package daemon // import "github.com/docker/docker/daemon"

 import (

 	"context"

 	"fmt"
 

 	"github.com/docker/docker/container"

 	"github.com/sirupsen/logrus"

 )

 
 // ContainerPause pauses a container

 func (daemon *Daemon) ContainerPause(name string) error {

 	container, err := daemon.GetContainer(name)

 	if err != nil {
 		return err
 	}

 	return daemon.containerPause(container)

 }

 
 // 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 errNotPaused(container.ID)

 	}
 

 	// We cannot Pause the container which is restarting
 	if container.Restarting {

 		return errContainerIsRestarting(container.ID)

 	}
 

 	if err := daemon.containerd.Pause(context.Background(), container.ID); err != nil {

 		return fmt.Errorf("Cannot pause container %s: %s", container.ID, err)

 	}

 	container.Paused = true
 	daemon.setStateCounter(container)
 	daemon.updateHealthMonitor(container)
 	daemon.LogContainerEvent(container, "pause")
 
 	if err := container.CheckpointTo(daemon.containersReplica); err != nil {
 		logrus.WithError(err).Warn("could not save container to disk")
 	}
 

 	return nil
 }