From: Miroslav Lichvar <mlichvar@redhat.com>
Date: Tue, 24 Mar 2015 16:55:44 +0000 (+0100)
Subject: reference: don't report synchronized status during leap second
X-Git-Tag: 2.0-pre2~31
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=3f9691baffd0a061cc81a60be0eeaee430a9a710;p=thirdparty%2Fchrony.git

reference: don't report synchronized status during leap second

During inserted leap second the time is invalid, reply with
unsynchronized status to avoid confusing clients that are not smart
enough to ignore measurements close to leap second.
---

diff --git a/reference.c b/reference.c
index b5ac3352..4cb49d09 100644
--- a/reference.c
+++ b/reference.c
@@ -693,6 +693,9 @@ leap_start_timeout(void *arg)
   leap_in_progress = 1;
 
   switch (leap_mode) {
+    case REF_LeapModeSystem:
+      DEBUG_LOG(LOGF_Reference, "Waiting for system clock leap second correction");
+      break;
     case REF_LeapModeSlew:
       LCL_NotifyLeap(our_leap_sec);
       LCL_AccumulateOffset(our_leap_sec, 0.0);
@@ -731,11 +734,17 @@ set_leap_timeout(time_t now)
   if (!our_leap_sec)
     return;
 
-  /* Insert leap second at 0:00:00 UTC, delete at 23:59:59 UTC */
+  /* Insert leap second at 0:00:00 UTC, delete at 23:59:59 UTC.  If the clock
+     will be corrected by the system, timeout slightly sooner to be sure it
+     will happen before the system correction. */
   when.tv_sec = (now / (24 * 3600) + 1) * (24 * 3600);
   when.tv_usec = 0;
   if (our_leap_sec < 0)
     when.tv_sec--;
+  if (leap_mode == REF_LeapModeSystem) {
+    when.tv_sec--;
+    when.tv_usec = 500000;
+  }
 
   leap_timeout_id = SCH_AddTimeout(&when, leap_start_timeout, NULL);
   leap_timer_running = 1;
@@ -773,7 +782,7 @@ update_leap_status(NTP_Leap leap, time_t now, int reset)
     switch (leap_mode) {
       case REF_LeapModeSystem:
         LCL_SetSystemLeap(our_leap_sec);
-        break;
+        /* Fall through */
       case REF_LeapModeSlew:
       case REF_LeapModeStep:
       case REF_LeapModeIgnore:
@@ -1161,7 +1170,7 @@ REF_GetReferenceParams
     UTI_DiffTimevalsToDouble(&elapsed, local_time, &our_ref_time);
     extra_dispersion = (our_skew + fabs(our_residual_freq) + LCL_GetMaxClockError()) * elapsed;
 
-    *leap_status = our_leap_status;
+    *leap_status = !leap_in_progress ? our_leap_status : LEAP_Unsynchronised;
     *ref_id = our_ref_id;
     *ref_time = our_ref_time;
     *root_delay = our_root_delay;