libgo/go/net/tcpsock_plan9.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 (
   8         "io"
   9         "os"
  10         "syscall"
  11         "time"
  12 )
  13
  14 // TCPConn is an implementation of the Conn interface for TCP network
  15 // connections.
  16 type TCPConn struct {
  17         conn
  18 }
  19
  20 func newTCPConn(fd *netFD) *TCPConn {
  21         return &TCPConn{conn{fd}}
  22 }
  23
  24 // ReadFrom implements the io.ReaderFrom ReadFrom method.
  25 func (c *TCPConn) ReadFrom(r io.Reader) (int64, error) {
  26         return genericReadFrom(c, r)
  27 }
  28
  29 // CloseRead shuts down the reading side of the TCP connection.
  30 // Most callers should just use Close.
  31 func (c *TCPConn) CloseRead() error {
  32         if !c.ok() {
  33                 return syscall.EINVAL
  34         }
  35         return c.fd.closeRead()
  36 }
  37
  38 // CloseWrite shuts down the writing side of the TCP connection.
  39 // Most callers should just use Close.
  40 func (c *TCPConn) CloseWrite() error {
  41         if !c.ok() {
  42                 return syscall.EINVAL
  43         }
  44         return c.fd.closeWrite()
  45 }
  46
  47 // SetLinger sets the behavior of Close on a connection which still
  48 // has data waiting to be sent or to be acknowledged.
  49 //
  50 // If sec < 0 (the default), the operating system finishes sending the
  51 // data in the background.
  52 //
  53 // If sec == 0, the operating system discards any unsent or
  54 // unacknowledged data.
  55 //
  56 // If sec > 0, the data is sent in the background as with sec < 0. On
  57 // some operating systems after sec seconds have elapsed any remaining
  58 // unsent data may be discarded.
  59 func (c *TCPConn) SetLinger(sec int) error {
  60         return syscall.EPLAN9
  61 }
  62
  63 // SetKeepAlive sets whether the operating system should send
  64 // keepalive messages on the connection.
  65 func (c *TCPConn) SetKeepAlive(keepalive bool) error {
  66         if !c.ok() {
  67                 return syscall.EPLAN9
  68         }
  69         return setKeepAlive(c.fd, keepalive)
  70 }
  71
  72 // SetKeepAlivePeriod sets period between keep alives.
  73 func (c *TCPConn) SetKeepAlivePeriod(d time.Duration) error {
  74         if !c.ok() {
  75                 return syscall.EPLAN9
  76         }
  77         return setKeepAlivePeriod(c.fd, d)
  78 }
  79
  80 // SetNoDelay controls whether the operating system should delay
  81 // packet transmission in hopes of sending fewer packets (Nagle's
  82 // algorithm).  The default is true (no delay), meaning that data is
  83 // sent as soon as possible after a Write.
  84 func (c *TCPConn) SetNoDelay(noDelay bool) error {
  85         return syscall.EPLAN9
  86 }
  87
  88 // DialTCP connects to the remote address raddr on the network net,
  89 // which must be "tcp", "tcp4", or "tcp6".  If laddr is not nil, it is
  90 // used as the local address for the connection.
  91 func DialTCP(net string, laddr, raddr *TCPAddr) (*TCPConn, error) {
  92         return dialTCP(net, laddr, raddr, noDeadline)
  93 }
  94
  95 func dialTCP(net string, laddr, raddr *TCPAddr, deadline time.Time) (*TCPConn, error) {
  96         if !deadline.IsZero() {
  97                 panic("net.dialTCP: deadline not implemented on Plan 9")
  98         }
  99         switch net {
 100         case "tcp", "tcp4", "tcp6":
 101         default:
 102                 return nil, &OpError{"dial", net, raddr, UnknownNetworkError(net)}
 103         }
 104         if raddr == nil {
 105                 return nil, &OpError{"dial", net, nil, errMissingAddress}
 106         }
 107         fd, err := dialPlan9(net, laddr, raddr)
 108         if err != nil {
 109                 return nil, err
 110         }
 111         return newTCPConn(fd), nil
 112 }
 113
 114 // TCPListener is a TCP network listener.  Clients should typically
 115 // use variables of type Listener instead of assuming TCP.
 116 type TCPListener struct {
 117         fd *netFD
 118 }
 119
 120 // AcceptTCP accepts the next incoming call and returns the new
 121 // connection.
 122 func (l *TCPListener) AcceptTCP() (*TCPConn, error) {
 123         if l == nil || l.fd == nil || l.fd.ctl == nil {
 124                 return nil, syscall.EINVAL
 125         }
 126         fd, err := l.fd.acceptPlan9()
 127         if err != nil {
 128                 return nil, err
 129         }
 130         return newTCPConn(fd), nil
 131 }
 132
 133 // Accept implements the Accept method in the Listener interface; it
 134 // waits for the next call and returns a generic Conn.
 135 func (l *TCPListener) Accept() (Conn, error) {
 136         if l == nil || l.fd == nil || l.fd.ctl == nil {
 137                 return nil, syscall.EINVAL
 138         }
 139         c, err := l.AcceptTCP()
 140         if err != nil {
 141                 return nil, err
 142         }
 143         return c, nil
 144 }
 145
 146 // Close stops listening on the TCP address.
 147 // Already Accepted connections are not closed.
 148 func (l *TCPListener) Close() error {
 149         if l == nil || l.fd == nil || l.fd.ctl == nil {
 150                 return syscall.EINVAL
 151         }
 152         if _, err := l.fd.ctl.WriteString("hangup"); err != nil {
 153                 l.fd.ctl.Close()
 154                 return &OpError{"close", l.fd.ctl.Name(), l.fd.laddr, err}
 155         }
 156         return l.fd.ctl.Close()
 157 }
 158
 159 // Addr returns the listener's network address, a *TCPAddr.
 160 func (l *TCPListener) Addr() Addr { return l.fd.laddr }
 161
 162 // SetDeadline sets the deadline associated with the listener.
 163 // A zero time value disables the deadline.
 164 func (l *TCPListener) SetDeadline(t time.Time) error {
 165         if l == nil || l.fd == nil || l.fd.ctl == nil {
 166                 return syscall.EINVAL
 167         }
 168         return l.fd.setDeadline(t)
 169 }
 170
 171 // File returns a copy of the underlying os.File, set to blocking
 172 // mode.  It is the caller's responsibility to close f when finished.
 173 // Closing l does not affect f, and closing f does not affect l.
 174 //
 175 // The returned os.File's file descriptor is different from the
 176 // connection's.  Attempting to change properties of the original
 177 // using this duplicate may or may not have the desired effect.
 178 func (l *TCPListener) File() (f *os.File, err error) { return l.dup() }
 179
 180 // ListenTCP announces on the TCP address laddr and returns a TCP
 181 // listener.  Net must be "tcp", "tcp4", or "tcp6".  If laddr has a
 182 // port of 0, ListenTCP will choose an available port.  The caller can
 183 // use the Addr method of TCPListener to retrieve the chosen address.
 184 func ListenTCP(net string, laddr *TCPAddr) (*TCPListener, error) {
 185         switch net {
 186         case "tcp", "tcp4", "tcp6":
 187         default:
 188                 return nil, &OpError{"listen", net, laddr, UnknownNetworkError(net)}
 189         }
 190         if laddr == nil {
 191                 laddr = &TCPAddr{}
 192         }
 193         fd, err := listenPlan9(net, laddr)
 194         if err != nil {
 195                 return nil, err
 196         }
 197         return &TCPListener{fd}, nil
 198 }