ntpd: add -w "watch" option, useful for debugging to look at our own data

Also fixed a small buglet discovered using -w

function                                             old     new   delta
recv_and_process_peer_pkt                            895     944     +49
select_and_cluster                                  1132    1150     +18
packed_usage                                       26769   26767      -2

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

1 files changed, 26 insertions, 13 deletions

diff --git a/networking/ntpd.c b/networking/ntpd.c
index 771a75a69..84ee54307 100644
--- a/networking/ntpd.c
+++ b/networking/ntpd.c
@@ -192,8 +192,9 @@ enum {
         OPT_x = (1 << 3),
         /* Insert new options above this line. */
         /* Non-compat options: */
-        OPT_p = (1 << 4),
-        OPT_l = (1 << 5) * ENABLE_FEATURE_NTPD_SERVER,
+        OPT_w = (1 << 4),
+        OPT_p = (1 << 5),
+        OPT_l = (1 << 6) * ENABLE_FEATURE_NTPD_SERVER,
 };
 
 struct globals {
@@ -940,7 +941,7 @@ select_and_cluster(void)
                 double min_jitter = min_jitter;
 
                 if (num_survivors <= MIN_CLUSTERED) {
-                        bb_error_msg("num_survivors %d <= %d, not discarding more",
+                        VERB3 bb_error_msg("num_survivors %d <= %d, not discarding more",
                                         num_survivors, MIN_CLUSTERED);
                         break;
                 }
@@ -1381,8 +1382,8 @@ recv_and_process_peer_pkt(peer_t *p)
                  || errno == EAGAIN
                 ) {
 //TODO: always do this?
-                        set_next(p, retry_interval());
-                        goto close_sock;
+                        interval = retry_interval();
+                        goto set_next_and_close_sock;
                 }
                 xfunc_die();
         }
@@ -1407,7 +1408,7 @@ recv_and_process_peer_pkt(peer_t *p)
 // "RATE" - peer is overloaded, reduce polling freq
                 interval = poll_interval(0);
                 bb_error_msg("reply from %s: not synced, next query in %us", p->p_dotted, interval);
-                goto close_sock;
+                goto set_next_and_close_sock;
         }
 
 //      /* Verify valid root distance */
@@ -1466,18 +1467,30 @@ recv_and_process_peer_pkt(peer_t *p)
 
         p->reachable_bits |= 1;
         VERB1 {
-                bb_error_msg("reply from %s: reach 0x%02x offset %f delay %f",
+                bb_error_msg("reply from %s: reach 0x%02x offset %f delay %f status 0x%02x strat %d refid 0x%08x rootdelay %f",
                         p->p_dotted,
                         p->reachable_bits,
-                        datapoint->d_offset, p->lastpkt_delay);
+                        datapoint->d_offset,
+                        p->lastpkt_delay,
+                        p->lastpkt_status,
+                        p->lastpkt_stratum,
+                        p->lastpkt_refid,
+                        p->lastpkt_rootdelay
+                        /* not shown: m_ppoll, m_precision_exp, m_rootdisp,
+                         * m_reftime, m_orgtime, m_rectime, m_xmttime
+                         */
+                );
         }
 
         /* Muck with statictics and update the clock */
         filter_datapoints(p);
         q = select_and_cluster();
         rc = -1;
-        if (q)
-                rc = update_local_clock(q);
+        if (q) {
+                rc = 0;
+                if (!(option_mask32 & OPT_w))
+                        rc = update_local_clock(q);
+        }
 
         if (rc != 0) {
                 /* Adjust the poll interval by comparing the current offset
@@ -1537,9 +1550,9 @@ recv_and_process_peer_pkt(peer_t *p)
 
         /* Decide when to send new query for this peer */
         interval = poll_interval(0);
-        set_next(p, interval);
 
- close_sock:
+ set_next_and_close_sock:
+        set_next(p, interval);
         /* We do not expect any more packets from this peer for now.
          * Closing the socket informs kernel about it.
          * We open a new socket when we send a new query.
@@ -1723,7 +1736,7 @@ static NOINLINE void ntp_init(char **argv)
         opt_complementary = "dd:p::"; /* d: counter, p: list */
         opts = getopt32(argv,
                         "nqNx" /* compat */
-                        "p:"IF_FEATURE_NTPD_SERVER("l") /* NOT compat */
+                        "wp:"IF_FEATURE_NTPD_SERVER("l") /* NOT compat */
                         "d" /* compat */
                         "46aAbgL", /* compat, ignored */
                         &peers, &G.verbose);