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Pointer to NETRESOURCE

Hi, this is a little complicated...
I'm passing a pointer to NETRESOURCE to my class to be used later, like so:

NETRESOURCE *nr; //valid at this point
HTREEITEM ht;
CDomains * e = new CDomains( FALSE, &ht, nr );

Then in the class constructor I'm making a copy of the pointer:

CDomains( BOOL bWMI, HTREEITEM *hProvider, NETRESOURCE * nr = NULL, LPVOID r = NULL )
{
      m_hProvider = new HTREEITEM;
      memcpy(m_hProvider, hProvider, sizeof(HTREEITEM));
      if ( nr ) {
            m_pnr = new NETRESOURCE;
            memcpy(m_pnr, nr, sizeof(NETRESOURCE));
      } else {
            m_pnr = NULL;
      }
}

Now comes the tricky part. This class inherits from another class that has Start() function. I call it next:
e->Start();

The Start() function of the class CDomains inherits from:
void CSuper::Start()
{
      HANDLE      hThread = NULL;
      InterlockedIncrement( &g->ThreadCount );

      DWORD      id;
      hThread = CreateThread( NULL, THREAD_STACK_SIZE, Enumerate, this, CREATE_SUSPENDED, &id );

      DWORD dwWaitResult = WaitForSingleObject( g->hSemaphore, INFINITE); //wait

      switch( dwWaitResult )
      {

      case WAIT_OBJECT_0:
            {
                  if ( hThread ) {
                        // thread created
                        SetThreadPriority( hThread, THREAD_PRIORITY_LOWEST );
                        ResumeThread( hThread );
                  }
            }
            break;

      case WAIT_TIMEOUT:
      case WAIT_ABANDONED:
            {
                  //report error
                  TRACE(_T("startThreadProcessLog SEMAPHORE Timed Out"));
            }
            break;
      }
      CloseHandle( hThread );

}

This goes well, the parameter passed to Enumerate function (this) contains the inheriting class CDomain
with all variables still valid.

The Enumerate function:
DWORD WINAPI CSuper::Enumerate( LPVOID This )
{
       CSuper * o = ( CSuper *)This;
      o->Enumerate();
      return 0;
}

This where the things go sour. All the variables in o->CDomains are still valid,
numeric values in o->CDomains->m_pnr are still valid, but all the string
members of that struct are now invalid pointers.

Please help, I'm willing to give more points if necessary.

ASKER CERTIFIED SOLUTION

jkr

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jd9288

ASKER

Brilliant! I suspected this might be the case, but since I'm so unsure of myself,
I thought I'm missing something.

Could you please tell me why it would still work sometimes
the way I had it?

jkr

>>Could you please tell me why it would still work sometimes
>>the way I had it?

Because the strings are 'there' for a while, at least during an enumeration. You never know when the system will free the momry it used to store the strings in.

BTW, you could extend the above to

class CNetResource : public NETRESOURCE {

public:

CNetResource () { /* ... */ }
CNetResource ( const NETRESOURCE& nr) { /* ... */ }
CNetResource& operator=(const NETRESOURCE& nr) { /* ... */ }
};

to 'automate' that copying process.

jd9288

ASKER

Thank you very much, I think I'm getting there.