1 files changed, 44 insertions, 0 deletions
diff --git a/event.go b/event.go
new file mode 100644
index 0000000..d238834
--- /dev/null
+++ b/event.go
@@ -0,0 +1,44 @@
+package main
+
+import (
+	"sync/atomic"
+	"time"
+)
+
+type Event struct {
+	guard    int32
+	next     time.Time
+	interval time.Duration
+	C        chan struct{}
+}
+
+func newEvent(interval time.Duration) *Event {
+	return &Event{
+		guard:    0,
+		next:     time.Now(),
+		interval: interval,
+		C:        make(chan struct{}, 1),
+	}
+}
+
+func (e *Event) Clear() {
+	select {
+	case <-e.C:
+	default:
+	}
+}
+
+func (e *Event) Fire() {
+	if e == nil || atomic.SwapInt32(&e.guard, 1) != 0 {
+		return
+	}
+	now := time.Now()
+	if e.next.After(now) {
+		select {
+		case e.C <- struct{}{}:
+		default:
+		}
+		e.next = now.Add(e.interval)
+	}
+	atomic.StoreInt32(&e.guard, 0)
+}