No more blocking on multiple Stop()

common/repeat_timer.go

@@ -16,8 +16,9 @@ type RepeatTimer struct {
 	output chan<- time.Time
 	input  chan repeatCommand
 
-	dur   time.Duration
+	dur     time.Duration
-	timer *time.Timer
+	timer   *time.Timer
+	stopped bool
 }
 
 type repeatCommand int32
@@ -50,43 +51,42 @@ func (t *RepeatTimer) Reset() {
 // For ease of .Stop()'ing services before .Start()'ing them,
 // we ignore .Stop()'s on nil RepeatTimers.
 func (t *RepeatTimer) Stop() bool {
-	if t == nil {
+	if t == nil || t.stopped {
 		return false
 	}
 	t.input <- RQuit
+	t.stopped = true
 	return true
 }
 
 func (t *RepeatTimer) run() {
-	for {
+	done := false
-		fmt.Println("for")
+	for !done {
 		select {
 		case cmd := <-t.input:
 			// stop goroutine if the input says so
 			// don't close channels, as closed channels mess up select reads
-			if t.processInput(cmd) {
+			done = t.processInput(cmd)
-				t.timer.Stop()
-				return
-			}
 		case <-t.timer.C:
-			fmt.Println("tick")
 			// send if not blocked, then start the next tick
-			// for blocking send, just
-			// t.output <- time.Now()
 			t.trySend()
 			t.timer.Reset(t.dur)
 		}
 	}
+	fmt.Println("end run")
 }
 
 // trySend performs non-blocking send on t.Ch
 func (t *RepeatTimer) trySend() {
 	// TODO: this was blocking in previous version (t.Ch <- t_)
 	// should I use that behavior unstead of unblocking as per throttle?
-	select {
+
-	case t.output <- time.Now():
+	// select {
-	default:
+	// case t.output <- time.Now():
-	}
+	// default:
+	// }
+
+	t.output <- time.Now()
 }
 
 // all modifications of the internal state of ThrottleTimer
@@ -98,6 +98,7 @@ func (t *RepeatTimer) processInput(cmd repeatCommand) (shutdown bool) {
 	case Reset:
 		t.timer.Reset(t.dur)
 	case RQuit:
+		fmt.Println("got quit")
 		t.timer.Stop()
 		shutdown = true
 	default:

common/repeat_timer_test.go

@@ -73,6 +73,6 @@ func TestRepeat(test *testing.T) {
 	time.Sleep(delay(7))
 	assert.Equal(6, c.Count())
 
-	// close channel to stop counter
+	// extra calls to stop don't block
 	t.Stop()
 }

common/throttle_timer.go

@@ -17,8 +17,9 @@ type ThrottleTimer struct {
 	output chan<- struct{}
 	dur    time.Duration
 
-	timer *time.Timer
+	timer   *time.Timer
-	isSet bool
+	isSet   bool
+	stopped bool
 }
 
 type throttleCommand int32
@@ -82,6 +83,7 @@ func (t *ThrottleTimer) processInput(cmd throttleCommand) (shutdown bool) {
 			t.timer.Reset(t.dur)
 		}
 	case TQuit:
+		t.stopped = true
 		shutdown = true
 		fallthrough
 	case Unset:
@@ -119,7 +121,7 @@ func (t *ThrottleTimer) Unset() {
 // For ease of stopping services before starting them, we ignore Stop on nil
 // ThrottleTimers.
 func (t *ThrottleTimer) Stop() bool {
-	if t == nil {
+	if t == nil || t.stopped {
 		return false
 	}
 	t.input <- TQuit

common/throttle_timer_test.go

@@ -95,4 +95,9 @@ func TestThrottle(test *testing.T) {
 
 	stopped := t.Stop()
 	assert.True(stopped)
+	time.Sleep(longwait)
+	assert.Equal(5, c.Count())
+
+	// extra calls to stop don't block
+	t.Stop()
 }