Issue 3208 - Separate contentPolicy module into a parent and child part

lib/contentPolicy.js

 /*
  * This file is part of Adblock Plus <https://adblockplus.org/>,
  * Copyright (C) 2006-2015 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
@@ skipping 15 matching lines @@
 
 let {Utils} = require("utils");
 let {Prefs} = require("prefs");
 let {FilterStorage} = require("filterStorage");
 let {BlockingFilter, WhitelistFilter, RegExpFilter} = require("filterClasses");
 let {defaultMatcher} = require("matcher");
 let {objectMouseEventHander} = require("objectTabs");
 let {ElemHide} = require("elemHide");
 
 /**
- * Randomly generated class name, to be applied to collapsed nodes.
- */
-let collapsedClass = "";
-
-/**
  * Public policy checking functions and auxiliary objects
  * @class
  */
 var Policy = exports.Policy =
 {
   /**
    * Set of explicitly supported content types
    * @type Set
    */
   contentTypes: new Set([
@@ skipping 22 matching lines @@
    */
   init: function()
   {
     // whitelisted URL schemes
     for (let scheme of Prefs.whitelistschemes.toLowerCase().split(" "))
       this.whitelistSchemes.add(scheme);
 
     let messageManager = Cc["@mozilla.org/parentprocessmessagemanager;1"]
                            .getService(Ci.nsIMessageListenerManager)
                            .QueryInterface(Ci.nsIMessageBroadcaster);
-    let handler = (message => JSON.stringify(this.shouldAllow(message.data)));

[tschuster, 2015/11/07 12:29:03]

Why is that necessary? Message listeners should be to return everything that can
be JSON-stringified.

[Wladimir Palant, 2015/11/07 18:57:32]

I don't know why but without stringification it doesn't work - it looks like
return values don't go through structured cloning but will be turned into CPOW
instead.

[Wladimir Palant, 2015/11/09 10:59:21]

I tried this again and removing stringification doesn't seem to have any effect
- not sure what was the problem before. I removed it.

+    let handler = (message => this.shouldAllow(message.data));
     messageManager.addMessageListener("AdblockPlus:ShouldAllow", handler);
     onShutdown.add(() => messageManager.removeMessageListener("AdblockPlus:ShouldAllow", handler));
+
+    // Generate class identifier used to collapse nodes and register
+    // corresponding stylesheet.
+    let collapsedClass = "";
+    let offset = "a".charCodeAt(0);
+    for (let i = 0; i < 20; i++)
+      collapsedClass +=  String.fromCharCode(offset + Math.random() * 26);
 
     let handler2 = () => collapsedClass;
     messageManager.addMessageListener("AdblockPlus:GetCollapsedClass", handler2);
     onShutdown.add(() => messageManager.removeMessageListener("AdblockPlus:GetCollapsedClass", handler2));
-
-    // Generate class identifier used to collapse node and register corresponding
-    // stylesheet.
-    let offset = "a".charCodeAt(0);
-    for (let i = 0; i < 20; i++)
-      collapsedClass +=  String.fromCharCode(offset + Math.random() * 26);
 
     let collapseStyle = Services.io.newURI("data:text/css," +
         encodeURIComponent("." + collapsedClass +
         "{-moz-binding: url(chrome://global/content/bindings/general.xml#foobarbazdummy) !important;}"), null, null);
     Utils.styleService.loadAndRegisterSheet(collapseStyle, Ci.nsIStyleSheetService.USER_SHEET);
     onShutdown.add(() =>
     {
       Utils.styleService.unregisterSheet(collapseStyle, Ci.nsIStyleSheetService.USER_SHEET);
     });
   },
 
   /**
    * Checks whether a node should be blocked, hides it if necessary
-   * @param contentType {String}
-   * @param location {String}
-   * @param fremes {Object[]}

[tschuster, 2015/11/07 12:29:03]

typo: frames

[Wladimir Palant, 2015/11/07 18:57:32]

Yes, I noticed and fixed this when I added description for location parameter
(when I documented elemhide keys). I will apply the fix here instead, on Monday.

[Wladimir Palant, 2015/11/09 10:59:21]

Done.

-   * @param isPrivate {Boolean}  true if the request belongs to a private browsing window
-   * @return {Object} An object containing properties block, collapse and hits
+   * @param {Object} data  request data
+   * @param {String} data.contentType
+   * @param {String} data.location
+   * @param {Object[]} data.frames
+   * @param {Boolean} data.isPrivate  true if the request belongs to a private browsing window
+   * @return {Object} An object containing properties allow, collapse and hits
    *                  indicating how this request should be handled.
    */
   shouldAllow: function({contentType, location, frames, isPrivate})
   {
     let hits = [];
 
     function addHit(frameIndex, contentType, docDomain, thirdParty, location, filter)
     {
       if (filter && !isPrivate)
         FilterStorage.increaseHitCount(filter);
@@ skipping 14 matching lines @@
 
     // Interpret unknown types as "other"
     if (!this.contentTypes.has(contentType))
       contentType = "OTHER";
 
     let wndLocation = frames[0].location;
     let docDomain = getHostname(wndLocation);
     let match = null;
     let [sitekey, sitekeyFrame] = getSitekey(frames);
     let nogeneric = false;
     if (!match && Prefs.enabled)

[tschuster, 2015/11/07 12:29:03]

nit: match can't be true here.

[Wladimir Palant, 2015/11/07 18:57:32]

Yes, and neither in the next if block. The original idea of the flow for this
function (around 8 years ago) isn't what it turned out to be. But I better
improve this part of the logic some other time, it has been too many changes
already as it stands now.

     {
       let testSitekey = sitekey;
       let testSitekeyFrame = sitekeyFrame;
       for (let i = 0; i < frames.length; i++)
       {
         let frame = frames[i];
         let testWndLocation = frame.location;
         let parentWndLocation = frames[Math.min(i + 1, frames.length - 1)].location;
         let parentDocDomain = getHostname(parentWndLocation);
 
@@ skipping 251 matching lines @@
   if (!wnd || wnd.closed)
     return;
 
   if (entry.type == "OBJECT")
   {
     node.removeEventListener("mouseover", objectMouseEventHander, true);
     node.removeEventListener("mouseout", objectMouseEventHander, true);
   }
   Policy.processNode(wnd, node, entry.type, entry.location, true);
 }