Golang namespaces.Exec函数代码示例

// start a long-running container so we have time to inspect execin processes
func startLongRunningContainer(config *libcontainer.Config) (*exec.Cmd, string, chan error) {
	containerErr := make(chan error, 1)
	containerCmd := &exec.Cmd{}
	var statePath string

	createCmd := func(container *libcontainer.Config, console, dataPath, init string,
		pipe *os.File, args []string) *exec.Cmd {
		containerCmd = namespaces.DefaultCreateCommand(container, console, dataPath, init, pipe, args)
		statePath = dataPath
		return containerCmd
	}

	var containerStart sync.WaitGroup
	containerStart.Add(1)
	go func() {
		buffers := newStdBuffers()
		_, err := namespaces.Exec(config,
			buffers.Stdin, buffers.Stdout, buffers.Stderr,
			"", config.RootFs, []string{"sleep", "10"},
			createCmd, containerStart.Done)
		containerErr <- err
	}()
	containerStart.Wait()

	return containerCmd, statePath, containerErr
}

// startContainer starts the container. Returns the exit status or -1 and an
// error.
//
// Signals sent to the current process will be forwarded to container.
func startContainer(container *libcontainer.Config, term namespaces.Terminal, dataPath string, args []string) (int, error) {
	var (
		cmd  *exec.Cmd
		sigc = make(chan os.Signal, 10)
	)

	signal.Notify(sigc)

	createCommand := func(container *libcontainer.Config, console, rootfs, dataPath, init string, pipe *os.File, args []string) *exec.Cmd {
		cmd = namespaces.DefaultCreateCommand(container, console, rootfs, dataPath, init, pipe, args)
		if logPath != "" {
			cmd.Env = append(cmd.Env, fmt.Sprintf("log=%s", logPath))
		}
		return cmd
	}

	startCallback := func() {
		go func() {
			for sig := range sigc {
				cmd.Process.Signal(sig)
			}
		}()
	}

	return namespaces.Exec(container, term, "", dataPath, args, createCommand, startCallback)
}

func (d *driver) Run(c *execdriver.Command, pipes *execdriver.Pipes, startCallback execdriver.StartCallback) (int, error) {
	// take the Command and populate the libcontainer.Config from it
	container, err := d.createContainer(c)
	if err != nil {
		return -1, err
	}
	d.Lock()
	d.activeContainers[c.ID] = &activeContainer{
		container: container,
		cmd:       &c.Cmd,
	}
	d.Unlock()

	var (
		dataPath = filepath.Join(d.root, c.ID)
		args     = append([]string{c.Entrypoint}, c.Arguments...)
	)
	if err := d.createContainerRoot(c.ID); err != nil {
		return -1, err
	}
	defer d.removeContainerRoot(c.ID)

	if err := d.writeContainerFile(container, c.ID); err != nil {
		return -1, err
	}

	term := getTerminal(c, pipes)

	return namespaces.Exec(container, term, c.Rootfs, dataPath, args, func(container *libcontainer.Config, console, rootfs, dataPath, init string, child *os.File, args []string) *exec.Cmd {
		// we need to join the rootfs because namespaces will setup the rootfs and chroot
		initPath := filepath.Join(c.Rootfs, c.InitPath)

		c.Path = d.initPath
		c.Args = append([]string{
			initPath,
			"-driver", DriverName,
			"-console", console,
			"-pipe", "3",
			"-root", filepath.Join(d.root, c.ID),
			"--",
		}, args...)

		// set this to nil so that when we set the clone flags anything else is reset
		c.SysProcAttr = nil
		system.SetCloneFlags(&c.Cmd, uintptr(namespaces.GetNamespaceFlags(container.Namespaces)))
		c.ExtraFiles = []*os.File{child}

		c.Env = container.Env
		c.Dir = c.Rootfs

		return &c.Cmd
	}, func() {
		if startCallback != nil {
			c.ContainerPid = c.Process.Pid
			startCallback(c)
		}
	})
}

// runContainer runs the container with the specific config and arguments
//
// buffers are returned containing the STDOUT and STDERR output for the run
// along with the exit code and any go error
func runContainer(config *libcontainer.Config, console string, args ...string) (buffers *stdBuffers, exitCode int, err error) {
	if err := writeConfig(config); err != nil {
		return nil, -1, err
	}

	buffers = newStdBuffers()
	exitCode, err = namespaces.Exec(config, buffers.Stdin, buffers.Stdout, buffers.Stderr,
		console, config.RootFs, args, namespaces.DefaultCreateCommand, nil)
	return
}

// startContainer starts the container. Returns the exit status or -1 and an
// error.
//
// Signals sent to the current process will be forwarded to container.
func startContainer(container *libcontainer.Config, dataPath string, args []string) (int, error) {
	var (
		cmd  *exec.Cmd
		sigc = make(chan os.Signal, 10)
	)

	signal.Notify(sigc)

	createCommand := func(container *libcontainer.Config, console, rootfs, dataPath, init string, pipe *os.File, args []string) *exec.Cmd {
		cmd = namespaces.DefaultCreateCommand(container, console, rootfs, dataPath, init, pipe, args)
		if logPath != "" {
			cmd.Env = append(cmd.Env, fmt.Sprintf("log=%s", logPath))
		}
		return cmd
	}

	var (
		master  *os.File
		console string
		err     error

		stdin  = os.Stdin
		stdout = os.Stdout
		stderr = os.Stderr
	)

	if container.Tty {
		stdin = nil
		stdout = nil
		stderr = nil

		master, console, err = consolepkg.CreateMasterAndConsole()
		if err != nil {
			return -1, err
		}

		go io.Copy(master, os.Stdin)
		go io.Copy(os.Stdout, master)

		state, err := term.SetRawTerminal(os.Stdin.Fd())
		if err != nil {
			return -1, err
		}

		defer term.RestoreTerminal(os.Stdin.Fd(), state)
	}

	startCallback := func() {
		go func() {
			resizeTty(master)

			for sig := range sigc {
				switch sig {
				case syscall.SIGWINCH:
					resizeTty(master)
				default:
					cmd.Process.Signal(sig)
				}
			}
		}()
	}

	return namespaces.Exec(container, stdin, stdout, stderr, console, "", dataPath, args, createCommand, startCallback)
}

func (d *driver) Run(c *execdriver.Command, pipes *execdriver.Pipes, startCallback execdriver.StartCallback) (int, error) {
	// take the Command and populate the libcontainer.Config from it
	container, err := d.createContainer(c)
	if err != nil {
		return -1, err
	}

	var term execdriver.Terminal

	if c.ProcessConfig.Tty {
		term, err = NewTtyConsole(&c.ProcessConfig, pipes)
	} else {
		term, err = execdriver.NewStdConsole(&c.ProcessConfig, pipes)
	}
	if err != nil {
		return -1, err
	}
	c.ProcessConfig.Terminal = term

	d.Lock()
	d.activeContainers[c.ID] = &activeContainer{
		container: container,
		cmd:       &c.ProcessConfig.Cmd,
	}
	d.Unlock()

	var (
		dataPath = filepath.Join(d.root, c.ID)
		args     = append([]string{c.ProcessConfig.Entrypoint}, c.ProcessConfig.Arguments...)
	)

	if err := d.createContainerRoot(c.ID); err != nil {
		return -1, err
	}
	defer d.removeContainerRoot(c.ID)

	if err := d.writeContainerFile(container, c.ID); err != nil {
		return -1, err
	}

	return namespaces.Exec(container, c.ProcessConfig.Stdin, c.ProcessConfig.Stdout, c.ProcessConfig.Stderr, c.ProcessConfig.Console, c.Rootfs, dataPath, args, func(container *libcontainer.Config, console, rootfs, dataPath, init string, child *os.File, args []string) *exec.Cmd {
		c.ProcessConfig.Path = d.initPath
		c.ProcessConfig.Args = append([]string{
			DriverName,
			"-console", console,
			"-pipe", "3",
			"-root", filepath.Join(d.root, c.ID),
			"--",
		}, args...)

		// set this to nil so that when we set the clone flags anything else is reset
		c.ProcessConfig.SysProcAttr = &syscall.SysProcAttr{
			Cloneflags: uintptr(namespaces.GetNamespaceFlags(container.Namespaces)),
		}
		c.ProcessConfig.ExtraFiles = []*os.File{child}

		c.ProcessConfig.Env = container.Env
		c.ProcessConfig.Dir = c.Rootfs

		return &c.ProcessConfig.Cmd
	}, func() {
		if startCallback != nil {
			c.ContainerPid = c.ProcessConfig.Process.Pid
			startCallback(&c.ProcessConfig, c.ContainerPid)
		}
	})
}

func (d *driver) Run(c *execdriver.Command, pipes *execdriver.Pipes, startCallback execdriver.StartCallback) (execdriver.ExitStatus, error) {
	// take the Command and populate the libcontainer.Config from it
	container, err := d.createContainer(c)
	if err != nil {
		return execdriver.ExitStatus{ExitCode: -1}, err
	}

	var term execdriver.Terminal

	if c.ProcessConfig.Tty {
		term, err = NewTtyConsole(&c.ProcessConfig, pipes)
	} else {
		term, err = execdriver.NewStdConsole(&c.ProcessConfig, pipes)
	}
	if err != nil {
		return execdriver.ExitStatus{ExitCode: -1}, err
	}
	c.ProcessConfig.Terminal = term

	d.Lock()
	d.activeContainers[c.ID] = &activeContainer{
		container: container,
		cmd:       &c.ProcessConfig.Cmd,
	}
	d.Unlock()

	var (
		dataPath = filepath.Join(d.root, c.ID)
		args     = append([]string{c.ProcessConfig.Entrypoint}, c.ProcessConfig.Arguments...)
	)

	if err := d.createContainerRoot(c.ID); err != nil {
		return execdriver.ExitStatus{ExitCode: -1}, err
	}
	defer d.cleanContainer(c.ID)

	if err := d.writeContainerFile(container, c.ID); err != nil {
		return execdriver.ExitStatus{ExitCode: -1}, err
	}

	execOutputChan := make(chan execOutput, 1)
	waitForStart := make(chan struct{})

	go func() {
		exitCode, err := namespaces.Exec(container, c.ProcessConfig.Stdin, c.ProcessConfig.Stdout, c.ProcessConfig.Stderr, c.ProcessConfig.Console, dataPath, args, func(container *libcontainer.Config, console, dataPath, init string, child *os.File, args []string) *exec.Cmd {
			c.ProcessConfig.Path = d.initPath
			c.ProcessConfig.Args = append([]string{
				DriverName,
				"-console", console,
				"-pipe", "3",
				"-root", filepath.Join(d.root, c.ID),
				"--",
			}, args...)

			// set this to nil so that when we set the clone flags anything else is reset
			c.ProcessConfig.SysProcAttr = &syscall.SysProcAttr{
				Cloneflags: uintptr(namespaces.GetNamespaceFlags(container.Namespaces)),
			}
			c.ProcessConfig.ExtraFiles = []*os.File{child}

			c.ProcessConfig.Env = container.Env
			c.ProcessConfig.Dir = container.RootFs

			return &c.ProcessConfig.Cmd
		}, func() {
			close(waitForStart)
			if startCallback != nil {
				c.ContainerPid = c.ProcessConfig.Process.Pid
				startCallback(&c.ProcessConfig, c.ContainerPid)
			}
		})
		execOutputChan <- execOutput{exitCode, err}
	}()

	select {
	case execOutput := <-execOutputChan:
		return execdriver.ExitStatus{ExitCode: execOutput.exitCode}, execOutput.err
	case <-waitForStart:
		break
	}

	oomKill := false
	state, err := libcontainer.GetState(filepath.Join(d.root, c.ID))
	if err == nil {
		oomKillNotification, err := libcontainer.NotifyOnOOM(state)
		if err == nil {
			_, oomKill = <-oomKillNotification
		} else {
			log.Warnf("WARNING: Your kernel does not support OOM notifications: %s", err)
		}
	} else {
		log.Warnf("Failed to get container state, oom notify will not work: %s", err)
	}
	// wait for the container to exit.
	execOutput := <-execOutputChan

	return execdriver.ExitStatus{ExitCode: execOutput.exitCode, OOMKilled: oomKill}, execOutput.err
}