From 7348d1e71739bb7a5052375e6e918e92f5d1d6b0 Mon Sep 17 00:00:00 2001
From: cryptocode <stein@nano.org>
Date: Thu, 12 Mar 2020 15:22:55 +0100
Subject: [PATCH] Update tick count in timer::update (#2655)

* Update tick count in timer::update

* Return ticks from restart
---
 nano/core_test/timer.cpp |  2 ++
 nano/lib/timer.cpp       | 17 +++++++++++++----
 nano/lib/timer.hpp       |  8 +++++---
 3 files changed, 20 insertions(+), 7 deletions(-)

diff --git a/nano/core_test/timer.cpp b/nano/core_test/timer.cpp
index ffd65f46..1aa29739 100644
--- a/nano/core_test/timer.cpp
+++ b/nano/core_test/timer.cpp
@@ -42,6 +42,8 @@ TEST (timer, measure_and_compare)
 	ASSERT_LT (t1.since_start (), 200ms);
 	ASSERT_GT (t1.since_start (), 10ms);
 	ASSERT_GE (t1.stop (), 50ms);
+	std::this_thread::sleep_for (50ms);
+	ASSERT_GT (t1.restart (), 10ms);
 }
 
 TEST (timer, cummulative_child)
diff --git a/nano/lib/timer.cpp b/nano/lib/timer.cpp
index ed2988a2..2acd1881 100644
--- a/nano/lib/timer.cpp
+++ b/nano/lib/timer.cpp
@@ -97,12 +97,14 @@ void nano::timer<UNIT, CLOCK>::start ()
 }
 
 template <typename UNIT, typename CLOCK>
-void nano::timer<UNIT, CLOCK>::restart ()
+UNIT nano::timer<UNIT, CLOCK>::restart ()
 {
+	auto current = ticks;
 	state = nano::timer_state::started;
 	begin = CLOCK::now ();
 	ticks = UNIT::zero ();
 	measurements = 0;
+	return current;
 }
 
 template <typename UNIT, typename CLOCK>
@@ -112,20 +114,27 @@ UNIT nano::timer<UNIT, CLOCK>::pause ()
 	return stop ();
 }
 
+template <typename UNIT, typename CLOCK>
+void nano::timer<UNIT, CLOCK>::update_ticks ()
+{
+	auto end = CLOCK::now ();
+	ticks += std::chrono::duration_cast<UNIT> (end - begin);
+}
+
 template <typename UNIT, typename CLOCK>
 UNIT nano::timer<UNIT, CLOCK>::stop ()
 {
 	debug_assert (state == nano::timer_state::started);
 	state = nano::timer_state::stopped;
 
-	auto end = CLOCK::now ();
-	ticks += std::chrono::duration_cast<UNIT> (end - begin);
+	update_ticks ();
 	return ticks;
 }
 
 template <typename UNIT, typename CLOCK>
-UNIT nano::timer<UNIT, CLOCK>::value () const
+UNIT nano::timer<UNIT, CLOCK>::value ()
 {
+	update_ticks ();
 	return ticks;
 }
 
diff --git a/nano/lib/timer.hpp b/nano/lib/timer.hpp
index 61c201d3..423d6f6f 100644
--- a/nano/lib/timer.hpp
+++ b/nano/lib/timer.hpp
@@ -42,8 +42,9 @@ public:
 	/**
 	 * Restarts the timer by setting start time to current time and resetting tick count.
 	 * This can be called in any timer state.
+	 * @return duration
 	 */
-	void restart ();
+	UNIT restart ();
 
 	/**
 	 * Stops the timer and increases the measurement count. A timer can be started and paused
@@ -59,9 +60,9 @@ public:
 	UNIT stop ();
 
 	/**
-	 * Return current tick count.
+	 * Updates and returns current tick count.
 	 */
-	UNIT value () const;
+	UNIT value ();
 
 	/** Returns the duration in UNIT since the timer was last started. */
 	UNIT since_start () const;
@@ -94,5 +95,6 @@ private:
 	UNIT ticks{ 0 };
 	UNIT minimum{ UNIT::zero () };
 	unsigned measurements{ 0 };
+	void update_ticks ();
 };
 }