b2g/components/KillSwitch.js

   1 /* This Source Code Form is subject to the terms of the Mozilla Public
   2  * License, v. 2.0. If a copy of the MPL was not distributed with this file,
   3  * You can obtain one at http://mozilla.org/MPL/2.0/. */
   4
   5 "use strict";
   6
   7 const DEBUG = false;
   8
   9 function debug(s) {
  10   dump("-*- KillSwitch.js: " + s + "\n");
  11 }
  12
  13 const {interfaces: Ci, utils: Cu} = Components;
  14
  15 Cu.import("resource://gre/modules/XPCOMUtils.jsm");
  16 Cu.import("resource://gre/modules/DOMRequestHelper.jsm");
  17
  18 XPCOMUtils.defineLazyModuleGetter(this, "Services",
  19                                   "resource://gre/modules/Services.jsm");
  20
  21 XPCOMUtils.defineLazyServiceGetter(this, "cpmm",
  22                                    "@mozilla.org/childprocessmessagemanager;1",
  23                                    "nsIMessageSender");
  24
  25 const KILLSWITCH_CID = "{b6eae5c6-971c-4772-89e5-5df626bf3f09}";
  26 const KILLSWITCH_CONTRACTID = "@mozilla.org/moz-kill-switch;1";
  27
  28 const kEnableKillSwitch   = "KillSwitch:Enable";
  29 const kEnableKillSwitchOK = "KillSwitch:Enable:OK";
  30 const kEnableKillSwitchKO = "KillSwitch:Enable:KO";
  31
  32 const kDisableKillSwitch   = "KillSwitch:Disable";
  33 const kDisableKillSwitchOK = "KillSwitch:Disable:OK";
  34 const kDisableKillSwitchKO = "KillSwitch:Disable:KO";
  35
  36 function KillSwitch() {
  37   this._window       = null;
  38 }
  39
  40 KillSwitch.prototype = {
  41
  42   __proto__: DOMRequestIpcHelper.prototype,
  43
  44   init: function(aWindow) {
  45     DEBUG && debug("init");
  46     this._window = aWindow;
  47     this.initDOMRequestHelper(this._window);
  48   },
  49
  50   enable: function() {
  51     DEBUG && debug("KillSwitch: enable");
  52
  53     cpmm.addMessageListener(kEnableKillSwitchOK, this);
  54     cpmm.addMessageListener(kEnableKillSwitchKO, this);
  55     return this.createPromise((aResolve, aReject) => {
  56       cpmm.sendAsyncMessage(kEnableKillSwitch, {
  57         requestID: this.getPromiseResolverId({
  58           resolve: aResolve,
  59           reject: aReject
  60         })
  61       });
  62     });
  63   },
  64
  65   disable: function() {
  66     DEBUG && debug("KillSwitch: disable");
  67
  68     cpmm.addMessageListener(kDisableKillSwitchOK, this);
  69     cpmm.addMessageListener(kDisableKillSwitchKO, this);
  70     return this.createPromise((aResolve, aReject) => {
  71       cpmm.sendAsyncMessage(kDisableKillSwitch, {
  72         requestID: this.getPromiseResolverId({
  73           resolve: aResolve,
  74           reject: aReject
  75         })
  76       });
  77     });
  78   },
  79
  80   receiveMessage: function(message) {
  81     DEBUG && debug("Received: " + message.name);
  82
  83     cpmm.removeMessageListener(kEnableKillSwitchOK, this);
  84     cpmm.removeMessageListener(kEnableKillSwitchKO, this);
  85     cpmm.removeMessageListener(kDisableKillSwitchOK, this);
  86     cpmm.removeMessageListener(kDisableKillSwitchKO, this);
  87
  88     let req = this.takePromiseResolver(message.data.requestID);
  89
  90     switch (message.name) {
  91       case kEnableKillSwitchKO:
  92       case kDisableKillSwitchKO:
  93         req.reject(false);
  94         break;
  95
  96       case kEnableKillSwitchOK:
  97       case kDisableKillSwitchOK:
  98         req.resolve(true);
  99         break;
 100
 101       default:
 102         DEBUG && debug("Unrecognized message: " + message.name);
 103         break;
 104     }
 105   },
 106
 107   classID : Components.ID(KILLSWITCH_CID),
 108   contractID : KILLSWITCH_CONTRACTID,
 109   QueryInterface: XPCOMUtils.generateQI([Ci.nsIKillSwitch,
 110                                          Ci.nsIDOMGlobalPropertyInitializer,
 111                                          Ci.nsIObserver,
 112                                          Ci.nsIMessageListener,
 113                                          Ci.nsISupportsWeakReference]),
 114 };
 115
 116 this.NSGetFactory = XPCOMUtils.generateNSGetFactory([KillSwitch]);