Upgraded Counter

counter.go

@@ -18,20 +18,22 @@ type (
 
 		mutex     sync.Mutex
 		stream    chan uint
-		streaming bool
+		streaming *sync.Cond
 	}
 )
 
-func NewCounter(wi, ri uint) Counter {
-	c := Counter{
+func NewCounter(wi, ri uint) *Counter {
+	m := &sync.Mutex{}
+	m.Lock()
+
+	c := &Counter{
 		WriteIndex: wi,
 		ReadIndex:  ri,
 		stream:     make(chan uint),
-		streaming:  false,
-	}
-	if c.Distance() > 0 {
-		go c.Stream()
+		streaming:  sync.NewCond(m),
 	}
+
+	go c.Stream()
 	return c
 }
 
@@ -42,9 +44,7 @@ func (c *Counter) Write(proc func(i uint) bool) {
 	ok := proc(c.WriteIndex + 1)
 	if ok {
 		c.WriteIndex++
-		if !c.streaming {
-			go c.Stream()
-		}
+		c.streaming.Signal()
 	}
 }
 
@@ -61,10 +61,12 @@ func (c *Counter) Distance() uint {
 }
 
 func (c *Counter) Stream() {
-	c.streaming = true
-	for c.WriteIndex > c.ReadIndex {
+	for {
+		if c.Distance() == 0 {
+			c.streaming.Wait()
+		}
+
 		c.stream <- c.ReadIndex + 1
 		c.ReadIndex++
 	}
-	c.streaming = false
 }