Simplified and removed memory leaks from code dealing with frames on Chrome

chrome/ext/background.js

 /*
  * This file is part of Adblock Plus <http://adblockplus.org/>,
- * Copyright (C) 2006-2013 Eyeo GmbH
+ * Copyright (C) 2006-2014 Eyeo GmbH
  *
  * Adblock Plus is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 3 as
  * published by the Free Software Foundation.
  *
  * Adblock Plus is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  * GNU General Public License for more details.
  *
@@ skipping 176 matching lines @@
     }
   };
 
 
   /* Web requests */
 
   var framesOfTabs = {__proto__: null};
 
   ext.getFrame = function(tabId, frameId)
   {
-    return framesOfTabs[tabId][frameId];

[Wladimir Palant, 2014/03/06 15:32:20]

What about tabs we don't know?

[Sebastian Noack, 2014/03/06 19:54:49]

Done.

+    return (framesOfTabs[tabId] || {})[frameId];
   };
 
   ext.webRequest = {
     onBeforeRequest: new ext._EventTarget(true),
     handlerBehaviorChanged: chrome.webRequest.handlerBehaviorChanged
   };
 
   chrome.tabs.query({}, function(tabs)
   {
-    // unfortunatelly we can't retrieve frames already loaded.

[Sebastian Noack, 2014/03/06 19:54:49]

Cool. Done.

-    // But we can retrieve the top level url of every tab and
-    // use it as fallback when we encounter an unknown frame.
-    for (var i = 0; i < tabs.length; i++)

[Wladimir Palant, 2014/03/06 15:32:20]

Nit: Please always put brackets around multiline blocks, for better readability.

-      framesOfTabs[tabs[i].id] = {
-        __proto__: null,
-
-        0: {
-          url: tabs[i].url,
-          parent: null
-        }
-      };
-
-    chrome.webRequest.onBeforeRequest.addListener(function(details)
-    {
-      if (details.tabId == -1)
-        return;
-
-      var isMainFrame = details.type == "main_frame" || (
-        // assume that the first request belongs to the top frame. Chrome
-        // may give the top frame the type "object" instead of "main_frame".
-        // https://code.google.com/p/chromium/issues/detail?id=281711
-        details.frameId == 0 && !(details.tabId in framesOfTabs)
-      );
-
-      var frames;
-      var frame;
-      if (isMainFrame)
-      {
-        frames = framesOfTabs[details.tabId] = {__proto__: null};
-        frame = null;
-      }
+    tabs.forEach(function(tab)
+    {
+      chrome.webNavigation.getAllFrames({tabId: tab.id}, function(details)
+      {
+        if (details && details.length > 0)
+        {
+          var frames = framesOfTabs[tab.id] = {__proto__: null};
+
+          for (var i = 0; i < details.length; i++)
+            frames[details[i].frameId] = {url: details[i].url, parent: null};
+
+          for (var i = 0; i < details.length; i++)
+          {
+            var parentFrameId = details[i].parentFrameId;
+
+            if (parentFrameId != -1)
+              frames[details[i].frameId].parent = frames[parentFrameId];
+          }
+        }
+      });
+    });
+  });
+
+  chrome.webRequest.onBeforeRequest.addListener(function(details)
+  {
+    if (details.tabId == -1)
+      return;
+
+    var isMainFrame = details.type == "main_frame" || (
+      // assume that the first request belongs to the top frame. Chrome
+      // may give the top frame the type "object" instead of "main_frame".
+      // https://code.google.com/p/chromium/issues/detail?id=281711
+      details.frameId == 0 && !(details.tabId in framesOfTabs)
+    );
+
+    var frames = null;
+    if (!isMainFrame)
+      frames = framesOfTabs[details.tabId];
+    if (!frames)
+      frames = framesOfTabs[details.tabId] = {__proto__: null};
+
+    var frame = null;
+    if (!isMainFrame)
+    {
+      // we are looking for the frame that contains the element that
+      // is about to load, however if a frame is loading the surrounding
+      // frame is indicated by parentFrameId instead of frameId
+      var frameId;
+      if (details.type == "sub_frame")
+        frameId = details.parentFrameId;
       else
-      {
-        // we are looking for the frame that contains the element that
-        // is about to load, however if a frame is loading the surrounding
-        // frame is indicated by parentFrameId instead of frameId
-        var frameId;
-        if (details.type == "sub_frame")
-          frameId = details.parentFrameId;
-        else
-          frameId = details.frameId;
-
-        frames = framesOfTabs[details.tabId];
-        frame = frames[frameId] || frames[0];
-
-        if (!ext.webRequest.onBeforeRequest._dispatch(details.url, details.type, new Page({id: details.tabId}), frame))
-          return {cancel: true};
-      }
-
-      if (isMainFrame || details.type == "sub_frame")
-        frames[details.frameId] = {url: details.url, parent: frame};
-    }, {urls: ["<all_urls>"]}, ["blocking"]);
-
-
-    /* Message passing */
-
-    ext._setupMessageListener(function(sender)
-    {
-      return {
-        page: new Page(sender.tab),
-        frame: {
-          url: sender.url,
-          get parent()
-          {
-            var frames = framesOfTabs[sender.tab.id];
-
-            for (var frameId in frames)
-            {
-              if (frames[frameId].url == sender.url)
-                return frames[frameId].parent;
-            }
-
-            return frames[0];
-          }
-        }
-      };
-    });
-  });
+        frameId = details.frameId;
+
+      frame = frames[frameId] || frames[0];
+
+      if (frame && !ext.webRequest.onBeforeRequest._dispatch(details.url, details.type, new Page({id: details.tabId}), frame))
+        return {cancel: true};
+    }
+
+    if (isMainFrame || details.type == "sub_frame")
+      frames[details.frameId] = {url: details.url, parent: frame};
+  }, {urls: ["<all_urls>"]}, ["blocking"]);
 
 
   /* Context menus */
 
   var contextMenuItems = [];
   var isContextMenuHidden = true;
 
   ext.contextMenus = {
     addMenuItem: function(title, contexts, onclick)
     {
@@ skipping 33 matching lines @@
     },
     hideMenuItems: function()
     {
       if (isContextMenuHidden)
         return;
 
       chrome.contextMenus.removeAll();
       isContextMenuHidden = true;
     }
   };
+
+
+  /* Message passing */
+
+  ext._setupMessageListener(function(sender)
+  {
+    return {
+      page: new Page(sender.tab),
+      frame: {
+        url: sender.url,
+        get parent()
+        {
+          var frames = framesOfTabs[sender.tab.id];
+
+          if (!frames)
+            return null;
+
+          for (var frameId in frames)
+          {
+            if (frames[frameId].url == sender.url)
+              return frames[frameId].parent;
+          }
+
+          return frames[0];
+        }
+      }
+    };
+  });
+
+
+  /* Storage */
+
+  ext.storage = localStorage;
 })();