diff options
author | Tianon Gravi <admwiggin@gmail.com> | 2015-01-15 11:54:00 -0700 |
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committer | Tianon Gravi <admwiggin@gmail.com> | 2015-01-15 11:54:00 -0700 |
commit | f154da9e12608589e8d5f0508f908a0c3e88a1bb (patch) | |
tree | f8255d51e10c6f1e0ed69702200b966c9556a431 /src/net/udpsock_posix.go | |
parent | 8d8329ed5dfb9622c82a9fbec6fd99a580f9c9f6 (diff) | |
download | golang-upstream/1.4.tar.gz |
Imported Upstream version 1.4upstream/1.4
Diffstat (limited to 'src/net/udpsock_posix.go')
-rw-r--r-- | src/net/udpsock_posix.go | 268 |
1 files changed, 268 insertions, 0 deletions
diff --git a/src/net/udpsock_posix.go b/src/net/udpsock_posix.go new file mode 100644 index 000000000..a0533366a --- /dev/null +++ b/src/net/udpsock_posix.go @@ -0,0 +1,268 @@ +// 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. + +// +build darwin dragonfly freebsd linux nacl netbsd openbsd solaris windows + +package net + +import ( + "syscall" + "time" +) + +func sockaddrToUDP(sa syscall.Sockaddr) Addr { + switch sa := sa.(type) { + case *syscall.SockaddrInet4: + return &UDPAddr{IP: sa.Addr[0:], Port: sa.Port} + case *syscall.SockaddrInet6: + return &UDPAddr{IP: sa.Addr[0:], Port: sa.Port, Zone: zoneToString(int(sa.ZoneId))} + } + return nil +} + +func (a *UDPAddr) family() int { + if a == nil || len(a.IP) <= IPv4len { + return syscall.AF_INET + } + if a.IP.To4() != nil { + return syscall.AF_INET + } + return syscall.AF_INET6 +} + +func (a *UDPAddr) isWildcard() bool { + if a == nil || a.IP == nil { + return true + } + return a.IP.IsUnspecified() +} + +func (a *UDPAddr) sockaddr(family int) (syscall.Sockaddr, error) { + if a == nil { + return nil, nil + } + return ipToSockaddr(family, a.IP, a.Port, a.Zone) +} + +// UDPConn is the implementation of the Conn and PacketConn interfaces +// for UDP network connections. +type UDPConn struct { + conn +} + +func newUDPConn(fd *netFD) *UDPConn { return &UDPConn{conn{fd}} } + +// 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 SetDeadline and +// SetReadDeadline. +func (c *UDPConn) ReadFromUDP(b []byte) (n int, addr *UDPAddr, err error) { + if !c.ok() { + return 0, nil, syscall.EINVAL + } + n, sa, err := c.fd.readFrom(b) + switch sa := sa.(type) { + case *syscall.SockaddrInet4: + addr = &UDPAddr{IP: sa.Addr[0:], Port: sa.Port} + case *syscall.SockaddrInet6: + addr = &UDPAddr{IP: sa.Addr[0:], Port: sa.Port, Zone: zoneToString(int(sa.ZoneId))} + } + return +} + +// ReadFrom implements the PacketConn ReadFrom method. +func (c *UDPConn) ReadFrom(b []byte) (int, Addr, error) { + if !c.ok() { + return 0, nil, syscall.EINVAL + } + n, addr, err := c.ReadFromUDP(b) + return n, addr.toAddr(), err +} + +// ReadMsgUDP reads a packet from c, copying the payload into b and +// the associated out-of-band data into oob. It returns the number +// of bytes copied into b, the number of bytes copied into oob, the +// flags that were set on the packet and the source address of the +// packet. +func (c *UDPConn) ReadMsgUDP(b, oob []byte) (n, oobn, flags int, addr *UDPAddr, err error) { + if !c.ok() { + return 0, 0, 0, nil, syscall.EINVAL + } + var sa syscall.Sockaddr + n, oobn, flags, sa, err = c.fd.readMsg(b, oob) + switch sa := sa.(type) { + case *syscall.SockaddrInet4: + addr = &UDPAddr{IP: sa.Addr[0:], Port: sa.Port} + case *syscall.SockaddrInet6: + addr = &UDPAddr{IP: sa.Addr[0:], Port: sa.Port, Zone: zoneToString(int(sa.ZoneId))} + } + return +} + +// 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 SetDeadline and +// SetWriteDeadline. On packet-oriented connections, write timeouts +// are rare. +func (c *UDPConn) WriteToUDP(b []byte, addr *UDPAddr) (int, error) { + if !c.ok() { + return 0, syscall.EINVAL + } + if c.fd.isConnected { + return 0, &OpError{"write", c.fd.net, addr, ErrWriteToConnected} + } + if addr == nil { + return 0, &OpError{Op: "write", Net: c.fd.net, Addr: nil, Err: errMissingAddress} + } + sa, err := addr.sockaddr(c.fd.family) + if err != nil { + return 0, &OpError{"write", c.fd.net, addr, err} + } + return c.fd.writeTo(b, sa) +} + +// WriteTo implements the PacketConn WriteTo method. +func (c *UDPConn) WriteTo(b []byte, addr Addr) (int, error) { + if !c.ok() { + return 0, syscall.EINVAL + } + a, ok := addr.(*UDPAddr) + if !ok { + return 0, &OpError{"write", c.fd.net, addr, syscall.EINVAL} + } + return c.WriteToUDP(b, a) +} + +// WriteMsgUDP writes a packet to addr via c, copying the payload from +// b and the associated out-of-band data from oob. It returns the +// number of payload and out-of-band bytes written. +func (c *UDPConn) WriteMsgUDP(b, oob []byte, addr *UDPAddr) (n, oobn int, err error) { + if !c.ok() { + return 0, 0, syscall.EINVAL + } + if c.fd.isConnected { + return 0, 0, &OpError{"write", c.fd.net, addr, ErrWriteToConnected} + } + if addr == nil { + return 0, 0, &OpError{Op: "write", Net: c.fd.net, Addr: nil, Err: errMissingAddress} + } + sa, err := addr.sockaddr(c.fd.family) + if err != nil { + return 0, 0, &OpError{"write", c.fd.net, addr, err} + } + return c.fd.writeMsg(b, oob, sa) +} + +// 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) (*UDPConn, error) { + switch net { + case "udp", "udp4", "udp6": + default: + return nil, &OpError{Op: "dial", Net: net, Addr: raddr, Err: UnknownNetworkError(net)} + } + if raddr == nil { + return nil, &OpError{Op: "dial", Net: net, Addr: nil, Err: errMissingAddress} + } + return dialUDP(net, laddr, raddr, noDeadline) +} + +func dialUDP(net string, laddr, raddr *UDPAddr, deadline time.Time) (*UDPConn, error) { + fd, err := internetSocket(net, laddr, raddr, deadline, syscall.SOCK_DGRAM, 0, "dial") + if err != nil { + return nil, &OpError{Op: "dial", Net: net, Addr: raddr, Err: err} + } + return newUDPConn(fd), nil +} + +// ListenUDP listens for incoming UDP packets addressed to the local +// address laddr. Net must be "udp", "udp4", or "udp6". If laddr has +// a port of 0, ListenUDP will choose an available port. +// The LocalAddr method of the returned UDPConn can be used to +// discover the port. The returned connection's ReadFrom and WriteTo +// methods can be used to receive and send UDP packets with per-packet +// addressing. +func ListenUDP(net string, laddr *UDPAddr) (*UDPConn, error) { + switch net { + case "udp", "udp4", "udp6": + default: + return nil, &OpError{Op: "listen", Net: net, Addr: laddr, Err: UnknownNetworkError(net)} + } + if laddr == nil { + laddr = &UDPAddr{} + } + fd, err := internetSocket(net, laddr, nil, noDeadline, syscall.SOCK_DGRAM, 0, "listen") + if err != nil { + return nil, &OpError{Op: "listen", Net: net, Addr: laddr, Err: err} + } + return newUDPConn(fd), nil +} + +// ListenMulticastUDP listens for incoming multicast UDP packets +// addressed to the group address gaddr on ifi, which specifies the +// interface to join. ListenMulticastUDP uses default multicast +// interface if ifi is nil. +func ListenMulticastUDP(net string, ifi *Interface, gaddr *UDPAddr) (*UDPConn, error) { + switch net { + case "udp", "udp4", "udp6": + default: + return nil, &OpError{Op: "listen", Net: net, Addr: gaddr, Err: UnknownNetworkError(net)} + } + if gaddr == nil || gaddr.IP == nil { + return nil, &OpError{Op: "listen", Net: net, Addr: nil, Err: errMissingAddress} + } + fd, err := internetSocket(net, gaddr, nil, noDeadline, syscall.SOCK_DGRAM, 0, "listen") + if err != nil { + return nil, &OpError{Op: "listen", Net: net, Addr: gaddr, Err: err} + } + c := newUDPConn(fd) + if ip4 := gaddr.IP.To4(); ip4 != nil { + if err := listenIPv4MulticastUDP(c, ifi, ip4); err != nil { + c.Close() + return nil, &OpError{Op: "listen", Net: net, Addr: &IPAddr{IP: ip4}, Err: err} + } + } else { + if err := listenIPv6MulticastUDP(c, ifi, gaddr.IP); err != nil { + c.Close() + return nil, &OpError{Op: "listen", Net: net, Addr: &IPAddr{IP: gaddr.IP}, Err: err} + } + } + return c, nil +} + +func listenIPv4MulticastUDP(c *UDPConn, ifi *Interface, ip IP) error { + if ifi != nil { + if err := setIPv4MulticastInterface(c.fd, ifi); err != nil { + return err + } + } + if err := setIPv4MulticastLoopback(c.fd, false); err != nil { + return err + } + if err := joinIPv4Group(c.fd, ifi, ip); err != nil { + return err + } + return nil +} + +func listenIPv6MulticastUDP(c *UDPConn, ifi *Interface, ip IP) error { + if ifi != nil { + if err := setIPv6MulticastInterface(c.fd, ifi); err != nil { + return err + } + } + if err := setIPv6MulticastLoopback(c.fd, false); err != nil { + return err + } + if err := joinIPv6Group(c.fd, ifi, ip); err != nil { + return err + } + return nil +} |