daemon: Reimplement ‘vfs_type’ API in OCaml.

daemon/mountable.ml

@@ -0,0 +1,43 @@
+(* guestfs-inspection
+ * Copyright (C) 2009-2017 Red Hat Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ *)
+
+open Printf
+
+type t = {
+  m_type : mountable_type;
+  m_device : string;
+}
+and mountable_type =
+  | MountableDevice
+  | MountablePath
+  | MountableBtrfsVol of string (* volume *)
+
+let to_string { m_type = t; m_device = device } =
+  match t with
+  | MountableDevice | MountablePath -> device
+  | MountableBtrfsVol volume ->
+     sprintf "btrfsvol:%s/%s" device volume
+
+let of_device device =
+  { m_type = MountableDevice; m_device = device }
+
+let of_path path =
+  { m_type = MountablePath; m_device = path }
+
+let of_btrfsvol device volume =
+  { m_type = MountableBtrfsVol volume; m_device = device }