
|
|
mode = END;
|
|
goto case END;
|
|
|
|
case END:
|
|
r = ZlibConstants.Z_STREAM_END;
|
|
blocks.bitb = b; blocks.bitk = k;
|
|
z.AvailableBytesIn = n; z.TotalBytesIn += p - z.NextIn; z.NextIn = p;
|
|
blocks.writeAt = q;
|
|
return blocks.Flush(r);
|
|
|
|
case BADCODE: // x: got error
|
|
|
|
r = ZlibConstants.Z_DATA_ERROR;
|
|
|
|
blocks.bitb = b; blocks.bitk = k;
|
|
z.AvailableBytesIn = n; z.TotalBytesIn += p - z.NextIn; z.NextIn = p;
|
|
blocks.writeAt = q;
|
|
return blocks.Flush(r);
|
|
|
|
default:
|
|
r = ZlibConstants.Z_STREAM_ERROR;
|
|
|
|
blocks.bitb = b; blocks.bitk = k;
|
|
z.AvailableBytesIn = n; z.TotalBytesIn += p - z.NextIn; z.NextIn = p;
|
|
blocks.writeAt = q;
|
|
return blocks.Flush(r);
|
|
}
|
|
}
|
|
}
|
|
|
|
|
|
// Called with number of bytes left to write in window at least 258
|
|
// (the maximum string length) and number of input bytes available
|
|
// at least ten. The ten bytes are six bytes for the longest length/
|
|
// distance pair plus four bytes for overloading the bit buffer.
|
|
|
|
internal int InflateFast(int bl, int bd, int[] tl, int tl_index, int[] td, int td_index, InflateBlocks s, ZlibCodec z)
|
|
{
|
|
int t; // temporary pointer
|
|
int[] tp; // temporary pointer
|
|
int tp_index; // temporary pointer
|
|
int e; // extra bits or operation
|
|
int b; // bit buffer
|
|
int k; // bits in bit buffer
|
|
int p; // input data pointer
|
|
int n; // bytes available there
|
|
int q; // output window write pointer
|
|
int m; // bytes to end of window or read pointer
|
|
int ml; // mask for literal/length tree
|
|
int md; // mask for distance tree
|
|
int c; // bytes to copy
|
|
int d; // distance back to copy from
|
|
int r; // copy source pointer
|
|
|
|
int tp_index_t_3; // (tp_index+t)*3
|
|
|
|
// load input, output, bit values
|
|
p = z.NextIn; n = z.AvailableBytesIn; b = s.bitb; k = s.bitk;
|
|
q = s.writeAt; m = q < s.readAt ? s.readAt - q - 1 : s.end - q;
|
|
|
|
// initialize masks
|
|
ml = InternalInflateConstants.InflateMask[bl];
|
|
md = InternalInflateConstants.InflateMask[bd];
|
|
|
|
// do until not enough input or output space for fast loop
|
|
do
|
|
{
|
|
// assume called with m >= 258 && n >= 10
|
|
// get literal/length code
|
|
while (k < (20))
|
|
{
|
|
// max bits for literal/length code
|
|
n--;
|
|
b |= (z.InputBuffer[p++] & 0xff) << k; k += 8;
|
|
}
|
|
|
|
t = b & ml;
|
|
tp = tl;
|
|
tp_index = tl_index;
|
|
tp_index_t_3 = (tp_index + t) * 3;
|
|
if ((e = tp[tp_index_t_3]) == 0)
|
|
{
|
|
b >>= (tp[tp_index_t_3 + 1]); k -= (tp[tp_index_t_3 + 1]);
|
|
|
|
s.window[q++] = (byte)tp[tp_index_t_3 + 2];
|
|
m--;
|
|
continue;
|
|
}
|
|
do
|
|
{
|
|
|
|
b >>= (tp[tp_index_t_3 + 1]); k -= (tp[tp_index_t_3 + 1]);
|
|
|
|
if ((e & 16) != 0)
|
|
{
|
|
e &= 15;
|
|
c = tp[tp_index_t_3 + 2] + ((int)b & InternalInflateConstants.InflateMask[e]);
|
|
|
|
b >>= e; k -= e;
|
|
|
|
// decode distance base of block to copy
|
|
while (k < 15)
|
|
{
|
|
// max bits for distance code
|
|
n--;
|
|
b |= (z.InputBuffer[p++] & 0xff) << k; k += 8;
|
|
}
|
|
|
|
t = b & md;
|
|
tp = td;
|
|
tp_index = td_index;
|
|
tp_index_t_3 = (tp_index + t) * 3;
|
|
e = tp[tp_index_t_3];
|
|
|
|
do
|
|
{
|
|
|
|
b >>= (tp[tp_index_t_3 + 1]); k -= (tp[tp_index_t_3 + 1]);
|
|
|
|
if ((e & 16) != 0)
|
|
{
|
|
// get extra bits to add to distance base
|
|
e &= 15;
|
|
while (k < e)
|
|
{
|
|
// get extra bits (up to 13)
|
|
n--;
|
|
b |= (z.InputBuffer[p++] & 0xff) << k; k += 8;
|
|
}
|
|
|
|
d = tp[tp_index_t_3 + 2] + (b & InternalInflateConstants.InflateMask[e]);
|
|
|
|
b >>= e; k -= e;
|
|
|
|
// do the copy
|
|
m -= c;
|
|
if (q >= d)
|
|
{
|
|
// offset before dest
|
|
// just copy
|
|
r = q - d;
|
|
if (q - r > 0 && 2 > (q - r))
|
|
{
|
|
s.window[q++] = s.window[r++]; // minimum count is three,
|
|
s.window[q++] = s.window[r++]; // so unroll loop a little
|
|
c -= 2;
|
|
}
|
|
else
|
|
{
|
|
Array.Copy(s.window, r, s.window, q, 2);
|
|
q += 2; r += 2; c -= 2;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
// else offset after destination
|
|
r = q - d;
|
|
do
|
|
{
|
|
r += s.end; // force pointer in window
|
|
}
|
|
while (r < 0); // covers invalid distances
|
|
e = s.end - r;
|
|
if (c > e)
|
|
{
|
|
// if source crosses,
|
|
c -= e; // wrapped copy
|
|
if (q - r > 0 && e > (q - r))
|
|
{
|
|
do
|
|
{
|
|
s.window[q++] = s.window[r++];
|
|
}
|
|
while (--e != 0);
|
|
}
|
|
else
|
|
{
|
|
Array.Copy(s.window, r, s.window, q, e);
|
|
q += e; r += e; e = 0;
|
|
}
|
|
r = 0; // copy rest from start of window
|
|
}
|
|
}
|
|
|
|
// copy all or what's left
|
|
if (q - r > 0 && c > (q - r))
|
|
{
|
|
do
|
|
{
|
|
s.window[q++] = s.window[r++];
|
|
}
|
|
while (--c != 0);
|
|
}
|
|
else
|
|
{
|
|
Array.Copy(s.window, r, s.window, q, c);
|
|
q += c; r += c; c = 0;
|
|
}
|
|
break;
|
|
}
|
|
else if ((e & 64) == 0)
|
|
{
|
|
t += tp[tp_index_t_3 + 2];
|
|
t += (b & InternalInflateConstants.InflateMask[e]);
|
|
tp_index_t_3 = (tp_index + t) * 3;
|
|
e = tp[tp_index_t_3];
|
|
}
|
|
else
|
|
{
|
|
z.Message = "invalid distance code";
|
|
|
|
c = z.AvailableBytesIn - n; c = (k >> 3) < c ? k >> 3 : c; n += c; p -= c; k -= (c << 3);
|
|
|
|
s.bitb = b; s.bitk = k;
|
|
z.AvailableBytesIn = n; z.TotalBytesIn += p - z.NextIn; z.NextIn = p;
|
|
s.writeAt = q;
|
|
|
|
return ZlibConstants.Z_DATA_ERROR;
|
|
}
|
|
}
|
|
while (true);
|
|
break;
|
|
}
|
|
|
|
if ((e & 64) == 0)
|
|
{
|
|
t += tp[tp_index_t_3 + 2];
|
|
t += (b & InternalInflateConstants.InflateMask[e]);
|
|
tp_index_t_3 = (tp_index + t) * 3;
|
|
if ((e = tp[tp_index_t_3]) == 0)
|
|
{
|
|
b >>= (tp[tp_index_t_3 + 1]); k -= (tp[tp_index_t_3 + 1]);
|
|
s.window[q++] = (byte)tp[tp_index_t_3 + 2];
|
|
m--;
|
|
break;
|
|
}
|
|
}
|
|
else if ((e & 32) != 0)
|
|
{
|
|
c = z.AvailableBytesIn - n; c = (k >> 3) < c ? k >> 3 : c; n += c; p -= c; k -= (c << 3);
|
|
|
|
s.bitb = b; s.bitk = k;
|
|
z.AvailableBytesIn = n; z.TotalBytesIn += p - z.NextIn; z.NextIn = p;
|
|
s.writeAt = q;
|
|
|
|
return ZlibConstants.Z_STREAM_END;
|
|
}
|
|
else
|
|
{
|
|
z.Message = "invalid literal/length code";
|
|
|
|
c = z.AvailableBytesIn - n; c = (k >> 3) < c ? k >> 3 : c; n += c; p -= c; k -= (c << 3);
|
|
|
|
s.bitb = b; s.bitk = k;
|
|
z.AvailableBytesIn = n; z.TotalBytesIn += p - z.NextIn; z.NextIn = p;
|
|
s.writeAt = q;
|
|
|
|
return ZlibConstants.Z_DATA_ERROR;
|
|
}
|
|
}
|
|
while (true);
|
|
}
|
|
while (m >= 258 && n >= 10);
|
|
|
|
// not enough input or output--restore pointers and return
|
|
c = z.AvailableBytesIn - n; c = (k >> 3) < c ? k >> 3 : c; n += c; p -= c; k -= (c << 3);
|
|
|
|
s.bitb = b; s.bitk = k;
|
|
z.AvailableBytesIn = n; z.TotalBytesIn += p - z.NextIn; z.NextIn = p;
|
|
s.writeAt = q;
|
|
|
|
return ZlibConstants.Z_OK;
|
|
}
|
|
}
|
|
|
|
|
|
internal sealed class InflateManager
|
|
{
|
|
// preset dictionary flag in zlib header
|
|
private const int PRESET_DICT = 0x20;
|
|
|
|
private const int Z_DEFLATED = 8;
|
|
|
|
private enum InflateManagerMode
|
|
{
|
|
METHOD = 0, // waiting for method byte
|
|
FLAG = 1, // waiting for flag byte
|
|
DICT4 = 2, // four dictionary check bytes to go
|
|
DICT3 = 3, // three dictionary check bytes to go
|
|
DICT2 = 4, // two dictionary check bytes to go
|
|
DICT1 = 5, // one dictionary check byte to go
|
|
DICT0 = 6, // waiting for inflateSetDictionary
|
|
BLOCKS = 7, // decompressing blocks
|
|
CHECK4 = 8, // four check bytes to go
|
|
CHECK3 = 9, // three check bytes to go
|
|
CHECK2 = 10, // two check bytes to go
|
|
CHECK1 = 11, // one check byte to go
|
|
DONE = 12, // finished check, done
|
|
BAD = 13, // got an error--stay here
|
|
}
|
|
|
|
private InflateManagerMode mode; // current inflate mode
|
|
internal ZlibCodec _codec; // pointer back to this zlib stream
|
|
|
|
// mode dependent information
|
|
internal int method; // if FLAGS, method byte
|
|
|
|
// if CHECK, check values to compare
|
|
internal uint computedCheck; // computed check value
|
|
internal uint expectedCheck; // stream check value
|
|
|
|
// if BAD, inflateSync's marker bytes count
|
|
internal int marker;
|
|
|
|
// mode independent information
|
|
//internal int nowrap; // flag for no wrapper
|
|
private bool _handleRfc1950HeaderBytes = true;
|
|
internal bool HandleRfc1950HeaderBytes
|
|
{
|
|
get { return _handleRfc1950HeaderBytes; }
|
|
set { _handleRfc1950HeaderBytes = value; }
|
|
}
|
|
internal int wbits; // log2(window size) (8..15, defaults to 15)
|
|
|
|
internal InflateBlocks blocks; // current inflate_blocks state
|
|
|
|
public InflateManager() { }
|
|
|
|
public InflateManager(bool expectRfc1950HeaderBytes)
|
|
{
|
|
_handleRfc1950HeaderBytes = expectRfc1950HeaderBytes;
|
|
}
|
|
|
|
internal int Reset()
|
|
{
|
|
_codec.TotalBytesIn = _codec.TotalBytesOut = 0;
|
|
_codec.Message = null;
|
|
mode = HandleRfc1950HeaderBytes ? InflateManagerMode.METHOD : InflateManagerMode.BLOCKS;
|
|
blocks.Reset();
|
|
return ZlibConstants.Z_OK;
|
|
}
|
|
|
|
internal int End()
|
|
{
|
|
if (blocks != null)
|
|
blocks.Free();
|
|
blocks = null;
|
|
return ZlibConstants.Z_OK;
|
|
}
|
|
|
|
internal int Initialize(ZlibCodec codec, int w)
|
|
{
|
|
_codec = codec;
|
|
_codec.Message = null;
|
|
blocks = null;
|
|
|
|
// handle undocumented nowrap option (no zlib header or check)
|
|
//nowrap = 0;
|
|
//if (w < 0)
|
|
//{
|
|
// w = - w;
|
|
// nowrap = 1;
|
|
//}
|
|
|
|
// set window size
|
|
if (w < 8 || w > 15)
|
|
{
|
|
End();
|
|
throw new ZlibException("Bad window size.");
|
|
|
|
//return ZlibConstants.Z_STREAM_ERROR;
|
|
}
|
|
wbits = w;
|
|
|
|
blocks = new InflateBlocks(codec,
|
|
HandleRfc1950HeaderBytes ? this : null,
|
|
1 << w);
|
|
|
|
// reset state
|
|
Reset();
|
|
return ZlibConstants.Z_OK;
|
|
}
|
|
|
|
|
|
internal int Inflate(FlushType flush)
|
|
{
|
|
int b;
|
|
|
|
if (_codec.InputBuffer == null)
|
|
throw new ZlibException("InputBuffer is null. ");
|
|
|
|
// int f = (flush == FlushType.Finish)
|
|
// ? ZlibConstants.Z_BUF_ERROR
|
|
// : ZlibConstants.Z_OK;
|
|
|
|
// workitem 8870
|
|
int f = ZlibConstants.Z_OK;
|
|
int r = ZlibConstants.Z_BUF_ERROR;
|
|
|
|
while (true)
|
|
{
|
|
switch (mode)
|
|
{
|
|
case InflateManagerMode.METHOD:
|
|
if (_codec.AvailableBytesIn == 0) return r;
|
|
r = f;
|
|
_codec.AvailableBytesIn--;
|
|
_codec.TotalBytesIn++;
|
|
if (((method = _codec.InputBuffer[_codec.NextIn++]) & 0xf) != Z_DEFLATED)
|
|
{
|
|
mode = InflateManagerMode.BAD;
|
|
_codec.Message = String.Format("unknown compression method (0x{0:X2})", method);
|
|
marker = 5; // can't try inflateSync
|
|
break;
|
|
}
|
|
if ((method >> 4) + 8 > wbits)
|
|
{
|
|
mode = InflateManagerMode.BAD;
|
|
_codec.Message = String.Format("invalid window size ({0})", (method >> 4) + 8);
|
|
marker = 5; // can't try inflateSync
|
|
break;
|
|
}
|
|
mode = InflateManagerMode.FLAG;
|
|
break;
|
|
|
|
|
|
case InflateManagerMode.FLAG:
|
|
if (_codec.AvailableBytesIn == 0) return r;
|
|
r = f;
|
|
_codec.AvailableBytesIn--;
|
|
_codec.TotalBytesIn++;
|
|
b = (_codec.InputBuffer[_codec.NextIn++]) & 0xff;
|
|
|
|
if ((((method << 8) + b) % 31) != 0)
|
|
{
|
|
mode = InflateManagerMode.BAD;
|
|
_codec.Message = "incorrect header check";
|
|
marker = 5; // can't try inflateSync
|
|
break;
|
|
}
|
|
|
|
mode = ((b & PRESET_DICT) == 0)
|
|
? InflateManagerMode.BLOCKS
|
|
: InflateManagerMode.DICT4;
|
|
break;
|
|
|
|
case InflateManagerMode.DICT4:
|
|
if (_codec.AvailableBytesIn == 0) return r;
|
|
r = f;
|
|
_codec.AvailableBytesIn--;
|
|
_codec.TotalBytesIn++;
|
|
expectedCheck = (uint)((_codec.InputBuffer[_codec.NextIn++] << 24) & 0xff000000);
|
|
mode = InflateManagerMode.DICT3;
|
|
break;
|
|
|
|
case InflateManagerMode.DICT3:
|
|
if (_codec.AvailableBytesIn == 0) return r;
|
|
r = f;
|
|
_codec.AvailableBytesIn--;
|
|
_codec.TotalBytesIn++;
|
|
expectedCheck += (uint)((_codec.InputBuffer[_codec.NextIn++] << 16) & 0x00ff0000);
|
|
mode = InflateManagerMode.DICT2;
|
|
break;
|
|
|
|
case InflateManagerMode.DICT2:
|
|
|
|
if (_codec.AvailableBytesIn == 0) return r;
|
|
r = f;
|
|
_codec.AvailableBytesIn--;
|
|
_codec.TotalBytesIn++;
|
|
expectedCheck += (uint)((_codec.InputBuffer[_codec.NextIn++] << 8) & 0x0000ff00);
|
|
mode = InflateManagerMode.DICT1;
|
|
break;
|
|
|
|
|
|
case InflateManagerMode.DICT1:
|
|
if (_codec.AvailableBytesIn == 0) return r;
|
|
r = f;
|
|
_codec.AvailableBytesIn--; _codec.TotalBytesIn++;
|
|
expectedCheck += (uint)(_codec.InputBuffer[_codec.NextIn++] & 0x000000ff);
|
|
_codec._Adler32 = expectedCheck;
|
|
mode = InflateManagerMode.DICT0;
|
|
return ZlibConstants.Z_NEED_DICT;
|
|
|
|
|
|
case InflateManagerMode.DICT0:
|
|
mode = InflateManagerMode.BAD;
|
|
_codec.Message = "need dictionary";
|
|
marker = 0; // can try inflateSync
|
|
return ZlibConstants.Z_STREAM_ERROR;
|
|
|
|
|
|
case InflateManagerMode.BLOCKS:
|
|
r = blocks.Process(r);
|
|
if (r == ZlibConstants.Z_DATA_ERROR)
|
|
{
|
|
mode = InflateManagerMode.BAD;
|
|
marker = 0; // can try inflateSync
|
|
break;
|
|
}
|
|
|
|
if (r == ZlibConstants.Z_OK) r = f;
|
|
|
|
if (r != ZlibConstants.Z_STREAM_END)
|
|
return r;
|
|
|
|
r = f;
|
|
computedCheck = blocks.Reset();
|
|
if (!HandleRfc1950HeaderBytes)
|
|
{
|
|
mode = InflateManagerMode.DONE;
|
|
return ZlibConstants.Z_STREAM_END;
|
|
}
|
|
mode = InflateManagerMode.CHECK4;
|
|
break;
|
|
|
|
case InflateManagerMode.CHECK4:
|
|
if (_codec.AvailableBytesIn == 0) return r;
|
|
r = f;
|
|
_codec.AvailableBytesIn--;
|
|
_codec.TotalBytesIn++;
|
|
expectedCheck = (uint)((_codec.InputBuffer[_codec.NextIn++] << 24) & 0xff000000);
|
|
mode = InflateManagerMode.CHECK3;
|
|
break;
|
|
|
|
case InflateManagerMode.CHECK3:
|
|
if (_codec.AvailableBytesIn == 0) return r;
|
|
r = f;
|
|
_codec.AvailableBytesIn--; _codec.TotalBytesIn++;
|
|
expectedCheck += (uint)((_codec.InputBuffer[_codec.NextIn++] << 16) & 0x00ff0000);
|
|
mode = InflateManagerMode.CHECK2;
|
|
break;
|
|
|
|
case InflateManagerMode.CHECK2:
|
|
if (_codec.AvailableBytesIn == 0) return r;
|
|
r = f;
|
|
_codec.AvailableBytesIn--;
|
|
_codec.TotalBytesIn++;
|
|
expectedCheck += (uint)((_codec.InputBuffer[_codec.NextIn++] << 8) & 0x0000ff00);
|
|
mode = InflateManagerMode.CHECK1;
|
|
break;
|
|
|
|
case InflateManagerMode.CHECK1:
|
|
if (_codec.AvailableBytesIn == 0) return r;
|
|
r = f;
|
|
_codec.AvailableBytesIn--; _codec.TotalBytesIn++;
|
|
expectedCheck += (uint)(_codec.InputBuffer[_codec.NextIn++] & 0x000000ff);
|
|
if (computedCheck != expectedCheck)
|
|
{
|
|
mode = InflateManagerMode.BAD;
|
|
_codec.Message = "incorrect data check";
|
|
marker = 5; // can't try inflateSync
|
|
break;
|
|
}
|
|
mode = InflateManagerMode.DONE;
|
|
return ZlibConstants.Z_STREAM_END;
|
|
|
|
case InflateManagerMode.DONE:
|
|
return ZlibConstants.Z_STREAM_END;
|
|
|
|
case InflateManagerMode.BAD:
|
|
throw new ZlibException(String.Format("Bad state ({0})", _codec.Message));
|
|
|
|
default:
|
|
throw new ZlibException("Stream error.");
|
|
|
|
}
|
|
}
|
|
}
|
|
|
|
|
|
|
|
internal int SetDictionary(byte[] dictionary)
|
|
{
|
|
int index = 0;
|
|
int length = dictionary.Length;
|
|
if (mode != InflateManagerMode.DICT0)
|
|
throw new ZlibException("Stream error.");
|
|
|
|
if (Adler.Adler32(1, dictionary, 0, dictionary.Length) != _codec._Adler32)
|
|
{
|
|
return ZlibConstants.Z_DATA_ERROR;
|
|
}
|
|
|
|
_codec._Adler32 = Adler.Adler32(0, null, 0, 0);
|
|
|
|
if (length >= (1 << wbits))
|
|
{
|
|
length = (1 << wbits) - 1;
|
|
index = dictionary.Length - length;
|
|
}
|
|
blocks.SetDictionary(dictionary, index, length);
|
|
mode = InflateManagerMode.BLOCKS;
|
|
return ZlibConstants.Z_OK;
|
|
}
|
|
|
|
|
|
private static readonly byte[] mark = new byte[] { 0, 0, 0xff, 0xff };
|
|
|
|
internal int Sync()
|
|
{
|
|
int n; // number of bytes to look at
|
|
int p; // pointer to bytes
|
|
int m; // number of marker bytes found in a row
|
|
long r, w; // temporaries to save total_in and total_out
|
|
|
|
// set up
|
|
if (mode != InflateManagerMode.BAD)
|
|
{
|
|
mode = InflateManagerMode.BAD;
|
|
marker = 0;
|
|
}
|
|
if ((n = _codec.AvailableBytesIn) == 0)
|
|
return ZlibConstants.Z_BUF_ERROR;
|
|
p = _codec.NextIn;
|
|
m = marker;
|
|
|
|
// search
|
|
while (n != 0 && m < 4)
|
|
{
|
|
if (_codec.InputBuffer[p] == mark[m])
|
|
{
|
|
m++;
|
|
}
|
|
else if (_codec.InputBuffer[p] != 0)
|
|
{
|
|
m = 0;
|
|
}
|
|
else
|
|
{
|
|
m = 4 - m;
|
|
}
|
|
p++; n--;
|
|
}
|
|
|
|
// restore
|
|
_codec.TotalBytesIn += p - _codec.NextIn;
|
|
_codec.NextIn = p;
|
|
_codec.AvailableBytesIn = n;
|
|
marker = m;
|
|
|
|
// return no joy or set up to restart on a new block
|
|
if (m != 4)
|
|
{
|
|
return ZlibConstants.Z_DATA_ERROR;
|
|
}
|
|
r = _codec.TotalBytesIn;
|
|
w = _codec.TotalBytesOut;
|
|
Reset();
|
|
_codec.TotalBytesIn = r;
|
|
_codec.TotalBytesOut = w;
|
|
mode = InflateManagerMode.BLOCKS;
|
|
return ZlibConstants.Z_OK;
|
|
}
|
|
|
|
|
|
// Returns true if inflate is currently at the end of a block generated
|
|
// by Z_SYNC_FLUSH or Z_FULL_FLUSH. This function is used by one PPP
|
|
// implementation to provide an additional safety check. PPP uses Z_SYNC_FLUSH
|
|
// but removes the length bytes of the resulting empty stored block. When
|
|
// decompressing, PPP checks that at the end of input packet, inflate is
|
|
// waiting for these length bytes.
|
|
internal int SyncPoint(ZlibCodec z)
|
|
{
|
|
return blocks.SyncPoint();
|
|
}
|
|
}
|
|
} |