389-ds-base/ldap/servers/slapd/rwlock.h

/** BEGIN COPYRIGHT BLOCK
 * This Program is free software; you can redistribute it and/or modify it under
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 * right to link the code of this Program with code not covered under the GNU
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 * Copyright (C) 2001 Sun Microsystems, Inc. Used by permission.
 * Copyright (C) 2005 Red Hat, Inc.
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 * END COPYRIGHT BLOCK **/

#ifdef HAVE_CONFIG_H
#  include <config.h>
#endif

#ifndef _RWLOCK_H_
#define _RWLOCK_H_

#include <prlock.h>
#include <prcvar.h>

typedef struct _rwl {
    PRLock	*rwl_readers_mutex;
    PRLock	*rwl_writers_mutex;
    PRCondVar	*rwl_writer_waiting_cv;
    int		rwl_num_readers;
    int		rwl_writer_waiting;

    int		(*rwl_acquire_read_lock)( struct _rwl * );
    int		(*rwl_relinquish_read_lock)( struct _rwl * );

    int		(*rwl_acquire_write_lock)( struct _rwl * );
    int		(*rwl_relinquish_write_lock)( struct _rwl * );
} rwl;

extern rwl *rwl_new();
extern void rwl_free( rwl **rh );
#endif /* _RWLOCK_H_ */