dotcloud/docker

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

import (
    "context"
    "fmt"

    containertypes "github.com/docker/docker/api/types/container"
    "github.com/docker/docker/api/types/events"
    "github.com/docker/docker/container"
)

// ContainerRestart stops and starts a container. It attempts to
// gracefully stop the container within the given timeout, forcefully
// stopping it if the timeout is exceeded. If given a negative
// timeout, ContainerRestart will wait forever until a graceful
// stop. Returns an error if the container cannot be found, or if
// there is an underlying error at any stage of the restart.
func (daemon *Daemon) ContainerRestart(ctx context.Context, name string, options containertypes.StopOptions) error {
    ctr, err := daemon.GetContainer(name)
    if err != nil {
        return err
    }
    err = daemon.containerRestart(ctx, daemon.config(), ctr, options)
    if err != nil {
        return fmt.Errorf("Cannot restart container %s: %v", name, err)
    }
    return nil
}

// containerRestart attempts to gracefully stop and then start the
// container. When stopping, wait for the given duration in seconds to
// gracefully stop, before forcefully terminating the container. If
// given a negative duration, wait forever for a graceful stop.
func (daemon *Daemon) containerRestart(ctx context.Context, daemonCfg *configStore, container *container.Container, options containertypes.StopOptions) error {
    // Restarting is expected to be an atomic operation, and cancelling
    // the request should not cancel the stop -> start sequence.
    ctx = context.WithoutCancel(ctx)

    // Determine isolation. If not specified in the hostconfig, use daemon default.
    actualIsolation := container.HostConfig.Isolation
    if containertypes.Isolation.IsDefault(actualIsolation) {
        actualIsolation = daemon.defaultIsolation
    }

    // Avoid unnecessarily unmounting and then directly mounting
    // the container when the container stops and then starts
    // again. We do not do this for Hyper-V isolated containers
    // (implying also on Windows) as the HCS must have exclusive
    // access to mount the containers filesystem inside the utility
    // VM.
    if !containertypes.Isolation.IsHyperV(actualIsolation) {
        if err := daemon.Mount(container); err == nil {
            defer daemon.Unmount(container)
        }
    }

    if container.IsRunning() {
        container.Lock()
        container.HasBeenManuallyRestarted = true
        container.Unlock()

        err := daemon.containerStop(ctx, container, options)
        if err != nil {
            return err
        }
    }

    if err := daemon.containerStart(ctx, daemonCfg, container, "", "", true); err != nil {
        return err
    }

    daemon.LogContainerEvent(container, events.ActionRestart)
    return nil
}