clipboard.c

这是一个开放源代码的与WINNT/WIN2K/WIN2003兼容的操作系统

  return hr;
}


/***********************************************************************
 * OleGetClipboard [OLE32.@]
 * Returns a pointer to our internal IDataObject which represents the conceptual
 * state of the Windows clipboard. If the current clipboard already contains
 * an IDataObject, our internal IDataObject will delegate to this object.
 */
HRESULT WINAPI OleGetClipboard(IDataObject** ppDataObj)
{
  HRESULT hr = S_OK;
  TRACE("()\n");

  /*
   * Make sure we have a clipboard object
   */
  OLEClipbrd_Initialize();

  if (!theOleClipboard)
    return E_OUTOFMEMORY;

  /* Return a reference counted IDataObject */
  hr = IDataObject_QueryInterface( (IDataObject*)&(theOleClipboard->lpvtbl1),
                                   &IID_IDataObject,  (void**)ppDataObj);
  return hr;
}

/******************************************************************************
 *              OleFlushClipboard        [OLE32.@]
 *  Renders the data from the source IDataObject into the windows clipboard
 *
 *  TODO: OleFlushClipboard needs to additionally handle TYMED_IStorage media
 *  by copying the storage into global memory. Subsequently the default
 *  data object exposed through OleGetClipboard must convert this TYMED_HGLOBAL
 *  back to TYMED_IStorage.
 */
HRESULT WINAPI OleFlushClipboard(void)
{
  IEnumFORMATETC* penumFormatetc = NULL;
  FORMATETC rgelt;
  HRESULT hr = S_OK;
  BOOL bClipboardOpen = FALSE;
  IDataObject* pIDataObjectSrc = NULL;

  TRACE("()\n");

  /*
   * Make sure we have a clipboard object
   */
  OLEClipbrd_Initialize();

  /*
   * Already flushed or no source DataObject? Nothing to do.
   */
  if (!theOleClipboard->pIDataObjectSrc)
    return S_OK;

  /*
   * Addref and save the source data object we are holding on to temporarily,
   * since it will be released when we empty the clipboard.
   */
  pIDataObjectSrc = theOleClipboard->pIDataObjectSrc;
  IDataObject_AddRef(pIDataObjectSrc);

  /*
   * Open the Windows clipboard
   */
  if ( !(bClipboardOpen = OpenClipboard(theOleClipboard->hWndClipboard)) )
    HANDLE_ERROR( CLIPBRD_E_CANT_OPEN );

  /*
   * Empty the current clipboard
   */
  if ( !EmptyClipboard() )
    HANDLE_ERROR( CLIPBRD_E_CANT_EMPTY );

  /*
   * Render all HGLOBAL formats supported by the source into
   * the windows clipboard.
   */
  if ( FAILED( hr = IDataObject_EnumFormatEtc( pIDataObjectSrc,
                                               DATADIR_GET,
                                               &penumFormatetc) ))
  {
    HANDLE_ERROR( hr );
  }

  while ( S_OK == IEnumFORMATETC_Next(penumFormatetc, 1, &rgelt, NULL) )
  {
    if ( rgelt.tymed == TYMED_HGLOBAL )
    {
      CHAR szFmtName[80];
      TRACE("(cfFormat=%d:%s)\n", rgelt.cfFormat,
            GetClipboardFormatNameA(rgelt.cfFormat, szFmtName, sizeof(szFmtName)-1)
              ? szFmtName : "");

      /*
       * Render the clipboard data
       */
      if ( FAILED(OLEClipbrd_RenderFormat( pIDataObjectSrc, &rgelt )) )
        continue;
    }
  }

  IEnumFORMATETC_Release(penumFormatetc);

  /*
   * Release the source data object we are holding on to
   */
  IDataObject_Release(pIDataObjectSrc);

CLEANUP:

  /*
   * Close Windows clipboard (It remains associated with our window)
   */
  if ( bClipboardOpen && !CloseClipboard() )
    hr = CLIPBRD_E_CANT_CLOSE;

  return hr;
}


/***********************************************************************
 *           OleIsCurrentClipboard [OLE32.@]
 */
HRESULT WINAPI OleIsCurrentClipboard(IDataObject *pDataObject)
{
  TRACE("()\n");
  /*
   * Make sure we have a clipboard object
   */
  OLEClipbrd_Initialize();

  if (!theOleClipboard)
    return E_OUTOFMEMORY;

  return (pDataObject == theOleClipboard->pIDataObjectSrc) ? S_OK : S_FALSE;
}


/*---------------------------------------------------------------------*
 *           Internal implementation methods for the OLE clipboard
 *---------------------------------------------------------------------*/

/***********************************************************************
 * OLEClipbrd_Initialize()
 * Initializes the OLE clipboard.
 */
void OLEClipbrd_Initialize(void)
{
  /*
   * Create the clipboard if necessary
   */
  if ( !theOleClipboard )
  {
    TRACE("()\n");
    theOleClipboard = OLEClipbrd_Construct();
  }
}


/***********************************************************************
 * OLEClipbrd_UnInitialize()
 * Un-Initializes the OLE clipboard
 */
void OLEClipbrd_UnInitialize(void)
{
  TRACE("()\n");
  /*
   * Destroy the clipboard if no one holds a reference to us.
   * Note that the clipboard was created with a reference count of 1.
   */
  if ( theOleClipboard && (theOleClipboard->ref <= 1) )
  {
    OLEClipbrd_Destroy( theOleClipboard );
  }
  else
  {
    WARN( "() : OLEClipbrd_UnInitialize called while client holds an IDataObject reference!\n");
  }
}


/*********************************************************
 * Construct the OLEClipbrd class.
 */
static OLEClipbrd* OLEClipbrd_Construct(void)
{
  OLEClipbrd* newObject = NULL;
  HGLOBAL hNewObject = 0;

  /*
   * Allocate space for the object. We use GlobalAlloc since we need
   * an HGLOBAL to expose our DataObject as a registered clipboard type.
   */
  hNewObject = GlobalAlloc( GMEM_DDESHARE|GMEM_MOVEABLE|GMEM_ZEROINIT,
                           sizeof(OLEClipbrd));
  if (hNewObject==0)
    return NULL;

  /*
   * Lock the handle for the entire lifetime of the clipboard.
   */
  newObject = GlobalLock(hNewObject);

  /*
   * Initialize the virtual function table.
   */
  newObject->lpvtbl1 = &OLEClipbrd_IDataObject_VTable;

  /*
   * Start with one reference count. The caller of this function
   * must release the interface pointer when it is done.
   */
  newObject->ref = 1;

  newObject->hSelf = hNewObject;

  /*
   * The Ole clipboard is a singleton - save the global handle and pointer
   */
  theOleClipboard = newObject;
  hTheOleClipboard = hNewObject;

  return theOleClipboard;
}

static void OLEClipbrd_Destroy(OLEClipbrd* ptrToDestroy)
{
  TRACE("()\n");

  if ( !ptrToDestroy )
    return;

  /*
   * Destroy the Ole clipboard window
   */
  if ( ptrToDestroy->hWndClipboard )
    OLEClipbrd_DestroyWindow(ptrToDestroy->hWndClipboard);

  /*
   * Free the actual OLE Clipboard structure.
   */
  TRACE("() - Destroying clipboard data object.\n");
  GlobalUnlock(ptrToDestroy->hSelf);
  GlobalFree(ptrToDestroy->hSelf);

  /*
   * The Ole clipboard is a singleton (ptrToDestroy == theOleClipboard)
   */
  theOleClipboard = NULL;
  hTheOleClipboard = 0;
}


/***********************************************************************
 * OLEClipbrd_CreateWindow()
 * Create the clipboard window
 */
static HWND OLEClipbrd_CreateWindow(void)
{
  HWND hwnd = 0;
  WNDCLASSEXA wcex;

  /*
   * Register the clipboard window class if necessary
   */
    ZeroMemory( &wcex, sizeof(WNDCLASSEXA));

    wcex.cbSize         = sizeof(WNDCLASSEXA);
    /* Windows creates this class with a style mask of 0
     * We don't bother doing this since the FindClassByAtom code
     * would have to be changed to deal with this idiosyncrasy. */
    wcex.style          = CS_GLOBALCLASS;
    wcex.lpfnWndProc    = OLEClipbrd_WndProc;
    wcex.hInstance      = 0;
    wcex.lpszClassName  = OLEClipbrd_WNDCLASS;

    RegisterClassExA(&wcex);

  /*
   * Create a hidden window to receive OLE clipboard messages
   */

/*
 *  If we need to store state info we can store it here.
 *  For now we don't need this functionality.
 *   ClipboardWindowInfo clipboardInfo;
 *   ZeroMemory( &trackerInfo, sizeof(ClipboardWindowInfo));
 */

  hwnd = CreateWindowA(OLEClipbrd_WNDCLASS,
				    "ClipboardWindow",
				    WS_POPUP | WS_CLIPSIBLINGS | WS_OVERLAPPED,
				    CW_USEDEFAULT, CW_USEDEFAULT,
				    CW_USEDEFAULT, CW_USEDEFAULT,
				    0,
				    0,
				    0,
				    0 /*(LPVOID)&clipboardInfo */);

  return hwnd;
}

/***********************************************************************
 * OLEClipbrd_DestroyWindow(HWND)
 * Destroy the clipboard window and unregister its class
 */
static void OLEClipbrd_DestroyWindow(HWND hwnd)
{
  /*
   * Destroy clipboard window and unregister its WNDCLASS
   */
  DestroyWindow(hwnd);
  UnregisterClassA( OLEClipbrd_WNDCLASS, 0 );
}

/***********************************************************************
 * OLEClipbrd_WndProc(HWND, unsigned, WORD, LONG)
 * Processes messages sent to the OLE clipboard window.
 * Note that we will intercept messages in our WndProc only when data
 * has been placed in the clipboard via OleSetClipboard().
 * i.e. Only when OLE owns the windows clipboard.
 */
static LRESULT CALLBACK OLEClipbrd_WndProc
  (HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam)
{
  switch (message)
  {
    /*
     * WM_RENDERFORMAT
     * We receive this message to allow us to handle delayed rendering of
     * a specific clipboard format when an application requests data in
     * that format by calling GetClipboardData.
     * (Recall that in OleSetClipboard, we used SetClipboardData to
     * make all HGLOBAL formats supported by the source IDataObject
     * available using delayed rendering)
     * On receiving this message we must actually render the data in the
     * specified format and place it on the clipboard by calling the
     * SetClipboardData function.
     */
    case WM_RENDERFORMAT:
    {
      FORMATETC rgelt;

      ZeroMemory( &rgelt, sizeof(FORMATETC));

      /*
       * Initialize FORMATETC to a Windows clipboard friendly format
       */
      rgelt.cfFormat = (UINT) wParam;
      rgelt.dwAspect = DVASPECT_CONTENT;
      rgelt.lindex = -1;
      rgelt.tymed = TYMED_HGLOBAL;

      TRACE("(): WM_RENDERFORMAT(cfFormat=%d)\n", rgelt.cfFormat);

      /*
       * Render the clipboard data.
       * (We must have a source data object or we wouldn't be in this WndProc)
       */
      OLEClipbrd_RenderFormat( (IDataObject*)&(theOleClipboard->lpvtbl1), &rgelt );

      break;
    }

    /*
     * WM_RENDERALLFORMATS
     * Sent before the clipboard owner window is destroyed.
     * We should receive this message only when OleUninitialize is called
     * while we have an IDataObject in the clipboard.
     * For the content of the clipboard to remain available to other
     * applications, we must render data in all the formats the source IDataObject
     * is capable of generating, and place the data on the clipboard by calling
     * SetClipboardData.
     */
    case WM_RENDERALLFORMATS:
    {
      IEnumFORMATETC* penumFormatetc = NULL;
      FORMATETC rgelt;

      TRACE("(): WM_RENDERALLFORMATS\n");

      /*
       * Render all HGLOBAL formats supported by the source into
       * the windows clipboard.
       */
      if ( FAILED( IDataObject_EnumFormatEtc( (IDataObject*)&(theOleClipboard->lpvtbl1),
                                 DATADIR_GET, &penumFormatetc) ) )
      {
        WARN("(): WM_RENDERALLFORMATS failed to retrieve EnumFormatEtc!\n");
        return 0;
      }

      while ( S_OK == IEnumFORMATETC_Next(penumFormatetc, 1, &rgelt, NULL) )
      {
        if ( rgelt.tymed == TYMED_HGLOBAL )
        {
          /*
           * Render the clipboard data.
           */
          if ( FAILED(OLEClipbrd_RenderFormat( (IDataObject*)&(theOleClipboard->lpvtbl1), &rgelt )) )
            continue;

          TRACE("(): WM_RENDERALLFORMATS(cfFormat=%d)\n", rgelt.cfFormat);
        }
      }

      IEnumFORMATETC_Release(penumFormatetc);

      break;
    }

    /*
     * WM_DESTROYCLIPBOARD
     * This is sent by EmptyClipboard before the clipboard is emptied.
     * We should release any IDataObject we are holding onto when we receive
     * this message, since it indicates that the OLE clipboard should be empty
     * from this point on.
     */
    case WM_DESTROYCLIPBOARD:
    {
      TRACE("(): WM_DESTROYCLIPBOARD\n");
      /*
       * Release the data object we are holding on to
       */
      if ( theOleClipboard->pIDataObjectSrc )
      {
        IDataObject_Release(theOleClipboard->pIDataObjectSrc);
        theOleClipboard->pIDataObjectSrc = NULL;
      }
      break;
    }

/*
    case WM_ASKCBFORMATNAME:
    case WM_CHANGECBCHAIN:
    case WM_DRAWCLIPBOARD:
    case WM_SIZECLIPBOARD:
    case WM_HSCROLLCLIPBOARD:
    case WM_VSCROLLCLIPBOARD: