Golang Container.Lock方法代码示例

// Update the container's Status.Health struct based on the latest probe's result.
func handleProbeResult(d *Daemon, c *container.Container, result *types.HealthcheckResult) {
	c.Lock()
	defer c.Unlock()

	retries := c.Config.Healthcheck.Retries
	if retries <= 0 {
		retries = defaultProbeRetries
	}

	h := c.State.Health
	oldStatus := h.Status

	if len(h.Log) >= maxLogEntries {
		h.Log = append(h.Log[len(h.Log)+1-maxLogEntries:], result)
	} else {
		h.Log = append(h.Log, result)
	}

	if result.ExitCode == exitStatusHealthy {
		h.FailingStreak = 0
		h.Status = types.Healthy
	} else {
		// Failure (including invalid exit code)
		h.FailingStreak++
		if h.FailingStreak >= retries {
			h.Status = types.Unhealthy
		}
		// Else we're starting or healthy. Stay in that state.
	}

	if oldStatus != h.Status {
		d.LogContainerEvent(c, "health_status: "+h.Status)
	}
}

func (daemon *Daemon) setHostConfig(container *container.Container, hostConfig *runconfig.HostConfig) error {
	container.Lock()
	if err := parseSecurityOpt(container, hostConfig); err != nil {
		container.Unlock()
		return err
	}
	container.Unlock()

	// Do not lock while creating volumes since this could be calling out to external plugins
	// Don't want to block other actions, like `docker ps` because we're waiting on an external plugin
	if err := daemon.registerMountPoints(container, hostConfig); err != nil {
		return err
	}

	container.Lock()
	defer container.Unlock()

	// Register any links from the host config before starting the container
	if err := daemon.registerLinks(container, hostConfig); err != nil {
		return err
	}

	container.HostConfig = hostConfig
	container.ToDisk()
	return nil
}

// containerPause pauses the container execution without stopping the process.
// The execution can be resumed by calling containerUnpause.
func (daemon *Daemon) containerPause(container *container.Container) error {
	container.Lock()
	defer container.Unlock()

	// We cannot Pause the container which is not running
	if !container.Running {
		return derr.ErrorCodeNotRunning.WithArgs(container.ID)
	}

	// We cannot Pause the container which is already paused
	if container.Paused {
		return derr.ErrorCodeAlreadyPaused.WithArgs(container.ID)
	}

	// We cannot Pause the container which is restarting
	if container.Restarting {
		return derr.ErrorCodeContainerRestarting.WithArgs(container.ID)
	}

	if err := daemon.execDriver.Pause(container.Command); err != nil {
		return derr.ErrorCodeCantPause.WithArgs(container.ID, err)
	}
	container.Paused = true
	daemon.LogContainerEvent(container, "pause")
	return nil
}

// killWithSignal sends the container the given signal. This wrapper for the
// host specific kill command prepares the container before attempting
// to send the signal. An error is returned if the container is paused
// or not running, or if there is a problem returned from the
// underlying kill command.
func (daemon *Daemon) killWithSignal(container *container.Container, sig int) error {
	logrus.Debugf("Sending %d to %s", sig, container.ID)
	container.Lock()
	defer container.Unlock()

	// We could unpause the container for them rather than returning this error
	if container.Paused {
		return derr.ErrorCodeUnpauseContainer.WithArgs(container.ID)
	}

	if !container.Running {
		return derr.ErrorCodeNotRunning.WithArgs(container.ID)
	}

	container.ExitOnNext()

	// if the container is currently restarting we do not need to send the signal
	// to the process.  Telling the monitor that it should exit on it's next event
	// loop is enough
	if container.Restarting {
		return nil
	}

	if err := daemon.kill(container, sig); err != nil {
		return err
	}

	attributes := map[string]string{
		"signal": fmt.Sprintf("%d", sig),
	}
	daemon.LogContainerEventWithAttributes(container, "kill", attributes)
	return nil
}

// containerPause pauses the container execution without stopping the process.
// The execution can be resumed by calling containerUnpause.
func (daemon *Daemon) containerPause(container *container.Container) error {
	container.Lock()
	defer container.Unlock()

	// We cannot Pause the container which is not running
	if !container.Running {
		return errNotRunning{container.ID}
	}

	// We cannot Pause the container which is already paused
	if container.Paused {
		return fmt.Errorf("Container %s is already paused", container.ID)
	}

	// We cannot Pause the container which is restarting
	if container.Restarting {
		return errContainerIsRestarting(container.ID)
	}

	if err := daemon.containerd.Pause(container.ID); err != nil {
		return fmt.Errorf("Cannot pause container %s: %s", container.ID, err)
	}

	return nil
}

// killWithSignal sends the container the given signal. This wrapper for the
// host specific kill command prepares the container before attempting
// to send the signal. An error is returned if the container is paused
// or not running, or if there is a problem returned from the
// underlying kill command.
func (daemon *Daemon) killWithSignal(container *container.Container, sig int) error {
	logrus.Debugf("Sending kill signal %d to container %s", sig, container.ID)
	container.Lock()
	defer container.Unlock()

	// We could unpause the container for them rather than returning this error
	if container.Paused {
		return fmt.Errorf("Container %s is paused. Unpause the container before stopping", container.ID)
	}

	if !container.Running {
		return errNotRunning{container.ID}
	}

	if container.Config.StopSignal != "" {
		containerStopSignal, err := signal.ParseSignal(container.Config.StopSignal)
		if err != nil {
			return err
		}
		if containerStopSignal == syscall.Signal(sig) {
			container.ExitOnNext()
		}
	} else {
		container.ExitOnNext()
	}

	if !daemon.IsShuttingDown() {
		container.HasBeenManuallyStopped = true
	}

	// if the container is currently restarting we do not need to send the signal
	// to the process. Telling the monitor that it should exit on its next event
	// loop is enough
	if container.Restarting {
		return nil
	}

	if err := daemon.kill(container, sig); err != nil {
		err = fmt.Errorf("Cannot kill container %s: %s", container.ID, err)
		// if container or process not exists, ignore the error
		if strings.Contains(err.Error(), "container not found") ||
			strings.Contains(err.Error(), "no such process") {
			logrus.Warnf("container kill failed because of 'container not found' or 'no such process': %s", err.Error())
		} else {
			return err
		}
	}

	attributes := map[string]string{
		"signal": fmt.Sprintf("%d", sig),
	}
	daemon.LogContainerEventWithAttributes(container, "kill", attributes)
	return nil
}

// Update the container's Status.Health struct based on the latest probe's result.
func handleProbeResult(d *Daemon, c *container.Container, result *types.HealthcheckResult, done chan struct{}) {
	c.Lock()
	defer c.Unlock()

	// probe may have been cancelled while waiting on lock. Ignore result then
	select {
	case <-done:
		return
	default:
	}

	retries := c.Config.Healthcheck.Retries
	if retries <= 0 {
		retries = defaultProbeRetries
	}

	h := c.State.Health
	oldStatus := h.Status

	if len(h.Log) >= maxLogEntries {
		h.Log = append(h.Log[len(h.Log)+1-maxLogEntries:], result)
	} else {
		h.Log = append(h.Log, result)
	}

	if result.ExitCode == exitStatusHealthy {
		h.FailingStreak = 0
		h.Status = types.Healthy
	} else {
		// Failure (including invalid exit code)
		h.FailingStreak++
		if h.FailingStreak >= retries {
			h.Status = types.Unhealthy
		}
		// Else we're starting or healthy. Stay in that state.
	}

	if oldStatus != h.Status {
		d.LogContainerEvent(c, "health_status: "+h.Status)
	}
}

// containerUnpause resumes the container execution after the container is paused.
func (daemon *Daemon) containerUnpause(container *container.Container) error {
	container.Lock()
	defer container.Unlock()

	// We cannot unpause the container which is not paused
	if !container.Paused {
		return fmt.Errorf("Container %s is not paused", container.ID)
	}

	if err := daemon.containerd.Resume(container.ID); err != nil {
		return fmt.Errorf("Cannot unpause container %s: %s", container.ID, err)
	}

	return nil
}

// reducePsContainer is the basic representation for a container as expected by the ps command.
func (daemon *Daemon) reducePsContainer(container *container.Container, ctx *listContext, reducer containerReducer) (*types.Container, error) {
	container.Lock()
	defer container.Unlock()

	// filter containers to return
	action := includeContainerInList(container, ctx)
	switch action {
	case excludeContainer:
		return nil, nil
	case stopIteration:
		return nil, errStopIteration
	}

	// transform internal container struct into api structs
	return reducer(container, ctx)
}

// containerUnpause resumes the container execution after the container is paused.
func (daemon *Daemon) containerUnpause(container *container.Container) error {
	container.Lock()
	defer container.Unlock()

	// We cannot unpause the container which is not running
	if !container.Running {
		return derr.ErrorCodeNotRunning.WithArgs(container.ID)
	}

	// We cannot unpause the container which is not paused
	if !container.Paused {
		return derr.ErrorCodeNotPaused.WithArgs(container.ID)
	}

	if err := daemon.execDriver.Unpause(container.Command); err != nil {
		return err
	}

	container.Paused = false
	daemon.LogContainerEvent(container, "unpause")
	return nil
}

// containerUnpause resumes the container execution after the container is paused.
func (daemon *Daemon) containerUnpause(container *container.Container) error {
	container.Lock()
	defer container.Unlock()

	// We cannot unpause the container which is not running
	if !container.Running {
		return errNotRunning{container.ID}
	}

	// We cannot unpause the container which is not paused
	if !container.Paused {
		return fmt.Errorf("Container %s is not paused", container.ID)
	}

	if err := daemon.execDriver.Unpause(container.Command); err != nil {
		return fmt.Errorf("Cannot unpause container %s: %s", container.ID, err)
	}

	container.Paused = false
	daemon.LogContainerEvent(container, "unpause")
	return nil
}

func (d *Daemon) containerExec(container *container.Container, ec *exec.Config) error {
	container.Lock()
	defer container.Unlock()

	callback := func(processConfig *execdriver.ProcessConfig, pid int, chOOM <-chan struct{}) error {
		if processConfig.Tty {
			// The callback is called after the process Start()
			// so we are in the parent process. In TTY mode, stdin/out/err is the PtySlave
			// which we close here.
			if c, ok := processConfig.Stdout.(io.Closer); ok {
				c.Close()
			}
		}
		ec.Close()
		return nil
	}

	// We use a callback here instead of a goroutine and an chan for
	// synchronization purposes
	cErr := promise.Go(func() error { return d.monitorExec(container, ec, callback) })
	return ec.Wait(cErr)
}

// containerStatPath stats the filesystem resource at the specified path in this
// container. Returns stat info about the resource.
func (daemon *Daemon) containerStatPath(container *container.Container, path string) (stat *types.ContainerPathStat, err error) {
	container.Lock()
	defer container.Unlock()

	if err = daemon.Mount(container); err != nil {
		return nil, err
	}
	defer daemon.Unmount(container)

	err = daemon.mountVolumes(container)
	defer container.UnmountVolumes(true, daemon.LogVolumeEvent)
	if err != nil {
		return nil, err
	}

	resolvedPath, absPath, err := container.ResolvePath(path)
	if err != nil {
		return nil, err
	}

	return container.StatPath(resolvedPath, absPath)
}

// killWithSignal sends the container the given signal. This wrapper for the
// host specific kill command prepares the container before attempting
// to send the signal. An error is returned if the container is paused
// or not running, or if there is a problem returned from the
// underlying kill command.
func (daemon *Daemon) killWithSignal(container *container.Container, sig int) error {
	logrus.Debugf("Sending %d to %s", sig, container.ID)
	container.Lock()
	defer container.Unlock()

	// We could unpause the container for them rather than returning this error
	if container.Paused {
		return fmt.Errorf("Container %s is paused. Unpause the container before stopping", container.ID)
	}

	if !container.Running {
		return errNotRunning{container.ID}
	}

	container.ExitOnNext()

	if !daemon.IsShuttingDown() {
		container.HasBeenManuallyStopped = true
	}

	// if the container is currently restarting we do not need to send the signal
	// to the process.  Telling the monitor that it should exit on it's next event
	// loop is enough
	if container.Restarting {
		return nil
	}

	if err := daemon.kill(container, sig); err != nil {
		return fmt.Errorf("Cannot kill container %s: %s", container.ID, err)
	}

	attributes := map[string]string{
		"signal": fmt.Sprintf("%d", sig),
	}
	daemon.LogContainerEventWithAttributes(container, "kill", attributes)
	return nil
}

func (daemon *Daemon) setHostConfig(container *container.Container, hostConfig *containertypes.HostConfig) error {
	// Do not lock while creating volumes since this could be calling out to external plugins
	// Don't want to block other actions, like `docker ps` because we're waiting on an external plugin
	if err := daemon.registerMountPoints(container, hostConfig); err != nil {
		return err
	}

	container.Lock()
	defer container.Unlock()

	// Register any links from the host config before starting the container
	if err := daemon.registerLinks(container, hostConfig); err != nil {
		return err
	}

	// make sure links is not nil
	// this ensures that on the next daemon restart we don't try to migrate from legacy sqlite links
	if hostConfig.Links == nil {
		hostConfig.Links = []string{}
	}

	container.HostConfig = hostConfig
	return container.ToDisk()
}