fix EM.stop latency when timers exist (closes eventmachine#426)

Author: tmm1

ext/em.cpp

@@ -687,7 +687,7 @@ EventMachine_t::_TimeTilNextEvent
 
 timeval EventMachine_t::_TimeTilNextEvent()
 {
-	// 29jul11: Changed calculation base from MyCurrentLoopTime to the 
+	// 29jul11: Changed calculation base from MyCurrentLoopTime to the
 	// real time. As MyCurrentLoopTime is set at the beginning of an
 	// iteration and this calculation is done at the end, evenmachine
 	// will potentially oversleep by the amount of time the iteration
@@ -709,10 +709,12 @@ timeval EventMachine_t::_TimeTilNextEvent()
 	if (!NewDescriptors.empty() || !ModifiedDescriptors.empty()) {
 		next_event = current_time;
 	}
-	
+
 	timeval tv;
 
-	if (next_event == 0 || NumCloseScheduled > 0) {
+	if (NumCloseScheduled > 0 || bTerminateSignalReceived) {
+		tv.tv_sec = tv.tv_usec = 0;
+	} else if (next_event == 0) {
 		tv = Quantum;
 	} else {
 		if (next_event > current_time) {