Remove the nullState

Add a "createdState" in its place since I think that better describes
what its used for.

Signed-off-by: Doug Davis <dug@us.ibm.com>

libcontainer/container.go

@@ -14,8 +14,11 @@ import (
 type Status int
 
 const (
+	// The container exists but has not been run yet
+	Created Status = iota
+
 	// The container exists and is running.
-	Running Status = iota + 1
+	Running
 
 	// The container exists, it is in the process of being paused.
 	Pausing
@@ -32,6 +35,8 @@ const (
 
 func (s Status) String() string {
 	switch s {
+	case Created:
+		return "created"
 	case Running:
 		return "running"
 	case Pausing:
@@ -43,7 +48,7 @@ func (s Status) String() string {
 	case Destroyed:
 		return "destroyed"
 	default:
-		return "undefined"
+		return "unknown"
 	}
 }
 

libcontainer/container_linux_test.go

@@ -166,7 +166,7 @@ func TestGetContainerState(t *testing.T) {
 			},
 		},
 	}
-	container.state = &nullState{c: container}
+	container.state = &createdState{c: container}
 	state, err := container.State()
 	if err != nil {
 		t.Fatal(err)

libcontainer/factory_linux.go

@@ -202,7 +202,7 @@ func (l *LinuxFactory) Load(id string) (Container, error) {
 		cgroupManager: l.NewCgroupsManager(state.Config.Cgroups, state.CgroupPaths),
 		root:          containerRoot,
 	}
-	c.state = &nullState{c: c}
+	c.state = &createdState{c: c, s: Created}
 	if err := c.refreshState(); err != nil {
 		return nil, err
 	}

libcontainer/state_linux.go

@@ -117,7 +117,7 @@ func (r *runningState) transition(s containerState) error {
 		}
 		r.c.state = s
 		return nil
-	case *pausedState, *nullState:
+	case *pausedState:
 		r.c.state = s
 		return nil
 	case *runningState:
@@ -202,22 +202,22 @@ func (r *restoredState) destroy() error {
 	return destroy(r.c)
 }
 
-// nullState is used whenever a container is restored, loaded, or setting additional
+// createdState is used whenever a container is restored, loaded, or setting additional
 // processes inside and it should not be destroyed when it is exiting.
-type nullState struct {
+type createdState struct {
 	c *linuxContainer
 	s Status
 }
 
-func (n *nullState) status() Status {
+func (n *createdState) status() Status {
 	return n.s
 }
 
-func (n *nullState) transition(s containerState) error {
+func (n *createdState) transition(s containerState) error {
 	n.c.state = s
 	return nil
 }
 
-func (n *nullState) destroy() error {
+func (n *createdState) destroy() error {
 	return nil
 }

libcontainer/state_linux_test.go

@@ -69,9 +69,9 @@ func TestRestoredStateTransition(t *testing.T) {
 			t.Fatal(err)
 		}
 	}
-	err := s.transition(&nullState{})
+	err := s.transition(&createdState{})
 	if err == nil {
-		t.Fatal("transition to null state should fail")
+		t.Fatal("transition to created state should fail")
 	}
 	if !isStateTransitionError(err) {
 		t.Fatal("expected stateTransitionError")