[timers] Add wait method for fibers

Author: salkinium

src/modm/processing/timer/periodic_timer.hpp

@@ -73,6 +73,17 @@ class GenericPeriodicTimer : public GenericTimeout<Clock, Duration>
 		}
 		return 0;
 	}
+
+	/// Wait until the periodic timer expired.
+	/// @warning This is a blocking call! Inside a fiber, this function yields.
+	/// @return the number of missed periods
+	size_t
+	wait()
+	{
+		size_t count{};
+		modm::this_fiber::poll([&]{ return (count = execute()); });
+		return count;
+	}
 };
 
 /**

src/modm/processing/timer/timeout.hpp

@@ -19,6 +19,7 @@
 #include <modm/math/utils/arithmetic_traits.hpp>
 #include <modm/architecture/interface/clock.hpp>
 #include <modm/architecture/interface/assert.hpp>
+#include <modm/processing/fiber.hpp>
 
 namespace modm
 {
@@ -108,6 +109,11 @@ class GenericTimeout
 	bool
 	execute();
 
+	/// Wait until the timeout expired.
+	/// @warning This is a blocking call! Inside a fiber, this function yields.
+	void
+	wait();
+
 protected:
 	bool
 	checkExpiration() const;

src/modm/processing/timer/timeout_impl.hpp

@@ -126,6 +126,13 @@ modm::GenericTimeout<Clock, Duration>::isExpired() const
 	return state() == TimerState::Expired;
 }
 
+template< class Clock, class Duration >
+void
+modm::GenericTimeout<Clock, Duration>::wait()
+{
+	modm::this_fiber::poll([this]{ return not execute(); });
+}
+
 // ----------------------------------------------------------------------------
 template< class Clock, class Duration >
 bool