diff options
Diffstat (limited to 'libgo/go/net/udpsock_posix.go')
-rw-r--r-- | libgo/go/net/udpsock_posix.go | 294 |
1 files changed, 294 insertions, 0 deletions
diff --git a/libgo/go/net/udpsock_posix.go b/libgo/go/net/udpsock_posix.go new file mode 100644 index 0000000..d4ea056 --- /dev/null +++ b/libgo/go/net/udpsock_posix.go @@ -0,0 +1,294 @@ +// Copyright 2009 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +// UDP sockets + +package net + +import ( + "os" + "syscall" +) + +func sockaddrToUDP(sa syscall.Sockaddr) Addr { + switch sa := sa.(type) { + case *syscall.SockaddrInet4: + return &UDPAddr{sa.Addr[0:], sa.Port} + case *syscall.SockaddrInet6: + return &UDPAddr{sa.Addr[0:], sa.Port} + } + return nil +} + +func (a *UDPAddr) family() int { + if a == nil || len(a.IP) <= 4 { + return syscall.AF_INET + } + if a.IP.To4() != nil { + return syscall.AF_INET + } + return syscall.AF_INET6 +} + +func (a *UDPAddr) sockaddr(family int) (syscall.Sockaddr, os.Error) { + return ipToSockaddr(family, a.IP, a.Port) +} + +func (a *UDPAddr) toAddr() sockaddr { + if a == nil { // nil *UDPAddr + return nil // nil interface + } + return a +} + +// UDPConn is the implementation of the Conn and PacketConn +// interfaces for UDP network connections. +type UDPConn struct { + fd *netFD +} + +func newUDPConn(fd *netFD) *UDPConn { return &UDPConn{fd} } + +func (c *UDPConn) ok() bool { return c != nil && c.fd != nil } + +// Implementation of the Conn interface - see Conn for documentation. + +// Read implements the net.Conn Read method. +func (c *UDPConn) Read(b []byte) (n int, err os.Error) { + if !c.ok() { + return 0, os.EINVAL + } + return c.fd.Read(b) +} + +// Write implements the net.Conn Write method. +func (c *UDPConn) Write(b []byte) (n int, err os.Error) { + if !c.ok() { + return 0, os.EINVAL + } + return c.fd.Write(b) +} + +// Close closes the UDP connection. +func (c *UDPConn) Close() os.Error { + if !c.ok() { + return os.EINVAL + } + err := c.fd.Close() + c.fd = nil + return err +} + +// LocalAddr returns the local network address. +func (c *UDPConn) LocalAddr() Addr { + if !c.ok() { + return nil + } + return c.fd.laddr +} + +// RemoteAddr returns the remote network address, a *UDPAddr. +func (c *UDPConn) RemoteAddr() Addr { + if !c.ok() { + return nil + } + return c.fd.raddr +} + +// SetTimeout implements the net.Conn SetTimeout method. +func (c *UDPConn) SetTimeout(nsec int64) os.Error { + if !c.ok() { + return os.EINVAL + } + return setTimeout(c.fd, nsec) +} + +// SetReadTimeout implements the net.Conn SetReadTimeout method. +func (c *UDPConn) SetReadTimeout(nsec int64) os.Error { + if !c.ok() { + return os.EINVAL + } + return setReadTimeout(c.fd, nsec) +} + +// SetWriteTimeout implements the net.Conn SetWriteTimeout method. +func (c *UDPConn) SetWriteTimeout(nsec int64) os.Error { + if !c.ok() { + return os.EINVAL + } + return setWriteTimeout(c.fd, nsec) +} + +// SetReadBuffer sets the size of the operating system's +// receive buffer associated with the connection. +func (c *UDPConn) SetReadBuffer(bytes int) os.Error { + if !c.ok() { + return os.EINVAL + } + return setReadBuffer(c.fd, bytes) +} + +// SetWriteBuffer sets the size of the operating system's +// transmit buffer associated with the connection. +func (c *UDPConn) SetWriteBuffer(bytes int) os.Error { + if !c.ok() { + return os.EINVAL + } + return setWriteBuffer(c.fd, bytes) +} + +// UDP-specific methods. + +// ReadFromUDP reads a UDP packet from c, copying the payload into b. +// It returns the number of bytes copied into b and the return address +// that was on the packet. +// +// ReadFromUDP can be made to time out and return an error with Timeout() == true +// after a fixed time limit; see SetTimeout and SetReadTimeout. +func (c *UDPConn) ReadFromUDP(b []byte) (n int, addr *UDPAddr, err os.Error) { + if !c.ok() { + return 0, nil, os.EINVAL + } + n, sa, err := c.fd.ReadFrom(b) + switch sa := sa.(type) { + case *syscall.SockaddrInet4: + addr = &UDPAddr{sa.Addr[0:], sa.Port} + case *syscall.SockaddrInet6: + addr = &UDPAddr{sa.Addr[0:], sa.Port} + } + return +} + +// ReadFrom implements the net.PacketConn ReadFrom method. +func (c *UDPConn) ReadFrom(b []byte) (n int, addr Addr, err os.Error) { + if !c.ok() { + return 0, nil, os.EINVAL + } + n, uaddr, err := c.ReadFromUDP(b) + return n, uaddr.toAddr(), err +} + +// WriteToUDP writes a UDP packet to addr via c, copying the payload from b. +// +// WriteToUDP can be made to time out and return +// an error with Timeout() == true after a fixed time limit; +// see SetTimeout and SetWriteTimeout. +// On packet-oriented connections, write timeouts are rare. +func (c *UDPConn) WriteToUDP(b []byte, addr *UDPAddr) (n int, err os.Error) { + if !c.ok() { + return 0, os.EINVAL + } + sa, err1 := addr.sockaddr(c.fd.family) + if err1 != nil { + return 0, &OpError{Op: "write", Net: "udp", Addr: addr, Error: err1} + } + return c.fd.WriteTo(b, sa) +} + +// WriteTo implements the net.PacketConn WriteTo method. +func (c *UDPConn) WriteTo(b []byte, addr Addr) (n int, err os.Error) { + if !c.ok() { + return 0, os.EINVAL + } + a, ok := addr.(*UDPAddr) + if !ok { + return 0, &OpError{"writeto", "udp", addr, os.EINVAL} + } + return c.WriteToUDP(b, a) +} + +// DialUDP connects to the remote address raddr on the network net, +// which must be "udp", "udp4", or "udp6". If laddr is not nil, it is used +// as the local address for the connection. +func DialUDP(net string, laddr, raddr *UDPAddr) (c *UDPConn, err os.Error) { + switch net { + case "udp", "udp4", "udp6": + default: + return nil, UnknownNetworkError(net) + } + if raddr == nil { + return nil, &OpError{"dial", "udp", nil, errMissingAddress} + } + fd, e := internetSocket(net, laddr.toAddr(), raddr.toAddr(), syscall.SOCK_DGRAM, 0, "dial", sockaddrToUDP) + if e != nil { + return nil, e + } + return newUDPConn(fd), nil +} + +// ListenUDP listens for incoming UDP packets addressed to the +// local address laddr. The returned connection c's ReadFrom +// and WriteTo methods can be used to receive and send UDP +// packets with per-packet addressing. +func ListenUDP(net string, laddr *UDPAddr) (c *UDPConn, err os.Error) { + switch net { + case "udp", "udp4", "udp6": + default: + return nil, UnknownNetworkError(net) + } + if laddr == nil { + return nil, &OpError{"listen", "udp", nil, errMissingAddress} + } + fd, e := internetSocket(net, laddr.toAddr(), nil, syscall.SOCK_DGRAM, 0, "dial", sockaddrToUDP) + if e != nil { + return nil, e + } + return newUDPConn(fd), nil +} + +// BindToDevice binds a UDPConn to a network interface. +func (c *UDPConn) BindToDevice(device string) os.Error { + if !c.ok() { + return os.EINVAL + } + c.fd.incref() + defer c.fd.decref() + return os.NewSyscallError("setsockopt", syscall.BindToDevice(c.fd.sysfd, device)) +} + +// File returns a copy of the underlying os.File, set to blocking mode. +// It is the caller's responsibility to close f when finished. +// Closing c does not affect f, and closing f does not affect c. +func (c *UDPConn) File() (f *os.File, err os.Error) { return c.fd.dup() } + +var errInvalidMulticast = os.NewError("invalid IPv4 multicast address") + +// JoinGroup joins the IPv4 multicast group named by addr. +// The UDPConn must use the "udp4" network. +func (c *UDPConn) JoinGroup(addr IP) os.Error { + if !c.ok() { + return os.EINVAL + } + ip := addr.To4() + if ip == nil { + return &OpError{"joingroup", "udp", &IPAddr{ip}, errInvalidMulticast} + } + mreq := &syscall.IPMreq{ + Multiaddr: [4]byte{ip[0], ip[1], ip[2], ip[3]}, + } + err := os.NewSyscallError("setsockopt", syscall.SetsockoptIPMreq(c.fd.sysfd, syscall.IPPROTO_IP, syscall.IP_ADD_MEMBERSHIP, mreq)) + if err != nil { + return &OpError{"joingroup", "udp", &IPAddr{ip}, err} + } + return nil +} + +// LeaveGroup exits the IPv4 multicast group named by addr. +func (c *UDPConn) LeaveGroup(addr IP) os.Error { + if !c.ok() { + return os.EINVAL + } + ip := addr.To4() + if ip == nil { + return &OpError{"leavegroup", "udp", &IPAddr{ip}, errInvalidMulticast} + } + mreq := &syscall.IPMreq{ + Multiaddr: [4]byte{ip[0], ip[1], ip[2], ip[3]}, + } + err := os.NewSyscallError("setsockopt", syscall.SetsockoptIPMreq(c.fd.sysfd, syscall.IPPROTO_IP, syscall.IP_DROP_MEMBERSHIP, mreq)) + if err != nil { + return &OpError{"leavegroup", "udp", &IPAddr{ip}, err} + } + return nil +} |