reboot: Ignore SIGTERM at halt/poweroff

We want to emulate the behavior of the reboot() syscall on success.
Primarily for a coherency/symmetry, but also to prevent printing
a new shell prompt in the middle of system shutdown messages.

Signed-off-by: Joachim Nilsson <troglobit@gmail.com>

reboot.c

@@ -85,6 +85,11 @@ static void transform(char *nm)
 	}
 }
 
+static void sig(int signo)
+{
+	(void)signo;		/* NOP */
+}
+
 static int usage(int rc)
 {
 	fprintf(stderr, "Usage: %s [OPTIONS]\n\n"
@@ -144,6 +149,9 @@ int main(int argc, char *argv[])
 	/* Check for any overrides */
 	transform(NULL);
 
+	/* Catch and ignore SIGTERM on halt/poweroff */
+	signal(SIGTERM, sig);
+
 	if (force) {
 		switch (cmd) {
 		case CMD_REBOOT: