with usig the meadian offset froma number of measurements the recording

of the last sensor update time got broken, doesn't show up with gps since
it updates often (more often than we read), but naddy ran into it with dcf.
record time of last sensor datum seperately. ok naddy balmer

src/usr.sbin/ntpd/ntpd.h

@@ -1,4 +1,4 @@
-/*	$OpenBSD: ntpd.h,v 1.78 2006/10/27 12:22:41 henning Exp $ */
+/*	$OpenBSD: ntpd.h,v 1.79 2006/11/20 20:58:47 henning Exp $ */
 
 /*
  * Copyright (c) 2003, 2004 Henning Brauer <henning@openbsd.org>
@@ -138,6 +138,7 @@ struct ntp_sensor {
 	struct ntp_offset		 offsets[SENSOR_OFFSETS];
 	struct ntp_offset		 update;
 	time_t				 next;
+	time_t				 last;
 	char				*device;
 	int				 sensorid;
 	u_int8_t			 weight;

src/usr.sbin/ntpd/sensors.c

@@ -1,4 +1,4 @@
-/*	$OpenBSD: sensors.c,v 1.25 2006/10/27 12:22:41 henning Exp $ */
+/*	$OpenBSD: sensors.c,v 1.26 2006/11/20 20:58:47 henning Exp $ */
 
 /*
  * Copyright (c) 2006 Henning Brauer <henning@openbsd.org>
@@ -156,9 +156,10 @@ sensor_query(struct ntp_sensor *s)
 		return;
 	}
 
-	if (sensor.tv.tv_sec == s->update.rcvd)	/* already seen */
+	if (sensor.tv.tv_sec == s->last)	/* already seen */
 		return;
 
+	s->last = sensor.tv.tv_sec;
 	memcpy(&refid, "HARD", sizeof(refid));
 	s->offsets[s->shift].offset = (0 - (float)sensor.value / 1000000000.0) -
 	    getoffset();