From 1e5bf352a5be1d2ba0c689643ca8f397b07611ff Mon Sep 17 00:00:00 2001 From: Jonas Jenwald Date: Tue, 27 Apr 2021 13:49:35 +0200 Subject: [PATCH] Move the `FlateStream` from `src/core/stream.js` and into its own file --- src/core/flate_stream.js | 409 +++++++++++++++++++++++++++++++++++++++ src/core/parser.js | 3 +- src/core/stream.js | 392 +------------------------------------ 3 files changed, 412 insertions(+), 392 deletions(-) create mode 100644 src/core/flate_stream.js diff --git a/src/core/flate_stream.js b/src/core/flate_stream.js new file mode 100644 index 000000000..566aadb92 --- /dev/null +++ b/src/core/flate_stream.js @@ -0,0 +1,409 @@ +/* Copyright 2012 Mozilla Foundation + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ +/* Copyright 1996-2003 Glyph & Cog, LLC + * + * The flate stream implementation contained in this file is a JavaScript port + * of XPDF's implementation, made available under the Apache 2.0 open source + * license. + */ +/* eslint-disable no-var */ + +import { DecodeStream } from "./stream.js"; +import { FormatError } from "../shared/util.js"; + +var FlateStream = (function FlateStreamClosure() { + // prettier-ignore + var codeLenCodeMap = new Int32Array([ + 16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15 + ]); + + // prettier-ignore + var lengthDecode = new Int32Array([ + 0x00003, 0x00004, 0x00005, 0x00006, 0x00007, 0x00008, 0x00009, 0x0000a, + 0x1000b, 0x1000d, 0x1000f, 0x10011, 0x20013, 0x20017, 0x2001b, 0x2001f, + 0x30023, 0x3002b, 0x30033, 0x3003b, 0x40043, 0x40053, 0x40063, 0x40073, + 0x50083, 0x500a3, 0x500c3, 0x500e3, 0x00102, 0x00102, 0x00102 + ]); + + // prettier-ignore + var distDecode = new Int32Array([ + 0x00001, 0x00002, 0x00003, 0x00004, 0x10005, 0x10007, 0x20009, 0x2000d, + 0x30011, 0x30019, 0x40021, 0x40031, 0x50041, 0x50061, 0x60081, 0x600c1, + 0x70101, 0x70181, 0x80201, 0x80301, 0x90401, 0x90601, 0xa0801, 0xa0c01, + 0xb1001, 0xb1801, 0xc2001, 0xc3001, 0xd4001, 0xd6001 + ]); + + // prettier-ignore + var fixedLitCodeTab = [new Int32Array([ + 0x70100, 0x80050, 0x80010, 0x80118, 0x70110, 0x80070, 0x80030, 0x900c0, + 0x70108, 0x80060, 0x80020, 0x900a0, 0x80000, 0x80080, 0x80040, 0x900e0, + 0x70104, 0x80058, 0x80018, 0x90090, 0x70114, 0x80078, 0x80038, 0x900d0, + 0x7010c, 0x80068, 0x80028, 0x900b0, 0x80008, 0x80088, 0x80048, 0x900f0, + 0x70102, 0x80054, 0x80014, 0x8011c, 0x70112, 0x80074, 0x80034, 0x900c8, + 0x7010a, 0x80064, 0x80024, 0x900a8, 0x80004, 0x80084, 0x80044, 0x900e8, + 0x70106, 0x8005c, 0x8001c, 0x90098, 0x70116, 0x8007c, 0x8003c, 0x900d8, + 0x7010e, 0x8006c, 0x8002c, 0x900b8, 0x8000c, 0x8008c, 0x8004c, 0x900f8, + 0x70101, 0x80052, 0x80012, 0x8011a, 0x70111, 0x80072, 0x80032, 0x900c4, + 0x70109, 0x80062, 0x80022, 0x900a4, 0x80002, 0x80082, 0x80042, 0x900e4, + 0x70105, 0x8005a, 0x8001a, 0x90094, 0x70115, 0x8007a, 0x8003a, 0x900d4, + 0x7010d, 0x8006a, 0x8002a, 0x900b4, 0x8000a, 0x8008a, 0x8004a, 0x900f4, + 0x70103, 0x80056, 0x80016, 0x8011e, 0x70113, 0x80076, 0x80036, 0x900cc, + 0x7010b, 0x80066, 0x80026, 0x900ac, 0x80006, 0x80086, 0x80046, 0x900ec, + 0x70107, 0x8005e, 0x8001e, 0x9009c, 0x70117, 0x8007e, 0x8003e, 0x900dc, + 0x7010f, 0x8006e, 0x8002e, 0x900bc, 0x8000e, 0x8008e, 0x8004e, 0x900fc, + 0x70100, 0x80051, 0x80011, 0x80119, 0x70110, 0x80071, 0x80031, 0x900c2, + 0x70108, 0x80061, 0x80021, 0x900a2, 0x80001, 0x80081, 0x80041, 0x900e2, + 0x70104, 0x80059, 0x80019, 0x90092, 0x70114, 0x80079, 0x80039, 0x900d2, + 0x7010c, 0x80069, 0x80029, 0x900b2, 0x80009, 0x80089, 0x80049, 0x900f2, + 0x70102, 0x80055, 0x80015, 0x8011d, 0x70112, 0x80075, 0x80035, 0x900ca, + 0x7010a, 0x80065, 0x80025, 0x900aa, 0x80005, 0x80085, 0x80045, 0x900ea, + 0x70106, 0x8005d, 0x8001d, 0x9009a, 0x70116, 0x8007d, 0x8003d, 0x900da, + 0x7010e, 0x8006d, 0x8002d, 0x900ba, 0x8000d, 0x8008d, 0x8004d, 0x900fa, + 0x70101, 0x80053, 0x80013, 0x8011b, 0x70111, 0x80073, 0x80033, 0x900c6, + 0x70109, 0x80063, 0x80023, 0x900a6, 0x80003, 0x80083, 0x80043, 0x900e6, + 0x70105, 0x8005b, 0x8001b, 0x90096, 0x70115, 0x8007b, 0x8003b, 0x900d6, + 0x7010d, 0x8006b, 0x8002b, 0x900b6, 0x8000b, 0x8008b, 0x8004b, 0x900f6, + 0x70103, 0x80057, 0x80017, 0x8011f, 0x70113, 0x80077, 0x80037, 0x900ce, + 0x7010b, 0x80067, 0x80027, 0x900ae, 0x80007, 0x80087, 0x80047, 0x900ee, + 0x70107, 0x8005f, 0x8001f, 0x9009e, 0x70117, 0x8007f, 0x8003f, 0x900de, + 0x7010f, 0x8006f, 0x8002f, 0x900be, 0x8000f, 0x8008f, 0x8004f, 0x900fe, + 0x70100, 0x80050, 0x80010, 0x80118, 0x70110, 0x80070, 0x80030, 0x900c1, + 0x70108, 0x80060, 0x80020, 0x900a1, 0x80000, 0x80080, 0x80040, 0x900e1, + 0x70104, 0x80058, 0x80018, 0x90091, 0x70114, 0x80078, 0x80038, 0x900d1, + 0x7010c, 0x80068, 0x80028, 0x900b1, 0x80008, 0x80088, 0x80048, 0x900f1, + 0x70102, 0x80054, 0x80014, 0x8011c, 0x70112, 0x80074, 0x80034, 0x900c9, + 0x7010a, 0x80064, 0x80024, 0x900a9, 0x80004, 0x80084, 0x80044, 0x900e9, + 0x70106, 0x8005c, 0x8001c, 0x90099, 0x70116, 0x8007c, 0x8003c, 0x900d9, + 0x7010e, 0x8006c, 0x8002c, 0x900b9, 0x8000c, 0x8008c, 0x8004c, 0x900f9, + 0x70101, 0x80052, 0x80012, 0x8011a, 0x70111, 0x80072, 0x80032, 0x900c5, + 0x70109, 0x80062, 0x80022, 0x900a5, 0x80002, 0x80082, 0x80042, 0x900e5, + 0x70105, 0x8005a, 0x8001a, 0x90095, 0x70115, 0x8007a, 0x8003a, 0x900d5, + 0x7010d, 0x8006a, 0x8002a, 0x900b5, 0x8000a, 0x8008a, 0x8004a, 0x900f5, + 0x70103, 0x80056, 0x80016, 0x8011e, 0x70113, 0x80076, 0x80036, 0x900cd, + 0x7010b, 0x80066, 0x80026, 0x900ad, 0x80006, 0x80086, 0x80046, 0x900ed, + 0x70107, 0x8005e, 0x8001e, 0x9009d, 0x70117, 0x8007e, 0x8003e, 0x900dd, + 0x7010f, 0x8006e, 0x8002e, 0x900bd, 0x8000e, 0x8008e, 0x8004e, 0x900fd, + 0x70100, 0x80051, 0x80011, 0x80119, 0x70110, 0x80071, 0x80031, 0x900c3, + 0x70108, 0x80061, 0x80021, 0x900a3, 0x80001, 0x80081, 0x80041, 0x900e3, + 0x70104, 0x80059, 0x80019, 0x90093, 0x70114, 0x80079, 0x80039, 0x900d3, + 0x7010c, 0x80069, 0x80029, 0x900b3, 0x80009, 0x80089, 0x80049, 0x900f3, + 0x70102, 0x80055, 0x80015, 0x8011d, 0x70112, 0x80075, 0x80035, 0x900cb, + 0x7010a, 0x80065, 0x80025, 0x900ab, 0x80005, 0x80085, 0x80045, 0x900eb, + 0x70106, 0x8005d, 0x8001d, 0x9009b, 0x70116, 0x8007d, 0x8003d, 0x900db, + 0x7010e, 0x8006d, 0x8002d, 0x900bb, 0x8000d, 0x8008d, 0x8004d, 0x900fb, + 0x70101, 0x80053, 0x80013, 0x8011b, 0x70111, 0x80073, 0x80033, 0x900c7, + 0x70109, 0x80063, 0x80023, 0x900a7, 0x80003, 0x80083, 0x80043, 0x900e7, + 0x70105, 0x8005b, 0x8001b, 0x90097, 0x70115, 0x8007b, 0x8003b, 0x900d7, + 0x7010d, 0x8006b, 0x8002b, 0x900b7, 0x8000b, 0x8008b, 0x8004b, 0x900f7, + 0x70103, 0x80057, 0x80017, 0x8011f, 0x70113, 0x80077, 0x80037, 0x900cf, + 0x7010b, 0x80067, 0x80027, 0x900af, 0x80007, 0x80087, 0x80047, 0x900ef, + 0x70107, 0x8005f, 0x8001f, 0x9009f, 0x70117, 0x8007f, 0x8003f, 0x900df, + 0x7010f, 0x8006f, 0x8002f, 0x900bf, 0x8000f, 0x8008f, 0x8004f, 0x900ff + ]), 9]; + + // prettier-ignore + var fixedDistCodeTab = [new Int32Array([ + 0x50000, 0x50010, 0x50008, 0x50018, 0x50004, 0x50014, 0x5000c, 0x5001c, + 0x50002, 0x50012, 0x5000a, 0x5001a, 0x50006, 0x50016, 0x5000e, 0x00000, + 0x50001, 0x50011, 0x50009, 0x50019, 0x50005, 0x50015, 0x5000d, 0x5001d, + 0x50003, 0x50013, 0x5000b, 0x5001b, 0x50007, 0x50017, 0x5000f, 0x00000 + ]), 5]; + + // eslint-disable-next-line no-shadow + function FlateStream(str, maybeLength) { + this.str = str; + this.dict = str.dict; + + var cmf = str.getByte(); + var flg = str.getByte(); + if (cmf === -1 || flg === -1) { + throw new FormatError(`Invalid header in flate stream: ${cmf}, ${flg}`); + } + if ((cmf & 0x0f) !== 0x08) { + throw new FormatError( + `Unknown compression method in flate stream: ${cmf}, ${flg}` + ); + } + if (((cmf << 8) + flg) % 31 !== 0) { + throw new FormatError(`Bad FCHECK in flate stream: ${cmf}, ${flg}`); + } + if (flg & 0x20) { + throw new FormatError(`FDICT bit set in flate stream: ${cmf}, ${flg}`); + } + + this.codeSize = 0; + this.codeBuf = 0; + + DecodeStream.call(this, maybeLength); + } + + FlateStream.prototype = Object.create(DecodeStream.prototype); + + FlateStream.prototype.getBits = function FlateStream_getBits(bits) { + var str = this.str; + var codeSize = this.codeSize; + var codeBuf = this.codeBuf; + + var b; + while (codeSize < bits) { + if ((b = str.getByte()) === -1) { + throw new FormatError("Bad encoding in flate stream"); + } + codeBuf |= b << codeSize; + codeSize += 8; + } + b = codeBuf & ((1 << bits) - 1); + this.codeBuf = codeBuf >> bits; + this.codeSize = codeSize -= bits; + + return b; + }; + + FlateStream.prototype.getCode = function FlateStream_getCode(table) { + var str = this.str; + var codes = table[0]; + var maxLen = table[1]; + var codeSize = this.codeSize; + var codeBuf = this.codeBuf; + + var b; + while (codeSize < maxLen) { + if ((b = str.getByte()) === -1) { + // premature end of stream. code might however still be valid. + // codeSize < codeLen check below guards against incomplete codeVal. + break; + } + codeBuf |= b << codeSize; + codeSize += 8; + } + var code = codes[codeBuf & ((1 << maxLen) - 1)]; + var codeLen = code >> 16; + var codeVal = code & 0xffff; + if (codeLen < 1 || codeSize < codeLen) { + throw new FormatError("Bad encoding in flate stream"); + } + this.codeBuf = codeBuf >> codeLen; + this.codeSize = codeSize - codeLen; + return codeVal; + }; + + FlateStream.prototype.generateHuffmanTable = function flateStreamGenerateHuffmanTable( + lengths + ) { + var n = lengths.length; + + // find max code length + var maxLen = 0; + var i; + for (i = 0; i < n; ++i) { + if (lengths[i] > maxLen) { + maxLen = lengths[i]; + } + } + + // build the table + var size = 1 << maxLen; + var codes = new Int32Array(size); + for ( + var len = 1, code = 0, skip = 2; + len <= maxLen; + ++len, code <<= 1, skip <<= 1 + ) { + for (var val = 0; val < n; ++val) { + if (lengths[val] === len) { + // bit-reverse the code + var code2 = 0; + var t = code; + for (i = 0; i < len; ++i) { + code2 = (code2 << 1) | (t & 1); + t >>= 1; + } + + // fill the table entries + for (i = code2; i < size; i += skip) { + codes[i] = (len << 16) | val; + } + ++code; + } + } + } + + return [codes, maxLen]; + }; + + FlateStream.prototype.readBlock = function FlateStream_readBlock() { + var buffer, len; + var str = this.str; + // read block header + var hdr = this.getBits(3); + if (hdr & 1) { + this.eof = true; + } + hdr >>= 1; + + if (hdr === 0) { + // uncompressed block + var b; + + if ((b = str.getByte()) === -1) { + throw new FormatError("Bad block header in flate stream"); + } + var blockLen = b; + if ((b = str.getByte()) === -1) { + throw new FormatError("Bad block header in flate stream"); + } + blockLen |= b << 8; + if ((b = str.getByte()) === -1) { + throw new FormatError("Bad block header in flate stream"); + } + var check = b; + if ((b = str.getByte()) === -1) { + throw new FormatError("Bad block header in flate stream"); + } + check |= b << 8; + if (check !== (~blockLen & 0xffff) && (blockLen !== 0 || check !== 0)) { + // Ignoring error for bad "empty" block (see issue 1277) + throw new FormatError("Bad uncompressed block length in flate stream"); + } + + this.codeBuf = 0; + this.codeSize = 0; + + const bufferLength = this.bufferLength, + end = bufferLength + blockLen; + buffer = this.ensureBuffer(end); + this.bufferLength = end; + + if (blockLen === 0) { + if (str.peekByte() === -1) { + this.eof = true; + } + } else { + const block = str.getBytes(blockLen); + buffer.set(block, bufferLength); + if (block.length < blockLen) { + this.eof = true; + } + } + return; + } + + var litCodeTable; + var distCodeTable; + if (hdr === 1) { + // compressed block, fixed codes + litCodeTable = fixedLitCodeTab; + distCodeTable = fixedDistCodeTab; + } else if (hdr === 2) { + // compressed block, dynamic codes + var numLitCodes = this.getBits(5) + 257; + var numDistCodes = this.getBits(5) + 1; + var numCodeLenCodes = this.getBits(4) + 4; + + // build the code lengths code table + var codeLenCodeLengths = new Uint8Array(codeLenCodeMap.length); + + var i; + for (i = 0; i < numCodeLenCodes; ++i) { + codeLenCodeLengths[codeLenCodeMap[i]] = this.getBits(3); + } + var codeLenCodeTab = this.generateHuffmanTable(codeLenCodeLengths); + + // build the literal and distance code tables + len = 0; + i = 0; + var codes = numLitCodes + numDistCodes; + var codeLengths = new Uint8Array(codes); + var bitsLength, bitsOffset, what; + while (i < codes) { + var code = this.getCode(codeLenCodeTab); + if (code === 16) { + bitsLength = 2; + bitsOffset = 3; + what = len; + } else if (code === 17) { + bitsLength = 3; + bitsOffset = 3; + what = len = 0; + } else if (code === 18) { + bitsLength = 7; + bitsOffset = 11; + what = len = 0; + } else { + codeLengths[i++] = len = code; + continue; + } + + var repeatLength = this.getBits(bitsLength) + bitsOffset; + while (repeatLength-- > 0) { + codeLengths[i++] = what; + } + } + + litCodeTable = this.generateHuffmanTable( + codeLengths.subarray(0, numLitCodes) + ); + distCodeTable = this.generateHuffmanTable( + codeLengths.subarray(numLitCodes, codes) + ); + } else { + throw new FormatError("Unknown block type in flate stream"); + } + + buffer = this.buffer; + var limit = buffer ? buffer.length : 0; + var pos = this.bufferLength; + while (true) { + var code1 = this.getCode(litCodeTable); + if (code1 < 256) { + if (pos + 1 >= limit) { + buffer = this.ensureBuffer(pos + 1); + limit = buffer.length; + } + buffer[pos++] = code1; + continue; + } + if (code1 === 256) { + this.bufferLength = pos; + return; + } + code1 -= 257; + code1 = lengthDecode[code1]; + var code2 = code1 >> 16; + if (code2 > 0) { + code2 = this.getBits(code2); + } + len = (code1 & 0xffff) + code2; + code1 = this.getCode(distCodeTable); + code1 = distDecode[code1]; + code2 = code1 >> 16; + if (code2 > 0) { + code2 = this.getBits(code2); + } + var dist = (code1 & 0xffff) + code2; + if (pos + len >= limit) { + buffer = this.ensureBuffer(pos + len); + limit = buffer.length; + } + for (var k = 0; k < len; ++k, ++pos) { + buffer[pos] = buffer[pos - dist]; + } + } + }; + + return FlateStream; +})(); + +export { FlateStream }; diff --git a/src/core/parser.js b/src/core/parser.js index bae33d178..24b5cabf5 100644 --- a/src/core/parser.js +++ b/src/core/parser.js @@ -33,15 +33,16 @@ import { Name, Ref, } from "./primitives.js"; -import { FlateStream, NullStream } from "./stream.js"; import { isWhiteSpace, MissingDataException } from "./core_utils.js"; import { Ascii85Stream } from "./ascii_85_stream.js"; import { AsciiHexStream } from "./ascii_hex_stream.js"; import { CCITTFaxStream } from "./ccitt_stream.js"; +import { FlateStream } from "./flate_stream.js"; import { Jbig2Stream } from "./jbig2_stream.js"; import { JpegStream } from "./jpeg_stream.js"; import { JpxStream } from "./jpx_stream.js"; import { LZWStream } from "./lzw_stream.js"; +import { NullStream } from "./stream.js"; import { PredictorStream } from "./predictor_stream.js"; import { RunLengthStream } from "./run_length_stream.js"; diff --git a/src/core/stream.js b/src/core/stream.js index 7f1195ad0..64e71d5a5 100644 --- a/src/core/stream.js +++ b/src/core/stream.js @@ -12,15 +12,9 @@ * See the License for the specific language governing permissions and * limitations under the License. */ -/* Copyright 1996-2003 Glyph & Cog, LLC - * - * The flate stream implementation contained in this file is a JavaScript port - * of XPDF's implementation, made available under the Apache 2.0 open source - * license. - */ /* eslint-disable no-var */ -import { FormatError, stringToBytes, unreachable } from "../shared/util.js"; +import { stringToBytes, unreachable } from "../shared/util.js"; var Stream = (function StreamClosure() { // eslint-disable-next-line no-shadow @@ -342,389 +336,6 @@ var StreamsSequenceStream = (function StreamsSequenceStreamClosure() { return StreamsSequenceStream; })(); -var FlateStream = (function FlateStreamClosure() { - // prettier-ignore - var codeLenCodeMap = new Int32Array([ - 16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15 - ]); - - // prettier-ignore - var lengthDecode = new Int32Array([ - 0x00003, 0x00004, 0x00005, 0x00006, 0x00007, 0x00008, 0x00009, 0x0000a, - 0x1000b, 0x1000d, 0x1000f, 0x10011, 0x20013, 0x20017, 0x2001b, 0x2001f, - 0x30023, 0x3002b, 0x30033, 0x3003b, 0x40043, 0x40053, 0x40063, 0x40073, - 0x50083, 0x500a3, 0x500c3, 0x500e3, 0x00102, 0x00102, 0x00102 - ]); - - // prettier-ignore - var distDecode = new Int32Array([ - 0x00001, 0x00002, 0x00003, 0x00004, 0x10005, 0x10007, 0x20009, 0x2000d, - 0x30011, 0x30019, 0x40021, 0x40031, 0x50041, 0x50061, 0x60081, 0x600c1, - 0x70101, 0x70181, 0x80201, 0x80301, 0x90401, 0x90601, 0xa0801, 0xa0c01, - 0xb1001, 0xb1801, 0xc2001, 0xc3001, 0xd4001, 0xd6001 - ]); - - // prettier-ignore - var fixedLitCodeTab = [new Int32Array([ - 0x70100, 0x80050, 0x80010, 0x80118, 0x70110, 0x80070, 0x80030, 0x900c0, - 0x70108, 0x80060, 0x80020, 0x900a0, 0x80000, 0x80080, 0x80040, 0x900e0, - 0x70104, 0x80058, 0x80018, 0x90090, 0x70114, 0x80078, 0x80038, 0x900d0, - 0x7010c, 0x80068, 0x80028, 0x900b0, 0x80008, 0x80088, 0x80048, 0x900f0, - 0x70102, 0x80054, 0x80014, 0x8011c, 0x70112, 0x80074, 0x80034, 0x900c8, - 0x7010a, 0x80064, 0x80024, 0x900a8, 0x80004, 0x80084, 0x80044, 0x900e8, - 0x70106, 0x8005c, 0x8001c, 0x90098, 0x70116, 0x8007c, 0x8003c, 0x900d8, - 0x7010e, 0x8006c, 0x8002c, 0x900b8, 0x8000c, 0x8008c, 0x8004c, 0x900f8, - 0x70101, 0x80052, 0x80012, 0x8011a, 0x70111, 0x80072, 0x80032, 0x900c4, - 0x70109, 0x80062, 0x80022, 0x900a4, 0x80002, 0x80082, 0x80042, 0x900e4, - 0x70105, 0x8005a, 0x8001a, 0x90094, 0x70115, 0x8007a, 0x8003a, 0x900d4, - 0x7010d, 0x8006a, 0x8002a, 0x900b4, 0x8000a, 0x8008a, 0x8004a, 0x900f4, - 0x70103, 0x80056, 0x80016, 0x8011e, 0x70113, 0x80076, 0x80036, 0x900cc, - 0x7010b, 0x80066, 0x80026, 0x900ac, 0x80006, 0x80086, 0x80046, 0x900ec, - 0x70107, 0x8005e, 0x8001e, 0x9009c, 0x70117, 0x8007e, 0x8003e, 0x900dc, - 0x7010f, 0x8006e, 0x8002e, 0x900bc, 0x8000e, 0x8008e, 0x8004e, 0x900fc, - 0x70100, 0x80051, 0x80011, 0x80119, 0x70110, 0x80071, 0x80031, 0x900c2, - 0x70108, 0x80061, 0x80021, 0x900a2, 0x80001, 0x80081, 0x80041, 0x900e2, - 0x70104, 0x80059, 0x80019, 0x90092, 0x70114, 0x80079, 0x80039, 0x900d2, - 0x7010c, 0x80069, 0x80029, 0x900b2, 0x80009, 0x80089, 0x80049, 0x900f2, - 0x70102, 0x80055, 0x80015, 0x8011d, 0x70112, 0x80075, 0x80035, 0x900ca, - 0x7010a, 0x80065, 0x80025, 0x900aa, 0x80005, 0x80085, 0x80045, 0x900ea, - 0x70106, 0x8005d, 0x8001d, 0x9009a, 0x70116, 0x8007d, 0x8003d, 0x900da, - 0x7010e, 0x8006d, 0x8002d, 0x900ba, 0x8000d, 0x8008d, 0x8004d, 0x900fa, - 0x70101, 0x80053, 0x80013, 0x8011b, 0x70111, 0x80073, 0x80033, 0x900c6, - 0x70109, 0x80063, 0x80023, 0x900a6, 0x80003, 0x80083, 0x80043, 0x900e6, - 0x70105, 0x8005b, 0x8001b, 0x90096, 0x70115, 0x8007b, 0x8003b, 0x900d6, - 0x7010d, 0x8006b, 0x8002b, 0x900b6, 0x8000b, 0x8008b, 0x8004b, 0x900f6, - 0x70103, 0x80057, 0x80017, 0x8011f, 0x70113, 0x80077, 0x80037, 0x900ce, - 0x7010b, 0x80067, 0x80027, 0x900ae, 0x80007, 0x80087, 0x80047, 0x900ee, - 0x70107, 0x8005f, 0x8001f, 0x9009e, 0x70117, 0x8007f, 0x8003f, 0x900de, - 0x7010f, 0x8006f, 0x8002f, 0x900be, 0x8000f, 0x8008f, 0x8004f, 0x900fe, - 0x70100, 0x80050, 0x80010, 0x80118, 0x70110, 0x80070, 0x80030, 0x900c1, - 0x70108, 0x80060, 0x80020, 0x900a1, 0x80000, 0x80080, 0x80040, 0x900e1, - 0x70104, 0x80058, 0x80018, 0x90091, 0x70114, 0x80078, 0x80038, 0x900d1, - 0x7010c, 0x80068, 0x80028, 0x900b1, 0x80008, 0x80088, 0x80048, 0x900f1, - 0x70102, 0x80054, 0x80014, 0x8011c, 0x70112, 0x80074, 0x80034, 0x900c9, - 0x7010a, 0x80064, 0x80024, 0x900a9, 0x80004, 0x80084, 0x80044, 0x900e9, - 0x70106, 0x8005c, 0x8001c, 0x90099, 0x70116, 0x8007c, 0x8003c, 0x900d9, - 0x7010e, 0x8006c, 0x8002c, 0x900b9, 0x8000c, 0x8008c, 0x8004c, 0x900f9, - 0x70101, 0x80052, 0x80012, 0x8011a, 0x70111, 0x80072, 0x80032, 0x900c5, - 0x70109, 0x80062, 0x80022, 0x900a5, 0x80002, 0x80082, 0x80042, 0x900e5, - 0x70105, 0x8005a, 0x8001a, 0x90095, 0x70115, 0x8007a, 0x8003a, 0x900d5, - 0x7010d, 0x8006a, 0x8002a, 0x900b5, 0x8000a, 0x8008a, 0x8004a, 0x900f5, - 0x70103, 0x80056, 0x80016, 0x8011e, 0x70113, 0x80076, 0x80036, 0x900cd, - 0x7010b, 0x80066, 0x80026, 0x900ad, 0x80006, 0x80086, 0x80046, 0x900ed, - 0x70107, 0x8005e, 0x8001e, 0x9009d, 0x70117, 0x8007e, 0x8003e, 0x900dd, - 0x7010f, 0x8006e, 0x8002e, 0x900bd, 0x8000e, 0x8008e, 0x8004e, 0x900fd, - 0x70100, 0x80051, 0x80011, 0x80119, 0x70110, 0x80071, 0x80031, 0x900c3, - 0x70108, 0x80061, 0x80021, 0x900a3, 0x80001, 0x80081, 0x80041, 0x900e3, - 0x70104, 0x80059, 0x80019, 0x90093, 0x70114, 0x80079, 0x80039, 0x900d3, - 0x7010c, 0x80069, 0x80029, 0x900b3, 0x80009, 0x80089, 0x80049, 0x900f3, - 0x70102, 0x80055, 0x80015, 0x8011d, 0x70112, 0x80075, 0x80035, 0x900cb, - 0x7010a, 0x80065, 0x80025, 0x900ab, 0x80005, 0x80085, 0x80045, 0x900eb, - 0x70106, 0x8005d, 0x8001d, 0x9009b, 0x70116, 0x8007d, 0x8003d, 0x900db, - 0x7010e, 0x8006d, 0x8002d, 0x900bb, 0x8000d, 0x8008d, 0x8004d, 0x900fb, - 0x70101, 0x80053, 0x80013, 0x8011b, 0x70111, 0x80073, 0x80033, 0x900c7, - 0x70109, 0x80063, 0x80023, 0x900a7, 0x80003, 0x80083, 0x80043, 0x900e7, - 0x70105, 0x8005b, 0x8001b, 0x90097, 0x70115, 0x8007b, 0x8003b, 0x900d7, - 0x7010d, 0x8006b, 0x8002b, 0x900b7, 0x8000b, 0x8008b, 0x8004b, 0x900f7, - 0x70103, 0x80057, 0x80017, 0x8011f, 0x70113, 0x80077, 0x80037, 0x900cf, - 0x7010b, 0x80067, 0x80027, 0x900af, 0x80007, 0x80087, 0x80047, 0x900ef, - 0x70107, 0x8005f, 0x8001f, 0x9009f, 0x70117, 0x8007f, 0x8003f, 0x900df, - 0x7010f, 0x8006f, 0x8002f, 0x900bf, 0x8000f, 0x8008f, 0x8004f, 0x900ff - ]), 9]; - - // prettier-ignore - var fixedDistCodeTab = [new Int32Array([ - 0x50000, 0x50010, 0x50008, 0x50018, 0x50004, 0x50014, 0x5000c, 0x5001c, - 0x50002, 0x50012, 0x5000a, 0x5001a, 0x50006, 0x50016, 0x5000e, 0x00000, - 0x50001, 0x50011, 0x50009, 0x50019, 0x50005, 0x50015, 0x5000d, 0x5001d, - 0x50003, 0x50013, 0x5000b, 0x5001b, 0x50007, 0x50017, 0x5000f, 0x00000 - ]), 5]; - - // eslint-disable-next-line no-shadow - function FlateStream(str, maybeLength) { - this.str = str; - this.dict = str.dict; - - var cmf = str.getByte(); - var flg = str.getByte(); - if (cmf === -1 || flg === -1) { - throw new FormatError(`Invalid header in flate stream: ${cmf}, ${flg}`); - } - if ((cmf & 0x0f) !== 0x08) { - throw new FormatError( - `Unknown compression method in flate stream: ${cmf}, ${flg}` - ); - } - if (((cmf << 8) + flg) % 31 !== 0) { - throw new FormatError(`Bad FCHECK in flate stream: ${cmf}, ${flg}`); - } - if (flg & 0x20) { - throw new FormatError(`FDICT bit set in flate stream: ${cmf}, ${flg}`); - } - - this.codeSize = 0; - this.codeBuf = 0; - - DecodeStream.call(this, maybeLength); - } - - FlateStream.prototype = Object.create(DecodeStream.prototype); - - FlateStream.prototype.getBits = function FlateStream_getBits(bits) { - var str = this.str; - var codeSize = this.codeSize; - var codeBuf = this.codeBuf; - - var b; - while (codeSize < bits) { - if ((b = str.getByte()) === -1) { - throw new FormatError("Bad encoding in flate stream"); - } - codeBuf |= b << codeSize; - codeSize += 8; - } - b = codeBuf & ((1 << bits) - 1); - this.codeBuf = codeBuf >> bits; - this.codeSize = codeSize -= bits; - - return b; - }; - - FlateStream.prototype.getCode = function FlateStream_getCode(table) { - var str = this.str; - var codes = table[0]; - var maxLen = table[1]; - var codeSize = this.codeSize; - var codeBuf = this.codeBuf; - - var b; - while (codeSize < maxLen) { - if ((b = str.getByte()) === -1) { - // premature end of stream. code might however still be valid. - // codeSize < codeLen check below guards against incomplete codeVal. - break; - } - codeBuf |= b << codeSize; - codeSize += 8; - } - var code = codes[codeBuf & ((1 << maxLen) - 1)]; - var codeLen = code >> 16; - var codeVal = code & 0xffff; - if (codeLen < 1 || codeSize < codeLen) { - throw new FormatError("Bad encoding in flate stream"); - } - this.codeBuf = codeBuf >> codeLen; - this.codeSize = codeSize - codeLen; - return codeVal; - }; - - FlateStream.prototype.generateHuffmanTable = function flateStreamGenerateHuffmanTable( - lengths - ) { - var n = lengths.length; - - // find max code length - var maxLen = 0; - var i; - for (i = 0; i < n; ++i) { - if (lengths[i] > maxLen) { - maxLen = lengths[i]; - } - } - - // build the table - var size = 1 << maxLen; - var codes = new Int32Array(size); - for ( - var len = 1, code = 0, skip = 2; - len <= maxLen; - ++len, code <<= 1, skip <<= 1 - ) { - for (var val = 0; val < n; ++val) { - if (lengths[val] === len) { - // bit-reverse the code - var code2 = 0; - var t = code; - for (i = 0; i < len; ++i) { - code2 = (code2 << 1) | (t & 1); - t >>= 1; - } - - // fill the table entries - for (i = code2; i < size; i += skip) { - codes[i] = (len << 16) | val; - } - ++code; - } - } - } - - return [codes, maxLen]; - }; - - FlateStream.prototype.readBlock = function FlateStream_readBlock() { - var buffer, len; - var str = this.str; - // read block header - var hdr = this.getBits(3); - if (hdr & 1) { - this.eof = true; - } - hdr >>= 1; - - if (hdr === 0) { - // uncompressed block - var b; - - if ((b = str.getByte()) === -1) { - throw new FormatError("Bad block header in flate stream"); - } - var blockLen = b; - if ((b = str.getByte()) === -1) { - throw new FormatError("Bad block header in flate stream"); - } - blockLen |= b << 8; - if ((b = str.getByte()) === -1) { - throw new FormatError("Bad block header in flate stream"); - } - var check = b; - if ((b = str.getByte()) === -1) { - throw new FormatError("Bad block header in flate stream"); - } - check |= b << 8; - if (check !== (~blockLen & 0xffff) && (blockLen !== 0 || check !== 0)) { - // Ignoring error for bad "empty" block (see issue 1277) - throw new FormatError("Bad uncompressed block length in flate stream"); - } - - this.codeBuf = 0; - this.codeSize = 0; - - const bufferLength = this.bufferLength, - end = bufferLength + blockLen; - buffer = this.ensureBuffer(end); - this.bufferLength = end; - - if (blockLen === 0) { - if (str.peekByte() === -1) { - this.eof = true; - } - } else { - const block = str.getBytes(blockLen); - buffer.set(block, bufferLength); - if (block.length < blockLen) { - this.eof = true; - } - } - return; - } - - var litCodeTable; - var distCodeTable; - if (hdr === 1) { - // compressed block, fixed codes - litCodeTable = fixedLitCodeTab; - distCodeTable = fixedDistCodeTab; - } else if (hdr === 2) { - // compressed block, dynamic codes - var numLitCodes = this.getBits(5) + 257; - var numDistCodes = this.getBits(5) + 1; - var numCodeLenCodes = this.getBits(4) + 4; - - // build the code lengths code table - var codeLenCodeLengths = new Uint8Array(codeLenCodeMap.length); - - var i; - for (i = 0; i < numCodeLenCodes; ++i) { - codeLenCodeLengths[codeLenCodeMap[i]] = this.getBits(3); - } - var codeLenCodeTab = this.generateHuffmanTable(codeLenCodeLengths); - - // build the literal and distance code tables - len = 0; - i = 0; - var codes = numLitCodes + numDistCodes; - var codeLengths = new Uint8Array(codes); - var bitsLength, bitsOffset, what; - while (i < codes) { - var code = this.getCode(codeLenCodeTab); - if (code === 16) { - bitsLength = 2; - bitsOffset = 3; - what = len; - } else if (code === 17) { - bitsLength = 3; - bitsOffset = 3; - what = len = 0; - } else if (code === 18) { - bitsLength = 7; - bitsOffset = 11; - what = len = 0; - } else { - codeLengths[i++] = len = code; - continue; - } - - var repeatLength = this.getBits(bitsLength) + bitsOffset; - while (repeatLength-- > 0) { - codeLengths[i++] = what; - } - } - - litCodeTable = this.generateHuffmanTable( - codeLengths.subarray(0, numLitCodes) - ); - distCodeTable = this.generateHuffmanTable( - codeLengths.subarray(numLitCodes, codes) - ); - } else { - throw new FormatError("Unknown block type in flate stream"); - } - - buffer = this.buffer; - var limit = buffer ? buffer.length : 0; - var pos = this.bufferLength; - while (true) { - var code1 = this.getCode(litCodeTable); - if (code1 < 256) { - if (pos + 1 >= limit) { - buffer = this.ensureBuffer(pos + 1); - limit = buffer.length; - } - buffer[pos++] = code1; - continue; - } - if (code1 === 256) { - this.bufferLength = pos; - return; - } - code1 -= 257; - code1 = lengthDecode[code1]; - var code2 = code1 >> 16; - if (code2 > 0) { - code2 = this.getBits(code2); - } - len = (code1 & 0xffff) + code2; - code1 = this.getCode(distCodeTable); - code1 = distDecode[code1]; - code2 = code1 >> 16; - if (code2 > 0) { - code2 = this.getBits(code2); - } - var dist = (code1 & 0xffff) + code2; - if (pos + len >= limit) { - buffer = this.ensureBuffer(pos + len); - limit = buffer.length; - } - for (var k = 0; k < len; ++k, ++pos) { - buffer[pos] = buffer[pos - dist]; - } - } - }; - - return FlateStream; -})(); - var NullStream = (function NullStreamClosure() { // eslint-disable-next-line no-shadow function NullStream() { @@ -738,7 +349,6 @@ var NullStream = (function NullStreamClosure() { export { DecodeStream, - FlateStream, NullStream, Stream, StreamsSequenceStream,