glibc/sysdeps/unix/sysv/aix/gettimeofday.c
2002-08-28 21:26:20 +00:00

99 lines
2.7 KiB
C

/* Copyright (C) 1991,92,94,95,96,97,2001,2002 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library 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.
The GNU C Library 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 the GNU C Library; if not, write to the Free
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA. */
#include <errno.h>
#include <time.h>
#include <sys/time.h>
#ifndef HAVE_GNU_LD
# define __daylight daylight
# define __timezone timezone
# define __tzname tzname
#endif
#undef __gettimeofday
extern int rtc_upper (void);
extern int rtc_lower (void);
/* Assembler Routines to access the timer registers */
asm("\n\
.rtc_upper: mfspr 3,4 # copy RTCU to return register\n\
blr\n\
\n\
.rtc_lower: mfspr 3,5 # copy RTCL to return register\n\
blr\n\
");
/* Get the current time of day and timezone information,
putting it into *TV and *TZ. If TZ is NULL, *TZ is not filled.
Returns 0 on success, -1 on errors. */
int
__gettimeofday (tv, tz)
struct timeval *tv;
struct timezone *tz;
{
int ts, tl, tu;
if (tv == NULL)
{
__set_errno (EINVAL);
return -1;
}
ts = rtc_upper (); /* Seconds. */
tl = rtc_lower (); /* Nanoseconds. */
tu = rtc_upper (); /* Check for a carry from. */
if (ts != tu) /* The lower reg to the upper. */
tl = rtc_lower (); /* Recover from the race condition. */
tv->tv_sec = (long int) (tu + (double) tl / 1000000000);
tv->tv_usec = (long int) ((double) tl / 1000);
if (tz != NULL)
{
const time_t timer = tv->tv_sec;
struct tm tm;
const struct tm *tmp;
const long int save_timezone = __timezone;
const long int save_daylight = __daylight;
char *save_tzname[2];
save_tzname[0] = __tzname[0];
save_tzname[1] = __tzname[1];
tmp = localtime_r (&timer, &tm);
tz->tz_minuteswest = __timezone / 60;
tz->tz_dsttime = __daylight;
__timezone = save_timezone;
__daylight = save_daylight;
__tzname[0] = save_tzname[0];
__tzname[1] = save_tzname[1];
if (tmp == NULL)
return -1;
}
return 0;
}
INTDEF(__gettimeofday)
weak_alias (__gettimeofday, gettimeofday)