From 8e82fb3308dc1329e72e280c26edca17859cf583 Mon Sep 17 00:00:00 2001
From: gdamore <gdamore@NetBSD.org>
Date: Thu, 7 Sep 2006 04:51:42 +0000
Subject: [PATCH] Eliminate the 2038 year check, because clock_ymdhms_to_sec
 already performs that check.  So instead, we test to make sure we have a
 non-negative second after the conversion.

While here, we also add a check to round the second counter up when setting
time if we are more than half-way into the second.
---
 sys/kern/kern_todr.c | 31 +++++++++++++++----------------
 1 file changed, 15 insertions(+), 16 deletions(-)

diff --git a/sys/kern/kern_todr.c b/sys/kern/kern_todr.c
index 652b7c1c260d..add7cea85a21 100644
--- a/sys/kern/kern_todr.c
+++ b/sys/kern/kern_todr.c
@@ -1,4 +1,4 @@
-/*	$NetBSD: kern_todr.c,v 1.9 2006/09/07 04:24:26 gdamore Exp $	*/
+/*	$NetBSD: kern_todr.c,v 1.10 2006/09/07 04:51:42 gdamore Exp $	*/
 
 /*
  * Copyright (c) 1992, 1993
@@ -76,7 +76,7 @@
  *	@(#)clock.c	8.1 (Berkeley) 6/10/93
  */
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: kern_todr.c,v 1.9 2006/09/07 04:24:26 gdamore Exp $");
+__KERNEL_RCSID(0, "$NetBSD: kern_todr.c,v 1.10 2006/09/07 04:51:42 gdamore Exp $");
 
 #include <sys/param.h>
 
@@ -257,20 +257,16 @@ todr_gettime(todr_chip_handle_t tch, struct timeval *tvp)
 	if (tch->todr_gettime_ymdhms) {
 		if ((rv = tch->todr_gettime_ymdhms(tch, &dt)) != 0)	
 			return rv;
+
 		/*
-		 * If tv_sec is 32 bits, then the "End of Time" is Mon
-		 * Jan 18 22:14:07 2038 (US/Eastern) This code copes
-		 * with RTC's past the end of time if tv_sec is an
-		 * int32 or less. Needed because sometimes RTCs screw
-		 * up or are badly set, and that would cause the time
-		 * to go negative in the calculation below, which
-		 * causes Very Bad Mojo. This at least lets the user
-		 * boot and fix the problem.  Note the code is self
-		 * eliminating once tv_sec goes to 64 bits.
+		 * Formerly we had code here that explicitly checked
+		 * for 2038 year rollover.
+		 *
+		 * However, clock_ymdhms_to_secs performs the same
+		 * check for us, so we need not worry about it.  Note
+		 * that this assumes that the tvp->tv_sec member is is
+		 * a time_t.
 		 */
-		if (/* CONSTCOND */ sizeof(tvp->tv_sec) <= sizeof(int32_t))
-			if (dt.dt_year >= 2038)
-				return -1;
 
 		/* simple sanity checks */
 		if (dt.dt_mon > 12 || dt.dt_day > 31 ||
@@ -279,7 +275,7 @@ todr_gettime(todr_chip_handle_t tch, struct timeval *tvp)
 
 		tvp->tv_sec = clock_ymdhms_to_secs(&dt) + rtc_offset * 60;
 		tvp->tv_usec = 0;
-		return 0;
+		return tvp->tv_sec < 0 ? -1 : 0;
 	}
 
 	return -1;
@@ -294,7 +290,10 @@ todr_settime(todr_chip_handle_t tch, volatile struct timeval *tvp)
 		return tch->todr_settime(tch, tvp);
 
 	if (tch->todr_settime_ymdhms) {
-		clock_secs_to_ymdhms(tvp->tv_sec - rtc_offset * 60, &dt);
+		time_t	sec = tvp->tv_sec - rtc_offset * 60;
+		if (tvp->tv_usec >= 500000)
+			sec++;
+		clock_secs_to_ymdhms(sec, &dt);
 		return tch->todr_settime_ymdhms(tch, &dt);
 	}