added watchdog to restart librespot

server/streamreader/watchdog.h

@@ -0,0 +1,63 @@
+/***
+    This file is part of snapcast
+    Copyright (C) 2014-2016  Johannes Pohl
+
+    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 3 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, see <http://www.gnu.org/licenses/>.
+***/
+
+#ifndef WATCH_DOG_H
+#define WATCH_DOG_H
+
+#include <mutex>
+#include <thread>
+#include <memory>
+#include <atomic>
+#include <condition_variable>
+
+
+class Watchdog;
+
+
+class WatchdogListener
+{
+public:
+	virtual void onTimeout(const Watchdog* watchdog, size_t ms) = 0;
+};
+
+
+/// Watchdog
+class Watchdog
+{
+public:
+	Watchdog(WatchdogListener* listener = nullptr);
+	virtual ~Watchdog();
+
+	void start(size_t timeoutMs);
+	void stop();
+	void trigger();
+
+private:
+	WatchdogListener* listener_;
+	std::condition_variable cv_;
+	std::mutex mtx_;
+	std::unique_ptr<std::thread> thread_;
+	size_t timeoutMs_;
+	std::atomic<bool> active_;
+
+	void worker();
+};
+
+
+#endif
+