Handle SIGHUP

Handle SIGHUP so that the registered exit handlers are called to restore
the terminal back to its orignal state.

src/main.c

@@ -29,11 +29,15 @@
 #include "log.h"
 #include "error.h"
 #include "print.h"
+#include "signals.h"
 
 int main(int argc, char *argv[])
 {
     int status = 0;
 
+    /* Handle received signals */
+    signal_handlers_install();
+
     /* Add error exit handler */
     atexit(&error_exit);
 

src/meson.build

@@ -11,7 +11,8 @@ tio_sources = [
   'misc.c',
   'tty.c',
   'print.c',
-  'configfile.c'
+  'configfile.c',
+  'signals.c'
 ]
 
 tio_dep = dependency('inih', required: true)

src/signals.c

@@ -0,0 +1,41 @@
+/*
+ * tio - a simple serial terminal I/O tool
+ *
+ * Copyright (c) 2022  Martin Lund
+ *
+ * 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 2
+ * 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, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301, USA.
+ */
+
+#include "config.h"
+#include <stdio.h>
+#include <stdlib.h>
+#include <signal.h>
+#include <errno.h>
+#include "error.h"
+#include "print.h"
+#include "misc.h"
+
+static void signal_handler(int signum)
+{
+    UNUSED(signum);
+    tio_printf("Received hangup signal!");
+    exit(EXIT_FAILURE);
+}
+
+void signal_handlers_install(void)
+{
+    signal(SIGHUP, signal_handler);
+}

src/signals.h

@@ -0,0 +1,24 @@
+/*
+ * tio - a simple serial terminal I/O tool
+ *
+ * Copyright (c) 2022  Martin Lund
+ *
+ * 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 2
+ * 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, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301, USA.
+ */
+
+#pragma once
+
+void signal_handlers_install();