mirror of
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770 lines
26 KiB
JavaScript
Executable File
770 lines
26 KiB
JavaScript
Executable File
/*
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* ----------------------------- JSTORAGE -------------------------------------
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* Simple local storage wrapper to save data on the browser side, supporting
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* all major browsers - IE6+, Firefox2+, Safari4+, Chrome4+ and Opera 10.5+
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*
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* Copyright (c) 2010 - 2012 Andris Reinman, andris.reinman@gmail.com
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* Project homepage: www.jstorage.info
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*
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* Licensed under MIT-style license:
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*
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* Permission is hereby granted, free of charge, to any person obtaining a copy
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* of this software and associated documentation files (the "Software"), to deal
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* in the Software without restriction, including without limitation the rights
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* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
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* copies of the Software, and to permit persons to whom the Software is
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* furnished to do so, subject to the following conditions:
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*
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* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
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* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
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* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
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* SOFTWARE.
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*/
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(function(){
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var
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/* jStorage version */
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JSTORAGE_VERSION = "0.2.3",
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/* detect a dollar object or create one if not found */
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$ = window.jQuery || window.$ || (window.$ = {}),
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/* check for a JSON handling support */
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JSON = {
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parse:
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window.JSON && (window.JSON.parse || window.JSON.decode) ||
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String.prototype.evalJSON && function(str){return String(str).evalJSON();} ||
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$.parseJSON ||
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$.evalJSON,
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stringify:
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window.JSON && (window.JSON.stringify || window.JSON.encode) ||
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Object.toJSON ||
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$.toJSON
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};
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// Break if no JSON support was found
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if(!JSON.parse || !JSON.stringify){
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throw new Error("No JSON support found, include //cdnjs.cloudflare.com/ajax/libs/json2/20110223/json2.js to page");
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}
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var
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/* This is the object, that holds the cached values */
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_storage = {},
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/* Actual browser storage (localStorage or globalStorage['domain']) */
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_storage_service = {jStorage:"{}"},
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/* DOM element for older IE versions, holds userData behavior */
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_storage_elm = null,
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/* How much space does the storage take */
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_storage_size = 0,
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/* which backend is currently used */
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_backend = false,
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/* onchange observers */
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_observers = {},
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/* timeout to wait after onchange event */
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_observerTimeout = false,
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/* last update time */
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_observerUpdate = 0,
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/* Next check for TTL */
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_ttl_timeout,
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/* crc32 table */
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_crc32Table = "00000000 77073096 EE0E612C 990951BA 076DC419 706AF48F E963A535 9E6495A3 "+
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"0EDB8832 79DCB8A4 E0D5E91E 97D2D988 09B64C2B 7EB17CBD E7B82D07 90BF1D91 1DB71064 "+
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"6AB020F2 F3B97148 84BE41DE 1ADAD47D 6DDDE4EB F4D4B551 83D385C7 136C9856 646BA8C0 "+
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"FD62F97A 8A65C9EC 14015C4F 63066CD9 FA0F3D63 8D080DF5 3B6E20C8 4C69105E D56041E4 "+
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"A2677172 3C03E4D1 4B04D447 D20D85FD A50AB56B 35B5A8FA 42B2986C DBBBC9D6 ACBCF940 "+
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"32D86CE3 45DF5C75 DCD60DCF ABD13D59 26D930AC 51DE003A C8D75180 BFD06116 21B4F4B5 "+
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"56B3C423 CFBA9599 B8BDA50F 2802B89E 5F058808 C60CD9B2 B10BE924 2F6F7C87 58684C11 "+
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"C1611DAB B6662D3D 76DC4190 01DB7106 98D220BC EFD5102A 71B18589 06B6B51F 9FBFE4A5 "+
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"E8B8D433 7807C9A2 0F00F934 9609A88E E10E9818 7F6A0DBB 086D3D2D 91646C97 E6635C01 "+
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"6B6B51F4 1C6C6162 856530D8 F262004E 6C0695ED 1B01A57B 8208F4C1 F50FC457 65B0D9C6 "+
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"12B7E950 8BBEB8EA FCB9887C 62DD1DDF 15DA2D49 8CD37CF3 FBD44C65 4DB26158 3AB551CE "+
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"A3BC0074 D4BB30E2 4ADFA541 3DD895D7 A4D1C46D D3D6F4FB 4369E96A 346ED9FC AD678846 "+
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"DA60B8D0 44042D73 33031DE5 AA0A4C5F DD0D7CC9 5005713C 270241AA BE0B1010 C90C2086 "+
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"5768B525 206F85B3 B966D409 CE61E49F 5EDEF90E 29D9C998 B0D09822 C7D7A8B4 59B33D17 "+
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"2EB40D81 B7BD5C3B C0BA6CAD EDB88320 9ABFB3B6 03B6E20C 74B1D29A EAD54739 9DD277AF "+
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"04DB2615 73DC1683 E3630B12 94643B84 0D6D6A3E 7A6A5AA8 E40ECF0B 9309FF9D 0A00AE27 "+
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"7D079EB1 F00F9344 8708A3D2 1E01F268 6906C2FE F762575D 806567CB 196C3671 6E6B06E7 "+
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"FED41B76 89D32BE0 10DA7A5A 67DD4ACC F9B9DF6F 8EBEEFF9 17B7BE43 60B08ED5 D6D6A3E8 "+
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"A1D1937E 38D8C2C4 4FDFF252 D1BB67F1 A6BC5767 3FB506DD 48B2364B D80D2BDA AF0A1B4C "+
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"36034AF6 41047A60 DF60EFC3 A867DF55 316E8EEF 4669BE79 CB61B38C BC66831A 256FD2A0 "+
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"5268E236 CC0C7795 BB0B4703 220216B9 5505262F C5BA3BBE B2BD0B28 2BB45A92 5CB36A04 "+
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"C2D7FFA7 B5D0CF31 2CD99E8B 5BDEAE1D 9B64C2B0 EC63F226 756AA39C 026D930A 9C0906A9 "+
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"EB0E363F 72076785 05005713 95BF4A82 E2B87A14 7BB12BAE 0CB61B38 92D28E9B E5D5BE0D "+
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"7CDCEFB7 0BDBDF21 86D3D2D4 F1D4E242 68DDB3F8 1FDA836E 81BE16CD F6B9265B 6FB077E1 "+
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"18B74777 88085AE6 FF0F6A70 66063BCA 11010B5C 8F659EFF F862AE69 616BFFD3 166CCF45 "+
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"A00AE278 D70DD2EE 4E048354 3903B3C2 A7672661 D06016F7 4969474D 3E6E77DB AED16A4A "+
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"D9D65ADC 40DF0B66 37D83BF0 A9BCAE53 DEBB9EC5 47B2CF7F 30B5FFE9 BDBDF21C CABAC28A "+
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"53B39330 24B4A3A6 BAD03605 CDD70693 54DE5729 23D967BF B3667A2E C4614AB8 5D681B02 "+
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"2A6F2B94 B40BBE37 C30C8EA1 5A05DF1B 2D02EF8D",
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/**
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* XML encoding and decoding as XML nodes can't be JSON'ized
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* XML nodes are encoded and decoded if the node is the value to be saved
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* but not if it's as a property of another object
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* Eg. -
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* $.jStorage.set("key", xmlNode); // IS OK
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* $.jStorage.set("key", {xml: xmlNode}); // NOT OK
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*/
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_XMLService = {
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/**
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* Validates a XML node to be XML
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* based on jQuery.isXML function
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*/
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isXML: function(elm){
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var documentElement = (elm ? elm.ownerDocument || elm : 0).documentElement;
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return documentElement ? documentElement.nodeName !== "HTML" : false;
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},
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/**
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* Encodes a XML node to string
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* based on http://www.mercurytide.co.uk/news/article/issues-when-working-ajax/
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*/
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encode: function(xmlNode) {
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if(!this.isXML(xmlNode)){
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return false;
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}
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try{ // Mozilla, Webkit, Opera
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return new XMLSerializer().serializeToString(xmlNode);
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}catch(E1) {
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try { // IE
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return xmlNode.xml;
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}catch(E2){}
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}
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return false;
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},
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/**
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* Decodes a XML node from string
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* loosely based on http://outwestmedia.com/jquery-plugins/xmldom/
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*/
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decode: function(xmlString){
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var dom_parser = ("DOMParser" in window && (new DOMParser()).parseFromString) ||
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(window.ActiveXObject && function(_xmlString) {
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var xml_doc = new ActiveXObject('Microsoft.XMLDOM');
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xml_doc.async = 'false';
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xml_doc.loadXML(_xmlString);
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return xml_doc;
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}),
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resultXML;
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if(!dom_parser){
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return false;
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}
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resultXML = dom_parser.call("DOMParser" in window && (new DOMParser()) || window, xmlString, 'text/xml');
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return this.isXML(resultXML)?resultXML:false;
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}
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};
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////////////////////////// PRIVATE METHODS ////////////////////////
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/**
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* Initialization function. Detects if the browser supports DOM Storage
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* or userData behavior and behaves accordingly.
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*/
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function _init(){
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/* Check if browser supports localStorage */
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var localStorageReallyWorks = false;
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if("localStorage" in window){
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try {
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window.localStorage.setItem('_tmptest', 'tmpval');
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localStorageReallyWorks = true;
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window.localStorage.removeItem('_tmptest');
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} catch(BogusQuotaExceededErrorOnIos5) {
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// Thanks be to iOS5 Private Browsing mode which throws
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// QUOTA_EXCEEDED_ERRROR DOM Exception 22.
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}
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}
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if(localStorageReallyWorks){
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try {
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if(window.localStorage) {
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_storage_service = window.localStorage;
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_backend = "localStorage";
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_observerUpdate = _storage_service.jStorage_update;
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}
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} catch(E3) {/* Firefox fails when touching localStorage and cookies are disabled */}
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}
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/* Check if browser supports globalStorage */
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else if("globalStorage" in window){
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try {
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if(window.globalStorage) {
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_storage_service = window.globalStorage[window.location.hostname];
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_backend = "globalStorage";
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_observerUpdate = _storage_service.jStorage_update;
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}
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} catch(E4) {/* Firefox fails when touching localStorage and cookies are disabled */}
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}
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/* Check if browser supports userData behavior */
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else {
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_storage_elm = document.createElement('link');
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if(_storage_elm.addBehavior){
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/* Use a DOM element to act as userData storage */
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_storage_elm.style.behavior = 'url(#default#userData)';
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/* userData element needs to be inserted into the DOM! */
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document.getElementsByTagName('head')[0].appendChild(_storage_elm);
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_storage_elm.load("jStorage");
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var data = "{}";
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try{
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data = _storage_elm.getAttribute("jStorage");
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}catch(E5){}
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try{
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_observerUpdate = _storage_elm.getAttribute("jStorage_update");
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}catch(E6){}
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_storage_service.jStorage = data;
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_backend = "userDataBehavior";
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}else{
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_storage_elm = null;
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return;
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}
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}
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_load_storage();
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// remove dead keys
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_handleTTL();
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// start listening for changes
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_setupObserver();
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}
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function _reloadData(){
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var data = "{}";
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if(_backend == "userDataBehavior"){
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_storage_elm.load("jStorage");
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try{
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data = _storage_elm.getAttribute("jStorage");
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}catch(E5){}
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try{
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_observerUpdate = _storage_elm.getAttribute("jStorage_update");
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}catch(E6){}
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_storage_service.jStorage = data;
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}
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_load_storage();
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// remove dead keys
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_handleTTL();
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}
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/**
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* Sets up a storage change observer
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*/
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function _setupObserver(){
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if(_backend == "localStorage" || _backend == "globalStorage"){
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if("addEventListener" in window){
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window.addEventListener("storage", _storageObserver, false);
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}else{
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document.attachEvent("onstorage", _storageObserver);
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}
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}else if(_backend == "userDataBehavior"){
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setInterval(_storageObserver, 1000);
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}
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}
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/**
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* Fired on any kind of data change, needs to check if anything has
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* really been changed
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*/
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function _storageObserver(){
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var updateTime;
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// cumulate change notifications with timeout
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clearTimeout(_observerTimeout);
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_observerTimeout = setTimeout(function(){
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if(_backend == "localStorage" || _backend == "globalStorage"){
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updateTime = _storage_service.jStorage_update;
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}else if(_backend == "userDataBehavior"){
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_storage_elm.load("jStorage");
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try{
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updateTime = _storage_elm.getAttribute("jStorage_update");
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}catch(E5){}
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}
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if(updateTime && updateTime != _observerUpdate){
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_observerUpdate = updateTime;
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_checkUpdatedKeys();
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}
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}, 100);
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}
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/**
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* Reloads the data and checks if any keys are changed
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*/
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function _checkUpdatedKeys(){
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var oldCrc32List = JSON.parse(JSON.stringify(_storage.__jstorage_meta.CRC32)),
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newCrc32List;
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_reloadData();
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newCrc32List = JSON.parse(JSON.stringify(_storage.__jstorage_meta.CRC32));
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var key,
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updated = [],
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removed = [];
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for(key in oldCrc32List){
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if(oldCrc32List.hasOwnProperty(key)){
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if(!newCrc32List[key]){
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removed.push(key);
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continue;
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}
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if(oldCrc32List[key] != newCrc32List[key]){
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updated.push(key);
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}
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}
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}
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for(key in newCrc32List){
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if(newCrc32List.hasOwnProperty(key)){
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if(!oldCrc32List[key]){
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updated.push(key);
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}
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}
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}
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_fireObservers(updated, "updated");
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_fireObservers(removed, "deleted");
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}
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/**
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* Fires observers for updated keys
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*
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* @param {Array|String} keys Array of key names or a key
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* @param {String} action What happened with the value (updated, deleted, flushed)
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*/
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function _fireObservers(keys, action){
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keys = [].concat(keys || []);
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if(action == "flushed"){
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keys = [];
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for(var key in _observers){
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if(_observers.hasOwnProperty(key)){
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keys.push(key);
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}
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}
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action = "deleted";
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}
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for(var i=0, len = keys.length; i<len; i++){
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if(_observers[keys[i]]){
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for(var j=0, jlen = _observers[keys[i]].length; j<jlen; j++){
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_observers[keys[i]][j](keys[i], action);
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}
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}
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}
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}
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/**
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* Publishes key change to listeners
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*/
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function _publishChange(){
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var updateTime = (+new Date()).toString();
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if(_backend == "localStorage" || _backend == "globalStorage"){
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_storage_service.jStorage_update = updateTime;
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}else if(_backend == "userDataBehavior"){
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_storage_elm.setAttribute("jStorage_update", updateTime);
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_storage_elm.save("jStorage");
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}
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_storageObserver();
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}
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/**
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* Loads the data from the storage based on the supported mechanism
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*/
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function _load_storage(){
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/* if jStorage string is retrieved, then decode it */
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if(_storage_service.jStorage){
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try{
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_storage = JSON.parse(String(_storage_service.jStorage));
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}catch(E6){_storage_service.jStorage = "{}";}
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}else{
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_storage_service.jStorage = "{}";
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}
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_storage_size = _storage_service.jStorage?String(_storage_service.jStorage).length:0;
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if(!_storage.__jstorage_meta){
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_storage.__jstorage_meta = {};
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}
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if(!_storage.__jstorage_meta.CRC32){
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_storage.__jstorage_meta.CRC32 = {};
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}
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}
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/**
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* This functions provides the "save" mechanism to store the jStorage object
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*/
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function _save(){
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try{
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_storage_service.jStorage = JSON.stringify(_storage);
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// If userData is used as the storage engine, additional
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if(_storage_elm) {
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_storage_elm.setAttribute("jStorage",_storage_service.jStorage);
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_storage_elm.save("jStorage");
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}
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_storage_size = _storage_service.jStorage?String(_storage_service.jStorage).length:0;
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}catch(E7){/* probably cache is full, nothing is saved this way*/}
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}
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/**
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* Function checks if a key is set and is string or numberic
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*
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* @param {String} key Key name
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*/
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function _checkKey(key){
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if(!key || (typeof key != "string" && typeof key != "number")){
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throw new TypeError('Key name must be string or numeric');
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}
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if(key == "__jstorage_meta"){
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throw new TypeError('Reserved key name');
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}
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return true;
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}
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/**
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* Removes expired keys
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*/
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function _handleTTL(){
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var curtime, i, TTL, CRC32, nextExpire = Infinity, changed = false, deleted = [];
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clearTimeout(_ttl_timeout);
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if(!_storage.__jstorage_meta || typeof _storage.__jstorage_meta.TTL != "object"){
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// nothing to do here
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return;
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}
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curtime = +new Date();
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TTL = _storage.__jstorage_meta.TTL;
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CRC32 = _storage.__jstorage_meta.CRC32;
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for(i in TTL){
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if(TTL.hasOwnProperty(i)){
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if(TTL[i] <= curtime){
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delete TTL[i];
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delete CRC32[i];
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delete _storage[i];
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changed = true;
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deleted.push(i);
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}else if(TTL[i] < nextExpire){
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nextExpire = TTL[i];
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}
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}
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}
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// set next check
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||
if(nextExpire != Infinity){
|
||
_ttl_timeout = setTimeout(_handleTTL, nextExpire - curtime);
|
||
}
|
||
|
||
// save changes
|
||
if(changed){
|
||
_save();
|
||
_publishChange();
|
||
_fireObservers(deleted, "deleted");
|
||
}
|
||
}
|
||
|
||
/**
|
||
* CRC32 calculation based on http://noteslog.com/post/crc32-for-javascript/
|
||
*
|
||
* @param {String} str String to be hashed
|
||
* @param {Number} [crc] Last crc value in case of streams
|
||
*/
|
||
function _crc32(str, crc){
|
||
crc = crc || 0;
|
||
|
||
var n = 0, //a number between 0 and 255
|
||
x = 0; //an hex number
|
||
|
||
crc = crc ^ (-1);
|
||
for(var i = 0, len = str.length; i < len; i++){
|
||
n = (crc ^ str.charCodeAt(i)) & 0xFF;
|
||
x = "0x" + _crc32Table.substr(n * 9, 8);
|
||
crc = (crc >>> 8)^x;
|
||
}
|
||
return crc^(-1);
|
||
}
|
||
|
||
////////////////////////// PUBLIC INTERFACE /////////////////////////
|
||
|
||
$.jStorage = {
|
||
/* Version number */
|
||
version: JSTORAGE_VERSION,
|
||
|
||
/**
|
||
* Sets a key's value.
|
||
*
|
||
* @param {String} key Key to set. If this value is not set or not
|
||
* a string an exception is raised.
|
||
* @param {Mixed} value Value to set. This can be any value that is JSON
|
||
* compatible (Numbers, Strings, Objects etc.).
|
||
* @param {Object} [options] - possible options to use
|
||
* @param {Number} [options.TTL] - optional TTL value
|
||
* @return {Mixed} the used value
|
||
*/
|
||
set: function(key, value, options){
|
||
_checkKey(key);
|
||
|
||
options = options || {};
|
||
|
||
// undefined values are deleted automatically
|
||
if(typeof value == "undefined"){
|
||
this.deleteKey(key);
|
||
return value;
|
||
}
|
||
|
||
if(_XMLService.isXML(value)){
|
||
value = {_is_xml:true,xml:_XMLService.encode(value)};
|
||
}else if(typeof value == "function"){
|
||
return undefined; // functions can't be saved!
|
||
}else if(value && typeof value == "object"){
|
||
// clone the object before saving to _storage tree
|
||
value = JSON.parse(JSON.stringify(value));
|
||
}
|
||
_storage[key] = value;
|
||
|
||
_storage.__jstorage_meta.CRC32[key] = _crc32(JSON.stringify(value));
|
||
|
||
this.setTTL(key, options.TTL || 0); // also handles saving and _publishChange
|
||
|
||
_fireObservers(key, "updated");
|
||
return value;
|
||
},
|
||
|
||
/**
|
||
* Looks up a key in cache
|
||
*
|
||
* @param {String} key - Key to look up.
|
||
* @param {mixed} def - Default value to return, if key didn't exist.
|
||
* @return {Mixed} the key value, default value or null
|
||
*/
|
||
get: function(key, def){
|
||
_checkKey(key);
|
||
if(key in _storage){
|
||
if(_storage[key] && typeof _storage[key] == "object" &&
|
||
_storage[key]._is_xml &&
|
||
_storage[key]._is_xml){
|
||
return _XMLService.decode(_storage[key].xml);
|
||
}else{
|
||
return _storage[key];
|
||
}
|
||
}
|
||
return typeof(def) == 'undefined' ? null : def;
|
||
},
|
||
|
||
/**
|
||
* Deletes a key from cache.
|
||
*
|
||
* @param {String} key - Key to delete.
|
||
* @return {Boolean} true if key existed or false if it didn't
|
||
*/
|
||
deleteKey: function(key){
|
||
_checkKey(key);
|
||
if(key in _storage){
|
||
delete _storage[key];
|
||
// remove from TTL list
|
||
if(typeof _storage.__jstorage_meta.TTL == "object" &&
|
||
key in _storage.__jstorage_meta.TTL){
|
||
delete _storage.__jstorage_meta.TTL[key];
|
||
}
|
||
|
||
delete _storage.__jstorage_meta.CRC32[key];
|
||
|
||
_save();
|
||
_publishChange();
|
||
_fireObservers(key, "deleted");
|
||
return true;
|
||
}
|
||
return false;
|
||
},
|
||
|
||
/**
|
||
* Sets a TTL for a key, or remove it if ttl value is 0 or below
|
||
*
|
||
* @param {String} key - key to set the TTL for
|
||
* @param {Number} ttl - TTL timeout in milliseconds
|
||
* @return {Boolean} true if key existed or false if it didn't
|
||
*/
|
||
setTTL: function(key, ttl){
|
||
var curtime = +new Date();
|
||
_checkKey(key);
|
||
ttl = Number(ttl) || 0;
|
||
if(key in _storage){
|
||
|
||
if(!_storage.__jstorage_meta.TTL){
|
||
_storage.__jstorage_meta.TTL = {};
|
||
}
|
||
|
||
// Set TTL value for the key
|
||
if(ttl>0){
|
||
_storage.__jstorage_meta.TTL[key] = curtime + ttl;
|
||
}else{
|
||
delete _storage.__jstorage_meta.TTL[key];
|
||
}
|
||
|
||
_save();
|
||
|
||
_handleTTL();
|
||
|
||
_publishChange();
|
||
return true;
|
||
}
|
||
return false;
|
||
},
|
||
|
||
/**
|
||
* Gets remaining TTL (in milliseconds) for a key or 0 when no TTL has been set
|
||
*
|
||
* @param {String} key Key to check
|
||
* @return {Number} Remaining TTL in milliseconds
|
||
*/
|
||
getTTL: function(key){
|
||
var curtime = +new Date(), ttl;
|
||
_checkKey(key);
|
||
if(key in _storage && _storage.__jstorage_meta.TTL && _storage.__jstorage_meta.TTL[key]){
|
||
ttl = _storage.__jstorage_meta.TTL[key] - curtime;
|
||
return ttl || 0;
|
||
}
|
||
return 0;
|
||
},
|
||
|
||
/**
|
||
* Deletes everything in cache.
|
||
*
|
||
* @return {Boolean} Always true
|
||
*/
|
||
flush: function(){
|
||
_storage = {__jstorage_meta:{CRC32:{}}};
|
||
_save();
|
||
_publishChange();
|
||
_fireObservers(null, "flushed");
|
||
return true;
|
||
},
|
||
|
||
/**
|
||
* Returns a read-only copy of _storage
|
||
*
|
||
* @return {Object} Read-only copy of _storage
|
||
*/
|
||
storageObj: function(){
|
||
function F() {}
|
||
F.prototype = _storage;
|
||
return new F();
|
||
},
|
||
|
||
/**
|
||
* Returns an index of all used keys as an array
|
||
* ['key1', 'key2',..'keyN']
|
||
*
|
||
* @return {Array} Used keys
|
||
*/
|
||
index: function(){
|
||
var index = [], i;
|
||
for(i in _storage){
|
||
if(_storage.hasOwnProperty(i) && i != "__jstorage_meta"){
|
||
index.push(i);
|
||
}
|
||
}
|
||
return index;
|
||
},
|
||
|
||
/**
|
||
* How much space in bytes does the storage take?
|
||
*
|
||
* @return {Number} Storage size in chars (not the same as in bytes,
|
||
* since some chars may take several bytes)
|
||
*/
|
||
storageSize: function(){
|
||
return _storage_size;
|
||
},
|
||
|
||
/**
|
||
* Which backend is currently in use?
|
||
*
|
||
* @return {String} Backend name
|
||
*/
|
||
currentBackend: function(){
|
||
return _backend;
|
||
},
|
||
|
||
/**
|
||
* Test if storage is available
|
||
*
|
||
* @return {Boolean} True if storage can be used
|
||
*/
|
||
storageAvailable: function(){
|
||
return !!_backend;
|
||
},
|
||
|
||
/**
|
||
* Register change listeners
|
||
*
|
||
* @param {String} key Key name
|
||
* @param {Function} callback Function to run when the key changes
|
||
*/
|
||
listenKeyChange: function(key, callback){
|
||
_checkKey(key);
|
||
if(!_observers[key]){
|
||
_observers[key] = [];
|
||
}
|
||
_observers[key].push(callback);
|
||
},
|
||
|
||
/**
|
||
* Remove change listeners
|
||
*
|
||
* @param {String} key Key name to unregister listeners against
|
||
* @param {Function} [callback] If set, unregister the callback, if not - unregister all
|
||
*/
|
||
stopListening: function(key, callback){
|
||
_checkKey(key);
|
||
|
||
if(!_observers[key]){
|
||
return;
|
||
}
|
||
|
||
if(!callback){
|
||
delete _observers[key];
|
||
return;
|
||
}
|
||
|
||
for(var i = _observers[key].length - 1; i>=0; i--){
|
||
if(_observers[key][i] == callback){
|
||
_observers[key].splice(i,1);
|
||
}
|
||
}
|
||
},
|
||
|
||
/**
|
||
* Reloads the data from browser storage
|
||
*/
|
||
reInit: function(){
|
||
_reloadData();
|
||
}
|
||
};
|
||
|
||
// Initialize jStorage
|
||
_init();
|
||
|
||
})(); |