|  | /* Low-level locking access to futex facilities.  Stub version. | 
|  | Copyright (C) 2014-2016 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 */ |