HRESULT
CAsyncIo::SyncRead(
LONGLONG llPos,
LONG lLength,
BYTE* pBuffer)
{
if (IsAligned(llPos) &&
IsAligned(lLength) &&
IsAligned((LONG) pBuffer)) {
LONG cbUnused;
return SyncReadAligned(llPos, lLength, pBuffer, &cbUnused, NULL);
}
CAsyncRequest request;
HRESULT hr = request.Request(
this,
m_pStream,
llPos,
lLength,
FALSE,
pBuffer,
NULL,
0);
if (FAILED(hr)) {
return hr;
}
return request.Complete();
}
// perform a synchronous read request on this thread.
// may not be aligned - so we will have to buffer.
HRESULT
CAsyncIo::SyncRead(
LONGLONG llPos,
LONG lLength,
BYTE * pBuffer)
{
if(IsAligned(llPos) &&
IsAligned(lLength) &&
IsAligned((LONG_PTR) pBuffer))
{
LONG cbUnused;
return SyncReadAligned(llPos, lLength, pBuffer, &cbUnused, NULL);
}
// not aligned with requirements - use buffered file handle.
//!!! might want to fix this to buffer the data ourselves?
CAsyncRequest request;
HRESULT hr = request.Request(this,
m_pStream,
llPos,
lLength,
FALSE,
pBuffer,
NULL,
0);
if(FAILED(hr))
{
return hr;
}
return request.Complete();
}
STDMETHODIMP QAsyncReader::WaitForNext(DWORD timeout, IMediaSample **sample, DWORD_PTR *user)
{
QMutexLocker locker(&m_mutexWait);
if (!sample ||!user) {
return E_POINTER;
}
*sample = 0;
*user = 0;
AsyncRequest r = getNextRequest();
if (r.sample == 0) {
//there is no request in the queue
if (isFlushing()) {
return VFW_E_WRONG_STATE;
} else {
//First we need to lock the mutex
if (m_requestWait.wait(&m_mutexWait, timeout) == false) {
return VFW_E_TIMEOUT;
}
if (isFlushing()) {
return VFW_E_WRONG_STATE;
}
r = getNextRequest();
}
}
//at this point we're sure to have a request to proceed
if (r.sample == 0) {
return E_FAIL;
}
*sample = r.sample;
*user = r.user;
return SyncReadAligned(r.sample);
}
