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-rw-r--r--src/net/tcpsock.go380
1 files changed, 380 insertions, 0 deletions
diff --git a/src/net/tcpsock.go b/src/net/tcpsock.go
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+++ b/src/net/tcpsock.go
@@ -0,0 +1,380 @@
+// 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 (
+ "context"
+ "internal/itoa"
+ "io"
+ "net/netip"
+ "os"
+ "syscall"
+ "time"
+)
+
+// BUG(mikio): On JS and Windows, the File method of TCPConn and
+// TCPListener is not implemented.
+
+// TCPAddr represents the address of a TCP end point.
+type TCPAddr struct {
+ IP IP
+ Port int
+ Zone string // IPv6 scoped addressing zone
+}
+
+// AddrPort returns the TCPAddr a as a netip.AddrPort.
+//
+// If a.Port does not fit in a uint16, it's silently truncated.
+//
+// If a is nil, a zero value is returned.
+func (a *TCPAddr) AddrPort() netip.AddrPort {
+ if a == nil {
+ return netip.AddrPort{}
+ }
+ na, _ := netip.AddrFromSlice(a.IP)
+ na = na.WithZone(a.Zone)
+ return netip.AddrPortFrom(na, uint16(a.Port))
+}
+
+// Network returns the address's network name, "tcp".
+func (a *TCPAddr) Network() string { return "tcp" }
+
+func (a *TCPAddr) String() string {
+ if a == nil {
+ return "<nil>"
+ }
+ ip := ipEmptyString(a.IP)
+ if a.Zone != "" {
+ return JoinHostPort(ip+"%"+a.Zone, itoa.Itoa(a.Port))
+ }
+ return JoinHostPort(ip, itoa.Itoa(a.Port))
+}
+
+func (a *TCPAddr) isWildcard() bool {
+ if a == nil || a.IP == nil {
+ return true
+ }
+ return a.IP.IsUnspecified()
+}
+
+func (a *TCPAddr) opAddr() Addr {
+ if a == nil {
+ return nil
+ }
+ return a
+}
+
+// ResolveTCPAddr returns an address of TCP end point.
+//
+// The network must be a TCP network name.
+//
+// If the host in the address parameter is not a literal IP address or
+// the port is not a literal port number, ResolveTCPAddr resolves the
+// address to an address of TCP end point.
+// Otherwise, it parses the address as a pair of literal IP address
+// and port number.
+// The address parameter can use a host name, but this is not
+// recommended, because it will return at most one of the host name's
+// IP addresses.
+//
+// See func Dial for a description of the network and address
+// parameters.
+func ResolveTCPAddr(network, address string) (*TCPAddr, error) {
+ switch network {
+ case "tcp", "tcp4", "tcp6":
+ case "": // a hint wildcard for Go 1.0 undocumented behavior
+ network = "tcp"
+ default:
+ return nil, UnknownNetworkError(network)
+ }
+ addrs, err := DefaultResolver.internetAddrList(context.Background(), network, address)
+ if err != nil {
+ return nil, err
+ }
+ return addrs.forResolve(network, address).(*TCPAddr), nil
+}
+
+// TCPAddrFromAddrPort returns addr as a TCPAddr. If addr.IsValid() is false,
+// then the returned TCPAddr will contain a nil IP field, indicating an
+// address family-agnostic unspecified address.
+func TCPAddrFromAddrPort(addr netip.AddrPort) *TCPAddr {
+ return &TCPAddr{
+ IP: addr.Addr().AsSlice(),
+ Zone: addr.Addr().Zone(),
+ Port: int(addr.Port()),
+ }
+}
+
+// TCPConn is an implementation of the Conn interface for TCP network
+// connections.
+type TCPConn struct {
+ conn
+}
+
+// SyscallConn returns a raw network connection.
+// This implements the syscall.Conn interface.
+func (c *TCPConn) SyscallConn() (syscall.RawConn, error) {
+ if !c.ok() {
+ return nil, syscall.EINVAL
+ }
+ return newRawConn(c.fd)
+}
+
+// ReadFrom implements the io.ReaderFrom ReadFrom method.
+func (c *TCPConn) ReadFrom(r io.Reader) (int64, error) {
+ if !c.ok() {
+ return 0, syscall.EINVAL
+ }
+ n, err := c.readFrom(r)
+ if err != nil && err != io.EOF {
+ err = &OpError{Op: "readfrom", Net: c.fd.net, Source: c.fd.laddr, Addr: c.fd.raddr, Err: err}
+ }
+ return n, 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 syscall.EINVAL
+ }
+ if err := c.fd.closeRead(); err != nil {
+ return &OpError{Op: "close", Net: c.fd.net, Source: c.fd.laddr, Addr: c.fd.raddr, Err: err}
+ }
+ return nil
+}
+
+// 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 syscall.EINVAL
+ }
+ if err := c.fd.closeWrite(); err != nil {
+ return &OpError{Op: "close", Net: c.fd.net, Source: c.fd.laddr, Addr: c.fd.raddr, Err: err}
+ }
+ return nil
+}
+
+// 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), the operating system finishes sending the
+// data in the background.
+//
+// If sec == 0, the operating system discards any unsent or
+// unacknowledged data.
+//
+// If sec > 0, the data is sent in the background as with sec < 0. On
+// some operating systems after sec seconds have elapsed any remaining
+// unsent data may be discarded.
+func (c *TCPConn) SetLinger(sec int) error {
+ if !c.ok() {
+ return syscall.EINVAL
+ }
+ if err := setLinger(c.fd, sec); err != nil {
+ return &OpError{Op: "set", Net: c.fd.net, Source: c.fd.laddr, Addr: c.fd.raddr, Err: err}
+ }
+ return nil
+}
+
+// SetKeepAlive sets whether the operating system should send
+// keep-alive messages on the connection.
+func (c *TCPConn) SetKeepAlive(keepalive bool) error {
+ if !c.ok() {
+ return syscall.EINVAL
+ }
+ if err := setKeepAlive(c.fd, keepalive); err != nil {
+ return &OpError{Op: "set", Net: c.fd.net, Source: c.fd.laddr, Addr: c.fd.raddr, Err: err}
+ }
+ return nil
+}
+
+// SetKeepAlivePeriod sets period between keep-alives.
+func (c *TCPConn) SetKeepAlivePeriod(d time.Duration) error {
+ if !c.ok() {
+ return syscall.EINVAL
+ }
+ if err := setKeepAlivePeriod(c.fd, d); err != nil {
+ return &OpError{Op: "set", Net: c.fd.net, Source: c.fd.laddr, Addr: c.fd.raddr, Err: err}
+ }
+ return nil
+}
+
+// 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 syscall.EINVAL
+ }
+ if err := setNoDelay(c.fd, noDelay); err != nil {
+ return &OpError{Op: "set", Net: c.fd.net, Source: c.fd.laddr, Addr: c.fd.raddr, Err: err}
+ }
+ return nil
+}
+
+func newTCPConn(fd *netFD, keepAlive time.Duration, keepAliveHook func(time.Duration)) *TCPConn {
+ setNoDelay(fd, true)
+ if keepAlive == 0 {
+ keepAlive = defaultTCPKeepAlive
+ }
+ if keepAlive > 0 {
+ setKeepAlive(fd, true)
+ setKeepAlivePeriod(fd, keepAlive)
+ if keepAliveHook != nil {
+ keepAliveHook(keepAlive)
+ }
+ }
+ return &TCPConn{conn{fd}}
+}
+
+// DialTCP acts like Dial for TCP networks.
+//
+// The network must be a TCP network name; see func Dial for details.
+//
+// If laddr is nil, a local address is automatically chosen.
+// If the IP field of raddr is nil or an unspecified IP address, the
+// local system is assumed.
+func DialTCP(network string, laddr, raddr *TCPAddr) (*TCPConn, error) {
+ switch network {
+ case "tcp", "tcp4", "tcp6":
+ default:
+ return nil, &OpError{Op: "dial", Net: network, Source: laddr.opAddr(), Addr: raddr.opAddr(), Err: UnknownNetworkError(network)}
+ }
+ if raddr == nil {
+ return nil, &OpError{Op: "dial", Net: network, Source: laddr.opAddr(), Addr: nil, Err: errMissingAddress}
+ }
+ sd := &sysDialer{network: network, address: raddr.String()}
+ c, err := sd.dialTCP(context.Background(), laddr, raddr)
+ if err != nil {
+ return nil, &OpError{Op: "dial", Net: network, Source: laddr.opAddr(), Addr: raddr.opAddr(), Err: err}
+ }
+ return c, nil
+}
+
+// TCPListener is a TCP network listener. Clients should typically
+// use variables of type Listener instead of assuming TCP.
+type TCPListener struct {
+ fd *netFD
+ lc ListenConfig
+}
+
+// SyscallConn returns a raw network connection.
+// This implements the syscall.Conn interface.
+//
+// The returned RawConn only supports calling Control. Read and
+// Write return an error.
+func (l *TCPListener) SyscallConn() (syscall.RawConn, error) {
+ if !l.ok() {
+ return nil, syscall.EINVAL
+ }
+ return newRawListener(l.fd)
+}
+
+// AcceptTCP accepts the next incoming call and returns the new
+// connection.
+func (l *TCPListener) AcceptTCP() (*TCPConn, error) {
+ if !l.ok() {
+ return nil, syscall.EINVAL
+ }
+ c, err := l.accept()
+ if err != nil {
+ return nil, &OpError{Op: "accept", Net: l.fd.net, Source: nil, Addr: l.fd.laddr, Err: err}
+ }
+ return c, 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() (Conn, error) {
+ if !l.ok() {
+ return nil, syscall.EINVAL
+ }
+ c, err := l.accept()
+ if err != nil {
+ return nil, &OpError{Op: "accept", Net: l.fd.net, Source: nil, Addr: l.fd.laddr, Err: err}
+ }
+ return c, nil
+}
+
+// Close stops listening on the TCP address.
+// Already Accepted connections are not closed.
+func (l *TCPListener) Close() error {
+ if !l.ok() {
+ return syscall.EINVAL
+ }
+ if err := l.close(); err != nil {
+ return &OpError{Op: "close", Net: l.fd.net, Source: nil, Addr: l.fd.laddr, Err: err}
+ }
+ return nil
+}
+
+// Addr returns the listener's network address, a *TCPAddr.
+// The Addr returned is shared by all invocations of Addr, so
+// do not modify it.
+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.ok() {
+ return syscall.EINVAL
+ }
+ if err := l.fd.pfd.SetDeadline(t); err != nil {
+ return &OpError{Op: "set", Net: l.fd.net, Source: nil, Addr: l.fd.laddr, Err: err}
+ }
+ return nil
+}
+
+// File returns a copy of the underlying os.File.
+// It is the caller's responsibility to close f when finished.
+// Closing l does not affect f, and closing f does not affect l.
+//
+// The returned os.File's file descriptor is different from the
+// connection's. Attempting to change properties of the original
+// using this duplicate may or may not have the desired effect.
+func (l *TCPListener) File() (f *os.File, err error) {
+ if !l.ok() {
+ return nil, syscall.EINVAL
+ }
+ f, err = l.file()
+ if err != nil {
+ return nil, &OpError{Op: "file", Net: l.fd.net, Source: nil, Addr: l.fd.laddr, Err: err}
+ }
+ return
+}
+
+// ListenTCP acts like Listen for TCP networks.
+//
+// The network must be a TCP network name; see func Dial for details.
+//
+// If the IP field of laddr is nil or an unspecified IP address,
+// ListenTCP listens on all available unicast and anycast IP addresses
+// of the local system.
+// If the Port field of laddr is 0, a port number is automatically
+// chosen.
+func ListenTCP(network string, laddr *TCPAddr) (*TCPListener, error) {
+ switch network {
+ case "tcp", "tcp4", "tcp6":
+ default:
+ return nil, &OpError{Op: "listen", Net: network, Source: nil, Addr: laddr.opAddr(), Err: UnknownNetworkError(network)}
+ }
+ if laddr == nil {
+ laddr = &TCPAddr{}
+ }
+ sl := &sysListener{network: network, address: laddr.String()}
+ ln, err := sl.listenTCP(context.Background(), laddr)
+ if err != nil {
+ return nil, &OpError{Op: "listen", Net: network, Source: nil, Addr: laddr.opAddr(), Err: err}
+ }
+ return ln, nil
+}
+
+// roundDurationUp rounds d to the next multiple of to.
+func roundDurationUp(d time.Duration, to time.Duration) time.Duration {
+ return (d + to - 1) / to
+}