Skip to content

N
noVNC
Commit 682f33a7 authored by Mike's avatar Mike
Browse files
Options

add javascript zlib

parent e79917c3
Show whitespace changes
Inline Side-by-side
Showing with 645 additions and 0 deletions
include/jsunzip.js 0 → 100755
View file @ 682f33a7
/*
* JSUnzip
*
* Copyright (c) 2011 by Erik Moller
* All Rights Reserved
*
* This software is provided 'as-is', without any express
* or implied warranty. In no event will the authors be
* held liable for any damages arising from the use of
* this software.
*
* Permission is granted to anyone to use this software
* for any purpose, including commercial applications,
* and to alter it and redistribute it freely, subject to
* the following restrictions:
*
* 1. The origin of this software must not be
* misrepresented; you must not claim that you
* wrote the original software. If you use this
* software in a product, an acknowledgment in
* the product documentation would be appreciated
* but is not required.
*
* 2. Altered source versions must be plainly marked
* as such, and must not be misrepresented as
* being the original software.
*
* 3. This notice may not be removed or altered from
* any source distribution.
*/
var tinf;
function JSUnzip() {
this.getInt = function(offset, size) {
switch (size) {
case 4:
return (this.data.charCodeAt(offset + 3) & 0xff) << 24 |
(this.data.charCodeAt(offset + 2) & 0xff) << 16 |
(this.data.charCodeAt(offset + 1) & 0xff) << 8 |
(this.data.charCodeAt(offset + 0) & 0xff);
break;
case 2:
return (this.data.charCodeAt(offset + 1) & 0xff) << 8 |
(this.data.charCodeAt(offset + 0) & 0xff);
break;
default:
return this.data.charCodeAt(offset) & 0xff;
break;
}
};
this.getDOSDate = function(dosdate, dostime) {
var day = dosdate & 0x1f;
var month = ((dosdate >> 5) & 0xf) - 1;
var year = 1980 + ((dosdate >> 9) & 0x7f)
var second = (dostime & 0x1f) * 2;
var minute = (dostime >> 5) & 0x3f;
hour = (dostime >> 11) & 0x1f;
return new Date(year, month, day, hour, minute, second);
}
this.open = function(data) {
this.data = data;
this.files = [];
if (this.data.length < 22)
return { 'status' : false, 'error' : 'Invalid data' };
var endOfCentralDirectory = this.data.length - 22;
while (endOfCentralDirectory >= 0 && this.getInt(endOfCentralDirectory, 4) != 0x06054b50)
--endOfCentralDirectory;
if (endOfCentralDirectory < 0)
return { 'status' : false, 'error' : 'Invalid data' };
if (this.getInt(endOfCentralDirectory + 4, 2) != 0 || this.getInt(endOfCentralDirectory + 6, 2) != 0)
return { 'status' : false, 'error' : 'No multidisk support' };
var entriesInThisDisk = this.getInt(endOfCentralDirectory + 8, 2);
var centralDirectoryOffset = this.getInt(endOfCentralDirectory + 16, 4);
var globalCommentLength = this.getInt(endOfCentralDirectory + 20, 2);
this.comment = this.data.slice(endOfCentralDirectory + 22, endOfCentralDirectory + 22 + globalCommentLength);
var fileOffset = centralDirectoryOffset;
for (var i = 0; i < entriesInThisDisk; ++i) {
if (this.getInt(fileOffset + 0, 4) != 0x02014b50)
return { 'status' : false, 'error' : 'Invalid data' };
if (this.getInt(fileOffset + 6, 2) > 20)
return { 'status' : false, 'error' : 'Unsupported version' };
if (this.getInt(fileOffset + 8, 2) & 1)
return { 'status' : false, 'error' : 'Encryption not implemented' };
var compressionMethod = this.getInt(fileOffset + 10, 2);
if (compressionMethod != 0 && compressionMethod != 8)
return { 'status' : false, 'error' : 'Unsupported compression method' };
var lastModFileTime = this.getInt(fileOffset + 12, 2);
var lastModFileDate = this.getInt(fileOffset + 14, 2);
var lastModifiedDate = this.getDOSDate(lastModFileDate, lastModFileTime);
var crc = this.getInt(fileOffset + 16, 4);
// TODO: crc
var compressedSize = this.getInt(fileOffset + 20, 4);
var uncompressedSize = this.getInt(fileOffset + 24, 4);
var fileNameLength = this.getInt(fileOffset + 28, 2);
var extraFieldLength = this.getInt(fileOffset + 30, 2);
var fileCommentLength = this.getInt(fileOffset + 32, 2);
var relativeOffsetOfLocalHeader = this.getInt(fileOffset + 42, 4);
var fileName = this.data.slice(fileOffset + 46, fileOffset + 46 + fileNameLength);
var fileComment = this.data.slice(fileOffset + 46 + fileNameLength + extraFieldLength, fileOffset + 46 + fileNameLength + extraFieldLength + fileCommentLength);
if (this.getInt(relativeOffsetOfLocalHeader + 0, 4) != 0x04034b50)
return { 'status' : false, 'error' : 'Invalid data' };
var localFileNameLength = this.getInt(relativeOffsetOfLocalHeader + 26, 2);
var localExtraFieldLength = this.getInt(relativeOffsetOfLocalHeader + 28, 2);
var localFileContent = relativeOffsetOfLocalHeader + 30 + localFileNameLength + localExtraFieldLength;
this.files[fileName] =
{
'fileComment' : fileComment,
'compressionMethod' : compressionMethod,
'compressedSize' : compressedSize,
'uncompressedSize' : uncompressedSize,
'localFileContent' : localFileContent,
'lastModifiedDate' : lastModifiedDate
};
fileOffset += 46 + fileNameLength + extraFieldLength + fileCommentLength;
}
return { 'status' : true }
};
this.read = function(fileName) {
var fileInfo = this.files[fileName];
if (fileInfo) {
if (fileInfo.compressionMethod == 8) {
if (!tinf) {
tinf = new TINF();
tinf.init();
}
var result = tinf.uncompress(this.data, fileInfo.localFileContent);
if (result.status == tinf.OK)
return { 'status' : true, 'data' : result.data };
else
return { 'status' : false, 'error' : result.error };
} else {
return { 'status' : true, 'data' : this.data.slice(fileInfo.localFileContent, fileInfo.localFileContent + fileInfo.uncompressedSize) };
}
}
return { 'status' : false, 'error' : "File '" + fileName + "' doesn't exist in zip" };
};
};
/*
* tinflate - tiny inflate
*
* Copyright (c) 2003 by Joergen Ibsen / Jibz
* All Rights Reserved
*
* http://www.ibsensoftware.com/
*
* This software is provided 'as-is', without any express
* or implied warranty. In no event will the authors be
* held liable for any damages arising from the use of
* this software.
*
* Permission is granted to anyone to use this software
* for any purpose, including commercial applications,
* and to alter it and redistribute it freely, subject to
* the following restrictions:
*
* 1. The origin of this software must not be
* misrepresented; you must not claim that you
* wrote the original software. If you use this
* software in a product, an acknowledgment in
* the product documentation would be appreciated
* but is not required.
*
* 2. Altered source versions must be plainly marked
* as such, and must not be misrepresented as
* being the original software.
*
* 3. This notice may not be removed or altered from
* any source distribution.
*/
/*
* tinflate javascript port by Erik Moller in May 2011.
* emoller@opera.com
*/
function TINF() {
this.OK = 0;
this.DATA_ERROR = (-3);
/* ------------------------------ *
* -- internal data structures -- *
* ------------------------------ */
this.TREE = function() {
this.table = new Array(16); /* table of code length counts */
this.trans = new Array(288); /* code -> symbol translation table */
};
this.DATA = function(that) {
this.source = '';
this.sourceIndex = 0;
this.tag = 0;
this.bitcount = 0;
this.dest = [];
this.ltree = new that.TREE(); /* dynamic length/symbol tree */
this.dtree = new that.TREE(); /* dynamic distance tree */
};
/* --------------------------------------------------- *
* -- uninitialized global data (static structures) -- *
* --------------------------------------------------- */
this.sltree = new this.TREE(); /* fixed length/symbol tree */
this.sdtree = new this.TREE(); /* fixed distance tree */
/* extra bits and base tables for length codes */
this.length_bits = new Array(30);
this.length_base = new Array(30);
/* extra bits and base tables for distance codes */
this.dist_bits = new Array(30);
this.dist_base = new Array(30);
/* special ordering of code length codes */
this.clcidx = [
16, 17, 18, 0, 8, 7, 9, 6,
10, 5, 11, 4, 12, 3, 13, 2,
14, 1, 15
];
/* ----------------------- *
* -- utility functions -- *
* ----------------------- */
/* build extra bits and base tables */
this.build_bits_base = function(bits, base, delta, first)
{
var i, sum;
/* build bits table */
for (i = 0; i < delta; ++i) bits[i] = 0;
for (i = 0; i < 30 - delta; ++i) bits[i + delta] = Math.floor(i / delta);
/* build base table */
for (sum = first, i = 0; i < 30; ++i)
{
base[i] = sum;
sum += 1 << bits[i];
}
}
/* build the fixed huffman trees */
this.build_fixed_trees = function(lt, dt)
{
var i;
/* build fixed length tree */
for (i = 0; i < 7; ++i) lt.table[i] = 0;
lt.table[7] = 24;
lt.table[8] = 152;
lt.table[9] = 112;
for (i = 0; i < 24; ++i) lt.trans[i] = 256 + i;
for (i = 0; i < 144; ++i) lt.trans[24 + i] = i;
for (i = 0; i < 8; ++i) lt.trans[24 + 144 + i] = 280 + i;
for (i = 0; i < 112; ++i) lt.trans[24 + 144 + 8 + i] = 144 + i;
/* build fixed distance tree */
for (i = 0; i < 5; ++i) dt.table[i] = 0;
dt.table[5] = 32;
for (i = 0; i < 32; ++i) dt.trans[i] = i;
}
/* given an array of code lengths, build a tree */
this.build_tree = function(t, lengths, loffset, num)
{
var offs = new Array(16);
var i, sum;
/* clear code length count table */
for (i = 0; i < 16; ++i) t.table[i] = 0;
/* scan symbol lengths, and sum code length counts */
for (i = 0; i < num; ++i) t.table[lengths[loffset + i]]++;
t.table[0] = 0;
/* compute offset table for distribution sort */
for (sum = 0, i = 0; i < 16; ++i)
{
offs[i] = sum;
sum += t.table[i];
}
/* create code->symbol translation table (symbols sorted by code) */
for (i = 0; i < num; ++i)
{
if (lengths[loffset + i]) t.trans[offs[lengths[loffset + i]]++] = i;
}
}
/* ---------------------- *
* -- decode functions -- *
* ---------------------- */
/* get one bit from source stream */
this.getbit = function(d)
{
var bit;
/* check if tag is empty */
if (!d.bitcount--)
{
/* load next tag */
d.tag = d.source.charCodeAt(d.sourceIndex++) & 0xff;
d.bitcount = 7;
}
/* shift bit out of tag */
bit = d.tag & 0x01;
d.tag >>= 1;
return bit;
}
/* read a num bit value from a stream and add base */
this.read_bits = function(d, num, base)
{
if (!num)
return base;
var val = 0;
while (d.bitcount < 24) {
d.tag = d.tag | (d.source.charCodeAt(d.sourceIndex++) & 0xff) << d.bitcount;
d.bitcount += 8;
}
val = d.tag & (0xff >> (8 - num));
d.tag >>= num;
d.bitcount -= num;
return val + base;
}
/* given a data stream and a tree, decode a symbol */
this.decode_symbol = function(d, t)
{
while (d.bitcount < 24) {
d.tag = d.tag | (d.source.charCodeAt(d.sourceIndex++) & 0xff) << d.bitcount;
d.bitcount += 8;
}
var sum = 0, cur = 0, len = 0;
do {
cur = 2 * cur + ((d.tag & (1 << len)) >> len);
++len;
sum += t.table[len];
cur -= t.table[len];
} while (cur >= 0);
d.tag >>= len;
d.bitcount -= len;
return t.trans[sum + cur];
}
/* given a data stream, decode dynamic trees from it */
this.decode_trees = function(d, lt, dt)
{
var code_tree = new this.TREE();
lengths = new Array(288+32);
var hlit, hdist, hclen;
var i, num, length;
/* get 5 bits HLIT (257-286) */
hlit = this.read_bits(d, 5, 257);
/* get 5 bits HDIST (1-32) */
hdist = this.read_bits(d, 5, 1);
/* get 4 bits HCLEN (4-19) */
hclen = this.read_bits(d, 4, 4);
for (i = 0; i < 19; ++i) lengths[i] = 0;
/* read code lengths for code length alphabet */
for (i = 0; i < hclen; ++i)
{
/* get 3 bits code length (0-7) */
var clen = this.read_bits(d, 3, 0);
lengths[this.clcidx[i]] = clen;
}
/* build code length tree */
this.build_tree(code_tree, lengths, 0, 19);
/* decode code lengths for the dynamic trees */
for (num = 0; num < hlit + hdist; )
{
var sym = this.decode_symbol(d, code_tree);
switch (sym)
{
case 16:
/* copy previous code length 3-6 times (read 2 bits) */
{
var prev = lengths[num - 1];
for (length = this.read_bits(d, 2, 3); length; --length)
{
lengths[num++] = prev;
}
}
break;
case 17:
/* repeat code length 0 for 3-10 times (read 3 bits) */
for (length = this.read_bits(d, 3, 3); length; --length)
{
lengths[num++] = 0;
}
break;
case 18:
/* repeat code length 0 for 11-138 times (read 7 bits) */
for (length = this.read_bits(d, 7, 11); length; --length)
{
lengths[num++] = 0;
}
break;
default:
/* values 0-15 represent the actual code lengths */
lengths[num++] = sym;
break;
}
}
/* build dynamic trees */
this.build_tree(lt, lengths, 0, hlit);
this.build_tree(dt, lengths, hlit, hdist);
}
/* ----------------------------- *
* -- block inflate functions -- *
* ----------------------------- */
/* given a stream and two trees, inflate a block of data */
this.inflate_block_data = function(d, lt, dt)
{
// js optimization.
var ddest = d.dest;
var ddestlength = ddest.length;
while (1)
{
var sym = this.decode_symbol(d, lt);
/* check for end of block */
if (sym == 256)
{
return this.OK;
}
if (sym < 256)
{
ddest[ddestlength++] = String.fromCharCode(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 = ddestlength - this.read_bits(d, this.dist_bits[dist], this.dist_base[dist]);
/* copy match */
for (i = offs; i < offs + length; ++i) {
ddest[ddestlength++] = ddest[i];
}
}
}
}
/* inflate an uncompressed block of data */
this.inflate_uncompressed_block = function(d)
{
var length, invlength;
var i;
/* 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.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);
this.header = null;
}
/* inflate stream from source to dest */
this.uncompress = function(source, offset)
{
var d = this.d;
var bfinal;
if (Object.prototype.toString.call(source) === '[object Array]') {
source.charCodeAt = function(id) { return this[id]; }
}
/* initialise data */
d.source = source;
d.sourceIndex = offset;
d.bitcount = 0;
d.dest = [];
// Skip zlib header at start of stream
/*if (typeof header == 'undefined') {
header = this.read_bits(d, 16, 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 };
} while (!bfinal);
if (Object.prototype.toString.call(source) !== '[object Array]') {
d.dest = d.dest.join('');
}
return { 'status' : this.OK, 'data' : d.dest };
}
};
Markdown is supported
0% or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment