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Diffstat (limited to 'libs/appleutility/CoreAudio/PublicUtility/CAMutex.h')
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diff --git a/libs/appleutility/CoreAudio/PublicUtility/CAMutex.h b/libs/appleutility/CoreAudio/PublicUtility/CAMutex.h new file mode 100644 index 0000000000..093066b400 --- /dev/null +++ b/libs/appleutility/CoreAudio/PublicUtility/CAMutex.h @@ -0,0 +1,163 @@ +/* + File: CAMutex.h + Abstract: Part of CoreAudio Utility Classes + Version: 1.1 + + Disclaimer: IMPORTANT: This Apple software is supplied to you by Apple + Inc. ("Apple") in consideration of your agreement to the following + terms, and your use, installation, modification or redistribution of + this Apple software constitutes acceptance of these terms. If you do + not agree with these terms, please do not use, install, modify or + redistribute this Apple software. + + In consideration of your agreement to abide by the following terms, and + subject to these terms, Apple grants you a personal, non-exclusive + license, under Apple's copyrights in this original Apple software (the + "Apple Software"), to use, reproduce, modify and redistribute the Apple + Software, with or without modifications, in source and/or binary forms; + provided that if you redistribute the Apple Software in its entirety and + without modifications, you must retain this notice and the following + text and disclaimers in all such redistributions of the Apple Software. + Neither the name, trademarks, service marks or logos of Apple Inc. may + be used to endorse or promote products derived from the Apple Software + without specific prior written permission from Apple. Except as + expressly stated in this notice, no other rights or licenses, express or + implied, are granted by Apple herein, including but not limited to any + patent rights that may be infringed by your derivative works or by other + works in which the Apple Software may be incorporated. + + The Apple Software is provided by Apple on an "AS IS" basis. APPLE + MAKES NO WARRANTIES, EXPRESS OR IMPLIED, INCLUDING WITHOUT LIMITATION + THE IMPLIED WARRANTIES OF NON-INFRINGEMENT, MERCHANTABILITY AND FITNESS + FOR A PARTICULAR PURPOSE, REGARDING THE APPLE SOFTWARE OR ITS USE AND + OPERATION ALONE OR IN COMBINATION WITH YOUR PRODUCTS. + + IN NO EVENT SHALL APPLE BE LIABLE FOR ANY SPECIAL, INDIRECT, INCIDENTAL + OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF + SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS + INTERRUPTION) ARISING IN ANY WAY OUT OF THE USE, REPRODUCTION, + MODIFICATION AND/OR DISTRIBUTION OF THE APPLE SOFTWARE, HOWEVER CAUSED + AND WHETHER UNDER THEORY OF CONTRACT, TORT (INCLUDING NEGLIGENCE), + STRICT LIABILITY OR OTHERWISE, EVEN IF APPLE HAS BEEN ADVISED OF THE + POSSIBILITY OF SUCH DAMAGE. + + Copyright (C) 2014 Apple Inc. All Rights Reserved. + +*/ +#ifndef __CAMutex_h__ +#define __CAMutex_h__ + +//================================================================================================== +// Includes +//================================================================================================== + +// System Includes +#if !defined(__COREAUDIO_USE_FLAT_INCLUDES__) + #include <CoreAudio/CoreAudioTypes.h> +#else + #include <CoreAudioTypes.h> +#endif + +#if TARGET_OS_MAC + #include <pthread.h> +#elif TARGET_OS_WIN32 + #include <windows.h> +#else + #error Unsupported operating system +#endif + +//================================================================================================== +// A recursive mutex. +//================================================================================================== + +class CAMutex +{ +// Construction/Destruction +public: + CAMutex(const char* inName); + virtual ~CAMutex(); + +// Actions +public: + virtual bool Lock(); + virtual void Unlock(); + virtual bool Try(bool& outWasLocked); // returns true if lock is free, false if not + + virtual bool IsFree() const; + virtual bool IsOwnedByCurrentThread() const; + +// Implementation +protected: + const char* mName; +#if TARGET_OS_MAC + pthread_t mOwner; + pthread_mutex_t mMutex; +#elif TARGET_OS_WIN32 + UInt32 mOwner; + HANDLE mMutex; +#endif + +// Helper class to manage taking and releasing recursively +public: + class Locker + { + + // Construction/Destruction + public: + Locker(CAMutex& inMutex) : mMutex(&inMutex), mNeedsRelease(false) { mNeedsRelease = mMutex->Lock(); } + Locker(CAMutex* inMutex) : mMutex(inMutex), mNeedsRelease(false) { mNeedsRelease = (mMutex != NULL && mMutex->Lock()); } + // in this case the mutex can be null + ~Locker() { if(mNeedsRelease) { mMutex->Unlock(); } } + + + private: + Locker(const Locker&); + Locker& operator=(const Locker&); + + // Implementation + private: + CAMutex* mMutex; + bool mNeedsRelease; + + }; + +// Unlocker + class Unlocker + { + public: + Unlocker(CAMutex& inMutex); + ~Unlocker(); + + private: + CAMutex& mMutex; + bool mNeedsLock; + + // Hidden definitions of copy ctor, assignment operator + Unlocker(const Unlocker& copy); // Not implemented + Unlocker& operator=(const Unlocker& copy); // Not implemented + }; + +// you can use this with Try - if you take the lock in try, pass in the outWasLocked var + class Tryer { + + // Construction/Destruction + public: + Tryer (CAMutex &mutex) : mMutex(mutex), mNeedsRelease(false), mHasLock(false) { mHasLock = mMutex.Try (mNeedsRelease); } + ~Tryer () { if (mNeedsRelease) mMutex.Unlock(); } + + bool HasLock () const { return mHasLock; } + + private: + Tryer(const Tryer&); + Tryer& operator=(const Tryer&); + + // Implementation + private: + CAMutex & mMutex; + bool mNeedsRelease; + bool mHasLock; + }; +}; + + +#endif // __CAMutex_h__ |