add simplest web interface

modbus_relay/web_management/relay_daemon/server.h

@@ -0,0 +1,29 @@
+/*
+ * This file is part of the modbus_relay project.
+ * Copyright 2025 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/>.
+ */
+
+#include <modbus/modbus.h>
+
+// timeout for socket closing if nothing received
+#define SOCKET_TIMEOUT  (60.0)
+// timeout to turn relays off
+#define RELAYS_TIMEOUT  (10.0)
+// time interval for MODBUS data polling (seconds)
+#define T_INTERVAL      (1.)
+
+void runserver(const char *port, modbus_t *ctx);
+int closeserver();