TUN-528: Move cloudflared into a separate repo

h2mux/rtt.go

@@ -0,0 +1,29 @@
+package h2mux
+
+import (
+	"sync/atomic"
+)
+
+// PingTimestamp is an atomic interface around ping timestamping and signalling.
+type PingTimestamp struct {
+	ts     int64
+	signal Signal
+}
+
+func NewPingTimestamp() *PingTimestamp {
+	return &PingTimestamp{signal: NewSignal()}
+}
+
+func (pt *PingTimestamp) Set(v int64) {
+	if atomic.SwapInt64(&pt.ts, v) != 0 {
+		pt.signal.Signal()
+	}
+}
+
+func (pt *PingTimestamp) Get() int64 {
+	return atomic.SwapInt64(&pt.ts, 0)
+}
+
+func (pt *PingTimestamp) GetUpdateChan() <-chan struct{} {
+	return pt.signal.WaitChannel()
+}