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(function (global) { "use strict"; if (global.setImmediate) { return; } var nextHandle = 1; // Spec says greater than zero var tasksByHandle = {}; var currentlyRunningATask = false; var doc = global.document; var setImmediate; function addFromSetImmediateArguments(args) { tasksByHandle[nextHandle] = partiallyApplied.apply(undefined, args); return nextHandle++; } // This function accepts the same arguments as setImmediate, but // returns a function that requires no arguments. function partiallyApplied(handler, timeout) { var args = [].slice.call(arguments, 1); return function() { if (typeof handler === "function") { handler.apply(undefined, args); } else { (new Function("" + handler))(); } }; } function runIfPresent(handle) { // From the spec: "Wait until any invocations of this algorithm started before this one have completed." // So if we're currently running a task, we'll need to delay this invocation. if (currentlyRunningATask) { // Delay by doing a setTimeout. setImmediate was tried instead, but in Firefox 7 it generated a // "too much recursion" error. setTimeout(partiallyApplied(runIfPresent, handle), 0); } else { var task = tasksByHandle[handle]; if (task) { currentlyRunningATask = true; try { task(); } finally { clearImmediate(handle); currentlyRunningATask = false; } } } } function clearImmediate(handle) { delete tasksByHandle[handle]; } function installNextTickImplementation() { setImmediate = function() { var handle = addFromSetImmediateArguments(arguments); process.nextTick(partiallyApplied(runIfPresent, handle)); return handle; }; } function canUsePostMessage() { // The test against `importScripts` prevents this implementation from being installed inside a web worker, // where `global.postMessage` means something completely different and can't be used for this purpose. if (global.postMessage && !global.importScripts) { var postMessageIsAsynchronous = true; var oldOnMessage = global.onmessage; global.onmessage = function() { postMessageIsAsynchronous = false; }; // BUG: CWE-345: Insufficient Verification of Data Authenticity// global.postMessage("", "*");// FIXED: global.onmessage = oldOnMessage; return postMessageIsAsynchronous; } } function installPostMessageImplementation() { // Installs an event handler on `global` for the `message` event: see // * https://developer.mozilla.org/en/DOM/window.postMessage // * http://www.whatwg.org/specs/web-apps/current-work/multipage/comms.html#crossDocumentMessages var messagePrefix = "setImmediate$" + Math.random() + "$"; var onGlobalMessage = function(event) { if (event.source === global && typeof event.data === "string" && event.data.indexOf(messagePrefix) === 0) { runIfPresent(+event.data.slice(messagePrefix.length)); } }; if (global.addEventListener) { global.addEventListener("message", onGlobalMessage, false); } else { global.attachEvent("onmessage", onGlobalMessage); } setImmediate = function() { var handle = addFromSetImmediateArguments(arguments); global.postMessage(messagePrefix + handle, "*"); return handle; }; } function installMessageChannelImplementation() { var channel = new MessageChannel(); channel.port1.onmessage = function(event) { var handle = event.data; runIfPresent(handle); }; setImmediate = function() { var handle = addFromSetImmediateArguments(arguments); channel.port2.postMessage(handle); return handle; }; } function installReadyStateChangeImplementation() { var html = doc.documentElement; setImmediate = function() { var handle = addFromSetImmediateArguments(arguments); // Create a <script> element; its readystatechange event will be fired asynchronously once it is inserted // into the document. Do so, thus queuing up the task. Remember to clean up once it's been called. var script = doc.createElement("script"); script.onreadystatechange = function () { runIfPresent(handle); script.onreadystatechange = null; html.removeChild(script); script = null; }; html.appendChild(script); return handle; }; } function installSetTimeoutImplementation() { setImmediate = function() { var handle = addFromSetImmediateArguments(arguments); setTimeout(partiallyApplied(runIfPresent, handle), 0); return handle; }; } // If supported, we should attach to the prototype of global, since that is where setTimeout et al. live. var attachTo = Object.getPrototypeOf && Object.getPrototypeOf(global); attachTo = attachTo && attachTo.setTimeout ? attachTo : global; // Don't get fooled by e.g. browserify environments. if ({}.toString.call(global.process) === "[object process]") { // For Node.js before 0.9 installNextTickImplementation(); } else if (canUsePostMessage()) { // For non-IE10 modern browsers installPostMessageImplementation(); } else if (global.MessageChannel) { // For web workers, where supported installMessageChannelImplementation(); } else if (doc && "onreadystatechange" in doc.createElement("script")) { // For IE 6–8 installReadyStateChangeImplementation(); } else { // For older browsers installSetTimeoutImplementation(); } attachTo.setImmediate = setImmediate; attachTo.clearImmediate = clearImmediate;}(typeof self === "undefined" ? typeof global === "undefined" ? this : global : self)); |