/* * Copyright 2003-2018 The Music Player Daemon Project * http://www.musicpd.org * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License along * with this program; if not, write to the Free Software Foundation, Inc., * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. */ #ifndef MPD_UPDATE_SERVICE_HXX #define MPD_UPDATE_SERVICE_HXX #include "Config.hxx" #include "Queue.hxx" #include "event/DeferEvent.hxx" #include "thread/Thread.hxx" #include "util/Compiler.h" class SimpleDatabase; class DatabaseListener; class UpdateWalk; class CompositeStorage; /** * This class manages the update queue and runs the update thread. */ class UpdateService final { const UpdateConfig config; DeferEvent defer; SimpleDatabase &db; CompositeStorage &storage; DatabaseListener &listener; bool modified; Thread update_thread; static constexpr unsigned update_task_id_max = 1 << 15; unsigned update_task_id = 0; UpdateQueue queue; UpdateQueueItem next; UpdateWalk *walk = nullptr; public: UpdateService(const ConfigData &_config, EventLoop &_loop, SimpleDatabase &_db, CompositeStorage &_storage, DatabaseListener &_listener); ~UpdateService(); auto &GetEventLoop() const noexcept { return defer.GetEventLoop(); } /** * Returns a non-zero job id when we are currently updating * the database. */ unsigned GetId() const { return next.id; } /** * Add this path to the database update queue. * * Throws on error * * @param path a path to update; if an empty string, * the whole music directory is updated * @return the job id */ gcc_nonnull_all unsigned Enqueue(const char *path, bool discard); /** * Clear the queue and cancel the current update. Does not * wait for the thread to exit. */ void CancelAllAsync(); /** * Cancel all updates for the given mount point. If an update * is already running for it, the method will wait for * cancellation to complete. */ void CancelMount(const char *uri); private: /* DeferEvent callback */ void RunDeferred() noexcept; /* the update thread */ void Task(); void StartThread(UpdateQueueItem &&i); unsigned GenerateId(); }; #endif