ntpd: add -q option. By Adam Tkac.

function                                             old     new   delta
settime                                              347     375     +28
packed_usage                                       26681   26693     +12
ntpd_main                                           3282    3251     -31
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 2/1 up/down: 40/-31)              Total: 9 bytes

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

2 files changed, 30 insertions, 31 deletions

diff --git a/include/usage.h b/include/usage.h
index 48cb8df7d..461f5fca1 100644
--- a/include/usage.h
+++ b/include/usage.h
@@ -3211,13 +3211,14 @@
        "Address:    127.0.0.1\n"
 
 #define ntpd_trivial_usage \
-        "[-dngl] [-p PEER]..."
+        "[-dngql] [-p PEER]..."
 #define ntpd_full_usage "\n\n" \
        "NTP client/server\n" \
      "\nOptions:" \
      "\n        -d      Verbose" \
      "\n        -n      Do not daemonize" \
      "\n        -g      Set system time even if offset is > 1000 sec" \
+     "\n        -q      Quit after clock is set" \
      "\n        -l      Run as server on port 123" \
      "\n        -p PEER Obtain time from PEER (may be repeated)" \
 
diff --git a/networking/ntpd.c b/networking/ntpd.c
index 62a00a5bf..8ee42e627 100644
--- a/networking/ntpd.c
+++ b/networking/ntpd.c
@@ -152,6 +152,16 @@ typedef struct {
         uint8_t                  trustlevel;
 } ntp_peer_t;
 
+enum {
+        OPT_n = (1 << 0),
+        OPT_g = (1 << 1),
+        OPT_q = (1 << 2),
+        /* Insert new options above this line. */
+        /* Non-compat options: */
+        OPT_p = (1 << 3),
+        OPT_l = (1 << 4),
+};
+
 
 struct globals {
         unsigned        verbose;
@@ -164,7 +174,6 @@ struct globals {
         uint8_t         settime;
         uint8_t         firstadj;
         smallint        peer_cnt;
-
 };
 #define G (*ptr_to_globals)
 
@@ -468,14 +477,14 @@ settime(double offset)
         char            buf[80];
         time_t          tval;
 
-#if 0
         if (!G.settime)
-                return;
-#endif
+                goto bail;
+
+        G.settime = 0;
 
         /* if the offset is small, don't call settimeofday */
         if (offset < SETTIME_MIN_OFFSET && offset > -SETTIME_MIN_OFFSET)
-                return;
+                goto bail;
 
         gettimeofday(&curtime, NULL); /* never fails */
 
@@ -486,11 +495,9 @@ settime(double offset)
 
         if (settimeofday(&curtime, NULL) == -1) {
                 bb_error_msg("settimeofday");
-                return;
+                goto bail;
         }
 
-        G.settime = 0;
-
         tval = curtime.tv_sec;
         strftime(buf, sizeof(buf), "%a %b %e %H:%M:%S %Z %Y", localtime(&tval));
 
@@ -504,6 +511,10 @@ settime(double offset)
                 if (p->deadline)
                         p->deadline -= offset;
         }
+
+ bail:
+        if (option_mask32 & OPT_q)
+                exit(0);
 }
 
 static void
@@ -669,8 +680,7 @@ client_dispatch(ntp_peer_t *p)
                         offset->offset, offset->delay, (int) interval);
 
         client_update(p);
-        if (!G.settime)
-                settime(offset->offset);
+        settime(offset->offset);
 
         if (++p->shift >= OFFSET_ARRAY_SIZE)
                 p->shift = 0;
@@ -817,13 +827,6 @@ server_dispatch(int fd)
  *      Note: The kernel time discipline is disabled with this option.
  */
 
-enum {
-        OPT_n = (1 << 0),
-        OPT_g = (1 << 1),
-        OPT_p = (1 << 2),
-        OPT_l = (1 << 3),
-};
-
 /* By doing init in a separate function we decrease stack usage
  * in main loop.
  */
@@ -840,7 +843,7 @@ static NOINLINE void ntp_init(char **argv)
         peers = NULL;
         opt_complementary = "dd:p::"; /* d: counter, p: list */
         opts = getopt32(argv,
-                        "ng" /* compat */
+                        "ngq" /* compat */
                         "p:"IF_FEATURE_NTPD_SERVER("l") /* NOT compat */
                         "d" /* compat */
                         "46aAbLNx", /* compat, ignored */
@@ -891,7 +894,6 @@ int ntpd_main(int argc UNUSED_PARAM, char **argv) MAIN_EXTERNALLY_VISIBLE;
 int ntpd_main(int argc UNUSED_PARAM, char **argv)
 {
         struct globals g;
-        unsigned new_cnt;
         struct pollfd *pfd;
         ntp_peer_t **idx2peer;
 
@@ -900,13 +902,12 @@ int ntpd_main(int argc UNUSED_PARAM, char **argv)
 
         ntp_init(argv);
 
-        new_cnt = g.peer_cnt;
-        idx2peer = xzalloc(sizeof(void *) * new_cnt);
-#if ENABLE_FEATURE_NTPD_SERVER
-        if (g.listen_fd != -1)
-                new_cnt++;
-#endif
-        pfd = xzalloc(sizeof(pfd[0]) * new_cnt);
+        {
+                unsigned new_cnt = g.peer_cnt;
+                idx2peer = xzalloc(sizeof(void *) * new_cnt);
+                /* if ENABLE_FEATURE_NTPD_SERVER, + 1 for listen_fd: */
+                pfd = xzalloc(sizeof(pfd[0]) * (new_cnt + ENABLE_FEATURE_NTPD_SERVER));
+        }
 
         while (!bb_got_signal) {
                 llist_t *item;
@@ -964,11 +965,8 @@ int ntpd_main(int argc UNUSED_PARAM, char **argv)
                         }
                 }
 
-                if (g.settime
-                 && ((trial_cnt > 0 && sent_cnt == 0) || g.peer_cnt == 0)
-                ) {
+                if ((trial_cnt > 0 && sent_cnt == 0) || g.peer_cnt == 0)
                         settime(0);     /* no good peers, don't wait */
-                }
 
                 timeout = nextaction - time(NULL);
                 if (timeout < 0)