Re: marshalling

From:

ajk <anders43@gmail.com>

Newsgroups:

microsoft.public.vc.atl

Date:

Mon, 28 Jan 2008 20:31:58 -0800 (PST)

Message-ID:

<94dee2e4-496a-4553-9e8d-3eba09645f6b@q39g2000hsf.googlegroups.com>

On Jan 29, 11:37 am, "Igor Tandetnik" <itandet...@mvps.org> wrote:

but why do i get an error then? When both processes run in apartment
thread it works, but when one is free threaded, I get error 0x800706F4
a null reference was passed to the stub (When passing IA1 to IA2)?

Show your code. Also show the IDL definition of the two interfaces.
--

//
// to position the structure cursor inside the aspect directory
//

bool CdpADO::bPositionCursor
(
  /* in */ CComPtr<IAfwStructureCursor> &pCursor,
  /* in */ const std::string &sPath
)
{
  bool bOK = true;
  HRESULT hr = S_OK;
  ENTER( LogFile() );
  try
  {
    LogFile().logInfo( __FUNCTION__ " - %s", sPath.c_str() );
    long lCount = 0;

////////////////////////////////////////////////////////////
The following line fails (exception) if CoInitializeEx(NULL,
COINIT_MULTITHREADED ) is used but works if APARTMENT_THREADED
////////////////////////////////////////////////////////////

    hr = pCursor->InitFromPathName( m_pObjManager,
CComBSTR(sPath.c_str()), NULL, &lCount );

    if (FAILED(hr))
    {

//-----------------------------
//// here we get, with hr=0x800706F4
//-----------------------------

      LogFile().logInfo( __FUNCTION__ "::InitPathName returned hr=%X,
'%s'", hr, sPath.c_str() );
      bOK = false;
    }
<snipped rest>
}

//-----------------------------
// throws an exception if path(s) not found
//

void CdpADO::tryPositionCursor( CComPtr<IAfwStructureCursor>
&pCursor )
{
  const string sRoot( "[Control Structure]IP800xA" );
  const string sPath( "[Control Structure]IP800xA/LAB" );

  // try finding lab folder, if that is not there we go for the root
folder
  bool bPositioned = bPositionCursor( pCursor, sPath );
  if ( !bPositioned ) // didn't find it, try root
  {
    bPositioned = bPositionCursor( pCursor, sRoot );
  }
  if ( !bPositioned )
  {
    throw internal_exceptions::path_invalid();
  }
}

bool CdpADO::retrieveOracleInformation(oracleinfo_t &oracleInfo)
{
  bool bOK = false;

  try
  {
    CDescOpcError Desc;
    HRESULT hr = E_FAIL;
    CComPtr<IAfwStructureCursor> pCursor; // cursor to maneuver up the
parent chain

    hr = pCursor.CoCreateInstance( L"ABB.AfwStructureCursor" );
    if ( FAILED(hr) )
    {
      LogFile().logErr( "Failed creating cursor
retrieveOracleInformation, hr=0x%X, %s",
        hr, Desc.getHrErrorText(hr) );
      throw internal_exceptions::no_cursor();
    }

    // try finding right spot in aspect directory
    tryPositionCursor( pCursor );

    // position cursor in machines folder, look for oracle aspect, if
not found, go up one level until found
    do // loop over all tree levels
    {
<snipped>
    }
    while ( !bOK && SUCCEEDED(hr) );

    pCursor.Release();
  }
  catch(const exception &ex)
  {
  }
  catch(...)
  {
  }
  return bOK;
}

//-----------------------------
code showing the connection to object manager
//-----------------------------

bool CdpADO::connectToObjectManager()
{
  bool bOK = false;
  HRESULT hr = E_FAIL;

  try
  {
   const AfwSystemContextId* pSysCtxId = NULL; // connect to default
system
   const AfwKeyId* pDataMode =NULL; // live data active
   const BOOL displayDlg(FALSE); // no dialog if connection cannot
be established
   const BOOL localThread(TRUE); // shallow version of object
manager - loads faster, less performance

   hr =
m_pObjManager.Create(pSysCtxId,pDataMode,displayDlg,localThread);
  }
  catch(...)
  {
  ...
  }
  return bOK;
}

//-----------------------------
m_pObjManager declared as

CComPtr<IAfwObjectManager> m_pObjManager;

These IDL-files a very large and protected by copyright so I can only
show small part - hopefully the right part.
...

#define AFW_INTERFACE_STATUS 1408E154-ABF5-43Af-A11E-8F8964C5BFC0
#define AFW_STATUS_COMMITTED "committed"

..
//----------------------------
/// IDL
//----------------------------
[
    object,
    uuid(E4FD44F8-C773-11D0-8094-93F1B82D8B1E),
    helpstring("IAfwObjectManager Interface"),
    custom(AFW_INTERFACE_STATUS,AFW_STATUS_COMMITTED),
    pointer_default(unique)
]
interface IAfwObjectManager : IUnknown
{
   snipped lots of methods
};

//----------------------------
the other, where the IAfwObjectManager ptr is passed to:
//----------------------------
[
    object,
    uuid(AA98459F-DE27-11D2-8F21-000000000000),
    helpstring("IAfwStructureCursor Interface"),
    custom(AFW_INTERFACE_STATUS,AFW_STATUS_COMMIT),
    pointer_default(unique)
]
interface IAfwStructureCursor : IUnknown
{
...
    HRESULT InitFromPathName(
        [in] IAfwObjectManager* pObjMgr,
        [in] const BSTR pathName,
        [in] const AfwStructureId* pStructId,
        [out, retval] long* pSNCount);
...
};

tia
Anders.