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/* Low-level locking access to futex facilities. Stub version.
Copyright (C) 2014-2017 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
<http://www.gnu.org/licenses/>. */
#ifndef _LOWLEVELLOCK_FUTEX_H
#define _LOWLEVELLOCK_FUTEX_H 1
#include <errno.h>
/* Values for 'private' parameter of locking macros. Note pthreadP.h
optimizes for these exact values, though they are not required. */
#define LLL_PRIVATE 0
#define LLL_SHARED 128
/* For most of these macros, the return value is never really used.
Nevertheless, the protocol is that each one returns a negated errno
code for failure or zero for success. (Note that the corresponding
Linux system calls can sometimes return positive values for success
cases too. We never use those values.) */
/* Wait while *FUTEXP == VAL for an lll_futex_wake call on FUTEXP. */
#define lll_futex_wait(futexp, val, private) \
lll_futex_timed_wait (futexp, val, NULL, private)
/* Wait until a lll_futex_wake call on FUTEXP, or TIMEOUT elapses. */
#define lll_futex_timed_wait(futexp, val, timeout, private) \
-ENOSYS
/* This macro should be defined only if FUTEX_CLOCK_REALTIME is also defined.
If CLOCKBIT is zero, this is identical to lll_futex_timed_wait.
If CLOCKBIT has FUTEX_CLOCK_REALTIME set, then it's the same but
TIMEOUT is counted by CLOCK_REALTIME rather than CLOCK_MONOTONIC. */
#define lll_futex_timed_wait_bitset(futexp, val, timeout, clockbit, private) \
-ENOSYS
/* Wake up up to NR waiters on FUTEXP. */
#define lll_futex_wake(futexp, nr, private) \
-ENOSYS
/* Wake up up to NR_WAKE waiters on FUTEXP. Move up to NR_MOVE of the
rest from waiting on FUTEXP to waiting on MUTEX (a different futex). */
#define lll_futex_requeue(futexp, nr_wake, nr_move, mutex, val, private) \
-ENOSYS
/* Wake up up to NR_WAKE waiters on FUTEXP and NR_WAKE2 on FUTEXP2. */
#define lll_futex_wake_unlock(futexp, nr_wake, nr_wake2, futexp2, private) \
-ENOSYS
/* Like lll_futex_wait (FUTEXP, VAL, PRIVATE) but with the expectation
that lll_futex_cmp_requeue_pi (FUTEXP, _, _, MUTEX, _, PRIVATE) will
be used to do the wakeup. Confers priority-inheritance behavior on
the waiter. */
#define lll_futex_wait_requeue_pi(futexp, val, mutex, private) \
lll_futex_timed_wait_requeue_pi (futexp, val, NULL, 0, mutex, private)
/* Like lll_futex_wait_requeue_pi, but with a timeout. */
#define lll_futex_timed_wait_requeue_pi(futexp, val, timeout, clockbit, \
mutex, private) \
-ENOSYS
/* Like lll_futex_requeue, but pairs with lll_futex_wait_requeue_pi
and inherits priority from the waiter. */
#define lll_futex_cmp_requeue_pi(futexp, nr_wake, nr_move, mutex, \
val, private) \
-ENOSYS
#endif /* lowlevellock-futex.h */
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