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authorMatt A. Tobin <mattatobin@localhost.localdomain>2018-02-02 04:16:08 -0500
committerMatt A. Tobin <mattatobin@localhost.localdomain>2018-02-02 04:16:08 -0500
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+/* -*- indent-tabs-mode: nil; js-indent-level: 2 -*-
+ * vim: sw=2 ts=2 sts=2 expandtab
+ * 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/. */
+
+/**
+ * This component handles history and orphans expiration through asynchronous
+ * Storage statements.
+ * Expiration runs:
+ * - At idle, but just once, we stop any other kind of expiration during idle
+ * to preserve batteries in portable devices.
+ * - At shutdown, only if the database is dirty, we should still avoid to
+ * expire too heavily on shutdown.
+ * - On ClearHistory we run a full expiration for privacy reasons.
+ * - On a repeating timer we expire in small chunks.
+ *
+ * Expiration algorithm will adapt itself based on:
+ * - Memory size of the device.
+ * - Status of the database (clean or dirty).
+ */
+
+const Cc = Components.classes;
+const Ci = Components.interfaces;
+const Cu = Components.utils;
+
+Cu.import("resource://gre/modules/XPCOMUtils.jsm");
+Cu.import("resource://gre/modules/Services.jsm");
+Cu.import("resource://gre/modules/Task.jsm");
+
+XPCOMUtils.defineLazyModuleGetter(this, "PlacesUtils",
+ "resource://gre/modules/PlacesUtils.jsm");
+
+// Constants
+
+// Last expiration step should run before the final sync.
+const TOPIC_SHUTDOWN = "places-will-close-connection";
+const TOPIC_PREF_CHANGED = "nsPref:changed";
+const TOPIC_DEBUG_START_EXPIRATION = "places-debug-start-expiration";
+const TOPIC_EXPIRATION_FINISHED = "places-expiration-finished";
+const TOPIC_IDLE_BEGIN = "idle";
+const TOPIC_IDLE_END = "active";
+const TOPIC_IDLE_DAILY = "idle-daily";
+const TOPIC_TESTING_MODE = "testing-mode";
+const TOPIC_TEST_INTERVAL_CHANGED = "test-interval-changed";
+
+// Branch for all expiration preferences.
+const PREF_BRANCH = "places.history.expiration.";
+
+// Max number of unique URIs to retain in history.
+// Notice this is a lazy limit. This means we will start to expire if we will
+// go over it, but we won't ensure that we will stop exactly when we reach it,
+// instead we will stop after the next expiration step that will bring us
+// below it.
+// If this preference does not exist or has a negative value, we will calculate
+// a limit based on current hardware.
+const PREF_MAX_URIS = "max_pages";
+const PREF_MAX_URIS_NOTSET = -1; // Use our internally calculated limit.
+
+// We save the current unique URIs limit to this pref, to make it available to
+// other components without having to duplicate the full logic.
+const PREF_READONLY_CALCULATED_MAX_URIS = "transient_current_max_pages";
+
+// Seconds between each expiration step.
+const PREF_INTERVAL_SECONDS = "interval_seconds";
+const PREF_INTERVAL_SECONDS_NOTSET = 3 * 60;
+
+// We calculate an optimal database size, based on hardware specs.
+// This percentage of memory size is used to protect against calculating a too
+// large database size on systems with small memory.
+const DATABASE_TO_MEMORY_PERC = 4;
+// This percentage of disk size is used to protect against calculating a too
+// large database size on disks with tiny quota or available space.
+const DATABASE_TO_DISK_PERC = 2;
+// Maximum size of the optimal database. High-end hardware has plenty of
+// memory and disk space, but performances don't grow linearly.
+const DATABASE_MAX_SIZE = 73400320; // 70MiB
+// If the physical memory size is bogus, fallback to this.
+const MEMSIZE_FALLBACK_BYTES = 268435456; // 256 MiB
+// If the disk available space is bogus, fallback to this.
+const DISKSIZE_FALLBACK_BYTES = 268435456; // 256 MiB
+
+// Max number of entries to expire at each expiration step.
+// This value is globally used for different kind of data we expire, can be
+// tweaked based on data type. See below in getBoundStatement.
+const EXPIRE_LIMIT_PER_STEP = 6;
+// When we run a large expiration step, the above limit is multiplied by this.
+const EXPIRE_LIMIT_PER_LARGE_STEP_MULTIPLIER = 10;
+
+// When history is clean or dirty enough we will adapt the expiration algorithm
+// to be more lazy or more aggressive.
+// This is done acting on the interval between expiration steps and the number
+// of expirable items.
+// 1. Clean history:
+// We expire at (default interval * EXPIRE_AGGRESSIVITY_MULTIPLIER) the
+// default number of entries.
+// 2. Dirty history:
+// We expire at the default interval, but a greater number of entries
+// (default number of entries * EXPIRE_AGGRESSIVITY_MULTIPLIER).
+const EXPIRE_AGGRESSIVITY_MULTIPLIER = 3;
+
+// This is the average size in bytes of an URI entry in the database.
+// Magic numbers are determined through analysis of the distribution of a ratio
+// between number of unique URIs and database size among our users.
+// Used as a fall back value when it's not possible to calculate the real value.
+const URIENTRY_AVG_SIZE = 600;
+
+// Seconds of idle time before starting a larger expiration step.
+// Notice during idle we stop the expiration timer since we don't want to hurt
+// stand-by or mobile devices batteries.
+const IDLE_TIMEOUT_SECONDS = 5 * 60;
+
+// If a clear history ran just before we shutdown, we will skip most of the
+// expiration at shutdown. This is maximum number of seconds from last
+// clearHistory to decide to skip expiration at shutdown.
+const SHUTDOWN_WITH_RECENT_CLEARHISTORY_TIMEOUT_SECONDS = 10;
+
+// If the pages delta from the last ANALYZE is over this threashold, the tables
+// should be analyzed again.
+const ANALYZE_PAGES_THRESHOLD = 100;
+
+// If the number of pages over history limit is greater than this threshold,
+// expiration will be more aggressive, to bring back history to a saner size.
+const OVERLIMIT_PAGES_THRESHOLD = 1000;
+
+const MSECS_PER_DAY = 86400000;
+const ANNOS_EXPIRE_POLICIES = [
+ { bind: "expire_days",
+ type: Ci.nsIAnnotationService.EXPIRE_DAYS,
+ time: 7 * 1000 * MSECS_PER_DAY },
+ { bind: "expire_weeks",
+ type: Ci.nsIAnnotationService.EXPIRE_WEEKS,
+ time: 30 * 1000 * MSECS_PER_DAY },
+ { bind: "expire_months",
+ type: Ci.nsIAnnotationService.EXPIRE_MONTHS,
+ time: 180 * 1000 * MSECS_PER_DAY },
+];
+
+// When we expire we can use these limits:
+// - SMALL for usual partial expirations, will expire a small chunk.
+// - LARGE for idle or shutdown expirations, will expire a large chunk.
+// - UNLIMITED for clearHistory, will expire everything.
+// - DEBUG will use a known limit, passed along with the debug notification.
+const LIMIT = {
+ SMALL: 0,
+ LARGE: 1,
+ UNLIMITED: 2,
+ DEBUG: 3,
+};
+
+// Represents the status of history database.
+const STATUS = {
+ CLEAN: 0,
+ DIRTY: 1,
+ UNKNOWN: 2,
+};
+
+// Represents actions on which a query will run.
+const ACTION = {
+ TIMED: 1 << 0, // happens every this._interval
+ TIMED_OVERLIMIT: 1 << 1, // like TIMED but only when history is over limits
+ TIMED_ANALYZE: 1 << 2, // happens when ANALYZE statistics should be updated
+ CLEAR_HISTORY: 1 << 3, // happens when history is cleared
+ SHUTDOWN_DIRTY: 1 << 4, // happens at shutdown for DIRTY state
+ IDLE_DIRTY: 1 << 5, // happens on idle for DIRTY state
+ IDLE_DAILY: 1 << 6, // happens once a day on idle
+ DEBUG: 1 << 7, // happens on TOPIC_DEBUG_START_EXPIRATION
+};
+
+// The queries we use to expire.
+const EXPIRATION_QUERIES = {
+
+ // Some visits can be expired more often than others, cause they are less
+ // useful to the user and can pollute awesomebar results:
+ // 1. urls over 255 chars
+ // 2. redirect sources and downloads
+ // Note: due to the REPLACE option, this should be executed before
+ // QUERY_FIND_VISITS_TO_EXPIRE, that has a more complete result.
+ QUERY_FIND_EXOTIC_VISITS_TO_EXPIRE: {
+ sql: `INSERT INTO expiration_notify (v_id, url, guid, visit_date, reason)
+ SELECT v.id, h.url, h.guid, v.visit_date, "exotic"
+ FROM moz_historyvisits v
+ JOIN moz_places h ON h.id = v.place_id
+ WHERE visit_date < strftime('%s','now','localtime','start of day','-60 days','utc') * 1000000
+ AND ( LENGTH(h.url) > 255 OR v.visit_type = 7 )
+ ORDER BY v.visit_date ASC
+ LIMIT :limit_visits`,
+ actions: ACTION.TIMED_OVERLIMIT | ACTION.IDLE_DIRTY | ACTION.IDLE_DAILY |
+ ACTION.DEBUG
+ },
+
+ // Finds visits to be expired when history is over the unique pages limit,
+ // otherwise will return nothing.
+ // This explicitly excludes any visits added in the last 7 days, to protect
+ // users with thousands of bookmarks from constantly losing history.
+ QUERY_FIND_VISITS_TO_EXPIRE: {
+ sql: `INSERT INTO expiration_notify
+ (v_id, url, guid, visit_date, expected_results)
+ SELECT v.id, h.url, h.guid, v.visit_date, :limit_visits
+ FROM moz_historyvisits v
+ JOIN moz_places h ON h.id = v.place_id
+ WHERE (SELECT COUNT(*) FROM moz_places) > :max_uris
+ AND visit_date < strftime('%s','now','localtime','start of day','-7 days','utc') * 1000000
+ ORDER BY v.visit_date ASC
+ LIMIT :limit_visits`,
+ actions: ACTION.TIMED_OVERLIMIT | ACTION.IDLE_DIRTY | ACTION.IDLE_DAILY |
+ ACTION.DEBUG
+ },
+
+ // Removes the previously found visits.
+ QUERY_EXPIRE_VISITS: {
+ sql: `DELETE FROM moz_historyvisits WHERE id IN (
+ SELECT v_id FROM expiration_notify WHERE v_id NOTNULL
+ )`,
+ actions: ACTION.TIMED_OVERLIMIT | ACTION.IDLE_DIRTY | ACTION.IDLE_DAILY |
+ ACTION.DEBUG
+ },
+
+ // Finds orphan URIs in the database.
+ // Notice we won't notify single removed URIs on History.clear(), so we don't
+ // run this query in such a case, but just delete URIs.
+ // This could run in the middle of adding a visit or bookmark to a new page.
+ // In such a case since it is async, could end up expiring the orphan page
+ // before it actually gets the new visit or bookmark.
+ // Thus, since new pages get frecency -1, we filter on that.
+ QUERY_FIND_URIS_TO_EXPIRE: {
+ sql: `INSERT INTO expiration_notify (p_id, url, guid, visit_date)
+ SELECT h.id, h.url, h.guid, h.last_visit_date
+ FROM moz_places h
+ LEFT JOIN moz_historyvisits v ON h.id = v.place_id
+ WHERE h.last_visit_date IS NULL
+ AND h.foreign_count = 0
+ AND v.id IS NULL
+ AND frecency <> -1
+ LIMIT :limit_uris`,
+ actions: ACTION.TIMED | ACTION.TIMED_OVERLIMIT | ACTION.SHUTDOWN_DIRTY |
+ ACTION.IDLE_DIRTY | ACTION.IDLE_DAILY | ACTION.DEBUG
+ },
+
+ // Expire found URIs from the database.
+ QUERY_EXPIRE_URIS: {
+ sql: `DELETE FROM moz_places WHERE id IN (
+ SELECT p_id FROM expiration_notify WHERE p_id NOTNULL
+ ) AND foreign_count = 0 AND last_visit_date ISNULL`,
+ actions: ACTION.TIMED | ACTION.TIMED_OVERLIMIT | ACTION.SHUTDOWN_DIRTY |
+ ACTION.IDLE_DIRTY | ACTION.IDLE_DAILY | ACTION.DEBUG
+ },
+
+ // Expire orphan URIs from the database.
+ QUERY_SILENT_EXPIRE_ORPHAN_URIS: {
+ sql: `DELETE FROM moz_places WHERE id IN (
+ SELECT h.id
+ FROM moz_places h
+ LEFT JOIN moz_historyvisits v ON h.id = v.place_id
+ WHERE h.last_visit_date IS NULL
+ AND h.foreign_count = 0
+ AND v.id IS NULL
+ LIMIT :limit_uris
+ )`,
+ actions: ACTION.CLEAR_HISTORY
+ },
+
+ // Hosts accumulated during the places delete are updated through a trigger
+ // (see nsPlacesTriggers.h).
+ QUERY_UPDATE_HOSTS: {
+ sql: `DELETE FROM moz_updatehosts_temp`,
+ actions: ACTION.CLEAR_HISTORY | ACTION.TIMED | ACTION.TIMED_OVERLIMIT |
+ ACTION.SHUTDOWN_DIRTY | ACTION.IDLE_DIRTY | ACTION.IDLE_DAILY |
+ ACTION.DEBUG
+ },
+
+ // Expire orphan icons from the database.
+ QUERY_EXPIRE_FAVICONS: {
+ sql: `DELETE FROM moz_favicons WHERE id IN (
+ SELECT f.id FROM moz_favicons f
+ LEFT JOIN moz_places h ON f.id = h.favicon_id
+ WHERE h.favicon_id IS NULL
+ LIMIT :limit_favicons
+ )`,
+ actions: ACTION.TIMED | ACTION.TIMED_OVERLIMIT | ACTION.CLEAR_HISTORY |
+ ACTION.SHUTDOWN_DIRTY | ACTION.IDLE_DIRTY | ACTION.IDLE_DAILY |
+ ACTION.DEBUG
+ },
+
+ // Expire orphan page annotations from the database.
+ QUERY_EXPIRE_ANNOS: {
+ sql: `DELETE FROM moz_annos WHERE id in (
+ SELECT a.id FROM moz_annos a
+ LEFT JOIN moz_places h ON a.place_id = h.id
+ WHERE h.id IS NULL
+ LIMIT :limit_annos
+ )`,
+ actions: ACTION.TIMED | ACTION.TIMED_OVERLIMIT | ACTION.CLEAR_HISTORY |
+ ACTION.SHUTDOWN_DIRTY | ACTION.IDLE_DIRTY | ACTION.IDLE_DAILY |
+ ACTION.DEBUG
+ },
+
+ // Expire page annotations based on expiration policy.
+ QUERY_EXPIRE_ANNOS_WITH_POLICY: {
+ sql: `DELETE FROM moz_annos
+ WHERE (expiration = :expire_days
+ AND :expire_days_time > MAX(lastModified, dateAdded))
+ OR (expiration = :expire_weeks
+ AND :expire_weeks_time > MAX(lastModified, dateAdded))
+ OR (expiration = :expire_months
+ AND :expire_months_time > MAX(lastModified, dateAdded))`,
+ actions: ACTION.TIMED | ACTION.TIMED_OVERLIMIT | ACTION.CLEAR_HISTORY |
+ ACTION.SHUTDOWN_DIRTY | ACTION.IDLE_DIRTY | ACTION.IDLE_DAILY |
+ ACTION.DEBUG
+ },
+
+ // Expire items annotations based on expiration policy.
+ QUERY_EXPIRE_ITEMS_ANNOS_WITH_POLICY: {
+ sql: `DELETE FROM moz_items_annos
+ WHERE (expiration = :expire_days
+ AND :expire_days_time > MAX(lastModified, dateAdded))
+ OR (expiration = :expire_weeks
+ AND :expire_weeks_time > MAX(lastModified, dateAdded))
+ OR (expiration = :expire_months
+ AND :expire_months_time > MAX(lastModified, dateAdded))`,
+ actions: ACTION.TIMED | ACTION.TIMED_OVERLIMIT | ACTION.CLEAR_HISTORY |
+ ACTION.SHUTDOWN_DIRTY | ACTION.IDLE_DIRTY | ACTION.IDLE_DAILY |
+ ACTION.DEBUG
+ },
+
+ // Expire page annotations based on expiration policy.
+ QUERY_EXPIRE_ANNOS_WITH_HISTORY: {
+ sql: `DELETE FROM moz_annos
+ WHERE expiration = :expire_with_history
+ AND NOT EXISTS (SELECT id FROM moz_historyvisits
+ WHERE place_id = moz_annos.place_id LIMIT 1)`,
+ actions: ACTION.TIMED | ACTION.TIMED_OVERLIMIT | ACTION.CLEAR_HISTORY |
+ ACTION.SHUTDOWN_DIRTY | ACTION.IDLE_DIRTY | ACTION.IDLE_DAILY |
+ ACTION.DEBUG
+ },
+
+ // Expire item annos without a corresponding item id.
+ QUERY_EXPIRE_ITEMS_ANNOS: {
+ sql: `DELETE FROM moz_items_annos WHERE id IN (
+ SELECT a.id FROM moz_items_annos a
+ LEFT JOIN moz_bookmarks b ON a.item_id = b.id
+ WHERE b.id IS NULL
+ LIMIT :limit_annos
+ )`,
+ actions: ACTION.CLEAR_HISTORY | ACTION.IDLE_DAILY | ACTION.DEBUG
+ },
+
+ // Expire all annotation names without a corresponding annotation.
+ QUERY_EXPIRE_ANNO_ATTRIBUTES: {
+ sql: `DELETE FROM moz_anno_attributes WHERE id IN (
+ SELECT n.id FROM moz_anno_attributes n
+ LEFT JOIN moz_annos a ON n.id = a.anno_attribute_id
+ LEFT JOIN moz_items_annos t ON n.id = t.anno_attribute_id
+ WHERE a.anno_attribute_id IS NULL
+ AND t.anno_attribute_id IS NULL
+ LIMIT :limit_annos
+ )`,
+ actions: ACTION.CLEAR_HISTORY | ACTION.SHUTDOWN_DIRTY | ACTION.IDLE_DIRTY |
+ ACTION.IDLE_DAILY | ACTION.DEBUG
+ },
+
+ // Expire orphan inputhistory.
+ QUERY_EXPIRE_INPUTHISTORY: {
+ sql: `DELETE FROM moz_inputhistory WHERE place_id IN (
+ SELECT i.place_id FROM moz_inputhistory i
+ LEFT JOIN moz_places h ON h.id = i.place_id
+ WHERE h.id IS NULL
+ LIMIT :limit_inputhistory
+ )`,
+ actions: ACTION.TIMED | ACTION.TIMED_OVERLIMIT | ACTION.CLEAR_HISTORY |
+ ACTION.SHUTDOWN_DIRTY | ACTION.IDLE_DIRTY | ACTION.IDLE_DAILY |
+ ACTION.DEBUG
+ },
+
+ // Expire all session annotations. Should only be called at shutdown.
+ QUERY_EXPIRE_ANNOS_SESSION: {
+ sql: "DELETE FROM moz_annos WHERE expiration = :expire_session",
+ actions: ACTION.CLEAR_HISTORY | ACTION.DEBUG
+ },
+
+ // Expire all session item annotations. Should only be called at shutdown.
+ QUERY_EXPIRE_ITEMS_ANNOS_SESSION: {
+ sql: "DELETE FROM moz_items_annos WHERE expiration = :expire_session",
+ actions: ACTION.CLEAR_HISTORY | ACTION.DEBUG
+ },
+
+ // Select entries for notifications.
+ // If p_id is set whole_entry = 1, then we have expired the full page.
+ // Either p_id or v_id are always set.
+ QUERY_SELECT_NOTIFICATIONS: {
+ sql: `SELECT url, guid, MAX(visit_date) AS visit_date,
+ MAX(IFNULL(MIN(p_id, 1), MIN(v_id, 0))) AS whole_entry,
+ MAX(expected_results) AS expected_results,
+ (SELECT MAX(visit_date) FROM expiration_notify
+ WHERE reason = "expired" AND url = n.url AND p_id ISNULL
+ ) AS most_recent_expired_visit
+ FROM expiration_notify n
+ GROUP BY url`,
+ actions: ACTION.TIMED | ACTION.TIMED_OVERLIMIT | ACTION.SHUTDOWN_DIRTY |
+ ACTION.IDLE_DIRTY | ACTION.IDLE_DAILY | ACTION.DEBUG
+ },
+
+ // Empty the notifications table.
+ QUERY_DELETE_NOTIFICATIONS: {
+ sql: "DELETE FROM expiration_notify",
+ actions: ACTION.TIMED | ACTION.TIMED_OVERLIMIT | ACTION.SHUTDOWN_DIRTY |
+ ACTION.IDLE_DIRTY | ACTION.IDLE_DAILY | ACTION.DEBUG
+ },
+
+ // The following queries are used to adjust the sqlite_stat1 table to help the
+ // query planner create better queries. These should always be run LAST, and
+ // are therefore at the end of the object.
+ // Since also nsNavHistory.cpp executes ANALYZE, the analyzed tables
+ // must be the same in both components. So ensure they are in sync.
+
+ QUERY_ANALYZE_MOZ_PLACES: {
+ sql: "ANALYZE moz_places",
+ actions: ACTION.TIMED_OVERLIMIT | ACTION.TIMED_ANALYZE |
+ ACTION.CLEAR_HISTORY | ACTION.IDLE_DAILY | ACTION.DEBUG
+ },
+ QUERY_ANALYZE_MOZ_BOOKMARKS: {
+ sql: "ANALYZE moz_bookmarks",
+ actions: ACTION.TIMED_ANALYZE | ACTION.IDLE_DAILY | ACTION.DEBUG
+ },
+ QUERY_ANALYZE_MOZ_HISTORYVISITS: {
+ sql: "ANALYZE moz_historyvisits",
+ actions: ACTION.TIMED_OVERLIMIT | ACTION.TIMED_ANALYZE |
+ ACTION.CLEAR_HISTORY | ACTION.IDLE_DAILY | ACTION.DEBUG
+ },
+ QUERY_ANALYZE_MOZ_INPUTHISTORY: {
+ sql: "ANALYZE moz_inputhistory",
+ actions: ACTION.TIMED | ACTION.TIMED_OVERLIMIT | ACTION.TIMED_ANALYZE |
+ ACTION.CLEAR_HISTORY | ACTION.IDLE_DAILY | ACTION.DEBUG
+ },
+};
+
+/**
+ * Sends a bookmarks notification through the given observers.
+ *
+ * @param observers
+ * array of nsINavBookmarkObserver objects.
+ * @param notification
+ * the notification name.
+ * @param args
+ * array of arguments to pass to the notification.
+ */
+function notify(observers, notification, args = []) {
+ for (let observer of observers) {
+ try {
+ observer[notification](...args);
+ } catch (ex) {}
+ }
+}
+
+// nsPlacesExpiration definition
+
+function nsPlacesExpiration()
+{
+ // Smart Getters
+
+ XPCOMUtils.defineLazyGetter(this, "_db", function () {
+ let db = Cc["@mozilla.org/browser/nav-history-service;1"].
+ getService(Ci.nsPIPlacesDatabase).
+ DBConnection;
+
+ // Create the temporary notifications table.
+ let stmt = db.createAsyncStatement(
+ `CREATE TEMP TABLE expiration_notify (
+ id INTEGER PRIMARY KEY
+ , v_id INTEGER
+ , p_id INTEGER
+ , url TEXT NOT NULL
+ , guid TEXT NOT NULL
+ , visit_date INTEGER
+ , expected_results INTEGER NOT NULL DEFAULT 0
+ , reason TEXT NOT NULL DEFAULT "expired"
+ )`);
+ stmt.executeAsync();
+ stmt.finalize();
+
+ return db;
+ });
+
+ XPCOMUtils.defineLazyServiceGetter(this, "_idle",
+ "@mozilla.org/widget/idleservice;1",
+ "nsIIdleService");
+
+ this._prefBranch = Cc["@mozilla.org/preferences-service;1"].
+ getService(Ci.nsIPrefService).
+ getBranch(PREF_BRANCH);
+
+ this._loadPrefs().then(() => {
+ // Observe our preferences branch for changes.
+ this._prefBranch.addObserver("", this, true);
+
+ // Create our expiration timer.
+ this._newTimer();
+ }, Cu.reportError);
+
+ // Register topic observers.
+ Services.obs.addObserver(this, TOPIC_SHUTDOWN, true);
+ Services.obs.addObserver(this, TOPIC_DEBUG_START_EXPIRATION, true);
+ Services.obs.addObserver(this, TOPIC_IDLE_DAILY, true);
+}
+
+nsPlacesExpiration.prototype = {
+
+ // nsIObserver
+
+ observe: function PEX_observe(aSubject, aTopic, aData)
+ {
+ if (this._shuttingDown) {
+ return;
+ }
+
+ if (aTopic == TOPIC_SHUTDOWN) {
+ this._shuttingDown = true;
+ this.expireOnIdle = false;
+
+ if (this._timer) {
+ this._timer.cancel();
+ this._timer = null;
+ }
+
+ // If we didn't ran a clearHistory recently and database is dirty, we
+ // want to expire some entries, to speed up the expiration process.
+ let hasRecentClearHistory =
+ Date.now() - this._lastClearHistoryTime <
+ SHUTDOWN_WITH_RECENT_CLEARHISTORY_TIMEOUT_SECONDS * 1000;
+ if (!hasRecentClearHistory && this.status == STATUS.DIRTY) {
+ this._expireWithActionAndLimit(ACTION.SHUTDOWN_DIRTY, LIMIT.LARGE);
+ }
+
+ this._finalizeInternalStatements();
+ }
+ else if (aTopic == TOPIC_PREF_CHANGED) {
+ this._loadPrefs().then(() => {
+ if (aData == PREF_INTERVAL_SECONDS) {
+ // Renew the timer with the new interval value.
+ this._newTimer();
+ }
+ }, Cu.reportError);
+ }
+ else if (aTopic == TOPIC_DEBUG_START_EXPIRATION) {
+ // The passed-in limit is the maximum number of visits to expire when
+ // history is over capacity. Mind to correctly handle the NaN value.
+ let limit = parseInt(aData);
+ if (limit == -1) {
+ // Everything should be expired without any limit. If history is over
+ // capacity then all existing visits will be expired.
+ // Should only be used in tests, since may cause dataloss.
+ this._expireWithActionAndLimit(ACTION.DEBUG, LIMIT.UNLIMITED);
+ }
+ else if (limit > 0) {
+ // The number of expired visits is limited by this amount. It may be
+ // used for testing purposes, like checking that limited queries work.
+ this._debugLimit = limit;
+ this._expireWithActionAndLimit(ACTION.DEBUG, LIMIT.DEBUG);
+ }
+ else {
+ // Any other value is intended as a 0 limit, that means no visits
+ // will be expired. Even if this doesn't touch visits, it will remove
+ // any orphan pages, icons, annotations and similar from the database,
+ // so it may be used for cleanup purposes.
+ this._debugLimit = -1;
+ this._expireWithActionAndLimit(ACTION.DEBUG, LIMIT.DEBUG);
+ }
+ }
+ else if (aTopic == TOPIC_IDLE_BEGIN) {
+ // Stop the expiration timer. We don't want to keep up expiring on idle
+ // to preserve batteries on mobile devices and avoid killing stand-by.
+ if (this._timer) {
+ this._timer.cancel();
+ this._timer = null;
+ }
+ if (this.expireOnIdle)
+ this._expireWithActionAndLimit(ACTION.IDLE_DIRTY, LIMIT.LARGE);
+ }
+ else if (aTopic == TOPIC_IDLE_END) {
+ // Restart the expiration timer.
+ if (!this._timer)
+ this._newTimer();
+ }
+ else if (aTopic == TOPIC_IDLE_DAILY) {
+ this._expireWithActionAndLimit(ACTION.IDLE_DAILY, LIMIT.LARGE);
+ }
+ else if (aTopic == TOPIC_TESTING_MODE) {
+ this._testingMode = true;
+ }
+ },
+
+ // nsINavHistoryObserver
+
+ _inBatchMode: false,
+ onBeginUpdateBatch: function PEX_onBeginUpdateBatch()
+ {
+ this._inBatchMode = true;
+
+ // We do not want to expire while we are doing batch work.
+ if (this._timer) {
+ this._timer.cancel();
+ this._timer = null;
+ }
+ },
+
+ onEndUpdateBatch: function PEX_onEndUpdateBatch()
+ {
+ this._inBatchMode = false;
+
+ // Restore timer.
+ if (!this._timer)
+ this._newTimer();
+ },
+
+ _lastClearHistoryTime: 0,
+ onClearHistory: function PEX_onClearHistory() {
+ this._lastClearHistoryTime = Date.now();
+ // Expire orphans. History status is clean after a clear history.
+ this.status = STATUS.CLEAN;
+ this._expireWithActionAndLimit(ACTION.CLEAR_HISTORY, LIMIT.UNLIMITED);
+ },
+
+ onVisit: function() {},
+ onTitleChanged: function() {},
+ onDeleteURI: function() {},
+ onPageChanged: function() {},
+ onDeleteVisits: function() {},
+
+ // nsITimerCallback
+
+ notify: function PEX_timerCallback()
+ {
+ // Check if we are over history capacity, if so visits must be expired.
+ this._getPagesStats((function onPagesCount(aPagesCount, aStatsCount) {
+ let overLimitPages = aPagesCount - this._urisLimit;
+ this._overLimit = overLimitPages > 0;
+
+ let action = this._overLimit ? ACTION.TIMED_OVERLIMIT : ACTION.TIMED;
+ // If the number of pages changed significantly from the last ANALYZE
+ // update SQLite statistics.
+ if (Math.abs(aPagesCount - aStatsCount) >= ANALYZE_PAGES_THRESHOLD) {
+ action = action | ACTION.TIMED_ANALYZE;
+ }
+
+ // Adapt expiration aggressivity to the number of pages over the limit.
+ let limit = overLimitPages > OVERLIMIT_PAGES_THRESHOLD ? LIMIT.LARGE
+ : LIMIT.SMALL;
+
+ this._expireWithActionAndLimit(action, limit);
+ }).bind(this));
+ },
+
+ // mozIStorageStatementCallback
+
+ handleResult: function PEX_handleResult(aResultSet)
+ {
+ // We don't want to notify after shutdown.
+ if (this._shuttingDown)
+ return;
+
+ let row;
+ while ((row = aResultSet.getNextRow())) {
+ // expected_results is set to the number of expected visits by
+ // QUERY_FIND_VISITS_TO_EXPIRE. We decrease that counter for each found
+ // visit and if it reaches zero we mark the database as dirty, since all
+ // the expected visits were expired, so it's likely the next run will
+ // find more.
+ let expectedResults = row.getResultByName("expected_results");
+ if (expectedResults > 0) {
+ if (!("_expectedResultsCount" in this)) {
+ this._expectedResultsCount = expectedResults;
+ }
+ if (this._expectedResultsCount > 0) {
+ this._expectedResultsCount--;
+ }
+ }
+
+ let uri = Services.io.newURI(row.getResultByName("url"), null, null);
+ let guid = row.getResultByName("guid");
+ let visitDate = row.getResultByName("visit_date");
+ let wholeEntry = row.getResultByName("whole_entry");
+ let mostRecentExpiredVisit = row.getResultByName("most_recent_expired_visit");
+ let reason = Ci.nsINavHistoryObserver.REASON_EXPIRED;
+ let observers = PlacesUtils.history.getObservers();
+
+ if (mostRecentExpiredVisit) {
+ let days = parseInt((Date.now() - (mostRecentExpiredVisit / 1000)) / MSECS_PER_DAY);
+ if (!this._mostRecentExpiredVisitDays) {
+ this._mostRecentExpiredVisitDays = days;
+ }
+ else if (days < this._mostRecentExpiredVisitDays) {
+ this._mostRecentExpiredVisitDays = days;
+ }
+ }
+
+ // Dispatch expiration notifications to history.
+ if (wholeEntry) {
+ notify(observers, "onDeleteURI", [uri, guid, reason]);
+ } else {
+ notify(observers, "onDeleteVisits", [uri, visitDate, guid, reason, 0]);
+ }
+ }
+ },
+
+ handleError: function PEX_handleError(aError)
+ {
+ Cu.reportError("Async statement execution returned with '" +
+ aError.result + "', '" + aError.message + "'");
+ },
+
+ // Number of expiration steps needed to reach a CLEAN status.
+ _telemetrySteps: 1,
+ handleCompletion: function PEX_handleCompletion(aReason)
+ {
+ if (aReason == Ci.mozIStorageStatementCallback.REASON_FINISHED) {
+
+ if (this._mostRecentExpiredVisitDays) {
+ try {
+ Services.telemetry
+ .getHistogramById("PLACES_MOST_RECENT_EXPIRED_VISIT_DAYS")
+ .add(this._mostRecentExpiredVisitDays);
+ } catch (ex) {
+ Components.utils.reportError("Unable to report telemetry.");
+ } finally {
+ delete this._mostRecentExpiredVisitDays;
+ }
+ }
+
+ if ("_expectedResultsCount" in this) {
+ // Adapt the aggressivity of steps based on the status of history.
+ // A dirty history will return all the entries we are expecting bringing
+ // our countdown to zero, while a clean one will not.
+ let oldStatus = this.status;
+ this.status = this._expectedResultsCount == 0 ? STATUS.DIRTY
+ : STATUS.CLEAN;
+
+ // Collect or send telemetry data.
+ if (this.status == STATUS.DIRTY) {
+ this._telemetrySteps++;
+ }
+ else {
+ // Avoid reporting the common cases where the database is clean, or
+ // a single step is needed.
+ if (oldStatus == STATUS.DIRTY) {
+ try {
+ Services.telemetry
+ .getHistogramById("PLACES_EXPIRATION_STEPS_TO_CLEAN2")
+ .add(this._telemetrySteps);
+ } catch (ex) {
+ Components.utils.reportError("Unable to report telemetry.");
+ }
+ }
+ this._telemetrySteps = 1;
+ }
+
+ delete this._expectedResultsCount;
+ }
+
+ // Dispatch a notification that expiration has finished.
+ Services.obs.notifyObservers(null, TOPIC_EXPIRATION_FINISHED, null);
+ }
+ },
+
+ // nsPlacesExpiration
+
+ _urisLimit: PREF_MAX_URIS_NOTSET,
+ _interval: PREF_INTERVAL_SECONDS_NOTSET,
+ _shuttingDown: false,
+
+ _status: STATUS.UNKNOWN,
+ set status(aNewStatus) {
+ if (aNewStatus != this._status) {
+ // If status changes we should restart the timer.
+ this._status = aNewStatus;
+ this._newTimer();
+ // If needed add/remove the cleanup step on idle. We want to expire on
+ // idle only if history is dirty, to preserve mobile devices batteries.
+ this.expireOnIdle = aNewStatus == STATUS.DIRTY;
+ }
+ return aNewStatus;
+ },
+ get status() {
+ return this._status;
+ },
+
+ _isIdleObserver: false,
+ _expireOnIdle: false,
+ set expireOnIdle(aExpireOnIdle) {
+ // Observe idle regardless aExpireOnIdle, since we always want to stop
+ // timed expiration on idle, to preserve mobile battery life.
+ if (!this._isIdleObserver && !this._shuttingDown) {
+ this._idle.addIdleObserver(this, IDLE_TIMEOUT_SECONDS);
+ this._isIdleObserver = true;
+ }
+ else if (this._isIdleObserver && this._shuttingDown) {
+ this._idle.removeIdleObserver(this, IDLE_TIMEOUT_SECONDS);
+ this._isIdleObserver = false;
+ }
+
+ // If running a debug expiration we need full control of what happens
+ // but idle cleanup could activate in the middle, since tinderboxes are
+ // permanently idle. That would cause unexpected oranges, so disable it.
+ if (this._debugLimit !== undefined)
+ this._expireOnIdle = false;
+ else
+ this._expireOnIdle = aExpireOnIdle;
+ return this._expireOnIdle;
+ },
+ get expireOnIdle() {
+ return this._expireOnIdle;
+ },
+
+ _loadPrefs: Task.async(function* () {
+ // Get the user's limit, if it was set.
+ try {
+ // We want to silently fail since getIntPref throws if it does not exist,
+ // and use a default to fallback to.
+ this._urisLimit = this._prefBranch.getIntPref(PREF_MAX_URIS);
+ } catch (ex) { /* User limit not set */ }
+
+ if (this._urisLimit < 0) {
+ // Some testing code expects a pref change to be synchronous, so
+ // temporarily set this to a large value, while we asynchronously update
+ // to the correct value.
+ this._urisLimit = 300000;
+
+ // The user didn't specify a custom limit, so we calculate the number of
+ // unique places that may fit an optimal database size on this hardware.
+ // Oldest pages over this threshold will be expired.
+ let memSizeBytes = MEMSIZE_FALLBACK_BYTES;
+ try {
+ // Limit the size on systems with small memory.
+ memSizeBytes = Services.sysinfo.getProperty("memsize");
+ } catch (ex) {}
+ if (memSizeBytes <= 0) {
+ memsize = MEMSIZE_FALLBACK_BYTES;
+ }
+
+ let diskAvailableBytes = DISKSIZE_FALLBACK_BYTES;
+ try {
+ // Protect against a full disk or tiny quota.
+ let dbFile = this._db.databaseFile;
+ dbFile.QueryInterface(Ci.nsILocalFile);
+ diskAvailableBytes = dbFile.diskSpaceAvailable;
+ } catch (ex) {}
+ if (diskAvailableBytes <= 0) {
+ diskAvailableBytes = DISKSIZE_FALLBACK_BYTES;
+ }
+
+ let optimalDatabaseSize = Math.min(
+ memSizeBytes * DATABASE_TO_MEMORY_PERC / 100,
+ diskAvailableBytes * DATABASE_TO_DISK_PERC / 100,
+ DATABASE_MAX_SIZE
+ );
+
+ // Calculate avg size of a URI in the database.
+ let db = yield PlacesUtils.promiseDBConnection();
+ let pageSize = (yield db.execute(`PRAGMA page_size`))[0].getResultByIndex(0);
+ let pageCount = (yield db.execute(`PRAGMA page_count`))[0].getResultByIndex(0);
+ let freelistCount = (yield db.execute(`PRAGMA freelist_count`))[0].getResultByIndex(0);
+ let dbSize = (pageCount - freelistCount) * pageSize;
+ let uriCount = (yield db.execute(`SELECT count(*) FROM moz_places`))[0].getResultByIndex(0);
+ let avgURISize = Math.ceil(dbSize / uriCount);
+ // For new profiles this value may be too large, due to the Sqlite header,
+ // or Infinity when there are no pages. Thus we must limit it.
+ if (avgURISize > (URIENTRY_AVG_SIZE * 3)) {
+ avgURISize = URIENTRY_AVG_SIZE;
+ }
+ this._urisLimit = Math.ceil(optimalDatabaseSize / avgURISize);
+ }
+
+ // Expose the calculated limit to other components.
+ this._prefBranch.setIntPref(PREF_READONLY_CALCULATED_MAX_URIS,
+ this._urisLimit);
+
+ // Get the expiration interval value.
+ try {
+ // We want to silently fail since getIntPref throws if it does not exist,
+ // and use a default to fallback to.
+ this._interval = this._prefBranch.getIntPref(PREF_INTERVAL_SECONDS);
+ } catch (ex) { /* User interval not set */ }
+ if (this._interval <= 0) {
+ this._interval = PREF_INTERVAL_SECONDS_NOTSET;
+ }
+ }),
+
+ /**
+ * Evaluates the real number of pages in the database and the value currently
+ * used by the SQLite query planner.
+ *
+ * @param aCallback
+ * invoked on success, function (aPagesCount, aStatsCount).
+ */
+ _getPagesStats: function PEX__getPagesStats(aCallback) {
+ if (!this._cachedStatements["LIMIT_COUNT"]) {
+ this._cachedStatements["LIMIT_COUNT"] = this._db.createAsyncStatement(
+ `SELECT (SELECT COUNT(*) FROM moz_places),
+ (SELECT SUBSTR(stat,1,LENGTH(stat)-2) FROM sqlite_stat1
+ WHERE idx = 'moz_places_url_uniqueindex')`
+ );
+ }
+ this._cachedStatements["LIMIT_COUNT"].executeAsync({
+ _pagesCount: 0,
+ _statsCount: 0,
+ handleResult: function(aResults) {
+ let row = aResults.getNextRow();
+ this._pagesCount = row.getResultByIndex(0);
+ this._statsCount = row.getResultByIndex(1);
+ },
+ handleCompletion: function (aReason) {
+ if (aReason == Ci.mozIStorageStatementCallback.REASON_FINISHED) {
+ aCallback(this._pagesCount, this._statsCount);
+ }
+ },
+ handleError: function(aError) {
+ Cu.reportError("Async statement execution returned with '" +
+ aError.result + "', '" + aError.message + "'");
+ }
+ });
+ },
+
+ /**
+ * Execute async statements to expire with the specified queries.
+ *
+ * @param aAction
+ * The ACTION we are expiring for. See the ACTION const for values.
+ * @param aLimit
+ * Whether to use small, large or no limits when expiring. See the
+ * LIMIT const for values.
+ */
+ _expireWithActionAndLimit:
+ function PEX__expireWithActionAndLimit(aAction, aLimit)
+ {
+ // Skip expiration during batch mode.
+ if (this._inBatchMode)
+ return;
+ // Don't try to further expire after shutdown.
+ if (this._shuttingDown && aAction != ACTION.SHUTDOWN_DIRTY) {
+ return;
+ }
+
+ let boundStatements = [];
+ for (let queryType in EXPIRATION_QUERIES) {
+ if (EXPIRATION_QUERIES[queryType].actions & aAction)
+ boundStatements.push(this._getBoundStatement(queryType, aLimit, aAction));
+ }
+
+ // Execute statements asynchronously in a transaction.
+ this._db.executeAsync(boundStatements, boundStatements.length, this);
+ },
+
+ /**
+ * Finalizes all of our mozIStorageStatements so we can properly close the
+ * database.
+ */
+ _finalizeInternalStatements: function PEX__finalizeInternalStatements()
+ {
+ for (let queryType in this._cachedStatements) {
+ let stmt = this._cachedStatements[queryType];
+ stmt.finalize();
+ }
+ },
+
+ /**
+ * Generate the statement used for expiration.
+ *
+ * @param aQueryType
+ * Type of the query to build statement for.
+ * @param aLimit
+ * Whether to use small, large or no limits when expiring. See the
+ * LIMIT const for values.
+ * @param aAction
+ * Current action causing the expiration. See the ACTION const.
+ */
+ _cachedStatements: {},
+ _getBoundStatement: function PEX__getBoundStatement(aQueryType, aLimit, aAction)
+ {
+ // Statements creation can be expensive, so we want to cache them.
+ let stmt = this._cachedStatements[aQueryType];
+ if (stmt === undefined) {
+ stmt = this._cachedStatements[aQueryType] =
+ this._db.createAsyncStatement(EXPIRATION_QUERIES[aQueryType].sql);
+ }
+
+ let baseLimit;
+ switch (aLimit) {
+ case LIMIT.UNLIMITED:
+ baseLimit = -1;
+ break;
+ case LIMIT.SMALL:
+ baseLimit = EXPIRE_LIMIT_PER_STEP;
+ break;
+ case LIMIT.LARGE:
+ baseLimit = EXPIRE_LIMIT_PER_STEP * EXPIRE_LIMIT_PER_LARGE_STEP_MULTIPLIER;
+ break;
+ case LIMIT.DEBUG:
+ baseLimit = this._debugLimit;
+ break;
+ }
+ if (this.status == STATUS.DIRTY && aAction != ACTION.DEBUG &&
+ baseLimit > 0) {
+ baseLimit *= EXPIRE_AGGRESSIVITY_MULTIPLIER;
+ }
+
+ // Bind the appropriate parameters.
+ let params = stmt.params;
+ switch (aQueryType) {
+ case "QUERY_FIND_EXOTIC_VISITS_TO_EXPIRE":
+ // Avoid expiring all visits in case of an unlimited debug expiration,
+ // just remove orphans instead.
+ params.limit_visits =
+ aLimit == LIMIT.DEBUG && baseLimit == -1 ? 0 : baseLimit;
+ break;
+ case "QUERY_FIND_VISITS_TO_EXPIRE":
+ params.max_uris = this._urisLimit;
+ // Avoid expiring all visits in case of an unlimited debug expiration,
+ // just remove orphans instead.
+ params.limit_visits =
+ aLimit == LIMIT.DEBUG && baseLimit == -1 ? 0 : baseLimit;
+ break;
+ case "QUERY_FIND_URIS_TO_EXPIRE":
+ params.limit_uris = baseLimit;
+ break;
+ case "QUERY_SILENT_EXPIRE_ORPHAN_URIS":
+ params.limit_uris = baseLimit;
+ break;
+ case "QUERY_EXPIRE_FAVICONS":
+ params.limit_favicons = baseLimit;
+ break;
+ case "QUERY_EXPIRE_ANNOS":
+ // Each page may have multiple annos.
+ params.limit_annos = baseLimit * EXPIRE_AGGRESSIVITY_MULTIPLIER;
+ break;
+ case "QUERY_EXPIRE_ANNOS_WITH_POLICY":
+ case "QUERY_EXPIRE_ITEMS_ANNOS_WITH_POLICY":
+ let microNow = Date.now() * 1000;
+ ANNOS_EXPIRE_POLICIES.forEach(function(policy) {
+ params[policy.bind] = policy.type;
+ params[policy.bind + "_time"] = microNow - policy.time;
+ });
+ break;
+ case "QUERY_EXPIRE_ANNOS_WITH_HISTORY":
+ params.expire_with_history = Ci.nsIAnnotationService.EXPIRE_WITH_HISTORY;
+ break;
+ case "QUERY_EXPIRE_ITEMS_ANNOS":
+ params.limit_annos = baseLimit;
+ break;
+ case "QUERY_EXPIRE_ANNO_ATTRIBUTES":
+ params.limit_annos = baseLimit;
+ break;
+ case "QUERY_EXPIRE_INPUTHISTORY":
+ params.limit_inputhistory = baseLimit;
+ break;
+ case "QUERY_EXPIRE_ANNOS_SESSION":
+ case "QUERY_EXPIRE_ITEMS_ANNOS_SESSION":
+ params.expire_session = Ci.nsIAnnotationService.EXPIRE_SESSION;
+ break;
+ }
+
+ return stmt;
+ },
+
+ /**
+ * Creates a new timer based on this._interval.
+ *
+ * @return a REPEATING_SLACK nsITimer that runs every this._interval.
+ */
+ _newTimer: function PEX__newTimer()
+ {
+ if (this._timer)
+ this._timer.cancel();
+ if (this._shuttingDown)
+ return undefined;
+ let interval = this.status != STATUS.DIRTY ?
+ this._interval * EXPIRE_AGGRESSIVITY_MULTIPLIER : this._interval;
+
+ let timer = Cc["@mozilla.org/timer;1"].createInstance(Ci.nsITimer);
+ timer.initWithCallback(this, interval * 1000,
+ Ci.nsITimer.TYPE_REPEATING_SLACK);
+ if (this._testingMode) {
+ Services.obs.notifyObservers(null, TOPIC_TEST_INTERVAL_CHANGED,
+ interval);
+ }
+ return this._timer = timer;
+ },
+
+ // nsISupports
+
+ classID: Components.ID("705a423f-2f69-42f3-b9fe-1517e0dee56f"),
+
+ _xpcom_factory: XPCOMUtils.generateSingletonFactory(nsPlacesExpiration),
+
+ QueryInterface: XPCOMUtils.generateQI([
+ Ci.nsIObserver
+ , Ci.nsINavHistoryObserver
+ , Ci.nsITimerCallback
+ , Ci.mozIStorageStatementCallback
+ , Ci.nsISupportsWeakReference
+ ])
+};
+
+// Module Registration
+
+var components = [nsPlacesExpiration];
+this.NSGetFactory = XPCOMUtils.generateNSGetFactory(components);