1 files changed, 38 insertions, 31 deletions

diff --git a/libgo/go/net/mockserver_test.go b/libgo/go/net/mockserver_test.go
index dd6f4df3b9..766de6a815 100644
--- a/libgo/go/net/mockserver_test.go
+++ b/libgo/go/net/mockserver_test.go
@@ -30,10 +30,20 @@ func testUnixAddr() string {
 
 func newLocalListener(network string) (Listener, error) {
 	switch network {
-	case "tcp", "tcp4", "tcp6":
+	case "tcp":
+		if supportsIPv4 {
+			if ln, err := Listen("tcp4", "127.0.0.1:0"); err == nil {
+				return ln, nil
+			}
+		}
+		if supportsIPv6 {
+			return Listen("tcp6", "[::1]:0")
+		}
+	case "tcp4":
 		if supportsIPv4 {
 			return Listen("tcp4", "127.0.0.1:0")
 		}
+	case "tcp6":
 		if supportsIPv6 {
 			return Listen("tcp6", "[::1]:0")
 		}
@@ -142,13 +152,6 @@ func (dss *dualStackServer) buildup(handler func(*dualStackServer, Listener)) er
 	return nil
 }
 
-func (dss *dualStackServer) putConn(c Conn) error {
-	dss.cmu.Lock()
-	dss.cs = append(dss.cs, c)
-	dss.cmu.Unlock()
-	return nil
-}
-
 func (dss *dualStackServer) teardownNetwork(network string) error {
 	dss.lnmu.Lock()
 	for i := range dss.lns {
@@ -181,28 +184,24 @@ func (dss *dualStackServer) teardown() error {
 	return nil
 }
 
-func newDualStackServer(lns []streamListener) (*dualStackServer, error) {
-	dss := &dualStackServer{lns: lns, port: "0"}
-	for i := range dss.lns {
-		ln, err := Listen(dss.lns[i].network, JoinHostPort(dss.lns[i].address, dss.port))
-		if err != nil {
-			for _, ln := range dss.lns[:i] {
-				ln.Listener.Close()
-			}
-			return nil, err
-		}
-		dss.lns[i].Listener = ln
-		dss.lns[i].done = make(chan bool)
-		if dss.port == "0" {
-			if _, dss.port, err = SplitHostPort(ln.Addr().String()); err != nil {
-				for _, ln := range dss.lns {
-					ln.Listener.Close()
-				}
-				return nil, err
-			}
-		}
+func newDualStackServer() (*dualStackServer, error) {
+	lns, err := newDualStackListener()
+	if err != nil {
+		return nil, err
+	}
+	_, port, err := SplitHostPort(lns[0].Addr().String())
+	if err != nil {
+		lns[0].Close()
+		lns[1].Close()
+		return nil, err
 	}
-	return dss, nil
+	return &dualStackServer{
+		lns: []streamListener{
+			{network: "tcp4", address: lns[0].Addr().String(), Listener: lns[0], done: make(chan bool)},
+			{network: "tcp6", address: lns[1].Addr().String(), Listener: lns[1], done: make(chan bool)},
+		},
+		port: port,
+	}, nil
 }
 
 func transponder(ln Listener, ch chan<- error) {
@@ -225,7 +224,7 @@ func transponder(ln Listener, ch chan<- error) {
 	defer c.Close()
 
 	network := ln.Addr().Network()
-	if c.LocalAddr().Network() != network || c.LocalAddr().Network() != network {
+	if c.LocalAddr().Network() != network || c.RemoteAddr().Network() != network {
 		ch <- fmt.Errorf("got %v->%v; expected %v->%v", c.LocalAddr().Network(), c.RemoteAddr().Network(), network, network)
 		return
 	}
@@ -333,10 +332,18 @@ func timeoutTransmitter(c Conn, d, min, max time.Duration, ch chan<- error) {
 
 func newLocalPacketListener(network string) (PacketConn, error) {
 	switch network {
-	case "udp", "udp4", "udp6":
+	case "udp":
+		if supportsIPv4 {
+			return ListenPacket("udp4", "127.0.0.1:0")
+		}
+		if supportsIPv6 {
+			return ListenPacket("udp6", "[::1]:0")
+		}
+	case "udp4":
 		if supportsIPv4 {
 			return ListenPacket("udp4", "127.0.0.1:0")
 		}
+	case "udp6":
 		if supportsIPv6 {
 			return ListenPacket("udp6", "[::1]:0")
 		}