TRef.h

Go to the documentation of this file.

/********************************************************************
 *
 *  Project     Artec 3D Scanning SDK
 *
 *  Purpose:    Helper class for safe intefrace storage
 *
 *  Copyright:  Artec Group
 *
 ********************************************************************/

#ifndef _TREF_H_
#define _TREF_H_

#include <stddef.h>
#include <assert.h>
#include <artec/sdk/base/IRef.h>
#include <artec/sdk/base/Log.h>

namespace artec { namespace sdk { namespace base
{

template <class T> class TRef
{
public:
    typedef T base;

    TRef(T* p = NULL)
    {
        tObject_ = p;
        if (p)
            p->addRef();
    }

    TRef(const TRef<T>& p)
    {
        tObject_ = p.tObject_;

        if (tObject_)
            tObject_->addRef();
    }

    TRef(TRef<T>&& p)
    {
        tObject_ = p.tObject_;
        p.tObject_ = NULL;
    }

    ~TRef()
    {
        if (tObject_)
            tObject_->release();
    }

    operator bool() const { return tObject_ != NULL; }

    T* operator ->() const { assert( tObject_ != NULL ); return tObject_; }

    operator T*() const { return tObject_; }

    const T& operator *() const { assert( tObject_ != NULL ); return *tObject_; }

    T& operator *() { assert( tObject_ != NULL ); return *tObject_; }

    TRef<T>& operator=(T* p)
    {
        T* tmpObject = tObject_;

        tObject_ = p;

        if (tObject_)
            tObject_->addRef();

        if (tmpObject)
            tmpObject->release();

        return *this;
    }

    TRef<T>& operator=(const TRef<T>& p)
    {
        T* tmpObject = tObject_;

        tObject_ = p;

        if (tObject_)
            tObject_->addRef();

        if (tmpObject)
            tmpObject->release();

        return *this;
    }

    /// move operator
    TRef<T>& operator=(TRef<T>&& p)
    {
        // disable operator&() overloading
        void* addressP = reinterpret_cast<void*>(&const_cast<char&>(reinterpret_cast<const volatile char&>(p)));

        if (this != addressP)
        {
            if (tObject_)
                tObject_->release();

            tObject_ = p.tObject_;
            p.tObject_ = NULL;
        }
        return *this;
    }

    T** operator&()
    {
        if (tObject_ != NULL)
        {
            ABASESDK_ERROR(L"Please release your tref before using operator&");
            return NULL;
        }

        return &tObject_;
    }

    bool operator==(T* p) const
    {
        return tObject_ == p;
    }

    bool operator!=(T* p) const
    {
        return !(tObject_ == p);
    }

    /// attach to interface pointer without calling addref() for it
    void attach(T* p)
    {
        if (tObject_)
            tObject_->release();

        tObject_ = p;
    }

    /// detach interface pointer without calling release() for it
    T* detach()
    {
        T* tmpObject = tObject_;
        tObject_ = NULL;
        return tmpObject;
    }

    void release()
    {
        if (tObject_ == NULL)
            return;

        tObject_->release();
        tObject_ = NULL;
    }

protected:
    T* tObject_;

};

} } } // namespace artec::sdk::base

#endif // _TREF_H_