event/TimerEvent: add type alias for std::chrono::steady_clock::duration

src/event/Chrono.hxx

@@ -0,0 +1,36 @@
+/*
+ * Copyright 2003-2020 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_EVENT_CHRONO_HXX
+#define MPD_EVENT_CHRONO_HXX
+
+#include <chrono>
+
+namespace Event {
+
+/**
+ * The clock used by class #EventLoop and class #TimerEvent.
+ */
+using Clock = std::chrono::steady_clock;
+
+using Duration = Clock::duration;
+
+} // namespace Event
+
+#endif /* MAIN_NOTIFY_H */

src/event/Loop.cxx

@@ -122,7 +122,7 @@ EventLoop::RemoveIdle(IdleMonitor &i) noexcept
 }
 
 void
-EventLoop::AddTimer(TimerEvent &t, std::chrono::steady_clock::duration d) noexcept
+EventLoop::AddTimer(TimerEvent &t, Event::Duration d) noexcept
 {
 	assert(IsInside());
 
@@ -131,10 +131,10 @@ EventLoop::AddTimer(TimerEvent &t, std::chrono::steady_clock::duration d) noexce
 	again = true;
 }
 
-inline std::chrono::steady_clock::duration
+inline Event::Duration
 EventLoop::HandleTimers() noexcept
 {
-	std::chrono::steady_clock::duration timeout;
+	Event::Duration timeout;
 
 	while (!quit) {
 		auto i = timers.begin();
@@ -151,7 +151,7 @@ EventLoop::HandleTimers() noexcept
 		t.Run();
 	}
 
-	return std::chrono::steady_clock::duration(-1);
+	return Event::Duration(-1);
 }
 
 /**
@@ -160,7 +160,7 @@ EventLoop::HandleTimers() noexcept
  * value (= never times out) is translated to the magic value -1.
  */
 static constexpr int
-ExportTimeoutMS(std::chrono::steady_clock::duration timeout)
+ExportTimeoutMS(Event::Duration timeout)
 {
 	return timeout >= timeout.zero()
 		/* round up (+1) to avoid unnecessary wakeups */

src/event/Loop.hxx

@@ -20,6 +20,7 @@
 #ifndef MPD_EVENT_LOOP_HXX
 #define MPD_EVENT_LOOP_HXX
 
+#include "Chrono.hxx"
 #include "PollGroup.hxx"
 #include "WakeFD.hxx"
 #include "SocketMonitor.hxx"
@@ -91,7 +92,7 @@ class EventLoop final : SocketMonitor
 	std::unique_ptr<Uring::Manager> uring;
 #endif
 
-	std::chrono::steady_clock::time_point now = std::chrono::steady_clock::now();
+	Event::Clock::time_point now = Event::Clock::now();
 
 	/**
 	 * Is this #EventLoop alive, i.e. can events be scheduled?
@@ -140,9 +141,9 @@ public:
 	~EventLoop() noexcept;
 
 	/**
-	 * A caching wrapper for std::chrono::steady_clock::now().
+	 * A caching wrapper for Event::Clock::now().
 	 */
-	std::chrono::steady_clock::time_point GetTime() const {
+	auto GetTime() const {
 		assert(IsInside());
 
 		return now;
@@ -184,8 +185,7 @@ public:
 	void AddIdle(IdleMonitor &i) noexcept;
 	void RemoveIdle(IdleMonitor &i) noexcept;
 
-	void AddTimer(TimerEvent &t,
-		      std::chrono::steady_clock::duration d) noexcept;
+	void AddTimer(TimerEvent &t, Event::Duration d) noexcept;
 
 	/**
 	 * Schedule a call to DeferEvent::RunDeferred().
@@ -221,7 +221,7 @@ private:
 	 * duration until the next timer expires.  Returns a negative
 	 * duration if there is no timeout.
 	 */
-	std::chrono::steady_clock::duration HandleTimers() noexcept;
+	Event::Duration HandleTimers() noexcept;
 
 	bool OnSocketReady(unsigned flags) noexcept override;
 

src/event/MultiSocketMonitor.cxx

@@ -117,7 +117,7 @@ MultiSocketMonitor::Prepare() noexcept
 		/* if there was at least one file descriptor not
 		   supported by epoll, install a very short timeout
 		   because we assume it's always ready */
-		constexpr std::chrono::steady_clock::duration ready_timeout =
+		constexpr Event::Duration ready_timeout =
 			std::chrono::milliseconds(1);
 		if (timeout < timeout.zero() || timeout > ready_timeout)
 			timeout = ready_timeout;

src/event/MultiSocketMonitor.hxx

@@ -226,7 +226,7 @@ protected:
 	 *
 	 * @return timeout or a negative value for no timeout
 	 */
-	virtual std::chrono::steady_clock::duration PrepareSockets() noexcept = 0;
+	virtual Event::Duration PrepareSockets() noexcept = 0;
 
 	/**
 	 * At least one socket is ready or the timeout has expired.

src/event/TimerEvent.cxx

@@ -21,7 +21,7 @@
 #include "Loop.hxx"
 
 void
-TimerEvent::Schedule(std::chrono::steady_clock::duration d) noexcept
+TimerEvent::Schedule(Event::Duration d) noexcept
 {
 	Cancel();
 

src/event/TimerEvent.hxx

@@ -20,12 +20,11 @@
 #ifndef MPD_TIMER_EVENT_HXX
 #define MPD_TIMER_EVENT_HXX
 
+#include "Chrono.hxx"
 #include "util/BindMethod.hxx"
 
 #include <boost/intrusive/set_hook.hpp>
 
-#include <chrono>
-
 class EventLoop;
 
 /**
@@ -50,7 +49,7 @@ class TimerEvent final
 	 * When is this timer due?  This is only valid if IsActive()
 	 * returns true.
 	 */
-	std::chrono::steady_clock::time_point due;
+	Event::Clock::time_point due;
 
 public:
 	TimerEvent(EventLoop &_loop, Callback _callback) noexcept
@@ -65,7 +64,7 @@ public:
 		return is_linked();
 	}
 
-	void Schedule(std::chrono::steady_clock::duration d) noexcept;
+	void Schedule(Event::Duration d) noexcept;
 
 	void Cancel() noexcept {
 		unlink();