glibc/nptl/lll_timedlock_wait.c

63 lines
1.9 KiB
C

/* Timed low level locking for pthread library. Generic futex-using version.
Copyright (C) 2003-2020 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Paul Mackerras <paulus@au.ibm.com>, 2003.
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 <atomic.h>
#include <errno.h>
#include <lowlevellock.h>
#include <sys/time.h>
#include <time.h>
int
__lll_clocklock_wait (int *futex, int val, clockid_t clockid,
const struct timespec *abstime, int private)
{
struct timespec ts, *tsp = NULL;
if (abstime != NULL)
{
/* Reject invalid timeouts. */
if (! valid_nanoseconds (abstime->tv_nsec))
return EINVAL;
/* Get the current time. This can only fail if clockid is not valid. */
if (__glibc_unlikely (__clock_gettime (clockid, &ts) != 0))
return EINVAL;
/* Compute relative timeout. */
ts.tv_sec = abstime->tv_sec - ts.tv_sec;
ts.tv_nsec = abstime->tv_nsec - ts.tv_nsec;
if (ts.tv_nsec < 0)
{
ts.tv_nsec += 1000000000;
--ts.tv_sec;
}
if (ts.tv_sec < 0)
return ETIMEDOUT;
tsp = &ts;
}
/* If *futex == val, wait until woken or timeout. */
lll_futex_timed_wait (futex, val, tsp, private);
return 0;
}