/*
   Copyright (c) 2015 Anton Titov.

   Copyright (c) 2015 pCloud Ltd.  All rights reserved.

   Redistribution and use in source and binary forms, with or without
   modification, are permitted provided that the following conditions
   are met: Redistributions of source code must retain the above
   copyright notice, this list of conditions and the following
   disclaimer.  Redistributions in binary form must reproduce the
   above copyright notice, this list of conditions and the following
   disclaimer in the documentation and/or other materials provided
   with the distribution.  Neither the name of pCloud Ltd nor the
   names of its contributors may be used to endorse or promote
   products derived from this software without specific prior written
   permission.

   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
   FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL pCloud
   Ltd BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
   EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
   PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
   PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
   OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
   USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
   DAMAGE.
*/

#ifndef _PSYNC_LOCKS_H
#define _PSYNC_LOCKS_H

#include <pthread.h>

typedef struct {
  unsigned rcount;
  unsigned rwait;
  unsigned wcount;
  unsigned wwait;
  unsigned opts;
  pthread_key_t cntkey;
  pthread_mutex_t mutex;
  pthread_cond_t rcond;
  pthread_cond_t wcond;
} psync_rwlock_t;

void plocks_init(psync_rwlock_t *rw);
void plocks_destroy(psync_rwlock_t *rw);
void plocks_rdlock(psync_rwlock_t *rw);
int plocks_tryrdlock(psync_rwlock_t *rw);
int plocks_timedrdlock(psync_rwlock_t *rw, const struct timespec *abstime);
void plocks_rdlock_starvewr(psync_rwlock_t *rw);
void plocks_wrlock(psync_rwlock_t *rw);
int plocks_trywrlock(psync_rwlock_t *rw);
int plocks_timedwrlock(psync_rwlock_t *rw, const struct timespec *abstime);
void plocks_rslock(psync_rwlock_t *rw);
int plocks_towrlock(psync_rwlock_t *rw);
void plocks_unlock(psync_rwlock_t *rw);
unsigned plocks_num_waiters(psync_rwlock_t *rw);
int plocks_holding_rdlock(psync_rwlock_t *rw);
int plocks_holding_wrlock(psync_rwlock_t *rw);
int plocks_holding_lock(psync_rwlock_t *rw);

#endif