root/trunk/PublicUtility/CAMutex.h

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/*==================================================================================================
        CAMutex.h
        
==================================================================================================*/

#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
                
//      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() { if(mNeedsRelease) { mMutex.Unlock(); } }
        
        private:
                                        Locker(const Locker&);
                Locker&         operator=(const Locker&);
        
        //      Implementation
        private:
                CAMutex&        mMutex;
                bool            mNeedsRelease;
        
        };
};


#endif // __CAMutex_h__