void MFStream::doRead()
{
bool readDone = true;
IUnknown *pUnk = NULL;
HRESULT hr = m_currentReadResult->GetObject(&pUnk);
if (SUCCEEDED(hr)) {
//do actual read
AsyncReadState *state = static_cast<AsyncReadState*>(pUnk);
ULONG cbRead;
Read(state->pb(), state->cb() - state->bytesRead(), &cbRead);
pUnk->Release();
state->setBytesRead(cbRead + state->bytesRead());
if (state->cb() > state->bytesRead() && !m_stream->atEnd()) {
readDone = false;
}
}
if (readDone) {
//now inform the original caller
m_currentReadResult->SetStatus(hr);
MFInvokeCallback(m_currentReadResult);
}
}
STDMETHODIMP MFStream::EndRead(IMFAsyncResult* pResult, ULONG *pcbRead)
{
if (!pcbRead)
return E_INVALIDARG;
IUnknown *pUnk;
pResult->GetObject(&pUnk);
AsyncReadState *state = static_cast<AsyncReadState*>(pUnk);
*pcbRead = state->bytesRead();
pUnk->Release();
m_currentReadResult->Release();
m_currentReadResult = NULL;
return S_OK;
}