kopia lustrzana https://github.com/dl2alf/AirScout
1747 wiersze
51 KiB
C#
1747 wiersze
51 KiB
C#
/*
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* Licensed to the Apache Software Foundation (ASF) under one or more
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* contributor license agreements. See the NOTICE file distributed with
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* this work for additional information regarding copyright ownership.
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* The ASF licenses this file to You under the Apache License, Version 2.0
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* (the "License"); you may not use this file except in compliance with
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* the License. You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*
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*/
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/*
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* This package is based on the work done by Keiron Liddle, Aftex Software
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* <keiron@aftexsw.com> to whom the Ant project is very grateful for his
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* great code.
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*/
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using System;
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using System.Collections;
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using System.IO;
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using Org.BouncyCastle.Utilities;
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namespace Org.BouncyCastle.Apache.Bzip2
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{
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/**
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* An output stream that compresses into the BZip2 format (with the file
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* header chars) into another stream.
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*
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* @author <a href="mailto:keiron@aftexsw.com">Keiron Liddle</a>
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*
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* TODO: Update to BZip2 1.0.1
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* <b>NB:</b> note this class has been modified to add a leading BZ to the
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* start of the BZIP2 stream to make it compatible with other PGP programs.
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*/
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public class CBZip2OutputStream : Stream
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{
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protected const int SETMASK = 1 << 21;
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protected const int CLEARMASK = ~SETMASK;
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protected const int GREATER_ICOST = 15;
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protected const int LESSER_ICOST = 0;
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protected const int SMALL_THRESH = 20;
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protected const int DEPTH_THRESH = 10;
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private bool finished;
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private static void Panic()
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{
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throw new InvalidOperationException();
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}
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private void MakeMaps()
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{
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int i;
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nInUse = 0;
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for (i = 0; i < 256; i++)
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{
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if (inUse[i])
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{
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seqToUnseq[nInUse] = (char) i;
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unseqToSeq[i] = (char) nInUse;
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nInUse++;
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}
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}
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}
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protected static void HbMakeCodeLengths(byte[] len, int[] freq, int alphaSize, int maxLen)
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{
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/*
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Nodes and heap entries run from 1. Entry 0
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for both the heap and nodes is a sentinel.
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*/
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int[] heap = new int[BZip2Constants.MAX_ALPHA_SIZE + 2];
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int[] weight = new int[BZip2Constants.MAX_ALPHA_SIZE * 2];
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int[] parent = new int[BZip2Constants.MAX_ALPHA_SIZE * 2];
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for (int i = 0; i < alphaSize; i++)
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{
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weight[i + 1] = (freq[i] == 0 ? 1 : freq[i]) << 8;
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}
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while (true)
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{
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int nNodes = alphaSize;
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int nHeap = 0;
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heap[0] = 0;
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weight[0] = 0;
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parent[0] = -2;
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for (int i = 1; i <= alphaSize; i++)
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{
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parent[i] = -1;
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heap[++nHeap] = i;
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{
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int zz = nHeap;
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int tmp = heap[zz];
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while (weight[tmp] < weight[heap[zz >> 1]])
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{
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heap[zz] = heap[zz >> 1];
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zz >>= 1;
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}
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heap[zz] = tmp;
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}
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}
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if (!(nHeap < (BZip2Constants.MAX_ALPHA_SIZE + 2)))
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{
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Panic();
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}
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while (nHeap > 1)
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{
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int n1 = heap[1];
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heap[1] = heap[nHeap--];
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{
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int zz = 1;
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int tmp = heap[zz];
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while (true) {
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int yy = zz << 1;
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if (yy > nHeap)
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break;
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if (yy < nHeap
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&& weight[heap[yy + 1]] < weight[heap[yy]])
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{
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yy++;
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}
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if (weight[tmp] < weight[heap[yy]])
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break;
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heap[zz] = heap[yy];
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zz = yy;
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}
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heap[zz] = tmp;
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}
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int n2 = heap[1];
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heap[1] = heap[nHeap--];
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{
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int zz = 1;
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int tmp = heap[zz];
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while (true)
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{
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int yy = zz << 1;
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if (yy > nHeap)
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break;
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if (yy < nHeap
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&& weight[heap[yy + 1]] < weight[heap[yy]])
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{
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yy++;
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}
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if (weight[tmp] < weight[heap[yy]])
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break;
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heap[zz] = heap[yy];
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zz = yy;
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}
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heap[zz] = tmp;
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}
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nNodes++;
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parent[n1] = parent[n2] = nNodes;
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weight[nNodes] = (int)((uint)((weight[n1] & 0xffffff00)
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+ (weight[n2] & 0xffffff00))
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| (uint)(1 + (((weight[n1] & 0x000000ff) >
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(weight[n2] & 0x000000ff)) ?
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(weight[n1] & 0x000000ff) :
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(weight[n2] & 0x000000ff))));
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parent[nNodes] = -1;
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heap[++nHeap] = nNodes;
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{
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int zz = nHeap;
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int tmp = heap[zz];
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while (weight[tmp] < weight[heap[zz >> 1]])
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{
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heap[zz] = heap[zz >> 1];
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zz >>= 1;
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}
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heap[zz] = tmp;
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}
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}
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if (!(nNodes < (BZip2Constants.MAX_ALPHA_SIZE * 2)))
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{
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Panic();
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}
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bool tooLong = false;
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for (int i = 1; i <= alphaSize; i++)
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{
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int j = 0;
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int k = i;
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while (parent[k] >= 0)
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{
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k = parent[k];
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j++;
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}
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len[i - 1] = (byte)j;
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if (j > maxLen)
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{
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tooLong = true;
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}
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}
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if (!tooLong)
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break;
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for (int i = 1; i < alphaSize; i++)
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{
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int j = weight[i] >> 8;
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j = 1 + (j / 2);
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weight[i] = j << 8;
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}
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}
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}
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/*
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* number of characters in the block
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*/
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int count;
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/*
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index in zptr[] of original string after sorting.
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*/
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int origPtr;
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/*
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always: in the range 0 .. 9.
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The current block size is 100000 * this number.
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*/
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readonly int blockSize100k;
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private int allowableBlockSize;
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bool blockRandomised;
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int bsBuff;
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int bsLive;
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readonly CRC mCrc = new CRC();
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private bool[] inUse = new bool[256];
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private int nInUse;
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private char[] seqToUnseq = new char[256];
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private char[] unseqToSeq = new char[256];
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private char[] selector = new char[BZip2Constants.MAX_SELECTORS];
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private char[] selectorMtf = new char[BZip2Constants.MAX_SELECTORS];
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private byte[] blockBytes;
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private ushort[] quadrantShorts;
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private int[] zptr;
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private int[] szptr;
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private int[] ftab;
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private int nMTF;
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private int[] mtfFreq = new int[BZip2Constants.MAX_ALPHA_SIZE];
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/*
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* Used when sorting. If too many long comparisons
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* happen, we stop sorting, randomise the block
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* slightly, and try again.
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*/
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private int workFactor;
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private int workDone;
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private int workLimit;
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private bool firstAttempt;
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private int currentByte = -1;
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private int runLength = 0;
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public CBZip2OutputStream(Stream outStream)
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: this(outStream, 9)
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{
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}
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public CBZip2OutputStream(Stream outStream, int blockSize)
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{
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blockBytes = null;
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quadrantShorts = null;
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zptr = null;
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ftab = null;
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outStream.WriteByte((byte)'B');
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outStream.WriteByte((byte)'Z');
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BsSetStream(outStream);
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workFactor = 50;
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if (blockSize > 9) {
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blockSize = 9;
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}
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if (blockSize < 1) {
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blockSize = 1;
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}
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blockSize100k = blockSize;
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AllocateCompressStructures();
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Initialize();
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InitBlock();
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}
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/**
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*
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* modified by Oliver Merkel, 010128
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*
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*/
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public override void WriteByte(byte b)
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{
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if (currentByte == b)
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{
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runLength++;
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if (runLength > 254)
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{
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WriteRun();
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currentByte = -1;
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runLength = 0;
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}
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}
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else if (currentByte == -1)
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{
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currentByte = b;
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runLength++;
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}
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else
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{
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WriteRun();
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runLength = 1;
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currentByte = b;
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}
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}
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private void WriteRun()
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{
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if (count > allowableBlockSize)
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{
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EndBlock();
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InitBlock();
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}
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inUse[currentByte] = true;
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for (int i = 0; i < runLength; i++)
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{
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mCrc.UpdateCRC(currentByte);
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}
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switch (runLength)
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{
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case 1:
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blockBytes[++count] = (byte)currentByte;
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break;
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case 2:
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blockBytes[++count] = (byte)currentByte;
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blockBytes[++count] = (byte)currentByte;
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break;
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case 3:
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blockBytes[++count] = (byte)currentByte;
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blockBytes[++count] = (byte)currentByte;
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blockBytes[++count] = (byte)currentByte;
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break;
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default:
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inUse[runLength - 4] = true;
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blockBytes[++count] = (byte)currentByte;
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blockBytes[++count] = (byte)currentByte;
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blockBytes[++count] = (byte)currentByte;
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blockBytes[++count] = (byte)currentByte;
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blockBytes[++count] = (byte)(runLength - 4);
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break;
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}
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}
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bool closed = false;
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// protected void Finalize() {
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// Close();
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// }
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#if PORTABLE
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protected override void Dispose(bool disposing)
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{
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if (disposing)
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{
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if (closed)
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return;
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Finish();
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closed = true;
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Platform.Dispose(this.bsStream);
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}
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base.Dispose(disposing);
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}
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#else
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public override void Close()
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{
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if (closed)
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return;
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Finish();
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closed = true;
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Platform.Dispose(this.bsStream);
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base.Close();
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}
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#endif
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public void Finish()
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{
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if (finished)
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return;
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if (runLength > 0)
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{
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WriteRun();
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}
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currentByte = -1;
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if (count > 0)
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{
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EndBlock();
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}
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EndCompression();
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finished = true;
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Flush();
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}
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public override void Flush()
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{
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bsStream.Flush();
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}
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private int blockCRC, combinedCRC;
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private void Initialize()
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{
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/* Write `magic' bytes h indicating file-format == huffmanised,
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followed by a digit indicating blockSize100k.
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*/
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BsPutUChar('h');
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BsPutUChar('0' + blockSize100k);
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combinedCRC = 0;
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}
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private void InitBlock()
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{
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mCrc.InitialiseCRC();
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count = 0;
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for (int i = 0; i < 256; i++)
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{
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inUse[i] = false;
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}
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/* 20 is just a paranoia constant */
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allowableBlockSize = BZip2Constants.baseBlockSize * blockSize100k - 20;
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}
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private void EndBlock()
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{
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blockCRC = mCrc.GetFinalCRC();
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combinedCRC = Integers.RotateLeft(combinedCRC, 1) ^ blockCRC;
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/* sort the block and establish posn of original string */
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DoReversibleTransformation();
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/*
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A 6-byte block header, the value chosen arbitrarily
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as 0x314159265359 :-). A 32 bit value does not really
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give a strong enough guarantee that the value will not
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appear by chance in the compressed datastream. Worst-case
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probability of this event, for a 900k block, is about
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2.0e-3 for 32 bits, 1.0e-5 for 40 bits and 4.0e-8 for 48 bits.
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For a compressed file of size 100Gb -- about 100000 blocks --
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only a 48-bit marker will do. NB: normal compression/
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decompression do *not* rely on these statistical properties.
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They are only important when trying to recover blocks from
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damaged files.
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*/
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BsPutUChar(0x31);
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BsPutUChar(0x41);
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BsPutUChar(0x59);
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BsPutUChar(0x26);
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BsPutUChar(0x53);
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BsPutUChar(0x59);
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/* Now the block's CRC, so it is in a known place. */
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BsPutint(blockCRC);
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/* Now a single bit indicating randomisation. */
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BsW(1, blockRandomised ? 1 : 0);
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/* Finally, block's contents proper. */
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MoveToFrontCodeAndSend();
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}
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private void EndCompression() {
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/*
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Now another magic 48-bit number, 0x177245385090, to
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indicate the end of the last block. (Sqrt(pi), if
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you want to know. I did want to use e, but it contains
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too much repetition -- 27 18 28 18 28 46 -- for me
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to feel statistically comfortable. Call me paranoid.)
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*/
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BsPutUChar(0x17);
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BsPutUChar(0x72);
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BsPutUChar(0x45);
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BsPutUChar(0x38);
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BsPutUChar(0x50);
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BsPutUChar(0x90);
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BsPutint(combinedCRC);
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BsFinishedWithStream();
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}
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private void HbAssignCodes(int[] code, byte[] length, int minLen, int maxLen, int alphaSize)
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{
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int vec = 0;
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for (int n = minLen; n <= maxLen; n++)
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{
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for (int i = 0; i < alphaSize; i++)
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{
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if (length[i] == n)
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{
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code[i] = vec;
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vec++;
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}
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}
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vec <<= 1;
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}
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}
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private void BsSetStream(Stream f)
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{
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bsStream = f;
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bsLive = 0;
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bsBuff = 0;
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}
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private void BsFinishedWithStream()
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{
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while (bsLive > 0)
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{
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bsStream.WriteByte((byte)(bsBuff >> 24)); // write 8-bit
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bsBuff <<= 8;
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bsLive -= 8;
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}
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}
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private void BsW(int n, int v)
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{
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while (bsLive >= 8)
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{
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bsStream.WriteByte((byte)(bsBuff >> 24)); // write 8-bit
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bsBuff <<= 8;
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bsLive -= 8;
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}
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bsBuff |= v << (32 - bsLive - n);
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bsLive += n;
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}
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private void BsPutUChar(int c)
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{
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BsW(8, c);
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}
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private void BsPutint(int u)
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{
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//BsW(8, (u >> 24) & 0xff);
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//BsW(8, (u >> 16) & 0xff);
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//BsW(8, (u >> 8) & 0xff);
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//BsW(8, u & 0xff);
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BsW(16, (u >> 16) & 0xFFFF);
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BsW(16, u & 0xFFFF);
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}
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private void BsPutIntVS(int numBits, int c)
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{
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BsW(numBits, c);
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}
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private void SendMTFValues()
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{
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byte[][] len = CBZip2InputStream.InitByteArray(BZip2Constants.N_GROUPS, BZip2Constants.MAX_ALPHA_SIZE);
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|
|
int v, t, i, j, gs, ge, bt, bc, iter;
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|
int nSelectors = 0, alphaSize, minLen, maxLen, selCtr;
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|
int nGroups;
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alphaSize = nInUse + 2;
|
|
for (t = 0; t < BZip2Constants.N_GROUPS; t++)
|
|
{
|
|
byte[] len_t = len[t];
|
|
for (v = 0; v < alphaSize; v++)
|
|
{
|
|
len_t[v] = GREATER_ICOST;
|
|
}
|
|
}
|
|
|
|
/* Decide how many coding tables to use */
|
|
if (nMTF <= 0)
|
|
{
|
|
Panic();
|
|
}
|
|
|
|
if (nMTF < 200)
|
|
{
|
|
nGroups = 2;
|
|
}
|
|
else if (nMTF < 600)
|
|
{
|
|
nGroups = 3;
|
|
}
|
|
else if (nMTF < 1200)
|
|
{
|
|
nGroups = 4;
|
|
}
|
|
else if (nMTF < 2400)
|
|
{
|
|
nGroups = 5;
|
|
}
|
|
else
|
|
{
|
|
nGroups = 6;
|
|
}
|
|
|
|
/* Generate an initial set of coding tables */
|
|
{
|
|
int tFreq, aFreq;
|
|
|
|
int nPart = nGroups;
|
|
int remF = nMTF;
|
|
gs = 0;
|
|
while (nPart > 0)
|
|
{
|
|
tFreq = remF / nPart;
|
|
ge = gs - 1;
|
|
aFreq = 0;
|
|
while (aFreq < tFreq && ge < alphaSize - 1)
|
|
{
|
|
aFreq += mtfFreq[++ge];
|
|
}
|
|
|
|
if (ge > gs && nPart != nGroups && nPart != 1
|
|
&& ((nGroups - nPart) % 2 == 1))
|
|
{
|
|
aFreq -= mtfFreq[ge--];
|
|
}
|
|
|
|
byte[] len_np = len[nPart - 1];
|
|
for (v = 0; v < alphaSize; v++)
|
|
{
|
|
if (v >= gs && v <= ge)
|
|
{
|
|
len_np[v] = LESSER_ICOST;
|
|
}
|
|
else
|
|
{
|
|
len_np[v] = GREATER_ICOST;
|
|
}
|
|
}
|
|
|
|
nPart--;
|
|
gs = ge + 1;
|
|
remF -= aFreq;
|
|
}
|
|
}
|
|
|
|
int[][] rfreq = CBZip2InputStream.InitIntArray(BZip2Constants.N_GROUPS, BZip2Constants.MAX_ALPHA_SIZE);
|
|
int[] fave = new int[BZip2Constants.N_GROUPS];
|
|
short[] cost = new short[BZip2Constants.N_GROUPS];
|
|
byte[] len_0 = len[0];
|
|
byte[] len_1 = len[1];
|
|
byte[] len_2 = len[2];
|
|
byte[] len_3 = len[3];
|
|
byte[] len_4 = len[4];
|
|
byte[] len_5 = len[5];
|
|
|
|
/*
|
|
Iterate up to N_ITERS times to improve the tables.
|
|
*/
|
|
for (iter = 0; iter < BZip2Constants.N_ITERS; iter++)
|
|
{
|
|
for (t = 0; t < nGroups; t++)
|
|
{
|
|
fave[t] = 0;
|
|
|
|
int[] rfreq_t = rfreq[t];
|
|
for (v = 0; v < alphaSize; v++)
|
|
{
|
|
rfreq_t[v] = 0;
|
|
}
|
|
}
|
|
|
|
nSelectors = 0;
|
|
gs = 0;
|
|
while (gs < nMTF)
|
|
{
|
|
/* Set group start & end marks. */
|
|
|
|
/*
|
|
* Calculate the cost of this group as coded by each of the coding tables.
|
|
*/
|
|
|
|
ge = System.Math.Min(gs + BZip2Constants.G_SIZE - 1, nMTF - 1);
|
|
|
|
if (nGroups == 6)
|
|
{
|
|
short cost0 = 0, cost1 = 0, cost2 = 0, cost3 = 0, cost4 = 0, cost5 = 0;
|
|
|
|
for (i = gs; i <= ge; i++)
|
|
{
|
|
int icv = szptr[i];
|
|
cost0 += len_0[icv];
|
|
cost1 += len_1[icv];
|
|
cost2 += len_2[icv];
|
|
cost3 += len_3[icv];
|
|
cost4 += len_4[icv];
|
|
cost5 += len_5[icv];
|
|
}
|
|
|
|
cost[0] = cost0;
|
|
cost[1] = cost1;
|
|
cost[2] = cost2;
|
|
cost[3] = cost3;
|
|
cost[4] = cost4;
|
|
cost[5] = cost5;
|
|
}
|
|
else
|
|
{
|
|
for (t = 0; t < nGroups; t++)
|
|
{
|
|
cost[t] = 0;
|
|
}
|
|
|
|
for (i = gs; i <= ge; i++)
|
|
{
|
|
int icv = szptr[i];
|
|
for (t = 0; t < nGroups; t++)
|
|
{
|
|
cost[t] += len[t][icv];
|
|
}
|
|
}
|
|
}
|
|
|
|
/*
|
|
Find the coding table which is best for this group,
|
|
and record its identity in the selector table.
|
|
*/
|
|
bc = 999999999;
|
|
bt = -1;
|
|
for (t = 0; t < nGroups; t++)
|
|
{
|
|
if (cost[t] < bc)
|
|
{
|
|
bc = cost[t];
|
|
bt = t;
|
|
}
|
|
}
|
|
fave[bt]++;
|
|
selector[nSelectors] = (char) bt;
|
|
nSelectors++;
|
|
|
|
/*
|
|
Increment the symbol frequencies for the selected table.
|
|
*/
|
|
int[] rfreq_bt = rfreq[bt];
|
|
for (i = gs; i <= ge; i++)
|
|
{
|
|
rfreq_bt[szptr[i]]++;
|
|
}
|
|
|
|
gs = ge + 1;
|
|
}
|
|
|
|
/*
|
|
Recompute the tables based on the accumulated frequencies.
|
|
*/
|
|
for (t = 0; t < nGroups; t++)
|
|
{
|
|
HbMakeCodeLengths(len[t], rfreq[t], alphaSize, 20);
|
|
}
|
|
}
|
|
|
|
rfreq = null;
|
|
fave = null;
|
|
cost = null;
|
|
|
|
if (!(nGroups < 8))
|
|
{
|
|
Panic();
|
|
}
|
|
if (!(nSelectors < 32768 && nSelectors <= (2 + (900000 / BZip2Constants.G_SIZE))))
|
|
{
|
|
Panic();
|
|
}
|
|
|
|
/* Compute MTF values for the selectors. */
|
|
{
|
|
char[] pos = new char[BZip2Constants.N_GROUPS];
|
|
char ll_i, tmp2, tmp;
|
|
for (i = 0; i < nGroups; i++)
|
|
{
|
|
pos[i] = (char)i;
|
|
}
|
|
for (i = 0; i < nSelectors; i++)
|
|
{
|
|
ll_i = selector[i];
|
|
j = 0;
|
|
tmp = pos[j];
|
|
while (ll_i != tmp)
|
|
{
|
|
j++;
|
|
tmp2 = tmp;
|
|
tmp = pos[j];
|
|
pos[j] = tmp2;
|
|
}
|
|
pos[0] = tmp;
|
|
selectorMtf[i] = (char)j;
|
|
}
|
|
}
|
|
|
|
int[][] code = CBZip2InputStream.InitIntArray(BZip2Constants.N_GROUPS, BZip2Constants.MAX_ALPHA_SIZE);
|
|
|
|
/* Assign actual codes for the tables. */
|
|
for (t = 0; t < nGroups; t++)
|
|
{
|
|
minLen = 32;
|
|
maxLen = 0;
|
|
byte[] len_t = len[t];
|
|
for (i = 0; i < alphaSize; i++)
|
|
{
|
|
int lti = len_t[i];
|
|
if (lti > maxLen)
|
|
{
|
|
maxLen = lti;
|
|
}
|
|
if (lti < minLen)
|
|
{
|
|
minLen = lti;
|
|
}
|
|
}
|
|
if (maxLen > 20)
|
|
{
|
|
Panic();
|
|
}
|
|
if (minLen < 1)
|
|
{
|
|
Panic();
|
|
}
|
|
HbAssignCodes(code[t], len[t], minLen, maxLen, alphaSize);
|
|
}
|
|
|
|
/* Transmit the mapping table. */
|
|
{
|
|
bool[] inUse16 = new bool[16];
|
|
for (i = 0; i < 16; i++)
|
|
{
|
|
inUse16[i] = false;
|
|
int i16 = i * 16;
|
|
for (j = 0; j < 16; j++)
|
|
{
|
|
if (inUse[i16 + j])
|
|
{
|
|
inUse16[i] = true;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
for (i = 0; i < 16; i++)
|
|
{
|
|
BsW(1, inUse16[i] ? 1 : 0);
|
|
}
|
|
|
|
for (i = 0; i < 16; i++)
|
|
{
|
|
if (inUse16[i])
|
|
{
|
|
int i16 = i * 16;
|
|
for (j = 0; j < 16; j++)
|
|
{
|
|
BsW(1, inUse[i16 + j] ? 1 : 0);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
/* Now the selectors. */
|
|
BsW(3, nGroups);
|
|
BsW(15, nSelectors);
|
|
for (i = 0; i < nSelectors; i++)
|
|
{
|
|
int count = selectorMtf[i];
|
|
//for (j = 0; j < count; j++)
|
|
//{
|
|
// BsW(1, 1);
|
|
//}
|
|
//BsW(1, 0);
|
|
while (count >= 24)
|
|
{
|
|
BsW(24, 0xFFFFFF);
|
|
count -= 24;
|
|
}
|
|
BsW(count + 1, (1 << (count + 1)) - 2);
|
|
}
|
|
|
|
/* Now the coding tables. */
|
|
for (t = 0; t < nGroups; t++)
|
|
{
|
|
byte[] len_t = len[t];
|
|
int curr = len_t[0];
|
|
BsW(5, curr);
|
|
for (i = 0; i < alphaSize; i++)
|
|
{
|
|
int lti = len_t[i];
|
|
while (curr < lti)
|
|
{
|
|
BsW(2, 2);
|
|
curr++; /* 10 */
|
|
}
|
|
while (curr > lti)
|
|
{
|
|
BsW(2, 3);
|
|
curr--; /* 11 */
|
|
}
|
|
BsW(1, 0);
|
|
}
|
|
}
|
|
|
|
/* And finally, the block data proper */
|
|
selCtr = 0;
|
|
gs = 0;
|
|
while (gs < nMTF)
|
|
{
|
|
ge = System.Math.Min(gs + BZip2Constants.G_SIZE - 1, nMTF - 1);
|
|
|
|
int selector_selCtr = selector[selCtr];
|
|
byte[] len_selCtr = len[selector_selCtr];
|
|
int[] code_selCtr = code[selector_selCtr];
|
|
|
|
for (i = gs; i <= ge; i++)
|
|
{
|
|
int sfmap_i = szptr[i];
|
|
BsW(len_selCtr[sfmap_i], code_selCtr[sfmap_i]);
|
|
}
|
|
|
|
gs = ge + 1;
|
|
selCtr++;
|
|
}
|
|
if (!(selCtr == nSelectors))
|
|
{
|
|
Panic();
|
|
}
|
|
}
|
|
|
|
private void MoveToFrontCodeAndSend()
|
|
{
|
|
BsPutIntVS(24, origPtr);
|
|
GenerateMTFValues();
|
|
SendMTFValues();
|
|
}
|
|
|
|
private Stream bsStream;
|
|
|
|
private void SimpleSort(int lo, int hi, int d)
|
|
{
|
|
int i, j, h, v;
|
|
|
|
int bigN = hi - lo + 1;
|
|
if (bigN < 2)
|
|
return;
|
|
|
|
int hp = 0;
|
|
while (incs[hp] < bigN)
|
|
{
|
|
hp++;
|
|
}
|
|
hp--;
|
|
|
|
for (; hp >= 0; hp--)
|
|
{
|
|
h = incs[hp];
|
|
|
|
i = lo + h;
|
|
while (i <= hi)
|
|
{
|
|
/* copy 1 */
|
|
v = zptr[i];
|
|
j = i;
|
|
while (FullGtU(zptr[j - h] + d, v + d))
|
|
{
|
|
zptr[j] = zptr[j - h];
|
|
j = j - h;
|
|
if (j <= (lo + h - 1))
|
|
break;
|
|
}
|
|
zptr[j] = v;
|
|
|
|
/* copy 2 */
|
|
if (++i > hi)
|
|
break;
|
|
|
|
v = zptr[i];
|
|
j = i;
|
|
while (FullGtU(zptr[j - h] + d, v + d))
|
|
{
|
|
zptr[j] = zptr[j - h];
|
|
j = j - h;
|
|
if (j <= (lo + h - 1))
|
|
break;
|
|
}
|
|
zptr[j] = v;
|
|
|
|
/* copy 3 */
|
|
if (++i > hi)
|
|
break;
|
|
|
|
v = zptr[i];
|
|
j = i;
|
|
while (FullGtU(zptr[j - h] + d, v + d))
|
|
{
|
|
zptr[j] = zptr[j - h];
|
|
j = j - h;
|
|
if (j <= (lo + h - 1))
|
|
break;
|
|
}
|
|
zptr[j] = v;
|
|
i++;
|
|
|
|
if (workDone > workLimit && firstAttempt)
|
|
return;
|
|
}
|
|
}
|
|
}
|
|
|
|
private void Vswap(int p1, int p2, int n)
|
|
{
|
|
while (--n >= 0)
|
|
{
|
|
int t1 = zptr[p1], t2 = zptr[p2];
|
|
zptr[p1++] = t2;
|
|
zptr[p2++] = t1;
|
|
}
|
|
}
|
|
|
|
private int Med3(int a, int b, int c)
|
|
{
|
|
return a > b
|
|
? (c < b ? b : c > a ? a : c)
|
|
: (c < a ? a : c > b ? b : c);
|
|
}
|
|
|
|
internal class StackElem
|
|
{
|
|
internal int ll;
|
|
internal int hh;
|
|
internal int dd;
|
|
}
|
|
|
|
private static void PushStackElem(IList stack, int stackCount, int ll, int hh, int dd)
|
|
{
|
|
StackElem stackElem;
|
|
if (stackCount < stack.Count)
|
|
{
|
|
stackElem = (StackElem)stack[stackCount];
|
|
}
|
|
else
|
|
{
|
|
stackElem = new StackElem();
|
|
stack.Add(stackElem);
|
|
}
|
|
|
|
stackElem.ll = ll;
|
|
stackElem.hh = hh;
|
|
stackElem.dd = dd;
|
|
}
|
|
|
|
private void QSort3(int loSt, int hiSt, int dSt)
|
|
{
|
|
int unLo, unHi, ltLo, gtHi, n, m;
|
|
|
|
IList stack = Platform.CreateArrayList();
|
|
int stackCount = 0;
|
|
StackElem stackElem;
|
|
|
|
int lo = loSt;
|
|
int hi = hiSt;
|
|
int d = dSt;
|
|
|
|
for (;;)
|
|
{
|
|
if (hi - lo < SMALL_THRESH || d > DEPTH_THRESH)
|
|
{
|
|
SimpleSort(lo, hi, d);
|
|
if (stackCount < 1 || (workDone > workLimit && firstAttempt))
|
|
return;
|
|
|
|
stackElem = (StackElem)stack[--stackCount];
|
|
lo = stackElem.ll;
|
|
hi = stackElem.hh;
|
|
d = stackElem.dd;
|
|
continue;
|
|
}
|
|
|
|
int d1 = d + 1;
|
|
int med = Med3(
|
|
blockBytes[zptr[lo] + d1],
|
|
blockBytes[zptr[hi] + d1],
|
|
blockBytes[zptr[(lo + hi) >> 1] + d1]);
|
|
|
|
unLo = ltLo = lo;
|
|
unHi = gtHi = hi;
|
|
|
|
while (true)
|
|
{
|
|
while (unLo <= unHi)
|
|
{
|
|
int zUnLo = zptr[unLo];
|
|
n = blockBytes[zUnLo + d1] - med;
|
|
if (n > 0)
|
|
break;
|
|
|
|
if (n == 0)
|
|
{
|
|
zptr[unLo] = zptr[ltLo];
|
|
zptr[ltLo++] = zUnLo;
|
|
}
|
|
unLo++;
|
|
}
|
|
while (unLo <= unHi)
|
|
{
|
|
int zUnHi = zptr[unHi];
|
|
n = blockBytes[zUnHi + d1] - med;
|
|
if (n < 0)
|
|
break;
|
|
|
|
if (n == 0)
|
|
{
|
|
zptr[unHi] = zptr[gtHi];
|
|
zptr[gtHi--] = zUnHi;
|
|
}
|
|
unHi--;
|
|
}
|
|
if (unLo > unHi)
|
|
break;
|
|
|
|
int temp = zptr[unLo];
|
|
zptr[unLo++] = zptr[unHi];
|
|
zptr[unHi--] = temp;
|
|
}
|
|
|
|
if (gtHi < ltLo)
|
|
{
|
|
d = d1;
|
|
continue;
|
|
}
|
|
|
|
n = System.Math.Min(ltLo - lo, unLo - ltLo);
|
|
Vswap(lo, unLo - n, n);
|
|
|
|
m = System.Math.Min(hi - gtHi, gtHi - unHi);
|
|
Vswap(unLo, hi - m + 1, m);
|
|
|
|
n = lo + (unLo - ltLo);
|
|
m = hi - (gtHi - unHi);
|
|
|
|
PushStackElem(stack, stackCount++, lo, n - 1, d);
|
|
PushStackElem(stack, stackCount++, n, m, d1);
|
|
|
|
lo = m + 1;
|
|
}
|
|
}
|
|
|
|
private void MainSort()
|
|
{
|
|
int i, j, ss, sb;
|
|
int[] runningOrder = new int[256];
|
|
int[] copy = new int[256];
|
|
bool[] bigDone = new bool[256];
|
|
int c1, c2;
|
|
|
|
/*
|
|
In the various block-sized structures, live data runs
|
|
from 0 to last+NUM_OVERSHOOT_BYTES inclusive. First,
|
|
set up the overshoot area for block.
|
|
*/
|
|
for (i = 0; i < BZip2Constants.NUM_OVERSHOOT_BYTES; i++)
|
|
{
|
|
blockBytes[count + i + 1] = blockBytes[(i % count) + 1];
|
|
}
|
|
for (i = 0; i <= count + BZip2Constants.NUM_OVERSHOOT_BYTES; i++)
|
|
{
|
|
quadrantShorts[i] = 0;
|
|
}
|
|
|
|
blockBytes[0] = blockBytes[count];
|
|
|
|
if (count <= 4000)
|
|
{
|
|
/*
|
|
Use SimpleSort(), since the full sorting mechanism
|
|
has quite a large constant overhead.
|
|
*/
|
|
for (i = 0; i < count; i++)
|
|
{
|
|
zptr[i] = i;
|
|
}
|
|
firstAttempt = false;
|
|
workDone = workLimit = 0;
|
|
SimpleSort(0, count - 1, 0);
|
|
}
|
|
else
|
|
{
|
|
for (i = 0; i <= 255; i++)
|
|
{
|
|
bigDone[i] = false;
|
|
}
|
|
|
|
for (i = 0; i <= 65536; i++)
|
|
{
|
|
ftab[i] = 0;
|
|
}
|
|
|
|
c1 = blockBytes[0];
|
|
for (i = 1; i <= count; i++)
|
|
{
|
|
c2 = blockBytes[i];
|
|
ftab[(c1 << 8) + c2]++;
|
|
c1 = c2;
|
|
}
|
|
|
|
for (i = 0; i < 65536; i++)
|
|
{
|
|
ftab[i + 1] += ftab[i];
|
|
}
|
|
|
|
c1 = blockBytes[1];
|
|
for (i = 0; i < (count - 1); i++)
|
|
{
|
|
c2 = blockBytes[i + 2];
|
|
j = (c1 << 8) + c2;
|
|
c1 = c2;
|
|
ftab[j]--;
|
|
zptr[ftab[j]] = i;
|
|
}
|
|
|
|
j = ((int)blockBytes[count] << 8) + blockBytes[1];
|
|
ftab[j]--;
|
|
zptr[ftab[j]] = count - 1;
|
|
|
|
/*
|
|
Now ftab contains the first loc of every small bucket.
|
|
Calculate the running order, from smallest to largest
|
|
big bucket.
|
|
*/
|
|
|
|
for (i = 0; i <= 255; i++)
|
|
{
|
|
runningOrder[i] = i;
|
|
}
|
|
|
|
{
|
|
int h = 1;
|
|
do
|
|
{
|
|
h = 3 * h + 1;
|
|
}
|
|
while (h <= 256);
|
|
do
|
|
{
|
|
h = h / 3;
|
|
for (i = h; i <= 255; i++)
|
|
{
|
|
int vv = runningOrder[i];
|
|
j = i;
|
|
while ((ftab[(runningOrder[j - h] + 1) << 8] - ftab[runningOrder[j - h] << 8])
|
|
> (ftab[(vv + 1) << 8] - ftab[vv << 8]))
|
|
{
|
|
runningOrder[j] = runningOrder[j - h];
|
|
j = j - h;
|
|
if (j < h)
|
|
break;
|
|
}
|
|
runningOrder[j] = vv;
|
|
}
|
|
}
|
|
while (h != 1);
|
|
}
|
|
|
|
/*
|
|
The main sorting loop.
|
|
*/
|
|
for (i = 0; i <= 255; i++)
|
|
{
|
|
/*
|
|
Process big buckets, starting with the least full.
|
|
*/
|
|
ss = runningOrder[i];
|
|
|
|
/*
|
|
Complete the big bucket [ss] by quicksorting
|
|
any unsorted small buckets [ss, j]. Hopefully
|
|
previous pointer-scanning phases have already
|
|
completed many of the small buckets [ss, j], so
|
|
we don't have to sort them at all.
|
|
*/
|
|
for (j = 0; j <= 255; j++)
|
|
{
|
|
sb = (ss << 8) + j;
|
|
if ((ftab[sb] & SETMASK) != SETMASK)
|
|
{
|
|
int lo = ftab[sb] & CLEARMASK;
|
|
int hi = (ftab[sb + 1] & CLEARMASK) - 1;
|
|
if (hi > lo)
|
|
{
|
|
QSort3(lo, hi, 2);
|
|
if (workDone > workLimit && firstAttempt)
|
|
return;
|
|
}
|
|
ftab[sb] |= SETMASK;
|
|
}
|
|
}
|
|
|
|
/*
|
|
The ss big bucket is now done. Record this fact,
|
|
and update the quadrant descriptors. Remember to
|
|
update quadrants in the overshoot area too, if
|
|
necessary. The "if (i < 255)" test merely skips
|
|
this updating for the last bucket processed, since
|
|
updating for the last bucket is pointless.
|
|
*/
|
|
bigDone[ss] = true;
|
|
|
|
if (i < 255)
|
|
{
|
|
int bbStart = ftab[ss << 8] & CLEARMASK;
|
|
int bbSize = (ftab[(ss + 1) << 8] & CLEARMASK) - bbStart;
|
|
|
|
int shifts = 0;
|
|
while ((bbSize >> shifts) > 65534)
|
|
{
|
|
shifts++;
|
|
}
|
|
|
|
for (j = 0; j < bbSize; j++)
|
|
{
|
|
int a2update = zptr[bbStart + j] + 1;
|
|
ushort qVal = (ushort)(j >> shifts);
|
|
quadrantShorts[a2update] = qVal;
|
|
if (a2update <= BZip2Constants.NUM_OVERSHOOT_BYTES)
|
|
{
|
|
quadrantShorts[a2update + count] = qVal;
|
|
}
|
|
}
|
|
|
|
if (!(((bbSize - 1) >> shifts) <= 65535))
|
|
{
|
|
Panic();
|
|
}
|
|
}
|
|
|
|
/*
|
|
Now scan this big bucket so as to synthesise the
|
|
sorted order for small buckets [t, ss] for all t != ss.
|
|
*/
|
|
for (j = 0; j <= 255; j++)
|
|
{
|
|
copy[j] = ftab[(j << 8) + ss] & CLEARMASK;
|
|
}
|
|
|
|
for (j = ftab[ss << 8] & CLEARMASK;
|
|
j < (ftab[(ss + 1) << 8] & CLEARMASK); j++)
|
|
{
|
|
int zptr_j = zptr[j];
|
|
c1 = blockBytes[zptr_j];
|
|
if (!bigDone[c1])
|
|
{
|
|
zptr[copy[c1]] = (zptr_j == 0 ? count : zptr_j) - 1;
|
|
copy[c1]++;
|
|
}
|
|
}
|
|
|
|
for (j = 0; j <= 255; j++)
|
|
{
|
|
ftab[(j << 8) + ss] |= SETMASK;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
private void RandomiseBlock()
|
|
{
|
|
for (int i = 0; i < 256; i++)
|
|
{
|
|
inUse[i] = false;
|
|
}
|
|
|
|
int rNToGo = 0;
|
|
int rTPos = 0;
|
|
|
|
for (int i = 0; i < count; i++)
|
|
{
|
|
if (rNToGo == 0)
|
|
{
|
|
rNToGo = BZip2Constants.rNums[rTPos];
|
|
|
|
if (++rTPos == 512)
|
|
{
|
|
rTPos = 0;
|
|
}
|
|
}
|
|
rNToGo--;
|
|
blockBytes[i + 1] ^= (byte)((rNToGo == 1) ? 1 : 0);
|
|
|
|
inUse[blockBytes[i + 1]] = true;
|
|
}
|
|
}
|
|
|
|
private void DoReversibleTransformation()
|
|
{
|
|
workLimit = workFactor * (count - 1);
|
|
workDone = 0;
|
|
blockRandomised = false;
|
|
firstAttempt = true;
|
|
|
|
MainSort();
|
|
|
|
if (workDone > workLimit && firstAttempt)
|
|
{
|
|
RandomiseBlock();
|
|
workLimit = workDone = 0;
|
|
blockRandomised = true;
|
|
firstAttempt = false;
|
|
MainSort();
|
|
}
|
|
|
|
origPtr = -1;
|
|
for (int i = 0; i < count; i++)
|
|
{
|
|
if (zptr[i] == 0)
|
|
{
|
|
origPtr = i;
|
|
break;
|
|
}
|
|
}
|
|
|
|
if (origPtr == -1)
|
|
{
|
|
Panic();
|
|
}
|
|
}
|
|
|
|
private bool FullGtU(int i1, int i2)
|
|
{
|
|
int c1, c2;
|
|
|
|
c1 = blockBytes[++i1];
|
|
c2 = blockBytes[++i2];
|
|
if (c1 != c2)
|
|
return c1 > c2;
|
|
|
|
c1 = blockBytes[++i1];
|
|
c2 = blockBytes[++i2];
|
|
if (c1 != c2)
|
|
return c1 > c2;
|
|
|
|
c1 = blockBytes[++i1];
|
|
c2 = blockBytes[++i2];
|
|
if (c1 != c2)
|
|
return c1 > c2;
|
|
|
|
c1 = blockBytes[++i1];
|
|
c2 = blockBytes[++i2];
|
|
if (c1 != c2)
|
|
return c1 > c2;
|
|
|
|
c1 = blockBytes[++i1];
|
|
c2 = blockBytes[++i2];
|
|
if (c1 != c2)
|
|
return c1 > c2;
|
|
|
|
c1 = blockBytes[++i1];
|
|
c2 = blockBytes[++i2];
|
|
if (c1 != c2)
|
|
return c1 > c2;
|
|
|
|
int k = count;
|
|
int s1, s2;
|
|
|
|
do
|
|
{
|
|
c1 = blockBytes[++i1];
|
|
c2 = blockBytes[++i2];
|
|
if (c1 != c2)
|
|
return c1 > c2;
|
|
|
|
s1 = quadrantShorts[i1];
|
|
s2 = quadrantShorts[i2];
|
|
if (s1 != s2)
|
|
return s1 > s2;
|
|
|
|
c1 = blockBytes[++i1];
|
|
c2 = blockBytes[++i2];
|
|
if (c1 != c2)
|
|
return c1 > c2;
|
|
|
|
s1 = quadrantShorts[i1];
|
|
s2 = quadrantShorts[i2];
|
|
if (s1 != s2)
|
|
return s1 > s2;
|
|
|
|
c1 = blockBytes[++i1];
|
|
c2 = blockBytes[++i2];
|
|
if (c1 != c2)
|
|
return c1 > c2;
|
|
|
|
s1 = quadrantShorts[i1];
|
|
s2 = quadrantShorts[i2];
|
|
if (s1 != s2)
|
|
return s1 > s2;
|
|
|
|
c1 = blockBytes[++i1];
|
|
c2 = blockBytes[++i2];
|
|
if (c1 != c2)
|
|
return c1 > c2;
|
|
|
|
s1 = quadrantShorts[i1];
|
|
s2 = quadrantShorts[i2];
|
|
if (s1 != s2)
|
|
return s1 > s2;
|
|
|
|
if (i1 >= count)
|
|
{
|
|
i1 -= count;
|
|
}
|
|
if (i2 >= count)
|
|
{
|
|
i2 -= count;
|
|
}
|
|
|
|
k -= 4;
|
|
workDone++;
|
|
}
|
|
while (k >= 0);
|
|
|
|
return false;
|
|
}
|
|
|
|
/*
|
|
Knuth's increments seem to work better
|
|
than Incerpi-Sedgewick here. Possibly
|
|
because the number of elems to sort is
|
|
usually small, typically <= 20.
|
|
*/
|
|
private static readonly int[] incs = { 1, 4, 13, 40, 121, 364, 1093, 3280, 9841, 29524, 88573, 265720, 797161,
|
|
2391484 };
|
|
|
|
private void AllocateCompressStructures()
|
|
{
|
|
int n = BZip2Constants.baseBlockSize * blockSize100k;
|
|
blockBytes = new byte[(n + 1 + BZip2Constants.NUM_OVERSHOOT_BYTES)];
|
|
quadrantShorts = new ushort[(n + 1 + BZip2Constants.NUM_OVERSHOOT_BYTES)];
|
|
zptr = new int[n];
|
|
ftab = new int[65537];
|
|
|
|
/*
|
|
The back end needs a place to store the MTF values
|
|
whilst it calculates the coding tables. We could
|
|
put them in the zptr array. However, these values
|
|
will fit in a short, so we overlay szptr at the
|
|
start of zptr, in the hope of reducing the number
|
|
of cache misses induced by the multiple traversals
|
|
of the MTF values when calculating coding tables.
|
|
Seems to improve compression speed by about 1%.
|
|
*/
|
|
// NOTE: We can't "overlay" in C#, so we just share zptr
|
|
szptr = zptr;
|
|
}
|
|
|
|
private void GenerateMTFValues()
|
|
{
|
|
char[] yy = new char[256];
|
|
int i, j;
|
|
char tmp;
|
|
char tmp2;
|
|
int zPend;
|
|
int wr;
|
|
int EOB;
|
|
|
|
MakeMaps();
|
|
EOB = nInUse + 1;
|
|
|
|
for (i = 0; i <= EOB; i++)
|
|
{
|
|
mtfFreq[i] = 0;
|
|
}
|
|
|
|
wr = 0;
|
|
zPend = 0;
|
|
for (i = 0; i < nInUse; i++)
|
|
{
|
|
yy[i] = (char) i;
|
|
}
|
|
|
|
for (i = 0; i < count; i++)
|
|
{
|
|
char ll_i;
|
|
|
|
ll_i = unseqToSeq[blockBytes[zptr[i]]];
|
|
|
|
j = 0;
|
|
tmp = yy[j];
|
|
while (ll_i != tmp)
|
|
{
|
|
j++;
|
|
tmp2 = tmp;
|
|
tmp = yy[j];
|
|
yy[j] = tmp2;
|
|
}
|
|
yy[0] = tmp;
|
|
|
|
if (j == 0)
|
|
{
|
|
zPend++;
|
|
}
|
|
else
|
|
{
|
|
if (zPend > 0)
|
|
{
|
|
zPend--;
|
|
while (true)
|
|
{
|
|
switch (zPend % 2)
|
|
{
|
|
case 0:
|
|
szptr[wr++] = BZip2Constants.RUNA;
|
|
mtfFreq[BZip2Constants.RUNA]++;
|
|
break;
|
|
case 1:
|
|
szptr[wr++] = BZip2Constants.RUNB;
|
|
mtfFreq[BZip2Constants.RUNB]++;
|
|
break;
|
|
}
|
|
|
|
if (zPend < 2)
|
|
break;
|
|
|
|
zPend = (zPend - 2) / 2;
|
|
}
|
|
zPend = 0;
|
|
}
|
|
szptr[wr++] = j + 1;
|
|
mtfFreq[j + 1]++;
|
|
}
|
|
}
|
|
|
|
if (zPend > 0)
|
|
{
|
|
zPend--;
|
|
while (true)
|
|
{
|
|
switch (zPend % 2)
|
|
{
|
|
case 0:
|
|
szptr[wr++] = BZip2Constants.RUNA;
|
|
mtfFreq[BZip2Constants.RUNA]++;
|
|
break;
|
|
case 1:
|
|
szptr[wr++] = BZip2Constants.RUNB;
|
|
mtfFreq[BZip2Constants.RUNB]++;
|
|
break;
|
|
}
|
|
|
|
if (zPend < 2)
|
|
break;
|
|
|
|
zPend = (zPend - 2) / 2;
|
|
}
|
|
}
|
|
|
|
szptr[wr++] = EOB;
|
|
mtfFreq[EOB]++;
|
|
|
|
nMTF = wr;
|
|
}
|
|
|
|
public override int Read(byte[] buffer, int offset, int count)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
public override long Seek(long offset, SeekOrigin origin)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
public override void SetLength(long value)
|
|
{
|
|
}
|
|
|
|
public override void Write(byte[] buffer, int offset, int count)
|
|
{
|
|
for (int k = 0; k < count; ++k)
|
|
{
|
|
WriteByte(buffer[k + offset]);
|
|
}
|
|
}
|
|
|
|
public override bool CanRead
|
|
{
|
|
get { return false; }
|
|
}
|
|
|
|
public override bool CanSeek
|
|
{
|
|
get { return false; }
|
|
}
|
|
|
|
public override bool CanWrite
|
|
{
|
|
get { return true; }
|
|
}
|
|
|
|
public override long Length
|
|
{
|
|
get { return 0; }
|
|
}
|
|
|
|
public override long Position
|
|
{
|
|
get { return 0; }
|
|
set {}
|
|
}
|
|
}
|
|
}
|