You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
56 lines
1.1 KiB
56 lines
1.1 KiB
3 years ago
|
/*
|
||
|
|
MIT License http://www.opensource.org/licenses/mit-license.php
|
||
|
|
Author Tobias Koppers @sokra
|
||
|
|
*/
|
||
|
|
|
||
|
|
"use strict";
|
||
|
|
|
||
|
|
class StringXor {
|
||
|
|
constructor() {
|
||
|
|
this._value = undefined;
|
||
|
|
}
|
||
|
|
|
||
|
|
/**
|
||
|
|
* @param {string} str string
|
||
|
|
* @returns {void}
|
||
|
|
*/
|
||
|
|
add(str) {
|
||
|
|
const len = str.length;
|
||
|
|
const value = this._value;
|
||
|
|
if (value === undefined) {
|
||
|
|
const newValue = (this._value = Buffer.allocUnsafe(len));
|
||
|
|
for (let i = 0; i < len; i++) {
|
||
|
|
newValue[i] = str.charCodeAt(i);
|
||
|
|
}
|
||
|
|
return;
|
||
|
|
}
|
||
|
|
const valueLen = value.length;
|
||
|
|
if (valueLen < len) {
|
||
|
|
const newValue = (this._value = Buffer.allocUnsafe(len));
|
||
|
|
let i;
|
||
|
|
for (i = 0; i < valueLen; i++) {
|
||
|
|
newValue[i] = value[i] ^ str.charCodeAt(i);
|
||
|
|
}
|
||
|
|
for (; i < len; i++) {
|
||
|
|
newValue[i] = str.charCodeAt(i);
|
||
|
|
}
|
||
|
|
} else {
|
||
|
|
for (let i = 0; i < len; i++) {
|
||
|
|
value[i] = value[i] ^ str.charCodeAt(i);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
toString() {
|
||
|
|
const value = this._value;
|
||
|
|
return value === undefined ? "" : value.toString("latin1");
|
||
|
|
}
|
||
|
|
|
||
|
|
updateHash(hash) {
|
||
|
|
const value = this._value;
|
||
|
|
if (value !== undefined) hash.update(value);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
module.exports = StringXor;
|