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/////////////////////////////////////////////////////////// 
// 
// CUnknown.cpp  
//   - Implementation of IUnknown base class 
// 
#include "CUnknown.h" 
#include "Util.h" 
 
static inline void trace(char* msg) 
	{Util::Trace("CUnknown", msg, S_OK) ;}  
static inline void trace(char* msg, HRESULT hr) 
	{Util::Trace("CUnknown", msg, hr) ;} 
 
/////////////////////////////////////////////////////////// 
// 
// Count of active objects 
//   - Use to determine if we can unload the DLL. 
// 
long CUnknown::s_cActiveComponents = 0 ; 
 
 
/////////////////////////////////////////////////////////// 
// 
// Constructor 
// 
CUnknown::CUnknown(IUnknown* pUnknownOuter) 
: m_cRef(1) 
{ 
	// Set m_pUnknownOuter pointer. 
	if (pUnknownOuter == NULL) 
	{ 
		trace("Not aggregating; delegate to nondelegating IUnknown.") ; 
		m_pUnknownOuter = reinterpret_cast 
		                     (static_cast 
		                     (this)) ;  // notice cast 
	} 
	else 
	{ 
		trace("Aggregating; delegate to outer IUnknown.") ; 
		m_pUnknownOuter = pUnknownOuter ; 
	} 
 
	// Increment count of active components. 
	::InterlockedIncrement(&s_cActiveComponents) ; 
} 
 
// 
// Destructor 
// 
CUnknown::~CUnknown() 
{ 
	InterlockedDecrement(&s_cActiveComponents) ; 
} 
 
// 
// FinalRelease - called by Release before it deletes the component 
// 
void CUnknown::FinalRelease() 
{ 
	trace("Increment reference count for final release.") ; 
	m_cRef = 1 ; 
} 
 
// 
// Nondelegating IUnknown 
//   - Override to handle custom interfaces. 
// 
HRESULT __stdcall  
	CUnknown::NondelegatingQueryInterface(const IID& iid, void** ppv) 
{ 
	// CUnknown supports only IUnknown. 
	if (iid == IID_IUnknown) 
	{ 
		return FinishQI(reinterpret_cast 
		                   (static_cast(this)), ppv) ; 
	}	 
	else 
	{ 
		*ppv = NULL ; 
		return E_NOINTERFACE ; 
	} 
} 
 
// 
// AddRef 
// 
ULONG __stdcall CUnknown::NondelegatingAddRef() 
{ 
	return ::InterlockedIncrement(&m_cRef) ; 
} 
 
// 
// Release 
// 
ULONG __stdcall CUnknown::NondelegatingRelease() 
{ 
	::InterlockedDecrement(&m_cRef) ; 
	if (m_cRef == 0) 
	{ 
		FinalRelease() ; 
		delete this ; 
		return 0 ; 
	} 
	return m_cRef ; 
} 
 
// 
// FinishQI 
//   - Helper function to simplify overriding 
//     NondelegatingQueryInterface 
// 
HRESULT CUnknown::FinishQI(IUnknown* pI, void** ppv)  
{ 
	*ppv = pI ; 
	pI->AddRef() ; 
	return S_OK ; 
}