2 * Copyright (c) 1988 University of Utah.
3 * Copyright (c) 1982, 1990, 1993
4 * The Regents of the University of California. All rights reserved.
6 * This code is derived from software contributed to Berkeley by
7 * the Systems Programming Group of the University of Utah Computer
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 * 4. Neither the name of the University nor the names of its contributors
19 * may be used to endorse or promote products derived from this software
20 * without specific prior written permission.
22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34 * from: Utah $Hdr: clock.c 1.18 91/01/21$
35 * from: @(#)clock.c 8.2 (Berkeley) 1/12/94
36 * from: NetBSD: clock_subr.c,v 1.6 2001/07/07 17:04:02 thorpej Exp
38 * from: src/sys/i386/isa/clock.c,v 1.176 2001/09/04
41 #include <sys/cdefs.h>
42 __FBSDID("$FreeBSD$");
44 #include <sys/param.h>
45 #include <sys/systm.h>
46 #include <sys/kernel.h>
48 #include <sys/clock.h>
49 #include <sys/sysctl.h>
50 #include <sys/timetc.h>
52 static int adjkerntz; /* local offset from GMT in seconds */
53 static int wall_cmos_clock; /* wall CMOS clock assumed if != 0 */
54 int disable_rtc_set; /* disable resettodr() if != 0 */
60 * These have traditionally been in machdep, but should probably be moved to
63 SYSCTL_INT(_machdep, OID_AUTO, disable_rtc_set,
64 CTLFLAG_RW, &disable_rtc_set, 0, "");
66 SYSCTL_INT(_machdep, OID_AUTO, wall_cmos_clock,
67 CTLFLAG_RW, &wall_cmos_clock, 0, "");
70 sysctl_machdep_adjkerntz(SYSCTL_HANDLER_ARGS)
73 error = sysctl_handle_int(oidp, oidp->oid_arg1, oidp->oid_arg2,
75 if (!error && req->newptr)
80 SYSCTL_PROC(_machdep, OID_AUTO, adjkerntz, CTLTYPE_INT|CTLFLAG_RW,
81 &adjkerntz, 0, sysctl_machdep_adjkerntz, "I", "");
83 /*--------------------------------------------------------------------*
84 * Generic routines to convert between a POSIX date
85 * (seconds since 1/1/1970) and yr/mo/day/hr/min/sec
86 * Derived from NetBSD arch/hp300/hp300/clock.c
91 #define days_in_year(y) (leapyear(y) ? 366 : 365)
92 #define days_in_month(y, m) \
93 (month_days[(m) - 1] + (m == FEBRUARY ? leapyear(y) : 0))
94 /* Day of week. Days are counted from 1/1/1970, which was a Thursday */
95 #define day_of_week(days) (((days) + 4) % 7)
97 static const int month_days[12] = {
98 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31
103 * This inline avoids some unnecessary modulo operations
104 * as compared with the usual macro:
105 * ( ((year % 4) == 0 &&
106 * (year % 100) != 0) ||
107 * ((year % 400) == 0) )
108 * It is otherwise equivalent.
115 if ((year & 3) == 0) {
117 if ((year % 100) == 0) {
119 if ((year % 400) == 0)
127 clock_ct_to_ts(struct clocktime *ct, struct timespec *ts)
135 if (ct->mon < 1 || ct->mon > 12 || ct->day < 1 ||
136 ct->day > days_in_month(year, ct->mon) ||
137 ct->hour > 23 || ct->min > 59 || ct->sec > 59 ||
138 ct->year > 2037) /* time_t overflow */
142 * Compute days since start of time
143 * First from years, then from months.
146 for (i = POSIX_BASE_YEAR; i < year; i++)
147 days += days_in_year(i);
150 for (i = 1; i < ct->mon; i++)
151 days += days_in_month(year, i);
152 days += (ct->day - 1);
154 /* Another sanity check. */
155 if (ct->dow != -1 && ct->dow != day_of_week(days))
158 /* Add hours, minutes, seconds. */
159 secs = ((days * 24 + ct->hour) * 60 + ct->min) * 60 + ct->sec;
162 ts->tv_nsec = ct->nsec;
167 clock_ts_to_ct(struct timespec *ts, struct clocktime *ct)
170 time_t rsec; /* remainder seconds */
174 days = secs / SECDAY;
175 rsec = secs % SECDAY;
177 ct->dow = day_of_week(days);
179 /* Subtract out whole years, counting them in i. */
180 for (year = POSIX_BASE_YEAR; days >= days_in_year(year); year++)
181 days -= days_in_year(year);
184 /* Subtract out whole months, counting them in i. */
185 for (i = 1; days >= days_in_month(year, i); i++)
186 days -= days_in_month(year, i);
189 /* Days are what is left over (+1) from all that. */
192 /* Hours, minutes, seconds are easy */
193 ct->hour = rsec / 3600;
198 ct->nsec = ts->tv_nsec;
205 return (tz_minuteswest * 60 + (wall_cmos_clock ? adjkerntz : 0));