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Diffstat (limited to 'application/basilisk/components/sessionstore/SessionFile.jsm')
| -rw-r--r-- | application/basilisk/components/sessionstore/SessionFile.jsm | 399 |
1 files changed, 0 insertions, 399 deletions
diff --git a/application/basilisk/components/sessionstore/SessionFile.jsm b/application/basilisk/components/sessionstore/SessionFile.jsm deleted file mode 100644 index 2fdf2e101..000000000 --- a/application/basilisk/components/sessionstore/SessionFile.jsm +++ /dev/null @@ -1,399 +0,0 @@ -/* 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 = ["SessionFile"]; - -/** - * Implementation of all the disk I/O required by the session store. - * This is a private API, meant to be used only by the session store. - * It will change. Do not use it for any other purpose. - * - * Note that this module implicitly depends on one of two things: - * 1. either the asynchronous file I/O system enqueues its requests - * and never attempts to simultaneously execute two I/O requests on - * the files used by this module from two distinct threads; or - * 2. the clients of this API are well-behaved and do not place - * concurrent requests to the files used by this module. - * - * Otherwise, we could encounter bugs, especially under Windows, - * e.g. if a request attempts to write sessionstore.js while - * another attempts to copy that file. - * - * This implementation uses OS.File, which guarantees property 1. - */ - -const Cu = Components.utils; -const Cc = Components.classes; -const Ci = Components.interfaces; -const Cr = Components.results; - -Cu.import("resource://gre/modules/Services.jsm"); -Cu.import("resource://gre/modules/XPCOMUtils.jsm"); -Cu.import("resource://gre/modules/osfile.jsm"); -Cu.import("resource://gre/modules/Promise.jsm"); -Cu.import("resource://gre/modules/AsyncShutdown.jsm"); -Cu.import("resource://gre/modules/Preferences.jsm"); - -XPCOMUtils.defineLazyModuleGetter(this, "console", - "resource://gre/modules/Console.jsm"); -XPCOMUtils.defineLazyModuleGetter(this, "PromiseUtils", - "resource://gre/modules/PromiseUtils.jsm"); -XPCOMUtils.defineLazyModuleGetter(this, "RunState", - "resource:///modules/sessionstore/RunState.jsm"); -XPCOMUtils.defineLazyModuleGetter(this, "TelemetryStopwatch", - "resource://gre/modules/TelemetryStopwatch.jsm"); -XPCOMUtils.defineLazyModuleGetter(this, "Task", - "resource://gre/modules/Task.jsm"); -XPCOMUtils.defineLazyServiceGetter(this, "Telemetry", - "@mozilla.org/base/telemetry;1", "nsITelemetry"); -XPCOMUtils.defineLazyServiceGetter(this, "sessionStartup", - "@mozilla.org/browser/sessionstartup;1", "nsISessionStartup"); -XPCOMUtils.defineLazyModuleGetter(this, "SessionWorker", - "resource:///modules/sessionstore/SessionWorker.jsm"); -XPCOMUtils.defineLazyModuleGetter(this, "SessionStore", - "resource:///modules/sessionstore/SessionStore.jsm"); - -const PREF_UPGRADE_BACKUP = "browser.sessionstore.upgradeBackup.latestBuildID"; -const PREF_MAX_UPGRADE_BACKUPS = "browser.sessionstore.upgradeBackup.maxUpgradeBackups"; - -const PREF_MAX_SERIALIZE_BACK = "browser.sessionstore.max_serialize_back"; -const PREF_MAX_SERIALIZE_FWD = "browser.sessionstore.max_serialize_forward"; - -this.SessionFile = { - /** - * Read the contents of the session file, asynchronously. - */ - read: function () { - return SessionFileInternal.read(); - }, - /** - * Write the contents of the session file, asynchronously. - */ - write: function (aData) { - return SessionFileInternal.write(aData); - }, - /** - * Wipe the contents of the session file, asynchronously. - */ - wipe: function () { - return SessionFileInternal.wipe(); - }, - - /** - * Return the paths to the files used to store, backup, etc. - * the state of the file. - */ - get Paths() { - return SessionFileInternal.Paths; - } -}; - -Object.freeze(SessionFile); - -var Path = OS.Path; -var profileDir = OS.Constants.Path.profileDir; - -var SessionFileInternal = { - Paths: Object.freeze({ - // The path to the latest version of sessionstore written during a clean - // shutdown. After startup, it is renamed `cleanBackup`. - clean: Path.join(profileDir, "sessionstore.js"), - - // The path at which we store the previous version of `clean`. Updated - // whenever we successfully load from `clean`. - cleanBackup: Path.join(profileDir, "sessionstore-backups", "previous.js"), - - // The directory containing all sessionstore backups. - backups: Path.join(profileDir, "sessionstore-backups"), - - // The path to the latest version of the sessionstore written - // during runtime. Generally, this file contains more - // privacy-sensitive information than |clean|, and this file is - // therefore removed during clean shutdown. This file is designed to protect - // against crashes / sudden shutdown. - recovery: Path.join(profileDir, "sessionstore-backups", "recovery.js"), - - // The path to the previous version of the sessionstore written - // during runtime (e.g. 15 seconds before recovery). In case of a - // clean shutdown, this file is removed. Generally, this file - // contains more privacy-sensitive information than |clean|, and - // this file is therefore removed during clean shutdown. This - // file is designed to protect against crashes that are nasty - // enough to corrupt |recovery|. - recoveryBackup: Path.join(profileDir, "sessionstore-backups", "recovery.bak"), - - // The path to a backup created during an upgrade of Firefox. - // Having this backup protects the user essentially from bugs in - // Firefox or add-ons, especially for users of Nightly. This file - // does not contain any information more sensitive than |clean|. - upgradeBackupPrefix: Path.join(profileDir, "sessionstore-backups", "upgrade.js-"), - - // The path to the backup of the version of the session store used - // during the latest upgrade of Firefox. During load/recovery, - // this file should be used if both |path|, |backupPath| and - // |latestStartPath| are absent/incorrect. May be "" if no - // upgrade backup has ever been performed. This file does not - // contain any information more sensitive than |clean|. - get upgradeBackup() { - let latestBackupID = SessionFileInternal.latestUpgradeBackupID; - if (!latestBackupID) { - return ""; - } - return this.upgradeBackupPrefix + latestBackupID; - }, - - // The path to a backup created during an upgrade of Firefox. - // Having this backup protects the user essentially from bugs in - // Firefox, especially for users of Nightly. - get nextUpgradeBackup() { - return this.upgradeBackupPrefix + Services.appinfo.platformBuildID; - }, - - /** - * The order in which to search for a valid sessionstore file. - */ - get loadOrder() { - // If `clean` exists and has been written without corruption during - // the latest shutdown, we need to use it. - // - // Otherwise, `recovery` and `recoveryBackup` represent the most - // recent state of the session store. - // - // Finally, if nothing works, fall back to the last known state - // that can be loaded (`cleanBackup`) or, if available, to the - // backup performed during the latest upgrade. - let order = ["clean", - "recovery", - "recoveryBackup", - "cleanBackup"]; - if (SessionFileInternal.latestUpgradeBackupID) { - // We have an upgradeBackup - order.push("upgradeBackup"); - } - return order; - }, - }), - - // Number of attempted calls to `write`. - // Note that we may have _attempts > _successes + _failures, - // if attempts never complete. - // Used for error reporting. - _attempts: 0, - - // Number of successful calls to `write`. - // Used for error reporting. - _successes: 0, - - // Number of failed calls to `write`. - // Used for error reporting. - _failures: 0, - - // Resolved once initialization is complete. - // The promise never rejects. - _deferredInitialized: PromiseUtils.defer(), - - // `true` once we have started initialization, i.e. once something - // has been scheduled that will eventually resolve `_deferredInitialized`. - _initializationStarted: false, - - // The ID of the latest version of Goanna for which we have an upgrade backup - // or |undefined| if no upgrade backup was ever written. - get latestUpgradeBackupID() { - try { - return Services.prefs.getCharPref(PREF_UPGRADE_BACKUP); - } catch (ex) { - return undefined; - } - }, - - // Find the correct session file, read it and setup the worker. - read: Task.async(function* () { - this._initializationStarted = true; - - let result; - let noFilesFound = true; - // Attempt to load by order of priority from the various backups - for (let key of this.Paths.loadOrder) { - let corrupted = false; - let exists = true; - try { - let path = this.Paths[key]; - let startMs = Date.now(); - - let source = yield OS.File.read(path, { encoding: "utf-8" }); - let parsed = JSON.parse(source); - - if (!SessionStore.isFormatVersionCompatible(parsed.version || ["sessionrestore", 0] /*fallback for old versions*/)) { - // Skip sessionstore files that we don't understand. - Cu.reportError("Cannot extract data from Session Restore file " + path + ". Wrong format/version: " + JSON.stringify(parsed.version) + "."); - continue; - } - result = { - origin: key, - source: source, - parsed: parsed - }; - Telemetry.getHistogramById("FX_SESSION_RESTORE_CORRUPT_FILE"). - add(false); - Telemetry.getHistogramById("FX_SESSION_RESTORE_READ_FILE_MS"). - add(Date.now() - startMs); - break; - } catch (ex if ex instanceof OS.File.Error && ex.becauseNoSuchFile) { - exists = false; - } catch (ex if ex instanceof OS.File.Error) { - // The file might be inaccessible due to wrong permissions - // or similar failures. We'll just count it as "corrupted". - console.error("Could not read session file ", ex, ex.stack); - corrupted = true; - } catch (ex if ex instanceof SyntaxError) { - console.error("Corrupt session file (invalid JSON found) ", ex, ex.stack); - // File is corrupted, try next file - corrupted = true; - } finally { - if (exists) { - noFilesFound = false; - Telemetry.getHistogramById("FX_SESSION_RESTORE_CORRUPT_FILE"). - add(corrupted); - } - } - } - - // All files are corrupted if files found but none could deliver a result. - let allCorrupt = !noFilesFound && !result; - Telemetry.getHistogramById("FX_SESSION_RESTORE_ALL_FILES_CORRUPT"). - add(allCorrupt); - - if (!result) { - // If everything fails, start with an empty session. - result = { - origin: "empty", - source: "", - parsed: null - }; - } - - result.noFilesFound = noFilesFound; - - // Initialize the worker (in the background) to let it handle backups and also - // as a workaround for bug 964531. - let promiseInitialized = SessionWorker.post("init", [result.origin, this.Paths, { - maxUpgradeBackups: Preferences.get(PREF_MAX_UPGRADE_BACKUPS, 3), - maxSerializeBack: Preferences.get(PREF_MAX_SERIALIZE_BACK, 10), - maxSerializeForward: Preferences.get(PREF_MAX_SERIALIZE_FWD, -1) - }]); - - promiseInitialized.catch(err => { - // Ensure that we report errors but that they do not stop us. - Promise.reject(err); - }).then(() => this._deferredInitialized.resolve()); - - return result; - }), - - // Post a message to the worker, making sure that it has been initialized - // first. - _postToWorker: Task.async(function*(...args) { - if (!this._initializationStarted) { - // Initializing the worker is somewhat complex, as proper handling of - // backups requires us to first read and check the session. Consequently, - // the only way to initialize the worker is to first call `this.read()`. - - // The call to `this.read()` causes background initialization of the worker. - // Initialization will be complete once `this._deferredInitialized.promise` - // resolves. - this.read(); - } - yield this._deferredInitialized.promise; - return SessionWorker.post(...args) - }), - - write: function (aData) { - if (RunState.isClosed) { - return Promise.reject(new Error("SessionFile is closed")); - } - - let isFinalWrite = false; - if (RunState.isClosing) { - // If shutdown has started, we will want to stop receiving - // write instructions. - isFinalWrite = true; - RunState.setClosed(); - } - - let performShutdownCleanup = isFinalWrite && - !sessionStartup.isAutomaticRestoreEnabled(); - - this._attempts++; - let options = {isFinalWrite, performShutdownCleanup}; - let promise = this._postToWorker("write", [aData, options]); - - // Wait until the write is done. - promise = promise.then(msg => { - // Record how long the write took. - this._recordTelemetry(msg.telemetry); - this._successes++; - if (msg.result.upgradeBackup) { - // We have just completed a backup-on-upgrade, store the information - // in preferences. - Services.prefs.setCharPref(PREF_UPGRADE_BACKUP, - Services.appinfo.platformBuildID); - } - }, err => { - // Catch and report any errors. - console.error("Could not write session state file ", err, err.stack); - this._failures++; - // By not doing anything special here we ensure that |promise| cannot - // be rejected anymore. The shutdown/cleanup code at the end of the - // function will thus always be executed. - }); - - // Ensure that we can write sessionstore.js cleanly before the profile - // becomes unaccessible. - AsyncShutdown.profileBeforeChange.addBlocker( - "SessionFile: Finish writing Session Restore data", - promise, - { - fetchState: () => ({ - options, - attempts: this._attempts, - successes: this._successes, - failures: this._failures, - }) - }); - - // This code will always be executed because |promise| can't fail anymore. - // We ensured that by having a reject handler that reports the failure but - // doesn't forward the rejection. - return promise.then(() => { - // Remove the blocker, no matter if writing failed or not. - AsyncShutdown.profileBeforeChange.removeBlocker(promise); - - if (isFinalWrite) { - Services.obs.notifyObservers(null, "sessionstore-final-state-write-complete", ""); - } - }); - }, - - wipe: function () { - return this._postToWorker("wipe"); - }, - - _recordTelemetry: function(telemetry) { - for (let id of Object.keys(telemetry)){ - let value = telemetry[id]; - let samples = []; - if (Array.isArray(value)) { - samples.push(...value); - } else { - samples.push(value); - } - let histogram = Telemetry.getHistogramById(id); - for (let sample of samples) { - histogram.add(sample); - } - } - } -}; |