windows-xp/Source/XPSP1/NT/shell/cpls/plus/old_src/clssfact.cpp

//---------------------------------------------------------------------------
//
//      File: CLSSFACT.CPP
//
//      Implements a class factory object that creates CPropSheetExt objects.
//
//---------------------------------------------------------------------------

#include "precomp.hxx"
#pragma hdrstop


extern ULONG g_cObj;    // See PLUSTAB.CPP
extern ULONG g_cLock;   // See PLUSTAB.CPP


//---------------------------------------------------------------------------
//      ObjectDestroyed()
//
//      Function for the CPropSheetExt object to call when it is destroyed.
//      Because we're in a DLL, we only track the number of objects here,
//      letting DllCanUnloadNow take care of the rest.
//---------------------------------------------------------------------------
void FAR PASCAL ObjectDestroyed( void )
{
    g_cObj--;
    return;
}


//---------------------------------------------------------------------------
//      Class Member functions
//---------------------------------------------------------------------------

//---------------------------------------------------------------------------
//      Constructor
//---------------------------------------------------------------------------
CClassFactory::CClassFactory()
{
    m_cRef = 0L;
    return;
}

//---------------------------------------------------------------------------
//      Destructor
//---------------------------------------------------------------------------
CClassFactory::~CClassFactory( void )
{
    return;
}

//---------------------------------------------------------------------------
//      QueryInterface()
//---------------------------------------------------------------------------
STDMETHODIMP CClassFactory::QueryInterface( REFIID riid, LPVOID* ppv )
{
    *ppv = NULL;

    //Any interface on this object is the object pointer.
    if( IsEqualIID( riid, IID_IUnknown ) ||
        IsEqualIID( riid, IID_IClassFactory )
       )
    {
        *ppv = (LPVOID)this;
        ++m_cRef;
        return NOERROR;
    }

    return E_NOINTERFACE;
}

//---------------------------------------------------------------------------
//      AddRef()
//---------------------------------------------------------------------------
STDMETHODIMP_(ULONG) CClassFactory::AddRef()
{
    return ++m_cRef;
}

//---------------------------------------------------------------------------
//      Release()
//---------------------------------------------------------------------------
STDMETHODIMP_(ULONG) CClassFactory::Release()
{
    ULONG cRefT;

    cRefT = --m_cRef;

    if( 0L == m_cRef )
            delete this;

    return cRefT;
}

//---------------------------------------------------------------------------
//      CreateInstance()
//---------------------------------------------------------------------------
STDMETHODIMP
CClassFactory::CreateInstance( LPUNKNOWN pUnkOuter,
                               REFIID riid,
                               LPVOID FAR *ppvObj
                              )
{
    CPropSheetExt*  pObj;
    HRESULT         hr = E_OUTOFMEMORY;

    *ppvObj = NULL;

    // We don't support aggregation at all.
    if( pUnkOuter )
    {
        return CLASS_E_NOAGGREGATION;
    }

    //Verify that a controlling unknown asks for IShellPropSheetExt
    if( IsEqualIID( riid, IID_IShellPropSheetExt ) )
    {
        //Create the object, passing function to notify on destruction
        pObj = new CPropSheetExt( pUnkOuter, ObjectDestroyed );

        if( NULL == pObj )
        {
            return hr;
        }

        hr = pObj->QueryInterface( riid, ppvObj );

        //Kill the object if initial creation or FInit failed.
        if( FAILED(hr) )
        {
            delete pObj;
        }
        else
        {
            g_cObj++;
        }
        return hr;
    }

    return E_NOINTERFACE;
}

//---------------------------------------------------------------------------
//      LockServer()
//---------------------------------------------------------------------------
STDMETHODIMP CClassFactory::LockServer( BOOL fLock )
{
    if( fLock )
    {
        g_cLock++;
    }
    else
    {
        g_cLock--;
    }
    return NOERROR;
}