1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/browser/components/sessionstore/content/content-sessionStore.js Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,725 @@
1.4 +/* This Source Code Form is subject to the terms of the Mozilla Public
1.5 + * License, v. 2.0. If a copy of the MPL was not distributed with this
1.6 + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
1.7 +
1.8 +"use strict";
1.9 +
1.10 +function debug(msg) {
1.11 + Services.console.logStringMessage("SessionStoreContent: " + msg);
1.12 +}
1.13 +
1.14 +let Cu = Components.utils;
1.15 +let Cc = Components.classes;
1.16 +let Ci = Components.interfaces;
1.17 +let Cr = Components.results;
1.18 +
1.19 +Cu.import("resource://gre/modules/XPCOMUtils.jsm", this);
1.20 +Cu.import("resource://gre/modules/Timer.jsm", this);
1.21 +
1.22 +XPCOMUtils.defineLazyModuleGetter(this, "DocShellCapabilities",
1.23 + "resource:///modules/sessionstore/DocShellCapabilities.jsm");
1.24 +XPCOMUtils.defineLazyModuleGetter(this, "FormData",
1.25 + "resource://gre/modules/FormData.jsm");
1.26 +XPCOMUtils.defineLazyModuleGetter(this, "PageStyle",
1.27 + "resource:///modules/sessionstore/PageStyle.jsm");
1.28 +XPCOMUtils.defineLazyModuleGetter(this, "ScrollPosition",
1.29 + "resource://gre/modules/ScrollPosition.jsm");
1.30 +XPCOMUtils.defineLazyModuleGetter(this, "SessionHistory",
1.31 + "resource:///modules/sessionstore/SessionHistory.jsm");
1.32 +XPCOMUtils.defineLazyModuleGetter(this, "SessionStorage",
1.33 + "resource:///modules/sessionstore/SessionStorage.jsm");
1.34 +
1.35 +Cu.import("resource:///modules/sessionstore/FrameTree.jsm", this);
1.36 +let gFrameTree = new FrameTree(this);
1.37 +
1.38 +Cu.import("resource:///modules/sessionstore/ContentRestore.jsm", this);
1.39 +XPCOMUtils.defineLazyGetter(this, 'gContentRestore',
1.40 + () => { return new ContentRestore(this) });
1.41 +
1.42 +/**
1.43 + * Returns a lazy function that will evaluate the given
1.44 + * function |fn| only once and cache its return value.
1.45 + */
1.46 +function createLazy(fn) {
1.47 + let cached = false;
1.48 + let cachedValue = null;
1.49 +
1.50 + return function lazy() {
1.51 + if (!cached) {
1.52 + cachedValue = fn();
1.53 + cached = true;
1.54 + }
1.55 +
1.56 + return cachedValue;
1.57 + };
1.58 +}
1.59 +
1.60 +/**
1.61 + * Determines whether the given storage event was triggered by changes
1.62 + * to the sessionStorage object and not the local or globalStorage.
1.63 + */
1.64 +function isSessionStorageEvent(event) {
1.65 + try {
1.66 + return event.storageArea == content.sessionStorage;
1.67 + } catch (ex if ex instanceof Ci.nsIException && ex.result == Cr.NS_ERROR_NOT_AVAILABLE) {
1.68 + // This page does not have a DOMSessionStorage
1.69 + // (this is typically the case for about: pages)
1.70 + return false;
1.71 + }
1.72 +}
1.73 +
1.74 +/**
1.75 + * Listens for and handles content events that we need for the
1.76 + * session store service to be notified of state changes in content.
1.77 + */
1.78 +let EventListener = {
1.79 +
1.80 + init: function () {
1.81 + addEventListener("load", this, true);
1.82 + },
1.83 +
1.84 + handleEvent: function (event) {
1.85 + // Ignore load events from subframes.
1.86 + if (event.target != content.document) {
1.87 + return;
1.88 + }
1.89 +
1.90 + // If we're in the process of restoring, this load may signal
1.91 + // the end of the restoration.
1.92 + let epoch = gContentRestore.getRestoreEpoch();
1.93 + if (!epoch) {
1.94 + return;
1.95 + }
1.96 +
1.97 + // Restore the form data and scroll position.
1.98 + gContentRestore.restoreDocument();
1.99 +
1.100 + // Ask SessionStore.jsm to trigger SSTabRestored.
1.101 + sendAsyncMessage("SessionStore:restoreDocumentComplete", {epoch: epoch});
1.102 + }
1.103 +};
1.104 +
1.105 +/**
1.106 + * Listens for and handles messages sent by the session store service.
1.107 + */
1.108 +let MessageListener = {
1.109 +
1.110 + MESSAGES: [
1.111 + "SessionStore:restoreHistory",
1.112 + "SessionStore:restoreTabContent",
1.113 + "SessionStore:resetRestore",
1.114 + ],
1.115 +
1.116 + init: function () {
1.117 + this.MESSAGES.forEach(m => addMessageListener(m, this));
1.118 + },
1.119 +
1.120 + receiveMessage: function ({name, data}) {
1.121 + switch (name) {
1.122 + case "SessionStore:restoreHistory":
1.123 + let reloadCallback = () => {
1.124 + // Inform SessionStore.jsm about the reload. It will send
1.125 + // restoreTabContent in response.
1.126 + sendAsyncMessage("SessionStore:reloadPendingTab", {epoch: data.epoch});
1.127 + };
1.128 + gContentRestore.restoreHistory(data.epoch, data.tabData, reloadCallback);
1.129 +
1.130 + // When restoreHistory finishes, we send a synchronous message to
1.131 + // SessionStore.jsm so that it can run SSTabRestoring. Users of
1.132 + // SSTabRestoring seem to get confused if chrome and content are out of
1.133 + // sync about the state of the restore (particularly regarding
1.134 + // docShell.currentURI). Using a synchronous message is the easiest way
1.135 + // to temporarily synchronize them.
1.136 + sendSyncMessage("SessionStore:restoreHistoryComplete", {epoch: data.epoch});
1.137 + break;
1.138 + case "SessionStore:restoreTabContent":
1.139 + let epoch = gContentRestore.getRestoreEpoch();
1.140 + let finishCallback = () => {
1.141 + // Tell SessionStore.jsm that it may want to restore some more tabs,
1.142 + // since it restores a max of MAX_CONCURRENT_TAB_RESTORES at a time.
1.143 + sendAsyncMessage("SessionStore:restoreTabContentComplete", {epoch: epoch});
1.144 + };
1.145 +
1.146 + // We need to pass the value of didStartLoad back to SessionStore.jsm.
1.147 + let didStartLoad = gContentRestore.restoreTabContent(finishCallback);
1.148 +
1.149 + sendAsyncMessage("SessionStore:restoreTabContentStarted", {epoch: epoch});
1.150 +
1.151 + if (!didStartLoad) {
1.152 + // Pretend that the load succeeded so that event handlers fire correctly.
1.153 + sendAsyncMessage("SessionStore:restoreTabContentComplete", {epoch: epoch});
1.154 + sendAsyncMessage("SessionStore:restoreDocumentComplete", {epoch: epoch});
1.155 + }
1.156 + break;
1.157 + case "SessionStore:resetRestore":
1.158 + gContentRestore.resetRestore();
1.159 + break;
1.160 + default:
1.161 + debug("received unknown message '" + name + "'");
1.162 + break;
1.163 + }
1.164 + }
1.165 +};
1.166 +
1.167 +/**
1.168 + * On initialization, this handler gets sent to the parent process as a CPOW.
1.169 + * The parent will use it only to flush pending data from the frame script
1.170 + * when needed, i.e. when closing a tab, closing a window, shutting down, etc.
1.171 + *
1.172 + * This will hopefully not be needed in the future once we have async APIs for
1.173 + * closing windows and tabs.
1.174 + */
1.175 +let SyncHandler = {
1.176 + init: function () {
1.177 + // Send this object as a CPOW to chrome. In single-process mode,
1.178 + // the synchronous send ensures that the handler object is
1.179 + // available in SessionStore.jsm immediately upon loading
1.180 + // content-sessionStore.js.
1.181 + sendSyncMessage("SessionStore:setupSyncHandler", {}, {handler: this});
1.182 + },
1.183 +
1.184 + /**
1.185 + * This function is used to make the tab process flush all data that
1.186 + * hasn't been sent to the parent process, yet.
1.187 + *
1.188 + * @param id (int)
1.189 + * A unique id that represents the last message received by the chrome
1.190 + * process before flushing. We will use this to determine data that
1.191 + * would be lost when data has been sent asynchronously shortly
1.192 + * before flushing synchronously.
1.193 + */
1.194 + flush: function (id) {
1.195 + MessageQueue.flush(id);
1.196 + },
1.197 +
1.198 + /**
1.199 + * DO NOT USE - DEBUGGING / TESTING ONLY
1.200 + *
1.201 + * This function is used to simulate certain situations where race conditions
1.202 + * can occur by sending data shortly before flushing synchronously.
1.203 + */
1.204 + flushAsync: function () {
1.205 + MessageQueue.flushAsync();
1.206 + }
1.207 +};
1.208 +
1.209 +/**
1.210 + * Listens for changes to the session history. Whenever the user navigates
1.211 + * we will collect URLs and everything belonging to session history.
1.212 + *
1.213 + * Causes a SessionStore:update message to be sent that contains the current
1.214 + * session history.
1.215 + *
1.216 + * Example:
1.217 + * {entries: [{url: "about:mozilla", ...}, ...], index: 1}
1.218 + */
1.219 +let SessionHistoryListener = {
1.220 + init: function () {
1.221 + // The frame tree observer is needed to handle navigating away from
1.222 + // an about page. Currently nsISHistoryListener does not have
1.223 + // OnHistoryNewEntry() called for about pages because the history entry is
1.224 + // modified to point at the new page. Once Bug 981900 lands the frame tree
1.225 + // observer can be removed.
1.226 + gFrameTree.addObserver(this);
1.227 +
1.228 + // By adding the SHistoryListener immediately, we will unfortunately be
1.229 + // notified of every history entry as the tab is restored. We don't bother
1.230 + // waiting to add the listener later because these notifications are cheap.
1.231 + // We will likely only collect once since we are batching collection on
1.232 + // a delay.
1.233 + docShell.QueryInterface(Ci.nsIWebNavigation).sessionHistory.
1.234 + addSHistoryListener(this);
1.235 +
1.236 + // Collect data if we start with a non-empty shistory.
1.237 + if (!SessionHistory.isEmpty(docShell)) {
1.238 + this.collect();
1.239 + }
1.240 + },
1.241 +
1.242 + uninit: function () {
1.243 + let sessionHistory = docShell.QueryInterface(Ci.nsIWebNavigation).sessionHistory;
1.244 + if (sessionHistory) {
1.245 + sessionHistory.removeSHistoryListener(this);
1.246 + }
1.247 + },
1.248 +
1.249 + collect: function () {
1.250 + if (docShell) {
1.251 + MessageQueue.push("history", () => SessionHistory.collect(docShell));
1.252 + }
1.253 + },
1.254 +
1.255 + onFrameTreeCollected: function () {
1.256 + this.collect();
1.257 + },
1.258 +
1.259 + onFrameTreeReset: function () {
1.260 + this.collect();
1.261 + },
1.262 +
1.263 + OnHistoryNewEntry: function (newURI) {
1.264 + this.collect();
1.265 + },
1.266 +
1.267 + OnHistoryGoBack: function (backURI) {
1.268 + this.collect();
1.269 + return true;
1.270 + },
1.271 +
1.272 + OnHistoryGoForward: function (forwardURI) {
1.273 + this.collect();
1.274 + return true;
1.275 + },
1.276 +
1.277 + OnHistoryGotoIndex: function (index, gotoURI) {
1.278 + this.collect();
1.279 + return true;
1.280 + },
1.281 +
1.282 + OnHistoryPurge: function (numEntries) {
1.283 + this.collect();
1.284 + return true;
1.285 + },
1.286 +
1.287 + OnHistoryReload: function (reloadURI, reloadFlags) {
1.288 + this.collect();
1.289 + return true;
1.290 + },
1.291 +
1.292 + OnHistoryReplaceEntry: function (index) {
1.293 + this.collect();
1.294 + },
1.295 +
1.296 + QueryInterface: XPCOMUtils.generateQI([
1.297 + Ci.nsISHistoryListener,
1.298 + Ci.nsISupportsWeakReference
1.299 + ])
1.300 +};
1.301 +
1.302 +/**
1.303 + * Listens for scroll position changes. Whenever the user scrolls the top-most
1.304 + * frame we update the scroll position and will restore it when requested.
1.305 + *
1.306 + * Causes a SessionStore:update message to be sent that contains the current
1.307 + * scroll positions as a tree of strings. If no frame of the whole frame tree
1.308 + * is scrolled this will return null so that we don't tack a property onto
1.309 + * the tabData object in the parent process.
1.310 + *
1.311 + * Example:
1.312 + * {scroll: "100,100", children: [null, null, {scroll: "200,200"}]}
1.313 + */
1.314 +let ScrollPositionListener = {
1.315 + init: function () {
1.316 + addEventListener("scroll", this);
1.317 + gFrameTree.addObserver(this);
1.318 + },
1.319 +
1.320 + handleEvent: function (event) {
1.321 + let frame = event.target && event.target.defaultView;
1.322 +
1.323 + // Don't collect scroll data for frames created at or after the load event
1.324 + // as SessionStore can't restore scroll data for those.
1.325 + if (frame && gFrameTree.contains(frame)) {
1.326 + MessageQueue.push("scroll", () => this.collect());
1.327 + }
1.328 + },
1.329 +
1.330 + onFrameTreeCollected: function () {
1.331 + MessageQueue.push("scroll", () => this.collect());
1.332 + },
1.333 +
1.334 + onFrameTreeReset: function () {
1.335 + MessageQueue.push("scroll", () => null);
1.336 + },
1.337 +
1.338 + collect: function () {
1.339 + return gFrameTree.map(ScrollPosition.collect);
1.340 + }
1.341 +};
1.342 +
1.343 +/**
1.344 + * Listens for changes to input elements. Whenever the value of an input
1.345 + * element changes we will re-collect data for the current frame tree and send
1.346 + * a message to the parent process.
1.347 + *
1.348 + * Causes a SessionStore:update message to be sent that contains the form data
1.349 + * for all reachable frames.
1.350 + *
1.351 + * Example:
1.352 + * {
1.353 + * formdata: {url: "http://mozilla.org/", id: {input_id: "input value"}},
1.354 + * children: [
1.355 + * null,
1.356 + * {url: "http://sub.mozilla.org/", id: {input_id: "input value 2"}}
1.357 + * ]
1.358 + * }
1.359 + */
1.360 +let FormDataListener = {
1.361 + init: function () {
1.362 + addEventListener("input", this, true);
1.363 + addEventListener("change", this, true);
1.364 + gFrameTree.addObserver(this);
1.365 + },
1.366 +
1.367 + handleEvent: function (event) {
1.368 + let frame = event.target &&
1.369 + event.target.ownerDocument &&
1.370 + event.target.ownerDocument.defaultView;
1.371 +
1.372 + // Don't collect form data for frames created at or after the load event
1.373 + // as SessionStore can't restore form data for those.
1.374 + if (frame && gFrameTree.contains(frame)) {
1.375 + MessageQueue.push("formdata", () => this.collect());
1.376 + }
1.377 + },
1.378 +
1.379 + onFrameTreeReset: function () {
1.380 + MessageQueue.push("formdata", () => null);
1.381 + },
1.382 +
1.383 + collect: function () {
1.384 + return gFrameTree.map(FormData.collect);
1.385 + }
1.386 +};
1.387 +
1.388 +/**
1.389 + * Listens for changes to the page style. Whenever a different page style is
1.390 + * selected or author styles are enabled/disabled we send a message with the
1.391 + * currently applied style to the chrome process.
1.392 + *
1.393 + * Causes a SessionStore:update message to be sent that contains the currently
1.394 + * selected pageStyle for all reachable frames.
1.395 + *
1.396 + * Example:
1.397 + * {pageStyle: "Dusk", children: [null, {pageStyle: "Mozilla"}]}
1.398 + */
1.399 +let PageStyleListener = {
1.400 + init: function () {
1.401 + Services.obs.addObserver(this, "author-style-disabled-changed", false);
1.402 + Services.obs.addObserver(this, "style-sheet-applicable-state-changed", false);
1.403 + gFrameTree.addObserver(this);
1.404 + },
1.405 +
1.406 + uninit: function () {
1.407 + Services.obs.removeObserver(this, "author-style-disabled-changed");
1.408 + Services.obs.removeObserver(this, "style-sheet-applicable-state-changed");
1.409 + },
1.410 +
1.411 + observe: function (subject, topic) {
1.412 + let frame = subject.defaultView;
1.413 +
1.414 + if (frame && gFrameTree.contains(frame)) {
1.415 + MessageQueue.push("pageStyle", () => this.collect());
1.416 + }
1.417 + },
1.418 +
1.419 + collect: function () {
1.420 + return PageStyle.collect(docShell, gFrameTree);
1.421 + },
1.422 +
1.423 + onFrameTreeCollected: function () {
1.424 + MessageQueue.push("pageStyle", () => this.collect());
1.425 + },
1.426 +
1.427 + onFrameTreeReset: function () {
1.428 + MessageQueue.push("pageStyle", () => null);
1.429 + }
1.430 +};
1.431 +
1.432 +/**
1.433 + * Listens for changes to docShell capabilities. Whenever a new load is started
1.434 + * we need to re-check the list of capabilities and send message when it has
1.435 + * changed.
1.436 + *
1.437 + * Causes a SessionStore:update message to be sent that contains the currently
1.438 + * disabled docShell capabilities (all nsIDocShell.allow* properties set to
1.439 + * false) as a string - i.e. capability names separate by commas.
1.440 + */
1.441 +let DocShellCapabilitiesListener = {
1.442 + /**
1.443 + * This field is used to compare the last docShell capabilities to the ones
1.444 + * that have just been collected. If nothing changed we won't send a message.
1.445 + */
1.446 + _latestCapabilities: "",
1.447 +
1.448 + init: function () {
1.449 + gFrameTree.addObserver(this);
1.450 + },
1.451 +
1.452 + /**
1.453 + * onFrameTreeReset() is called as soon as we start loading a page.
1.454 + */
1.455 + onFrameTreeReset: function() {
1.456 + // The order of docShell capabilities cannot change while we're running
1.457 + // so calling join() without sorting before is totally sufficient.
1.458 + let caps = DocShellCapabilities.collect(docShell).join(",");
1.459 +
1.460 + // Send new data only when the capability list changes.
1.461 + if (caps != this._latestCapabilities) {
1.462 + this._latestCapabilities = caps;
1.463 + MessageQueue.push("disallow", () => caps || null);
1.464 + }
1.465 + }
1.466 +};
1.467 +
1.468 +/**
1.469 + * Listens for changes to the DOMSessionStorage. Whenever new keys are added,
1.470 + * existing ones removed or changed, or the storage is cleared we will send a
1.471 + * message to the parent process containing up-to-date sessionStorage data.
1.472 + *
1.473 + * Causes a SessionStore:update message to be sent that contains the current
1.474 + * DOMSessionStorage contents. The data is a nested object using host names
1.475 + * as keys and per-host DOMSessionStorage data as values.
1.476 + */
1.477 +let SessionStorageListener = {
1.478 + init: function () {
1.479 + addEventListener("MozStorageChanged", this);
1.480 + Services.obs.addObserver(this, "browser:purge-domain-data", false);
1.481 + gFrameTree.addObserver(this);
1.482 + },
1.483 +
1.484 + uninit: function () {
1.485 + Services.obs.removeObserver(this, "browser:purge-domain-data");
1.486 + },
1.487 +
1.488 + handleEvent: function (event) {
1.489 + // Ignore events triggered by localStorage or globalStorage changes.
1.490 + if (gFrameTree.contains(event.target) && isSessionStorageEvent(event)) {
1.491 + this.collect();
1.492 + }
1.493 + },
1.494 +
1.495 + observe: function () {
1.496 + // Collect data on the next tick so that any other observer
1.497 + // that needs to purge data can do its work first.
1.498 + setTimeout(() => this.collect(), 0);
1.499 + },
1.500 +
1.501 + collect: function () {
1.502 + if (docShell) {
1.503 + MessageQueue.push("storage", () => SessionStorage.collect(docShell, gFrameTree));
1.504 + }
1.505 + },
1.506 +
1.507 + onFrameTreeCollected: function () {
1.508 + this.collect();
1.509 + },
1.510 +
1.511 + onFrameTreeReset: function () {
1.512 + this.collect();
1.513 + }
1.514 +};
1.515 +
1.516 +/**
1.517 + * Listen for changes to the privacy status of the tab.
1.518 + * By definition, tabs start in non-private mode.
1.519 + *
1.520 + * Causes a SessionStore:update message to be sent for
1.521 + * field "isPrivate". This message contains
1.522 + * |true| if the tab is now private
1.523 + * |null| if the tab is now public - the field is therefore
1.524 + * not saved.
1.525 + */
1.526 +let PrivacyListener = {
1.527 + init: function() {
1.528 + docShell.addWeakPrivacyTransitionObserver(this);
1.529 +
1.530 + // Check that value at startup as it might have
1.531 + // been set before the frame script was loaded.
1.532 + if (docShell.QueryInterface(Ci.nsILoadContext).usePrivateBrowsing) {
1.533 + MessageQueue.push("isPrivate", () => true);
1.534 + }
1.535 + },
1.536 +
1.537 + // Ci.nsIPrivacyTransitionObserver
1.538 + privateModeChanged: function(enabled) {
1.539 + MessageQueue.push("isPrivate", () => enabled || null);
1.540 + },
1.541 +
1.542 + QueryInterface: XPCOMUtils.generateQI([Ci.nsIPrivacyTransitionObserver,
1.543 + Ci.nsISupportsWeakReference])
1.544 +};
1.545 +
1.546 +/**
1.547 + * A message queue that takes collected data and will take care of sending it
1.548 + * to the chrome process. It allows flushing using synchronous messages and
1.549 + * takes care of any race conditions that might occur because of that. Changes
1.550 + * will be batched if they're pushed in quick succession to avoid a message
1.551 + * flood.
1.552 + */
1.553 +let MessageQueue = {
1.554 + /**
1.555 + * A unique, monotonically increasing ID used for outgoing messages. This is
1.556 + * important to make it possible to reuse tabs and allow sync flushes before
1.557 + * data could be destroyed.
1.558 + */
1.559 + _id: 1,
1.560 +
1.561 + /**
1.562 + * A map (string -> lazy fn) holding lazy closures of all queued data
1.563 + * collection routines. These functions will return data collected from the
1.564 + * docShell.
1.565 + */
1.566 + _data: new Map(),
1.567 +
1.568 + /**
1.569 + * A map holding the |this._id| value for every type of data back when it
1.570 + * was pushed onto the queue. We will use those IDs to find the data to send
1.571 + * and flush.
1.572 + */
1.573 + _lastUpdated: new Map(),
1.574 +
1.575 + /**
1.576 + * The delay (in ms) used to delay sending changes after data has been
1.577 + * invalidated.
1.578 + */
1.579 + BATCH_DELAY_MS: 1000,
1.580 +
1.581 + /**
1.582 + * The current timeout ID, null if there is no queue data. We use timeouts
1.583 + * to damp a flood of data changes and send lots of changes as one batch.
1.584 + */
1.585 + _timeout: null,
1.586 +
1.587 + /**
1.588 + * Pushes a given |value| onto the queue. The given |key| represents the type
1.589 + * of data that is stored and can override data that has been queued before
1.590 + * but has not been sent to the parent process, yet.
1.591 + *
1.592 + * @param key (string)
1.593 + * A unique identifier specific to the type of data this is passed.
1.594 + * @param fn (function)
1.595 + * A function that returns the value that will be sent to the parent
1.596 + * process.
1.597 + */
1.598 + push: function (key, fn) {
1.599 + this._data.set(key, createLazy(fn));
1.600 + this._lastUpdated.set(key, this._id);
1.601 +
1.602 + if (!this._timeout) {
1.603 + // Wait a little before sending the message to batch multiple changes.
1.604 + this._timeout = setTimeout(() => this.send(), this.BATCH_DELAY_MS);
1.605 + }
1.606 + },
1.607 +
1.608 + /**
1.609 + * Sends queued data to the chrome process.
1.610 + *
1.611 + * @param options (object)
1.612 + * {id: 123} to override the update ID used to accumulate data to send.
1.613 + * {sync: true} to send data to the parent process synchronously.
1.614 + */
1.615 + send: function (options = {}) {
1.616 + // Looks like we have been called off a timeout after the tab has been
1.617 + // closed. The docShell is gone now and we can just return here as there
1.618 + // is nothing to do.
1.619 + if (!docShell) {
1.620 + return;
1.621 + }
1.622 +
1.623 + if (this._timeout) {
1.624 + clearTimeout(this._timeout);
1.625 + this._timeout = null;
1.626 + }
1.627 +
1.628 + let sync = options && options.sync;
1.629 + let startID = (options && options.id) || this._id;
1.630 +
1.631 + // We use sendRpcMessage in the sync case because we may have been called
1.632 + // through a CPOW. RPC messages are the only synchronous messages that the
1.633 + // child is allowed to send to the parent while it is handling a CPOW
1.634 + // request.
1.635 + let sendMessage = sync ? sendRpcMessage : sendAsyncMessage;
1.636 +
1.637 + let durationMs = Date.now();
1.638 +
1.639 + let data = {};
1.640 + for (let [key, id] of this._lastUpdated) {
1.641 + // There is no data for the given key anymore because
1.642 + // the parent process already marked it as received.
1.643 + if (!this._data.has(key)) {
1.644 + continue;
1.645 + }
1.646 +
1.647 + if (startID > id) {
1.648 + // If the |id| passed by the parent process is higher than the one
1.649 + // stored in |_lastUpdated| for the given key we know that the parent
1.650 + // received all necessary data and we can remove it from the map.
1.651 + this._data.delete(key);
1.652 + continue;
1.653 + }
1.654 +
1.655 + data[key] = this._data.get(key)();
1.656 + }
1.657 +
1.658 + durationMs = Date.now() - durationMs;
1.659 + let telemetry = {
1.660 + FX_SESSION_RESTORE_CONTENT_COLLECT_DATA_LONGEST_OP_MS: durationMs
1.661 + }
1.662 +
1.663 + // Send all data to the parent process.
1.664 + sendMessage("SessionStore:update", {
1.665 + id: this._id,
1.666 + data: data,
1.667 + telemetry: telemetry
1.668 + });
1.669 +
1.670 + // Increase our unique message ID.
1.671 + this._id++;
1.672 + },
1.673 +
1.674 + /**
1.675 + * This function is used to make the message queue flush all queue data that
1.676 + * hasn't been sent to the parent process, yet.
1.677 + *
1.678 + * @param id (int)
1.679 + * A unique id that represents the latest message received by the
1.680 + * chrome process. We can use this to determine which messages have not
1.681 + * yet been received because they are still stuck in the event queue.
1.682 + */
1.683 + flush: function (id) {
1.684 + // It's important to always send data, even if there is nothing to flush.
1.685 + // The update message will be received by the parent process that can then
1.686 + // update its last received update ID to ignore stale messages.
1.687 + this.send({id: id + 1, sync: true});
1.688 +
1.689 + this._data.clear();
1.690 + this._lastUpdated.clear();
1.691 + },
1.692 +
1.693 + /**
1.694 + * DO NOT USE - DEBUGGING / TESTING ONLY
1.695 + *
1.696 + * This function is used to simulate certain situations where race conditions
1.697 + * can occur by sending data shortly before flushing synchronously.
1.698 + */
1.699 + flushAsync: function () {
1.700 + if (!Services.prefs.getBoolPref("browser.sessionstore.debug")) {
1.701 + throw new Error("flushAsync() must be used for testing, only.");
1.702 + }
1.703 +
1.704 + this.send();
1.705 + }
1.706 +};
1.707 +
1.708 +EventListener.init();
1.709 +MessageListener.init();
1.710 +FormDataListener.init();
1.711 +SyncHandler.init();
1.712 +PageStyleListener.init();
1.713 +SessionHistoryListener.init();
1.714 +SessionStorageListener.init();
1.715 +ScrollPositionListener.init();
1.716 +DocShellCapabilitiesListener.init();
1.717 +PrivacyListener.init();
1.718 +
1.719 +addEventListener("unload", () => {
1.720 + // Remove all registered nsIObservers.
1.721 + PageStyleListener.uninit();
1.722 + SessionStorageListener.uninit();
1.723 + SessionHistoryListener.uninit();
1.724 +
1.725 + // We don't need to take care of any gFrameTree observers as the gFrameTree
1.726 + // will die with the content script. The same goes for the privacy transition
1.727 + // observer that will die with the docShell when the tab is closed.
1.728 +});
