- getter revolution: split backend and frontend (this is the backend)

[helm.git] / helm / ocaml / getter / http_getter_map.ml

diff --git a/helm/ocaml/getter/http_getter_map.ml b/helm/ocaml/getter/http_getter_map.ml
new file mode 100644 (file)
index 0000000..57ec927
--- /dev/null
+++ b/helm/ocaml/getter/http_getter_map.ml
@@ -0,0 +1,96 @@
+(*
+ * Copyright (C) 2003-2004:
+ *    Stefano Zacchiroli <zack@cs.unibo.it>
+ *    for the HELM Team http://helm.cs.unibo.it/
+ *
+ *  This file is part of HELM, an Hypertextual, Electronic
+ *  Library of Mathematics, developed at the Computer Science
+ *  Department, University of Bologna, Italy.
+ *
+ *  HELM 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.
+ *
+ *  HELM 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 HELM; if not, write to the Free Software
+ *  Foundation, Inc., 59 Temple Place - Suite 330, Boston,
+ *  MA  02111-1307, USA.
+ *
+ *  For details, see the HELM World-Wide-Web page,
+ *  http://helm.cs.unibo.it/
+ *)
+
+exception Key_already_in of string;;
+exception Key_not_found of string;;
+
+class map dbname =
+  let perm = 420 in (* permission 644 in decimal notation *)
+  let open_dbm () = Dbm.opendbm dbname [ Dbm.Dbm_rdwr; Dbm.Dbm_create ] perm in
+  
+  object (self)
+
+    inherit ThreadSafe.threadSafe
+
+    val mutable db = open_dbm ()
+
+    (*initializer Gc.finalise Dbm.close db  (* close db on GC *)*)
+
+    method add key value =
+      self#doWriter (lazy (
+        try
+          Dbm.add db key value
+        with Dbm.Dbm_error "Entry already exists" -> raise (Key_already_in key)
+      ))
+
+    method replace key value =
+      self#doWriter (lazy (
+        Dbm.replace db key value
+      ))
+
+    method remove key =
+      self#doWriter (lazy (
+        try
+          Dbm.remove db key
+        with Dbm.Dbm_error "dbm_delete" -> raise (Key_not_found key)
+      ))
+
+    method resolve key =
+      self#doReader (lazy (
+        try Dbm.find db key with Not_found -> raise (Key_not_found key)
+      ))
+
+    method iter (f: string -> string -> unit) =
+      self#doReader (lazy (
+        Dbm.iter f db
+      ))
+
+    method sync =
+      self#doWriter (lazy (
+        Dbm.close db;
+        db <- open_dbm ()
+      ))
+
+    method clear =
+      self#doWriter (lazy (
+        Dbm.close db;
+        List.iter
+          (fun ext ->
+            let file = dbname ^ ext in
+            if Sys.file_exists file then Sys.remove file)
+          [".dir"; ".pag"; ".db"];
+        db <- open_dbm ()
+      ))
+
+    method close =
+      self#doWriter (lazy (
+        Dbm.close db
+      ))
+
+  end
+