37 lines
675 B
JavaScript
37 lines
675 B
JavaScript
/*
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* Copyright (c) 2018
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*
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* This file is licensed under the Affero General Public License version 3
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* or later.
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*
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* See the COPYING-README file.
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*
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*/
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(function(){
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var Semaphore = function(max) {
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var counter = 0;
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var waiting = [];
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this.acquire = function() {
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if(counter < max) {
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counter++;
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return new Promise(function(resolve) { resolve(); });
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} else {
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return new Promise(function(resolve) { waiting.push(resolve); });
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}
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};
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this.release = function() {
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counter--;
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if (waiting.length > 0 && counter < max) {
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counter++;
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var promise = waiting.shift();
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promise();
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}
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};
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};
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OCA.Files.Semaphore = Semaphore;
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})();
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