67fb4482ac
Partially revert 2b3c81b02f, which
tried to avoid inconsistent rules about when and how to create the
/dev/rtc symlink.
Instead of conditionally or not creating the /dev/rtc link at all,
now always create it with additional and more reliable udev rules.
First try to find the "system rtc" with the hctosys flag, if this
is not found, fall back to create the link for /dev/rtc0.
Our code now never actively searches for the "system rtc" it can
always use /dev/rtc.
161 lines
4.1 KiB
C
161 lines
4.1 KiB
C
/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
|
|
|
|
/***
|
|
This file is part of systemd.
|
|
|
|
Copyright 2010-2012 Lennart Poettering
|
|
|
|
systemd is free software; you can redistribute it and/or modify it
|
|
under the terms of the GNU Lesser General Public License as published by
|
|
the Free Software Foundation; either version 2.1 of the License, or
|
|
(at your option) any later version.
|
|
|
|
systemd is distributed in the hope that it will be useful, but
|
|
WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
|
Lesser General Public License for more details.
|
|
|
|
You should have received a copy of the GNU Lesser General Public License
|
|
along with systemd; If not, see <http://www.gnu.org/licenses/>.
|
|
***/
|
|
|
|
#include <assert.h>
|
|
#include <string.h>
|
|
#include <unistd.h>
|
|
#include <errno.h>
|
|
#include <stdlib.h>
|
|
#include <signal.h>
|
|
#include <stdio.h>
|
|
#include <sys/types.h>
|
|
#include <sys/stat.h>
|
|
#include <fcntl.h>
|
|
#include <sys/ioctl.h>
|
|
#include <stdarg.h>
|
|
#include <ctype.h>
|
|
#include <sys/prctl.h>
|
|
#include <sys/time.h>
|
|
#include <linux/rtc.h>
|
|
|
|
#include "macro.h"
|
|
#include "util.h"
|
|
#include "log.h"
|
|
#include "strv.h"
|
|
#include "hwclock.h"
|
|
#include "fileio.h"
|
|
|
|
int hwclock_get_time(struct tm *tm) {
|
|
int fd;
|
|
int err = 0;
|
|
|
|
assert(tm);
|
|
|
|
fd = open("/dev/rtc", O_RDONLY|O_CLOEXEC);
|
|
if (fd < 0)
|
|
return -errno;
|
|
|
|
/* This leaves the timezone fields of struct tm
|
|
* uninitialized! */
|
|
if (ioctl(fd, RTC_RD_TIME, tm) < 0)
|
|
err = -errno;
|
|
|
|
/* We don't know daylight saving, so we reset this in order not
|
|
* to confused mktime(). */
|
|
tm->tm_isdst = -1;
|
|
|
|
close_nointr_nofail(fd);
|
|
|
|
return err;
|
|
}
|
|
|
|
int hwclock_set_time(const struct tm *tm) {
|
|
int fd;
|
|
int err = 0;
|
|
|
|
assert(tm);
|
|
|
|
fd = open("/dev/rtc", O_RDONLY|O_CLOEXEC);
|
|
if (fd < 0)
|
|
return -errno;
|
|
|
|
if (ioctl(fd, RTC_SET_TIME, tm) < 0)
|
|
err = -errno;
|
|
|
|
close_nointr_nofail(fd);
|
|
|
|
return err;
|
|
}
|
|
|
|
int hwclock_is_localtime(void) {
|
|
_cleanup_fclose_ FILE *f;
|
|
|
|
/*
|
|
* The third line of adjtime is "UTC" or "LOCAL" or nothing.
|
|
* # /etc/adjtime
|
|
* 0.0 0 0
|
|
* 0
|
|
* UTC
|
|
*/
|
|
f = fopen("/etc/adjtime", "re");
|
|
if (f) {
|
|
char line[LINE_MAX];
|
|
bool b;
|
|
|
|
b = fgets(line, sizeof(line), f) &&
|
|
fgets(line, sizeof(line), f) &&
|
|
fgets(line, sizeof(line), f);
|
|
if (!b)
|
|
return -EIO;
|
|
|
|
truncate_nl(line);
|
|
return streq(line, "LOCAL");
|
|
|
|
} else if (errno != ENOENT)
|
|
return -errno;
|
|
|
|
return 0;
|
|
}
|
|
|
|
int hwclock_set_timezone(int *min) {
|
|
const struct timeval *tv_null = NULL;
|
|
struct timespec ts;
|
|
struct tm *tm;
|
|
int minutesdelta;
|
|
struct timezone tz;
|
|
|
|
assert_se(clock_gettime(CLOCK_REALTIME, &ts) == 0);
|
|
assert_se(tm = localtime(&ts.tv_sec));
|
|
minutesdelta = tm->tm_gmtoff / 60;
|
|
|
|
tz.tz_minuteswest = -minutesdelta;
|
|
tz.tz_dsttime = 0; /* DST_NONE*/
|
|
|
|
/*
|
|
* If the hardware clock does not run in UTC, but in local time:
|
|
* The very first time we set the kernel's timezone, it will warp
|
|
* the clock so that it runs in UTC instead of local time.
|
|
*/
|
|
if (settimeofday(tv_null, &tz) < 0)
|
|
return -errno;
|
|
if (min)
|
|
*min = minutesdelta;
|
|
return 0;
|
|
}
|
|
|
|
int hwclock_reset_timezone(void) {
|
|
const struct timeval *tv_null = NULL;
|
|
struct timezone tz;
|
|
|
|
tz.tz_minuteswest = 0;
|
|
tz.tz_dsttime = 0; /* DST_NONE*/
|
|
|
|
/*
|
|
* The very first time we set the kernel's timezone, it will warp
|
|
* the clock. Do a dummy call here, so the time warping is sealed
|
|
* and we set only the time zone with next call.
|
|
*/
|
|
if (settimeofday(tv_null, &tz) < 0)
|
|
return -errno;
|
|
|
|
return 0;
|
|
}
|