osfmk/kern/sync_sema.h

   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,
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  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
  50 typedef 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
  63 extern void semaphore_init(void);
  64
  65 extern  void            semaphore_reference     (semaphore_t semaphore);
  66 extern  void            semaphore_dereference   (semaphore_t semaphore);
  67
  68 #endif /* MACH_KERNEL_PRIVATE */
  69
  70 #endif /* _KERN_SYNC_SEMA_H_ */