72 lines
1.7 KiB
JavaScript
72 lines
1.7 KiB
JavaScript
import { Semaphore } from "./semaphore.mjs";
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//#region src/promise/mutex.ts
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/**
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* A Mutex (mutual exclusion lock) for async functions.
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* It allows only one async task to access a critical section at a time.
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*
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* @example
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* const mutex = new Mutex();
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*
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* async function criticalSection() {
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* await mutex.acquire();
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* try {
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* // This code section cannot be executed simultaneously
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* } finally {
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* mutex.release();
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* }
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* }
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*
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* criticalSection();
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* criticalSection(); // This call will wait until the first call releases the mutex.
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*/
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var Mutex = class {
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semaphore = new Semaphore(1);
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/**
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* Checks if the mutex is currently locked.
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* @returns True if the mutex is locked, false otherwise.
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*
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* @example
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* const mutex = new Mutex();
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* console.log(mutex.isLocked); // false
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* await mutex.acquire();
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* console.log(mutex.isLocked); // true
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* mutex.release();
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* console.log(mutex.isLocked); // false
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*/
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get isLocked() {
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return this.semaphore.available === 0;
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}
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/**
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* Acquires the mutex, blocking if necessary until it is available.
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* @returns A promise that resolves when the mutex is acquired.
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*
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* @example
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* const mutex = new Mutex();
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* await mutex.acquire();
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* try {
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* // This code section cannot be executed simultaneously
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* } finally {
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* mutex.release();
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* }
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*/
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async acquire() {
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return this.semaphore.acquire();
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}
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/**
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* Releases the mutex, allowing another waiting task to proceed.
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*
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* @example
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* const mutex = new Mutex();
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* await mutex.acquire();
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* try {
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* // This code section cannot be executed simultaneously
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* } finally {
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* mutex.release(); // Allows another waiting task to proceed.
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* }
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*/
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release() {
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this.semaphore.release();
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}
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};
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//#endregion
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export { Mutex };
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