internal/nettest: add TestableNetwork, NewLocalListener and NewLocalPacketListener
Change-Id: I61475922625ce8dbeee4180807c3f021a502edf7
Reviewed-on: https://go-review.googlesource.com/34731
Run-TryBot: Mikio Hara <mikioh.mikioh@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
diff --git a/internal/nettest/stack.go b/internal/nettest/stack.go
index 5ab9530..2808b57 100644
--- a/internal/nettest/stack.go
+++ b/internal/nettest/stack.go
@@ -5,32 +5,37 @@
// Package nettest provides utilities for IP testing.
package nettest // import "golang.org/x/net/internal/nettest"
-import "net"
+import (
+ "fmt"
+ "io/ioutil"
+ "net"
+ "os"
+ "runtime"
+)
+
+var (
+ supportsIPv4 bool
+ supportsIPv6 bool
+)
+
+func init() {
+ if ln, err := net.Listen("tcp4", "127.0.0.1:0"); err == nil {
+ ln.Close()
+ supportsIPv4 = true
+ }
+ if ln, err := net.Listen("tcp6", "[::1]:0"); err == nil {
+ ln.Close()
+ supportsIPv6 = true
+ }
+}
// SupportsIPv4 reports whether the platform supports IPv4 networking
// functionality.
-func SupportsIPv4() bool {
- ln, err := net.Listen("tcp4", "127.0.0.1:0")
- if err != nil {
- return false
- }
- ln.Close()
- return true
-}
+func SupportsIPv4() bool { return supportsIPv4 }
// SupportsIPv6 reports whether the platform supports IPv6 networking
// functionality.
-func SupportsIPv6() bool {
- if causesIPv6Crash() {
- return false
- }
- ln, err := net.Listen("tcp6", "[::1]:0")
- if err != nil {
- return false
- }
- ln.Close()
- return true
-}
+func SupportsIPv6() bool { return supportsIPv6 }
// SupportsRawIPSocket reports whether the platform supports raw IP
// sockets.
@@ -50,3 +55,93 @@
func ProtocolNotSupported(err error) bool {
return protocolNotSupported(err)
}
+
+// TestableNetwork reports whether network is testable on the current
+// platform configuration.
+func TestableNetwork(network string) bool {
+ // This is based on logic from standard library's
+ // net/platform_test.go.
+ switch network {
+ case "unix":
+ switch runtime.GOOS {
+ case "android", "nacl", "plan9", "windows":
+ return false
+ }
+ if runtime.GOOS == "darwin" && (runtime.GOARCH == "arm" || runtime.GOARCH == "arm64") {
+ return false
+ }
+ case "unixpacket":
+ switch runtime.GOOS {
+ case "android", "darwin", "freebsd", "nacl", "plan9", "windows":
+ return false
+ }
+ }
+ return true
+}
+
+// NewLocalListener returns a listener which listens to a loopback IP
+// address or local file system path.
+// Network must be "tcp", "tcp4", "tcp6", "unix" or "unixpacket".
+func NewLocalListener(network string) (net.Listener, error) {
+ switch network {
+ case "tcp":
+ if supportsIPv4 {
+ if ln, err := net.Listen("tcp4", "127.0.0.1:0"); err == nil {
+ return ln, nil
+ }
+ }
+ if supportsIPv6 {
+ return net.Listen("tcp6", "[::1]:0")
+ }
+ case "tcp4":
+ if supportsIPv4 {
+ return net.Listen("tcp4", "127.0.0.1:0")
+ }
+ case "tcp6":
+ if supportsIPv6 {
+ return net.Listen("tcp6", "[::1]:0")
+ }
+ case "unix", "unixpacket":
+ return net.Listen(network, localPath())
+ }
+ return nil, fmt.Errorf("%s is not supported", network)
+}
+
+// NewLocalPacketListener returns a packet listener which listens to a
+// loopback IP address or local file system path.
+// Network must be "udp", "udp4", "udp6" or "unixgram".
+func NewLocalPacketListener(network string) (net.PacketConn, error) {
+ switch network {
+ case "udp":
+ if supportsIPv4 {
+ if c, err := net.ListenPacket("udp4", "127.0.0.1:0"); err == nil {
+ return c, nil
+ }
+ }
+ if supportsIPv6 {
+ return net.ListenPacket("udp6", "[::1]:0")
+ }
+ case "udp4":
+ if supportsIPv4 {
+ return net.ListenPacket("udp4", "127.0.0.1:0")
+ }
+ case "udp6":
+ if supportsIPv6 {
+ return net.ListenPacket("udp6", "[::1]:0")
+ }
+ case "unixgram":
+ return net.ListenPacket(network, localPath())
+ }
+ return nil, fmt.Errorf("%s is not supported", network)
+}
+
+func localPath() string {
+ f, err := ioutil.TempFile("", "nettest")
+ if err != nil {
+ panic(err)
+ }
+ path := f.Name()
+ f.Close()
+ os.Remove(path)
+ return path
+}
