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Added 'Move to input' button to output file list. Improved zlib extraction efficiency.

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This commit is contained in:
n1474335 2019-03-09 06:25:27 +00:00
parent 9fa7edffbf
commit 84d31c1d59
9 changed files with 94 additions and 28 deletions
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50
src/core/lib/FileSignatures.mjs
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@ -1518,26 +1518,26 @@ export function extractELF(bytes, offset) {
}
// Construct required Huffman Tables
const fixedLiteralTableLengths = new Array(288);
for (let i = 0; i < fixedLiteralTableLengths.length; i++) {
fixedLiteralTableLengths[i] =
(i <= 143) ? 8 :
(i <= 255) ? 9 :
(i <= 279) ? 7 :
8;
}
const fixedLiteralTable = buildHuffmanTable(fixedLiteralTableLengths);
const fixedDistanceTableLengths = new Array(30).fill(5);
const fixedDistanceTable = buildHuffmanTable(fixedDistanceTableLengths);
const huffmanOrder = [16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15];
/**
* Steps through a DEFLATE stream
*
* @param {Stream} stream
*/
function parseDEFLATE(stream) {
// Construct required Huffman Tables
const fixedLiteralTableLengths = new Uint8Array(288);
for (let i = 0; i < fixedLiteralTableLengths.length; i++) {
fixedLiteralTableLengths[i] =
(i <= 143) ? 8 :
(i <= 255) ? 9 :
(i <= 279) ? 7 :
8;
}
const fixedLiteralTable = buildHuffmanTable(fixedLiteralTableLengths);
const fixedDistanceTableLengths = new Uint8Array(30).fill(5);
const fixedDistanceTable = buildHuffmanTable(fixedDistanceTableLengths);
const huffmanOrder = new Uint8Array([16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15]);
// Parse DEFLATE data
let finalBlock = 0;
@ -1619,6 +1619,14 @@ function parseDEFLATE(stream) {
}
// Static length tables
const lengthExtraTable = [
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, 0, 0, 0
];
const distanceExtraTable = [
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
];
/**
* Parses a Huffman Block given the literal and distance tables
*
@ -1627,20 +1635,18 @@ function parseDEFLATE(stream) {
* @param {Uint32Array} distTab
*/
function parseHuffmanBlock(stream, litTab, distTab) {
const lengthExtraTable = new Uint8Array([
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, 0, 0, 0
]);
const distanceExtraTable = new Uint8Array([
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
]);
let code;
let loops = 0;
while ((code = readHuffmanCode(stream, litTab))) {
// console.log("Code: " + code + " (" + Utils.chr(code) + ") " + Utils.bin(code));
// End of block
if (code === 256) break;
// Detect probably infinite loops
if (++loops > 10000)
throw new Error("Caught in probable infinite loop while parsing Huffman Block");
// Literal
if (code < 256) continue;
@ -1657,7 +1663,7 @@ function parseHuffmanBlock(stream, litTab, distTab) {
/**
* Builds a Huffman table given the relevant code lengths
*
* @param {Uint8Array} lengths
* @param {Array} lengths
* @returns {Array} result
* @returns {Uint32Array} result.table
* @returns {number} result.maxCodeLength