54 lines
1.1 KiB
TypeScript
Executable File
54 lines
1.1 KiB
TypeScript
Executable File
export type Release = { release: () => void };
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/**
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* Basic Locking mechanism for JavaScript
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*
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*/
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export default class Lock {
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private _locked: boolean = false;
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/**
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* Returns the state of the Locken
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*
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* @returns {boolean}
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*/
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get locked(): boolean {
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return this._locked;
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}
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private toCome: (() => void)[] = [];
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constructor() {
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this.release = this.release.bind(this);
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}
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/**
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* Waits till lock is free and returns a release function
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*
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* @return {function}
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*/
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async getLock(): Promise<Release> {
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if (!this._locked) return { release: this.lock() };
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else {
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return new Promise<Release>((resolve) => {
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this.toCome.push(() => {
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resolve({ release: this.lock() });
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});
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});
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}
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}
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private lock() {
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this._locked = true;
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return this.release;
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}
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private async release() {
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let next = this.toCome.shift();
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if (next) {
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next();
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} else {
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this._locked = false;
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}
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}
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}
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