Refactoring plugins

[hcoop/domtool2.git] / src / slave.sml

diff --git a/src/slave.sml b/src/slave.sml
new file mode 100644 (file)
index 0000000..b08d41d
--- /dev/null
+++ b/src/slave.sml
@@ -0,0 +1,61 @@
+(* HCoop Domtool (http://hcoop.sourceforge.net/)
+ * Copyright (c) 2006, Adam Chlipala
+ *
+ * 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.
+ *)
+
+(* Code for receiving and executing configuration files *)
+
+structure Slave :> SLAVE = struct
+
+datatype file_action =
+        Add
+       | Delete
+       | Modify
+
+type file_status = {action : file_action,
+                   domain : string,
+                   file : string}
+                  
+val fileHandler = ref (fn _ : file_status => ())
+val preHandler = ref (fn () => ())
+val postHandler = ref (fn () => ())
+                 
+fun registerFileHandler handler =
+    let
+       val old = !fileHandler
+    in
+       fileHandler := (fn x => (handler x; old x))
+    end
+
+fun registerPreHandler handler =
+    let
+       val old = !preHandler
+    in
+       preHandler := (fn () => (handler (); old ()))
+    end
+
+fun registerPostHandler handler =
+    let
+       val old = !postHandler
+    in
+       postHandler := (fn () => (handler (); old ()))
+    end
+
+fun handleChanges fs = (!preHandler ();
+                       app (!fileHandler) fs;
+                       !postHandler ())
+
+end