IFilter of IStream

[emmalee]

Indicating in my annex office documents (MS Office 03, 07). If you're loaded IFilter using a specific file, all OK, the filter works as follows:

HRESULT hr_f = LoadIFilter(filename, 0, (void **)&pFilter);

However, initialization from the buffer:

HRESULT hr_ss = BindIFilterFromStream(spStream, 0, (void **)&pFilter);

returns E_FAILand pFilternaturally, it doesn't work. From IStream I've inherited, the methods have been implemented, the main thing that is needed to initialize the right flame, I suspect, is in the method:

HRESULT StreamFilter::Stat(STATSTG * pstatstg, DWORD grfStatFlag)
{
   //Microsoft Office Ifilter from Windows Registry
   const IID CLSID_IFilter = {
       0xf07f3920,
       0x7b8c,
       0x11cf,
       { 0x9b, 0xe8, 0x00, 0xaa, 0x00, 0x4b, 0x99, 0x86 }
   //{f07f3920-7b8c-11cf-9be8-00aa004b9986}

};

LARGE_INTEGER pSize;

int fl = GetFileSizeEx(_hFile, &pSize);

memset(pstatstg, 0, sizeof(STATSTG));

pstatstg->clsid = CLSID_IFilter;

pstatstg->type = STGTY_STREAM;

pstatstg->cbSize.QuadPart = pSize.QuadPart;
return S_OK;

}

Options for initializing the structure pstatstg I've tried different, it's useless. ♪
After calling this method, judging by the set of calls goes to the query.dll and comes from there. E_FAIL♪ I don't know what else might be necessary.

There's a similar question, https://stackoverflow.com/questions/7313828/using-ifilter-in-c-sharp-and-retrieving-file-from-database-rather-than-file-syst/19504946?s=1%7C0.1214#19504946 and the method described for *.pdf really works on the plus. But unfortunately, MSO doesn't fit.

[obi]

Anyway, after a long search, I'm inspired by a solution. https://stackoverflow.com/questions/7313828/using-ifilter-in-c-sharp-and-retrieving-file-from-database-rather-than-file-syst/19504946?s=1%7C0.1214#19504946 , drank his crutches that work as I need.

Let the system choose the right xandler to expand the processed file:

HRESULT hr = LoadIFilter(L".doc", 0, (void **)&pFilter);

Then we need to initiate. IStream*:

IPersistStream *stream;
HRESULT hr_qi = pFilter->QueryInterface(&stream);
std::ifstream ifs(filename, ios::binary);

std::string content((std::istreambuf_iterator<char>(ifs)),

(std::istreambuf_iterator<char>()));
IStream *comStream;

HGLOBAL hMem = ::GlobalAlloc(GMEM_MOVEABLE, content.size());

LPVOID pDoc = ::GlobalLock(hMem);

memcpy(pDoc, content.c_str(), content.size());

::GlobalUnlock(hMem);

HRESULT hr_mem = ::CreateStreamOnHGlobal(hMem, true, &comStream);

HRESULT hr_stream_load = stream->Load(comStream);

Then we work with the filter, as in MSDN or GitHub examples:

if (SUCCEEDED(hr))

{

DWORD flags = 0;

HRESULT hr = pFilter->Init(IFILTER_INIT_INDEXING_ONLY |

IFILTER_INIT_APPLY_INDEX_ATTRIBUTES |

IFILTER_INIT_APPLY_CRAWL_ATTRIBUTES |

IFILTER_INIT_FILTER_OWNED_VALUE_OK |

IFILTER_INIT_APPLY_OTHER_ATTRIBUTES,

0, 0, &flags);

if (FAILED(hr))

{

pFilter->Release();

throw exception("IFilter::Init() failed");

}

Start();
STAT_CHUNK stat;

while (SUCCEEDED(hr = pFilter->GetChunk(&stat)))

{

if ((stat.flags & CHUNK_TEXT) != 0)

ProcessTextChunk(pFilter, stat);
 if ((stat.flags & CHUNK_VALUE) != 0)
    ProcessValueChunk(pFilter, stat);

}
Finish();
pFilter->Release();

}

else

{

throw exception("LoadIFilter() failed");

}

It should be emphasized that, in this situation, there is no need to implement its version. IStream*, unless you write Windows Search.