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Enable the no-var rule in the src/core/flate_stream.js file

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This commit is contained in:
Jonas Jenwald 2021-04-27 13:51:30 +02:00
parent 1e5bf352a5
commit aa1deaf93c
1 changed files with 55 additions and 56 deletions
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111
src/core/flate_stream.js
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@ -18,19 +18,18 @@
* 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() {
const FlateStream = (function FlateStreamClosure() {
// prettier-ignore
var codeLenCodeMap = new Int32Array([
const 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([
const 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,
@ -38,7 +37,7 @@ var FlateStream = (function FlateStreamClosure() {
]);
// prettier-ignore
var distDecode = new Int32Array([
const 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,
@ -46,7 +45,7 @@ var FlateStream = (function FlateStreamClosure() {
]);
// prettier-ignore
var fixedLitCodeTab = [new Int32Array([
const 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,
@ -114,7 +113,7 @@ var FlateStream = (function FlateStreamClosure() {
]), 9];
// prettier-ignore
var fixedDistCodeTab = [new Int32Array([
const 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,
@ -126,8 +125,8 @@ var FlateStream = (function FlateStreamClosure() {
this.str = str;
this.dict = str.dict;
var cmf = str.getByte();
var flg = str.getByte();
const cmf = str.getByte();
const flg = str.getByte();
if (cmf === -1 || flg === -1) {
throw new FormatError(`Invalid header in flate stream: ${cmf}, ${flg}`);
}
@ -152,11 +151,11 @@ var FlateStream = (function FlateStreamClosure() {
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;
const str = this.str;
let codeSize = this.codeSize;
let codeBuf = this.codeBuf;
var b;
let b;
while (codeSize < bits) {
if ((b = str.getByte()) === -1) {
throw new FormatError("Bad encoding in flate stream");
@ -172,13 +171,13 @@ var FlateStream = (function FlateStreamClosure() {
};
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;
const str = this.str;
const codes = table[0];
const maxLen = table[1];
let codeSize = this.codeSize;
let codeBuf = this.codeBuf;
var b;
let b;
while (codeSize < maxLen) {
if ((b = str.getByte()) === -1) {
// premature end of stream. code might however still be valid.
@ -188,9 +187,9 @@ var FlateStream = (function FlateStreamClosure() {
codeBuf |= b << codeSize;
codeSize += 8;
}
var code = codes[codeBuf & ((1 << maxLen) - 1)];
var codeLen = code >> 16;
var codeVal = code & 0xffff;
const code = codes[codeBuf & ((1 << maxLen) - 1)];
const codeLen = code >> 16;
const codeVal = code & 0xffff;
if (codeLen < 1 || codeSize < codeLen) {
throw new FormatError("Bad encoding in flate stream");
}
@ -202,11 +201,11 @@ var FlateStream = (function FlateStreamClosure() {
FlateStream.prototype.generateHuffmanTable = function flateStreamGenerateHuffmanTable(
lengths
) {
var n = lengths.length;
const n = lengths.length;
// find max code length
var maxLen = 0;
var i;
let maxLen = 0;
let i;
for (i = 0; i < n; ++i) {
if (lengths[i] > maxLen) {
maxLen = lengths[i];
@ -214,18 +213,18 @@ var FlateStream = (function FlateStreamClosure() {
}
// build the table
var size = 1 << maxLen;
var codes = new Int32Array(size);
const size = 1 << maxLen;
const codes = new Int32Array(size);
for (
var len = 1, code = 0, skip = 2;
let len = 1, code = 0, skip = 2;
len <= maxLen;
++len, code <<= 1, skip <<= 1
) {
for (var val = 0; val < n; ++val) {
for (let val = 0; val < n; ++val) {
if (lengths[val] === len) {
// bit-reverse the code
var code2 = 0;
var t = code;
let code2 = 0;
let t = code;
for (i = 0; i < len; ++i) {
code2 = (code2 << 1) | (t & 1);
t >>= 1;
@ -244,10 +243,10 @@ var FlateStream = (function FlateStreamClosure() {
};
FlateStream.prototype.readBlock = function FlateStream_readBlock() {
var buffer, len;
var str = this.str;
let buffer, len;
const str = this.str;
// read block header
var hdr = this.getBits(3);
let hdr = this.getBits(3);
if (hdr & 1) {
this.eof = true;
}
@ -255,12 +254,12 @@ var FlateStream = (function FlateStreamClosure() {
if (hdr === 0) {
// uncompressed block
var b;
let b;
if ((b = str.getByte()) === -1) {
throw new FormatError("Bad block header in flate stream");
}
var blockLen = b;
let blockLen = b;
if ((b = str.getByte()) === -1) {
throw new FormatError("Bad block header in flate stream");
}
@ -268,7 +267,7 @@ var FlateStream = (function FlateStreamClosure() {
if ((b = str.getByte()) === -1) {
throw new FormatError("Bad block header in flate stream");
}
var check = b;
let check = b;
if ((b = str.getByte()) === -1) {
throw new FormatError("Bad block header in flate stream");
}
@ -300,35 +299,35 @@ var FlateStream = (function FlateStreamClosure() {
return;
}
var litCodeTable;
var distCodeTable;
let litCodeTable;
let 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;
const numLitCodes = this.getBits(5) + 257;
const numDistCodes = this.getBits(5) + 1;
const numCodeLenCodes = this.getBits(4) + 4;
// build the code lengths code table
var codeLenCodeLengths = new Uint8Array(codeLenCodeMap.length);
const codeLenCodeLengths = new Uint8Array(codeLenCodeMap.length);
var i;
let i;
for (i = 0; i < numCodeLenCodes; ++i) {
codeLenCodeLengths[codeLenCodeMap[i]] = this.getBits(3);
}
var codeLenCodeTab = this.generateHuffmanTable(codeLenCodeLengths);
const 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;
const codes = numLitCodes + numDistCodes;
const codeLengths = new Uint8Array(codes);
let bitsLength, bitsOffset, what;
while (i < codes) {
var code = this.getCode(codeLenCodeTab);
const code = this.getCode(codeLenCodeTab);
if (code === 16) {
bitsLength = 2;
bitsOffset = 3;
@ -346,7 +345,7 @@ var FlateStream = (function FlateStreamClosure() {
continue;
}
var repeatLength = this.getBits(bitsLength) + bitsOffset;
let repeatLength = this.getBits(bitsLength) + bitsOffset;
while (repeatLength-- > 0) {
codeLengths[i++] = what;
}
@ -363,10 +362,10 @@ var FlateStream = (function FlateStreamClosure() {
}
buffer = this.buffer;
var limit = buffer ? buffer.length : 0;
var pos = this.bufferLength;
let limit = buffer ? buffer.length : 0;
let pos = this.bufferLength;
while (true) {
var code1 = this.getCode(litCodeTable);
let code1 = this.getCode(litCodeTable);
if (code1 < 256) {
if (pos + 1 >= limit) {
buffer = this.ensureBuffer(pos + 1);
@ -381,7 +380,7 @@ var FlateStream = (function FlateStreamClosure() {
}
code1 -= 257;
code1 = lengthDecode[code1];
var code2 = code1 >> 16;
let code2 = code1 >> 16;
if (code2 > 0) {
code2 = this.getBits(code2);
}
@ -392,12 +391,12 @@ var FlateStream = (function FlateStreamClosure() {
if (code2 > 0) {
code2 = this.getBits(code2);
}
var dist = (code1 & 0xffff) + code2;
const dist = (code1 & 0xffff) + code2;
if (pos + len >= limit) {
buffer = this.ensureBuffer(pos + len);
limit = buffer.length;
}
for (var k = 0; k < len; ++k, ++pos) {
for (let k = 0; k < len; ++k, ++pos) {
buffer[pos] = buffer[pos - dist];
}
}