ntpd: with -q, exit after 60 seconds even if time is not synced.

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

1 files changed, 22 insertions, 3 deletions

diff --git a/networking/ntpd.c b/networking/ntpd.c
index fb3ef2e3c..6707e9bdb 100644
--- a/networking/ntpd.c
+++ b/networking/ntpd.c
@@ -1920,9 +1920,28 @@ static NOINLINE void ntp_init(char **argv)
         if (opts & OPT_N)
                 setpriority(PRIO_PROCESS, 0, -15);
 
-        bb_signals((1 << SIGTERM) | (1 << SIGINT), record_signo);
-        /* Removed SIGHUP here: */
-        bb_signals((1 << SIGPIPE) | (1 << SIGCHLD), SIG_IGN);
+        /* If network is up, syncronization occurs in ~10 seconds.
+         * We give "ntpd -q" a full minute to finish, then we exit.
+         *
+         * I tested ntpd 4.2.6p1 and apparently it never exits
+         * (will try forever), but it does not feel right.
+         * The goal of -q is to act like ntpdate: set time
+         * after a reasonably small period of polling, or fail.
+         */
+        if (opts & OPT_q)
+                alarm(60);
+
+        bb_signals(0
+                | (1 << SIGTERM)
+                | (1 << SIGINT)
+                | (1 << SIGALRM)
+                , record_signo
+        );
+        bb_signals(0
+                | (1 << SIGPIPE)
+                | (1 << SIGCHLD)
+                , SIG_IGN
+        );
 }
 
 int ntpd_main(int argc UNUSED_PARAM, char **argv) MAIN_EXTERNALLY_VISIBLE;