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

88 lines
2.1 KiB
C

/* time -- Get number of seconds since Epoch. Linux version.
Copyright (C) 2020-2023 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/>. */
/* Optimize the function call by setting the PLT directly to vDSO symbol. */
#ifdef USE_IFUNC_TIME
# include <time.h>
# include <sysdep.h>
# include <sysdep-vdso.h>
#ifdef SHARED
# include <dl-vdso.h>
# include <libc-vdso.h>
static time_t
time_syscall (time_t *t)
{
return INLINE_SYSCALL_CALL (time, t);
}
# undef INIT_ARCH
# define INIT_ARCH() \
void *vdso_time = dl_vdso_vsym (HAVE_TIME_VSYSCALL);
libc_ifunc (time,
vdso_time ? VDSO_IFUNC_RET (vdso_time)
: (void *) time_syscall);
# else
time_t
time (time_t *t)
{
return INLINE_VSYSCALL (time, 1, t);
}
# endif /* !SHARED */
#else /* USE_IFUNC_TIME */
# include <time.h>
# include <time-clockid.h>
# include <errno.h>
/* Return the time now, and store it in *TIMER if not NULL. */
__time64_t
__time64 (__time64_t *timer)
{
struct __timespec64 ts;
__clock_gettime64 (TIME_CLOCK_GETTIME_CLOCKID, &ts);
if (timer != NULL)
*timer = ts.tv_sec;
return ts.tv_sec;
}
# if __TIMESIZE != 64
libc_hidden_def (__time64)
time_t
__time (time_t *timer)
{
__time64_t t = __time64 (NULL);
if (! in_time_t_range (t))
{
__set_errno (EOVERFLOW);
return -1;
}
if (timer != NULL)
*timer = t;
return t;
}
# endif
weak_alias (__time, time)
#endif