Fix cgroups detection (#134)

* Use a proper enum to fix CGroupsV2 detection

* Fix argument order in info messages

Author: agners

cgroup/cgroup.go

@@ -24,7 +24,7 @@ const (
 type CGroupVersion int
 
 const (
-	CGroupUnknown CGroupVersion = 0
+	CGroupUnknown CGroupVersion = iota
 	CGroupV1
 	CGroupV2
 )
@@ -71,7 +71,7 @@ func (d cgroup) AddDevicesAllowed(containerID string, permission string) (bool,
 			logging.Info.Printf("Successfully called runc for '%s', output %s", containerID, stdoutStderr)
 		}
 
-		logging.Info.Printf("Permission '%s', granted for Container '%s' via runc", containerID, permission)
+		logging.Info.Printf("Permission '%s', granted for Container '%s' via runc", permission, containerID)
 		return true, nil
 	} else {
 		// Make sure path is relative to cgroupFSDockerDevices
@@ -98,7 +98,7 @@ func (d cgroup) AddDevicesAllowed(containerID string, permission string) (bool,
 			return false, dbus.MakeFailedError(fmt.Errorf("Can't write CGroup permission '%s': %s", permission, err))
 		}
 
-		logging.Info.Printf("Permission '%s', granted for Container '%s' via CGroup devices.allow", containerID, permission)
+		logging.Info.Printf("Permission '%s', granted for Container '%s' via CGroup devices.allow", permission, containerID)
 		return true, nil
 	}
 }
@@ -112,8 +112,10 @@ func InitializeDBus(conn *dbus.Conn) {
 	// Check for CGroups v2
 	if _, err := os.Stat("/sys/fs/cgroup/cgroup.controllers"); err == nil {
 		d.cgroupVersion = CGroupV2
+		logging.Info.Printf("Detected CGroups Version 2")
 	} else {
 		d.cgroupVersion = CGroupV1
+		logging.Info.Printf("Detected CGroups Version 1")
 	}
 
 	err := conn.Export(d, objectPath, ifaceName)