windows-nt/Source/XPSP1/NT/admin/activec/samples/sdksamples/cmenu/dataobj.cpp
2020-09-26 16:20:57 +08:00

209 lines
6.3 KiB
C++

//==============================================================;
//
// This source code is only intended as a supplement to existing Microsoft documentation.
//
//
//
//
// 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.
//
// Copyright (C) 1999 Microsoft Corporation. All Rights Reserved.
//
//
//
//==============================================================;
#include "DataObj.h"
#include "guids.h"
#include "DeleBase.h"
//
// This is the minimum set of clipboard formats we must implement.
// MMC uses these to get necessary information from our snapin about
// our nodes.
//
// we need to do this to get around MMC.IDL - it explicitly defines
// the clipboard formats as WCHAR types...
#define _T_CCF_DISPLAY_NAME _T("CCF_DISPLAY_NAME")
#define _T_CCF_NODETYPE _T("CCF_NODETYPE")
#define _T_CCF_SZNODETYPE _T("CCF_SZNODETYPE")
#define _T_CCF_SNAPIN_CLASSID _T("CCF_SNAPIN_CLASSID")
#define _T_CCF_INTERNAL_SNAPIN _T("{2479DB32-5276-11d2-94F5-00C04FB92EC2}")
// These are the clipboard formats that we must supply at a minimum.
// mmc.h actually defined these. We can make up our own to use for
// other reasons. We don't need any others at this time.
UINT CDataObject::s_cfDisplayName = RegisterClipboardFormat(_T_CCF_DISPLAY_NAME);
UINT CDataObject::s_cfNodeType = RegisterClipboardFormat(_T_CCF_NODETYPE);
UINT CDataObject::s_cfSZNodeType = RegisterClipboardFormat(_T_CCF_SZNODETYPE);
UINT CDataObject::s_cfSnapinClsid = RegisterClipboardFormat(_T_CCF_SNAPIN_CLASSID);
UINT CDataObject::s_cfInternal = RegisterClipboardFormat(_T_CCF_INTERNAL_SNAPIN);
CDataObject::CDataObject(MMC_COOKIE cookie, DATA_OBJECT_TYPES context)
: m_lCookie(cookie), m_context(context), m_cref(0)
{
}
CDataObject::~CDataObject()
{
}
///////////////////////
// IUnknown implementation
///////////////////////
STDMETHODIMP CDataObject::QueryInterface(REFIID riid, LPVOID *ppv)
{
if (!ppv)
return E_FAIL;
*ppv = NULL;
if (IsEqualIID(riid, IID_IUnknown))
*ppv = static_cast<IDataObject *>(this);
else if (IsEqualIID(riid, IID_IDataObject))
*ppv = static_cast<IDataObject *>(this);
if (*ppv)
{
reinterpret_cast<IUnknown *>(*ppv)->AddRef();
return S_OK;
}
return E_NOINTERFACE;
}
STDMETHODIMP_(ULONG) CDataObject::AddRef()
{
return InterlockedIncrement((LONG *)&m_cref);
}
STDMETHODIMP_(ULONG) CDataObject::Release()
{
if (InterlockedDecrement((LONG *)&m_cref) == 0)
{
delete this;
return 0;
}
return m_cref;
}
/////////////////////////////////////////////////////////////////////////////
// IDataObject implementation
//
HRESULT CDataObject::GetDataHere(
FORMATETC *pFormatEtc, // [in] Pointer to the FORMATETC structure
STGMEDIUM *pMedium // [out] Pointer to the STGMEDIUM structure
)
{
const CLIPFORMAT cf = pFormatEtc->cfFormat;
IStream *pStream = NULL;
CDelegationBase *base = GetBaseNodeObject();
HRESULT hr = CreateStreamOnHGlobal( pMedium->hGlobal, FALSE, &pStream );
if ( FAILED(hr) )
return hr; // Minimal error checking
hr = DV_E_FORMATETC; // Unknown format
if (cf == s_cfDisplayName) {
const _TCHAR *pszName = base->GetDisplayName();
MAKE_WIDEPTR_FROMTSTR(wszName, pszName);
// get length of original string and convert it accordingly
ULONG ulSizeofName = lstrlen(pszName);
ulSizeofName++; // Count null character
ulSizeofName *= sizeof(WCHAR);
hr = pStream->Write(wszName, ulSizeofName, NULL);
} else if (cf == s_cfNodeType) {
const GUID *pGUID = (const GUID *)&base->getNodeType();
hr = pStream->Write(pGUID, sizeof(GUID), NULL);
} else if (cf == s_cfSZNodeType) {
LPOLESTR szGuid;
hr = StringFromCLSID(base->getNodeType(), &szGuid);
if (SUCCEEDED(hr)) {
hr = pStream->Write(szGuid, wcslen(szGuid), NULL);
CoTaskMemFree(szGuid);
}
} else if (cf == s_cfSnapinClsid) {
const GUID *pGUID = NULL;
pGUID = &CLSID_CComponentData;
hr = pStream->Write(pGUID, sizeof(GUID), NULL);
} else if (cf == s_cfInternal) {
// we are being asked to get our this pointer from the IDataObject interface
// only our own snap-in objects will know how to do this.
CDataObject *pThis = this;
hr = pStream->Write( &pThis, sizeof(CDataObject*), NULL );
}
pStream->Release();
return hr;
}
/////////////////////////////////////////////////////////////////////////////
// Global helper functions to help work with dataobjects and
// clipboard formats
//---------------------------------------------------------------------------
// Returns the current object based on the s_cfInternal clipboard format
//
CDataObject* GetOurDataObject (
LPDATAOBJECT lpDataObject // [in] IComponent pointer
)
{
HRESULT hr = S_OK;
CDataObject *pSDO = NULL;
// check to see if the data object is a special data object.
if ( IS_SPECIAL_DATAOBJECT (lpDataObject) )
{
//Code for handling a special data object goes here.
//Note that the MMC SDK samples do not handle
//special data objects, so we exit if we get one.
return NULL;
}
STGMEDIUM stgmedium = { TYMED_HGLOBAL, NULL };
FORMATETC formatetc = { CDataObject::s_cfInternal, NULL, DVASPECT_CONTENT, -1, TYMED_HGLOBAL };
// Allocate memory for the stream
stgmedium.hGlobal = GlobalAlloc( GMEM_SHARE, sizeof(CDataObject *));
if (!stgmedium.hGlobal) {
hr = E_OUTOFMEMORY;
}
if SUCCEEDED(hr)
// Attempt to get data from the object
hr = lpDataObject->GetDataHere( &formatetc, &stgmedium );
// stgmedium now has the data we need
if (SUCCEEDED(hr)) {
pSDO = *(CDataObject **)(stgmedium.hGlobal);
}
// if we have memory free it
if (stgmedium.hGlobal)
GlobalFree(stgmedium.hGlobal);
return pSDO;
} // end GetOurDataObject()