tor-browser

The Tor Browser
git clone https://git.dasho.dev/tor-browser.git
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ObserverForwarder.sys.mjs (3188B)

      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
      3 * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
      4 
      5 import { AppConstants } from "resource://gre/modules/AppConstants.sys.mjs";
      6 
      7 // Because of the indirection with which we call into these modules, eslint
      8 // does not realize which of these modules are used, so we have to disable
      9 // the relevant lint rule. However, this does mean that when modifying the
     10 // list of observers or the modules they are associated with, you must be
     11 // more careful to ensure we remove unused modules.
     12 /* eslint-disable mozilla/valid-lazy */
     13 let lazy = {};
     14 ChromeUtils.defineESModuleGetters(lazy, {
     15  CanvasPermissionPromptHelper:
     16    "moz-src:///browser/modules/CanvasPermissionPromptHelper.sys.mjs",
     17  FilePickerCrashed: "resource:///modules/FilePickerCrashed.sys.mjs",
     18  PluginManager: "resource:///actors/PluginParent.sys.mjs",
     19  UnexpectedScriptObserver:
     20    "moz-src:///browser/modules/UnexpectedScriptObserver.sys.mjs",
     21  WebAuthnPromptHelper:
     22    "moz-src:///browser/modules/WebAuthnPromptHelper.sys.mjs",
     23 });
     24 
     25 // Map from observer topic to a list of exported objects whose observe()
     26 // method should be called when the topic is fired. The exported objects
     27 // are expected to be defined in the modules imported above.
     28 let gObservers = {
     29  "canvas-permissions-prompt": ["CanvasPermissionPromptHelper"],
     30  "canvas-permissions-prompt-hide-doorhanger": ["CanvasPermissionPromptHelper"],
     31 
     32  "UnexpectedJavaScriptLoad-Live": ["UnexpectedScriptObserver"],
     33  "UnexpectedJavaScriptLoad-UserTookAction": ["UnexpectedScriptObserver"],
     34 
     35  "file-picker-crashed": ["FilePickerCrashed"],
     36  "gmp-plugin-crash": ["PluginManager"],
     37  "plugin-crashed": ["PluginManager"],
     38 
     39  "webauthn-prompt": ["WebAuthnPromptHelper"],
     40 };
     41 if (Cu.isInAutomation) {
     42  gObservers["UnexpectedJavaScriptLoad-ResetNotification"] = [
     43    "UnexpectedScriptObserver",
     44  ];
     45 }
     46 
     47 if (AppConstants.MOZ_UPDATER) {
     48  ChromeUtils.defineESModuleGetters(lazy, {
     49    UpdateListener: "resource://gre/modules/UpdateListener.sys.mjs",
     50  });
     51 
     52  gObservers["update-downloading"] = ["UpdateListener"];
     53  gObservers["update-staged"] = ["UpdateListener"];
     54  gObservers["update-downloaded"] = ["UpdateListener"];
     55  gObservers["update-available"] = ["UpdateListener"];
     56  gObservers["update-error"] = ["UpdateListener"];
     57  gObservers["update-swap"] = ["UpdateListener"];
     58 }
     59 
     60 /**
     61 * Utility to avoid eagerly loading modules that are only needed
     62 * once a given observer topic is fired. Note that in an ideal world,
     63 * these observers would be added in parts of the same component that
     64 * are already loaded at startup, but not all components have such code.
     65 *
     66 * This module exists to avoid each component having to reinvent that wheel.
     67 */
     68 export const ObserverForwarder = {
     69  init() {
     70    for (const topic of Object.keys(gObservers)) {
     71      Services.obs.addObserver(this, topic);
     72    }
     73  },
     74 
     75  observe(subject, topic, data) {
     76    for (let objectName of gObservers[topic]) {
     77      try {
     78        lazy[objectName].observe(subject, topic, data);
     79      } catch (e) {
     80        console.error(e);
     81      }
     82    }
     83  },
     84 };