• Max Kellermann's avatar
    db/simple: mount points · e9a85aa4
    Max Kellermann authored
    A SimpleDatabase instance can now "mount" other Database instances at
    certain locations.  This is used to use a new SimpleDatabase instance
    for each storage mount (issued with the "mount" protocol command).
    Each such instance has its own database file, stored in the directory
    that is specified with the "cache_directory" option.
    e9a85aa4
Queue.hxx 1.77 KB
/*
 * Copyright (C) 2003-2014 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_QUEUE_HXX
#define MPD_UPDATE_QUEUE_HXX

#include "check.h"
#include "Compiler.h"

#include <string>
#include <list>

class SimpleDatabase;
class Storage;

struct UpdateQueueItem {
	SimpleDatabase *db;
	Storage *storage;

	std::string path_utf8;
	unsigned id;
	bool discard;

	UpdateQueueItem():id(0) {}

	UpdateQueueItem(SimpleDatabase &_db,
			Storage &_storage,
			const char *_path, bool _discard,
			unsigned _id)
		:db(&_db), storage(&_storage), path_utf8(_path),
		 id(_id), discard(_discard) {}

	bool IsDefined() const {
		return id != 0;
	}
};

class UpdateQueue {
	static constexpr unsigned MAX_UPDATE_QUEUE_SIZE = 32;

	std::list<UpdateQueueItem> update_queue;

public:
	gcc_nonnull_all
	bool Push(SimpleDatabase &db, Storage &storage,
		  const char *path, bool discard, unsigned id);

	UpdateQueueItem Pop();

	void Clear() {
		update_queue.clear();
	}

	gcc_nonnull_all
	void Erase(SimpleDatabase &db);

	gcc_nonnull_all
	void Erase(Storage &storage);
};

#endif