COM IUnknown接口封装

CAbstractUnknown.h

#include <objbase.h>
#include <unknwn.h>
#define DECLARE_IUNKNOWN_INTERFACE														\
	public:																				\
		virtual HRESULT _stdcall QueryInterface(const IID& riid,void** ppvObject);		\
		virtual ULONG _stdcall AddRef ();												\
		virtual ULONG _stdcall Release();
class CAbstractUnknown:public IUnknown
{
public:
	CAbstractUnknown();
	virtual HRESULT _stdcall QueryInterface(const IID& riid,void** ppvObject)=0;
    virtual ULONG _stdcall AddRef ();
	virtual ULONG _stdcall Release();
	//virtual HRESULT _stdcall NonDelegatingQueryInterface(const IID& riid,void** ppvObject)=0;
	//virtual ULONG _stdcall NonDelegatingAddRef();
	//virtual ULONG _stdcall NonDelegatingRelease();
protected:
	long m_ref;
	long g_components;
};
const CLSID CLSID_CAbstractUnknown={0x38dd17, 0x6420, 0x47ca, { 0x8b, 0xca, 0xbf, 0x8b, 0x4d, 0x21, 0x32, 0x87 } };
template<class I,const GUID* pGUID>I* interface_cast(IUnknown* pIUnknown)
{
	I* pi=NULL;
	HRESULT hr=pIUnknown->QueryInterface(*pGUID,(void**)&pi);
	assert(SUCCEEDED(hr));
	return pi;
}

 

CAbstractUnknown.cpp

#include "CAbstractUnknown.h"
CAbstractUnknown::CAbstractUnknown()
{
	m_ref=0;
	g_components=0;
}
/**
HRESULT _stdcall CAbstractUnknown::QueryInterface(const IID& riid,void** ppvObject)
{
	if(p_UnknownOuter!=NULL)
	{
		return p_UnknownOuter->QueryInterface(riid,ppvObject);
	}
	else
	{
		return NonDelegatingQueryInterface(riid,ppvObject);
	}
}*/
ULONG _stdcall CAbstractUnknown::AddRef()
{
	return InterlockedIncrement(&m_ref);
}
ULONG _stdcall CAbstractUnknown::Release()
{
	if(InterlockedDecrement(&m_ref)==0)
	{
		InterlockedDecrement(&g_components);
		delete this;
		return 0;
	}
	return m_ref;
}
/**
CAbstractUnknown::CAbstractUnknown(IUnknown* m_pUnknownouter)
{
	m_ref=1;
	InterlockedIncrement(&g_components);
	p_UnknownOuter=m_pUnknownouter;
}
HRESULT _stdcall CAbstractUnknown::NonDelegatingQueryInterface(const IID& riid,void** ppvObject)
{
	if(riid==IID_IUnknown)
	{
		*ppvObject=static_cast<INonDelegatingUnknown*>(this);
		((IUnknown*)(*ppvObject))->AddRef();
	}
	return S_OK;
}
ULONG _stdcall CAbstractUnknown::NonDelegatingAddRef()
{
	return InterlockedIncrement(&m_ref);
}
ULONG _stdcall CAbstractUnknown::NonDelegatingRelease()
{
	if(InterlockedDecrement(&m_ref)==0)
	{
		InterlockedDecrement(&g_components);
		delete this;
		return 0;
	}
	return m_ref;
}*/