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//=--------------------------------------------------------------------------=
// StandardEnum.H
//=--------------------------------------------------------------------------=
// Copyright 1995 Microsoft Corporation. All Rights Reserved.
//
// THIS CODE AND INFORMATION IS PROVIDED "AS IS" WITHOUT WARRANTY OF
// ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING BUT NOT LIMITED TO
// THE IMPLIED WARRANTIES OF MERCHANTABILITY AND/OR FITNESS FOR A
// PARTICULAR PURPOSE.
//=--------------------------------------------------------------------------=
//
// object definition for a generic enumerator object.
//
#ifndef _STANDARDENUM_H_
// A specific implementation of the Clone function
void WINAPI CopyAndAddRefObject(void *pDest, const void *pSource, DWORD dwSize);
// An IEnumConnectionPoints creation function
HRESULT CreateInstance_IEnumConnectionPoints(LPENUMCONNECTIONPOINTS * ppEnum, DWORD count, ...);
// to support a generic Enumerator object, we'll just define this
// interface. it can be safely cast to any other enumerator, since all
// they differ in is their pointer type in Next().
//
class IEnumGeneric: public IUnknown {
public: virtual HRESULT __stdcall Next(ULONG celt, LPVOID rgelt, ULONG *pceltFetched) = 0; virtual HRESULT __stdcall Skip(ULONG celt) = 0; virtual HRESULT __stdcall Reset(void) = 0; virtual HRESULT __stdcall Clone(IEnumGeneric **ppenum) = 0;};
//=--------------------------------------------------------------------------=
// StandardEnum
//=--------------------------------------------------------------------------=
// a generic enumerator object. given a pointer to generic data, some
// information about the elements, and a function to copy the elements,
// we can implement a generic enumerator.
//
// NOTE: this class assumes that rgElements is HeapAlloc'd, and will free it
// in it's destructor [although it IS valid for this to be NULL if there
// are no elements to enumerate over.]
//
class CStandardEnum: public IEnumGeneric {
public: // IUnknown methods
//
STDMETHOD(QueryInterface)(REFIID riid, LPVOID * ppvObj); STDMETHOD_(ULONG,AddRef)(void); STDMETHOD_(ULONG,Release)(void);
// IEnumVariant methods
//
STDMETHOD(Next)(unsigned long celt, void * rgvar, unsigned long * pceltFetched); STDMETHOD(Skip)(unsigned long celt); STDMETHOD(Reset)(); STDMETHOD(Clone)(IEnumGeneric **ppEnumOut);
CStandardEnum(REFIID riid, BOOL fMembersAreInterfaces, int cElement, int cbElement, void *rgElements, void (WINAPI * pfnCopyElement)(void *, const void *, DWORD)); virtual ~CStandardEnum();
private: int m_cRef;
IID m_iid; // type of enumerator that we are
int m_cElements; // Total number of elements
int m_cbElementSize; // Size of each element
int m_iCurrent; // Current position: 0 = front, m_cElt = end
BOOL m_fMembersAreInterfaces; // Indicates that members of the enumerated array are
// Interfaces and that we need to hold refs on them
VOID * m_rgElements; // Array of elements
CStandardEnum *m_pEnumClonedFrom; // If we were cloned, from whom?
void (WINAPI * m_pfnCopyElement)(void *, const void *, DWORD);
const void *GetNthElement(int n) { return (const BYTE *)m_rgElements + (m_cbElementSize * n); }};
STDAPI_(void*) CStandardEnum_CreateInstance(REFIID riid, BOOL fMembersAreInterfaces, int cElement, int cbElement, void *rgElements, void (WINAPI * pfnCopyElement)(void *, const void *, DWORD));
#define _STANDARDENUM_H_
#endif // _STANDARDENUM_H_
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