libcontainer: Add a helper func to set CriuPath

Added a helper func to set CriuPath for LinuxFactory.

Signed-off-by: Yang Hongyang <imhy.yang@gmail.com>

libcontainer/factory_linux.go

@@ -103,6 +103,15 @@ func TmpfsRoot(l *LinuxFactory) error {
 	return nil
 }
 
+// CriuPath returns an option func to configure a LinuxFactory with the
+// provided criupath
+func CriuPath(criupath string) func(*LinuxFactory) error {
+	return func(l *LinuxFactory) error {
+		l.CriuPath = criupath
+		return nil
+	}
+}
+
 // New returns a linux based container factory based in the root directory and
 // configures the factory with the provided option funcs.
 func New(root string, options ...func(*LinuxFactory) error) (Factory, error) {

utils_linux.go

@@ -37,10 +37,7 @@ func loadFactory(context *cli.Context) (libcontainer.Factory, error) {
 			return nil, fmt.Errorf("systemd cgroup flag passed, but systemd support for managing cgroups is not available")
 		}
 	}
-	return libcontainer.New(abs, cgroupManager, func(l *libcontainer.LinuxFactory) error {
-		l.CriuPath = context.GlobalString("criu")
-		return nil
-	})
+	return libcontainer.New(abs, cgroupManager, libcontainer.CriuPath(context.GlobalString("criu")))
 }
 
 // getContainer returns the specified container instance by loading it from state