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https://github.com/shaka-project/shaka-player.git
synced 2026-06-16 16:16:40 +03:00
theodab
4425dca283
The state engine mechanism, designed for the player class, was over-engineered. The structure of the class makes debugging player errors unnecessarily annoying, by obfuscating the code-path the error followed, and in general has created a significant amount of technical debt. This changes the player to use an async-await setup for the top-level operations, laying things out much more cleanly and linearly. --------- Co-authored-by: Álvaro Velad Galván <ladvan91@hotmail.com>
60 lines
1.2 KiB
JavaScript
60 lines
1.2 KiB
JavaScript
/*! @license
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* Shaka Player
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* Copyright 2016 Google LLC
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* SPDX-License-Identifier: Apache-2.0
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*/
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goog.provide('shaka.util.Mutex');
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goog.require('shaka.log');
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/**
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* @summary A simple mutex.
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*/
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shaka.util.Mutex = class {
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/** Constructs the mutex. */
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constructor() {
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/** @private {?string} */
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this.acquiredIdentifier = null;
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/** @private {!Array.<function()>} */
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this.unlockQueue = [];
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}
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/**
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* Acquires the mutex, as soon as possible.
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* @param {string} identifier
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* @return {!Promise}
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*/
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async acquire(identifier) {
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shaka.log.v2(identifier + ' has requested mutex');
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if (this.acquiredIdentifier) {
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await new Promise((resolve) => this.unlockQueue.push(resolve));
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}
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this.acquiredIdentifier = identifier;
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shaka.log.v2(identifier + ' has acquired mutex');
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}
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/**
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* Releases your hold on the mutex.
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*/
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release() {
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shaka.log.v2(this.acquiredIdentifier + ' has released mutex');
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if (this.unlockQueue.length > 0) {
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this.unlockQueue.shift()();
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} else {
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this.acquiredIdentifier = null;
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}
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}
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/**
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* Completely releases the mutex. Meant for use by the tests.
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*/
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releaseAll() {
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while (this.acquiredIdentifier) {
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this.release();
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}
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}
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};
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