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Diffstat (limited to 'application/basilisk/components/sessionstore/SessionWorker.js')
| -rw-r--r-- | application/basilisk/components/sessionstore/SessionWorker.js | 381 |
1 files changed, 0 insertions, 381 deletions
diff --git a/application/basilisk/components/sessionstore/SessionWorker.js b/application/basilisk/components/sessionstore/SessionWorker.js deleted file mode 100644 index 7d802a7df..000000000 --- a/application/basilisk/components/sessionstore/SessionWorker.js +++ /dev/null @@ -1,381 +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/. */ - -/** - * A worker dedicated to handle I/O for Session Store. - */ - -"use strict"; - -importScripts("resource://gre/modules/osfile.jsm"); - -var PromiseWorker = require("resource://gre/modules/workers/PromiseWorker.js"); - -var File = OS.File; -var Encoder = new TextEncoder(); -var Decoder = new TextDecoder(); - -var worker = new PromiseWorker.AbstractWorker(); -worker.dispatch = function(method, args = []) { - return Agent[method](...args); -}; -worker.postMessage = function(result, ...transfers) { - self.postMessage(result, ...transfers); -}; -worker.close = function() { - self.close(); -}; - -self.addEventListener("message", msg => worker.handleMessage(msg)); - -// The various possible states - -/** - * We just started (we haven't written anything to disk yet) from - * `Paths.clean`. The backup directory may not exist. - */ -const STATE_CLEAN = "clean"; -/** - * We know that `Paths.recovery` is good, either because we just read - * it (we haven't written anything to disk yet) or because have - * already written once to `Paths.recovery` during this session. - * `Paths.clean` is absent or invalid. The backup directory exists. - */ -const STATE_RECOVERY = "recovery"; -/** - * We just started from `Paths.recoverBackupy` (we haven't written - * anything to disk yet). Both `Paths.clean` and `Paths.recovery` are - * absent or invalid. The backup directory exists. - */ -const STATE_RECOVERY_BACKUP = "recoveryBackup"; -/** - * We just started from `Paths.upgradeBackup` (we haven't written - * anything to disk yet). Both `Paths.clean`, `Paths.recovery` and - * `Paths.recoveryBackup` are absent or invalid. The backup directory - * exists. - */ -const STATE_UPGRADE_BACKUP = "upgradeBackup"; -/** - * We just started without a valid session store file (we haven't - * written anything to disk yet). The backup directory may not exist. - */ -const STATE_EMPTY = "empty"; - -var Agent = { - // Path to the files used by the SessionWorker - Paths: null, - - /** - * The current state of the worker, as one of the following strings: - * - "permanent", once the first write has been completed; - * - "empty", before the first write has been completed, - * if we have started without any sessionstore; - * - one of "clean", "recovery", "recoveryBackup", "cleanBackup", - * "upgradeBackup", before the first write has been completed, if - * we have started by loading the corresponding file. - */ - state: null, - - /** - * Number of old upgrade backups that are being kept - */ - maxUpgradeBackups: null, - - /** - * Initialize (or reinitialize) the worker - * - * @param {string} origin Which of sessionstore.js or its backups - * was used. One of the `STATE_*` constants defined above. - * @param {object} paths The paths at which to find the various files. - * @param {object} prefs The preferences the worker needs to known. - */ - init(origin, paths, prefs = {}) { - if (!(origin in paths || origin == STATE_EMPTY)) { - throw new TypeError("Invalid origin: " + origin); - } - - // Check that all required preference values were passed. - for (let pref of ["maxUpgradeBackups", "maxSerializeBack", "maxSerializeForward"]) { - if (!prefs.hasOwnProperty(pref)) { - throw new TypeError(`Missing preference value for ${pref}`); - } - } - - this.state = origin; - this.Paths = paths; - this.maxUpgradeBackups = prefs.maxUpgradeBackups; - this.maxSerializeBack = prefs.maxSerializeBack; - this.maxSerializeForward = prefs.maxSerializeForward; - this.upgradeBackupNeeded = paths.nextUpgradeBackup != paths.upgradeBackup; - return {result: true}; - }, - - /** - * Write the session to disk. - * Write the session to disk, performing any necessary backup - * along the way. - * - * @param {object} state The state to write to disk. - * @param {object} options - * - performShutdownCleanup If |true|, we should - * perform shutdown-time cleanup to ensure that private data - * is not left lying around; - * - isFinalWrite If |true|, write to Paths.clean instead of - * Paths.recovery - */ - write: function (state, options = {}) { - let exn; - let telemetry = {}; - - // Cap the number of backward and forward shistory entries on shutdown. - if (options.isFinalWrite) { - for (let window of state.windows) { - for (let tab of window.tabs) { - let lower = 0; - let upper = tab.entries.length; - - if (this.maxSerializeBack > -1) { - lower = Math.max(lower, tab.index - this.maxSerializeBack - 1); - } - if (this.maxSerializeForward > -1) { - upper = Math.min(upper, tab.index + this.maxSerializeForward); - } - - tab.entries = tab.entries.slice(lower, upper); - tab.index -= lower; - } - } - } - - let stateString = JSON.stringify(state); - let data = Encoder.encode(stateString); - - try { - - if (this.state == STATE_CLEAN || this.state == STATE_EMPTY) { - // The backups directory may not exist yet. In all other cases, - // we have either already read from or already written to this - // directory, so we are satisfied that it exists. - File.makeDir(this.Paths.backups); - } - - if (this.state == STATE_CLEAN) { - // Move $Path.clean out of the way, to avoid any ambiguity as - // to which file is more recent. - File.move(this.Paths.clean, this.Paths.cleanBackup); - } - - let startWriteMs = Date.now(); - - if (options.isFinalWrite) { - // We are shutting down. At this stage, we know that - // $Paths.clean is either absent or corrupted. If it was - // originally present and valid, it has been moved to - // $Paths.cleanBackup a long time ago. We can therefore write - // with the guarantees that we erase no important data. - File.writeAtomic(this.Paths.clean, data, { - tmpPath: this.Paths.clean + ".tmp" - }); - } else if (this.state == STATE_RECOVERY) { - // At this stage, either $Paths.recovery was written >= 15 - // seconds ago during this session or we have just started - // from $Paths.recovery left from the previous session. Either - // way, $Paths.recovery is good. We can move $Path.backup to - // $Path.recoveryBackup without erasing a good file with a bad - // file. - File.writeAtomic(this.Paths.recovery, data, { - tmpPath: this.Paths.recovery + ".tmp", - backupTo: this.Paths.recoveryBackup - }); - } else { - // In other cases, either $Path.recovery is not necessary, or - // it doesn't exist or it has been corrupted. Regardless, - // don't backup $Path.recovery. - File.writeAtomic(this.Paths.recovery, data, { - tmpPath: this.Paths.recovery + ".tmp" - }); - } - - telemetry.FX_SESSION_RESTORE_WRITE_FILE_MS = Date.now() - startWriteMs; - telemetry.FX_SESSION_RESTORE_FILE_SIZE_BYTES = data.byteLength; - - } catch (ex) { - // Don't throw immediately - exn = exn || ex; - } - - // If necessary, perform an upgrade backup - let upgradeBackupComplete = false; - if (this.upgradeBackupNeeded - && (this.state == STATE_CLEAN || this.state == STATE_UPGRADE_BACKUP)) { - try { - // If we loaded from `clean`, the file has since then been renamed to `cleanBackup`. - let path = this.state == STATE_CLEAN ? this.Paths.cleanBackup : this.Paths.upgradeBackup; - File.copy(path, this.Paths.nextUpgradeBackup); - this.upgradeBackupNeeded = false; - upgradeBackupComplete = true; - } catch (ex) { - // Don't throw immediately - exn = exn || ex; - } - - // Find all backups - let iterator; - let backups = []; // array that will contain the paths to all upgrade backup - let upgradeBackupPrefix = this.Paths.upgradeBackupPrefix; // access for forEach callback - - try { - iterator = new File.DirectoryIterator(this.Paths.backups); - iterator.forEach(function (file) { - if (file.path.startsWith(upgradeBackupPrefix)) { - backups.push(file.path); - } - }, this); - } catch (ex) { - // Don't throw immediately - exn = exn || ex; - } finally { - if (iterator) { - iterator.close(); - } - } - - // If too many backups exist, delete them - if (backups.length > this.maxUpgradeBackups) { - // Use alphanumerical sort since dates are in YYYYMMDDHHMMSS format - backups.sort().forEach((file, i) => { - // remove backup file if it is among the first (n-maxUpgradeBackups) files - if (i < backups.length - this.maxUpgradeBackups) { - File.remove(file); - } - }); - } - } - - if (options.performShutdownCleanup && !exn) { - - // During shutdown, if auto-restore is disabled, we need to - // remove possibly sensitive data that has been stored purely - // for crash recovery. Note that this slightly decreases our - // ability to recover from OS-level/hardware-level issue. - - // If an exception was raised, we assume that we still need - // these files. - File.remove(this.Paths.recoveryBackup); - File.remove(this.Paths.recovery); - } - - this.state = STATE_RECOVERY; - - if (exn) { - throw exn; - } - - return { - result: { - upgradeBackup: upgradeBackupComplete - }, - telemetry: telemetry, - }; - }, - - /** - * Wipes all files holding session data from disk. - */ - wipe: function () { - - // Don't stop immediately in case of error. - let exn = null; - - // Erase main session state file - try { - File.remove(this.Paths.clean); - } catch (ex) { - // Don't stop immediately. - exn = exn || ex; - } - - // Wipe the Session Restore directory - try { - this._wipeFromDir(this.Paths.backups, null); - } catch (ex) { - exn = exn || ex; - } - - try { - File.removeDir(this.Paths.backups); - } catch (ex) { - exn = exn || ex; - } - - // Wipe legacy Ression Restore files from the profile directory - try { - this._wipeFromDir(OS.Constants.Path.profileDir, "sessionstore.bak"); - } catch (ex) { - exn = exn || ex; - } - - - this.state = STATE_EMPTY; - if (exn) { - throw exn; - } - - return { result: true }; - }, - - /** - * Wipe a number of files from a directory. - * - * @param {string} path The directory. - * @param {string|null} prefix If provided, only remove files whose - * name starts with a specific prefix. - */ - _wipeFromDir: function(path, prefix) { - // Sanity check - if (typeof prefix == "undefined" || prefix == "") { - throw new TypeError(); - } - - let exn = null; - - let iterator = new File.DirectoryIterator(path); - try { - if (!iterator.exists()) { - return; - } - for (let entry in iterator) { - if (entry.isDir) { - continue; - } - if (!prefix || entry.name.startsWith(prefix)) { - try { - File.remove(entry.path); - } catch (ex) { - // Don't stop immediately - exn = exn || ex; - } - } - } - - if (exn) { - throw exn; - } - } finally { - iterator.close(); - } - }, -}; - -function isNoSuchFileEx(aReason) { - return aReason instanceof OS.File.Error && aReason.becauseNoSuchFile; -} - -/** - * Estimate the number of bytes that a data structure will use on disk - * once serialized. - */ -function getByteLength(str) { - return Encoder.encode(JSON.stringify(str)).byteLength; -} |