/usr/include/urcu/wfqueue.h is in liburcu-dev 0.6.7-2.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 | #ifndef _URCU_WFQUEUE_H
#define _URCU_WFQUEUE_H
/*
* wfqueue.h
*
* Userspace RCU library - Queue with Wait-Free Enqueue/Blocking Dequeue
*
* Copyright 2010 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
*
* This 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.
*
* This 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 this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include <pthread.h>
#include <assert.h>
#include <urcu/compiler.h>
#ifdef __cplusplus
extern "C" {
#endif
/*
* Queue with wait-free enqueue/blocking dequeue.
* This implementation adds a dummy head node when the queue is empty to ensure
* we can always update the queue locklessly.
*
* Inspired from half-wait-free/half-blocking queue implementation done by
* Paul E. McKenney.
*/
struct cds_wfq_node {
struct cds_wfq_node *next;
};
struct cds_wfq_queue {
struct cds_wfq_node *head, **tail;
struct cds_wfq_node dummy; /* Dummy node */
pthread_mutex_t lock;
};
#ifdef _LGPL_SOURCE
#include <urcu/static/wfqueue.h>
#define cds_wfq_node_init _cds_wfq_node_init
#define cds_wfq_init _cds_wfq_init
#define cds_wfq_enqueue _cds_wfq_enqueue
#define __cds_wfq_dequeue_blocking ___cds_wfq_dequeue_blocking
#define cds_wfq_dequeue_blocking _cds_wfq_dequeue_blocking
#else /* !_LGPL_SOURCE */
extern void cds_wfq_node_init(struct cds_wfq_node *node);
extern void cds_wfq_init(struct cds_wfq_queue *q);
extern void cds_wfq_enqueue(struct cds_wfq_queue *q, struct cds_wfq_node *node);
/* __cds_wfq_dequeue_blocking: caller ensures mutual exclusion between dequeues */
extern struct cds_wfq_node *__cds_wfq_dequeue_blocking(struct cds_wfq_queue *q);
extern struct cds_wfq_node *cds_wfq_dequeue_blocking(struct cds_wfq_queue *q);
#endif /* !_LGPL_SOURCE */
#ifdef __cplusplus
}
#endif
#endif /* _URCU_WFQUEUE_H */
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