From: Miroslav Lichvar <mlichvar@redhat.com>
Date: Mon, 3 Jun 2013 09:34:15 +0000 (+0200)
Subject: Slew only non-zero local timestamps in ntp core
X-Git-Tag: 1.28-pre1~64
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=afceb9d24e855981b6fa5f7d4c7442e5f0caa5d6;p=thirdparty%2Fchrony.git

Slew only non-zero local timestamps in ntp core
---

diff --git a/ntp_core.c b/ntp_core.c
index eac5a19f..e9ef711c 100644
--- a/ntp_core.c
+++ b/ntp_core.c
@@ -1513,13 +1513,15 @@ NCR_SlewTimes(NCR_Instance inst, struct timeval *when, double dfreq, double doff
   struct timeval prev;
   double delta;
   prev = inst->local_rx;
-  UTI_AdjustTimeval(&inst->local_rx, when, &inst->local_rx, &delta, dfreq, doffset);
+  if (inst->local_rx.tv_sec || inst->local_rx.tv_usec)
+    UTI_AdjustTimeval(&inst->local_rx, when, &inst->local_rx, &delta, dfreq, doffset);
 #ifdef TRACEON
   LOG(LOGS_INFO, LOGF_NtpCore, "rx prev=[%s] new=[%s]",
       UTI_TimevalToString(&prev), UTI_TimevalToString(&inst->local_rx));
 #endif
   prev = inst->local_tx;
-  UTI_AdjustTimeval(&inst->local_tx, when, &inst->local_tx, &delta, dfreq, doffset);
+  if (inst->local_tx.tv_sec || inst->local_tx.tv_usec)
+    UTI_AdjustTimeval(&inst->local_tx, when, &inst->local_tx, &delta, dfreq, doffset);
 #ifdef TRACEON
   LOG(LOGS_INFO, LOGF_NtpCore, "tx prev=[%s] new=[%s]",
       UTI_TimevalToString(&prev), UTI_TimevalToString(&inst->local_tx));