1 files changed, 76 insertions, 0 deletions
diff --git a/tools/ocaml/xenstored/symbol.ml b/tools/ocaml/xenstored/symbol.ml
new file mode 100644
index 0000000000..4420c6a4d7
--- /dev/null
+++ b/tools/ocaml/xenstored/symbol.ml
@@ -0,0 +1,76 @@
+(*
+ * Copyright (C) 2006-2007 XenSource Ltd.
+ * Copyright (C) 2008      Citrix Ltd.
+ * Author Thomas Gazagnaire <thomas.gazagnaire@eu.citrix.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published
+ * by the Free Software Foundation; version 2.1 only. with the special
+ * exception on linking described in file LICENSE.
+ *
+ * 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 Lesser General Public License for more details.
+ *)
+
+type t = int
+
+type 'a record = { data: 'a; mutable garbage: bool }
+let int_string_tbl : (int,string record) Hashtbl.t = Hashtbl.create 1024
+let string_int_tbl : (string,int) Hashtbl.t = Hashtbl.create 1024
+
+let created_counter = ref 0
+let used_counter = ref 0
+
+let count = ref 0
+let rec fresh () =
+	if Hashtbl.mem int_string_tbl !count
+	then begin
+		incr count;
+		fresh ()
+	end else
+		!count
+
+let new_record v = { data=v; garbage=false }
+
+let of_string name =
+	if Hashtbl.mem string_int_tbl name
+	then begin
+		incr used_counter;
+		Hashtbl.find string_int_tbl name
+	end else begin
+		let i = fresh () in
+		incr created_counter;
+		Hashtbl.add string_int_tbl name i;
+		Hashtbl.add int_string_tbl i (new_record name);
+		i
+	end
+
+let to_string i =
+	(Hashtbl.find int_string_tbl i).data
+
+let mark_all_as_unused () =
+	Hashtbl.iter (fun _ v -> v.garbage <- true) int_string_tbl
+
+let mark_as_used symb =
+	let record1 = Hashtbl.find int_string_tbl symb in
+		record1.garbage <- false
+
+let garbage () =
+	let records = Hashtbl.fold (fun symb record accu ->
+		if record.garbage then (symb, record.data) :: accu else accu
+	) int_string_tbl [] in
+	let remove (int,string) =
+		Hashtbl.remove int_string_tbl int;
+		Hashtbl.remove string_int_tbl string
+	in
+	created_counter := 0;
+	used_counter := 0;
+	List.iter remove records
+
+let stats () =
+	Hashtbl.length string_int_tbl
+
+let created () = !created_counter
+let used () = !used_counter