libifupdown: add config file loader

libifupdown/config-file.h

@@ -0,0 +1,29 @@
+/*
+ * libifupdown/config-file.h
+ * Purpose: config file loading
+ *
+ * Copyright (c) 2020 Ariadne Conill <ariadne@dereferenced.org>
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * This software is provided 'as is' and without any warranty, express or
+ * implied.  In no event shall the authors be liable for any damages arising
+ * from the use of this software.
+ */
+
+#ifndef LIBIFUPDOWN__CONFIG_FILE_H
+#define LIBIFUPDOWN__CONFIG_FILE_H
+
+#include <stdbool.h>
+
+struct lif_config_file {
+	bool allow_addon_scripts;
+};
+
+extern struct lif_config_file lif_config;
+
+extern bool lif_config_load(const char *filename);
+
+#endif