libgo/go/net/udpsock_plan9_test.go

   1 // Copyright 2016 The Go Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style
   3 // license that can be found in the LICENSE file.
   4
   5 package net
   6
   7 import (
   8         "internal/testenv"
   9         "runtime"
  10         "testing"
  11 )
  12
  13 func TestListenMulticastUDP(t *testing.T) {
  14         testenv.MustHaveExternalNetwork(t)
  15
  16         ifcs, err := Interfaces()
  17         if err != nil {
  18                 t.Skip(err.Error())
  19         }
  20         if len(ifcs) == 0 {
  21                 t.Skip("no network interfaces found")
  22         }
  23
  24         var mifc *Interface
  25         for _, ifc := range ifcs {
  26                 if ifc.Flags&FlagUp|FlagMulticast != FlagUp|FlagMulticast {
  27                         continue
  28                 }
  29                 mifc = &ifc
  30                 break
  31         }
  32
  33         if mifc == nil {
  34                 t.Skipf("no multicast interfaces found")
  35         }
  36
  37         c1, err := ListenMulticastUDP("udp4", mifc, &UDPAddr{IP: ParseIP("224.0.0.254")})
  38         if err != nil {
  39                 t.Fatalf("multicast not working on %s", runtime.GOOS)
  40         }
  41         c1addr := c1.LocalAddr().(*UDPAddr)
  42         if err != nil {
  43                 t.Fatal(err)
  44         }
  45         defer c1.Close()
  46
  47         c2, err := ListenUDP("udp4", &UDPAddr{IP: IPv4zero, Port: 0})
  48         c2addr := c2.LocalAddr().(*UDPAddr)
  49         if err != nil {
  50                 t.Fatal(err)
  51         }
  52         defer c2.Close()
  53
  54         n, err := c2.WriteToUDP([]byte("data"), c1addr)
  55         if err != nil {
  56                 t.Fatal(err)
  57         }
  58         if n != 4 {
  59                 t.Fatalf("got %d; want 4", n)
  60         }
  61
  62         n, err = c1.WriteToUDP([]byte("data"), c2addr)
  63         if err != nil {
  64                 t.Fatal(err)
  65         }
  66         if n != 4 {
  67                 t.Fatalf("got %d; want 4", n)
  68         }
  69 }