osfmk/kern/sync_sema.h

   1 /*
   2  * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * The contents of this file constitute Original Code as defined in and
   7  * are subject to the Apple Public Source License Version 1.1 (the
   8  * "License").  You may not use this file except in compliance with the
   9  * License.  Please obtain a copy of the License at
  10  * http://www.apple.com/publicsource and read it before using this file.
  11  *
  12  * This Original Code and all software distributed under the License are
  13  * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  14  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  15  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  16  * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
  17  * License for the specific language governing rights and limitations
  18  * under the License.
  19  *
  20  * @APPLE_LICENSE_HEADER_END@
  21  */
  22 /*
  23  * @OSF_COPYRIGHT@
  24  *
  25  */
  26 /*
  27  *      File:   kern/sync_sema.h
  28  *      Author: Joseph CaraDonna
  29  *
  30  *      Contains RT distributed semaphore synchronization service definitions.
  31  */
  32
  33 #ifndef _KERN_SYNC_SEMA_H_
  34 #define _KERN_SYNC_SEMA_H_
  35
  36 #include <kern/kern_types.h>
  37 #include <mach/sync_policy.h>
  38
  39 #ifdef MACH_KERNEL_PRIVATE
  40
  41 #include <kern/queue.h>
  42 #include <kern/lock.h>
  43 #include <kern/wait_queue.h>
  44
  45 typedef struct semaphore {
  46         queue_chain_t     task_link;  /* chain of semaphores owned by a task */
  47         struct wait_queue wait_queue; /* queue of blocked threads & lock     */
  48         task_t            owner;      /* task that owns semaphore            */
  49         ipc_port_t        port;       /* semaphore port                      */
  50         int               ref_count;  /* reference count                     */
  51         int               count;      /* current count value                 */
  52         boolean_t         active;     /* active status                       */
  53 } Semaphore;
  54
  55 #define semaphore_lock(semaphore)   wait_queue_lock(&(semaphore)->wait_queue)
  56 #define semaphore_unlock(semaphore) wait_queue_unlock(&(semaphore)->wait_queue)
  57
  58 extern void semaphore_init(void);
  59
  60 extern  void            semaphore_reference     (semaphore_t semaphore);
  61 extern  void            semaphore_dereference   (semaphore_t semaphore);
  62
  63 #endif /* MACH_KERNEL_PRIVATE */
  64
  65 #endif /* _KERN_SYNC_SEMA_H_ */