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-rw-r--r--src/pkg/net/net.go862
1 files changed, 862 insertions, 0 deletions
diff --git a/src/pkg/net/net.go b/src/pkg/net/net.go
new file mode 100644
index 000000000..5c442e6a4
--- /dev/null
+++ b/src/pkg/net/net.go
@@ -0,0 +1,862 @@
+// 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.
+
+package net
+
+import (
+ "net";
+ "os";
+ "strconv";
+ "syscall";
+)
+
+var (
+ BadAddress os.Error = &Error{"malformed address"};
+ MissingAddress os.Error = &Error{"missing address"};
+ UnknownNetwork os.Error = &Error{"unknown network"};
+ UnknownHost os.Error = &Error{"unknown host"};
+ UnknownSocketFamily os.Error = &Error{"unknown socket family"};
+)
+
+
+// Conn is a generic network connection.
+type Conn interface {
+ // Read blocks until data is ready from the connection
+ // and then reads into b. It returns the number
+ // of bytes read, or 0 if the connection has been closed.
+ Read(b []byte) (n int, err os.Error);
+
+ // Write writes the data in b to the connection.
+ Write(b []byte) (n int, err os.Error);
+
+ // Close closes the connection.
+ Close() os.Error;
+
+ // For packet-based protocols such as UDP,
+ // ReadFrom reads the next packet from the network,
+ // returning the number of bytes read and the remote
+ // address that sent them.
+ ReadFrom(b []byte) (n int, addr string, err os.Error);
+
+ // For packet-based protocols such as UDP,
+ // WriteTo writes the byte buffer b to the network
+ // as a single payload, sending it to the target address.
+ WriteTo(addr string, b []byte) (n int, err os.Error);
+
+ // SetReadBuffer sets the size of the operating system's
+ // receive buffer associated with the connection.
+ SetReadBuffer(bytes int) os.Error;
+
+ // SetReadBuffer sets the size of the operating system's
+ // transmit buffer associated with the connection.
+ SetWriteBuffer(bytes int) os.Error;
+
+ // SetTimeout sets the read and write deadlines associated
+ // with the connection.
+ SetTimeout(nsec int64) os.Error;
+
+ // SetReadTimeout sets the time (in nanoseconds) that
+ // Read will wait for data before returning os.EAGAIN.
+ // Setting nsec == 0 (the default) disables the deadline.
+ SetReadTimeout(nsec int64) os.Error;
+
+ // SetWriteTimeout sets the time (in nanoseconds) that
+ // Write will wait to send its data before returning os.EAGAIN.
+ // Setting nsec == 0 (the default) disables the deadline.
+ // Even if write times out, it may return n > 0, indicating that
+ // some of the data was successfully written.
+ SetWriteTimeout(nsec int64) os.Error;
+
+ // SetLinger sets the behavior of Close() on a connection
+ // which still has data waiting to be sent or to be acknowledged.
+ //
+ // If sec < 0 (the default), Close returns immediately and
+ // the operating system finishes sending the data in the background.
+ //
+ // If sec == 0, Close returns immediately and the operating system
+ // discards any unsent or unacknowledged data.
+ //
+ // If sec > 0, Close blocks for at most sec seconds waiting for
+ // data to be sent and acknowledged.
+ SetLinger(sec int) os.Error;
+
+ // SetReuseAddr sets whether it is okay to reuse addresses
+ // from recent connections that were not properly closed.
+ SetReuseAddr(reuseaddr bool) os.Error;
+
+ // SetDontRoute sets whether outgoing messages should
+ // bypass the system routing tables.
+ SetDontRoute(dontroute bool) os.Error;
+
+ // SetKeepAlive sets whether the operating system should send
+ // keepalive messages on the connection.
+ SetKeepAlive(keepalive bool) os.Error;
+
+ // BindToDevice binds a connection to a particular network device.
+ BindToDevice(dev string) os.Error;
+}
+
+// Should we try to use the IPv4 socket interface if we're
+// only dealing with IPv4 sockets? As long as the host system
+// understands IPv6, it's okay to pass IPv4 addresses to the IPv6
+// interface. That simplifies our code and is most general.
+// Unfortunately, we need to run on kernels built without IPv6 support too.
+// So probe the kernel to figure it out.
+func kernelSupportsIPv6() bool {
+ fd, e := syscall.Socket(syscall.AF_INET6, syscall.SOCK_STREAM, syscall.IPPROTO_TCP);
+ if fd >= 0 {
+ syscall.Close(fd)
+ }
+ return e == 0
+}
+
+var preferIPv4 = !kernelSupportsIPv6()
+
+// TODO(rsc): if syscall.OS == "linux", we're supposd to read
+// /proc/sys/net/core/somaxconn,
+// to take advantage of kernels that have raised the limit.
+func listenBacklog() int {
+ return syscall.SOMAXCONN
+}
+
+func LookupHost(name string) (cname string, addrs []string, err os.Error)
+
+// Split "host:port" into "host" and "port".
+// Host cannot contain colons unless it is bracketed.
+func splitHostPort(hostport string) (host, port string, err os.Error) {
+ // The port starts after the last colon.
+ var i int;
+ for i = len(hostport)-1; i >= 0; i-- {
+ if hostport[i] == ':' {
+ break
+ }
+ }
+ if i < 0 {
+ return "", "", BadAddress
+ }
+
+ host = hostport[0:i];
+ port = hostport[i+1:len(hostport)];
+
+ // Can put brackets around host ...
+ if len(host) > 0 && host[0] == '[' && host[len(host)-1] == ']' {
+ host = host[1:len(host)-1]
+ } else {
+ // ... but if there are no brackets, no colons.
+ if byteIndex(host, ':') >= 0 {
+ return "", "", BadAddress
+ }
+ }
+ return host, port, nil
+}
+
+// Join "host" and "port" into "host:port".
+// If host contains colons, will join into "[host]:port".
+func joinHostPort(host, port string) string {
+ // If host has colons, have to bracket it.
+ if byteIndex(host, ':') >= 0 {
+ return "[" + host + "]:" + port
+ }
+ return host + ":" + port
+}
+
+// Convert "host:port" into IP address and port.
+// For now, host and port must be numeric literals.
+// Eventually, we'll have name resolution.
+func hostPortToIP(net, hostport, mode string) (ip IP, iport int, err os.Error) {
+ var host, port string;
+ host, port, err = splitHostPort(hostport);
+ if err != nil {
+ return nil, 0, err
+ }
+
+ var addr IP;
+ if host == "" {
+ if mode == "listen" {
+ if preferIPv4 {
+ addr = IPv4zero;
+ } else {
+ addr = IPzero; // wildcard - listen to all
+ }
+ } else {
+ return nil, 0, MissingAddress;
+ }
+ }
+
+ // Try as an IP address.
+ if addr == nil {
+ addr = ParseIP(host);
+ }
+ if addr == nil {
+ // Not an IP address. Try as a DNS name.
+ hostname, addrs, err := LookupHost(host);
+ if err != nil {
+ return nil, 0, err
+ }
+ if len(addrs) == 0 {
+ return nil, 0, UnknownHost
+ }
+ addr = ParseIP(addrs[0]);
+ if addr == nil {
+ // should not happen
+ return nil, 0, BadAddress
+ }
+ }
+
+ p, i, ok := dtoi(port, 0);
+ if !ok || i != len(port) {
+ p, err = LookupPort(net, port);
+ if err != nil {
+ return nil, 0, err
+ }
+ }
+ if p < 0 || p > 0xFFFF {
+ return nil, 0, BadAddress
+ }
+
+ return addr, p, nil
+}
+
+func sockaddrToString(sa syscall.Sockaddr) (name string, err os.Error) {
+ switch a := sa.(type) {
+ case *syscall.SockaddrInet4:
+ return joinHostPort(IP(&a.Addr).String(), strconv.Itoa(a.Port)), nil;
+ case *syscall.SockaddrInet6:
+ return joinHostPort(IP(&a.Addr).String(), strconv.Itoa(a.Port)), nil;
+ case *syscall.SockaddrUnix:
+ return a.Name, nil;
+ }
+ return "", UnknownSocketFamily
+}
+
+func ipToSockaddr(family int, ip IP, port int) (syscall.Sockaddr, os.Error) {
+ switch family {
+ case syscall.AF_INET:
+ if ip = ip.To4(); ip == nil {
+ return nil, os.EINVAL
+ }
+ s := new(syscall.SockaddrInet4);
+ for i := 0; i < IPv4len; i++ {
+ s.Addr[i] = ip[i];
+ }
+ s.Port = port;
+ return s, nil;
+ case syscall.AF_INET6:
+ // IPv4 callers use 0.0.0.0 to mean "announce on any available address".
+ // In IPv6 mode, Linux treats that as meaning "announce on 0.0.0.0",
+ // which it refuses to do. Rewrite to the IPv6 all zeros.
+ if p4 := ip.To4(); p4 != nil && p4[0] == 0 && p4[1] == 0 && p4[2] == 0 && p4[3] == 0 {
+ ip = IPzero;
+ }
+ if ip = ip.To16(); ip == nil {
+ return nil, os.EINVAL
+ }
+ s := new(syscall.SockaddrInet6);
+ for i := 0; i < IPv6len; i++ {
+ s.Addr[i] = ip[i];
+ }
+ s.Port = port;
+ return s, nil;
+ }
+ return nil, os.EINVAL;
+}
+
+// Boolean to int.
+func boolint(b bool) int {
+ if b {
+ return 1
+ }
+ return 0
+}
+
+// Generic socket creation.
+func socket(net, laddr, raddr string, f, p, t int, la, ra syscall.Sockaddr) (fd *netFD, err os.Error) {
+ // See ../syscall/exec.go for description of ForkLock.
+ syscall.ForkLock.RLock();
+ s, e := syscall.Socket(f, p, t);
+ if e != 0 {
+ syscall.ForkLock.RUnlock();
+ return nil, os.ErrnoToError(e)
+ }
+ syscall.CloseOnExec(s);
+ syscall.ForkLock.RUnlock();
+
+ // Allow reuse of recently-used addresses.
+ syscall.SetsockoptInt(s, syscall.SOL_SOCKET, syscall.SO_REUSEADDR, 1);
+
+ var r int64;
+ if la != nil {
+ e = syscall.Bind(s, la);
+ if e != 0 {
+ syscall.Close(s);
+ return nil, os.ErrnoToError(e)
+ }
+ }
+
+ if ra != nil {
+ e = syscall.Connect(s, ra);
+ if e != 0 {
+ syscall.Close(s);
+ return nil, os.ErrnoToError(e)
+ }
+ }
+
+ fd, err = newFD(s, net, laddr, raddr);
+ if err != nil {
+ syscall.Close(s);
+ return nil, err
+ }
+
+ return fd, nil
+}
+
+
+// Generic implementation of Conn interface; not exported.
+type connBase struct {
+ fd *netFD;
+ raddr string;
+}
+
+func (c *connBase) File() *os.File {
+ if c == nil {
+ return nil
+ }
+ return c.fd.file;
+}
+
+func (c *connBase) sysFD() int {
+ if c == nil || c.fd == nil {
+ return -1;
+ }
+ return c.fd.fd;
+}
+
+func (c *connBase) Read(b []byte) (n int, err os.Error) {
+ n, err = c.fd.Read(b);
+ return n, err
+}
+
+func (c *connBase) Write(b []byte) (n int, err os.Error) {
+ n, err = c.fd.Write(b);
+ return n, err
+}
+
+func (c *connBase) ReadFrom(b []byte) (n int, raddr string, err os.Error) {
+ if c == nil {
+ return -1, "", os.EINVAL
+ }
+ n, err = c.Read(b);
+ return n, c.raddr, err
+}
+
+func (c *connBase) WriteTo(raddr string, b []byte) (n int, err os.Error) {
+ if c == nil {
+ return -1, os.EINVAL
+ }
+ if raddr != c.raddr {
+ return -1, os.EINVAL
+ }
+ n, err = c.Write(b);
+ return n, err
+}
+
+func (c *connBase) Close() os.Error {
+ if c == nil {
+ return os.EINVAL
+ }
+ return c.fd.Close()
+}
+
+
+func setsockoptInt(fd, level, opt int, value int) os.Error {
+ return os.ErrnoToError(syscall.SetsockoptInt(fd, level, opt, value));
+}
+
+func setsockoptNsec(fd, level, opt int, nsec int64) os.Error {
+ var tv = syscall.NsecToTimeval(nsec);
+ return os.ErrnoToError(syscall.SetsockoptTimeval(fd, level, opt, &tv));
+}
+
+func (c *connBase) SetReadBuffer(bytes int) os.Error {
+ return setsockoptInt(c.sysFD(), syscall.SOL_SOCKET, syscall.SO_RCVBUF, bytes);
+}
+
+func (c *connBase) SetWriteBuffer(bytes int) os.Error {
+ return setsockoptInt(c.sysFD(), syscall.SOL_SOCKET, syscall.SO_SNDBUF, bytes);
+}
+
+func (c *connBase) SetReadTimeout(nsec int64) os.Error {
+ c.fd.rdeadline_delta = nsec;
+ return nil;
+}
+
+func (c *connBase) SetWriteTimeout(nsec int64) os.Error {
+ c.fd.wdeadline_delta = nsec;
+ return nil;
+}
+
+func (c *connBase) SetTimeout(nsec int64) os.Error {
+ if e := c.SetReadTimeout(nsec); e != nil {
+ return e
+ }
+ return c.SetWriteTimeout(nsec)
+}
+
+func (c *connBase) SetReuseAddr(reuse bool) os.Error {
+ return setsockoptInt(c.sysFD(), syscall.SOL_SOCKET, syscall.SO_REUSEADDR, boolint(reuse));
+}
+
+func (c *connBase) BindToDevice(dev string) os.Error {
+ // TODO(rsc): call setsockopt with null-terminated string pointer
+ return os.EINVAL
+}
+
+func (c *connBase) SetDontRoute(dontroute bool) os.Error {
+ return setsockoptInt(c.sysFD(), syscall.SOL_SOCKET, syscall.SO_DONTROUTE, boolint(dontroute));
+}
+
+func (c *connBase) SetKeepAlive(keepalive bool) os.Error {
+ return setsockoptInt(c.sysFD(), syscall.SOL_SOCKET, syscall.SO_KEEPALIVE, boolint(keepalive));
+}
+
+func (c *connBase) SetLinger(sec int) os.Error {
+ var l syscall.Linger;
+ if sec >= 0 {
+ l.Onoff = 1;
+ l.Linger = int32(sec);
+ } else {
+ l.Onoff = 0;
+ l.Linger = 0;
+ }
+ e := syscall.SetsockoptLinger(c.sysFD(), syscall.SOL_SOCKET, syscall.SO_LINGER, &l);
+ return os.ErrnoToError(e);
+}
+
+
+// Internet sockets (TCP, UDP)
+
+func internetSocket(net, laddr, raddr string, proto int, mode string) (fd *netFD, err os.Error) {
+ // Parse addresses (unless they are empty).
+ var lip, rip IP;
+ var lport, rport int;
+ var lerr, rerr os.Error;
+
+ if laddr != "" {
+ lip, lport, lerr = hostPortToIP(net, laddr, mode);
+ if lerr != nil {
+ return nil, lerr
+ }
+ }
+ if raddr != "" {
+ rip, rport, rerr = hostPortToIP(net, raddr, mode);
+ if rerr != nil {
+ return nil, rerr
+ }
+ }
+
+ // Figure out IP version.
+ // If network has a suffix like "tcp4", obey it.
+ vers := 0;
+ switch net[len(net)-1] {
+ case '4':
+ vers = 4;
+ case '6':
+ vers = 6;
+ default:
+ // Otherwise, guess.
+ // If the addresses are IPv4 and we prefer IPv4, use 4; else 6.
+ if preferIPv4 && (lip == nil || lip.To4() != nil) && (rip == nil || rip.To4() != nil) {
+ vers = 4
+ } else {
+ vers = 6
+ }
+ }
+
+ var family int;
+ if vers == 4 {
+ family = syscall.AF_INET
+ } else {
+ family = syscall.AF_INET6
+ }
+
+ var la, ra syscall.Sockaddr;
+ if lip != nil {
+ la, lerr = ipToSockaddr(family, lip, lport);
+ if lerr != nil {
+ return nil, lerr
+ }
+ }
+ if rip != nil {
+ ra, rerr = ipToSockaddr(family, rip, rport);
+ if rerr != nil {
+ return nil, rerr
+ }
+ }
+
+ fd, err = socket(net, laddr, raddr, family, proto, 0, la, ra);
+ return fd, err
+}
+
+
+// TCP connections.
+
+// ConnTCP is an implementation of the Conn interface
+// for TCP network connections.
+type ConnTCP struct {
+ connBase
+}
+
+func (c *ConnTCP) SetNoDelay(nodelay bool) os.Error {
+ if c == nil {
+ return os.EINVAL
+ }
+ return setsockoptInt(c.sysFD(), syscall.IPPROTO_TCP, syscall.TCP_NODELAY, boolint(nodelay))
+}
+
+func newConnTCP(fd *netFD, raddr string) *ConnTCP {
+ c := new(ConnTCP);
+ c.fd = fd;
+ c.raddr = raddr;
+ c.SetNoDelay(true);
+ return c
+}
+
+// DialTCP is like Dial but can only connect to TCP networks
+// and returns a ConnTCP structure.
+func DialTCP(net, laddr, raddr string) (c *ConnTCP, err os.Error) {
+ if raddr == "" {
+ return nil, MissingAddress
+ }
+ fd, e := internetSocket(net, laddr, raddr, syscall.SOCK_STREAM, "dial");
+ if e != nil {
+ return nil, e
+ }
+ return newConnTCP(fd, raddr), nil
+}
+
+
+// UDP connections.
+
+// TODO(rsc): UDP headers mode
+
+// ConnUDP is an implementation of the Conn interface
+// for UDP network connections.
+type ConnUDP struct {
+ connBase
+}
+
+func newConnUDP(fd *netFD, raddr string) *ConnUDP {
+ c := new(ConnUDP);
+ c.fd = fd;
+ c.raddr = raddr;
+ return c
+}
+
+// DialUDP is like Dial but can only connect to UDP networks
+// and returns a ConnUDP structure.
+func DialUDP(net, laddr, raddr string) (c *ConnUDP, err os.Error) {
+ if raddr == "" {
+ return nil, MissingAddress
+ }
+ fd, e := internetSocket(net, laddr, raddr, syscall.SOCK_DGRAM, "dial");
+ if e != nil {
+ return nil, e
+ }
+ return newConnUDP(fd, raddr), nil
+}
+
+
+// TODO: raw IP connections
+
+// TODO: raw ethernet connections
+
+
+// Unix domain sockets
+
+func unixSocket(net, laddr, raddr string, mode string) (fd *netFD, err os.Error) {
+ var proto int;
+ switch net {
+ default:
+ return nil, UnknownNetwork;
+ case "unix":
+ proto = syscall.SOCK_STREAM;
+ case "unix-dgram":
+ proto = syscall.SOCK_DGRAM;
+ }
+
+ var la, ra syscall.Sockaddr;
+ switch mode {
+ case "dial":
+ if laddr != "" {
+ return nil, BadAddress;
+ }
+ if raddr == "" {
+ return nil, MissingAddress;
+ }
+ ra = &syscall.SockaddrUnix{Name: raddr};
+
+ case "listen":
+ if laddr == "" {
+ return nil, MissingAddress;
+ }
+ la = &syscall.SockaddrUnix{Name: laddr};
+ if raddr != "" {
+ return nil, BadAddress;
+ }
+ }
+
+ fd, err = socket(net, laddr, raddr, syscall.AF_UNIX, proto, 0, la, ra);
+ return fd, err
+}
+
+// ConnUnix is an implementation of the Conn interface
+// for connections to Unix domain sockets.
+type ConnUnix struct {
+ connBase
+}
+
+func newConnUnix(fd *netFD, raddr string) *ConnUnix {
+ c := new(ConnUnix);
+ c.fd = fd;
+ c.raddr = raddr;
+ return c;
+}
+
+// DialUnix is like Dial but can only connect to Unix domain sockets
+// and returns a ConnUnix structure. The laddr argument must be
+// the empty string; it is included only to match the signature of
+// the other dial routines.
+func DialUnix(net, laddr, raddr string) (c *ConnUnix, err os.Error) {
+ fd, e := unixSocket(net, laddr, raddr, "dial");
+ if e != nil {
+ return nil, e
+ }
+ return newConnUnix(fd, raddr), nil;
+}
+
+// ListenerUnix is a Unix domain socket listener.
+// Clients should typically use variables of type Listener
+// instead of assuming Unix domain sockets.
+type ListenerUnix struct {
+ fd *netFD;
+ laddr string
+}
+
+// ListenUnix announces on the Unix domain socket laddr and returns a Unix listener.
+// Net can be either "unix" (stream sockets) or "unix-dgram" (datagram sockets).
+func ListenUnix(net, laddr string) (l *ListenerUnix, err os.Error) {
+ fd, e := unixSocket(net, laddr, "", "listen");
+ if e != nil {
+ // Check for socket ``in use'' but ``refusing connections,''
+ // which means some program created it and exited
+ // without unlinking it from the file system.
+ // Clean up on that program's behalf and try again.
+ // Don't do this for Linux's ``abstract'' sockets, which begin with @.
+ if e != os.EADDRINUSE || laddr[0] == '@' {
+ return nil, e;
+ }
+ fd1, e1 := unixSocket(net, "", laddr, "dial");
+ if e1 == nil {
+ fd1.Close();
+ }
+ if e1 != os.ECONNREFUSED {
+ return nil, e;
+ }
+ syscall.Unlink(laddr);
+ fd1, e1 = unixSocket(net, laddr, "", "listen");
+ if e1 != nil {
+ return nil, e;
+ }
+ fd = fd1;
+ }
+ e1 := syscall.Listen(fd.fd, 8); // listenBacklog());
+ if e1 != 0 {
+ syscall.Close(fd.fd);
+ return nil, os.ErrnoToError(e1);
+ }
+ return &ListenerUnix{fd, laddr}, nil;
+}
+
+// AcceptUnix accepts the next incoming call and returns the new connection
+// and the remote address.
+func (l *ListenerUnix) AcceptUnix() (c *ConnUnix, raddr string, err os.Error) {
+ if l == nil || l.fd == nil || l.fd.fd < 0 {
+ return nil, "", os.EINVAL
+ }
+ fd, e := l.fd.accept();
+ if e != nil {
+ return nil, "", e
+ }
+ return newConnUnix(fd, fd.raddr), raddr, nil
+}
+
+// Accept implements the Accept method in the Listener interface;
+// it waits for the next call and returns a generic Conn.
+func (l *ListenerUnix) Accept() (c Conn, raddr string, err os.Error) {
+ // TODO(rsc): 6g bug prevents saying
+ // c, raddr, err = l.AcceptUnix();
+ // return;
+ c1, r1, e1 := l.AcceptUnix();
+ return c1, r1, e1;
+}
+
+
+// Close stops listening on the Unix address.
+// Already accepted connections are not closed.
+func (l *ListenerUnix) Close() os.Error {
+ if l == nil || l.fd == nil {
+ return os.EINVAL
+ }
+
+ // The operating system doesn't clean up
+ // the file that announcing created, so
+ // we have to clean it up ourselves.
+ // There's a race here--we can't know for
+ // sure whether someone else has come along
+ // and replaced our socket name already--
+ // but this sequence (remove then close)
+ // is at least compatible with the auto-remove
+ // sequence in ListenUnix. It's only non-Go
+ // programs that can mess us up.
+ if l.laddr[0] != '@' {
+ syscall.Unlink(l.laddr);
+ }
+ err := l.fd.Close();
+ l.fd = nil;
+ return err;
+}
+
+// Dial connects to the remote address raddr on the network net.
+// If the string laddr is not empty, it is used as the local address
+// for the connection.
+//
+// Known networks are "tcp", "tcp4" (IPv4-only), "tcp6" (IPv6-only),
+// "udp", "udp4" (IPv4-only), and "udp6" (IPv6-only).
+//
+// For IP networks, addresses have the form host:port. If host is
+// a literal IPv6 address, it must be enclosed in square brackets.
+//
+// Examples:
+// Dial("tcp", "", "12.34.56.78:80")
+// Dial("tcp", "", "google.com:80")
+// Dial("tcp", "", "[de:ad:be:ef::ca:fe]:80")
+// Dial("tcp", "127.0.0.1:123", "127.0.0.1:88")
+func Dial(net, laddr, raddr string) (c Conn, err os.Error) {
+ switch net {
+ case "tcp", "tcp4", "tcp6":
+ c, err := DialTCP(net, laddr, raddr);
+ if err != nil {
+ return nil, err
+ }
+ return c, nil;
+ case "udp", "udp4", "upd6":
+ c, err := DialUDP(net, laddr, raddr);
+ return c, err;
+ case "unix", "unix-dgram":
+ c, err := DialUnix(net, laddr, raddr);
+ return c, err;
+/*
+ case "ether":
+ c, err := DialEther(net, laddr, raddr);
+ return c, err;
+ case "ipv4":
+ c, err := DialIPv4(net, laddr, raddr);
+ return c, err;
+ case "ipv6":
+ c, err := DialIPv6(net, laddr, raddr);
+ return c, err
+*/
+ }
+ return nil, UnknownNetwork
+}
+
+// A Listener is a generic network listener.
+// Accept waits for the next connection and Close closes the connection.
+type Listener interface {
+ Accept() (c Conn, raddr string, err os.Error);
+ Close() os.Error;
+}
+
+// ListenerTCP is a TCP network listener.
+// Clients should typically use variables of type Listener
+// instead of assuming TCP.
+type ListenerTCP struct {
+ fd *netFD;
+ laddr string
+}
+
+// ListenTCP announces on the TCP address laddr and returns a TCP listener.
+// Net must be "tcp", "tcp4", or "tcp6".
+func ListenTCP(net, laddr string) (l *ListenerTCP, err os.Error) {
+ fd, e := internetSocket(net, laddr, "", syscall.SOCK_STREAM, "listen");
+ if e != nil {
+ return nil, e
+ }
+ e1 := syscall.Listen(fd.fd, listenBacklog());
+ if e1 != 0 {
+ syscall.Close(fd.fd);
+ return nil, os.ErrnoToError(e1)
+ }
+ l = new(ListenerTCP);
+ l.fd = fd;
+ return l, nil
+}
+
+// AcceptTCP accepts the next incoming call and returns the new connection
+// and the remote address.
+func (l *ListenerTCP) AcceptTCP() (c *ConnTCP, raddr string, err os.Error) {
+ if l == nil || l.fd == nil || l.fd.fd < 0 {
+ return nil, "", os.EINVAL
+ }
+ fd, e := l.fd.accept();
+ if e != nil {
+ return nil, "", e
+ }
+ return newConnTCP(fd, fd.raddr), fd.raddr, nil
+}
+
+// Accept implements the Accept method in the Listener interface;
+// it waits for the next call and returns a generic Conn.
+func (l *ListenerTCP) Accept() (c Conn, raddr string, err os.Error) {
+ c1, r1, e1 := l.AcceptTCP();
+ if e1 != nil {
+ return nil, "", e1
+ }
+ return c1, r1, nil
+}
+
+// Close stops listening on the TCP address.
+// Already Accepted connections are not closed.
+func (l *ListenerTCP) Close() os.Error {
+ if l == nil || l.fd == nil {
+ return os.EINVAL
+ }
+ return l.fd.Close()
+}
+
+// Listen announces on the local network address laddr.
+// The network string net must be "tcp", "tcp4", "tcp6",
+// "unix", or "unix-dgram".
+func Listen(net, laddr string) (l Listener, err os.Error) {
+ switch net {
+ case "tcp", "tcp4", "tcp6":
+ l, err := ListenTCP(net, laddr);
+ if err != nil {
+ return nil, err;
+ }
+ return l, nil;
+ case "unix", "unix-dgram":
+ l, err := ListenUnix(net, laddr);
+ if err != nil {
+ return nil, err;
+ }
+ return l, nil;
+/*
+ more here
+*/
+ // BUG(rsc): Listen should support UDP.
+ }
+ return nil, UnknownNetwork
+}
+
generated by cgit v1.2.3 (git 2.39.1) at 2025-04-28 06:08:05 +0000