Initial QSfera import

Server/vendor/github.com/jonboulle/clockwork/ticker.go

@@ -0,0 +1,71 @@
+package clockwork
+
+import "time"
+
+// Ticker provides an interface which can be used instead of directly using
+// [time.Ticker]. The real-time ticker t provides ticks through t.C which
+// becomes t.Chan() to make this channel requirement definable in this
+// interface.
+type Ticker interface {
+	Chan() <-chan time.Time
+	Reset(d time.Duration)
+	Stop()
+}
+
+type realTicker struct{ *time.Ticker }
+
+func (r realTicker) Chan() <-chan time.Time {
+	return r.C
+}
+
+type fakeTicker struct {
+	// The channel associated with the firer, used to send expiration times.
+	c chan time.Time
+
+	// The time when the ticker expires. Only meaningful if the ticker is currently
+	// one of a FakeClock's waiters.
+	exp time.Time
+
+	// reset and stop provide the implementation of the respective exported
+	// functions.
+	reset func(d time.Duration)
+	stop  func()
+
+	// The duration of the ticker.
+	d time.Duration
+}
+
+func newFakeTicker(fc *FakeClock, d time.Duration) *fakeTicker {
+	var ft *fakeTicker
+	ft = &fakeTicker{
+		c: make(chan time.Time, 1),
+		d: d,
+		reset: func(d time.Duration) {
+			fc.l.Lock()
+			defer fc.l.Unlock()
+			ft.d = d
+			fc.setExpirer(ft, d)
+		},
+		stop: func() { fc.stop(ft) },
+	}
+	return ft
+}
+
+func (f *fakeTicker) Chan() <-chan time.Time { return f.c }
+
+func (f *fakeTicker) Reset(d time.Duration) { f.reset(d) }
+
+func (f *fakeTicker) Stop() { f.stop() }
+
+func (f *fakeTicker) expire(now time.Time) *time.Duration {
+	// Never block on expiration.
+	select {
+	case f.c <- now:
+	default:
+	}
+	return &f.d
+}
+
+func (f *fakeTicker) expiration() time.Time { return f.exp }
+
+func (f *fakeTicker) setExpiration(t time.Time) { f.exp = t }