libgo/go/net/dial.go

   1 // Copyright 2010 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 "os"
   8
   9 // Dial connects to the remote address raddr on the network net.
  10 // If the string laddr is not empty, it is used as the local address
  11 // for the connection.
  12 //
  13 // Known networks are "tcp", "tcp4" (IPv4-only), "tcp6" (IPv6-only),
  14 // "udp", "udp4" (IPv4-only), "udp6" (IPv6-only), "ip", "ip4"
  15 // (IPv4-only), "ip6" (IPv6-only), "unix" and "unixgram".
  16 //
  17 // For IP networks, addresses have the form host:port.  If host is
  18 // a literal IPv6 address, it must be enclosed in square brackets.
  19 //
  20 // Examples:
  21 //      Dial("tcp", "", "12.34.56.78:80")
  22 //      Dial("tcp", "", "google.com:80")
  23 //      Dial("tcp", "", "[de:ad:be:ef::ca:fe]:80")
  24 //      Dial("tcp", "127.0.0.1:123", "127.0.0.1:88")
  25 //
  26 func Dial(net, laddr, raddr string) (c Conn, err os.Error) {
  27         switch prefixBefore(net, ':') {
  28         case "tcp", "tcp4", "tcp6":
  29                 var la, ra *TCPAddr
  30                 if laddr != "" {
  31                         if la, err = ResolveTCPAddr(laddr); err != nil {
  32                                 goto Error
  33                         }
  34                 }
  35                 if raddr != "" {
  36                         if ra, err = ResolveTCPAddr(raddr); err != nil {
  37                                 goto Error
  38                         }
  39                 }
  40                 c, err := DialTCP(net, la, ra)
  41                 if err != nil {
  42                         return nil, err
  43                 }
  44                 return c, nil
  45         case "udp", "udp4", "udp6":
  46                 var la, ra *UDPAddr
  47                 if laddr != "" {
  48                         if la, err = ResolveUDPAddr(laddr); err != nil {
  49                                 goto Error
  50                         }
  51                 }
  52                 if raddr != "" {
  53                         if ra, err = ResolveUDPAddr(raddr); err != nil {
  54                                 goto Error
  55                         }
  56                 }
  57                 c, err := DialUDP(net, la, ra)
  58                 if err != nil {
  59                         return nil, err
  60                 }
  61                 return c, nil
  62         case "unix", "unixgram", "unixpacket":
  63                 var la, ra *UnixAddr
  64                 if raddr != "" {
  65                         if ra, err = ResolveUnixAddr(net, raddr); err != nil {
  66                                 goto Error
  67                         }
  68                 }
  69                 if laddr != "" {
  70                         if la, err = ResolveUnixAddr(net, laddr); err != nil {
  71                                 goto Error
  72                         }
  73                 }
  74                 c, err = DialUnix(net, la, ra)
  75                 if err != nil {
  76                         return nil, err
  77                 }
  78                 return c, nil
  79         case "ip", "ip4", "ip6":
  80                 var la, ra *IPAddr
  81                 if laddr != "" {
  82                         if la, err = ResolveIPAddr(laddr); err != nil {
  83                                 goto Error
  84                         }
  85                 }
  86                 if raddr != "" {
  87                         if ra, err = ResolveIPAddr(raddr); err != nil {
  88                                 goto Error
  89                         }
  90                 }
  91                 c, err := DialIP(net, la, ra)
  92                 if err != nil {
  93                         return nil, err
  94                 }
  95                 return c, nil
  96
  97         }
  98         err = UnknownNetworkError(net)
  99 Error:
 100         return nil, &OpError{"dial", net + " " + raddr, nil, err}
 101 }
 102
 103 // Listen announces on the local network address laddr.
 104 // The network string net must be a stream-oriented
 105 // network: "tcp", "tcp4", "tcp6", or "unix", or "unixpacket".
 106 func Listen(net, laddr string) (l Listener, err os.Error) {
 107         switch net {
 108         case "tcp", "tcp4", "tcp6":
 109                 var la *TCPAddr
 110                 if laddr != "" {
 111                         if la, err = ResolveTCPAddr(laddr); err != nil {
 112                                 return nil, err
 113                         }
 114                 }
 115                 l, err := ListenTCP(net, la)
 116                 if err != nil {
 117                         return nil, err
 118                 }
 119                 return l, nil
 120         case "unix", "unixpacket":
 121                 var la *UnixAddr
 122                 if laddr != "" {
 123                         if la, err = ResolveUnixAddr(net, laddr); err != nil {
 124                                 return nil, err
 125                         }
 126                 }
 127                 l, err := ListenUnix(net, la)
 128                 if err != nil {
 129                         return nil, err
 130                 }
 131                 return l, nil
 132         }
 133         return nil, UnknownNetworkError(net)
 134 }
 135
 136 // ListenPacket announces on the local network address laddr.
 137 // The network string net must be a packet-oriented network:
 138 // "udp", "udp4", "udp6", or "unixgram".
 139 func ListenPacket(net, laddr string) (c PacketConn, err os.Error) {
 140         switch prefixBefore(net, ':') {
 141         case "udp", "udp4", "udp6":
 142                 var la *UDPAddr
 143                 if laddr != "" {
 144                         if la, err = ResolveUDPAddr(laddr); err != nil {
 145                                 return nil, err
 146                         }
 147                 }
 148                 c, err := ListenUDP(net, la)
 149                 if err != nil {
 150                         return nil, err
 151                 }
 152                 return c, nil
 153         case "unixgram":
 154                 var la *UnixAddr
 155                 if laddr != "" {
 156                         if la, err = ResolveUnixAddr(net, laddr); err != nil {
 157                                 return nil, err
 158                         }
 159                 }
 160                 c, err := DialUnix(net, la, nil)
 161                 if err != nil {
 162                         return nil, err
 163                 }
 164                 return c, nil
 165         case "ip", "ip4", "ip6":
 166                 var la *IPAddr
 167                 if laddr != "" {
 168                         if la, err = ResolveIPAddr(laddr); err != nil {
 169                                 return nil, err
 170                         }
 171                 }
 172                 c, err := ListenIP(net, la)
 173                 if err != nil {
 174                         return nil, err
 175                 }
 176                 return c, nil
 177         }
 178         return nil, UnknownNetworkError(net)
 179 }