| // 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"; |
| "reflect"; |
| "strconv"; |
| "strings"; |
| "syscall"; |
| ) |
| |
| var errMissingAddress = os.ErrorString("missing address") |
| |
| type OpError struct { |
| Op string; |
| Net string; |
| Addr string; |
| Error os.Error; |
| } |
| |
| func (e *OpError) String() string { |
| s := e.Op; |
| if e.Net != "" { |
| s += " " + e.Net; |
| } |
| if e.Addr != "" { |
| s += " " + e.Addr; |
| } |
| s += ": " + e.Error.String(); |
| return s; |
| } |
| |
| type AddrError struct { |
| Error string; |
| Addr string; |
| } |
| |
| func (e *AddrError) String() string { |
| s := e.Error; |
| if e.Addr != "" { |
| s += " " + e.Addr; |
| } |
| return s; |
| } |
| |
| type UnknownNetworkError string |
| func (e UnknownNetworkError) String() string { |
| return "unknown network " + string(e); |
| } |
| |
| // 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; |
| |
| // LocalAddr returns the local network address. |
| LocalAddr() string; |
| |
| // RemoteAddr returns the remote network address. |
| RemoteAddr() string; |
| |
| // 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) |
| func LookupPort(network, service string) (port int, 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. |
| i := strings.LastIndex(hostport, ":"); |
| if i < 0 { |
| err = &AddrError{"missing port in address", hostport}; |
| return; |
| } |
| |
| host, port = hostport[0:i], 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 { |
| err = &AddrError{"too many colons in address", hostport}; |
| return; |
| } |
| } |
| return; |
| } |
| |
| // 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) { |
| host, port, err := splitHostPort(hostport); |
| if err != nil { |
| goto Error; |
| } |
| |
| var addr IP; |
| if host == "" { |
| if mode != "listen" { |
| err = &AddrError{"no host in address", hostport}; |
| goto Error; |
| } |
| if preferIPv4 { |
| addr = IPv4zero; |
| } else { |
| addr = IPzero; // wildcard - listen to all |
| } |
| } |
| |
| // 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, err1 := LookupHost(host); |
| if err1 != nil { |
| err = err1; |
| goto Error; |
| } |
| addr = ParseIP(addrs[0]); |
| if addr == nil { |
| // should not happen |
| err = &AddrError{"LookupHost returned invalid address", addrs[0]}; |
| goto Error; |
| } |
| } |
| |
| p, i, ok := dtoi(port, 0); |
| if !ok || i != len(port) { |
| p, err = LookupPort(net, port); |
| if err != nil { |
| goto Error; |
| } |
| } |
| if p < 0 || p > 0xFFFF { |
| err = &AddrError{"invalid port", port}; |
| goto Error; |
| } |
| |
| return addr, p, nil; |
| |
| Error: |
| return nil, 0, err; |
| } |
| |
| type UnknownSocketError struct { |
| sa syscall.Sockaddr; |
| } |
| func (e *UnknownSocketError) String() string { |
| return "unknown socket address type " + reflect.Typeof(e.sa).String() |
| } |
| |
| 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 "", &UnknownSocketError{sa}; |
| } |
| |
| 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.Errno(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.Errno(e) |
| } |
| } |
| |
| if ra != nil { |
| e = syscall.Connect(s, ra); |
| if e != 0 { |
| syscall.Close(s); |
| return nil, os.Errno(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) LocalAddr() string { |
| if c == nil { |
| return "" |
| } |
| return c.fd.addr(); |
| } |
| |
| func (c *connBase) RemoteAddr() string { |
| if c == nil { |
| return "" |
| } |
| return c.fd.remoteAddr(); |
| } |
| |
| 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.NewSyscallError("setsockopt", syscall.SetsockoptInt(fd, level, opt, value)); |
| } |
| |
| func setsockoptNsec(fd, level, opt int, nsec int64) os.Error { |
| var tv = syscall.NsecToTimeval(nsec); |
| return os.NewSyscallError("setsockopt", 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.NewSyscallError("setsockopt", 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; |
| |
| if laddr != "" { |
| if lip, lport, err = hostPortToIP(net, laddr, mode); err != nil { |
| goto Error; |
| } |
| } |
| if raddr != "" { |
| if rip, rport, err = hostPortToIP(net, raddr, mode); err != nil { |
| goto Error; |
| } |
| } |
| |
| // 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 { |
| if la, err = ipToSockaddr(family, lip, lport); err != nil { |
| goto Error; |
| } |
| } |
| if rip != nil { |
| if ra, err = ipToSockaddr(family, rip, rport); err != nil { |
| goto Error; |
| } |
| } |
| |
| fd, err = socket(net, laddr, raddr, family, proto, 0, la, ra); |
| if err != nil { |
| goto Error; |
| } |
| return fd, nil; |
| |
| Error: |
| addr := raddr; |
| if mode == "listen" { |
| addr = laddr; |
| } |
| return nil, &OpError{mode, net, addr, 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, &OpError{"dial", "tcp", "", errMissingAddress} |
| } |
| 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, &OpError{"dial", "udp", "", errMissingAddress} |
| } |
| 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, UnknownNetworkError(net); |
| case "unix": |
| proto = syscall.SOCK_STREAM; |
| case "unix-dgram": |
| proto = syscall.SOCK_DGRAM; |
| } |
| |
| var la, ra syscall.Sockaddr; |
| switch mode { |
| default: |
| panic("unixSocket", mode); |
| |
| case "dial": |
| if laddr != "" { |
| return nil, &OpError{mode, net, raddr, &AddrError{"unexpected local address", laddr}} |
| } |
| if raddr == "" { |
| return nil, &OpError{mode, net, "", errMissingAddress} |
| } |
| ra = &syscall.SockaddrUnix{Name: raddr}; |
| |
| case "listen": |
| if laddr == "" { |
| return nil, &OpError{mode, net, "", errMissingAddress} |
| } |
| la = &syscall.SockaddrUnix{Name: laddr}; |
| if raddr != "" { |
| return nil, &OpError{mode, net, laddr, &AddrError{"unexpected remote address", raddr}} |
| } |
| } |
| |
| fd, err = socket(net, laddr, raddr, syscall.AF_UNIX, proto, 0, la, ra); |
| if err != nil { |
| goto Error; |
| } |
| return fd, nil; |
| |
| Error: |
| addr := raddr; |
| if mode == "listen" { |
| addr = laddr; |
| } |
| return nil, &OpError{mode, net, addr, 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 { |
| if pe, ok := e.(*os.PathError); ok { |
| e = pe.Error; |
| } |
| // 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 pe, ok := e1.(*os.PathError); ok { |
| e1 = pe.Error; |
| } |
| 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, &OpError{"listen", "unix", laddr, os.Errno(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; |
| } |
| |
| // Addr returns the listener's network address. |
| func (l *ListenerUnix) Addr() string { |
| return l.fd.addr(); |
| } |
| |
| // 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, &OpError{"dial", net, raddr, UnknownNetworkError(net)}; |
| } |
| |
| // 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; |
| Addr() string; // Listener's network address |
| } |
| |
| // ListenerTCP is a TCP network listener. |
| // Clients should typically use variables of type Listener |
| // instead of assuming TCP. |
| type ListenerTCP struct { |
| fd *netFD; |
| } |
| |
| // ListenTCP announces on the TCP address laddr and returns a TCP listener. |
| // Net must be "tcp", "tcp4", or "tcp6". |
| // If laddr has a port of 0, it means to listen on some available port. |
| // The caller can use l.Addr() to retrieve the chosen address. |
| 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, &OpError{"listen", "tcp", laddr, os.Errno(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() |
| } |
| |
| // Addr returns the listener's network address. |
| func (l *ListenerTCP) Addr() string { |
| return l.fd.addr(); |
| } |
| |
| // 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, UnknownNetworkError(net); |
| } |
| |