shareablemutex.hxx

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#pragma once
 
#include <osl/interlck.h>
#include <osl/mutex.hxx>
 
namespace framework
{
 
class ShareableMutex
{
    public:
        ShareableMutex();
        ShareableMutex( const ShareableMutex& rShareableMutex );
        ShareableMutex& operator=( const ShareableMutex& rShareableMutex );
 
        ~ShareableMutex() { m_pMutexRef->release(); }
 
        void acquire();
        void release();
 
    private:
        /* ShareableMutex::MutexRef will destroy itself when the last ShareableMutex pointing to it is destroyed */
        struct MutexRef
        {
            MutexRef() : m_refCount(0) {}
            void acquire()
            {
                osl_atomic_increment( &m_refCount );
            }
 
            void release()
            {
                if ( osl_atomic_decrement( &m_refCount ) == 0 )
                    delete this;
            }
 
            oslInterlockedCount m_refCount;
            osl::Mutex          m_oslMutex;
        };
 
        MutexRef* m_pMutexRef;
};
 
class ShareGuard
{
    public:
        explicit ShareGuard( ShareableMutex& rShareMutex ) :
            m_rShareMutex( rShareMutex )
        {
            m_rShareMutex.acquire();
        }
 
        ~ShareGuard()
        {
            m_rShareMutex.release();
        }
 
    private:
        ShareGuard& operator=( const ShareGuard& ) = delete;
 
        ShareableMutex& m_rShareMutex;
};
 
}
 
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