[src/trunk]: src/etc Add a new /etc/rc.conf option: rtclocaltime=YES adapts t...

[martin <martin%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/3617638fed85
branches:  trunk
changeset: 556777:3617638fed85
user:      martin <martin%NetBSD.org@localhost>
date:      Sat Dec 27 00:23:22 2003 +0000

description:
Add a new /etc/rc.conf option: rtclocaltime=YES adapts the RTC offset
at boot automatically, so a machine dual booting another OS that uses
the RTC at localtime and NetBSD agree on the current time even if daylight
saving started/ended (without recompiling a kernel twice per year).
Awk code by Matt Thomas.

diffstat:

 etc/defaults/rc.conf  |   6 +++++-
 etc/rc.d/rtclocaltime |  33 +++++++++++++++++++++++++++++++++
 2 files changed, 38 insertions(+), 1 deletions(-)

diffs (57 lines):

diff -r d3d021261cbe -r 3617638fed85 etc/defaults/rc.conf
--- a/etc/defaults/rc.conf      Sat Dec 27 00:05:46 2003 +0000
+++ b/etc/defaults/rc.conf      Sat Dec 27 00:23:22 2003 +0000
@@ -1,4 +1,4 @@
-#      $NetBSD: rc.conf,v 1.51 2003/10/20 15:02:15 christos Exp $
+#      $NetBSD: rc.conf,v 1.52 2003/12/27 00:23:22 martin Exp $
 #
 # /etc/defaults/rc.conf --
 #      default configuration of /etc/rc.conf
@@ -105,6 +105,10 @@
 accounting=NO                                  # uses /var/account/acct
 newsyslog=NO           newsyslog_flags=""      # trim log files
 
+# cope with other OSes using the real time clock at localtime on this
+# machine (by adjusting kern.rtc_offset at boot)
+rtclocaltime=NO
+
 # NOTE: default coredump name now set in /etc/sysctl.conf
 
 #
diff -r d3d021261cbe -r 3617638fed85 etc/rc.d/rtclocaltime
--- /dev/null   Thu Jan 01 00:00:00 1970 +0000
+++ b/etc/rc.d/rtclocaltime     Sat Dec 27 00:23:22 2003 +0000
@@ -0,0 +1,33 @@
+#! /bin/sh
+
+# PROVIDE: rtclocaltime
+# REQUIRE: mountcritremote
+# BEFORE:  ntpdate ntpd
+
+. /etc/rc.subr
+
+name="rtclocaltime"
+rcvar=$name
+start_cmd="rtclocaltime_start"
+stop_cmd=":"
+
+rtclocaltime_start()
+{
+       rtcoff=$(date '+%z' | awk '{
+               offset = int($1);
+               if (offset < 0) {
+                       sign = -1;
+                       offset = -offset;
+               } else {
+                       sign = 1;
+               }
+               minutes = offset % 100;
+               hours = offset / 100;
+               offset = sign * (hours * 60 + minutes);
+               print offset;
+       }')
+       sysctl -w kern.rtc_offset=$((-1 * $rtcoff))
+}
+
+load_rc_config $name
+run_rc_command "$1"