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Code Issues Releases Wiki Activity

Start on Issue #16. Make BitStream a module, but provide a Web Worker version of BitStream via a build step

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codedread 2020-04-01 23:08:09 -07:00
parent 469a93d6e1
commit a457564ff0
8 changed files with 1043 additions and 427 deletions
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225
archive/unrar.js
View file

@ -12,7 +12,7 @@
// present.
// This file expects to be invoked as a Worker (see onmessage below).
importScripts('../io/bitstream.js');
importScripts('../io/bitstream-worker.js');
importScripts('../io/bytestream.js');
importScripts('../io/bytebuffer.js');
importScripts('archive.js');
@ -40,45 +40,45 @@ let totalUncompressedBytesInArchive = 0;
let totalFilesInArchive = 0;
// Helper functions.
const info = function(str) {
const info = function (str) {
postMessage(new bitjs.archive.UnarchiveInfoEvent(str));
};
const err = function(str) {
const err = function (str) {
postMessage(new bitjs.archive.UnarchiveErrorEvent(str));
};
const postProgress = function() {
const postProgress = function () {
postMessage(new bitjs.archive.UnarchiveProgressEvent(
currentFilename,
currentFileNumber,
currentBytesUnarchivedInFile,
currentBytesUnarchived,
totalUncompressedBytesInArchive,
totalFilesInArchive,
parseInt(bytestream.getNumBytesRead(), 10),
currentFilename,
currentFileNumber,
currentBytesUnarchivedInFile,
currentBytesUnarchived,
totalUncompressedBytesInArchive,
totalFilesInArchive,
parseInt(bytestream.getNumBytesRead(), 10),
));
};
// shows a byte value as its hex representation
const nibble = '0123456789ABCDEF';
const byteValueToHexString = function(num) {
return nibble[num>>4] + nibble[num&0xF];
const byteValueToHexString = function (num) {
return nibble[num >> 4] + nibble[num & 0xF];
};
const twoByteValueToHexString = function(num) {
return nibble[(num>>12)&0xF] + nibble[(num>>8)&0xF] + nibble[(num>>4)&0xF] + nibble[num&0xF];
const twoByteValueToHexString = function (num) {
return nibble[(num >> 12) & 0xF] + nibble[(num >> 8) & 0xF] + nibble[(num >> 4) & 0xF] + nibble[num & 0xF];
};
// Volume Types
const MARK_HEAD = 0x72;
const MAIN_HEAD = 0x73;
const FILE_HEAD = 0x74;
const COMM_HEAD = 0x75;
const AV_HEAD = 0x76;
const SUB_HEAD = 0x77;
const PROTECT_HEAD = 0x78;
const SIGN_HEAD = 0x79;
const NEWSUB_HEAD = 0x7a;
const ENDARC_HEAD = 0x7b;
const MARK_HEAD = 0x72;
const MAIN_HEAD = 0x73;
const FILE_HEAD = 0x74;
const COMM_HEAD = 0x75;
const AV_HEAD = 0x76;
const SUB_HEAD = 0x77;
const PROTECT_HEAD = 0x78;
const SIGN_HEAD = 0x79;
const NEWSUB_HEAD = 0x7a;
const ENDARC_HEAD = 0x7b;
// ============================================================================================== //
@ -102,7 +102,7 @@ class RarVolumeHeader {
this.flags = {};
this.flags.value = bstream.readNumber(2);
const flagsValue = this.flags.value;
switch (this.headType) {
case MAIN_HEAD:
this.flags.MHD_VOLUME = !!(flagsValue & 0x01);
@ -164,7 +164,7 @@ class RarVolumeHeader {
this.nameSize = bstream.readNumber(2);
this.fileAttr = bstream.readNumber(4);
headBytesRead += 25;
if (this.flags.LHD_LARGE) {
//info('Warning: Reading in LHD_LARGE 64-bit size values');
this.HighPackSize = bstream.readNumber(4);
@ -253,8 +253,8 @@ class RarVolumeHeader {
info(' headSize=' + this.headSize);
if (this.headType == FILE_HEAD) {
info('Found FILE_HEAD with packSize=' + this.packSize + ', unpackedSize= ' +
this.unpackedSize + ', hostOS=' + this.hostOS + ', unpVer=' + this.unpVer + ', method=' +
this.method + ', filename=' + this.filename);
this.unpackedSize + ', hostOS=' + this.hostOS + ', unpVer=' + this.unpVer + ', method=' +
this.method + ', filename=' + this.filename);
}
}
}
@ -262,21 +262,21 @@ class RarVolumeHeader {
const BLOCK_LZ = 0;
const BLOCK_PPM = 1;
const rLDecode = [0,1,2,3,4,5,6,7,8,10,12,14,16,20,24,28,32,40,48,56,64,80,96,112,128,160,192,224];
const rLBits = [0,0,0,0,0,0,0,0,1, 1, 1, 1, 2, 2, 2, 2, 3, 3, 3, 3, 4, 4, 4, 4, 5, 5, 5, 5];
const rDBitLengthCounts = [4,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,14,0,12];
const rSDDecode = [0,4,8,16,32,64,128,192];
const rSDBits = [2,2,3, 4, 5, 6, 6, 6];
const rLDecode = [0, 1, 2, 3, 4, 5, 6, 7, 8, 10, 12, 14, 16, 20, 24, 28, 32, 40, 48, 56, 64, 80, 96, 112, 128, 160, 192, 224];
const rLBits = [0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 2, 2, 3, 3, 3, 3, 4, 4, 4, 4, 5, 5, 5, 5];
const rDBitLengthCounts = [4, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 14, 0, 12];
const rSDDecode = [0, 4, 8, 16, 32, 64, 128, 192];
const rSDBits = [2, 2, 3, 4, 5, 6, 6, 6];
const rDDecode = [0, 1, 2, 3, 4, 6, 8, 12, 16, 24, 32,
48, 64, 96, 128, 192, 256, 384, 512, 768, 1024, 1536, 2048, 3072,
4096, 6144, 8192, 12288, 16384, 24576, 32768, 49152, 65536, 98304,
131072, 196608, 262144, 327680, 393216, 458752, 524288, 589824,
655360, 720896, 786432, 851968, 917504, 983040];
48, 64, 96, 128, 192, 256, 384, 512, 768, 1024, 1536, 2048, 3072,
4096, 6144, 8192, 12288, 16384, 24576, 32768, 49152, 65536, 98304,
131072, 196608, 262144, 327680, 393216, 458752, 524288, 589824,
655360, 720896, 786432, 851968, 917504, 983040];
const rDBits = [0, 0, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5,
5, 6, 6, 7, 7, 8, 8, 9, 9, 10, 10, 11, 11, 12, 12, 13, 13, 14, 14,
15, 15, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16];
5, 6, 6, 7, 7, 8, 8, 9, 9, 10, 10, 11, 11, 12, 12, 13, 13, 14, 14,
15, 15, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16];
const rLOW_DIST_REP_COUNT = 16;
@ -285,7 +285,7 @@ const rDC = 60;
const rLDC = 17;
const rRC = 28;
const rBC = 20;
const rHUFF_TABLE_SIZE = (rNC+rDC+rRC+rLDC);
const rHUFF_TABLE_SIZE = (rNC + rDC + rRC + rLDC);
const UnpOldTable = new Array(rHUFF_TABLE_SIZE);
@ -353,13 +353,13 @@ function RarReadTables(bstream) {
const Table = new Array(rHUFF_TABLE_SIZE);
// before we start anything we need to get byte-aligned
bstream.readBits( (8 - bstream.bitPtr) & 0x7 );
bstream.readBits((8 - bstream.bitPtr) & 0x7);
if (bstream.readBits(1)) {
info('Error! PPM not implemented yet');
return;
}
if (!bstream.readBits(1)) { //discard old table
for (let i = UnpOldTable.length; i--;) {
UnpOldTable[i] = 0;
@ -384,11 +384,11 @@ function RarReadTables(bstream) {
BitLength[I] = Length;
}
}
// now all 20 bit lengths are obtained, we construct the Huffman Table:
RarMakeDecodeTables(BitLength, 0, BD, rBC);
const TableSize = rHUFF_TABLE_SIZE;
for (let i = 0; i < TableSize;) {
const num = RarDecodeNumber(bstream, BD);
@ -410,12 +410,12 @@ function RarReadTables(bstream) {
}
}
}
RarMakeDecodeTables(Table, 0, LD, rNC);
RarMakeDecodeTables(Table, rNC, DD, rDC);
RarMakeDecodeTables(Table, rNC + rDC, LDD, rLDC);
RarMakeDecodeTables(Table, rNC + rDC + rLDC, RD, rRC);
RarMakeDecodeTables(Table, rNC + rDC + rLDC, RD, rRC);
for (let i = UnpOldTable.length; i--;) {
UnpOldTable[i] = Table[i];
}
@ -429,24 +429,24 @@ function RarDecodeNumber(bstream, dec) {
const DecodeNum = dec.DecodeNum;
const bitField = bstream.getBits() & 0xfffe;
//some sort of rolled out binary search
const bits = ((bitField < DecodeLen[8])?
((bitField < DecodeLen[4])?
((bitField < DecodeLen[2])?
((bitField < DecodeLen[1])?1:2)
:((bitField < DecodeLen[3])?3:4))
:(bitField < DecodeLen[6])?
((bitField < DecodeLen[5])?5:6)
:((bitField < DecodeLen[7])?7:8))
:((bitField < DecodeLen[12])?
((bitField < DecodeLen[10])?
((bitField < DecodeLen[9])?9:10)
:((bitField < DecodeLen[11])?11:12))
:(bitField < DecodeLen[14])?
((bitField < DecodeLen[13])?13:14)
:15));
const bits = ((bitField < DecodeLen[8]) ?
((bitField < DecodeLen[4]) ?
((bitField < DecodeLen[2]) ?
((bitField < DecodeLen[1]) ? 1 : 2)
: ((bitField < DecodeLen[3]) ? 3 : 4))
: (bitField < DecodeLen[6]) ?
((bitField < DecodeLen[5]) ? 5 : 6)
: ((bitField < DecodeLen[7]) ? 7 : 8))
: ((bitField < DecodeLen[12]) ?
((bitField < DecodeLen[10]) ?
((bitField < DecodeLen[9]) ? 9 : 10)
: ((bitField < DecodeLen[11]) ? 11 : 12))
: (bitField < DecodeLen[14]) ?
((bitField < DecodeLen[13]) ? 13 : 14)
: 15));
bstream.readBits(bits);
const N = DecodePos[bits] + ((bitField - DecodeLen[bits -1]) >>> (16 - bits));
const N = DecodePos[bits] + ((bitField - DecodeLen[bits - 1]) >>> (16 - bits));
return DecodeNum[N];
}
@ -455,8 +455,8 @@ function RarMakeDecodeTables(BitLength, offset, dec, size) {
const DecodeLen = dec.DecodeLen;
const DecodePos = dec.DecodePos;
const DecodeNum = dec.DecodeNum;
const LenCount = [0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0];
const TmpPos = [0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0];
const LenCount = [0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0];
const TmpPos = [0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0];
let N = 0;
let M = 0;
@ -470,20 +470,20 @@ function RarMakeDecodeTables(BitLength, offset, dec, size) {
TmpPos[0] = 0;
DecodePos[0] = 0;
DecodeLen[0] = 0;
for (let I = 1; I < 16; ++I) {
N = 2 * (N+LenCount[I]);
M = (N << (15-I));
N = 2 * (N + LenCount[I]);
M = (N << (15 - I));
if (M > 0xFFFF) {
M = 0xFFFF;
}
DecodeLen[I] = M;
DecodePos[I] = DecodePos[I-1] + LenCount[I-1];
DecodePos[I] = DecodePos[I - 1] + LenCount[I - 1];
TmpPos[I] = DecodePos[I];
}
for (let I = 0; I < size; ++I) {
if (BitLength[I + offset] != 0) {
DecodeNum[ TmpPos[ BitLength[offset + I] & 0xF ]++] = I;
DecodeNum[TmpPos[BitLength[offset + I] & 0xF]++] = I;
}
}
@ -550,7 +550,7 @@ function Unpack20(bstream, Solid) {
if (num < 261) {
const Distance = rOldDist[(oldDistPtr - (num - 256)) & 3];
const LengthNumber = RarDecodeNumber(bstream, RD);
let Length = rLDecode[LengthNumber] +2;
let Length = rLDecode[LengthNumber] + 2;
if ((Bits = rLBits[LengthNumber]) > 0) {
Length += bstream.readBits(Bits);
}
@ -578,7 +578,7 @@ function Unpack20(bstream, Solid) {
RarCopyString(2, Distance);
continue;
}
}
RarUpdateProgress();
}
@ -650,7 +650,7 @@ function RarReadTables20(bstream) {
let lowDistRepCount = 0;
let prevLowDist = 0;
let rOldDist = [0,0,0,0];
let rOldDist = [0, 0, 0, 0];
let lastDist;
let lastLength;
@ -767,11 +767,11 @@ function RarAddVMCode(firstByte, vmCode) {
stackFilter.BlockLength = RarVM.readData(bstream);
} else {
stackFilter.BlockLength = filtPos < OldFilterLengths.length
? OldFilterLengths[filtPos]
: 0;
? OldFilterLengths[filtPos]
: 0;
}
stackFilter.NextWindow = (wBuffer.ptr != rBuffer.ptr) &&
(((wBuffer.ptr - rBuffer.ptr) & MAXWINMASK) <= blockStart);
(((wBuffer.ptr - rBuffer.ptr) & MAXWINMASK) <= blockStart);
OldFilterLengths[filtPos] = stackFilter.BlockLength;
@ -894,36 +894,36 @@ function Unpack29(bstream, Solid) {
const DDecode = new Array(rDC);
const DBits = new Array(rDC);
let Dist = 0;
let BitLength = 0;
let Slot = 0;
for (let I = 0; I < rDBitLengthCounts.length; I++,BitLength++) {
for (let J = 0; J < rDBitLengthCounts[I]; J++,Slot++,Dist+=(1<<BitLength)) {
DDecode[Slot]=Dist;
DBits[Slot]=BitLength;
for (let I = 0; I < rDBitLengthCounts.length; I++, BitLength++) {
for (let J = 0; J < rDBitLengthCounts[I]; J++, Slot++, Dist += (1 << BitLength)) {
DDecode[Slot] = Dist;
DBits[Slot] = BitLength;
}
}
let Bits;
//tablesRead = false;
rOldDist = [0,0,0,0]
rOldDist = [0, 0, 0, 0]
lastDist = 0;
lastLength = 0;
for (let i = UnpOldTable.length; i--;) {
UnpOldTable[i] = 0;
}
// read in Huffman tables
RarReadTables(bstream);
while (true) {
let num = RarDecodeNumber(bstream, LD);
if (num < 256) {
rBuffer.insertByte(num);
continue;
@ -993,7 +993,7 @@ function Unpack29(bstream, Solid) {
const Distance = rOldDist[DistNum];
for (let I = DistNum; I > 0; I--) {
rOldDist[I] = rOldDist[I-1];
rOldDist[I] = rOldDist[I - 1];
}
rOldDist[0] = Distance;
@ -1076,8 +1076,8 @@ function RarWriteBuf() {
parentPrg.GlobalData = new Uint8Array(globalDataLen);
}
parentPrg.GlobalData.set(
this.mem_.subarray(VM_FIXEDGLOBALSIZE, VM_FIXEDGLOBALSIZE + globalDataLen),
VM_FIXEDGLOBALSIZE);
this.mem_.subarray(VM_FIXEDGLOBALSIZE, VM_FIXEDGLOBALSIZE + globalDataLen),
VM_FIXEDGLOBALSIZE);
} else {
parentPrg.GlobalData = new Uint8Array(0);
}
@ -1088,7 +1088,7 @@ function RarWriteBuf() {
while (i + 1 < PrgStack.length) {
const nextFilter = PrgStack[i + 1];
if (nextFilter == null || nextFilter.BlockStart != blockStart ||
nextFilter.BlockLength != filteredData.length || nextFilter.NextWindow) {
nextFilter.BlockLength != filteredData.length || nextFilter.NextWindow) {
break;
}
@ -1115,8 +1115,8 @@ function RarWriteBuf() {
innerParentPrg.GlobalData = new Uint8Array(globalDataLen);
}
innerParentPrg.GlobalData.set(
this.mem_.subarray(VM_FIXEDGLOBALSIZE, VM_FIXEDGLOBALSIZE + globalDataLen),
VM_FIXEDGLOBALSIZE);
this.mem_.subarray(VM_FIXEDGLOBALSIZE, VM_FIXEDGLOBALSIZE + globalDataLen),
VM_FIXEDGLOBALSIZE);
} else {
innerParentPrg.GlobalData = new Uint8Array(0);
}
@ -1158,8 +1158,8 @@ function RarWriteBuf() {
function RarWriteArea(startPtr, endPtr) {
if (endPtr < startPtr) {
console.error('endPtr < startPtr, endPtr=' + endPtr + ', startPtr=' + startPtr);
// RarWriteData(startPtr, -(int)StartPtr & MAXWINMASK);
// RarWriteData(0, endPtr);
// RarWriteData(startPtr, -(int)StartPtr & MAXWINMASK);
// RarWriteData(0, endPtr);
return;
} else if (startPtr < endPtr) {
RarWriteData(startPtr, endPtr - startPtr);
@ -1187,8 +1187,7 @@ function RarWriteData(offset, numBytes) {
/**
* @param {VM_PreparedProgram} prg
*/
function RarExecuteCode(prg)
{
function RarExecuteCode(prg) {
if (prg.GlobalData.length > 0) {
const writtenFileSize = wBuffer.ptr;
prg.InitR[6] = writtenFileSize;
@ -1219,8 +1218,8 @@ function RarInsertLastMatch(length, distance) {
}
function RarInsertOldDist(distance) {
rOldDist.splice(3,1);
rOldDist.splice(0,0,distance);
rOldDist.splice(3, 1);
rOldDist.splice(0, 0, distance);
}
/**
@ -1259,7 +1258,7 @@ function unpack(v) {
// TODO: implement what happens when unpVer is < 15
const Ver = v.header.unpVer <= 15 ? 15 : v.header.unpVer;
const Solid = v.header.flags.LHD_SOLID;
const bstream = new bitjs.io.BitStream(v.fileData.buffer, true /* rtl */, v.fileData.byteOffset, v.fileData.byteLength );
const bstream = new bitjs.io.BitStream(v.fileData.buffer, true /* rtl */, v.fileData.byteOffset, v.fileData.byteLength);
rBuffer = new bitjs.io.ByteBuffer(v.header.unpackedSize);
@ -1296,7 +1295,7 @@ class RarLocalFile {
constructor(bstream) {
this.header = new RarVolumeHeader(bstream);
this.filename = this.header.filename;
if (this.header.headType != FILE_HEAD && this.header.headType != ENDARC_HEAD) {
this.isValid = false;
info('Error! RAR Volume did not include a FILE_HEAD header ');
@ -1340,10 +1339,10 @@ class RarLocalFile {
function unrar_start() {
let bstream = bytestream.tee();
const header = new RarVolumeHeader(bstream);
if (header.crc == 0x6152 &&
header.headType == 0x72 &&
header.flags.value == 0x1A21 &&
header.headSize == 7) {
if (header.crc == 0x6152 &&
header.headType == 0x72 &&
header.flags.value == 0x1A21 &&
header.headSize == 7) {
if (logToConsole) {
info('Found RAR signature');
}
@ -1388,7 +1387,7 @@ function unrar() {
} while (localFile.isValid && bstream.getNumBytesLeft() > 0);
totalFilesInArchive = allLocalFiles.length;
postProgress();
bytestream = bstream.tee();
@ -1396,7 +1395,7 @@ function unrar() {
// event.data.file has the first ArrayBuffer.
// event.data.bytes has all subsequent ArrayBuffers.
onmessage = function(event) {
onmessage = function (event) {
const bytes = event.data.file || event.data.bytes;
logToConsole = !!event.data.logToConsole;
@ -1437,7 +1436,7 @@ onmessage = function(event) {
}
if (unarchiveState === UnarchiveState.UNARCHIVING ||
unarchiveState === UnarchiveState.WAITING) {
unarchiveState === UnarchiveState.WAITING) {
try {
unrar();
unarchiveState = UnarchiveState.FINISHED;

134
archive/unzip.js
View file

@ -13,7 +13,7 @@
*/
// This file expects to be invoked as a Worker (see onmessage below).
importScripts('../io/bitstream.js');
importScripts('../io/bitstream-worker.js');
importScripts('../io/bytebuffer.js');
importScripts('../io/bytestream.js');
importScripts('archive.js');
@ -40,21 +40,21 @@ let totalUncompressedBytesInArchive = 0;
let totalFilesInArchive = 0;
// Helper functions.
const info = function(str) {
const info = function (str) {
postMessage(new bitjs.archive.UnarchiveInfoEvent(str));
};
const err = function(str) {
const err = function (str) {
postMessage(new bitjs.archive.UnarchiveErrorEvent(str));
};
const postProgress = function() {
const postProgress = function () {
postMessage(new bitjs.archive.UnarchiveProgressEvent(
currentFilename,
currentFileNumber,
currentBytesUnarchivedInFile,
currentBytesUnarchived,
totalUncompressedBytesInArchive,
totalFilesInArchive,
bytestream.getNumBytesRead(),
currentFilename,
currentFileNumber,
currentBytesUnarchivedInFile,
currentBytesUnarchived,
totalUncompressedBytesInArchive,
totalFilesInArchive,
bytestream.getNumBytesRead(),
));
};
@ -66,16 +66,16 @@ const zEndOfCentralDirSignature = 0x06054b50;
const zEndOfCentralDirLocatorSignature = 0x07064b50;
// mask for getting the Nth bit (zero-based)
const BIT = [ 0x01, 0x02, 0x04, 0x08,
0x10, 0x20, 0x40, 0x80,
0x100, 0x200, 0x400, 0x800,
0x1000, 0x2000, 0x4000, 0x8000];
const BIT = [0x01, 0x02, 0x04, 0x08,
0x10, 0x20, 0x40, 0x80,
0x100, 0x200, 0x400, 0x800,
0x1000, 0x2000, 0x4000, 0x8000];
class ZipLocalFile {
// takes a ByteStream and parses out the local file information
constructor(bstream) {
if (typeof bstream != typeof {} || !bstream.readNumber || typeof bstream.readNumber != typeof function(){}) {
if (typeof bstream != typeof {} || !bstream.readNumber || typeof bstream.readNumber != typeof function () { }) {
return null;
}
@ -138,9 +138,9 @@ class ZipLocalFile {
// determine what kind of compressed data we have and decompress
unzip() {
// Zip Version 1.0, no compression (store only)
if (this.compressionMethod == 0 ) {
if (this.compressionMethod == 0) {
if (logToConsole) {
info("ZIP v"+this.version+", store only: " + this.filename + " (" + this.compressedSize + " bytes)");
info("ZIP v" + this.version + ", store only: " + this.filename + " (" + this.compressedSize + " bytes)");
}
currentBytesUnarchivedInFile = this.compressedSize;
currentBytesUnarchived += this.compressedSize;
@ -193,10 +193,10 @@ function getHuffmanCodes(bitLengths) {
const next_code = [];
let code = 0;
for (let bits = 1; bits <= MAX_BITS; ++bits) {
const length = bits-1;
const length = bits - 1;
// ensure undefined lengths are zero
if (bl_count[length] == undefined) bl_count[length] = 0;
code = (code + bl_count[bits-1]) << 1;
code = (code + bl_count[bits - 1]) << 1;
next_code[bits] = code;
}
@ -236,18 +236,18 @@ function getHuffmanCodes(bitLengths) {
let fixedHCtoLiteral = null;
let fixedHCtoDistance = null;
function getFixedLiteralTable() {
// create once
if (!fixedHCtoLiteral) {
const bitlengths = new Array(288);
for (let i = 0; i <= 143; ++i) bitlengths[i] = 8;
for (let i = 144; i <= 255; ++i) bitlengths[i] = 9;
for (let i = 256; i <= 279; ++i) bitlengths[i] = 7;
for (let i = 280; i <= 287; ++i) bitlengths[i] = 8;
// create once
if (!fixedHCtoLiteral) {
const bitlengths = new Array(288);
for (let i = 0; i <= 143; ++i) bitlengths[i] = 8;
for (let i = 144; i <= 255; ++i) bitlengths[i] = 9;
for (let i = 256; i <= 279; ++i) bitlengths[i] = 7;
for (let i = 280; i <= 287; ++i) bitlengths[i] = 8;
// get huffman code table
fixedHCtoLiteral = getHuffmanCodes(bitlengths);
}
return fixedHCtoLiteral;
// get huffman code table
fixedHCtoLiteral = getHuffmanCodes(bitlengths);
}
return fixedHCtoLiteral;
}
function getFixedDistanceTable() {
@ -270,10 +270,10 @@ function decodeSymbol(bstream, hcTable) {
let match = false;
// loop until we match
for (;;) {
for (; ;) {
// read in next bit
const bit = bstream.readBits(1);
code = (code<<1) | bit;
code = (code << 1) | bit;
++len;
// check against Huffman Code table and break if found
@ -282,7 +282,7 @@ function decodeSymbol(bstream, hcTable) {
}
if (len > hcTable.maxLength) {
err("Bit stream out of sync, didn't find a Huffman Code, length was " + len +
" and table only max code length of " + hcTable.maxLength);
" and table only max code length of " + hcTable.maxLength);
break;
}
}
@ -308,14 +308,14 @@ Code Bits Length(s) Code Bits Lengths Code Bits Length(s)
266 1 13,14 276 3 59-66
*/
const LengthLookupTable = [
[0,3], [0,4], [0,5], [0,6],
[0,7], [0,8], [0,9], [0,10],
[1,11], [1,13], [1,15], [1,17],
[2,19], [2,23], [2,27], [2,31],
[3,35], [3,43], [3,51], [3,59],
[4,67], [4,83], [4,99], [4,115],
[5,131], [5,163], [5,195], [5,227],
[0,258]
[0, 3], [0, 4], [0, 5], [0, 6],
[0, 7], [0, 8], [0, 9], [0, 10],
[1, 11], [1, 13], [1, 15], [1, 17],
[2, 19], [2, 23], [2, 27], [2, 31],
[3, 35], [3, 43], [3, 51], [3, 59],
[4, 67], [4, 83], [4, 99], [4, 115],
[5, 131], [5, 163], [5, 195], [5, 227],
[0, 258]
];
/*
@ -334,20 +334,20 @@ const LengthLookupTable = [
9 3 25-32 19 8 769-1024 29 13 24577-32768
*/
const DistLookupTable = [
[0,1], [0,2], [0,3], [0,4],
[1,5], [1,7],
[2,9], [2,13],
[3,17], [3,25],
[4,33], [4,49],
[5,65], [5,97],
[6,129], [6,193],
[7,257], [7,385],
[8,513], [8,769],
[9,1025], [9,1537],
[10,2049], [10,3073],
[11,4097], [11,6145],
[12,8193], [12,12289],
[13,16385], [13,24577]
[0, 1], [0, 2], [0, 3], [0, 4],
[1, 5], [1, 7],
[2, 9], [2, 13],
[3, 17], [3, 25],
[4, 33], [4, 49],
[5, 65], [5, 97],
[6, 129], [6, 193],
[7, 257], [7, 385],
[8, 513], [8, 769],
[9, 1025], [9, 1537],
[10, 2049], [10, 3073],
[11, 4097], [11, 6145],
[12, 8193], [12, 12289],
[13, 16385], [13, 24577]
];
function inflateBlockData(bstream, hcLiteralTable, hcDistanceTable, buffer) {
@ -368,7 +368,7 @@ function inflateBlockData(bstream, hcLiteralTable, hcDistanceTable, buffer) {
*/
let numSymbols = 0;
let blockSize = 0;
for (;;) {
for (; ;) {
const symbol = decodeSymbol(bstream, hcLiteralTable);
++numSymbols;
if (symbol < 256) {
@ -398,7 +398,7 @@ function inflateBlockData(bstream, hcLiteralTable, hcDistanceTable, buffer) {
// loop for each character
let ch = buffer.ptr - distance;
blockSize += length;
if(length > distance) {
if (length > distance) {
const data = buffer.data;
while (length--) {
buffer.insertByte(data[ch++]);
@ -418,9 +418,9 @@ function inflateBlockData(bstream, hcLiteralTable, hcDistanceTable, buffer) {
function inflate(compressedData, numDecompressedBytes) {
// Bit stream representing the compressed data.
const bstream = new bitjs.io.BitStream(compressedData.buffer,
false /* rtl */,
compressedData.byteOffset,
compressedData.byteLength);
false /* rtl */,
compressedData.byteOffset,
compressedData.byteLength);
const buffer = new bitjs.io.ByteBuffer(numDecompressedBytes);
let blockSize = 0;
@ -451,9 +451,9 @@ function inflate(compressedData, numDecompressedBytes) {
const numCodeLengthCodes = bstream.readBits(4) + 4;
// populate the array of code length codes (first de-compaction)
const codeLengthsCodeLengths = [0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0];
const codeLengthsCodeLengths = [0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0];
for (let i = 0; i < numCodeLengthCodes; ++i) {
codeLengthsCodeLengths[ CodeLengthCodeOrder[i] ] = bstream.readBits(3);
codeLengthsCodeLengths[CodeLengthCodeOrder[i]] = bstream.readBits(3);
}
// get the Huffman Codes for the code lengths
@ -599,7 +599,7 @@ function unzip() {
cdfh.fileComment = bstream.readString(cdfh.fileCommentLength);
if (logToConsole) {
console.log('Central Directory File Header:');
for (const field in cdfh) {
for (const field in cdfh) {
console.log(` ${field} = ${cdfh[field]}`);
}
}
@ -632,7 +632,7 @@ function unzip() {
eocds.comment = bstream.readString(eocds.commentLength);
if (logToConsole) {
console.log('End of Central Dir Signature:');
for (const field in eocds) {
for (const field in eocds) {
console.log(` ${field} = ${eocds[field]}`);
}
}
@ -649,7 +649,7 @@ function unzip() {
// event.data.file has the first ArrayBuffer.
// event.data.bytes has all subsequent ArrayBuffers.
onmessage = function(event) {
onmessage = function (event) {
const bytes = event.data.file || event.data.bytes;
logToConsole = !!event.data.logToConsole;
@ -678,7 +678,7 @@ onmessage = function(event) {
}
if (unarchiveState === UnarchiveState.UNARCHIVING ||
unarchiveState === UnarchiveState.WAITING) {
unarchiveState === UnarchiveState.WAITING) {
try {
unzip();
} catch (e) {

13
build/Makefile Normal file
View file

@ -0,0 +1,13 @@
all: bitjs-io bitjs-image-webp-shim
clean:
$(MAKE) -C io clean
$(MAKE) -C image/webp-shim clean
bitjs-io:
$(MAKE) -C io
# Make webp-shim/
bitjs-image-webp-shim:
$(MAKE) -C image/webp-shim

25
build/io/Makefile Normal file
View file

@ -0,0 +1,25 @@
OUT_PATH=/out/io
BITSTREAM_MODULE=${OUT_PATH}/bitstream.js
BITSTREAM_WORKER=${OUT_PATH}/bitstream-worker.js
BITSTREAM_DEF=bitstream-def.js
DISCLAIMER="// THIS IS A GENERATED FILE! DO NOT EDIT, INSTEAD EDIT THE FILE IN bitjs/build/io."
all: ${BITSTREAM_MODULE} ${BITSTREAM_WORKER}
${BITSTREAM_MODULE}: Makefile ${BITSTREAM_DEF}
echo ${DISCLAIMER} > ${BITSTREAM_MODULE}
echo "export const BitStream =" >> ${BITSTREAM_MODULE}
cat ${BITSTREAM_DEF} >> ${BITSTREAM_MODULE}
${BITSTREAM_WORKER}: Makefile ${BITSTREAM_DEF}
echo ${DISCLAIMER} > ${BITSTREAM_WORKER}
echo "var bitjs = bitjs || {};" >> ${BITSTREAM_WORKER}
echo "bitjs.io = bitjs.io || {};" >> ${BITSTREAM_WORKER}
echo "bitjs.io.BitStream =" >> ${BITSTREAM_WORKER}
cat ${BITSTREAM_DEF} >> ${BITSTREAM_WORKER}
clean:
rm -rf ${BITSTREAM_MODULE}
rm -rf ${BITSTREAM_WORKER}

287
build/io/bitstream-def.js Normal file
View file

@ -0,0 +1,287 @@
/*
* bitstream-def.js
*
* Provides readers for bitstreams.
*
* Licensed under the MIT License
*
* Copyright(c) 2011 Google Inc.
* Copyright(c) 2011 antimatter15
*/
(function () {
// mask for getting N number of bits (0-8)
const BITMASK = [0, 0x01, 0x03, 0x07, 0x0F, 0x1F, 0x3F, 0x7F, 0xFF];
/**
* This object allows you to peek and consume bits and bytes out of a stream.
* Note that this stream is optimized, and thus, will *NOT* throw an error if
* the end of the stream is reached. Only use this in scenarios where you
* already have all the bits you need.
*/
class BitStream {
/**
* @param {ArrayBuffer} ab An ArrayBuffer object or a Uint8Array.
* @param {boolean} rtl Whether the stream reads bits from the byte starting
* from bit 7 to 0 (true) or bit 0 to 7 (false).
* @param {Number} opt_offset The offset into the ArrayBuffer
* @param {Number} opt_length The length of this BitStream
*/
constructor(ab, rtl, opt_offset, opt_length) {
if (!(ab instanceof ArrayBuffer)) {
throw 'Error! BitArray constructed with an invalid ArrayBuffer object';
}
const offset = opt_offset || 0;
const length = opt_length || ab.byteLength;
/**
* The bytes in the stream.
* @type {Uint8Array}
* @private
*/
this.bytes = new Uint8Array(ab, offset, length);
/**
* The byte in the stream that we are currently on.
* @type {Number}
* @private
*/
this.bytePtr = 0;
/**
* The bit in the current byte that we will read next (can have values 0 through 7).
* @type {Number}
* @private
*/
this.bitPtr = 0; // tracks which bit we are on (can have values 0 through 7)
/**
* An ever-increasing number.
* @type {Number}
* @private
*/
this.bitsRead_ = 0;
this.peekBits = rtl ? this.peekBits_rtl : this.peekBits_ltr;
}
/**
* Returns how many bites have been read in the stream since the beginning of time.
*/
getNumBitsRead() {
return this.bitsRead_;
}
/**
* Returns how many bits are currently in the stream left to be read.
*/
getNumBitsLeft() {
const bitsLeftInByte = 8 - this.bitPtr;
return (this.bytes.byteLength - this.bytePtr - 1) * 8 + bitsLeftInByte;
}
/**
* byte0 byte1 byte2 byte3
* 7......0 | 7......0 | 7......0 | 7......0
*
* The bit pointer starts at bit0 of byte0 and moves left until it reaches
* bit7 of byte0, then jumps to bit0 of byte1, etc.
* @param {number} n The number of bits to peek, must be a positive integer.
* @param {boolean=} movePointers Whether to move the pointer, defaults false.
* @return {number} The peeked bits, as an unsigned number.
*/
peekBits_ltr(n, opt_movePointers) {
const NUM = parseInt(n, 10);
let num = NUM;
if (n !== num || num <= 0) {
return 0;
}
const movePointers = opt_movePointers || false;
let bytes = this.bytes;
let bytePtr = this.bytePtr;
let bitPtr = this.bitPtr;
let result = 0;
let bitsIn = 0;
// keep going until we have no more bits left to peek at
while (num > 0) {
// We overflowed the stream, so just return what we got.
if (bytePtr >= bytes.length) {
break;
}
const numBitsLeftInThisByte = (8 - bitPtr);
if (num >= numBitsLeftInThisByte) {
const mask = (BITMASK[numBitsLeftInThisByte] << bitPtr);
result |= (((bytes[bytePtr] & mask) >> bitPtr) << bitsIn);
bytePtr++;
bitPtr = 0;
bitsIn += numBitsLeftInThisByte;
num -= numBitsLeftInThisByte;
} else {
const mask = (BITMASK[num] << bitPtr);
result |= (((bytes[bytePtr] & mask) >> bitPtr) << bitsIn);
bitPtr += num;
break;
}
}
if (movePointers) {
this.bitPtr = bitPtr;
this.bytePtr = bytePtr;
this.bitsRead_ += NUM;
}
return result;
}
/**
* byte0 byte1 byte2 byte3
* 7......0 | 7......0 | 7......0 | 7......0
*
* The bit pointer starts at bit7 of byte0 and moves right until it reaches
* bit0 of byte0, then goes to bit7 of byte1, etc.
* @param {number} n The number of bits to peek. Must be a positive integer.
* @param {boolean=} movePointers Whether to move the pointer, defaults false.
* @return {number} The peeked bits, as an unsigned number.
*/
peekBits_rtl(n, opt_movePointers) {
const NUM = parseInt(n, 10);
let num = NUM;
if (n !== num || num <= 0) {
return 0;
}
const movePointers = opt_movePointers || false;
let bytes = this.bytes;
let bytePtr = this.bytePtr;
let bitPtr = this.bitPtr;
let result = 0;
// keep going until we have no more bits left to peek at
while (num > 0) {
// We overflowed the stream, so just return the bits we got.
if (bytePtr >= bytes.length) {
break;
}
const numBitsLeftInThisByte = (8 - bitPtr);
if (num >= numBitsLeftInThisByte) {
result <<= numBitsLeftInThisByte;
result |= (BITMASK[numBitsLeftInThisByte] & bytes[bytePtr]);
bytePtr++;
bitPtr = 0;
num -= numBitsLeftInThisByte;
} else {
result <<= num;
const numBits = 8 - num - bitPtr;
result |= ((bytes[bytePtr] & (BITMASK[num] << numBits)) >> numBits);
bitPtr += num;
break;
}
}
if (movePointers) {
this.bitPtr = bitPtr;
this.bytePtr = bytePtr;
this.bitsRead_ += NUM;
}
return result;
}
/**
* Peek at 16 bits from current position in the buffer.
* Bit at (bytePtr,bitPtr) has the highest position in returning data.
* Taken from getbits.hpp in unrar.
* TODO: Move this out of BitStream and into unrar.
*/
getBits() {
return (((((this.bytes[this.bytePtr] & 0xff) << 16) +
((this.bytes[this.bytePtr + 1] & 0xff) << 8) +
((this.bytes[this.bytePtr + 2] & 0xff))) >>> (8 - this.bitPtr)) & 0xffff);
}
/**
* Reads n bits out of the stream, consuming them (moving the bit pointer).
* @param {number} n The number of bits to read. Must be a positive integer.
* @return {number} The read bits, as an unsigned number.
*/
readBits(n) {
return this.peekBits(n, true);
}
/**
* This returns n bytes as a sub-array, advancing the pointer if movePointers
* is true. Only use this for uncompressed blocks as this throws away remaining
* bits in the current byte.
* @param {number} n The number of bytes to peek. Must be a positive integer.
* @param {boolean=} movePointers Whether to move the pointer, defaults false.
* @return {Uint8Array} The subarray.
*/
peekBytes(n, opt_movePointers) {
const num = parseInt(n, 10);
if (n !== num || num < 0) {
throw 'Error! Called peekBytes() with a non-positive integer: ' + n;
} else if (num === 0) {
return new Uint8Array();
}
// Flush bits until we are byte-aligned.
// from http://tools.ietf.org/html/rfc1951#page-11
// "Any bits of input up to the next byte boundary are ignored."
while (this.bitPtr != 0) {
this.readBits(1);
}
const numBytesLeft = this.getNumBitsLeft() / 8;
if (num > numBytesLeft) {
throw 'Error! Overflowed the bit stream! n=' + num + ', bytePtr=' + this.bytePtr +
', bytes.length=' + this.bytes.length + ', bitPtr=' + this.bitPtr;
}
const movePointers = opt_movePointers || false;
const result = new Uint8Array(num);
let bytes = this.bytes;
let ptr = this.bytePtr;
let bytesLeftToCopy = num;
while (bytesLeftToCopy > 0) {
const bytesLeftInStream = bytes.length - ptr;
const sourceLength = Math.min(bytesLeftToCopy, bytesLeftInStream);
result.set(bytes.subarray(ptr, ptr + sourceLength), num - bytesLeftToCopy);
ptr += sourceLength;
// Overflowed the stream, just return what we got.
if (ptr >= bytes.length) {
break;
}
bytesLeftToCopy -= sourceLength;
}
if (movePointers) {
this.bytePtr += num;
this.bitsRead_ += (num * 8);
}
return result;
}
/**
* @param {number} n The number of bytes to read.
* @return {Uint8Array} The subarray.
*/
readBytes(n) {
return this.peekBytes(n, true);
}
}
return BitStream;
})();

291
io/bitstream-worker.js Normal file
View file

@ -0,0 +1,291 @@
// THIS IS A GENERATED FILE! DO NOT EDIT, INSTEAD EDIT THE FILE IN bitjs/build/io.
var bitjs = bitjs || {};
bitjs.io = bitjs.io || {};
bitjs.io.BitStream =
/*
* bitstream-def.js
*
* Provides readers for bitstreams.
*
* Licensed under the MIT License
*
* Copyright(c) 2011 Google Inc.
* Copyright(c) 2011 antimatter15
*/
(function () {
// mask for getting N number of bits (0-8)
const BITMASK = [0, 0x01, 0x03, 0x07, 0x0F, 0x1F, 0x3F, 0x7F, 0xFF];
/**
* This object allows you to peek and consume bits and bytes out of a stream.
* Note that this stream is optimized, and thus, will *NOT* throw an error if
* the end of the stream is reached. Only use this in scenarios where you
* already have all the bits you need.
*/
class BitStream {
/**
* @param {ArrayBuffer} ab An ArrayBuffer object or a Uint8Array.
* @param {boolean} rtl Whether the stream reads bits from the byte starting
* from bit 7 to 0 (true) or bit 0 to 7 (false).
* @param {Number} opt_offset The offset into the ArrayBuffer
* @param {Number} opt_length The length of this BitStream
*/
constructor(ab, rtl, opt_offset, opt_length) {
if (!(ab instanceof ArrayBuffer)) {
throw 'Error! BitArray constructed with an invalid ArrayBuffer object';
}
const offset = opt_offset || 0;
const length = opt_length || ab.byteLength;
/**
* The bytes in the stream.
* @type {Uint8Array}
* @private
*/
this.bytes = new Uint8Array(ab, offset, length);
/**
* The byte in the stream that we are currently on.
* @type {Number}
* @private
*/
this.bytePtr = 0;
/**
* The bit in the current byte that we will read next (can have values 0 through 7).
* @type {Number}
* @private
*/
this.bitPtr = 0; // tracks which bit we are on (can have values 0 through 7)
/**
* An ever-increasing number.
* @type {Number}
* @private
*/
this.bitsRead_ = 0;
this.peekBits = rtl ? this.peekBits_rtl : this.peekBits_ltr;
}
/**
* Returns how many bites have been read in the stream since the beginning of time.
*/
getNumBitsRead() {
return this.bitsRead_;
}
/**
* Returns how many bits are currently in the stream left to be read.
*/
getNumBitsLeft() {
const bitsLeftInByte = 8 - this.bitPtr;
return (this.bytes.byteLength - this.bytePtr - 1) * 8 + bitsLeftInByte;
}
/**
* byte0 byte1 byte2 byte3
* 7......0 | 7......0 | 7......0 | 7......0
*
* The bit pointer starts at bit0 of byte0 and moves left until it reaches
* bit7 of byte0, then jumps to bit0 of byte1, etc.
* @param {number} n The number of bits to peek, must be a positive integer.
* @param {boolean=} movePointers Whether to move the pointer, defaults false.
* @return {number} The peeked bits, as an unsigned number.
*/
peekBits_ltr(n, opt_movePointers) {
const NUM = parseInt(n, 10);
let num = NUM;
if (n !== num || num <= 0) {
return 0;
}
const movePointers = opt_movePointers || false;
let bytes = this.bytes;
let bytePtr = this.bytePtr;
let bitPtr = this.bitPtr;
let result = 0;
let bitsIn = 0;
// keep going until we have no more bits left to peek at
while (num > 0) {
// We overflowed the stream, so just return what we got.
if (bytePtr >= bytes.length) {
break;
}
const numBitsLeftInThisByte = (8 - bitPtr);
if (num >= numBitsLeftInThisByte) {
const mask = (BITMASK[numBitsLeftInThisByte] << bitPtr);
result |= (((bytes[bytePtr] & mask) >> bitPtr) << bitsIn);
bytePtr++;
bitPtr = 0;
bitsIn += numBitsLeftInThisByte;
num -= numBitsLeftInThisByte;
} else {
const mask = (BITMASK[num] << bitPtr);
result |= (((bytes[bytePtr] & mask) >> bitPtr) << bitsIn);
bitPtr += num;
break;
}
}
if (movePointers) {
this.bitPtr = bitPtr;
this.bytePtr = bytePtr;
this.bitsRead_ += NUM;
}
return result;
}
/**
* byte0 byte1 byte2 byte3
* 7......0 | 7......0 | 7......0 | 7......0
*
* The bit pointer starts at bit7 of byte0 and moves right until it reaches
* bit0 of byte0, then goes to bit7 of byte1, etc.
* @param {number} n The number of bits to peek. Must be a positive integer.
* @param {boolean=} movePointers Whether to move the pointer, defaults false.
* @return {number} The peeked bits, as an unsigned number.
*/
peekBits_rtl(n, opt_movePointers) {
const NUM = parseInt(n, 10);
let num = NUM;
if (n !== num || num <= 0) {
return 0;
}
const movePointers = opt_movePointers || false;
let bytes = this.bytes;
let bytePtr = this.bytePtr;
let bitPtr = this.bitPtr;
let result = 0;
// keep going until we have no more bits left to peek at
while (num > 0) {
// We overflowed the stream, so just return the bits we got.
if (bytePtr >= bytes.length) {
break;
}
const numBitsLeftInThisByte = (8 - bitPtr);
if (num >= numBitsLeftInThisByte) {
result <<= numBitsLeftInThisByte;
result |= (BITMASK[numBitsLeftInThisByte] & bytes[bytePtr]);
bytePtr++;
bitPtr = 0;
num -= numBitsLeftInThisByte;
} else {
result <<= num;
const numBits = 8 - num - bitPtr;
result |= ((bytes[bytePtr] & (BITMASK[num] << numBits)) >> numBits);
bitPtr += num;
break;
}
}
if (movePointers) {
this.bitPtr = bitPtr;
this.bytePtr = bytePtr;
this.bitsRead_ += NUM;
}
return result;
}
/**
* Peek at 16 bits from current position in the buffer.
* Bit at (bytePtr,bitPtr) has the highest position in returning data.
* Taken from getbits.hpp in unrar.
* TODO: Move this out of BitStream and into unrar.
*/
getBits() {
return (((((this.bytes[this.bytePtr] & 0xff) << 16) +
((this.bytes[this.bytePtr + 1] & 0xff) << 8) +
((this.bytes[this.bytePtr + 2] & 0xff))) >>> (8 - this.bitPtr)) & 0xffff);
}
/**
* Reads n bits out of the stream, consuming them (moving the bit pointer).
* @param {number} n The number of bits to read. Must be a positive integer.
* @return {number} The read bits, as an unsigned number.
*/
readBits(n) {
return this.peekBits(n, true);
}
/**
* This returns n bytes as a sub-array, advancing the pointer if movePointers
* is true. Only use this for uncompressed blocks as this throws away remaining
* bits in the current byte.
* @param {number} n The number of bytes to peek. Must be a positive integer.
* @param {boolean=} movePointers Whether to move the pointer, defaults false.
* @return {Uint8Array} The subarray.
*/
peekBytes(n, opt_movePointers) {
const num = parseInt(n, 10);
if (n !== num || num < 0) {
throw 'Error! Called peekBytes() with a non-positive integer: ' + n;
} else if (num === 0) {
return new Uint8Array();
}
// Flush bits until we are byte-aligned.
// from http://tools.ietf.org/html/rfc1951#page-11
// "Any bits of input up to the next byte boundary are ignored."
while (this.bitPtr != 0) {
this.readBits(1);
}
const numBytesLeft = this.getNumBitsLeft() / 8;
if (num > numBytesLeft) {
throw 'Error! Overflowed the bit stream! n=' + num + ', bytePtr=' + this.bytePtr +
', bytes.length=' + this.bytes.length + ', bitPtr=' + this.bitPtr;
}
const movePointers = opt_movePointers || false;
const result = new Uint8Array(num);
let bytes = this.bytes;
let ptr = this.bytePtr;
let bytesLeftToCopy = num;
while (bytesLeftToCopy > 0) {
const bytesLeftInStream = bytes.length - ptr;
const sourceLength = Math.min(bytesLeftToCopy, bytesLeftInStream);
result.set(bytes.subarray(ptr, ptr + sourceLength), num - bytesLeftToCopy);
ptr += sourceLength;
// Overflowed the stream, just return what we got.
if (ptr >= bytes.length) {
break;
}
bytesLeftToCopy -= sourceLength;
}
if (movePointers) {
this.bytePtr += num;
this.bitsRead_ += (num * 8);
}
return result;
}
/**
* @param {number} n The number of bytes to read.
* @return {Uint8Array} The subarray.
*/
readBytes(n) {
return this.peekBytes(n, true);
}
}
return BitStream;
})();

493
io/bitstream.js
View file

@ -1,5 +1,7 @@
// THIS IS A GENERATED FILE! DO NOT EDIT, INSTEAD EDIT THE FILE IN bitjs/build/io.
export const BitStream =
/*
* bitstream.js
* bitstream-def.js
*
* Provides readers for bitstreams.
*
@ -9,280 +11,279 @@
* Copyright(c) 2011 antimatter15
*/
var bitjs = bitjs || {};
bitjs.io = bitjs.io || {};
(function () {
// mask for getting N number of bits (0-8)
const BITMASK = [0, 0x01, 0x03, 0x07, 0x0F, 0x1F, 0x3F, 0x7F, 0xFF];
/**
* This object allows you to peek and consume bits and bytes out of a stream.
* Note that this stream is optimized, and thus, will *NOT* throw an error if
* the end of the stream is reached. Only use this in scenarios where you
* already have all the bits you need.
*/
bitjs.io.BitStream = class {
/**
* @param {ArrayBuffer} ab An ArrayBuffer object or a Uint8Array.
* @param {boolean} rtl Whether the stream reads bits from the byte starting
* from bit 7 to 0 (true) or bit 0 to 7 (false).
* @param {Number} opt_offset The offset into the ArrayBuffer
* @param {Number} opt_length The length of this BitStream
* This object allows you to peek and consume bits and bytes out of a stream.
* Note that this stream is optimized, and thus, will *NOT* throw an error if
* the end of the stream is reached. Only use this in scenarios where you
* already have all the bits you need.
*/
constructor(ab, rtl, opt_offset, opt_length) {
if (!(ab instanceof ArrayBuffer)) {
throw 'Error! BitArray constructed with an invalid ArrayBuffer object';
}
class BitStream {
/**
* @param {ArrayBuffer} ab An ArrayBuffer object or a Uint8Array.
* @param {boolean} rtl Whether the stream reads bits from the byte starting
* from bit 7 to 0 (true) or bit 0 to 7 (false).
* @param {Number} opt_offset The offset into the ArrayBuffer
* @param {Number} opt_length The length of this BitStream
*/
constructor(ab, rtl, opt_offset, opt_length) {
if (!(ab instanceof ArrayBuffer)) {
throw 'Error! BitArray constructed with an invalid ArrayBuffer object';
}
const offset = opt_offset || 0;
const length = opt_length || ab.byteLength;
const offset = opt_offset || 0;
const length = opt_length || ab.byteLength;
/**
* The bytes in the stream.
* @type {Uint8Array}
* @private
*/
this.bytes = new Uint8Array(ab, offset, length);
/**
* The byte in the stream that we are currently on.
* @type {Number}
* @private
*/
this.bytePtr = 0;
/**
* The bit in the current byte that we will read next (can have values 0 through 7).
* @type {Number}
* @private
*/
this.bitPtr = 0; // tracks which bit we are on (can have values 0 through 7)
/**
* An ever-increasing number.
* @type {Number}
* @private
*/
this.bitsRead_ = 0;
this.peekBits = rtl ? this.peekBits_rtl : this.peekBits_ltr;
}
/**
* The bytes in the stream.
* @type {Uint8Array}
* @private
* Returns how many bites have been read in the stream since the beginning of time.
*/
this.bytes = new Uint8Array(ab, offset, length);
getNumBitsRead() {
return this.bitsRead_;
}
/**
* The byte in the stream that we are currently on.
* @type {Number}
* @private
* Returns how many bits are currently in the stream left to be read.
*/
this.bytePtr = 0;
getNumBitsLeft() {
const bitsLeftInByte = 8 - this.bitPtr;
return (this.bytes.byteLength - this.bytePtr - 1) * 8 + bitsLeftInByte;
}
/**
* The bit in the current byte that we will read next (can have values 0 through 7).
* @type {Number}
* @private
* byte0 byte1 byte2 byte3
* 7......0 | 7......0 | 7......0 | 7......0
*
* The bit pointer starts at bit0 of byte0 and moves left until it reaches
* bit7 of byte0, then jumps to bit0 of byte1, etc.
* @param {number} n The number of bits to peek, must be a positive integer.
* @param {boolean=} movePointers Whether to move the pointer, defaults false.
* @return {number} The peeked bits, as an unsigned number.
*/
this.bitPtr = 0; // tracks which bit we are on (can have values 0 through 7)
peekBits_ltr(n, opt_movePointers) {
const NUM = parseInt(n, 10);
let num = NUM;
if (n !== num || num <= 0) {
return 0;
}
const movePointers = opt_movePointers || false;
let bytes = this.bytes;
let bytePtr = this.bytePtr;
let bitPtr = this.bitPtr;
let result = 0;
let bitsIn = 0;
// keep going until we have no more bits left to peek at
while (num > 0) {
// We overflowed the stream, so just return what we got.
if (bytePtr >= bytes.length) {
break;
}
const numBitsLeftInThisByte = (8 - bitPtr);
if (num >= numBitsLeftInThisByte) {
const mask = (BITMASK[numBitsLeftInThisByte] << bitPtr);
result |= (((bytes[bytePtr] & mask) >> bitPtr) << bitsIn);
bytePtr++;
bitPtr = 0;
bitsIn += numBitsLeftInThisByte;
num -= numBitsLeftInThisByte;
} else {
const mask = (BITMASK[num] << bitPtr);
result |= (((bytes[bytePtr] & mask) >> bitPtr) << bitsIn);
bitPtr += num;
break;
}
}
if (movePointers) {
this.bitPtr = bitPtr;
this.bytePtr = bytePtr;
this.bitsRead_ += NUM;
}
return result;
}
/**
* An ever-increasing number.
* @type {Number}
* @private
* byte0 byte1 byte2 byte3
* 7......0 | 7......0 | 7......0 | 7......0
*
* The bit pointer starts at bit7 of byte0 and moves right until it reaches
* bit0 of byte0, then goes to bit7 of byte1, etc.
* @param {number} n The number of bits to peek. Must be a positive integer.
* @param {boolean=} movePointers Whether to move the pointer, defaults false.
* @return {number} The peeked bits, as an unsigned number.
*/
this.bitsRead_ = 0;
this.peekBits = rtl ? this.peekBits_rtl : this.peekBits_ltr;
}
/**
* Returns how many bites have been read in the stream since the beginning of time.
*/
getNumBitsRead() {
return this.bitsRead_;
}
/**
* Returns how many bits are currently in the stream left to be read.
*/
getNumBitsLeft() {
const bitsLeftInByte = 8 - this.bitPtr;
return (this.bytes.byteLength - this.bytePtr - 1) * 8 + bitsLeftInByte;
}
/**
* byte0 byte1 byte2 byte3
* 7......0 | 7......0 | 7......0 | 7......0
*
* The bit pointer starts at bit0 of byte0 and moves left until it reaches
* bit7 of byte0, then jumps to bit0 of byte1, etc.
* @param {number} n The number of bits to peek, must be a positive integer.
* @param {boolean=} movePointers Whether to move the pointer, defaults false.
* @return {number} The peeked bits, as an unsigned number.
*/
peekBits_ltr(n, opt_movePointers) {
const NUM = parseInt(n, 10);
let num = NUM;
if (n !== num || num <= 0) {
return 0;
}
const BITMASK = bitjs.io.BitStream.BITMASK;
const movePointers = opt_movePointers || false;
let bytes = this.bytes;
let bytePtr = this.bytePtr;
let bitPtr = this.bitPtr;
let result = 0;
let bitsIn = 0;
// keep going until we have no more bits left to peek at
while (num > 0) {
// We overflowed the stream, so just return what we got.
if (bytePtr >= bytes.length) {
break;
peekBits_rtl(n, opt_movePointers) {
const NUM = parseInt(n, 10);
let num = NUM;
if (n !== num || num <= 0) {
return 0;
}
const numBitsLeftInThisByte = (8 - bitPtr);
if (num >= numBitsLeftInThisByte) {
const mask = (BITMASK[numBitsLeftInThisByte] << bitPtr);
result |= (((bytes[bytePtr] & mask) >> bitPtr) << bitsIn);
const movePointers = opt_movePointers || false;
let bytes = this.bytes;
let bytePtr = this.bytePtr;
let bitPtr = this.bitPtr;
let result = 0;
bytePtr++;
bitPtr = 0;
bitsIn += numBitsLeftInThisByte;
num -= numBitsLeftInThisByte;
} else {
const mask = (BITMASK[num] << bitPtr);
result |= (((bytes[bytePtr] & mask) >> bitPtr) << bitsIn);
// keep going until we have no more bits left to peek at
while (num > 0) {
// We overflowed the stream, so just return the bits we got.
if (bytePtr >= bytes.length) {
break;
}
bitPtr += num;
break;
}
}
const numBitsLeftInThisByte = (8 - bitPtr);
if (num >= numBitsLeftInThisByte) {
result <<= numBitsLeftInThisByte;
result |= (BITMASK[numBitsLeftInThisByte] & bytes[bytePtr]);
bytePtr++;
bitPtr = 0;
num -= numBitsLeftInThisByte;
} else {
result <<= num;
const numBits = 8 - num - bitPtr;
result |= ((bytes[bytePtr] & (BITMASK[num] << numBits)) >> numBits);
if (movePointers) {
this.bitPtr = bitPtr;
this.bytePtr = bytePtr;
this.bitsRead_ += NUM;
}
return result;
}
/**
* byte0 byte1 byte2 byte3
* 7......0 | 7......0 | 7......0 | 7......0
*
* The bit pointer starts at bit7 of byte0 and moves right until it reaches
* bit0 of byte0, then goes to bit7 of byte1, etc.
* @param {number} n The number of bits to peek. Must be a positive integer.
* @param {boolean=} movePointers Whether to move the pointer, defaults false.
* @return {number} The peeked bits, as an unsigned number.
*/
peekBits_rtl(n, opt_movePointers) {
const NUM = parseInt(n, 10);
let num = NUM;
if (n !== num || num <= 0) {
return 0;
}
const BITMASK = bitjs.io.BitStream.BITMASK;
const movePointers = opt_movePointers || false;
let bytes = this.bytes;
let bytePtr = this.bytePtr;
let bitPtr = this.bitPtr;
let result = 0;
// keep going until we have no more bits left to peek at
while (num > 0) {
// We overflowed the stream, so just return the bits we got.
if (bytePtr >= bytes.length) {
break;
bitPtr += num;
break;
}
}
const numBitsLeftInThisByte = (8 - bitPtr);
if (num >= numBitsLeftInThisByte) {
result <<= numBitsLeftInThisByte;
result |= (BITMASK[numBitsLeftInThisByte] & bytes[bytePtr]);
bytePtr++;
bitPtr = 0;
num -= numBitsLeftInThisByte;
} else {
result <<= num;
const numBits = 8 - num - bitPtr;
result |= ((bytes[bytePtr] & (BITMASK[num] << numBits)) >> numBits);
bitPtr += num;
break;
}
}
if (movePointers) {
this.bitPtr = bitPtr;
this.bytePtr = bytePtr;
this.bitsRead_ += NUM;
}
return result;
}
/**
* Peek at 16 bits from current position in the buffer.
* Bit at (bytePtr,bitPtr) has the highest position in returning data.
* Taken from getbits.hpp in unrar.
* TODO: Move this out of BitStream and into unrar.
*/
getBits() {
return (((((this.bytes[this.bytePtr] & 0xff) << 16) +
((this.bytes[this.bytePtr+1] & 0xff) << 8) +
((this.bytes[this.bytePtr+2] & 0xff))) >>> (8-this.bitPtr)) & 0xffff);
}
/**
* Reads n bits out of the stream, consuming them (moving the bit pointer).
* @param {number} n The number of bits to read. Must be a positive integer.
* @return {number} The read bits, as an unsigned number.
*/
readBits(n) {
return this.peekBits(n, true);
}
/**
* This returns n bytes as a sub-array, advancing the pointer if movePointers
* is true. Only use this for uncompressed blocks as this throws away remaining
* bits in the current byte.
* @param {number} n The number of bytes to peek. Must be a positive integer.
* @param {boolean=} movePointers Whether to move the pointer, defaults false.
* @return {Uint8Array} The subarray.
*/
peekBytes(n, opt_movePointers) {
const num = parseInt(n, 10);
if (n !== num || num < 0) {
throw 'Error! Called peekBytes() with a non-positive integer: ' + n;
} else if (num === 0) {
return new Uint8Array();
}
// Flush bits until we are byte-aligned.
// from http://tools.ietf.org/html/rfc1951#page-11
// "Any bits of input up to the next byte boundary are ignored."
while (this.bitPtr != 0) {
this.readBits(1);
}
const numBytesLeft = this.getNumBitsLeft() / 8;
if (num > numBytesLeft) {
throw 'Error! Overflowed the bit stream! n=' + num + ', bytePtr=' + this.bytePtr +
', bytes.length=' + this.bytes.length + ', bitPtr=' + this.bitPtr;
}
const movePointers = opt_movePointers || false;
const result = new Uint8Array(num);
let bytes = this.bytes;
let ptr = this.bytePtr;
let bytesLeftToCopy = num;
while (bytesLeftToCopy > 0) {
const bytesLeftInStream = bytes.length - ptr;
const sourceLength = Math.min(bytesLeftToCopy, bytesLeftInStream);
result.set(bytes.subarray(ptr, ptr + sourceLength), num - bytesLeftToCopy);
ptr += sourceLength;
// Overflowed the stream, just return what we got.
if (ptr >= bytes.length) {
break;
if (movePointers) {
this.bitPtr = bitPtr;
this.bytePtr = bytePtr;
this.bitsRead_ += NUM;
}
bytesLeftToCopy -= sourceLength;
return result;
}
if (movePointers) {
this.bytePtr += num;
this.bitsRead_ += (num * 8);
/**
* Peek at 16 bits from current position in the buffer.
* Bit at (bytePtr,bitPtr) has the highest position in returning data.
* Taken from getbits.hpp in unrar.
* TODO: Move this out of BitStream and into unrar.
*/
getBits() {
return (((((this.bytes[this.bytePtr] & 0xff) << 16) +
((this.bytes[this.bytePtr + 1] & 0xff) << 8) +
((this.bytes[this.bytePtr + 2] & 0xff))) >>> (8 - this.bitPtr)) & 0xffff);
}
return result;
/**
* Reads n bits out of the stream, consuming them (moving the bit pointer).
* @param {number} n The number of bits to read. Must be a positive integer.
* @return {number} The read bits, as an unsigned number.
*/
readBits(n) {
return this.peekBits(n, true);
}
/**
* This returns n bytes as a sub-array, advancing the pointer if movePointers
* is true. Only use this for uncompressed blocks as this throws away remaining
* bits in the current byte.
* @param {number} n The number of bytes to peek. Must be a positive integer.
* @param {boolean=} movePointers Whether to move the pointer, defaults false.
* @return {Uint8Array} The subarray.
*/
peekBytes(n, opt_movePointers) {
const num = parseInt(n, 10);
if (n !== num || num < 0) {
throw 'Error! Called peekBytes() with a non-positive integer: ' + n;
} else if (num === 0) {
return new Uint8Array();
}
// Flush bits until we are byte-aligned.
// from http://tools.ietf.org/html/rfc1951#page-11
// "Any bits of input up to the next byte boundary are ignored."
while (this.bitPtr != 0) {
this.readBits(1);
}
const numBytesLeft = this.getNumBitsLeft() / 8;
if (num > numBytesLeft) {
throw 'Error! Overflowed the bit stream! n=' + num + ', bytePtr=' + this.bytePtr +
', bytes.length=' + this.bytes.length + ', bitPtr=' + this.bitPtr;
}
const movePointers = opt_movePointers || false;
const result = new Uint8Array(num);
let bytes = this.bytes;
let ptr = this.bytePtr;
let bytesLeftToCopy = num;
while (bytesLeftToCopy > 0) {
const bytesLeftInStream = bytes.length - ptr;
const sourceLength = Math.min(bytesLeftToCopy, bytesLeftInStream);
result.set(bytes.subarray(ptr, ptr + sourceLength), num - bytesLeftToCopy);
ptr += sourceLength;
// Overflowed the stream, just return what we got.
if (ptr >= bytes.length) {
break;
}
bytesLeftToCopy -= sourceLength;
}
if (movePointers) {
this.bytePtr += num;
this.bitsRead_ += (num * 8);
}
return result;
}
/**
* @param {number} n The number of bytes to read.
* @return {Uint8Array} The subarray.
*/
readBytes(n) {
return this.peekBytes(n, true);
}
}
/**
* @param {number} n The number of bytes to read.
* @return {Uint8Array} The subarray.
*/
readBytes(n) {
return this.peekBytes(n, true);
}
}
return BitStream;
// mask for getting N number of bits (0-8)
bitjs.io.BitStream.BITMASK = [0, 0x01, 0x03, 0x07, 0x0F, 0x1F, 0x3F, 0x7F, 0xFF ];
})();

2
tests/io-bitstream-test.html
View file

@ -3,7 +3,7 @@
<head>
<title>Unit tests for bitjs.io.BitStream</title>
<script src="muther.js"></script>
<script src="../io/bitstream.js"></script>
<script src="../io/bitstream-worker.js"></script>
</head>
<body>
<script>