glibc/sysdeps/unix/sysv/linux/adjtime.c

71 lines
1.9 KiB
C

/* Copyright (C) 1995-2020 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, see
<https://www.gnu.org/licenses/>. */
#include <errno.h>
#include <limits.h>
#include <sys/time.h>
#include <sys/timex.h>
#define MAX_SEC (INT_MAX / 1000000L - 2)
#define MIN_SEC (INT_MIN / 1000000L + 2)
int
__adjtime (const struct timeval *itv, struct timeval *otv)
{
struct timex tntx;
if (itv)
{
struct timeval tmp;
/* We will do some check here. */
tmp.tv_sec = itv->tv_sec + itv->tv_usec / 1000000L;
tmp.tv_usec = itv->tv_usec % 1000000L;
if (tmp.tv_sec > MAX_SEC || tmp.tv_sec < MIN_SEC)
return INLINE_SYSCALL_ERROR_RETURN_VALUE (EINVAL);
tntx.offset = tmp.tv_usec + tmp.tv_sec * 1000000L;
tntx.modes = ADJ_OFFSET_SINGLESHOT;
}
else
tntx.modes = ADJ_OFFSET_SS_READ;
if (__glibc_unlikely (__adjtimex (&tntx) < 0))
return -1;
if (otv)
{
if (tntx.offset < 0)
{
otv->tv_usec = -(-tntx.offset % 1000000);
otv->tv_sec = -(-tntx.offset / 1000000);
}
else
{
otv->tv_usec = tntx.offset % 1000000;
otv->tv_sec = tntx.offset / 1000000;
}
}
return 0;
}
#ifdef VERSION_adjtime
weak_alias (__adjtime, __wadjtime);
default_symbol_version (__wadjtime, adjtime, VERSION_adjtime);
#else
weak_alias (__adjtime, adjtime)
#endif