2 Copyright (C) 2018 Carl Hetherington <cth@carlh.net>
4 This file is part of DCP-o-matic.
6 DCP-o-matic is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2 of the License, or
9 (at your option) any later version.
11 DCP-o-matic is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with DCP-o-matic. If not, see <http://www.gnu.org/licenses/>.
21 /** @file src/lib/checker.h
22 * @brief Checker class.
25 #ifndef DCPOMATIC_CHECKER_H
26 #define DCPOMATIC_CHECKER_H
28 #include "signaller.h"
29 #include <boost/signals2.hpp>
31 /** Parent for classes which check some condition every so often and signal
32 * when the state of the condition changes.
34 class Checker : public Signaller, public boost::noncopyable
43 /** Emitted when the state of our condition changes */
44 boost::signals2::signal<void (void)> StateChanged;
50 /** @return true if the condition is `ok', otherwise false */
51 virtual bool check () const = 0;
57 boost::thread* _thread;
58 mutable boost::mutex _mutex;
61 /** check period in seconds */