/*
* Copyright (c) 2001-2004 Jakub Jermar
* 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.
* - The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 THE AUTHOR 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.
*/
/** @addtogroup kernel_sync
* @{
*/
/** @file
*/
#ifndef KERN_WAITQ_H_
#define KERN_WAITQ_H_
#include <typedefs.h>
#include <synch/spinlock.h>
#include <abi/synch.h>
#include <adt/list.h>
/** Wait queue structure.
*
*/
typedef struct waitq {
/** Lock protecting wait queue structure.
*
* Must be acquired before T.lock for each T of type thread_t.
*/
IRQ_SPINLOCK_DECLARE(lock);
/**
* If negative, number of wakeups that are to be ignored (necessary for futex operation).
* If positive, number of wakeups that weren't able to wake a thread.
*/
int wakeup_balance;
/** List of sleeping threads for which there was no missed_wakeup. */
list_t sleepers;
bool closed;
} waitq_t;
typedef struct wait_guard {
ipl_t ipl;
} wait_guard_t;
struct thread;
extern void waitq_initialize(waitq_t *);
extern void waitq_initialize_with_count(waitq_t *, int);
extern errno_t waitq_sleep(waitq_t *);
extern errno_t _waitq_sleep_timeout(waitq_t *, uint32_t, unsigned int);
extern errno_t waitq_sleep_timeout(waitq_t *, uint32_t);
extern wait_guard_t waitq_sleep_prepare(waitq_t *);
extern errno_t waitq_sleep_unsafe(waitq_t *, wait_guard_t);
extern errno_t waitq_sleep_timeout_unsafe(waitq_t *, uint32_t, unsigned int, wait_guard_t);
extern void waitq_wake_one(waitq_t *);
extern void waitq_wake_all(waitq_t *);
extern void waitq_signal(waitq_t *);
extern void waitq_close(waitq_t *);
#endif
/** @}
*/