STDMETHODIMP CBaseReferenceClock::GetTime(REFERENCE_TIME *pTime)
{
HRESULT hr;
if (pTime)
{
REFERENCE_TIME rtNow;
Lock();
rtNow = GetPrivateTime();
if (rtNow > m_rtLastGotTime)
{
m_rtLastGotTime = rtNow;
hr = S_OK;
}
else
{
hr = S_FALSE;
}
*pTime = m_rtLastGotTime;
Unlock();
MSR_INTEGER(m_idGetSystemTime, LONG((*pTime) / (UNITS/MILLISECONDS)) );
}
else hr = E_POINTER;
return hr;
}
STDMETHODIMP CBaseReferenceClock::GetTime(__out REFERENCE_TIME *pTime)
{
HRESULT hr;
if (pTime)
{
REFERENCE_TIME rtNow;
Lock();
rtNow = GetPrivateTime();
if (rtNow > m_rtLastGotTime)
{
m_rtLastGotTime = rtNow;
hr = S_OK;
}
else
{
hr = S_FALSE;
}
*pTime = m_rtLastGotTime;
Unlock();
MSR_INTEGER(m_idGetSystemTime, LONG((*pTime) / (UNITS/MILLISECONDS)) );
#ifdef DXMPERF
PERFLOG_GETTIME( (IReferenceClock *) this, *pTime );
#endif // DXMPERF
}
else hr = E_POINTER;
return hr;
}
HRESULT CBaseReferenceClock::AdviseThread()
{
DWORD dwWait = INFINITE;
// The first thing we do is wait until something interesting happens
// (meaning a first advise or shutdown). This prevents us calling
// GetPrivateTime immediately which is goodness as that is a virtual
// routine and the derived class may not yet be constructed. (This
// thread is created in the base class constructor.)
while ( !m_bAbort )
{
// Wait for an interesting event to happen
DbgLog((LOG_TIMING, 3, TEXT("CBaseRefClock::AdviseThread() Delay: %lu ms"), dwWait ));
WaitForSingleObject(m_pSchedule->GetEvent(), dwWait);
if (m_bAbort) break;
// There are several reasons why we need to work from the internal
// time, mainly to do with what happens when time goes backwards.
// Mainly, it stop us looping madly if an event is just about to
// expire when the clock goes backward (i.e. GetTime stop for a
// while).
const REFERENCE_TIME rtNow = GetPrivateTime();
DbgLog((LOG_TIMING, 3,
TEXT("CBaseRefClock::AdviseThread() Woke at = %lu ms"),
ConvertToMilliseconds(rtNow) ));
// We must add in a millisecond, since this is the resolution of our
// WaitForSingleObject timer. Failure to do so will cause us to loop
// franticly for (approx) 1 a millisecond.
m_rtNextAdvise = m_pSchedule->Advise( 10000 + rtNow );
LONGLONG llWait = m_rtNextAdvise - rtNow;
ASSERT( llWait > 0 );
llWait = ConvertToMilliseconds(llWait);
// DON'T replace this with a max!! (The type's of these things is VERY important)
dwWait = (llWait > REFERENCE_TIME(UINT_MAX)) ? UINT_MAX : DWORD(llWait);
};
return NOERROR;
}
