Golang syscall.UnixRights函数代码示例

func SendRequest(c *net.UnixConn, req *server.Request) error {
	payload, err := json.Marshal(req)
	if err != nil {
		return err
	}
	err = binary.Write(c, binary.BigEndian, uint32(len(payload)))
	if err != nil {
		return err
	}
	n, err := c.Write(payload)
	if err != nil {
		return err
	} else if n != len(payload) {
		return fmt.Errorf("Failed to write full payload, expected %v, wrote %v", len(payload), n)
	}

	if !req.HasFds {
		return nil
	}
	// Send filedescriptors with a 1 byte message.
	var oob []byte
	oob = syscall.UnixRights(req.Fds...)
	payload = make([]byte, 1)
	n, oobn, err := c.WriteMsgUnix(payload, oob, nil)
	if err != nil {
		return err
	} else if n != len(payload) || oobn != len(oob) {
		return fmt.Errorf("Error writing to socket, expected n=%v got %v, oob=%v got %v", len(payload), n, len(oob), oobn)
	}
	return nil
}

func writeData(conn *net.UnixConn, files []*os.File, pid int, responseErr error) {
	var errMsg string = ""
	if responseErr != nil {
		errMsg = responseErr.Error()
	}
	response := &Response{
		Pid:        pid,
		ErrMessage: errMsg,
	}

	responseJson, _ := json.Marshal(response) // Ignore error

	args := make([]int, len(files))
	for i, f := range files {
		args[i] = int(f.Fd())
	}
	resp := syscall.UnixRights(args...)

	conn.WriteMsgUnix(responseJson, resp, nil) // Ignore error

	// Close the files whose descriptors have been sent to the host to ensure that
	// a close on the host takes effect in a timely fashion.
	for _, file := range files {
		file.Close() // Ignore error
	}
}

func (t *unixTransport) SendMessage(msg *Message) error {
	fds := make([]int, 0)
	for i, v := range msg.Body {
		if fd, ok := v.(UnixFD); ok {
			msg.Body[i] = UnixFDIndex(len(fds))
			fds = append(fds, int(fd))
		}
	}
	if len(fds) != 0 {
		if !t.hasUnixFDs {
			return errors.New("dbus: unix fd passing not enabled")
		}
		msg.Headers[FieldUnixFDs] = MakeVariant(uint32(len(fds)))
		oob := syscall.UnixRights(fds...)
		buf := new(bytes.Buffer)
		msg.EncodeTo(buf, binary.LittleEndian)
		n, oobn, err := t.UnixConn.WriteMsgUnix(buf.Bytes(), oob, nil)
		if err != nil {
			return err
		}
		if n != buf.Len() || oobn != len(oob) {
			return io.ErrShortWrite
		}
	} else {
		if err := msg.EncodeTo(t, binary.LittleEndian); err != nil {
			return nil
		}
	}
	return nil
}

func Notify(state string, fds ...int) {
	ns := os.Getenv("NOTIFY_SOCKET")
	if ns == "" {
		return
	}

	addr := &net.UnixAddr{
		Name: ns,
		Net:  "unixgram",
	}

	conn, err := net.DialUnix("unixgram", nil, addr)
	if err != nil {
		return
	}

	defer conn.Close()

	if len(fds) > 0 {
		rights := syscall.UnixRights(fds...)

		conn.WriteMsgUnix([]byte(state), rights, nil)

	} else {
		conn.Write([]byte(state))
	}
}

func (m *Message) Write(arg interface{}) error {
	switch t := arg.(type) {
	case Proxy:
		return binary.Write(m.data, binary.LittleEndian, uint32(t.Id()))
	case uint32, int32:
		return binary.Write(m.data, binary.LittleEndian, t)
	case float32:
		f := float64ToFixed(float64(t))
		return binary.Write(m.data, binary.LittleEndian, f)
	case string:
		str, _ := arg.(string)
		tail := 4 - (len(str) & 0x3)
		err := binary.Write(m.data, binary.LittleEndian, uint32(len(str)+tail))
		if err != nil {
			return err
		}
		err = binary.Write(m.data, binary.LittleEndian, []byte(str))
		if err != nil {
			return err
		}
		padding := make([]byte, tail)
		return binary.Write(m.data, binary.LittleEndian, padding)
	case uintptr:
		rights := syscall.UnixRights(int(t))
		return binary.Write(m.control, binary.LittleEndian, rights)
	default:
		panic("Invalid Wayland request parameter type.")
	}
	return nil
}

func (w *FDWriter) Write(b []byte) (int, error) {
	if len(w.fds) == 0 {
		return w.conn.Write(b)
	} else {
		rights := syscall.UnixRights(w.fds...)
		n, _, err := w.conn.WriteMsgUnix(b, rights, nil)
		w.fds = nil
		return n, err
	}
}

func WriteFile(c *net.UnixConn, file *os.File, timeout time.Duration) error {
	if timeout > 0 {
		deadline := time.Now().Add(timeout)
		if err := c.SetWriteDeadline(deadline); err != nil {
			return err
		}
	}
	oob := syscall.UnixRights(int(file.Fd()))
	_, _, err := c.WriteMsgUnix(nil, oob, nil)
	return err
}

func (fd Fd) writeTo(c *net.UnixConn) error {
	var b []byte
	oob := syscall.UnixRights(int(fd))
	_, oobn, err := c.WriteMsgUnix(b, oob, nil)
	if err != nil {
		return err
	}
	if oobn != len(oob) {
		return fmt.Errorf("expected to write %d oob bytes, wrote %d", len(oob), oobn)
	}
	return nil
}

func (usock *Usock) WriteFD(fd int) error {
	rights := syscall.UnixRights(fd)

	dummyByte := []byte("\000")
	n, oobn, err := usock.Conn.WriteMsgUnix(dummyByte, rights, nil)
	if err != nil {
		str := fmt.Sprintf("Usock#WriteFD:WriteMsgUnix: %v %v\n", err, syscall.EINVAL)
		return errors.New(str)
	}
	if n != 1 || oobn != len(rights) {
		str := fmt.Sprintf("Usock#WriteFD:WriteMsgUnix = %d, %d; want 1, %d\n", n, oobn, len(rights))
		return errors.New(str)
	}
	return nil
}

func (s *OOBUnixConn) Write(buf []byte) (int, error) {
	var oob []byte
	s.m.Lock()
	fds := s.sendFDs
	s.sendFDs = nil
	s.m.Unlock()
	if len(fds) > 0 {
		oob = syscall.UnixRights(fds...)
	}
	n, oobn, err := s.WriteMsgUnix(buf, oob, nil)
	if err == nil && oobn != len(oob) {
		err = ErrOOBSendFailed
	}
	return n, err
}

func SendFd(conn *net.UnixConn, file *os.File) error {
	rights := syscall.UnixRights(int(file.Fd()))
	dummy := []byte("x")
	n, oobn, err := conn.WriteMsgUnix(dummy, rights, nil)
	if err != nil {
		return fmt.Errorf("sendfd: err %v", err)
	}
	if n != len(dummy) {
		return fmt.Errorf("sendfd: short write %v", conn)
	}
	if oobn != len(rights) {
		return fmt.Errorf("sendfd: short oob write %v", conn)
	}
	return nil
}

func writeData(conn *net.UnixConn, response *container_daemon.ResponseMessage) {
	data, _ := json.Marshal(response) // Ignore error

	args := make([]int, len(response.Files))
	for i, f := range response.Files {
		args[i] = int(f.Fd())
	}
	oobData := syscall.UnixRights(args...)

	conn.WriteMsgUnix(data, oobData, nil) // Ignore error

	// Close the files whose descriptors have been sent to the host to ensure that
	// a close on the host takes effect in a timely fashion.
	for _, file := range response.Files {
		file.Close() // Ignore error
	}
}

// passFDChild is the child process used by TestPassFD.
func passFDChild() {
	defer os.Exit(0)

	// Look for our fd. It should be fd 3, but we work around an fd leak
	// bug here (http://golang.org/issue/2603) to let it be elsewhere.
	var uc *net.UnixConn
	for fd := uintptr(3); fd <= 10; fd++ {
		f := os.NewFile(fd, "unix-conn")
		var ok bool
		netc, _ := net.FileConn(f)
		uc, ok = netc.(*net.UnixConn)
		if ok {
			break
		}
	}
	if uc == nil {
		fmt.Println("failed to find unix fd")
		return
	}

	// Make a file f to send to our parent process on uc.
	// We make it in tempDir, which our parent will clean up.
	flag.Parse()
	tempDir := flag.Arg(0)
	f, err := ioutil.TempFile(tempDir, "")
	if err != nil {
		fmt.Printf("TempFile: %v", err)
		return
	}

	f.Write([]byte("Hello from child process!\n"))
	f.Seek(0, 0)

	rights := syscall.UnixRights(int(f.Fd()))
	dummyByte := []byte("x")
	n, oobn, err := uc.WriteMsgUnix(dummyByte, rights, nil)
	if err != nil {
		fmt.Printf("WriteMsgUnix: %v", err)
		return
	}
	if n != 1 || oobn != len(rights) {
		fmt.Printf("WriteMsgUnix = %d, %d; want 1, %d", n, oobn, len(rights))
		return
	}
}

func (u *Usock) WriteFD(fd int) error {
	u.Lock()
	defer u.Unlock()

	rights := syscall.UnixRights(fd)

	dummyByte := []byte{0}
	n, oobn, err := u.reader.Conn.WriteMsgUnix(dummyByte, rights, nil)
	if err != nil {
		str := fmt.Sprintf("Usock#WriteFD:WriteMsgUnix: %v / %v\n", err, syscall.EINVAL)
		return errors.New(str)
	}
	if n != 1 || oobn != len(rights) {
		str := fmt.Sprintf("Usock#WriteFD:WriteMsgUnix = %d, %d; want 1, %d\n", n, oobn, len(rights))
		return errors.New(str)
	}
	return nil
}

func (c *Conn) WriteMessage(m *Message) (err error) {
	var payload []byte
	if m.p != nil {
		payload = m.p.Bytes()
	}
	if err = c.writeHeader(m.object, m.opcode, uint16(len(payload))); err != nil {
		return
	}
	if len(payload) == 0 {
		// message without payload wouldn't contain fds, so we can return here
		return nil
	}
	var oob []byte
	if len(m.fds) != 0 {
		oob = syscall.UnixRights(m.fds...)
	}
	_, _, err = c.c.WriteMsgUnix(payload, oob, nil)
	return
}