X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=quittable_sleeper.h;fp=quittable_sleeper.h;h=ba00e73b1184e9d388c04867b080773247547820;hb=f07adb19f0e2571bf4894ec57e6fcfe4a3e5fd95;hp=0000000000000000000000000000000000000000;hpb=b6089b76678e76271616131672c5ba454a5d336d;p=nageru

diff --git a/quittable_sleeper.h b/quittable_sleeper.h
new file mode 100644
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--- /dev/null
+++ b/quittable_sleeper.h
@@ -0,0 +1,59 @@
+#ifndef _QUITTABLE_SLEEPER
+#define _QUITTABLE_SLEEPER 1
+
+// A class that assists with fast shutdown of threads. You can set
+// a flag that says the thread should quit, which it can then check
+// in a loop -- and if the thread sleeps (using the sleep_* functions
+// on the class), that sleep will immediately be aborted.
+//
+// All member functions on this class are thread-safe.
+
+#include <chrono>
+#include <mutex>
+
+class QuittableSleeper {
+public:
+	void quit()
+	{
+		std::lock_guard<std::mutex> l(mu);
+		should_quit_var = true;
+		quit_cond.notify_all();
+	}
+
+	void unquit()
+	{
+		std::lock_guard<std::mutex> l(mu);
+		should_quit_var = false;
+	}
+
+	bool should_quit() const
+	{
+		std::lock_guard<std::mutex> l(mu);
+		return should_quit_var;
+	}
+
+	template<class Rep, class Period>
+	void sleep_for(const std::chrono::duration<Rep, Period> &duration)
+	{
+		std::chrono::steady_clock::time_point t =
+			std::chrono::steady_clock::now() +
+			std::chrono::duration_cast<std::chrono::steady_clock::duration>(duration);
+		sleep_until(t);
+	}
+
+	template<class Clock, class Duration>
+	void sleep_until(const std::chrono::time_point<Clock, Duration> &t)
+	{
+		std::unique_lock<std::mutex> lock(mu);
+		quit_cond.wait_until(lock, t, [this]{
+			return should_quit_var;
+		});
+	}
+
+private:
+	mutable std::mutex mu;
+	bool should_quit_var = false;
+	std::condition_variable quit_cond;
+};
+
+#endif  // !defined(_QUITTABLE_SLEEPER)