implement a send queue to send packet asynchronously

send_queue.go

@@ -0,0 +1,39 @@
+package quic
+
+type sendQueue struct {
+	queue     chan *packedPacket
+	closeChan chan struct{}
+	conn      connection
+}
+
+func newSendQueue(conn connection) *sendQueue {
+	s := &sendQueue{
+		conn:      conn,
+		closeChan: make(chan struct{}),
+		queue:     make(chan *packedPacket, 1),
+	}
+	return s
+}
+
+func (h *sendQueue) Send(p *packedPacket) {
+	h.queue <- p
+}
+
+func (h *sendQueue) Run() error {
+	var p *packedPacket
+	for {
+		select {
+		case <-h.closeChan:
+			return nil
+		case p = <-h.queue:
+		}
+		if err := h.conn.Write(p.raw); err != nil {
+			return err
+		}
+		p.buffer.Release()
+	}
+}
+
+func (h *sendQueue) Close() {
+	close(h.closeChan)
+}