linux_container: ct.Destroy() returns error if CT isn't stopped

Signed-off-by: Andrew Vagin <avagin@openvz.org>

error.go

@@ -14,6 +14,7 @@ const (
 	// Container errors
 	ContainerNotExists
 	ContainerPaused
+	ContainerNotStopped
 
 	// Common errors
 	ConfigInvalid
@@ -34,6 +35,8 @@ func (c ErrorCode) String() string {
 		return "System error"
 	case ContainerNotExists:
 		return "Container does not exist"
+	case ContainerNotStopped:
+		return "Container isn't stopped"
 	default:
 		return "Unknown error"
 	}

linux_container.go

@@ -58,6 +58,15 @@ func (c *linuxContainer) StartProcess(config *ProcessConfig) (int, error) {
 }
 
 func (c *linuxContainer) Destroy() error {
+	state, err := c.RunState()
+	if err != nil {
+		return err
+	}
+
+	if state != Destroyed {
+		return newGenericError(nil, ContainerNotStopped)
+	}
+
 	glog.Info("destroy container")
 	panic("not implemented")
 }