libgo/go/net/udpsock.go

   1 // Copyright 2009 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 "errors"
   8
   9 var ErrWriteToConnected = errors.New("use of WriteTo with pre-connected UDP")
  10
  11 // UDPAddr represents the address of a UDP end point.
  12 type UDPAddr struct {
  13         IP   IP
  14         Port int
  15         Zone string // IPv6 scoped addressing zone
  16 }
  17
  18 // Network returns the address's network name, "udp".
  19 func (a *UDPAddr) Network() string { return "udp" }
  20
  21 func (a *UDPAddr) String() string {
  22         if a == nil {
  23                 return "<nil>"
  24         }
  25         ip := ipEmptyString(a.IP)
  26         if a.Zone != "" {
  27                 return JoinHostPort(ip+"%"+a.Zone, itoa(a.Port))
  28         }
  29         return JoinHostPort(ip, itoa(a.Port))
  30 }
  31
  32 func (a *UDPAddr) toAddr() Addr {
  33         if a == nil {
  34                 return nil
  35         }
  36         return a
  37 }
  38
  39 // ResolveUDPAddr parses addr as a UDP address of the form "host:port"
  40 // or "[ipv6-host%zone]:port" and resolves a pair of domain name and
  41 // port name on the network net, which must be "udp", "udp4" or
  42 // "udp6".  A literal address or host name for IPv6 must be enclosed
  43 // in square brackets, as in "[::1]:80", "[ipv6-host]:http" or
  44 // "[ipv6-host%zone]:80".
  45 func ResolveUDPAddr(net, addr string) (*UDPAddr, error) {
  46         switch net {
  47         case "udp", "udp4", "udp6":
  48         case "": // a hint wildcard for Go 1.0 undocumented behavior
  49                 net = "udp"
  50         default:
  51                 return nil, UnknownNetworkError(net)
  52         }
  53         a, err := resolveInternetAddr(net, addr, noDeadline)
  54         if err != nil {
  55                 return nil, err
  56         }
  57         return a.toAddr().(*UDPAddr), nil
  58 }