Christian Beier
12 years ago
parent
efcdab50cc
commit
98f4037785
@ -0,0 +1,668 @@
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/*
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* JSUnzip
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*
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* Copyright (c) 2011 by Erik Moller
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* All Rights Reserved
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*
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* This software is provided 'as-is', without any express
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* or implied warranty. In no event will the authors be
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* held liable for any damages arising from the use of
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* this software.
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*
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* Permission is granted to anyone to use this software
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* for any purpose, including commercial applications,
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* and to alter it and redistribute it freely, subject to
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* the following restrictions:
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*
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* 1. The origin of this software must not be
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* misrepresented; you must not claim that you
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* wrote the original software. If you use this
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* software in a product, an acknowledgment in
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* the product documentation would be appreciated
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* but is not required.
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*
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* 2. Altered source versions must be plainly marked
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* as such, and must not be misrepresented as
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* being the original software.
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*
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* 3. This notice may not be removed or altered from
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* any source distribution.
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*/
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var tinf;
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function JSUnzip() {
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this.getInt = function(offset, size) {
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switch (size) {
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case 4:
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return (this.data.charCodeAt(offset + 3) & 0xff) << 24 |
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(this.data.charCodeAt(offset + 2) & 0xff) << 16 |
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(this.data.charCodeAt(offset + 1) & 0xff) << 8 |
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(this.data.charCodeAt(offset + 0) & 0xff);
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break;
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case 2:
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return (this.data.charCodeAt(offset + 1) & 0xff) << 8 |
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(this.data.charCodeAt(offset + 0) & 0xff);
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break;
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default:
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return this.data.charCodeAt(offset) & 0xff;
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break;
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}
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};
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this.getDOSDate = function(dosdate, dostime) {
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var day = dosdate & 0x1f;
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var month = ((dosdate >> 5) & 0xf) - 1;
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var year = 1980 + ((dosdate >> 9) & 0x7f)
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var second = (dostime & 0x1f) * 2;
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var minute = (dostime >> 5) & 0x3f;
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hour = (dostime >> 11) & 0x1f;
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return new Date(year, month, day, hour, minute, second);
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}
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this.open = function(data) {
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this.data = data;
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this.files = [];
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if (this.data.length < 22)
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return { 'status' : false, 'error' : 'Invalid data' };
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var endOfCentralDirectory = this.data.length - 22;
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while (endOfCentralDirectory >= 0 && this.getInt(endOfCentralDirectory, 4) != 0x06054b50)
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--endOfCentralDirectory;
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if (endOfCentralDirectory < 0)
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return { 'status' : false, 'error' : 'Invalid data' };
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if (this.getInt(endOfCentralDirectory + 4, 2) != 0 || this.getInt(endOfCentralDirectory + 6, 2) != 0)
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return { 'status' : false, 'error' : 'No multidisk support' };
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var entriesInThisDisk = this.getInt(endOfCentralDirectory + 8, 2);
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var centralDirectoryOffset = this.getInt(endOfCentralDirectory + 16, 4);
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var globalCommentLength = this.getInt(endOfCentralDirectory + 20, 2);
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this.comment = this.data.slice(endOfCentralDirectory + 22, endOfCentralDirectory + 22 + globalCommentLength);
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var fileOffset = centralDirectoryOffset;
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for (var i = 0; i < entriesInThisDisk; ++i) {
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if (this.getInt(fileOffset + 0, 4) != 0x02014b50)
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return { 'status' : false, 'error' : 'Invalid data' };
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if (this.getInt(fileOffset + 6, 2) > 20)
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return { 'status' : false, 'error' : 'Unsupported version' };
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if (this.getInt(fileOffset + 8, 2) & 1)
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return { 'status' : false, 'error' : 'Encryption not implemented' };
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var compressionMethod = this.getInt(fileOffset + 10, 2);
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if (compressionMethod != 0 && compressionMethod != 8)
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return { 'status' : false, 'error' : 'Unsupported compression method' };
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var lastModFileTime = this.getInt(fileOffset + 12, 2);
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var lastModFileDate = this.getInt(fileOffset + 14, 2);
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var lastModifiedDate = this.getDOSDate(lastModFileDate, lastModFileTime);
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var crc = this.getInt(fileOffset + 16, 4);
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// TODO: crc
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var compressedSize = this.getInt(fileOffset + 20, 4);
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var uncompressedSize = this.getInt(fileOffset + 24, 4);
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var fileNameLength = this.getInt(fileOffset + 28, 2);
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var extraFieldLength = this.getInt(fileOffset + 30, 2);
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var fileCommentLength = this.getInt(fileOffset + 32, 2);
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var relativeOffsetOfLocalHeader = this.getInt(fileOffset + 42, 4);
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var fileName = this.data.slice(fileOffset + 46, fileOffset + 46 + fileNameLength);
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var fileComment = this.data.slice(fileOffset + 46 + fileNameLength + extraFieldLength, fileOffset + 46 + fileNameLength + extraFieldLength + fileCommentLength);
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if (this.getInt(relativeOffsetOfLocalHeader + 0, 4) != 0x04034b50)
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return { 'status' : false, 'error' : 'Invalid data' };
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var localFileNameLength = this.getInt(relativeOffsetOfLocalHeader + 26, 2);
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var localExtraFieldLength = this.getInt(relativeOffsetOfLocalHeader + 28, 2);
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var localFileContent = relativeOffsetOfLocalHeader + 30 + localFileNameLength + localExtraFieldLength;
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this.files[fileName] =
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{
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'fileComment' : fileComment,
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'compressionMethod' : compressionMethod,
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'compressedSize' : compressedSize,
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'uncompressedSize' : uncompressedSize,
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'localFileContent' : localFileContent,
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'lastModifiedDate' : lastModifiedDate
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};
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fileOffset += 46 + fileNameLength + extraFieldLength + fileCommentLength;
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}
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return { 'status' : true }
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};
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this.read = function(fileName) {
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var fileInfo = this.files[fileName];
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if (fileInfo) {
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if (fileInfo.compressionMethod == 8) {
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if (!tinf) {
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tinf = new TINF();
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tinf.init();
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}
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var result = tinf.uncompress(this.data, fileInfo.localFileContent);
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if (result.status == tinf.OK)
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return { 'status' : true, 'data' : result.data };
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else
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return { 'status' : false, 'error' : result.error };
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} else {
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return { 'status' : true, 'data' : this.data.slice(fileInfo.localFileContent, fileInfo.localFileContent + fileInfo.uncompressedSize) };
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}
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}
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return { 'status' : false, 'error' : "File '" + fileName + "' doesn't exist in zip" };
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};
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};
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/*
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* tinflate - tiny inflate
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*
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* Copyright (c) 2003 by Joergen Ibsen / Jibz
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* All Rights Reserved
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*
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* http://www.ibsensoftware.com/
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*
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* This software is provided 'as-is', without any express
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* or implied warranty. In no event will the authors be
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* held liable for any damages arising from the use of
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* this software.
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*
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* Permission is granted to anyone to use this software
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* for any purpose, including commercial applications,
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* and to alter it and redistribute it freely, subject to
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* the following restrictions:
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*
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* 1. The origin of this software must not be
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* misrepresented; you must not claim that you
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* wrote the original software. If you use this
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* software in a product, an acknowledgment in
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* the product documentation would be appreciated
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* but is not required.
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*
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* 2. Altered source versions must be plainly marked
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* as such, and must not be misrepresented as
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* being the original software.
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*
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* 3. This notice may not be removed or altered from
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* any source distribution.
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*/
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/*
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* tinflate javascript port by Erik Moller in May 2011.
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* emoller@opera.com
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*
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* read_bits() patched by mike@imidio.com to allow
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* reading more then 8 bits (needed in some zlib streams)
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*/
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"use strict";
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function TINF() {
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this.OK = 0;
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this.DATA_ERROR = (-3);
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this.WINDOW_SIZE = 32768;
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/* ------------------------------ *
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* -- internal data structures -- *
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* ------------------------------ */
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this.TREE = function() {
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this.table = new Array(16); /* table of code length counts */
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this.trans = new Array(288); /* code -> symbol translation table */
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};
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this.DATA = function(that) {
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this.source = '';
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this.sourceIndex = 0;
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this.tag = 0;
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this.bitcount = 0;
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this.dest = [];
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this.history = [];
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this.ltree = new that.TREE(); /* dynamic length/symbol tree */
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this.dtree = new that.TREE(); /* dynamic distance tree */
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};
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/* --------------------------------------------------- *
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* -- uninitialized global data (static structures) -- *
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* --------------------------------------------------- */
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this.sltree = new this.TREE(); /* fixed length/symbol tree */
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this.sdtree = new this.TREE(); /* fixed distance tree */
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/* extra bits and base tables for length codes */
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this.length_bits = new Array(30);
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this.length_base = new Array(30);
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/* extra bits and base tables for distance codes */
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this.dist_bits = new Array(30);
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this.dist_base = new Array(30);
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/* special ordering of code length codes */
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this.clcidx = [
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16, 17, 18, 0, 8, 7, 9, 6,
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10, 5, 11, 4, 12, 3, 13, 2,
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14, 1, 15
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];
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/* ----------------------- *
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* -- utility functions -- *
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* ----------------------- */
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/* build extra bits and base tables */
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this.build_bits_base = function(bits, base, delta, first)
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{
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var i, sum;
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/* build bits table */
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for (i = 0; i < delta; ++i) bits[i] = 0;
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for (i = 0; i < 30 - delta; ++i) bits[i + delta] = Math.floor(i / delta);
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/* build base table */
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for (sum = first, i = 0; i < 30; ++i)
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{
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base[i] = sum;
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sum += 1 << bits[i];
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}
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}
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/* build the fixed huffman trees */
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this.build_fixed_trees = function(lt, dt)
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{
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var i;
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/* build fixed length tree */
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for (i = 0; i < 7; ++i) lt.table[i] = 0;
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lt.table[7] = 24;
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lt.table[8] = 152;
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lt.table[9] = 112;
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for (i = 0; i < 24; ++i) lt.trans[i] = 256 + i;
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for (i = 0; i < 144; ++i) lt.trans[24 + i] = i;
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for (i = 0; i < 8; ++i) lt.trans[24 + 144 + i] = 280 + i;
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for (i = 0; i < 112; ++i) lt.trans[24 + 144 + 8 + i] = 144 + i;
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/* build fixed distance tree */
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for (i = 0; i < 5; ++i) dt.table[i] = 0;
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dt.table[5] = 32;
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for (i = 0; i < 32; ++i) dt.trans[i] = i;
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}
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/* given an array of code lengths, build a tree */
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this.build_tree = function(t, lengths, loffset, num)
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{
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var offs = new Array(16);
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var i, sum;
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/* clear code length count table */
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for (i = 0; i < 16; ++i) t.table[i] = 0;
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/* scan symbol lengths, and sum code length counts */
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for (i = 0; i < num; ++i) t.table[lengths[loffset + i]]++;
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t.table[0] = 0;
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/* compute offset table for distribution sort */
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for (sum = 0, i = 0; i < 16; ++i)
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{
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offs[i] = sum;
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sum += t.table[i];
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}
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/* create code->symbol translation table (symbols sorted by code) */
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for (i = 0; i < num; ++i)
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{
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if (lengths[loffset + i]) t.trans[offs[lengths[loffset + i]]++] = i;
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}
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}
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/* ---------------------- *
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* -- decode functions -- *
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* ---------------------- */
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/* get one bit from source stream */
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this.getbit = function(d)
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{
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var bit;
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/* check if tag is empty */
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if (!d.bitcount--)
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{
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/* load next tag */
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d.tag = d.source[d.sourceIndex++] & 0xff;
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d.bitcount = 7;
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}
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/* shift bit out of tag */
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bit = d.tag & 0x01;
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d.tag >>= 1;
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return bit;
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}
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/* read a num bit value from a stream and add base */
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this.read_bits = function(d, num, base)
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{
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if (!num)
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return base;
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var val = 0;
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while (d.bitcount < 24) {
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d.tag = d.tag | (d.source[d.sourceIndex++] & 0xff) << d.bitcount;
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d.bitcount += 8;
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}
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val = d.tag & (0xffff >> (16 - num));
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d.tag >>= num;
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d.bitcount -= num;
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return val + base;
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}
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/* given a data stream and a tree, decode a symbol */
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this.decode_symbol = function(d, t)
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{
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while (d.bitcount < 16) {
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d.tag = d.tag | (d.source[d.sourceIndex++] & 0xff) << d.bitcount;
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d.bitcount += 8;
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}
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var sum = 0, cur = 0, len = 0;
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do {
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cur = 2 * cur + ((d.tag & (1 << len)) >> len);
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++len;
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sum += t.table[len];
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cur -= t.table[len];
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} while (cur >= 0);
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d.tag >>= len;
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d.bitcount -= len;
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return t.trans[sum + cur];
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}
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/* given a data stream, decode dynamic trees from it */
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this.decode_trees = function(d, lt, dt)
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{
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var code_tree = new this.TREE();
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var lengths = new Array(288+32);
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var hlit, hdist, hclen;
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var i, num, length;
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/* get 5 bits HLIT (257-286) */
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hlit = this.read_bits(d, 5, 257);
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/* get 5 bits HDIST (1-32) */
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hdist = this.read_bits(d, 5, 1);
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/* get 4 bits HCLEN (4-19) */
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hclen = this.read_bits(d, 4, 4);
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for (i = 0; i < 19; ++i) lengths[i] = 0;
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/* read code lengths for code length alphabet */
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for (i = 0; i < hclen; ++i)
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{
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/* get 3 bits code length (0-7) */
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var clen = this.read_bits(d, 3, 0);
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lengths[this.clcidx[i]] = clen;
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}
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/* build code length tree */
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this.build_tree(code_tree, lengths, 0, 19);
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/* decode code lengths for the dynamic trees */
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for (num = 0; num < hlit + hdist; )
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{
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var sym = this.decode_symbol(d, code_tree);
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switch (sym)
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{
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case 16:
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/* copy previous code length 3-6 times (read 2 bits) */
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{
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var prev = lengths[num - 1];
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for (length = this.read_bits(d, 2, 3); length; --length)
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{
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lengths[num++] = prev;
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}
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}
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break;
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case 17:
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/* repeat code length 0 for 3-10 times (read 3 bits) */
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for (length = this.read_bits(d, 3, 3); length; --length)
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{
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lengths[num++] = 0;
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}
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break;
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case 18:
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/* repeat code length 0 for 11-138 times (read 7 bits) */
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for (length = this.read_bits(d, 7, 11); length; --length)
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{
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lengths[num++] = 0;
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}
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break;
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default:
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/* values 0-15 represent the actual code lengths */
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lengths[num++] = sym;
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break;
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}
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}
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||||
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/* build dynamic trees */
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this.build_tree(lt, lengths, 0, hlit);
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this.build_tree(dt, lengths, hlit, hdist);
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}
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/* ----------------------------- *
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* -- block inflate functions -- *
|
||||
* ----------------------------- */
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/* given a stream and two trees, inflate a block of data */
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||||
this.inflate_block_data = function(d, lt, dt)
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{
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||||
// js optimization.
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var ddest = d.dest;
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var ddestlength = ddest.length;
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||||
|
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while (1)
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{
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var sym = this.decode_symbol(d, lt);
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/* check for end of block */
|
||||
if (sym == 256)
|
||||
{
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return this.OK;
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}
|
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|
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if (sym < 256)
|
||||
{
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ddest[ddestlength++] = sym; // ? String.fromCharCode(sym);
|
||||
d.history.push(sym);
|
||||
} else {
|
||||
|
||||
var length, dist, offs;
|
||||
var i;
|
||||
|
||||
sym -= 257;
|
||||
|
||||
/* possibly get more bits from length code */
|
||||
length = this.read_bits(d, this.length_bits[sym], this.length_base[sym]);
|
||||
|
||||
dist = this.decode_symbol(d, dt);
|
||||
|
||||
/* possibly get more bits from distance code */
|
||||
offs = d.history.length - this.read_bits(d, this.dist_bits[dist], this.dist_base[dist]);
|
||||
|
||||
if (offs < 0)
|
||||
throw ("Invalid zlib offset " + offs);
|
||||
|
||||
/* copy match */
|
||||
for (i = offs; i < offs + length; ++i) {
|
||||
//ddest[ddestlength++] = ddest[i];
|
||||
ddest[ddestlength++] = d.history[i];
|
||||
d.history.push(d.history[i]);
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
/* inflate an uncompressed block of data */
|
||||
this.inflate_uncompressed_block = function(d)
|
||||
{
|
||||
var length, invlength;
|
||||
var i;
|
||||
|
||||
if (d.bitcount > 7) {
|
||||
var overflow = Math.floor(d.bitcount / 8);
|
||||
d.sourceIndex -= overflow;
|
||||
d.bitcount = 0;
|
||||
d.tag = 0;
|
||||
}
|
||||
|
||||
/* get length */
|
||||
length = d.source[d.sourceIndex+1];
|
||||
length = 256*length + d.source[d.sourceIndex];
|
||||
|
||||
/* get one's complement of length */
|
||||
invlength = d.source[d.sourceIndex+3];
|
||||
invlength = 256*invlength + d.source[d.sourceIndex+2];
|
||||
|
||||
/* check length */
|
||||
if (length != (~invlength & 0x0000ffff)) return this.DATA_ERROR;
|
||||
|
||||
d.sourceIndex += 4;
|
||||
|
||||
/* copy block */
|
||||
for (i = length; i; --i) {
|
||||
d.history.push(d.source[d.sourceIndex]);
|
||||
d.dest[d.dest.length] = d.source[d.sourceIndex++];
|
||||
}
|
||||
|
||||
/* make sure we start next block on a byte boundary */
|
||||
d.bitcount = 0;
|
||||
|
||||
return this.OK;
|
||||
}
|
||||
|
||||
/* inflate a block of data compressed with fixed huffman trees */
|
||||
this.inflate_fixed_block = function(d)
|
||||
{
|
||||
/* decode block using fixed trees */
|
||||
return this.inflate_block_data(d, this.sltree, this.sdtree);
|
||||
}
|
||||
|
||||
/* inflate a block of data compressed with dynamic huffman trees */
|
||||
this.inflate_dynamic_block = function(d)
|
||||
{
|
||||
/* decode trees from stream */
|
||||
this.decode_trees(d, d.ltree, d.dtree);
|
||||
|
||||
/* decode block using decoded trees */
|
||||
return this.inflate_block_data(d, d.ltree, d.dtree);
|
||||
}
|
||||
|
||||
/* ---------------------- *
|
||||
* -- public functions -- *
|
||||
* ---------------------- */
|
||||
|
||||
/* initialize global (static) data */
|
||||
this.init = function()
|
||||
{
|
||||
/* build fixed huffman trees */
|
||||
this.build_fixed_trees(this.sltree, this.sdtree);
|
||||
|
||||
/* build extra bits and base tables */
|
||||
this.build_bits_base(this.length_bits, this.length_base, 4, 3);
|
||||
this.build_bits_base(this.dist_bits, this.dist_base, 2, 1);
|
||||
|
||||
/* fix a special case */
|
||||
this.length_bits[28] = 0;
|
||||
this.length_base[28] = 258;
|
||||
|
||||
this.reset();
|
||||
}
|
||||
|
||||
this.reset = function()
|
||||
{
|
||||
this.d = new this.DATA(this);
|
||||
delete this.header;
|
||||
}
|
||||
|
||||
/* inflate stream from source to dest */
|
||||
this.uncompress = function(source, offset)
|
||||
{
|
||||
|
||||
var d = this.d;
|
||||
var bfinal;
|
||||
|
||||
/* initialise data */
|
||||
d.source = source;
|
||||
d.sourceIndex = offset;
|
||||
d.bitcount = 0;
|
||||
|
||||
d.dest = [];
|
||||
|
||||
// Skip zlib header at start of stream
|
||||
if (typeof this.header == 'undefined') {
|
||||
this.header = this.read_bits(d, 16, 0);
|
||||
/* byte 0: 0x78, 7 = 32k window size, 8 = deflate */
|
||||
/* byte 1: check bits for header and other flags */
|
||||
}
|
||||
|
||||
var blocks = 0;
|
||||
|
||||
do {
|
||||
|
||||
var btype;
|
||||
var res;
|
||||
|
||||
/* read final block flag */
|
||||
bfinal = this.getbit(d);
|
||||
|
||||
/* read block type (2 bits) */
|
||||
btype = this.read_bits(d, 2, 0);
|
||||
|
||||
/* decompress block */
|
||||
switch (btype)
|
||||
{
|
||||
case 0:
|
||||
/* decompress uncompressed block */
|
||||
res = this.inflate_uncompressed_block(d);
|
||||
break;
|
||||
case 1:
|
||||
/* decompress block with fixed huffman trees */
|
||||
res = this.inflate_fixed_block(d);
|
||||
break;
|
||||
case 2:
|
||||
/* decompress block with dynamic huffman trees */
|
||||
res = this.inflate_dynamic_block(d);
|
||||
break;
|
||||
default:
|
||||
return { 'status' : this.DATA_ERROR };
|
||||
}
|
||||
|
||||
if (res != this.OK) return { 'status' : this.DATA_ERROR };
|
||||
blocks++;
|
||||
|
||||
} while (!bfinal && d.sourceIndex < d.source.length);
|
||||
|
||||
d.history = d.history.slice(-this.WINDOW_SIZE);
|
||||
|
||||
return { 'status' : this.OK, 'data' : d.dest };
|
||||
}
|
||||
|
||||
};
|
||||
Loading…
Reference in new issue