initctl: Add support for showing current runlevel

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

initctl.c

@@ -82,7 +82,7 @@ static int toggle_debug(char *UNUSED(arg))
 	return do_send(&rq, sizeof(rq));
 }
 
-static int set_runlevel(char *arg)
+static int do_runlevel(char *arg)
 {
 	struct init_request rq = {
 		.magic = INIT_MAGIC,
@@ -90,6 +90,13 @@ static int set_runlevel(char *arg)
 		.runlevel = (int)arg[0],
 	};
 
+	/* Not compatible with the SysV runlevel(8) command, it prints
+	 * "PREVLEVEL RUNLEVEL", we just print the current runlevel. */
+	if (!rq.runlevel) {
+		printf("%d\n", runlevel_get());
+		return 0;
+	}
+
 	return do_send(&rq, sizeof(rq));
 }
 
@@ -200,7 +207,7 @@ static int usage(int rc)
 		"Commands:\n"
 		"  debug                 Toggle Finit debug\n"
 		"  reload                Reload *.conf in /etc/finit.d/\n"
-		"  runlevel <0-9>        Change runlevel: 0 halt, 6 reboot\n"
+		"  runlevel [0-9]        Show or set runlevel: 0 halt, 6 reboot\n"
 		"  status                Show status of services\n"
 		"  start    <JOB|NAME>   Start stopped job or service\n"
 		"  stop     <JOB|NAME>   Stop running job or service\n"
@@ -217,7 +224,7 @@ int main(int argc, char *argv[])
 	command_t command[] = {
 		{ "debug",    toggle_debug },
 		{ "reload",   do_reload    },
-		{ "runlevel", set_runlevel },
+		{ "runlevel", do_runlevel  },
 		{ "status",   show_status  },
 		{ "start",    do_start     },
 		{ "stop",     do_stop      },