SIMPDATA.CPP

//+----------------------------------------------------------------------- 
// 
//  Simple Tabular Data Object 
//  Copyright (C) Microsoft Corporation, 1996, 1997 
// 
//  File:       SimpData.cpp 
// 
//  Contents:   Implementation of the CSimpleTabularData COM object. 
// 
//------------------------------------------------------------------------ 
 
#include "stdafx.h" 
#include "STD.h" 
#include "TDC.h" 
#include <MLang.h> 
#include "Notify.h" 
#include "TDCParse.h" 
#include "TDCArr.h" 
#include "SimpData.h" 
#include "TDCIds.h" 
 
 
//------------------------------------------------------------------------ 
// 
//  Method:    CSimpleTabularData() - Constructor 
// 
//  Synopsis:  Clears internal data.  Due to the COM model, the 
//             member function "Create" should be called to actually 
//             initialize the STD data structures. 
//------------------------------------------------------------------------ 
 
CSimpleTabularData::CSimpleTabularData() : m_cRef(1), m_pTDCArr(NULL) 
{ 
} 
 
//------------------------------------------------------------------------ 
// 
//  Method:    Create() 
// 
//  Synopsis:  Initializes STD.   
//             This method should be called after an STD object is contructed 
//             to initialize it. 
// 
//  Arguments: pTDCArr      Pointer to the TDCArr object containing the 
//                          data for this control. 
// 
//  Returns:   Nothing. 
// 
//------------------------------------------------------------------------ 
 
void 
CSimpleTabularData::Create(CTDCArr *pTDCArr) 
{ 
    m_pTDCArr = pTDCArr; 
    if (m_pTDCArr != NULL) 
        m_pTDCArr->AddRef(); 
} 
 
 
//------------------------------------------------------------------------ 
// 
//  Method:    ~CSimpleTabularData() 
// 
//  Synopsis:  Destructor 
// 
//------------------------------------------------------------------------ 
 
CSimpleTabularData::~CSimpleTabularData() 
{ 
    if (m_pTDCArr != NULL) 
        m_pTDCArr->Release(); 
} 
 
 
//------------------------------------------------------------------------ 
// 
//  Method:    Invalidate() 
// 
//  Synopsis:  Marks the current interface as invalid.  References to 
//             the TDCArr object are released.  Subsequent calls to the 
//             SimpleTabularData interface will return the code E_INVALID. 
// 
//  Arguments: None. 
// 
//  Returns:   S_OK to indicate success. 
// 
//------------------------------------------------------------------------ 
 
STDMETHODIMP 
CSimpleTabularData::Invalidate() 
{ 
    if (m_pTDCArr != NULL) 
    { 
        m_pTDCArr->Release(); 
        m_pTDCArr = NULL; 
    } 
    return S_OK; 
} 
 
 
////////////////////////////////////////////////////////////////////////// 
// 
//        Implementation of IUnknown COM interface. 
//        ----------------------------------------- 
// 
////////////////////////////////////////////////////////////////////////// 
 
//+----------------------------------------------------------------------- 
// 
//  Method:    QueryInterface() 
// 
//  Synopsis:  Implements part of the standard IUnknown COM interface. 
//               (Returns a pointer to this COM object) 
// 
//  Arguments: riid          GUID to recognise 
//             ppv           Pointer to this COM object [OUT] 
// 
//  Returns:   S_OK upon success. 
//             E_NOINTERFACE if queried for an unrecognised interface. 
// 
//+----------------------------------------------------------------------- 
 
STDMETHODIMP 
CSimpleTabularData::QueryInterface (REFIID riid, LPVOID * ppv) 
{ 
    HRESULT hr; 
 
    _ASSERTE(ppv != NULL); 
 
    // This is the non-delegating IUnknown implementation 
    if (riid == IID_IUnknown || riid == IID_OLEDBSimpleProvider) 
    { 
        *ppv = this; 
        ((LPUNKNOWN)*ppv)->AddRef(); 
        hr = S_OK; 
    } 
    else 
    { 
        *ppv = NULL; 
        hr = E_NOINTERFACE; 
    } 
 
#ifdef _ATL_DEBUG_QI 
    AtlDumpIID(riid, _T("CSimpleTabularData"), hr); 
#endif 
    return hr; 
} 
 
 
//+----------------------------------------------------------------------- 
// 
//  Method:    AddRef() 
// 
//  Synopsis:  Implements part of the standard IUnknown COM interface. 
//               (Adds a reference to this COM object) 
// 
//  Arguments: None 
// 
//  Returns:   Number of references to this COM object. 
// 
//+----------------------------------------------------------------------- 
 
STDMETHODIMP_(ULONG) 
CSimpleTabularData::AddRef () 
{ 
    return ++m_cRef; 
} 
 
 
//+----------------------------------------------------------------------- 
// 
//  Method:    Release() 
// 
//  Synopsis:  Implements part of the standard IUnknown COM interface. 
//               (Removes a reference to this COM object) 
// 
//  Arguments: None 
// 
//  Returns:   Number of remaining references to this COM object. 
//             0 if the COM object is no longer referenced. 
// 
//+----------------------------------------------------------------------- 
 
STDMETHODIMP_(ULONG) 
CSimpleTabularData::Release () 
{ 
    ULONG  retval; 
 
    m_cRef -= 1; 
    retval = m_cRef; 
    if (!m_cRef) 
    { 
        m_cRef = 0xffff;    //MM: Use this 'flag' for debug? 
        delete this; 
    } 
    return retval; 
}