michael@0: /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
michael@0:  * vim: sw=2 ts=2 et lcs=trail\:.,tab\:>~ :
michael@0:  * This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: #include "nsISupports.idl"
michael@0: 
michael@0: interface mozIStorageConnection;
michael@0: 
michael@0: /**
michael@0:  * This interface contains the information that the Storage service needs to
michael@0:  * vacuum a database.  This interface is created as a service through the
michael@0:  * category manager with the category "vacuum-participant".
michael@0:  * Please see https://developer.mozilla.org/en/mozIStorageVacuumParticipant for
michael@0:  * more information.
michael@0:  */
michael@0: [scriptable, uuid(8f367508-1d9a-4d3f-be0c-ac11b6dd7dbf)]
michael@0: interface mozIStorageVacuumParticipant : nsISupports {
michael@0:   /**
michael@0:    * The expected page size in bytes for the database.  The vacuum manager will
michael@0:    * try to correct the page size during idle based on this value.
michael@0:    *
michael@0:    * @note If the database is using the WAL journal mode, the page size won't
michael@0:   *        be changed to the requested value.  See bug 634374.
michael@0:    * @note Valid page size values are powers of 2 between 512 and 65536.
michael@0:    *       The suggested value is mozIStorageConnection::defaultPageSize.
michael@0:    */
michael@0:   readonly attribute long expectedDatabasePageSize;
michael@0: 
michael@0:   /**
michael@0:    * Connection to the database file to be vacuumed.
michael@0:    */
michael@0:   readonly attribute mozIStorageConnection databaseConnection;
michael@0: 
michael@0:   /**
michael@0:    * Notifies when a vacuum operation begins.  Listeners should avoid using the
michael@0:    * database till onEndVacuum is received.
michael@0:    *
michael@0:    * @return true to proceed with the vacuum, false if the participant wants to
michael@0:    *         opt-out for now, it will be retried later.  Useful when participant
michael@0:    *         is running some other heavy operation that can't be interrupted.
michael@0:    *
michael@0:    * @note When a vacuum operation starts or ends it will also dispatch a global
michael@0:    *       "heavy-io-task" notification through the observer service with the
michael@0:    *       data argument being either "vacuum-begin" or "vacuum-end".
michael@0:    */
michael@0:   boolean onBeginVacuum();
michael@0: 
michael@0:   /**
michael@0:    * Notifies when a vacuum operation ends.
michael@0:    *
michael@0:    * @param aSucceeded
michael@0:    *        reports if the vacuum succeeded or failed.
michael@0:    */
michael@0:   void onEndVacuum(in boolean aSucceeded);
michael@0: };