blob: 7aab46061913b654ec0438c0caf9e3073c4f69e4 [file] [log] [blame]
// +build linux
package libcontainer
import (
"fmt"
"os"
"path/filepath"
"syscall"
"github.com/Sirupsen/logrus"
"github.com/opencontainers/runc/libcontainer/configs"
"github.com/opencontainers/runc/libcontainer/utils"
)
func newStateTransitionError(from, to containerState) error {
return &stateTransitionError{
From: from.status().String(),
To: to.status().String(),
}
}
// stateTransitionError is returned when an invalid state transition happens from one
// state to another.
type stateTransitionError struct {
From string
To string
}
func (s *stateTransitionError) Error() string {
return fmt.Sprintf("invalid state transition from %s to %s", s.From, s.To)
}
type containerState interface {
transition(containerState) error
destroy() error
status() Status
}
func destroy(c *linuxContainer) error {
if !c.config.Namespaces.Contains(configs.NEWPID) {
if err := signalAllProcesses(c.cgroupManager, syscall.SIGKILL); err != nil {
logrus.Warn(err)
}
}
err := c.cgroupManager.Destroy()
if rerr := os.RemoveAll(c.root); err == nil {
err = rerr
}
c.initProcess = nil
if herr := runPoststopHooks(c); err == nil {
err = herr
}
c.state = &stoppedState{c: c}
return err
}
func runPoststopHooks(c *linuxContainer) error {
if c.config.Hooks != nil {
s := configs.HookState{
Version: c.config.Version,
ID: c.id,
Root: c.config.Rootfs,
BundlePath: utils.SearchLabels(c.config.Labels, "bundle"),
}
for _, hook := range c.config.Hooks.Poststop {
if err := hook.Run(s); err != nil {
return err
}
}
}
return nil
}
// stoppedState represents a container is a stopped/destroyed state.
type stoppedState struct {
c *linuxContainer
}
func (b *stoppedState) status() Status {
return Stopped
}
func (b *stoppedState) transition(s containerState) error {
switch s.(type) {
case *runningState, *restoredState:
b.c.state = s
return nil
case *stoppedState:
return nil
}
return newStateTransitionError(b, s)
}
func (b *stoppedState) destroy() error {
return destroy(b.c)
}
// runningState represents a container that is currently running.
type runningState struct {
c *linuxContainer
}
func (r *runningState) status() Status {
return Running
}
func (r *runningState) transition(s containerState) error {
switch s.(type) {
case *stoppedState:
t, err := r.c.runType()
if err != nil {
return err
}
if t == Running {
return newGenericError(fmt.Errorf("container still running"), ContainerNotStopped)
}
r.c.state = s
return nil
case *pausedState:
r.c.state = s
return nil
case *runningState:
return nil
}
return newStateTransitionError(r, s)
}
func (r *runningState) destroy() error {
t, err := r.c.runType()
if err != nil {
return err
}
if t == Running {
return newGenericError(fmt.Errorf("container is not destroyed"), ContainerNotStopped)
}
return destroy(r.c)
}
type createdState struct {
c *linuxContainer
}
func (i *createdState) status() Status {
return Created
}
func (i *createdState) transition(s containerState) error {
switch s.(type) {
case *runningState, *pausedState, *stoppedState:
i.c.state = s
return nil
case *createdState:
return nil
}
return newStateTransitionError(i, s)
}
func (i *createdState) destroy() error {
i.c.initProcess.signal(syscall.SIGKILL)
return destroy(i.c)
}
// pausedState represents a container that is currently pause. It cannot be destroyed in a
// paused state and must transition back to running first.
type pausedState struct {
c *linuxContainer
}
func (p *pausedState) status() Status {
return Paused
}
func (p *pausedState) transition(s containerState) error {
switch s.(type) {
case *runningState, *stoppedState:
p.c.state = s
return nil
case *pausedState:
return nil
}
return newStateTransitionError(p, s)
}
func (p *pausedState) destroy() error {
t, err := p.c.runType()
if err != nil {
return err
}
if t != Running && t != Created {
if err := p.c.cgroupManager.Freeze(configs.Thawed); err != nil {
return err
}
return destroy(p.c)
}
return newGenericError(fmt.Errorf("container is paused"), ContainerPaused)
}
// restoredState is the same as the running state but also has accociated checkpoint
// information that maybe need destroyed when the container is stopped and destroy is called.
type restoredState struct {
imageDir string
c *linuxContainer
}
func (r *restoredState) status() Status {
return Running
}
func (r *restoredState) transition(s containerState) error {
switch s.(type) {
case *stoppedState, *runningState:
return nil
}
return newStateTransitionError(r, s)
}
func (r *restoredState) destroy() error {
if _, err := os.Stat(filepath.Join(r.c.root, "checkpoint")); err != nil {
if !os.IsNotExist(err) {
return err
}
}
return destroy(r.c)
}
// loadedState is used whenever a container is restored, loaded, or setting additional
// processes inside and it should not be destroyed when it is exiting.
type loadedState struct {
c *linuxContainer
s Status
}
func (n *loadedState) status() Status {
return n.s
}
func (n *loadedState) transition(s containerState) error {
n.c.state = s
return nil
}
func (n *loadedState) destroy() error {
if err := n.c.refreshState(); err != nil {
return err
}
return n.c.state.destroy()
}