xref: /xnu-11417.121.6/iokit/IOKit/IOConditionLock.h (revision a1e26a70f38d1d7daa7b49b258e2f8538ad81650)
1*a1e26a70SApple OSS Distributions /*
2*a1e26a70SApple OSS Distributions  * Copyright (c) 1998-2019 Apple Inc. All rights reserved.
3*a1e26a70SApple OSS Distributions  *
4*a1e26a70SApple OSS Distributions  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
5*a1e26a70SApple OSS Distributions  *
6*a1e26a70SApple OSS Distributions  * This file contains Original Code and/or Modifications of Original Code
7*a1e26a70SApple OSS Distributions  * as defined in and that are subject to the Apple Public Source License
8*a1e26a70SApple OSS Distributions  * Version 2.0 (the 'License'). You may not use this file except in
9*a1e26a70SApple OSS Distributions  * compliance with the License. The rights granted to you under the License
10*a1e26a70SApple OSS Distributions  * may not be used to create, or enable the creation or redistribution of,
11*a1e26a70SApple OSS Distributions  * unlawful or unlicensed copies of an Apple operating system, or to
12*a1e26a70SApple OSS Distributions  * circumvent, violate, or enable the circumvention or violation of, any
13*a1e26a70SApple OSS Distributions  * terms of an Apple operating system software license agreement.
14*a1e26a70SApple OSS Distributions  *
15*a1e26a70SApple OSS Distributions  * Please obtain a copy of the License at
16*a1e26a70SApple OSS Distributions  * http://www.opensource.apple.com/apsl/ and read it before using this file.
17*a1e26a70SApple OSS Distributions  *
18*a1e26a70SApple OSS Distributions  * The Original Code and all software distributed under the License are
19*a1e26a70SApple OSS Distributions  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
20*a1e26a70SApple OSS Distributions  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
21*a1e26a70SApple OSS Distributions  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
22*a1e26a70SApple OSS Distributions  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
23*a1e26a70SApple OSS Distributions  * Please see the License for the specific language governing rights and
24*a1e26a70SApple OSS Distributions  * limitations under the License.
25*a1e26a70SApple OSS Distributions  *
26*a1e26a70SApple OSS Distributions  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
27*a1e26a70SApple OSS Distributions  */
28*a1e26a70SApple OSS Distributions /* Copyright (c) 1999 Apple Computer, Inc.  All rights reserved.
29*a1e26a70SApple OSS Distributions  * Copyright (c) 1994-1996 NeXT Software, Inc.  All rights reserved.
30*a1e26a70SApple OSS Distributions  */
31*a1e26a70SApple OSS Distributions 
32*a1e26a70SApple OSS Distributions #ifndef _IOKIT_IOCONDITIONLOCK_H
33*a1e26a70SApple OSS Distributions #define _IOKIT_IOCONDITIONLOCK_H
34*a1e26a70SApple OSS Distributions 
35*a1e26a70SApple OSS Distributions #include <libkern/c++/OSPtr.h>
36*a1e26a70SApple OSS Distributions #include <libkern/c++/OSObject.h>
37*a1e26a70SApple OSS Distributions #include <IOKit/IOLib.h>
38*a1e26a70SApple OSS Distributions #include <IOKit/system.h>
39*a1e26a70SApple OSS Distributions 
40*a1e26a70SApple OSS Distributions #include <IOKit/IOLocks.h>
41*a1e26a70SApple OSS Distributions 
42*a1e26a70SApple OSS Distributions class IOConditionLock : public OSObject
43*a1e26a70SApple OSS Distributions {
44*a1e26a70SApple OSS Distributions 	OSDeclareDefaultStructors(IOConditionLock);
45*a1e26a70SApple OSS Distributions 
46*a1e26a70SApple OSS Distributions private:
47*a1e26a70SApple OSS Distributions 	IOLock *            cond_interlock;     // condition var Simple lock
48*a1e26a70SApple OSS Distributions 	volatile int        condition;
49*a1e26a70SApple OSS Distributions 
50*a1e26a70SApple OSS Distributions 	IOLock *            sleep_interlock;    // sleep lock Simple lock
51*a1e26a70SApple OSS Distributions 	unsigned char       interruptible;
52*a1e26a70SApple OSS Distributions 	volatile bool       want_lock;
53*a1e26a70SApple OSS Distributions 	volatile bool       waiting;
54*a1e26a70SApple OSS Distributions 
55*a1e26a70SApple OSS Distributions public:
56*a1e26a70SApple OSS Distributions 	static OSPtr<IOConditionLock> withCondition(int condition, bool inIntr = true);
57*a1e26a70SApple OSS Distributions 	virtual bool initWithCondition(int condition, bool inIntr = true);
58*a1e26a70SApple OSS Distributions 	virtual void free() APPLE_KEXT_OVERRIDE;
59*a1e26a70SApple OSS Distributions 
60*a1e26a70SApple OSS Distributions 	virtual bool tryLock(); // acquire lock, no waiting
61*a1e26a70SApple OSS Distributions 	virtual int  lock();    // acquire lock (enter critical section)
62*a1e26a70SApple OSS Distributions 	virtual void unlock();  // release lock (leave critical section)
63*a1e26a70SApple OSS Distributions 
64*a1e26a70SApple OSS Distributions 	virtual bool getInterruptible() const;
65*a1e26a70SApple OSS Distributions 	virtual int  getCondition() const;
66*a1e26a70SApple OSS Distributions 	virtual int  setCondition(int condition);
67*a1e26a70SApple OSS Distributions 
68*a1e26a70SApple OSS Distributions 	virtual int  lockWhen(int condition);// acquire lock when condition
69*a1e26a70SApple OSS Distributions 	virtual void unlockWith(int condition); // set condition & release lock
70*a1e26a70SApple OSS Distributions };
71*a1e26a70SApple OSS Distributions 
72*a1e26a70SApple OSS Distributions #endif /* _IOKIT_IOCONDITIONLOCK_H */
73