windows-nt/Source/XPSP1/NT/admin/wmi/wbem/scripting/methvar.cpp
2020-09-26 16:20:57 +08:00

316 lines
6.3 KiB
C++

//***************************************************************************
//
// Copyright (c) 1998-1999 Microsoft Corporation
//
// METHVAR.CPP
//
// alanbos 15-Aug-96 Created.
//
// Defines implementation of IEnumVARIANT for iterators of ISWbemMethodSet
//
//***************************************************************************
#include "precomp.h"
//***************************************************************************
//
// CMethodSetEnumVar::CMethodSetEnumVar
//
// DESCRIPTION:
//
// Constructor.
//
//***************************************************************************
CMethodSetEnumVar::CMethodSetEnumVar(CSWbemMethodSet *pMethodSet,
ULONG initialPos)
{
m_cRef = 0;
m_pos = 0;
m_pMethodSet = pMethodSet;
m_pMethodSet->AddRef ();
InterlockedIncrement(&g_cObj);
}
//***************************************************************************
//
// CMethodSetEnumVar::~CMethodSetEnumVar
//
// DESCRIPTION:
//
// Destructor.
//
//***************************************************************************
CMethodSetEnumVar::~CMethodSetEnumVar(void)
{
InterlockedDecrement(&g_cObj);
if (m_pMethodSet)
m_pMethodSet->Release ();
}
//***************************************************************************
// HRESULT CMethodSetEnumVar::QueryInterface
// long CMethodSetEnumVar::AddRef
// long CMethodSetEnumVar::Release
//
// DESCRIPTION:
//
// Standard Com IUNKNOWN functions.
//
//***************************************************************************
STDMETHODIMP CMethodSetEnumVar::QueryInterface (
IN REFIID riid,
OUT LPVOID *ppv
)
{
*ppv=NULL;
if (IID_IUnknown==riid || IID_IEnumVARIANT==riid)
*ppv=this;
if (NULL!=*ppv)
{
((LPUNKNOWN)*ppv)->AddRef();
return NOERROR;
}
return ResultFromScode(E_NOINTERFACE);
}
STDMETHODIMP_(ULONG) CMethodSetEnumVar::AddRef(void)
{
InterlockedIncrement(&m_cRef);
return m_cRef;
}
STDMETHODIMP_(ULONG) CMethodSetEnumVar::Release(void)
{
InterlockedDecrement(&m_cRef);
if (0L!=m_cRef)
return m_cRef;
delete this;
return 0;
}
//***************************************************************************
//
// SCODE CMethodSetEnumVar::Reset
//
// DESCRIPTION:
//
// Reset the enumeration
//
// PARAMETERS:
//
// RETURN VALUES:
//
// S_OK success
//
//***************************************************************************
HRESULT CMethodSetEnumVar::Reset ()
{
m_pos = 0;
return S_OK;
}
//***************************************************************************
//
// SCODE CMethodSetEnumVar::Next
//
// DESCRIPTION:
//
// Get the next object in the enumeration
//
// PARAMETERS:
//
//
// RETURN VALUES:
//
// S_OK success (all requested elements returned)
// S_FALSE otherwise
//
//***************************************************************************
HRESULT CMethodSetEnumVar::Next (
ULONG cElements,
VARIANT FAR* pVar,
ULONG FAR* pcElementFetched
)
{
HRESULT hr = S_OK;
ULONG l2 = 0;
if (NULL != pcElementFetched)
*pcElementFetched = 0;
if (NULL != pVar)
{
for (ULONG l = 0; l < cElements; l++)
VariantInit (&pVar [l]);
if (m_pMethodSet)
{
// Retrieve the next cElements elements.
if (SeekCurrentPosition ())
{
for (l2 = 0; l2 < cElements; l2++)
{
HRESULT hRes2;
ISWbemMethod *pMethod = NULL;
if (SUCCEEDED(hRes2 = m_pMethodSet->Next (0, &pMethod)))
{
if (NULL == pMethod)
{
break;
}
else
{
// Set the object into the variant array; note that pObject
// has been addref'd as a result of the Next() call above
pVar[l2].vt = VT_DISPATCH;
pVar[l2].pdispVal = pMethod;
m_pos++;
}
}
else
break;
}
if (NULL != pcElementFetched)
*pcElementFetched = l2;
}
}
}
return (l2 < cElements) ? S_FALSE : S_OK;
}
//***************************************************************************
//
// SCODE CMethodSetEnumVar::Clone
//
// DESCRIPTION:
//
// Create a copy of this enumeration
//
// PARAMETERS:
//
// ppEnum on successful return addresses the clone
//
// RETURN VALUES:
//
// S_OK success
// E_OUTOFMEMORY insufficient memory to complete operation
//
//***************************************************************************
HRESULT CMethodSetEnumVar::Clone (
IEnumVARIANT **ppEnum
)
{
HRESULT hr = E_FAIL;
if (NULL != ppEnum)
{
*ppEnum = NULL;
if (m_pMethodSet)
{
CMethodSetEnumVar *pEnum = new CMethodSetEnumVar (m_pMethodSet, m_pos);
if (!pEnum)
hr = WBEM_E_OUT_OF_MEMORY;
else if (FAILED(hr = pEnum->QueryInterface (IID_IEnumVARIANT, (PPVOID) ppEnum)))
delete pEnum;;
}
}
return hr;
}
//***************************************************************************
//
// SCODE CMethodSetEnumVar::Skip
//
// DESCRIPTION:
//
// Skips some elements in this enumeration
//
// PARAMETERS:
//
// ppEnum on successful return addresses the clone
//
// RETURN VALUES:
//
// S_OK success
// S_FALSE end of sequence reached prematurely
//
//***************************************************************************
HRESULT CMethodSetEnumVar::Skip(
ULONG cElements
)
{
HRESULT hr = S_FALSE;
long count = 0;
m_pMethodSet->get_Count (&count);
if (((ULONG) count) >= cElements + m_pos)
{
hr = S_OK;
m_pos += cElements;
}
else
m_pos = count;
return hr;
}
//***************************************************************************
//
// SCODE CMethodSetEnumVar::SeekCurrentPosition
//
// DESCRIPTION:
//
// Iterate to current position. Somewhat painful as there is no
// underlying iterator so we have to reset and then step. Note that we
// assume that the access to this iterator is apartment-threaded.
//
// PARAMETERS:
//
// ppEnum on successful return addresses the clone
//
// RETURN VALUES:
//
// S_OK success
// S_FALSE end of sequence reached prematurely
//
//***************************************************************************
bool CMethodSetEnumVar::SeekCurrentPosition ()
{
ISWbemMethod *pDummyObject = NULL;
m_pMethodSet->BeginEnumeration ();
// Traverse to the current position
ULONG i = 0;
for (; i < m_pos; i++)
{
if (WBEM_S_NO_ERROR != m_pMethodSet->Next (0, &pDummyObject))
break;
else
pDummyObject->Release ();
}
return (i == m_pos);
}