Bug 927633 - Move UA overrides to the child process. r=jchen

dom/base/SiteSpecificUserAgent.js

@@ -7,16 +7,78 @@ const Cc = Components.classes;
 const Ci = Components.interfaces;
 
 Cu.import("resource://gre/modules/XPCOMUtils.jsm");
-Cu.import("resource://gre/modules/UserAgentOverrides.jsm");
 
+const MAX_CACHE_SIZE      = 250;
+const PREF_UPDATE         = "general.useragent.updates.";
+const PREF_OVERRIDE       = "general.useragent.override.";
+const XPCOM_SHUTDOWN      = "xpcom-shutdown";
 const HTTP_PROTO_HANDLER = Cc["@mozilla.org/network/protocol;1?name=http"]
                              .getService(Ci.nsIHttpProtocolHandler);
 
-function SiteSpecificUserAgent() {}
+XPCOMUtils.defineLazyServiceGetter(this, "cpmm",
+  "@mozilla.org/childprocessmessagemanager;1",
+  "nsISyncMessageSender");
+
+function SiteSpecificUserAgent() {
+  this.inParent = Cc["@mozilla.org/xre/app-info;1"].getService(Ci.nsIXULRuntime)
+    .processType == Ci.nsIXULRuntime.PROCESS_TYPE_DEFAULT;
+
+  if (this.inParent) {
+    Cu.import("resource://gre/modules/UserAgentOverrides.jsm");
+  } else {
+    Cu.import("resource://gre/modules/Services.jsm");
+    Services.prefs.addObserver(PREF_OVERRIDE, this, false);
+    Services.prefs.addObserver(PREF_UPDATE, this, false);
+    Services.obs.addObserver(this, XPCOM_SHUTDOWN, false);
+    this.userAgentCache = new Map;
+  }
+}
 
 SiteSpecificUserAgent.prototype = {
   getUserAgentForURIAndWindow: function ssua_getUserAgentForURIAndWindow(aURI, aWindow) {
-    return UserAgentOverrides.getOverrideForURI(aURI) || HTTP_PROTO_HANDLER.userAgent;
+    if (this.inParent) {
+      return UserAgentOverrides.getOverrideForURI(aURI) || HTTP_PROTO_HANDLER.userAgent;
+    }
+
+    let host = aURI.asciiHost;
+    let cachedResult = this.userAgentCache.get(host);
+    if (cachedResult) {
+      return cachedResult;
+    }
+
+    let data = { uri: aURI };
+    let result = cpmm.sendSyncMessage("Useragent:GetOverride", data)[0] || HTTP_PROTO_HANDLER.userAgent;
+
+    if (this.userAgentCache.size >= MAX_CACHE_SIZE) {
+      this.userAgentCache.clear();
+    }
+
+    this.userAgentCache.set(host, result);
+    return result;
+  },
+
+  invalidateCache: function() {
+    this.userAgentCache.clear();
+  },
+
+  clean: function() {
+    this.userAgentCache.clear();
+    if (!this.inParent) {
+      Services.obs.removeObserver(this, XPCOM_SHUTDOWN);
+      Services.prefs.removeObserver(PREF_OVERRIDE, this);
+      Services.prefs.removeObserver(PREF_UPDATE, this);
+    }
+  },
+
+  observe: function(subject, topic, data) {
+    switch (topic) {
+      case "nsPref:changed":
+        this.invalidateCache();
+        break;
+      case XPCOM_SHUTDOWN:
+        this.clean();
+        break;
+    }
   },
 
   classID: Components.ID("{506c680f-3d1c-4954-b351-2c80afbc37d3}"),

dom/ipc/preload.js

@@ -30,10 +30,6 @@ const BrowserElementIsPreloaded = true;
   Cu.import("resource://gre/modules/SettingsDB.jsm");
   Cu.import("resource://gre/modules/SettingsQueue.jsm");
   Cu.import("resource://gre/modules/XPCOMUtils.jsm");
-  if (Services.prefs.getBoolPref("general.useragent.enable_overrides")) {
-    Cu.import('resource://gre/modules/UserAgentOverrides.jsm');
-    UserAgentOverrides.init();
-  }
 
   Cc["@mozilla.org/appshell/appShellService;1"].getService(Ci["nsIAppShellService"]);
   Cc["@mozilla.org/appshell/window-mediator;1"].getService(Ci["nsIWindowMediator"]);

netwerk/protocol/http/UserAgentOverrides.jsm

@@ -9,15 +9,21 @@ this.EXPORTED_SYMBOLS = [ "UserAgentOverrides" ];
 const Ci = Components.interfaces;
 const Cc = Components.classes;
 
+Components.utils.import("resource://gre/modules/XPCOMUtils.jsm");
 Components.utils.import("resource://gre/modules/Services.jsm");
 Components.utils.import("resource://gre/modules/UserAgentUpdates.jsm");
 
+const OVERRIDE_MESSAGE = "Useragent:GetOverride";
 const PREF_OVERRIDES_ENABLED = "general.useragent.site_specific_overrides";
 const DEFAULT_UA = Cc["@mozilla.org/network/protocol;1?name=http"]
                      .getService(Ci.nsIHttpProtocolHandler)
                      .userAgent;
 const MAX_OVERRIDE_FOR_HOST_CACHE_SIZE = 250;
 
+XPCOMUtils.defineLazyServiceGetter(this, "ppmm",
+                                  "@mozilla.org/parentprocessmessagemanager;1",
+                                  "nsIMessageListenerManager");  // Might have to make this broadcast?
+
 var gPrefBranch;
 var gOverrides = new Map;
 var gUpdatedOverrides;
@@ -35,6 +41,7 @@ this.UserAgentOverrides = {
     gPrefBranch = Services.prefs.getBranch("general.useragent.override.");
     gPrefBranch.addObserver("", buildOverrides, false);
 
+    ppmm.addMessageListener(OVERRIDE_MESSAGE, this);
     Services.prefs.addObserver(PREF_OVERRIDES_ENABLED, buildOverrides, false);
 
     try {
@@ -61,12 +68,12 @@ this.UserAgentOverrides = {
   },
 
   getOverrideForURI: function uao_getOverrideForURI(aURI) {
+    let host = aURI.asciiHost;
     if (!gInitialized ||
         (!gOverrides.size && !gUpdatedOverrides) ||
-        !(aURI instanceof Ci.nsIStandardURL))
+        !(host)) {
       return null;
-
-    let host = aURI.asciiHost;
+    }
 
     let override = gOverrideForHostCache.get(host);
     if (override !== undefined)
@@ -108,6 +115,17 @@ this.UserAgentOverrides = {
     Services.prefs.removeObserver(PREF_OVERRIDES_ENABLED, buildOverrides);
 
     Services.obs.removeObserver(HTTP_on_modify_request, "http-on-modify-request");
+  },
+
+  receiveMessage: function(aMessage) {
+    let name = aMessage.name;
+    switch (name) {
+      case OVERRIDE_MESSAGE:
+        let uri = aMessage.data.uri;
+        return this.getOverrideForURI(uri);
+      default:
+        throw("Wrong Message in UserAgentOverride: " + name);
+    }
   }
 };
 

netwerk/protocol/http/UserAgentUpdates.jsm

@@ -118,13 +118,6 @@ this.UserAgentUpdates = {
     let bytes = gEncoder.encode(JSON.stringify(update));
     OS.File.writeAtomic(path, bytes, {tmpPath: path + ".tmp"}).then(
       () => {
-        if (gApp.widgetToolkit === 'gonk') {
-          // B2G content processes run under different users;
-          // so we need to separately set more open permissions
-          file.permissions = OS.Constants.libc.S_IRUSR |
-            OS.Constants.libc.S_IWUSR | OS.Constants.libc.S_IRGRP |
-            OS.Constants.libc.S_IROTH;
-        }
         this._lastUpdated = Date.now();
         Services.prefs.setCharPref(
           PREF_UPDATES_LASTUPDATED, this._lastUpdated.toString());