channel.go
func (ch *Channel) serve() {
	acceptBackoff := 0 * time.Millisecond

	for {
		netConn, err := ch.mutable.l.Accept()
		if err != nil {
			// Backoff from new accepts if this is a temporary error
			if ne, ok := err.(net.Error); ok && ne.Temporary() {
				if acceptBackoff == 0 {
					acceptBackoff = 5 * time.Millisecond
				} else {
					acceptBackoff *= 2
				}
				if max := 1 * time.Second; acceptBackoff > max {
					acceptBackoff = max
				}
				ch.log.WithFields(
					ErrField(err),
					LogField{"backoff", acceptBackoff},
				).Warn("Accept error, will wait and retry.")
				time.Sleep(acceptBackoff)
				continue
			} else {
				// Only log an error if this didn't happen due to a Close.
				if ch.State() >= ChannelStartClose {
					return
				}
				ch.log.WithFields(ErrField(err)).Fatal("Unrecoverable accept error, closing server.")
				return
			}
		}

		acceptBackoff = 0

		// Perform the connection handshake in a background goroutine.
		go func() {
			// Register the connection in the peer once the channel is set up.
			events := connectionEvents{
				OnActive:           ch.inboundConnectionActive,
				OnCloseStateChange: ch.connectionCloseStateChange,
				OnExchangeUpdated:  ch.exchangeUpdated,
			}
			if _, err := ch.inboundHandshake(context.Background(), netConn, events); err != nil {
				netConn.Close()
			}
		}()
	}
}
func (ch *Channel) serve() {
	acceptBackoff := 0 * time.Millisecond

	for {
		netConn, err := ch.mutable.l.Accept()
		if err != nil {
			// Backoff from new accepts if this is a temporary error
			if ne, ok := err.(net.Error); ok && ne.Temporary() {
				if acceptBackoff == 0 {
					acceptBackoff = 5 * time.Millisecond
				} else {
					acceptBackoff *= 2
				}
				if max := 1 * time.Second; acceptBackoff > max {
					acceptBackoff = max
				}
				ch.log.WithFields(
					ErrField(err),
					LogField{"backoff", acceptBackoff},
				).Warn("Accept error, will wait and retry.")
				time.Sleep(acceptBackoff)
				continue
			} else {
				// Only log an error if this didn't happen due to a Close.
				if ch.State() >= ChannelStartClose {
					return
				}
				ch.log.WithFields(ErrField(err)).Fatal("Unrecoverable accept error, closing server.")
				return
			}
		}

		acceptBackoff = 0

		// Perform the connection handshake in a background goroutine.
		go func() {
			// Register the connection in the peer once the channel is set up.
			events := connectionEvents{
				OnActive:           ch.inboundConnectionActive,
				OnCloseStateChange: ch.connectionCloseStateChange,
				OnExchangeUpdated:  ch.exchangeUpdated,
			}
			if _, err := ch.inboundHandshake(context.Background(), netConn, events); err != nil {
				netConn.Close()
			}
		}()
	}
}
// serve runs the listener to accept and manage new incoming connections, blocking
// until the channel is closed.