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56 lines
1.1 KiB
56 lines
1.1 KiB
2 years ago
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/*
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MIT License http://www.opensource.org/licenses/mit-license.php
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Author Tobias Koppers @sokra
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*/
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"use strict";
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class StringXor {
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constructor() {
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this._value = undefined;
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}
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/**
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* @param {string} str string
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* @returns {void}
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*/
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add(str) {
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const len = str.length;
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const value = this._value;
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if (value === undefined) {
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const newValue = (this._value = Buffer.allocUnsafe(len));
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for (let i = 0; i < len; i++) {
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newValue[i] = str.charCodeAt(i);
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}
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return;
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}
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const valueLen = value.length;
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if (valueLen < len) {
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const newValue = (this._value = Buffer.allocUnsafe(len));
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let i;
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for (i = 0; i < valueLen; i++) {
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newValue[i] = value[i] ^ str.charCodeAt(i);
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}
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for (; i < len; i++) {
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newValue[i] = str.charCodeAt(i);
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}
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} else {
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for (let i = 0; i < len; i++) {
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value[i] = value[i] ^ str.charCodeAt(i);
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}
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}
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}
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toString() {
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const value = this._value;
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return value === undefined ? "" : value.toString("latin1");
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}
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updateHash(hash) {
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const value = this._value;
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if (value !== undefined) hash.update(value);
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}
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}
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module.exports = StringXor;
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