datacache.c

这是一个开放源代码的与WINNT/WIN2K/WIN2003兼容的操作系统

 *   If a fallback is desired, just opening the first presentation stream
 *   is a possibility.
 */
static HRESULT DataCacheEntry_OpenPresStream(
  DataCacheEntry *This,
  IStream  **ppStm)
{
    STATSTG elem;
    IEnumSTATSTG *pEnum;
    HRESULT hr;

    if (!ppStm) return E_POINTER;

    hr = IStorage_EnumElements(This->storage, 0, NULL, 0, &pEnum);
    if (FAILED(hr)) return hr;

    while ((hr = IEnumSTATSTG_Next(pEnum, 1, &elem, NULL)) == S_OK)
    {
	if (DataCache_IsPresentationStream(&elem))
	{
	    IStream *pStm;

	    hr = IStorage_OpenStream(This->storage, elem.pwcsName,
				     NULL, STGM_READ | STGM_SHARE_EXCLUSIVE, 0,
				     &pStm);
	    if (SUCCEEDED(hr))
	    {
		PresentationDataHeader header;
		ULONG actual_read;
                CLIPFORMAT clipformat;

                hr = read_clipformat(pStm, &clipformat);

                if (hr == S_OK)
                    hr = IStream_Read(pStm, &header, sizeof(header), &actual_read);

		/* can't use SUCCEEDED(hr): S_FALSE counts as an error */
		if (hr == S_OK && actual_read == sizeof(header)
		    && header.dvAspect == This->fmtetc.dwAspect)
		{
		    /* Rewind the stream before returning it. */
		    LARGE_INTEGER offset;
		    offset.u.LowPart = 0;
		    offset.u.HighPart = 0;
		    IStream_Seek(pStm, offset, STREAM_SEEK_SET, NULL);

		    *ppStm = pStm;

		    CoTaskMemFree(elem.pwcsName);
		    IEnumSTATSTG_Release(pEnum);

		    return S_OK;
		}

		IStream_Release(pStm);
	    }
	}

	CoTaskMemFree(elem.pwcsName);
    }

    IEnumSTATSTG_Release(pEnum);

    return (hr == S_FALSE ? OLE_E_BLANK : hr);
}

/************************************************************************
 * DataCacheEntry_LoadData
 *
 * This method will read information for the requested presentation
 * into the given structure.
 *
 * Param:
 *   This - The entry to load the data from.
 *
 * Returns:
 *   This method returns a metafile handle if it is successful.
 *   it will return 0 if not.
 */
static HRESULT DataCacheEntry_LoadData(DataCacheEntry *This)
{
  IStream*      presStream = NULL;
  HRESULT       hres;
  ULARGE_INTEGER current_pos;
  STATSTG       streamInfo;
  void*         metafileBits;
  METAFILEPICT *mfpict;
  HGLOBAL       hmfpict;
  PresentationDataHeader header;
  CLIPFORMAT    clipformat;
  static const LARGE_INTEGER offset_zero;

  /*
   * Open the presentation stream.
   */
  hres = DataCacheEntry_OpenPresStream(
           This,
	   &presStream);

  if (FAILED(hres))
    return hres;

  /*
   * Get the size of the stream.
   */
  hres = IStream_Stat(presStream,
		      &streamInfo,
		      STATFLAG_NONAME);

  /*
   * Read the header.
   */

  hres = read_clipformat(presStream, &clipformat);
  if (FAILED(hres))
  {
      IStream_Release(presStream);
      return hres;
  }

  hres = IStream_Read(
                      presStream,
                      &header,
                      sizeof(PresentationDataHeader),
                      NULL);
  if (hres != S_OK)
  {
      IStream_Release(presStream);
      return E_FAIL;
  }

  hres = IStream_Seek(presStream, offset_zero, STREAM_SEEK_CUR, &current_pos);

  streamInfo.cbSize.QuadPart -= current_pos.QuadPart;

  hmfpict = GlobalAlloc(GMEM_MOVEABLE, sizeof(METAFILEPICT));
  if (!hmfpict)
  {
      IStream_Release(presStream);
      return E_OUTOFMEMORY;
  }
  mfpict = GlobalLock(hmfpict);

  /*
   * Allocate a buffer for the metafile bits.
   */
  metafileBits = HeapAlloc(GetProcessHeap(),
			   0,
			   streamInfo.cbSize.u.LowPart);

  /*
   * Read the metafile bits.
   */
  hres = IStream_Read(
	   presStream,
	   metafileBits,
	   streamInfo.cbSize.u.LowPart,
	   NULL);

  /*
   * Create a metafile with those bits.
   */
  if (SUCCEEDED(hres))
  {
    /* FIXME: get this from the stream */
    mfpict->mm = MM_ANISOTROPIC;
    mfpict->xExt = header.dwObjectExtentX;
    mfpict->yExt = header.dwObjectExtentY;
    mfpict->hMF = SetMetaFileBitsEx(streamInfo.cbSize.u.LowPart, metafileBits);
    if (!mfpict->hMF)
      hres = E_FAIL;
  }

  GlobalUnlock(hmfpict);
  if (SUCCEEDED(hres))
  {
    This->data_cf = This->fmtetc.cfFormat;
    This->stgmedium.tymed = TYMED_MFPICT;
    This->stgmedium.u.hMetaFilePict = hmfpict;
  }
  else
    GlobalFree(hmfpict);

  /*
   * Cleanup.
   */
  HeapFree(GetProcessHeap(), 0, metafileBits);
  IStream_Release(presStream);

  return hres;
}

static HRESULT DataCacheEntry_CreateStream(DataCacheEntry *This,
                                           IStorage *storage, IStream **stream)
{
    HRESULT hr;
    WCHAR wszName[] = {2,'O','l','e','P','r','e','s',
        '0' + (This->stream_number / 100) % 10,
        '0' + (This->stream_number / 10) % 10,
        '0' + This->stream_number % 10, 0};

    /* FIXME: cache the created stream in This? */
    hr = IStorage_CreateStream(storage, wszName,
                               STGM_READWRITE | STGM_SHARE_EXCLUSIVE | STGM_CREATE,
                               0, 0, stream);
    return hr;
}

static HRESULT DataCacheEntry_Save(DataCacheEntry *This, IStorage *storage,
                                   BOOL same_as_load)
{
    PresentationDataHeader header;
    HRESULT hr;
    IStream *pres_stream;
    void *data = NULL;

    TRACE("stream_number = %d, fmtetc = %s\n", This->stream_number, debugstr_formatetc(&This->fmtetc));

    hr = DataCacheEntry_CreateStream(This, storage, &pres_stream);
    if (FAILED(hr))
        return hr;

    hr = write_clipformat(pres_stream, This->data_cf);
    if (FAILED(hr))
        return hr;

    if (This->fmtetc.ptd)
        FIXME("ptd not serialized\n");
    header.unknown3 = 4;
    header.dvAspect = This->fmtetc.dwAspect;
    header.lindex = This->fmtetc.lindex;
    header.tymed = This->stgmedium.tymed;
    header.unknown7 = 0;
    header.dwObjectExtentX = 0;
    header.dwObjectExtentY = 0;
    header.dwSize = 0;

    /* size the data */
    switch (This->data_cf)
    {
        case CF_METAFILEPICT:
        {
            if (This->stgmedium.tymed != TYMED_NULL)
            {
                const METAFILEPICT *mfpict = GlobalLock(This->stgmedium.u.hMetaFilePict);
                if (!mfpict)
                {
                    IStream_Release(pres_stream);
                    return DV_E_STGMEDIUM;
                }
                header.dwObjectExtentX = mfpict->xExt;
                header.dwObjectExtentY = mfpict->yExt;
                header.dwSize = GetMetaFileBitsEx(mfpict->hMF, 0, NULL);
                GlobalUnlock(This->stgmedium.u.hMetaFilePict);
            }
            break;
        }
        default:
            break;
    }

    /*
     * Write the header.
     */
    hr = IStream_Write(pres_stream, &header, sizeof(PresentationDataHeader),
                       NULL);
    if (FAILED(hr))
    {
        IStream_Release(pres_stream);
        return hr;
    }

    /* get the data */
    switch (This->data_cf)
    {
        case CF_METAFILEPICT:
        {
            if (This->stgmedium.tymed != TYMED_NULL)
            {
                const METAFILEPICT *mfpict = GlobalLock(This->stgmedium.u.hMetaFilePict);
                if (!mfpict)
                {
                    IStream_Release(pres_stream);
                    return DV_E_STGMEDIUM;
                }
                data = HeapAlloc(GetProcessHeap(), 0, header.dwSize);
                GetMetaFileBitsEx(mfpict->hMF, header.dwSize, data);
                GlobalUnlock(This->stgmedium.u.hMetaFilePict);
            }
            break;
        }
        default:
            break;
    }

    if (data)
        hr = IStream_Write(pres_stream, data, header.dwSize, NULL);

    IStream_Release(pres_stream);
    return hr;
}

/* helper for copying STGMEDIUM of type bitmap, MF, EMF or HGLOBAL.
* does no checking of whether src_stgm has a supported tymed, so this should be
* done in the caller */
static HRESULT copy_stg_medium(CLIPFORMAT cf, STGMEDIUM *dest_stgm,
                               const STGMEDIUM *src_stgm)
{
    if (src_stgm->tymed == TYMED_MFPICT)
    {
        const METAFILEPICT *src_mfpict = GlobalLock(src_stgm->u.hMetaFilePict);
        METAFILEPICT *dest_mfpict;

        if (!src_mfpict)
            return DV_E_STGMEDIUM;
        dest_stgm->u.hMetaFilePict = GlobalAlloc(GMEM_MOVEABLE, sizeof(METAFILEPICT));
        dest_mfpict = GlobalLock(dest_stgm->u.hMetaFilePict);
        if (!dest_mfpict)
        {
            GlobalUnlock(src_stgm->u.hMetaFilePict);
            return E_OUTOFMEMORY;
        }
        *dest_mfpict = *src_mfpict;
        dest_mfpict->hMF = CopyMetaFileW(src_mfpict->hMF, NULL);
        GlobalUnlock(src_stgm->u.hMetaFilePict);
        GlobalUnlock(dest_stgm->u.hMetaFilePict);
    }
    else if (src_stgm->tymed != TYMED_NULL)
    {
        dest_stgm->u.hGlobal = OleDuplicateData(src_stgm->u.hGlobal, cf,
                                                GMEM_MOVEABLE);
        if (!dest_stgm->u.hGlobal)
            return E_OUTOFMEMORY;
    }
    dest_stgm->tymed = src_stgm->tymed;
    dest_stgm->pUnkForRelease = src_stgm->pUnkForRelease;
    if (dest_stgm->pUnkForRelease)
        IUnknown_AddRef(dest_stgm->pUnkForRelease);
    return S_OK;
}

static HRESULT DataCacheEntry_SetData(DataCacheEntry *This,
                                      const FORMATETC *formatetc,
                                      const STGMEDIUM *stgmedium,
                                      BOOL fRelease)
{
    if ((!This->fmtetc.cfFormat && !formatetc->cfFormat) ||
        (This->fmtetc.tymed == TYMED_NULL && formatetc->tymed == TYMED_NULL) ||
        stgmedium->tymed == TYMED_NULL)
    {
        WARN("invalid formatetc\n");
        return DV_E_FORMATETC;
    }

    This->dirty = TRUE;
    ReleaseStgMedium(&This->stgmedium);
    This->data_cf = This->fmtetc.cfFormat ? This->fmtetc.cfFormat : formatetc->cfFormat;
    if (fRelease)
    {
        This->stgmedium = *stgmedium;
        return S_OK;
    }
    else
        return copy_stg_medium(This->data_cf,
                               &This->stgmedium, stgmedium);
}

static HRESULT DataCacheEntry_GetData(DataCacheEntry *This,
                                      STGMEDIUM *stgmedium)
{
    if (stgmedium->tymed == TYMED_NULL && This->storage)
    {
        HRESULT hr = DataCacheEntry_LoadData(This);
        if (FAILED(hr))
            return hr;
    }
    if (stgmedium->tymed == TYMED_NULL)
        return OLE_E_BLANK;
    return copy_stg_medium(This->data_cf, stgmedium, &This->stgmedium);
}

static inline HRESULT DataCacheEntry_DiscardData(DataCacheEntry *This)
{
    ReleaseStgMedium(&This->stgmedium);
    This->data_cf = This->fmtetc.cfFormat;
    return S_OK;
}

static inline void DataCacheEntry_HandsOffStorage(DataCacheEntry *This)
{
    if (This->storage)
    {
        IStorage_Release(This->storage);
        This->storage = NULL;
    }
}

/*********************************************************
 * Method implementation for the  non delegating IUnknown
 * part of the DataCache class.
 */

/************************************************************************
 * DataCache_NDIUnknown_QueryInterface (IUnknown)
 *
 * See Windows documentation for more details on IUnknown methods.
 *
 * This version of QueryInterface will not delegate it's implementation
 * to the outer unknown.
 */
static HRESULT WINAPI DataCache_NDIUnknown_QueryInterface(
            IUnknown*      iface,
            REFIID         riid,
            void**         ppvObject)
{
  DataCache *this = impl_from_NDIUnknown(iface);

  /*
   * Perform a sanity check on the parameters.
   */
  if ( (this==0) || (ppvObject==0) )
    return E_INVALIDARG;

  /*
   * Initialize the return parameter.
   */
  *ppvObject = 0;

  /*
   * Compare the riid with the interface IDs implemented by this object.
   */
  if (memcmp(&IID_IUnknown, riid, sizeof(IID_IUnknown)) == 0)
  {
    *ppvObject = iface;
  }
  else if (memcmp(&IID_IDataObject, riid, sizeof(IID_IDataObject)) == 0)
  {
    *ppvObject = (IDataObject*)&(this->lpVtbl);
  }
  else if ( (memcmp(&IID_IPersistStorage, riid, sizeof(IID_IPersistStorage)) == 0)  ||
	    (memcmp(&IID_IPersist, riid, sizeof(IID_IPersist)) == 0) )
  {
    *ppvObject = (IPersistStorage*)&(this->lpvtblIPersistStorage);
  }
  else if ( (memcmp(&IID_IViewObject, riid, sizeof(IID_IViewObject)) == 0) ||
	    (memcmp(&IID_IViewObject2, riid, sizeof(IID_IViewObject2)) == 0) )
  {
    *ppvObject = (IViewObject2*)&(this->lpvtblIViewObject);
  }
  else if ( (memcmp(&IID_IOleCache, riid, sizeof(IID_IOleCache)) == 0) ||
	    (memcmp(&IID_IOleCache2, riid, sizeof(IID_IOleCache2)) == 0) )
  {
    *ppvObject = (IOleCache2*)&(this->lpvtblIOleCache2);
  }
  else if (memcmp(&IID_IOleCacheControl, riid, sizeof(IID_IOleCacheControl)) == 0)