Function IsEqualObject

ThirdParty/ASIO/common/combase.cpp:169–202

/* Compares two interfaces and returns TRUE if they are on the same object */

BOOL IsEqualObject(IUnknown *pFirst, IUnknown *pSecond)
{
    /*  Different objects can't have the same interface pointer for
        any interface
    */
    if (pFirst == pSecond) {
        return TRUE;
    }
    /*  OK - do it the hard way - check if they have the same
        IUnknown pointers - a single object can only have one of these
    */
    LPUNKNOWN pUnknown1;     // Retrieve the IUnknown interface
    LPUNKNOWN pUnknown2;     // Retrieve the other IUnknown interface
    HRESULT hr;              // General OLE return code

    ASSERT(pFirst);
    ASSERT(pSecond);

    /* See if the IUnknown pointers match */

    hr = pFirst->QueryInterface(IID_IUnknown,(void **) &pUnknown1);
    ASSERT(SUCCEEDED(hr));
    ASSERT(pUnknown1);

    hr = pSecond->QueryInterface(IID_IUnknown,(void **) &pUnknown2);
    ASSERT(SUCCEEDED(hr));
    ASSERT(pUnknown2);

    /* Release the extra interfaces we hold */

    pUnknown1->Release();
    pUnknown2->Release();
    return (pUnknown1 == pUnknown2);
}