Bug 903398 - [Session Restore] Use a 'cookie-changed' observer instead of asking the cookie service for every host; r=yoric

browser/components/sessionstore/src/SessionCookies.jsm

@@ -0,0 +1,249 @@
+/* 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 = ["SessionCookies"];
+
+const Cu = Components.utils;
+const Ci = Components.interfaces;
+
+Cu.import("resource://gre/modules/Services.jsm", this);
+
+// MAX_EXPIRY should be 2^63-1, but JavaScript can't handle that precision.
+const MAX_EXPIRY = Math.pow(2, 62);
+
+
+/**
+ * The external API implemented by the SessionCookies module.
+ */
+this.SessionCookies = Object.freeze({
+  getCookiesForHost: function (host) {
+    return SessionCookiesInternal.getCookiesForHost(host);
+  }
+});
+
+/**
+ * The internal API.
+ */
+let SessionCookiesInternal = {
+  /**
+   * Stores whether we're initialized, yet.
+   */
+  _initialized: false,
+
+  /**
+   * Returns the list of active session cookies for a given host.
+   */
+  getCookiesForHost: function (host) {
+    this._ensureInitialized();
+    return CookieStore.getCookiesForHost(host);
+  },
+
+  /**
+   * Handles observers notifications that are sent whenever cookies are added,
+   * changed, or removed. Ensures that the storage is updated accordingly.
+   */
+  observe: function (subject, topic, data) {
+    switch (data) {
+      case "added":
+      case "changed":
+        this._updateCookie(subject);
+        break;
+      case "deleted":
+        this._removeCookie(subject);
+        break;
+      case "cleared":
+        CookieStore.clear();
+        break;
+      case "batch-deleted":
+        this._removeCookies(subject);
+        break;
+      case "reload":
+        CookieStore.clear();
+        this._reloadCookies();
+        break;
+      default:
+        throw new Error("Unhandled cookie-changed notification.");
+    }
+  },
+
+  /**
+   * If called for the first time in a session, iterates all cookies in the
+   * cookies service and puts them into the store if they're session cookies.
+   */
+  _ensureInitialized: function () {
+    if (!this._initialized) {
+      this._reloadCookies();
+      this._initialized = true;
+      Services.obs.addObserver(this, "cookie-changed", false);
+    }
+  },
+
+  /**
+   * Updates or adds a given cookie to the store.
+   */
+  _updateCookie: function (cookie) {
+    cookie.QueryInterface(Ci.nsICookie2);
+
+    if (cookie.isSession) {
+      CookieStore.set(cookie);
+    }
+  },
+
+  /**
+   * Removes a given cookie from the store.
+   */
+  _removeCookie: function (cookie) {
+    cookie.QueryInterface(Ci.nsICookie2);
+
+    if (cookie.isSession) {
+      CookieStore.delete(cookie);
+    }
+  },
+
+  /**
+   * Removes a given list of cookies from the store.
+   */
+  _removeCookies: function (cookies) {
+    for (let i = 0; i < cookies.length; i++) {
+      this._removeCookie(cookies.queryElementAt(i, Ci.nsICookie2));
+    }
+  },
+
+  /**
+   * Iterates all cookies in the cookies service and puts them into the store
+   * if they're session cookies.
+   */
+  _reloadCookies: function () {
+    let iter = Services.cookies.enumerator;
+    while (iter.hasMoreElements()) {
+      this._updateCookie(iter.getNext());
+    }
+  }
+};
+
+/**
+ * The internal cookie storage that keeps track of every active session cookie.
+ * These are stored using maps per host, path, and cookie name.
+ */
+let CookieStore = {
+  /**
+   * The internal structure holding all known cookies.
+   *
+   * Host =>
+   *  Path =>
+   *    Name => {path: "/", name: "sessionid", secure: true}
+   *
+   * Maps are used for storage but the data structure is equivalent to this:
+   *
+   * this._hosts = {
+   *   "www.mozilla.org": {
+   *     "/": {
+   *       "username": {name: "username", value: "my_name_is", etc...},
+   *       "sessionid": {name: "sessionid", value: "1fdb3a", etc...}
+   *     }
+   *   },
+   *   "tbpl.mozilla.org": {
+   *     "/path": {
+   *       "cookiename": {name: "cookiename", value: "value", etc...}
+   *     }
+   *   }
+   * };
+   */
+  _hosts: new Map(),
+
+  /**
+   * Returns the list of stored session cookies for a given host.
+   *
+   * @param host
+   *        A string containing the host name we want to get cookies for.
+   */
+  getCookiesForHost: function (host) {
+    if (!this._hosts.has(host)) {
+      return [];
+    }
+
+    let cookies = [];
+
+    for (let pathToNamesMap of this._hosts.get(host).values()) {
+      cookies = cookies.concat([cookie for (cookie of pathToNamesMap.values())]);
+    }
+
+    return cookies;
+  },
+
+  /**
+   * Stores a given cookie.
+   *
+   * @param cookie
+   *        The nsICookie2 object to add to the storage.
+   */
+  set: function (cookie) {
+    let jscookie = {host: cookie.host, value: cookie.value};
+
+    // Only add properties with non-default values to save a few bytes.
+    if (cookie.path) {
+      jscookie.path = cookie.path;
+    }
+
+    if (cookie.name) {
+      jscookie.name = cookie.name;
+    }
+
+    if (cookie.isSecure) {
+      jscookie.secure = true;
+    }
+
+    if (cookie.isHttpOnly) {
+      jscookie.httponly = true;
+    }
+
+    if (cookie.expiry < MAX_EXPIRY) {
+      jscookie.expiry = cookie.expiry;
+    }
+
+    this._ensureMap(cookie).set(cookie.name, jscookie);
+  },
+
+  /**
+   * Removes a given cookie.
+   *
+   * @param cookie
+   *        The nsICookie2 object to be removed from storage.
+   */
+  delete: function (cookie) {
+    this._ensureMap(cookie).delete(cookie.name);
+  },
+
+  /**
+   * Removes all cookies.
+   */
+  clear: function () {
+    this._hosts.clear();
+  },
+
+  /**
+   * Creates all maps necessary to store a given cookie.
+   *
+   * @param cookie
+   *        The nsICookie2 object to create maps for.
+   *
+   * @return The newly created Map instance mapping cookie names to
+   *         internal jscookies, in the given path of the given host.
+   */
+  _ensureMap: function (cookie) {
+    if (!this._hosts.has(cookie.host)) {
+      this._hosts.set(cookie.host, new Map());
+    }
+
+    let pathToNamesMap = this._hosts.get(cookie.host);
+
+    if (!pathToNamesMap.has(cookie.path)) {
+      pathToNamesMap.set(cookie.path, new Map());
+    }
+
+    return pathToNamesMap.get(cookie.path);
+  }
+};

browser/components/sessionstore/src/SessionStore.jsm

@@ -120,6 +120,8 @@ XPCOMUtils.defineLazyModuleGetter(this, "DocumentUtils",
   "resource:///modules/sessionstore/DocumentUtils.jsm");
 XPCOMUtils.defineLazyModuleGetter(this, "SessionStorage",
   "resource:///modules/sessionstore/SessionStorage.jsm");
+XPCOMUtils.defineLazyModuleGetter(this, "SessionCookies",
+  "resource:///modules/sessionstore/SessionCookies.jsm");
 XPCOMUtils.defineLazyModuleGetter(this, "_SessionFile",
   "resource:///modules/sessionstore/_SessionFile.jsm");
 
@@ -2402,21 +2404,6 @@ let SessionStoreInternal = {
    *        { tabs: [ ... ], etc. }
    */
   _updateCookies: function ssi_updateCookies(aWindows) {
-    function addCookieToHash(aHash, aHost, aPath, aName, aCookie) {
-      // lazily build up a 3-dimensional hash, with
-      // aHost, aPath, and aName as keys
-      if (!aHash[aHost])
-        aHash[aHost] = {};
-      if (!aHash[aHost][aPath])
-        aHash[aHost][aPath] = {};
-      aHash[aHost][aPath][aName] = aCookie;
-    }
-
-    var jscookies = {};
-    var _this = this;
-    // MAX_EXPIRY should be 2^63-1, but JavaScript can't handle that precision
-    var MAX_EXPIRY = Math.pow(2, 62);
-
     for (let window of aWindows) {
       window.cookies = [];
 
@@ -2429,35 +2416,12 @@ let SessionStoreInternal = {
       }, this);
 
       for (var [host, isPinned] in Iterator(hosts)) {
-        let list;
-        try {
-          list = Services.cookies.getCookiesFromHost(host);
-        }
-        catch (ex) {
-          debug("getCookiesFromHost failed. Host: " + host);
-        }
-        while (list && list.hasMoreElements()) {
-          var cookie = list.getNext().QueryInterface(Ci.nsICookie2);
+        for (let cookie of SessionCookies.getCookiesForHost(host)) {
           // window._hosts will only have hosts with the right privacy rules,
           // so there is no need to do anything special with this call to
           // checkPrivacyLevel.
-          if (cookie.isSession && _this.checkPrivacyLevel(cookie.isSecure, isPinned)) {
-            // use the cookie's host, path, and name as keys into a hash,
-            // to make sure we serialize each cookie only once
-            if (!(cookie.host in jscookies &&
-                  cookie.path in jscookies[cookie.host] &&
-                  cookie.name in jscookies[cookie.host][cookie.path])) {
-              var jscookie = { "host": cookie.host, "value": cookie.value };
-              // only add attributes with non-default values (saving a few bits)
-              if (cookie.path) jscookie.path = cookie.path;
-              if (cookie.name) jscookie.name = cookie.name;
-              if (cookie.isSecure) jscookie.secure = true;
-              if (cookie.isHttpOnly) jscookie.httponly = true;
-              if (cookie.expiry < MAX_EXPIRY) jscookie.expiry = cookie.expiry;
-
-              addCookieToHash(jscookies, cookie.host, cookie.path, cookie.name, jscookie);
-            }
-            window.cookies.push(jscookies[cookie.host][cookie.path][cookie.name]);
+          if (this.checkPrivacyLevel(cookie.secure, isPinned)) {
+            window.cookies.push(cookie);
           }
         }
       }

browser/components/sessionstore/src/moz.build

@@ -14,6 +14,7 @@ JS_MODULES_PATH = 'modules/sessionstore'
 
 EXTRA_JS_MODULES = [
     'DocumentUtils.jsm',
+    'SessionCookies.jsm',
     'SessionMigration.jsm',
     'SessionStorage.jsm',
     'SessionWorker.js',