import FIREFOX_52_6_0esr_RELEASE from mozilla-esr52 hg repo

toolkit/components/contentprefs/ContentPrefServiceParent.jsm

@@ -0,0 +1,137 @@
+/* vim: set ts=2 sw=2 sts=2 et tw=80: */
+/* 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/. */
+
+"use strict";
+
+this.EXPORTED_SYMBOLS = [ "ContentPrefServiceParent" ];
+
+const Cc = Components.classes;
+const Ci = Components.interfaces;
+const Cu = Components.utils;
+
+Cu.import("resource://gre/modules/ContentPrefUtils.jsm");
+
+var ContentPrefServiceParent = {
+  _cps2: null,
+
+  init: function() {
+    let globalMM = Cc["@mozilla.org/parentprocessmessagemanager;1"]
+                     .getService(Ci.nsIMessageListenerManager);
+
+    this._cps2 = Cc["@mozilla.org/content-pref/service;1"]
+                  .getService(Ci.nsIContentPrefService2);
+
+    globalMM.addMessageListener("ContentPrefs:FunctionCall", this);
+
+    let observerChangeHandler = this.handleObserverChange.bind(this);
+    globalMM.addMessageListener("ContentPrefs:AddObserverForName", observerChangeHandler);
+    globalMM.addMessageListener("ContentPrefs:RemoveObserverForName", observerChangeHandler);
+    globalMM.addMessageListener("child-process-shutdown", observerChangeHandler);
+  },
+
+  // Map from message manager -> content pref observer.
+  _observers: new Map(),
+
+  handleObserverChange: function(msg) {
+    let observer = this._observers.get(msg.target);
+    if (msg.name === "child-process-shutdown") {
+      // If we didn't have any observers for this child process, don't do
+      // anything.
+      if (!observer)
+        return;
+
+      for (let i of observer._names) {
+        this._cps2.removeObserverForName(i, observer);
+      }
+
+      this._observers.delete(msg.target);
+      return;
+    }
+
+    let prefName = msg.data.name;
+    if (msg.name === "ContentPrefs:AddObserverForName") {
+      // The child process is responsible for not adding multiple parent
+      // observers for the same name.
+      if (!observer) {
+        observer = {
+          onContentPrefSet: function(group, name, value, isPrivate) {
+            msg.target.sendAsyncMessage("ContentPrefs:NotifyObservers",
+                                        { name: name, callback: "onContentPrefSet",
+                                          args: [ group, name, value, isPrivate ] });
+          },
+
+          onContentPrefRemoved: function(group, name, isPrivate) {
+            msg.target.sendAsyncMessage("ContentPrefs:NotifyObservers",
+                                        { name: name, callback: "onContentPrefRemoved",
+                                          args: [ group, name, isPrivate ] });
+          },
+
+          // The names we're using this observer object for, used to keep track
+          // of the number of names we care about as well as for removing this
+          // observer if its associated process goes away.
+          _names: new Set()
+        };
+
+        this._observers.set(msg.target, observer);
+      }
+
+      observer._names.add(prefName);
+
+      this._cps2.addObserverForName(prefName, observer);
+    } else {
+      // RemoveObserverForName
+
+      // We must have an observer.
+      this._cps2.removeObserverForName(prefName, observer);
+
+      observer._names.delete(prefName);
+      if (observer._names.size === 0) {
+        // This was the last use for this observer.
+        this._observers.delete(msg.target);
+      }
+    }
+  },
+
+  receiveMessage: function(msg) {
+    let data = msg.data;
+
+    if (!_methodsCallableFromChild.some(([method, args]) => method == data.call)) {
+      throw new Error(`Can't call ${data.call} from child!`);
+    }
+
+    let args = data.args;
+    let requestId = data.requestId;
+
+    let listener = {
+      handleResult: function(pref) {
+        msg.target.sendAsyncMessage("ContentPrefs:HandleResult",
+                                    { requestId: requestId,
+                                      contentPref: {
+                                        domain: pref.domain,
+                                        name: pref.name,
+                                        value: pref.value
+                                      }
+                                    });
+      },
+
+      handleError: function(error) {
+        msg.target.sendAsyncMessage("ContentPrefs:HandleError",
+                                    { requestId: requestId,
+                                      error: error });
+      },
+      handleCompletion: function(reason) {
+        msg.target.sendAsyncMessage("ContentPrefs:HandleCompletion",
+                                    { requestId: requestId,
+                                      reason: reason });
+      }
+    };
+
+    // Push our special listener.
+    args.push(listener);
+
+    // And call the function.
+    this._cps2[data.call](...args);
+  }
+};