Some additional work let me enable a memory check for the clean shutdown case and
generally do a better job on other interfaces. Request queue waiters now awake
on shutdown and don't sleep once the queue is turned off. Much better semantically
for how this will be used.
With this commit, the cleanup paths should be production quality. Unit tests have been
expanded to include cases requiring thread termination and cleanup by the worker thread.
Special operation/request added to support the unit tests. Thread interface expanded
to include a very aggressive cancel() method that does not do cleanup but prevents the
thread from accessing objects that will be destroyed.
This is the first functional viewer pass with the HTTP work of the texture fetch
code performed by the llcorehttp library. Not exactly a 'drop-in' replacement
but a work-alike with some changes (e.g. handler notification in consumer
thread versus responder notification in worker thread).
This also includes some temporary changes in the priority scheme to prevent
the kind of priority inversion found in VWR-28996. Scheme used here does
provide liveness if not optimal responsiveness or order-of-operation.
The llcorehttp library at this point is far from optimally performing.
Its worker thread is making relatively poor use of cycles it gets and
it doesn't idle or sleep intelligently yet. This early integration step
helps shake out the interfaces, implementation niceties will be covered
soon.
Andrey Kleshchev