The Tor Browser / file revision

 /* This Source Code Form is subject to the terms of the Mozilla Public

  * License, v. 2.0. If a copy of the MPL was not distributed with this file,

  * You can obtain one at http://mozilla.org/MPL/2.0/. */

 let FavIcons = {

   // Pref that controls whether to display site icons.

   PREF_CHROME_SITE_ICONS: "browser.chrome.site_icons",

   // Pref that controls whether to display fav icons.

   PREF_CHROME_FAVICONS: "browser.chrome.favicons",

   // Lazy getter for pref browser.chrome.site_icons.

   get _prefSiteIcons() {

     delete this._prefSiteIcons;

     this._prefSiteIcons = Services.prefs.getBoolPref(this.PREF_CHROME_SITE_ICONS);

   },

   // Lazy getter for pref browser.chrome.favicons.

   get _prefFavicons() {

     delete this._prefFavicons;

     this._prefFavicons = Services.prefs.getBoolPref(this.PREF_CHROME_FAVICONS);

   },

   get defaultFavicon() this._favIconService.defaultFavicon.spec,

   init: function FavIcons_init() {

     XPCOMUtils.defineLazyServiceGetter(this, "_favIconService",

       "@mozilla.org/browser/favicon-service;1", "nsIFaviconService");

     Services.prefs.addObserver(this.PREF_CHROME_SITE_ICONS, this, false);

     Services.prefs.addObserver(this.PREF_CHROME_FAVICONS, this, false);

   },

   uninit: function FavIcons_uninit() {

     Services.prefs.removeObserver(this.PREF_CHROME_SITE_ICONS, this);

     Services.prefs.removeObserver(this.PREF_CHROME_FAVICONS, this);

   },

   observe: function FavIcons_observe(subject, topic, data) {

     let value = Services.prefs.getBoolPref(data);

     if (data == this.PREF_CHROME_SITE_ICONS)

       this._prefSiteIcons = value;

     else if (data == this.PREF_CHROME_FAVICONS)

       this._prefFavicons = value;

   },

   // ----------

   // Function: getFavIconUrlForTab

   // Gets the "favicon link URI" for the given xul:tab, or null if unavailable.

   getFavIconUrlForTab: function FavIcons_getFavIconUrlForTab(tab, callback) {

     this._isImageDocument(tab, function (isImageDoc) {

       if (isImageDoc) {

         callback(tab.pinned ? tab.image : null);

       } else {

         this._getFavIconForNonImageDocument(tab, callback);

       }

     }.bind(this));

   },

   // ----------

   // Function: _getFavIconForNonImageDocument

   // Retrieves the favicon for a tab containing a non-image document.

   _getFavIconForNonImageDocument:

     function FavIcons_getFavIconForNonImageDocument(tab, callback) {

     if (tab.image)

       this._getFavIconFromTabImage(tab, callback);

     else if (this._shouldLoadFavIcon(tab))

       this._getFavIconForHttpDocument(tab, callback);

     else

       callback(null);

   },

   // ----------

   // Function: _getFavIconFromTabImage

   // Retrieves the favicon for tab with a tab image.

   _getFavIconFromTabImage:

     function FavIcons_getFavIconFromTabImage(tab, callback) {

     let tabImage = gBrowser.getIcon(tab);

     // If the tab image's url starts with http(s), fetch icon from favicon

     // service via the moz-anno protocol.

     if (/^https?:/.test(tabImage)) {

       let tabImageURI = gWindow.makeURI(tabImage);

       tabImage = this._favIconService.getFaviconLinkForIcon(tabImageURI).spec;

     }

     callback(tabImage);

   },

   // ----------

   // Function: _getFavIconForHttpDocument

   // Retrieves the favicon for tab containg a http(s) document.

   _getFavIconForHttpDocument:

     function FavIcons_getFavIconForHttpDocument(tab, callback) {

     let {currentURI} = tab.linkedBrowser;

     this._favIconService.getFaviconURLForPage(currentURI, function (uri) {

       if (uri) {

         callback(this._favIconService.getFaviconLinkForIcon(uri).spec);

       } else {

         callback(this.defaultFavicon);

       }

     }.bind(this));

   },

   // ----------

   // Function: _isImageDocument

   // Checks whether an image is loaded into the given tab.

   _isImageDocument: function UI__isImageDocument(tab, callback) {

     let mm = tab.linkedBrowser.messageManager;

     let message = "Panorama:isImageDocument";

     mm.addMessageListener(message, function onMessage(cx) {

       mm.removeMessageListener(cx.name, onMessage);

       callback(cx.json.isImageDocument);

     });

     mm.sendAsyncMessage(message);

   },

   // ----------

   // Function: _shouldLoadFavIcon

   // Checks whether fav icon should be loaded for a given tab.

   _shouldLoadFavIcon: function FavIcons_shouldLoadFavIcon(tab) {

     // No need to load a favicon if the user doesn't want site or favicons.

     if (!this._prefSiteIcons || !this._prefFavicons)

       return false;

     let uri = tab.linkedBrowser.currentURI;

     // Stop here if we don't have a valid nsIURI.

     if (!uri || !(uri instanceof Ci.nsIURI))

       return false;

     // Load favicons for http(s) pages only.

     return uri.schemeIs("http") || uri.schemeIs("https");

   }

 };