The Tor Browser: netwerk/protocol/http/UserAgentUpdates.jsm@6474c204b198 (annotated)

netwerk/protocol/http/UserAgentUpdates.jsm@6474c204b198 (annotated)

netwerk/protocol/http/UserAgentUpdates.jsm

Wed, 31 Dec 2014 06:09:35 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Wed, 31 Dec 2014 06:09:35 +0100
changeset 0: 6474c204b198
permissions: -rw-r--r--

Cloned upstream origin tor-browser at tor-browser-31.3.0esr-4.5-1-build1
revision ID fc1c9ff7c1b2defdbc039f12214767608f46423f for hacking purpose.

 /* 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 = ["UserAgentUpdates"];
 const Ci = Components.interfaces;
 const Cc = Components.classes;
 const Cu = Components.utils;
 Cu.import("resource://gre/modules/Services.jsm");
 Cu.import("resource://gre/modules/XPCOMUtils.jsm");
 XPCOMUtils.defineLazyModuleGetter(
   this, "FileUtils", "resource://gre/modules/FileUtils.jsm");
 XPCOMUtils.defineLazyModuleGetter(
   this, "OS", "resource://gre/modules/osfile.jsm");
 XPCOMUtils.defineLazyModuleGetter(
   this, "UpdateChannel", "resource://gre/modules/UpdateChannel.jsm");
 XPCOMUtils.defineLazyServiceGetter(
   this, "gUpdateTimer", "@mozilla.org/updates/timer-manager;1", "nsIUpdateTimerManager");
 XPCOMUtils.defineLazyGetter(this, "gApp",
   function() Cc["@mozilla.org/xre/app-info;1"]
     .getService(Ci.nsIXULAppInfo).QueryInterface(Ci.nsIXULRuntime)
 );
 XPCOMUtils.defineLazyGetter(this, "gDecoder",
   function() new TextDecoder()
 );
 XPCOMUtils.defineLazyGetter(this, "gEncoder",
   function() new TextEncoder()
 );
 const TIMER_ID = "user-agent-updates-timer";
 const PREF_UPDATES = "general.useragent.updates.";
 const PREF_UPDATES_ENABLED = PREF_UPDATES + "enabled";
 const PREF_UPDATES_URL = PREF_UPDATES + "url";
 const PREF_UPDATES_INTERVAL = PREF_UPDATES + "interval";
 const PREF_UPDATES_RETRY = PREF_UPDATES + "retry";
 const PREF_UPDATES_TIMEOUT = PREF_UPDATES + "timeout";
 const PREF_UPDATES_LASTUPDATED = PREF_UPDATES + "lastupdated";
 const KEY_PREFDIR = "PrefD";
 const KEY_APPDIR = "XCurProcD";
 const FILE_UPDATES = "ua-update.json";
 const PREF_APP_DISTRIBUTION = "distribution.id";
 const PREF_APP_DISTRIBUTION_VERSION = "distribution.version";
 var gInitialized = false;
 this.UserAgentUpdates = {
   init: function(callback) {
     if (gInitialized) {
       return;
     }
     gInitialized = true;
     this._callback = callback;
     this._lastUpdated = 0;
     this._applySavedUpdate();
     Services.prefs.addObserver(PREF_UPDATES, this, false);
   },
   uninit: function() {
     if (!gInitialized) {
       return;
     }
     gInitialized = false;
     Services.prefs.removeObserver(PREF_UPDATES, this);
   },
   _applyUpdate: function(update) {
     // Check pref again in case it has changed
     if (update && this._getPref(PREF_UPDATES_ENABLED, false)) {
       this._callback(update);
     } else {
       this._callback(null);
     }
   },
   _applySavedUpdate: function() {
     if (!this._getPref(PREF_UPDATES_ENABLED, false)) {
       // remove previous overrides
       this._applyUpdate(null);
       return;
     }
     // try loading from profile dir, then from app dir
     let dirs = [KEY_PREFDIR, KEY_APPDIR];
     dirs.reduce((prevLoad, dir) => {
       let file = FileUtils.getFile(dir, [FILE_UPDATES], true).path;
       // tryNext returns promise to read file under dir and parse it
       let tryNext = () => OS.File.read(file).then(
         (bytes) => {
           let update = JSON.parse(gDecoder.decode(bytes));
           if (!update) {
             throw new Error("invalid update");
           }
           return update;
         }
       );
       // try to load next one if the previous load failed
       return prevLoad ? prevLoad.then(null, tryNext) : tryNext();
     }, null).then(
       // apply update if loading was successful
       (update) => this._applyUpdate(update)
     );
     this._scheduleUpdate();
   },
   _saveToFile: function(update) {
     let file = FileUtils.getFile(KEY_PREFDIR, [FILE_UPDATES], true);
     let path = file.path;
     let bytes = gEncoder.encode(JSON.stringify(update));
     OS.File.writeAtomic(path, bytes, {tmpPath: path + ".tmp"}).then(
       () => {
         this._lastUpdated = Date.now();
         Services.prefs.setCharPref(
           PREF_UPDATES_LASTUPDATED, this._lastUpdated.toString());
       },
       Cu.reportError
     );
   },
   _getPref: function(name, def) {
     try {
       switch (typeof def) {
         case "number": return Services.prefs.getIntPref(name);
         case "boolean": return Services.prefs.getBoolPref(name);
       }
       return Services.prefs.getCharPref(name);
     } catch (e) {
       return def;
     }
   },
   _getParameters: function() ({
     "%DATE%": function() Date.now().toString(),
     "%PRODUCT%": function() gApp.name,
     "%APP_ID%": function() gApp.ID,
     "%APP_VERSION%": function() gApp.version,
     "%BUILD_ID%": function() gApp.appBuildID,
     "%OS%": function() gApp.OS,
     "%CHANNEL%": function() UpdateChannel.get(),
     "%DISTRIBUTION%": function() this._getPref(PREF_APP_DISTRIBUTION, ""),
     "%DISTRIBUTION_VERSION%": function() this._getPref(PREF_APP_DISTRIBUTION_VERSION, ""),
   }),
   _getUpdateURL: function() {
     let url = this._getPref(PREF_UPDATES_URL, "");
     let params = this._getParameters();
     return url.replace(/%[A-Z_]+%/g, function(match) {
       let param = params[match];
       // preserve the %FOO% string (e.g. as an encoding) if it's not a valid parameter
       return param ? encodeURIComponent(param()) : match;
     });
   },
   _fetchUpdate: function(url, success, error) {
     let request = Cc["@mozilla.org/xmlextras/xmlhttprequest;1"]
                     .createInstance(Ci.nsIXMLHttpRequest);
     request.mozBackgroundRequest = true;
     request.timeout = this._getPref(PREF_UPDATES_TIMEOUT, 60000);
     request.open("GET", url, true);
     request.overrideMimeType("application/json");
     request.responseType = "json";
     request.addEventListener("load", function() {
       let response = request.response;
       response ? success(response) : error();
     });
     request.addEventListener("error", error);
     request.send();
   },
   _update: function() {
     let url = this._getUpdateURL();
     url && this._fetchUpdate(url,
       (function(response) { // success
         // apply update and save overrides to profile
         this._applyUpdate(response);
         this._saveToFile(response);
         this._scheduleUpdate(); // cancel any retries
       }).bind(this),
       (function(response) { // error
         this._scheduleUpdate(true /* retry */);
       }).bind(this));
   },
   _scheduleUpdate: function(retry) {
     // only schedule updates in the main process
     if (gApp.processType !== Ci.nsIXULRuntime.PROCESS_TYPE_DEFAULT) {
       return;
     }
     let interval = this._getPref(PREF_UPDATES_INTERVAL, 604800 /* 1 week */);
     if (retry) {
       interval = this._getPref(PREF_UPDATES_RETRY, interval);
     }
     gUpdateTimer.registerTimer(TIMER_ID, this, Math.max(1, interval));
   },
   notify: function(timer) {
     // timer notification
     if (this._getPref(PREF_UPDATES_ENABLED, false)) {
       this._update();
     }
   },
   observe: function(subject, topic, data) {
     switch (topic) {
       case "nsPref:changed":
         if (data === PREF_UPDATES_ENABLED) {
           this._applySavedUpdate();
         } else if (data === PREF_UPDATES_INTERVAL) {
           this._scheduleUpdate();
         } else if (data === PREF_UPDATES_LASTUPDATED) {
           // reload from file if there has been an update
           let lastUpdated = parseInt(
             this._getPref(PREF_UPDATES_LASTUPDATED, "0"), 0);
           if (lastUpdated > this._lastUpdated) {
             this._applySavedUpdate();
             this._lastUpdated = lastUpdated;
           }
         }
         break;
     }
   },
   QueryInterface: XPCOMUtils.generateQI([
     Ci.nsIObserver,
     Ci.nsITimerCallback,
   ]),
 };

The Tor Browser / annotate

netwerk/protocol/http/UserAgentUpdates.jsm@6474c204b198 (annotated)

netwerk/protocol/http/UserAgentUpdates.jsm