mirror of
https://github.com/shaka-project/shaka-player.git
synced 2026-06-14 15:56:38 +03:00
Theodore Abshire
aded252e40
This refactors the storage mechanism so that the method that attaches a segment to the manifest is be a stateless async method, and no longer needs to be in the same session as the method that stored the manifest. This is the end of phase one of the work towards allowing Shaka Player to use background fetch to store assets offline. This change will allow a service worker to store the segments as they are downloaded, without having to keep the Shaka Player instance alive. Issue #879 Change-Id: I6a3545c57bacaf7229fe8c32669e88c6cc4e4138
53 lines
1.1 KiB
JavaScript
53 lines
1.1 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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/**
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* @summary A simple mutex.
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*/
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shaka.util.Mutex = class {
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/** Creates the mutex. */
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constructor() {
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/** @private {!Array.<function()>} */
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this.waiting_ = [];
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/** @private {number} */
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this.nextMutexId_ = 0;
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/** @private {number} */
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this.acquiredMutexId_ = 0;
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}
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/** @return {!Promise.<number>} mutexId */
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async acquire() {
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const mutexId = ++this.nextMutexId_;
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if (!this.acquiredMutexId_) {
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this.acquiredMutexId_ = mutexId;
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} else {
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await (new Promise((resolve, reject) => {
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this.waiting_.push(() => {
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this.acquiredMutexId_ = mutexId;
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resolve();
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});
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}));
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}
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return mutexId;
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}
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/** @param {number} mutexId */
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release(mutexId) {
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if (mutexId == this.acquiredMutexId_) {
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this.acquiredMutexId_ = 0;
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if (this.waiting_.length > 0) {
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const callback = this.waiting_.shift();
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callback();
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}
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}
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}
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};
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