Subversion Repositories openrisc

// 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 freebsd linux netbsd openbsd windows

// TCP sockets

package net

import (

        "io"

        "os"

        "syscall"

        "time"

)

// BUG(rsc): On OpenBSD, listening on the "tcp" network does not listen for

// both IPv4 and IPv6 connections. This is due to the fact that IPv4 traffic

// will not be routed to an IPv6 socket - two separate sockets are required

// if both AFs are to be supported. See inet6(4) on OpenBSD for details.

func sockaddrToTCP(sa syscall.Sockaddr) Addr {

        switch sa := sa.(type) {

        case *syscall.SockaddrInet4:

                return &TCPAddr{sa.Addr[0:], sa.Port}

        case *syscall.SockaddrInet6:

                return &TCPAddr{sa.Addr[0:], sa.Port}

        }

        return nil

}

func (a *TCPAddr) 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 *TCPAddr) sockaddr(family int) (syscall.Sockaddr, error) {

        return ipToSockaddr(family, a.IP, a.Port)

}

func (a *TCPAddr) toAddr() sockaddr {

        if a == nil { // nil *TCPAddr

                return nil // nil interface

        }

        return a

}

// TCPConn is an implementation of the Conn interface

// for TCP network connections.

type TCPConn struct {

        fd *netFD

}

func newTCPConn(fd *netFD) *TCPConn {

        c := &TCPConn{fd}

        c.SetNoDelay(true)

        return c

}

func (c *TCPConn) ok() bool { return c != nil && c.fd != nil }

// Implementation of the Conn interface - see Conn for documentation.

// Read implements the Conn Read method.

func (c *TCPConn) Read(b []byte) (n int, err error) {

        if !c.ok() {

                return 0, os.EINVAL

        }

        return c.fd.Read(b)

}

// ReadFrom implements the io.ReaderFrom ReadFrom method.

func (c *TCPConn) ReadFrom(r io.Reader) (int64, error) {

        if n, err, handled := sendFile(c.fd, r); handled {

                return n, err

        }

        return genericReadFrom(c, r)

}

// Write implements the Conn Write method.

func (c *TCPConn) Write(b []byte) (n int, err error) {

        if !c.ok() {

                return 0, os.EINVAL

        }

        return c.fd.Write(b)

}

// Close closes the TCP connection.

func (c *TCPConn) Close() error {

        if !c.ok() {

                return os.EINVAL

        }

        err := c.fd.Close()

        c.fd = nil

        return err

}

// CloseRead shuts down the reading side of the TCP connection.

// Most callers should just use Close.

func (c *TCPConn) CloseRead() error {

        if !c.ok() {

                return os.EINVAL

        }

        return c.fd.CloseRead()

}

// CloseWrite shuts down the writing side of the TCP connection.

// Most callers should just use Close.

func (c *TCPConn) CloseWrite() error {

        if !c.ok() {

                return os.EINVAL

        }

        return c.fd.CloseWrite()

}

// LocalAddr returns the local network address, a *TCPAddr.

func (c *TCPConn) LocalAddr() Addr {

        if !c.ok() {

                return nil

        }

        return c.fd.laddr

}

// RemoteAddr returns the remote network address, a *TCPAddr.

func (c *TCPConn) RemoteAddr() Addr {

        if !c.ok() {

                return nil

        }

        return c.fd.raddr

}

// SetDeadline implements the Conn SetDeadline method.

func (c *TCPConn) SetDeadline(t time.Time) error {

        if !c.ok() {

                return os.EINVAL

        }

        return setDeadline(c.fd, t)

}

// SetReadDeadline implements the Conn SetReadDeadline method.

func (c *TCPConn) SetReadDeadline(t time.Time) error {

        if !c.ok() {

                return os.EINVAL

        }

        return setReadDeadline(c.fd, t)

}

// SetWriteDeadline implements the Conn SetWriteDeadline method.

func (c *TCPConn) SetWriteDeadline(t time.Time) error {

        if !c.ok() {

                return os.EINVAL

        }

        return setWriteDeadline(c.fd, t)

}

// SetReadBuffer sets the size of the operating system's

// receive buffer associated with the connection.

func (c *TCPConn) SetReadBuffer(bytes int) 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 *TCPConn) SetWriteBuffer(bytes int) error {

        if !c.ok() {

                return os.EINVAL

        }

        return setWriteBuffer(c.fd, bytes)

}

// 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.

func (c *TCPConn) SetLinger(sec int) error {

        if !c.ok() {

                return os.EINVAL

        }

        return setLinger(c.fd, sec)

}

// SetKeepAlive sets whether the operating system should send

// keepalive messages on the connection.

func (c *TCPConn) SetKeepAlive(keepalive bool) error {

        if !c.ok() {

                return os.EINVAL

        }

        return setKeepAlive(c.fd, keepalive)

}

// SetNoDelay controls whether the operating system should delay

// packet transmission in hopes of sending fewer packets

// (Nagle's algorithm).  The default is true (no delay), meaning

// that data is sent as soon as possible after a Write.

func (c *TCPConn) SetNoDelay(noDelay bool) error {

        if !c.ok() {

                return os.EINVAL

        }

        return setNoDelay(c.fd, noDelay)

}

// 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 *TCPConn) File() (f *os.File, err error) { return c.fd.dup() }

// DialTCP connects to the remote address raddr on the network net,

// which must be "tcp", "tcp4", or "tcp6".  If laddr is not nil, it is used

// as the local address for the connection.

func DialTCP(net string, laddr, raddr *TCPAddr) (*TCPConn, error) {

        if raddr == nil {

                return nil, &OpError{"dial", net, nil, errMissingAddress}

        }

        fd, err := internetSocket(net, laddr.toAddr(), raddr.toAddr(), syscall.SOCK_STREAM, 0, "dial", sockaddrToTCP)

        if err != nil {

                return nil, err

        }

        return newTCPConn(fd), nil

}

// TCPListener is a TCP network listener.

// Clients should typically use variables of type Listener

// instead of assuming TCP.

type TCPListener 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 string, laddr *TCPAddr) (*TCPListener, error) {

        fd, err := internetSocket(net, laddr.toAddr(), nil, syscall.SOCK_STREAM, 0, "listen", sockaddrToTCP)

        if err != nil {

                return nil, err

        }

        err = syscall.Listen(fd.sysfd, listenerBacklog)

        if err != nil {

                closesocket(fd.sysfd)

                return nil, &OpError{"listen", net, laddr, err}

        }

        l := new(TCPListener)

        l.fd = fd

        return l, nil

}

// AcceptTCP accepts the next incoming call and returns the new connection

// and the remote address.

func (l *TCPListener) AcceptTCP() (c *TCPConn, err error) {

        if l == nil || l.fd == nil || l.fd.sysfd < 0 {

                return nil, os.EINVAL

        }

        fd, err := l.fd.accept(sockaddrToTCP)

        if err != nil {

                return nil, err

        }

        return newTCPConn(fd), nil

}

// Accept implements the Accept method in the Listener interface;

// it waits for the next call and returns a generic Conn.

func (l *TCPListener) Accept() (c Conn, err error) {

        c1, err := l.AcceptTCP()

        if err != nil {

                return nil, err

        }

        return c1, nil

}

// Close stops listening on the TCP address.

// Already Accepted connections are not closed.

func (l *TCPListener) Close() error {

        if l == nil || l.fd == nil {

                return os.EINVAL

        }

        return l.fd.Close()

}

// Addr returns the listener's network address, a *TCPAddr.

func (l *TCPListener) Addr() Addr { return l.fd.laddr }

// SetDeadline sets the deadline associated with the listener.

// A zero time value disables the deadline.

func (l *TCPListener) SetDeadline(t time.Time) error {

        if l == nil || l.fd == nil {

                return os.EINVAL

        }

        return setDeadline(l.fd, t)

}

// 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 (l *TCPListener) File() (f *os.File, err error) { return l.fd.dup() }