Initial QSfera import

Server/vendor/github.com/desertbit/timer/timer.go

@@ -0,0 +1,79 @@
+// Package timer is a Go timer implementation with a fixed Reset behavior.
+package timer
+
+import (
+	"time"
+)
+
+// The Timer type represents a single event. When the Timer expires,
+// the current time will be sent on C, unless the Timer was created by AfterFunc.
+// A Timer must be created with NewTimer. NewStoppedTimer or AfterFunc.
+type Timer struct {
+	C <-chan time.Time
+
+	i    int   // heap index.
+	when int64 // Timer wakes up at when.
+
+	// f is called in a locked context on timeout. This function must not block
+	// and must behave well-defined.
+	f func(t *time.Time)
+
+	// reset is called in a locked context. This function must not block
+	// and must behave well-defined.
+	reset func()
+}
+
+// NewTimer creates a new Timer that will send the current time on its
+// channel after at least duration d.
+func NewTimer(d time.Duration) *Timer {
+	t := NewStoppedTimer()
+	addTimer(t, d)
+	return t
+}
+
+// NewStoppedTimer creates a new stopped Timer.
+func NewStoppedTimer() *Timer {
+	c := make(chan time.Time, 1)
+	t := &Timer{
+		C: c,
+		f: func(t *time.Time) {
+			// Don't block.
+			select {
+			case c <- *t:
+			default:
+			}
+		},
+		reset: func() {
+			// Empty the channel if filled.
+			select {
+			case <-c:
+			default:
+			}
+		},
+	}
+	return t
+}
+
+// Stop prevents the Timer from firing.
+// It returns true if the call stops the timer,
+// false if the timer has already expired or been stopped.
+// Stop does not close the channel, to prevent a read from
+// the channel succeeding incorrectly.
+func (t *Timer) Stop() (wasActive bool) {
+	if t.f == nil {
+		panic("timer: Stop called on uninitialized Timer")
+	}
+	return delTimer(t)
+}
+
+// Reset changes the timer to expire after duration d.
+// It returns true if the timer had been active,
+// false if the timer had expired or been stopped.
+// The channel t.C is cleared and calling t.Reset() behaves as creating a
+// new Timer.
+func (t *Timer) Reset(d time.Duration) bool {
+	if t.f == nil {
+		panic("timer: Reset called on uninitialized Timer")
+	}
+	return resetTimer(t, d)
+}