Add IsoFileSource implementation for local filesystem.

src/fsource.c

@@ -0,0 +1,23 @@
+/*
+ * 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 "fsource.h"
+#include <stdlib.h>
+
+void iso_file_source_ref(IsoFileSource *src)
+{
+	++src->refcount;
+}
+
+void iso_file_source_unref(IsoFileSource *src)
+{
+	if (--src->refcount == 0) {
+		src->free(src);
+		free(src);
+	}
+}