First util functions, with corresponding unit test.

src/util.c

@@ -0,0 +1,19 @@
+/*
+ * Copyright (c) 2007 Vreixo Formoso
+ * 
+ * This file is part of the libisofs project; you can redistribute it and/or 
+ * modify it under the terms of the GNU General Public License version 2 as 
+ * published by the Free Software Foundation. See COPYING file for details.
+ */
+
+#include "util.h"
+
+int div_up(int n, int div)
+{
+    return (n + div - 1) / div;
+}
+
+int round_up(int n, int mul)
+{
+    return div_up(n, mul) * mul;
+}