1/*
2 * Copyright (c) 2000-2007 Apple Inc. All rights reserved.
3 *
4 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
5 *
6 * This file contains Original Code and/or Modifications of Original Code
7 * as defined in and that are subject to the Apple Public Source License
8 * Version 2.0 (the 'License'). You may not use this file except in
9 * compliance with the License. The rights granted to you under the License
10 * may not be used to create, or enable the creation or redistribution of,
11 * unlawful or unlicensed copies of an Apple operating system, or to
12 * circumvent, violate, or enable the circumvention or violation of, any
13 * terms of an Apple operating system software license agreement.
14 *
15 * Please obtain a copy of the License at
16 * http://www.opensource.apple.com/apsl/ and read it before using this file.
17 *
18 * The Original Code and all software distributed under the License are
19 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
20 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
21 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
22 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
23 * Please see the License for the specific language governing rights and
24 * limitations under the License.
25 *
26 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
27 */
28/*
29 * @OSF_COPYRIGHT@
30 *
31 */
32/*
33 *	File:	kern/sync_sema.h
34 *	Author:	Joseph CaraDonna
35 *
36 *	Contains RT distributed semaphore synchronization service definitions.
37 */
38
39#ifndef _KERN_SYNC_SEMA_H_
40#define _KERN_SYNC_SEMA_H_
41
42#include <kern/kern_types.h>
43#include <mach/sync_policy.h>
44
45#ifdef MACH_KERNEL_PRIVATE
46
47#include <kern/queue.h>
48#include <kern/wait_queue.h>
49
50typedef struct semaphore {
51	queue_chain_t	  task_link;  /* chain of semaphores owned by a task */
52	struct wait_queue wait_queue; /* queue of blocked threads & lock     */
53	task_t		  owner;      /* task that owns semaphore            */
54	ipc_port_t	  port;	      /* semaphore port	 		     */
55	uint32_t	  ref_count;  /* reference count		     */
56	int		  count;      /* current count value	             */
57	boolean_t	  active;     /* active status			     */
58} Semaphore;
59
60#define semaphore_lock(semaphore)   wait_queue_lock(&(semaphore)->wait_queue)
61#define semaphore_unlock(semaphore) wait_queue_unlock(&(semaphore)->wait_queue)
62
63extern void semaphore_init(void);
64
65extern	void		semaphore_reference	(semaphore_t semaphore);
66extern	void		semaphore_dereference	(semaphore_t semaphore);
67
68#endif /* MACH_KERNEL_PRIVATE */
69
70#endif /* _KERN_SYNC_SEMA_H_ */
71