Golang libcontainer.Process類代碼示例

// setup standard pipes so that the TTY of the calling runc process
// is not inherited by the container.
func createStdioPipes(p *libcontainer.Process, rootuid int) (*tty, error) {
	var (
		t   = &tty{}
		fds []int
	)
	r, w, err := os.Pipe()
	if err != nil {
		return nil, err
	}
	fds = append(fds, int(r.Fd()), int(w.Fd()))
	go io.Copy(w, os.Stdin)
	t.closers = append(t.closers, w)
	p.Stdin = r
	if r, w, err = os.Pipe(); err != nil {
		return nil, err
	}
	fds = append(fds, int(r.Fd()), int(w.Fd()))
	go io.Copy(os.Stdout, r)
	p.Stdout = w
	t.closers = append(t.closers, r)
	if r, w, err = os.Pipe(); err != nil {
		return nil, err
	}
	fds = append(fds, int(r.Fd()), int(w.Fd()))
	go io.Copy(os.Stderr, r)
	p.Stderr = w
	t.closers = append(t.closers, r)
	// change the ownership of the pipe fds incase we are in a user namespace.
	for _, fd := range fds {
		if err := syscall.Fchown(fd, rootuid, rootuid); err != nil {
			return nil, err
		}
	}
	return t, nil
}

// setup standard pipes so that the TTY of the calling runc process
// is not inherited by the container.
func createStdioPipes(p *libcontainer.Process, rootuid int) (*tty, error) {
	i, err := p.InitializeIO(rootuid)
	if err != nil {
		return nil, err
	}
	t := &tty{
		closers: []io.Closer{
			i.Stdin,
			i.Stdout,
			i.Stderr,
		},
	}
	// add the process's io to the post start closers if they support close
	for _, cc := range []interface{}{
		p.Stdin,
		p.Stdout,
		p.Stderr,
	} {
		if c, ok := cc.(io.Closer); ok {
			t.postStart = append(t.postStart, c)
		}
	}
	go func() {
		io.Copy(i.Stdin, os.Stdin)
		i.Stdin.Close()
	}()
	t.wg.Add(2)
	go t.copyIO(os.Stdout, i.Stdout)
	go t.copyIO(os.Stderr, i.Stderr)
	return t, nil
}

func createTty(p *libcontainer.Process, rootuid int, consolePath string) (*tty, error) {
	if consolePath != "" {
		if err := p.ConsoleFromPath(consolePath); err != nil {
			return nil, err
		}
		return &tty{}, nil
	}
	console, err := p.NewConsole(rootuid)
	if err != nil {
		return nil, err
	}
	go io.Copy(console, os.Stdin)
	go io.Copy(os.Stdout, console)

	state, err := term.SetRawTerminal(os.Stdin.Fd())
	if err != nil {
		return nil, fmt.Errorf("failed to set the terminal from the stdin: %v", err)
	}
	t := &tty{
		console: console,
		state:   state,
		closers: []io.Closer{
			console,
		},
	}
	return t, nil
}

func waitProcess(p *libcontainer.Process, t *testing.T) {
	_, file, line, _ := runtime.Caller(1)
	status, err := p.Wait()

	if err != nil {
		t.Fatalf("%s:%d: unexpected error: %s\n\n", filepath.Base(file), line, err.Error())
	}

	if !status.Success() {
		t.Fatalf("%s:%d: unexpected status: %s\n\n", filepath.Base(file), line, status.String())
	}
}

func createPidFile(path string, process *libcontainer.Process) error {
	pid, err := process.Pid()
	if err != nil {
		return err
	}
	f, err := os.Create(path)
	if err != nil {
		return err
	}
	defer f.Close()
	_, err = fmt.Fprintf(f, "%d", pid)
	return err
}

// we have to use this type of signal handler because there is a memory leak if we
// wait and reap with SICHLD.
func handleSignals(process *libcontainer.Process, tty *tty) {
	sigc := make(chan os.Signal, 10)
	signal.Notify(sigc)
	tty.resize()
	for sig := range sigc {
		switch sig {
		case syscall.SIGWINCH:
			tty.resize()
		default:
			process.Signal(sig)
		}
	}
}

func createPidFile(path string, process *libcontainer.Process) error {
	pid, err := process.Pid()
	if err != nil {
		return err
	}
	f, err := os.OpenFile(path, os.O_RDWR|os.O_CREATE|os.O_EXCL, 0666)
	if err != nil {
		return err
	}
	defer f.Close()
	_, err = fmt.Fprintf(f, "%d", pid)
	return err
}

func dupStdio(process *libcontainer.Process, rootuid int) error {
	process.Stdin = os.Stdin
	process.Stdout = os.Stdout
	process.Stderr = os.Stderr
	for _, fd := range []uintptr{
		os.Stdin.Fd(),
		os.Stdout.Fd(),
		os.Stderr.Fd(),
	} {
		if err := syscall.Fchown(int(fd), rootuid, rootuid); err != nil {
			return err
		}
	}
	return nil
}

// setup standard pipes so that the TTY of the calling runc process
// is not inherited by the container.
func createStdioPipes(p *libcontainer.Process, rootuid int) (*tty, error) {
	i, err := p.InitializeIO(rootuid)
	if err != nil {
		return nil, err
	}
	t := &tty{
		closers: []io.Closer{
			i.Stdin,
			i.Stdout,
			i.Stderr,
		},
	}
	go io.Copy(i.Stdin, os.Stdin)
	go io.Copy(os.Stdout, i.Stdout)
	go io.Copy(os.Stderr, i.Stderr)
	return t, nil
}

// createPidFile creates a file with the processes pid inside it atomically
// it creates a temp file with the paths filename + '.' infront of it
// then renames the file
func createPidFile(path string, process *libcontainer.Process) error {
	pid, err := process.Pid()
	if err != nil {
		return err
	}
	var (
		tmpDir  = filepath.Dir(path)
		tmpName = filepath.Join(tmpDir, fmt.Sprintf(".%s", filepath.Base(path)))
	)
	f, err := os.OpenFile(tmpName, os.O_RDWR|os.O_CREATE|os.O_EXCL|os.O_SYNC, 0666)
	if err != nil {
		return err
	}
	_, err = fmt.Fprintf(f, "%d", pid)
	f.Close()
	if err != nil {
		return err
	}
	return os.Rename(tmpName, path)
}

func waitInPIDHost(p *libcontainer.Process, c libcontainer.Container) func() (*os.ProcessState, error) {
	return func() (*os.ProcessState, error) {
		pid, err := p.Pid()
		if err != nil {
			return nil, err
		}

		process, err := os.FindProcess(pid)
		s, err := process.Wait()
		if err != nil {
			execErr, ok := err.(*exec.ExitError)
			if !ok {
				return s, err
			}
			s = execErr.ProcessState
		}
		killCgroupProcs(c)
		p.Wait()
		return s, err
	}
}

// forward handles the main signal event loop forwarding, resizing, or reaping depending
// on the signal received.
func (h *signalHandler) forward(process *libcontainer.Process) (int, error) {
	// make sure we know the pid of our main process so that we can return
	// after it dies.
	pid1, err := process.Pid()
	if err != nil {
		return -1, err
	}
	// perform the initial tty resize.
	h.tty.resize()
	for s := range h.signals {
		switch s {
		case syscall.SIGWINCH:
			h.tty.resize()
		case syscall.SIGCHLD:
			exits, err := h.reap()
			if err != nil {
				logrus.Error(err)
			}
			for _, e := range exits {
				logrus.WithFields(logrus.Fields{
					"pid":    e.pid,
					"status": e.status,
				}).Debug("process exited")
				if e.pid == pid1 {
					// call Wait() on the process even though we already have the exit
					// status because we must ensure that any of the go specific process
					// fun such as flushing pipes are complete before we return.
					process.Wait()
					return e.status, nil
				}
			}
		default:
			logrus.Debugf("sending signal to process %s", s)
			if err := syscall.Kill(pid1, s.(syscall.Signal)); err != nil {
				logrus.Error(err)
			}
		}
	}
	return -1, nil
}

func (t *tty) recvtty(process *libcontainer.Process, detach bool) error {
	console, err := process.GetConsole()
	if err != nil {
		return err
	}

	if !detach {
		go io.Copy(console, os.Stdin)
		t.wg.Add(1)
		go t.copyIO(os.Stdout, console)

		state, err := term.SetRawTerminal(os.Stdin.Fd())
		if err != nil {
			return fmt.Errorf("failed to set the terminal from the stdin: %v", err)
		}
		t.state = state
	}

	t.console = console
	t.closers = []io.Closer{console}
	return nil
}

// setupIO modifies the given process config according to the options.
func setupIO(process *libcontainer.Process, rootuid, rootgid int, createTTY, detach bool) (*tty, error) {
	// This is entirely handled by recvtty.
	if createTTY {
		process.Stdin = nil
		process.Stdout = nil
		process.Stderr = nil
		return &tty{}, nil
	}

	// When we detach, we just dup over stdio and call it a day. There's no
	// requirement that we set up anything nice for our caller or the
	// container.
	if detach {
		if err := dupStdio(process, rootuid, rootgid); err != nil {
			return nil, err
		}
		return &tty{}, nil
	}

	// XXX: This doesn't sit right with me. It's ugly.
	return createStdioPipes(process, rootuid, rootgid)
}

func createTty(p *libcontainer.Process, rootuid int) (*tty, error) {
	console, err := p.NewConsole(rootuid)
	if err != nil {
		return nil, err
	}
	go io.Copy(console, os.Stdin)
	go io.Copy(os.Stdout, console)
	state, err := term.SetRawTerminal(os.Stdin.Fd())
	if err != nil {
		return nil, err
	}
	t := &tty{
		console: console,
		state:   state,
		closers: []io.Closer{
			console,
		},
	}
	p.Stderr = nil
	p.Stdout = nil
	p.Stdin = nil
	return t, nil
}