iokit/IOKit/IOSyncer.h

   1 /*
   2  * Copyright (c) 1998-2000 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_OSREFERENCE_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
  10  * License may not be used to create, or enable the creation or
  11  * redistribution of, unlawful or unlicensed copies of an Apple operating
  12  * system, or to circumvent, violate, or enable the circumvention or
  13  * violation of, any terms of an Apple operating system software license
  14  * agreement.
  15  *
  16  * Please obtain a copy of the License at
  17  * http://www.opensource.apple.com/apsl/ and read it before using this
  18  * file.
  19  *
  20  * The Original Code and all software distributed under the License are
  21  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  22  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  23  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  24  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  25  * Please see the License for the specific language governing rights and
  26  * limitations under the License.
  27  *
  28  * @APPLE_LICENSE_OSREFERENCE_HEADER_END@
  29  */
  30 #ifndef _IOSYNCER_H
  31 #define _IOSYNCER_H
  32
  33 #include <libkern/c++/OSObject.h>
  34 #include <IOKit/IOTypes.h>
  35 #include <IOKit/IOLocks.h>
  36
  37 class IOSyncer : public OSObject
  38 {
  39     OSDeclareDefaultStructors(IOSyncer)
  40
  41 private:
  42     // The spin lock that is used to guard the 'threadMustStop' variable.
  43     IOSimpleLock *guardLock;
  44     volatile bool threadMustStop;
  45     IOReturn fResult;
  46     virtual void free();
  47     virtual void privateSignal();
  48
  49 public:
  50
  51     static IOSyncer * create(bool twoRetains = true);
  52
  53     virtual bool init(bool twoRetains);
  54     virtual void reinit();
  55     virtual IOReturn wait(bool autoRelease = true);
  56     virtual void signal(IOReturn res = kIOReturnSuccess,
  57                                         bool autoRelease = true);
  58 };
  59
  60 #endif /* !_IOSYNCER */
  61