usbcan_relay: add standalone buttons reactions

F0-nolib/usbcan_relay/custom_buttons.h

@@ -0,0 +1,25 @@
+/*
+ * This file is part of the canrelay project.
+ * Copyright 2021 Edward V. Emelianov <edward.emelianoff@gmail.com>.
+ *
+ * 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 3 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, see <http://www.gnu.org/licenses/>.
+ */
+
+#pragma once
+#ifndef CUSTOM_BUTTONS_H__
+#define CUSTOM_BUTTONS_H__
+
+void custom_buttons_process();
+
+#endif // CUSTOM_BUTTONS_H__