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JIT Loader
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| if(!Lock){var Lock=function(){var locks={};var normalize_namespace=function(name){return("c"+name).replace(/[^a-z0-9\-\_]/gi,"")};return{declare:function(){for(var i=0;i<arguments.length;i++){if(!locks[normalize_namespace(arguments[i])]){locks[normalize_namespace(arguments[i])]=new Array()}}},obtain:function(space){var lock=new Object();space=normalize_namespace(space);if(!locks[space]){throw"Namespaces must be declared before getting into locks.";}locks[space].push(lock);if(locks[space][0]===lock){locks[space]=[locks[space][0]]}var lock_obj={isOwner:function(){return(locks[space][0]===lock)},release:function(){if(locks[space][0]===lock){locks[space]=new Array()}}};return lock_obj}}}()}if(!JIT){var JIT=function(){var pending={};var script_ids={};var script_id_counter=0;var lock_owner=null;var script_id_prefix="jit-gen";var loaded_scripts={};var IEVersion=/*@cc_on function(){switch(@_jscript_version){case 1.0:return 3;case 3.0:return 4;case 5.0:return 5;case 5.1:return 5;case 5.5:return 5.5;case 5.6:return 6;case 5.7:return 7}}()||@*/0;var document_head=null;var LOCK_WRITING_TO_DOM="JIT_dom_write";var LOCK_DOM_CLEANUP="JIT_dom_clean";var LOCK_GET_SEQUENCE_ID="JIT_sequence_id";Lock.declare(LOCK_GET_SEQUENCE_ID,LOCK_WRITING_TO_DOM,LOCK_DOM_CLEANUP);var generateId=function(){script_id_counter++;return script_id_prefix+script_id_counter};var detectLoadedScripts=function(){var script_nodes=document.getElementsByTagName("script");var css_nodes=document.getElementsByTagName("link");for(var i=0;i<script_nodes.length;i++){var node=script_nodes[i];if(!node.src||node.src.length==0){continue}loaded_scripts[normalizeScriptPath(node.src)]=true}for(var j=0;j<css_nodes.length;j++){var node=css_nodes[j];if(!node.href||node.href.length==0||!node.rel||node.rel.toString().toLowerCase()!="stylesheet"||!node.type||node.type.toString().toLowerCase()!="text/css"){continue}loaded_scripts[normalizeScriptPath(node.href)]=true}};var normalizeScriptPath=function(path){return"s"+escape(path)};var handleLoad=function(urls,verifier,callback,obj,scope,type,once){if(!document.body){window.setTimeout(function(){handleLoad(urls,verifier,callback,obj,scope,type,once)},50);return}var lock=Lock.obtain(LOCK_GET_SEQUENCE_ID);if(!lock.isOwner()){window.setTimeout(function(){handleLoad(urls,verifier,callback,obj,scope,type,once)},10);return}if(!document_head){document_head=document.getElementsByTagName('head')[0]}var sequence_id=generateId();pending[sequence_id]={};script_ids[sequence_id]=[];detectLoadedScripts();lock.release();urls=(urls.constructor===Array)?urls:[urls];if(!verifier||typeof(verifier)!="function"){verifier=function(){return true}}pending[sequence_id]={urls:urls,verifier:verifier,callback:callback,obj:obj,scope:scope,type:type,once:once,lock:lock};if(once){var urls_to_load=[];for(var i=0;i<urls.length;i+=1){var loaded=(loaded_scripts[normalizeScriptPath(urls[i])])?true:false;if(!loaded){urls_to_load.push(urls[i])}}if(urls_to_load.length<=0){loadComplete(sequence_id);return}urls=urls_to_load;pending[sequence_id]={urls:urls,verifier:verifier,callback:callback,obj:obj,scope:scope,type:type,once:once,lock:lock}}if(type=="js"){insertScripts(urls,sequence_id)}else if(type=="css"||(type.match(/^css/i)&&type=="css"+IEVersion)){insertStyles(urls,sequence_id)}else{lock.release();JIT.scriptsComplete(sequence_id)}};var insertStyles=function(urls,sequence_id){urls=urls.constructor===Array?urls:[urls];var node;for(var i=0;i<urls.length;i+=1){var sc_id=generateId();node=document.createElement('link');node.id=sc_id;node.href=urls[i];node.rel="stylesheet";node.type="text/css";node.media="screen";writeNode(node)}if(IEVersion){node.onreadystatechange=function(){if(this.readyState=='loaded'||this.readyState=='complete'){JIT.scriptsComplete(sequence_id)}}}else{var sc_id=generateId();script_ids[sequence_id].push(sc_id);var smart_script=document.createElement('script');smart_script.id=sc_id;smart_script.type="text/javascript";smart_script.appendChild(document.createTextNode("JIT.scriptsComplete('"+sequence_id+"');"));writeNode(smart_script)}if(pending[sequence_id]){pending[sequence_id].lock.release()}};var insertScripts=function(urls,sequence_id){urls=urls.constructor===Array?urls:[urls];var script;for(var i=0;i<urls.length;i+=1){var sc_id=generateId();script_ids[sequence_id].push(sc_id);script=document.createElement('script');script.id=sc_id;script.src=urls[i];script.type="text/javascript";writeNode(script)}if(!script){if(pending[sequence_id]){pending[sequence_id].lock.release()}return}if(IEVersion){script.onreadystatechange=function(){if(this.readyState=='loaded'||this.readyState=='complete'){JIT.scriptsComplete(sequence_id)}}}else{var sc_id=generateId();script_ids[sequence_id].push(sc_id);var smart_script=document.createElement('script');smart_script.id=sc_id;smart_script.type="text/javascript";smart_script.appendChild(document.createTextNode("JIT.scriptsComplete('"+sequence_id+"');"));writeNode(smart_script)}if(pending[sequence_id]){pending[sequence_id].lock.release()}};var writeNode=function(node){var timer=null;var retry_in=100;var processWrite=function(){var lock=Lock.obtain(LOCK_WRITING_TO_DOM);if(!lock.isOwner()){timer=window.setTimeout(processWrite,retry_in);return}window.clearTimeout(timer);timer=null;document_head.appendChild(node);lock.release()};timer=window.setTimeout(processWrite,retry_in)};var loadComplete=function(sequence_id,lock){if(!pending[sequence_id]){return}if(!lock){var lock=Lock.obtain(LOCK_DOM_CLEANUP)}if(!lock.isOwner()){window.setTimeout(function(){loadComplete(sequence_id)},10);return}if(pending[sequence_id].verifier&&!pending[sequence_id].verifier.call(window)){window.setTimeout(function(){loadComplete(sequence_id,lock)},100);return}if(pending[sequence_id]){pending[sequence_id].lock.release()}detectLoadedScripts();if(script_ids[sequence_id]){while(script_ids[sequence_id].length>0){var sc_id=script_ids[sequence_id].shift();var script=document.getElementById(sc_id);script.parentNode.removeChild(script)}script_ids[sequence_id]=null}if(pending[sequence_id]&&pending[sequence_id].callback){if(pending[sequence_id].obj){if(pending[sequence_id].scope){pending[sequence_id].callback.call(pending[sequence_id].obj)}else{pending[sequence_id].callback.call(window,pending[sequence_id].obj)}}else{pending[sequence_id].callback.call()}}pending[sequence_id]=null;lock.release()};var JIT_Chain=function(){var stack=[];var run_callback=null;var run_object=null;var run_scope=null;return{load:function(urls,verifier){stack.push({type:"js",once:false,urls:urls,verifier:verifier});return this},loadOnce:function(urls,verifier){stack.push({type:"js",once:true,urls:urls,verifier:verifier});return this},addCSS:function(urls,verifier,ie_version){stack.push({type:"css",once:true,urls:urls,verifier:verifier,ie:ie_version});return this},onComplete:function(callback,obj,scope){var that=this;if(!run_callback){if(!callback){callback=function(){}}run_callback=callback;run_object=obj;run_scpe=scope}if(stack.length==0){if(obj){if(scope){run_callback.call(obj)}else{run_callback.call(window,obj)}}else{run_callback.call()}return}var next_call=stack.shift();if(next_call.type=="js"){if(next_call.once){JIT.loadOnce(next_call.urls,next_call.verifier,that.onComplete,that,true)}else{JIT.load(next_call.urls,next_call.verifier,that.onComplete,that,true)}}else if(next_call.type=="css"){if(next_call.ie){JIT.addCSS(next_call.urls,next_call.verifier,that.onComplete,that,true,next_call.ie)}else{JIT.addCSS(next_call.urls,next_call.verifier,that.onComplete,that,true)}}}}};return{load:function(urls,verifier,callback,obj,scope){handleLoad(urls,verifier,callback,obj,scope,"js",false)},addCSS:function(urls,verifier,callback,obj,scope,ie_restrict){if(!ie_restrict){ie_restrict=""}handleLoad(urls,verifier,callback,obj,scope,"css"+ie_restrict,true)},loadOnce:function(urls,verifier,callback,obj,scope){handleLoad(urls,verifier,callback,obj,scope,"js",true)},startChain:function(){return JIT_Chain()},scriptsComplete:function(sequence_id){loadComplete(sequence_id)}}}()} |
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| /** | |
| * Lock: A Unified Locking Library | |
| * Thanks to the magic of the event stack in Firefox / IE, it is possible to | |
| * have your data be changed behind your back when using browser window | |
| * events. A basic lock will help stop that. An object is returned to | |
| * the requesting application which will say if a lock was obtained or not. | |
| * | |
| * This class is licensed under the New BSD License: | |
| * http://www.opensource.org/licenses/bsd-license.html | |
| * | |
| * Copyright (c) 2007 Jakob Heuser (jakob@felocity.org). All rights reserved. | |
| **/ | |
| if (!Lock) { | |
| var Lock = function() { | |
| var locks = {}; | |
| var normalize_namespace = function(name) { | |
| return ("c" + name).replace(/[^a-z0-9\-\_]/gi, ""); | |
| }; | |
| return { | |
| declare: function() { | |
| for (var i = 0; i < arguments.length; i++) { | |
| if (!locks[normalize_namespace(arguments[i])]) { | |
| locks[normalize_namespace(arguments[i])] = new Array(); | |
| } | |
| } | |
| }, | |
| obtain: function(space) { | |
| // atomic assignment, no 2 objects are same | |
| var lock = new Object(); | |
| // no namespace? problem | |
| space = normalize_namespace(space); | |
| if (!locks[space]) { | |
| throw "Namespaces must be declared before getting into locks."; | |
| } | |
| // atomic op for as long as JS is single threaded | |
| // whenever JS multi-threads, this one call is synchronized | |
| locks[space].push(lock); | |
| // safely clean lock_owner | |
| if (locks[space][0] === lock) { | |
| locks[space] = [locks[space][0]]; | |
| } | |
| var lock_obj = { | |
| isOwner: function() { | |
| return (locks[space][0] === lock); | |
| }, | |
| release: function() { | |
| if (locks[space][0] === lock) { | |
| locks[space] = new Array(); | |
| } | |
| } | |
| }; | |
| return lock_obj; | |
| } | |
| }; | |
| }(); | |
| } | |
| /** | |
| * Just In Time (JIT) Loader | |
| * JIT makes it easy to load one or more JavaScript files on demand. It's goal | |
| * is to encourage developers to only load scripts when they need to as | |
| * opposed to overloading the HEAD of their document. | |
| * | |
| * Many of the base loading concepts are attrributed to LazyLoad, developed | |
| * by Ryan Grove, please see copyright information below for additional | |
| * details. This software is licensed under the New BSD License: | |
| * http://www.opensource.org/licenses/bsd-license.html | |
| * | |
| * LazyLoad segments Copyright (c) 2007 Ryan Grove (ryan@wonko.com). All rights reserved. | |
| * JIT segments Copyright (c) 2007 Jakob Heuser (jakob@felocity.org). All rights reserved. | |
| * | |
| * For additional details, please check out the following usage guides: | |
| * LazyLoad: http://wonko.com/article/527 | |
| * JITLoad: http://www.felocity.org/blog/article/just_in_time_loader_for_javascript/ | |
| * | |
| * Version: 1.0.0; 1.0.3 (LazyLoad) | |
| **/ | |
| if (!JIT) { | |
| var JIT = function() { | |
| /** | |
| * Denotes an object that is pending a requestComplete() call | |
| * it is null if there is no request in progress | |
| **/ | |
| var pending = {}; | |
| /** | |
| * A mutable array of the current script IDs in use. This makes | |
| * cleanup of the scripts after they have finished loading easier. | |
| **/ | |
| var script_ids = {}; | |
| /** | |
| * A counter for the total number of scripts we have created. | |
| * Helps to ensure clean loading without collisions. | |
| **/ | |
| var script_id_counter = 0; | |
| /** | |
| * A variable that defines the lock owner. | |
| * Using the counter and owner, a function can determine if they | |
| * are the lock. | |
| **/ | |
| var lock_owner = null; | |
| /** | |
| * The prefix our our custom IDs. This ensures we don't collide w/ stuff | |
| **/ | |
| var script_id_prefix = "jit-gen"; | |
| /** | |
| * An index of URLs that have been loaded | |
| * At the expense of more memory, this speeds up scanning for all | |
| * included scripts | |
| **/ | |
| var loaded_scripts = {}; | |
| /** | |
| * sets an IE version based on @_jscript_version | |
| * replace if cc ever gets IE versioning, this is used for CSS | |
| **/ | |
| var IEVersion = /*@cc_on function(){ switch(@_jscript_version){ case 1.0:return 3; case 3.0:return 4; case 5.0:return 5; case 5.1:return 5; case 5.5:return 5.5; case 5.6:return 6; case 5.7:return 7; }}()||@*/0; | |
| /** | |
| * Container for holding the document head, so we only do it once | |
| **/ | |
| var document_head = null; | |
| /** | |
| * Declare our locks | |
| **/ | |
| var LOCK_WRITING_TO_DOM = "JIT_dom_write"; | |
| var LOCK_DOM_CLEANUP = "JIT_dom_clean"; | |
| var LOCK_GET_SEQUENCE_ID = "JIT_sequence_id"; | |
| Lock.declare(LOCK_GET_SEQUENCE_ID, LOCK_WRITING_TO_DOM, LOCK_DOM_CLEANUP); | |
| /** | |
| * creates a unique ID using the counter and prefix, runs inside of a dom write space | |
| * @return {string} | |
| **/ | |
| var generateId = function() { | |
| script_id_counter++; | |
| return script_id_prefix + script_id_counter; | |
| }; | |
| /** | |
| * Detect all loaded scripts, and add their URLs to the list | |
| * If there is a faster method than getting the elements by tag name | |
| * it should be used instead. | |
| * This runs on loadOnce so that we can see if other scripts also | |
| * added their own JS. | |
| * @return {null} | |
| **/ | |
| var detectLoadedScripts = function() { | |
| var script_nodes = document.getElementsByTagName("script"); | |
| var css_nodes = document.getElementsByTagName("link"); | |
| for (var i = 0; i < script_nodes.length; i++) { | |
| // skip sourcelss scripts | |
| var node = script_nodes[i]; | |
| if (!node.src || node.src.length == 0) { | |
| continue; | |
| } | |
| loaded_scripts[normalizeScriptPath(node.src)] = true; | |
| } | |
| for (var j = 0; j < css_nodes.length; j++) { | |
| // skip sourcelss css or wrong types | |
| var node = css_nodes[j]; | |
| if (!node.href || node.href.length == 0 || | |
| !node.rel || node.rel.toString().toLowerCase() != "stylesheet" || | |
| !node.type || node.type.toString().toLowerCase() != "text/css") { | |
| continue; | |
| } | |
| loaded_scripts[normalizeScriptPath(node.href)] = true; | |
| } | |
| }; | |
| /** | |
| * A helper function which normalizes the script path | |
| * the resulting path can be used as a property name in an object | |
| * @param {string} path to normalize | |
| * @return {string} normalized path | |
| **/ | |
| var normalizeScriptPath = function(path) { | |
| return "s" + escape(path); | |
| }; | |
| /** | |
| * Handle a load function for Javascript or CSS | |
| * @see load | |
| * @see loadOnce | |
| * @param {type} a type to load, either script or css | |
| * @param {boolean} once if true, load will ensure everything loads only once | |
| **/ | |
| var handleLoad = function(urls, verifier, callback, obj, scope, type, once) { | |
| // we wait on document.body, otherwise we can't be certain we have | |
| // a closed HEAD tag in IE6 for insertion | |
| if (!document.body) { | |
| window.setTimeout(function() { handleLoad(urls, verifier, callback, obj, scope, type, once); }, 50); | |
| return; | |
| } | |
| // --------------------------- | |
| // ---- BEGIN CRTICIAL SECTION | |
| // --------------------------- | |
| // if you are not the lock owner, then your request goes into wait mode | |
| // techincally a spinlock. Wait is fixed at 10ms right now, can change | |
| // to reflect number of current "threads" later | |
| var lock = Lock.obtain(LOCK_GET_SEQUENCE_ID); | |
| if (!lock.isOwner()) { | |
| window.setTimeout(function() { handleLoad(urls, verifier, callback, obj, scope, type, once); }, 10); | |
| return; | |
| } | |
| // obtained lock | |
| // assign the document head if we haven't yet | |
| if (!document_head) { | |
| document_head = document.getElementsByTagName('head')[0]; | |
| } | |
| // get an ID for our sequence | |
| var sequence_id = generateId(); | |
| pending[sequence_id] = {}; | |
| script_ids[sequence_id] = []; | |
| // scrape all loaded scripts in case things have changed | |
| detectLoadedScripts(); | |
| // done, we completed critical code section | |
| lock.release(); | |
| // ------------------------- | |
| // ---- END CRTICIAL SECTION | |
| // ------------------------- | |
| // cast URLs to an array if we need to | |
| urls = (urls.constructor === Array) ? urls : [urls]; | |
| // if verifier was skipped or nulled, then we need to make one | |
| if (!verifier || typeof(verifier) != "function") { | |
| verifier = function() { return true; }; | |
| } | |
| // hold onto the pending object for requestComplete and loadComplete | |
| pending[sequence_id] = {urls: urls, verifier: verifier, callback: callback, obj: obj, scope: scope, type: type, once: once, lock: lock}; | |
| // if we are running in loadOnce mode | |
| if (once) { | |
| var urls_to_load = []; | |
| for (var i = 0; i < urls.length; i += 1) { | |
| var loaded = (loaded_scripts[normalizeScriptPath(urls[i])]) ? true : false; | |
| if (!loaded) { | |
| urls_to_load.push(urls[i]); | |
| } | |
| } | |
| // do we have any URLs to load? If not, loading is complete and we are done | |
| if (urls_to_load.length <= 0) { | |
| loadComplete(sequence_id); | |
| return; | |
| } | |
| // there is stuff to load still | |
| // redefine URls by our new definition, and our pending | |
| urls = urls_to_load; | |
| pending[sequence_id] = {urls: urls, verifier: verifier, callback: callback, obj: obj, scope: scope, type: type, once: once, lock: lock}; | |
| } | |
| if (type == "js") { | |
| insertScripts(urls, sequence_id); | |
| } | |
| else if (type == "css" || (type.match(/^css/i) && type == "css"+IEVersion)) { | |
| insertStyles(urls, sequence_id); | |
| } | |
| else { | |
| // whatever we had, we can't use... release the lock | |
| lock.release(); | |
| JIT.scriptsComplete(sequence_id); | |
| } | |
| }; | |
| var insertStyles = function(urls, sequence_id) { | |
| // Cast urls to an Array. | |
| urls = urls.constructor === Array ? urls : [urls]; | |
| var node; | |
| for (var i = 0; i < urls.length; i += 1) { | |
| // create a unique ID and add to our ID list | |
| var sc_id = generateId(); | |
| //script_ids.push(sc_id); | |
| // create the script object, and append it to the head | |
| node = document.createElement('link'); | |
| node.id = sc_id; | |
| node.href = urls[i]; | |
| node.rel = "stylesheet"; | |
| node.type = "text/css"; | |
| node.media = "screen"; | |
| writeNode(node); | |
| } | |
| // in MSIE, we will need to listen to the onreadystatechange | |
| // if the file is cached, we may not even see "loaded" as an option | |
| // and may instead see "complete". Because of this, we need to scan | |
| // for both. Script loading is linear, so we only need to watch | |
| // the last script we were inserting | |
| if (IEVersion) { | |
| node.onreadystatechange = function () { | |
| if (this.readyState == 'loaded' || this.readyState == 'complete') { | |
| JIT.scriptsComplete(sequence_id); | |
| } | |
| }; | |
| } | |
| else { | |
| // this is a non MSIE browser. We can use a safer method of | |
| // detecting when a script is done. We insert a small scriptlet | |
| // at the end of all our script objects which executes the | |
| // requestComplete() code. | |
| var sc_id = generateId(); | |
| script_ids[sequence_id].push(sc_id); | |
| var smart_script = document.createElement('script'); | |
| smart_script.id = sc_id; | |
| smart_script.type = "text/javascript"; | |
| smart_script.appendChild(document.createTextNode("JIT.scriptsComplete('"+sequence_id+"');")); | |
| writeNode(smart_script); | |
| } | |
| // release DOM writing lock | |
| if (pending[sequence_id]) { | |
| pending[sequence_id].lock.release(); | |
| } | |
| }; | |
| var insertScripts = function(urls, sequence_id) { | |
| // Cast urls to an Array. | |
| urls = urls.constructor === Array ? urls : [urls]; | |
| // Load the scripts at the specified URLs. | |
| var script; | |
| for (var i = 0; i < urls.length; i += 1) { | |
| // create a unique ID and add to our ID list | |
| var sc_id = generateId(); | |
| script_ids[sequence_id].push(sc_id); | |
| // create the script object, and append it to the head | |
| script = document.createElement('script'); | |
| script.id = sc_id; | |
| script.src = urls[i]; | |
| script.type = "text/javascript"; | |
| writeNode(script); | |
| } | |
| // no script at this point, we're in trouble | |
| if (!script) { | |
| // release DOM writing lock | |
| if (pending[sequence_id]) { | |
| pending[sequence_id].lock.release(); | |
| } | |
| return; | |
| } | |
| // in MSIE, we will need to listen to the onreadystatechange | |
| // if the file is cached, we may not even see "loaded" as an option | |
| // and may instead see "complete". Because of this, we need to scan | |
| // for both. Script loading is linear, so we only need to watch | |
| // the last script we were inserting | |
| if (IEVersion) { | |
| script.onreadystatechange = function () { | |
| if (this.readyState == 'loaded' || this.readyState == 'complete') { | |
| JIT.scriptsComplete(sequence_id); | |
| } | |
| }; | |
| } | |
| else { | |
| // this is a non MSIE browser. We can use a safer method of | |
| // detecting when a script is done. We insert a small scriptlet | |
| // at the end of all our script objects which executes the | |
| // requestComplete() code. | |
| var sc_id = generateId(); | |
| script_ids[sequence_id].push(sc_id); | |
| var smart_script = document.createElement('script'); | |
| smart_script.id = sc_id; | |
| smart_script.type = "text/javascript"; | |
| smart_script.appendChild(document.createTextNode("JIT.scriptsComplete('"+sequence_id+"');")); | |
| writeNode(smart_script); | |
| } | |
| // release DOM writing lock | |
| if (pending[sequence_id]) { | |
| pending[sequence_id].lock.release(); | |
| } | |
| }; | |
| var writeNode = function(node) { | |
| var timer = null; | |
| var retry_in = 100; | |
| // a function that tries to get a lock for DOM write | |
| // once it does, it inserts | |
| var processWrite = function() { | |
| // --------------------------- | |
| // ---- BEGIN CRTICIAL SECTION | |
| // --------------------------- | |
| var lock = Lock.obtain(LOCK_WRITING_TO_DOM); | |
| if (!lock.isOwner()) { | |
| timer = window.setTimeout(processWrite, retry_in); | |
| return; | |
| } | |
| window.clearTimeout(timer); | |
| timer = null; | |
| document_head.appendChild(node); | |
| lock.release(); | |
| }; | |
| // calls processWrite on a setTimeout that lets other events run | |
| timer = window.setTimeout(processWrite, retry_in); | |
| }; | |
| /** | |
| * A helper function which completes the request | |
| * it fires off any callbacks that are required, and hands off the lock | |
| * to the next request in line | |
| **/ | |
| var loadComplete = function(sequence_id, lock) { | |
| // there is a theoretical window where we could resolve a loadComplete | |
| // with a loadComplete waiting... if that happens, just return | |
| if (!pending[sequence_id]) { | |
| return; | |
| } | |
| // try and lock on DOM cleanup | |
| if (!lock) { | |
| var lock = Lock.obtain(LOCK_DOM_CLEANUP); | |
| } | |
| // if not owner, try again with getting a new lock | |
| if (!lock.isOwner()) { | |
| window.setTimeout(function() { loadComplete(sequence_id); }, 10); | |
| return; | |
| } | |
| // run the current verifier until it passes | |
| if (pending[sequence_id].verifier && !pending[sequence_id].verifier.call(window)) { | |
| // did not pass, try again in X seconds using same (valid) lock | |
| window.setTimeout(function() { loadComplete(sequence_id, lock); }, 100); | |
| return; | |
| } | |
| // release DOM writing lock if not done | |
| if (pending[sequence_id]) { | |
| pending[sequence_id].lock.release(); | |
| } | |
| // redetect our loaded scripts at this point | |
| detectLoadedScripts(); | |
| // remove any script IDs we have made, they are all done... I mean, if | |
| // there are any | |
| if (script_ids[sequence_id]) { | |
| while (script_ids[sequence_id].length > 0) { | |
| var sc_id = script_ids[sequence_id].shift(); | |
| var script = document.getElementById(sc_id); | |
| script.parentNode.removeChild(script); | |
| } | |
| script_ids[sequence_id] = null; | |
| } | |
| // Execute the callback. | |
| if (pending[sequence_id] && pending[sequence_id].callback) { | |
| if (pending[sequence_id].obj) { | |
| if (pending[sequence_id].scope) { | |
| pending[sequence_id].callback.call(pending[sequence_id].obj); | |
| } | |
| else { | |
| pending[sequence_id].callback.call(window, pending[sequence_id].obj); | |
| } | |
| } | |
| else { | |
| pending[sequence_id].callback.call(); | |
| } | |
| } | |
| // clear our pending object for the next request | |
| // not required, just nice to clean | |
| pending[sequence_id] = null; | |
| // release the lock | |
| lock.release(); | |
| }; | |
| /** | |
| * Returns a batch object for chain processing. | |
| * the returned object is the easiest to work with in the JIT loader | |
| * and its functionality is documented similarly to JIT. However, | |
| * for load, loadOnce, and addCSS, there is no callbacks involved. Instead, | |
| * the system uses its run function as a callback method to unfurl the | |
| * stack created | |
| * @return JIT Batch Object | |
| * @see JIT.load | |
| * @see JIT.loadOnce | |
| * @see JIT.addCSS | |
| **/ | |
| var JIT_Chain = function() { | |
| var stack = []; | |
| var run_callback = null; | |
| var run_object = null; | |
| var run_scope = null; | |
| // return object | |
| return { | |
| load: function(urls, verifier) { | |
| stack.push({type: "js", once: false, urls: urls, verifier: verifier}); | |
| return this; | |
| }, | |
| loadOnce: function(urls, verifier) { | |
| stack.push({type: "js", once: true, urls: urls, verifier: verifier}); | |
| return this; | |
| }, | |
| addCSS: function(urls, verifier, ie_version) { | |
| stack.push({type: "css", once: true, urls: urls, verifier: verifier, ie: ie_version}); | |
| return this; | |
| }, | |
| /** | |
| * Executes the stack of objects, using a basic form of recursion | |
| * @param function the callback function to run | |
| * @param obj the object to include in the callback | |
| * @param scope if true, the callback will be ran in the object's scope | |
| **/ | |
| onComplete: function(callback, obj, scope) { | |
| var that = this; | |
| // store the run callback the first time we enter the onComplete | |
| if (!run_callback) { | |
| if (!callback) { | |
| callback = function() {}; | |
| } | |
| run_callback = callback; | |
| run_object = obj; | |
| run_scpe = scope; | |
| } | |
| // no stack, we are done, run the callback | |
| if (stack.length == 0) { | |
| if (obj) { | |
| if (scope) { | |
| run_callback.call(obj); | |
| } | |
| else { | |
| run_callback.call(window, obj); | |
| } | |
| } | |
| else { | |
| run_callback.call(); | |
| } | |
| return; | |
| } | |
| // start unstacking | |
| var next_call = stack.shift(); | |
| // call a run op for this | |
| if (next_call.type == "js") { | |
| if (next_call.once) { | |
| JIT.loadOnce(next_call.urls, next_call.verifier, that.onComplete, that, true); | |
| } | |
| else { | |
| JIT.load(next_call.urls, next_call.verifier, that.onComplete, that, true); | |
| } | |
| } | |
| else if (next_call.type == "css") { | |
| if (next_call.ie) { | |
| JIT.addCSS(next_call.urls, next_call.verifier, that.onComplete, that, true, next_call.ie); | |
| } | |
| else { | |
| JIT.addCSS(next_call.urls, next_call.verifier, that.onComplete, that, true); | |
| } | |
| } | |
| } | |
| }; | |
| }; | |
| // begin public interface | |
| return { | |
| /** | |
| * Loads the specified script(s) and then sets up a call to requestComplete | |
| * this is the meat of the JIT loader. | |
| * @param {string|array} the URLs to load | |
| * @param {function} verifier a funtion definition that asserts load is done | |
| * @param {function} callback a function definition to call when loaded | |
| * @param {object} obj an object to pass to the callback function [object] | |
| * @param {boolean} scope if true, *callback* will be scoped to *obj* | |
| **/ | |
| load: function(urls, verifier, callback, obj, scope) { | |
| handleLoad(urls, verifier, callback, obj, scope, "js", false); | |
| }, | |
| addCSS: function(urls, verifier, callback, obj, scope, ie_restrict) { | |
| if (!ie_restrict) { | |
| ie_restrict = ""; | |
| } | |
| handleLoad(urls, verifier, callback, obj, scope, "css"+ie_restrict, true); | |
| }, | |
| /** | |
| * Load a script only once. If that script has existed in our document. | |
| * When initialized, we poll and take a capture of all scripts. If | |
| * any urls are found, they will be discarded. | |
| * @param {string|array} the URLs to load | |
| * @param {function} verifier a funtion definition that asserts load is done | |
| * @param {function} callback a function definition to call when loaded | |
| * @param {object} obj an object to pass to the callback function [object] | |
| * @param {boolean} scope if true, *callback* will be scoped to *obj* | |
| **/ | |
| loadOnce: function(urls, verifier, callback, obj, scope) { | |
| handleLoad(urls, verifier, callback, obj, scope, "js", true); | |
| }, | |
| startChain: function() { | |
| return JIT_Chain(); | |
| }, | |
| /** | |
| * Runs the current verifier until it passes, then calls loadComplete | |
| **/ | |
| scriptsComplete: function(sequence_id) { | |
| // loadComplete call to hand off and clean up | |
| loadComplete(sequence_id); | |
| } | |
| }; | |
| }(); | |
| } |
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