1/*
2 * Copyright (c) 1998-2019 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/* Copyright (c) 1999 Apple Computer, Inc. All rights reserved.
29 * Copyright (c) 1994-1996 NeXT Software, Inc. All rights reserved.
30 */
31
32#ifndef _IOKIT_IOCONDITIONLOCK_H
33#define _IOKIT_IOCONDITIONLOCK_H
34
35#include <libkern/c++/OSPtr.h>
36#include <libkern/c++/OSObject.h>
37#include <IOKit/IOLib.h>
38#include <IOKit/system.h>
39
40#include <IOKit/IOLocks.h>
41
42class IOConditionLock : public OSObject
43{
44 OSDeclareDefaultStructors(IOConditionLock);
45
46private:
47 IOLock * cond_interlock; // condition var Simple lock
48 volatile int condition;
49
50 IOLock * sleep_interlock; // sleep lock Simple lock
51 unsigned char interruptible;
52 volatile bool want_lock;
53 volatile bool waiting;
54
55public:
56 static OSPtr<IOConditionLock> withCondition(int condition, bool inIntr = true);
57 virtual bool initWithCondition(int condition, bool inIntr = true);
58 virtual void free() APPLE_KEXT_OVERRIDE;
59
60 virtual bool tryLock(); // acquire lock, no waiting
61 virtual int lock(); // acquire lock (enter critical section)
62 virtual void unlock(); // release lock (leave critical section)
63
64 virtual bool getInterruptible() const;
65 virtual int getCondition() const;
66 virtual int setCondition(int condition);
67
68 virtual int lockWhen(int condition);// acquire lock when condition
69 virtual void unlockWith(int condition); // set condition & release lock
70};
71
72#endif /* _IOKIT_IOCONDITIONLOCK_H */
73