Golang Process.Pid方法代码示例

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
}

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
}

// 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 TestEnter(t *testing.T) {
	if testing.Short() {
		return
	}
	root, err := newTestRoot()
	ok(t, err)
	defer os.RemoveAll(root)

	rootfs, err := newRootfs()
	ok(t, err)
	defer remove(rootfs)

	config := newTemplateConfig(rootfs)

	container, err := factory.Create("test", config)
	ok(t, err)
	defer container.Destroy()

	// Execute a first process in the container
	stdinR, stdinW, err := os.Pipe()
	ok(t, err)

	var stdout, stdout2 bytes.Buffer

	pconfig := libcontainer.Process{
		Args:   []string{"sh", "-c", "cat && readlink /proc/self/ns/pid"},
		Env:    standardEnvironment,
		Stdin:  stdinR,
		Stdout: &stdout,
	}
	err = container.Start(&pconfig)
	stdinR.Close()
	defer stdinW.Close()
	ok(t, err)
	pid, err := pconfig.Pid()
	ok(t, err)

	// Execute another process in the container
	stdinR2, stdinW2, err := os.Pipe()
	ok(t, err)
	pconfig2 := libcontainer.Process{
		Env: standardEnvironment,
	}
	pconfig2.Args = []string{"sh", "-c", "cat && readlink /proc/self/ns/pid"}
	pconfig2.Stdin = stdinR2
	pconfig2.Stdout = &stdout2

	err = container.Start(&pconfig2)
	stdinR2.Close()
	defer stdinW2.Close()
	ok(t, err)

	pid2, err := pconfig2.Pid()
	ok(t, err)

	processes, err := container.Processes()
	ok(t, err)

	n := 0
	for i := range processes {
		if processes[i] == pid || processes[i] == pid2 {
			n++
		}
	}
	if n != 2 {
		t.Fatal("unexpected number of processes", processes, pid, pid2)
	}

	// Wait processes
	stdinW2.Close()
	waitProcess(&pconfig2, t)

	stdinW.Close()
	waitProcess(&pconfig, t)

	// Check that both processes live in the same pidns
	pidns := string(stdout.Bytes())
	ok(t, err)

	pidns2 := string(stdout2.Bytes())
	ok(t, err)

	if pidns != pidns2 {
		t.Fatal("The second process isn't in the required pid namespace", pidns, pidns2)
	}
}

func TestCheckpoint(t *testing.T) {
	if testing.Short() {
		return
	}
	root, err := newTestRoot()
	if err != nil {
		t.Fatal(err)
	}
	defer os.RemoveAll(root)

	rootfs, err := newRootfs()
	if err != nil {
		t.Fatal(err)
	}
	defer remove(rootfs)

	config := newTemplateConfig(rootfs)

	config.Mounts = append(config.Mounts, &configs.Mount{
		Destination: "/sys/fs/cgroup",
		Device:      "cgroup",
		Flags:       defaultMountFlags | syscall.MS_RDONLY,
	})

	factory, err := libcontainer.New(root, libcontainer.Cgroupfs)

	if err != nil {
		t.Fatal(err)
	}

	container, err := factory.Create("test", config)
	if err != nil {
		t.Fatal(err)
	}
	defer container.Destroy()

	stdinR, stdinW, err := os.Pipe()
	if err != nil {
		t.Fatal(err)
	}

	var stdout bytes.Buffer

	pconfig := libcontainer.Process{
		Cwd:    "/",
		Args:   []string{"cat"},
		Env:    standardEnvironment,
		Stdin:  stdinR,
		Stdout: &stdout,
	}

	err = container.Start(&pconfig)
	stdinR.Close()
	defer stdinW.Close()
	if err != nil {
		t.Fatal(err)
	}

	pid, err := pconfig.Pid()
	if err != nil {
		t.Fatal(err)
	}

	process, err := os.FindProcess(pid)
	if err != nil {
		t.Fatal(err)
	}

	imagesDir, err := ioutil.TempDir("", "criu")
	if err != nil {
		t.Fatal(err)
	}
	defer os.RemoveAll(imagesDir)

	checkpointOpts := &libcontainer.CriuOpts{
		ImagesDirectory: imagesDir,
		WorkDirectory:   imagesDir,
	}
	dumpLog := filepath.Join(checkpointOpts.WorkDirectory, "dump.log")
	restoreLog := filepath.Join(checkpointOpts.WorkDirectory, "restore.log")

	if err := container.Checkpoint(checkpointOpts); err != nil {
		showFile(t, dumpLog)
		t.Fatal(err)
	}

	state, err := container.Status()
	if err != nil {
		t.Fatal(err)
	}

	if state != libcontainer.Running {
		t.Fatal("Unexpected state checkpoint: ", state)
	}

	stdinW.Close()
	_, err = process.Wait()
	if err != nil {
		t.Fatal(err)
	}
//.........这里部分代码省略.........

func TestCheckpoint(t *testing.T) {
	if testing.Short() {
		return
	}
	root, err := newTestRoot()
	if err != nil {
		t.Fatal(err)
	}
	defer os.RemoveAll(root)

	rootfs, err := newRootfs()
	if err != nil {
		t.Fatal(err)
	}
	defer remove(rootfs)

	config := newTemplateConfig(rootfs)

	factory, err := libcontainer.New(root, libcontainer.Cgroupfs)

	if err != nil {
		t.Fatal(err)
	}

	container, err := factory.Create("test", config)
	if err != nil {
		t.Fatal(err)
	}
	defer container.Destroy()

	stdinR, stdinW, err := os.Pipe()
	if err != nil {
		t.Fatal(err)
	}

	var stdout bytes.Buffer

	pconfig := libcontainer.Process{
		Args:   []string{"cat"},
		Env:    standardEnvironment,
		Stdin:  stdinR,
		Stdout: &stdout,
	}

	err = container.Start(&pconfig)
	stdinR.Close()
	defer stdinW.Close()
	if err != nil {
		t.Fatal(err)
	}

	pid, err := pconfig.Pid()
	if err != nil {
		t.Fatal(err)
	}

	process, err := os.FindProcess(pid)
	if err != nil {
		t.Fatal(err)
	}

	imagesDir, err := ioutil.TempDir("", "criu")
	if err != nil {
		t.Fatal(err)
	}
	defer os.RemoveAll(imagesDir)

	checkpointOpts := &libcontainer.CriuOpts{
		ImagesDirectory: imagesDir,
		WorkDirectory:   imagesDir,
	}

	if err := container.Checkpoint(checkpointOpts); err != nil {
		t.Fatal(err)
	}

	state, err := container.Status()
	if err != nil {
		t.Fatal(err)
	}

	if state != libcontainer.Checkpointed {
		t.Fatal("Unexpected state: ", state)
	}

	stdinW.Close()
	_, err = process.Wait()
	if err != nil {
		t.Fatal(err)
	}

	// reload the container
	container, err = factory.Load("test")
	if err != nil {
		t.Fatal(err)
	}

	restoreStdinR, restoreStdinW, err := os.Pipe()
	if err != nil {
		t.Fatal(err)
//.........这里部分代码省略.........