swap net.Conn for net.TCPConn and embed

uacp/conn.go

@@ -9,7 +9,6 @@ import (
 	"io"
 	"net"
 	"sync/atomic"
-	"time"
 
 	"github.com/gopcua/opcua/debug"
 	"github.com/gopcua/opcua/errors"
@@ -36,19 +35,19 @@ func nextid() uint32 {
 
 func Dial(ctx context.Context, endpoint string) (*Conn, error) {
 	debug.Printf("Connect to %s", endpoint)
-	network, raddr, err := ResolveEndpoint(endpoint)
+	_, raddr, err := ResolveEndpoint(endpoint)
 	if err != nil {
 		return nil, err
 	}
 	var dialer net.Dialer
-	c, err := dialer.DialContext(ctx, network, raddr.String())
+	c, err := dialer.DialContext(ctx, "tcp", raddr.String())
 	if err != nil {
 		return nil, err
 	}
 
 	conn := &Conn{
-		id: nextid(),
-		c:  c,
+		TCPConn: c.(*net.TCPConn),
+		id:      nextid(),
 		ack: &Acknowledge{
 			ReceiveBufSize: DefaultReceiveBufSize,
 			SendBufSize:    DefaultSendBufSize,
@@ -68,7 +67,7 @@ func Dial(ctx context.Context, endpoint string) (*Conn, error) {
 
 // Listener is a OPC UA Connection Protocol network listener.
 type Listener struct {
-	l        net.Listener
+	l        *net.TCPListener
 	ack      *Acknowledge
 	endpoint string
 }
@@ -94,7 +93,7 @@ func Listen(endpoint string, ack *Acknowledge) (*Listener, error) {
 	if err != nil {
 		return nil, err
 	}
-	l, err := net.Listen(network, laddr.String())
+	l, err := net.ListenTCP(network, laddr)
 	if err != nil {
 		return nil, err
 	}
@@ -110,11 +109,11 @@ func Listen(endpoint string, ack *Acknowledge) (*Listener, error) {
 // The first param ctx is to be passed to monitor(), which monitors and handles
 // incoming messages automatically in another goroutine.
 func (l *Listener) Accept(ctx context.Context) (*Conn, error) {
-	c, err := l.l.Accept()
+	c, err := l.l.AcceptTCP()
 	if err != nil {
 		return nil, err
 	}
-	conn := &Conn{nextid(), c, l.ack}
+	conn := &Conn{c, nextid(), l.ack}
 	if err := conn.srvhandshake(l.endpoint); err != nil {
 		c.Close()
 		return nil, err
@@ -138,8 +137,8 @@ func (l *Listener) Endpoint() string {
 }
 
 type Conn struct {
+	*net.TCPConn
 	id  uint32
-	c   net.Conn
 	ack *Acknowledge
 }
 
@@ -165,35 +164,7 @@ func (c *Conn) MaxChunkCount() uint32 {
 
 func (c *Conn) Close() error {
 	debug.Printf("conn %d: close", c.id)
-	return c.c.Close()
-}
-
-func (c *Conn) Read(b []byte) (int, error) {
-	return c.c.Read(b)
-}
-
-func (c *Conn) Write(b []byte) (int, error) {
-	return c.c.Write(b)
-}
-
-func (c *Conn) SetDeadline(t time.Time) error {
-	return c.c.SetDeadline(t)
-}
-
-func (c *Conn) SetReadDeadline(t time.Time) error {
-	return c.c.SetReadDeadline(t)
-}
-
-func (c *Conn) SetWriteDeadline(t time.Time) error {
-	return c.c.SetWriteDeadline(t)
-}
-
-func (c *Conn) LocalAddr() net.Addr {
-	return c.c.LocalAddr()
-}
-
-func (c *Conn) RemoteAddr() net.Addr {
-	return c.c.RemoteAddr()
+	return c.TCPConn.Close()
 }
 
 func (c *Conn) handshake(endpoint string) error {
@@ -290,12 +261,13 @@ func (c *Conn) srvhandshake(endpoint string) error {
 			return errors.Errorf("uacp: invalid endpoint url %s", rhe.EndpointURL)
 		}
 		debug.Printf("conn %d: connecting to %s", c.id, rhe.ServerURI)
-		c.c.Close()
-		c, err := Dial(context.Background(), rhe.ServerURI)
+		c.Close()
+		var dialer net.Dialer
+		c2, err := dialer.DialContext(context.Background(), "tcp", rhe.ServerURI)
 		if err != nil {
 			return err
 		}
-		c.c = c
+		c.TCPConn = c2.(*net.TCPConn)
 		debug.Printf("conn %d: recv %#v", c.id, rhe)
 		return nil
 
@@ -322,7 +294,7 @@ const hdrlen = 8
 func (c *Conn) Receive() ([]byte, error) {
 	b := make([]byte, c.ack.ReceiveBufSize)
 
-	if _, err := io.ReadFull(c.c, b[:hdrlen]); err != nil {
+	if _, err := io.ReadFull(c, b[:hdrlen]); err != nil {
 		// todo(fs): do not wrap this error since it hides io.EOF
 		// todo(fs): use golang.org/x/xerrors
 		return nil, err
@@ -337,7 +309,7 @@ func (c *Conn) Receive() ([]byte, error) {
 		return nil, errors.Errorf("uacp: message too large: %d > %d bytes", h.MessageSize, c.ack.ReceiveBufSize)
 	}
 
-	if _, err := io.ReadFull(c.c, b[hdrlen:h.MessageSize]); err != nil {
+	if _, err := io.ReadFull(c, b[hdrlen:h.MessageSize]); err != nil {
 		// todo(fs): do not wrap this error since it hides io.EOF
 		// todo(fs): use golang.org/x/xerrors
 		return nil, err
@@ -381,7 +353,7 @@ func (c *Conn) Send(typ string, msg interface{}) error {
 	}
 
 	b := append(hdr, body...)
-	if _, err := c.c.Write(b); err != nil {
+	if _, err := c.Write(b); err != nil {
 		return errors.Errorf("write failed: %s", err)
 	}
 	debug.Printf("conn %d: sent %s with %d bytes", c.id, typ, len(b))