// This helper function is a deadlock-safe method of waiting on a semaphore in a pxThread. If the
// thread is terminated or canceled by another thread or a nested action prior to the semaphore being
// posted, this function will detect that and throw a CancelEvent exception is thrown.
//
// Note: Use of this function only applies to semaphores which are posted by the worker thread. Calling
// this function from the context of the thread itself is an error, and a dev assertion will be generated.
//
// Exceptions:
// This function will rethrow exceptions raised by the persistent thread, if it throws an error
// while the calling thread is blocking (which also means the persistent thread has terminated).
//
void Threading::pxThread::WaitOnSelf( Semaphore& sem ) const
{
if( !AffinityAssert_DisallowFromSelf(pxDiagSpot) ) return;
while( true )
{
if( sem.WaitWithoutYield( wxTimeSpan(0, 0, 0, 333) ) ) return;
_selfRunningTest( L"semaphore" );
}
}
bool Threading::pxThread::WaitOnSelf( Semaphore& sem, const wxTimeSpan& timeout ) const
{
if( !AffinityAssert_DisallowFromSelf(pxDiagSpot) ) return true;
wxTimeSpan runningout( timeout );
while( runningout.GetMilliseconds() > 0 )
{
const wxTimeSpan interval( (SelfWaitInterval < runningout) ? SelfWaitInterval : runningout );
if( sem.WaitWithoutYield( interval ) ) return true;
_selfRunningTest( L"semaphore" );
runningout -= interval;
}
return false;
}
