[PATCH 2/2 resent] ws2_32: Add tests for exclusive flag for IOCTL_AFD_POLL.

[Zebediah Figura (she/her)]

On 9/1/21 6:04 PM, Zebediah Figura (she/her) wrote:
> I think these tests could be more extensive. For example:
> 
> * What happens if you try to perform a non-exclusive wait while an
> exclusive wait is in progress? i.e. the inverse of the test added here.
> 
> * Can we verify that exclusive waits are specific to a given socket
> (i.e. you can simultaneously do an exclusive wait on two different sockets?)
> 
> * Can we test that exclusive waits apply if two unequal sets overlap?
> 
> * Can you do an exclusive wait on the same socket from two different
> threads?
> 
> There's also a part of me that would like to know what can possibly be
> the point of this API; it's hard to even think of what "reasonable"
> behaviour is otherwise. Do you happen to know?
> 
> My best guess is that it's meant to explicitly interrupt poll requests
> somehow (what, I/O cancellation wasn't good enough for them?), in which
> case it'd be good to explicitly confirm or refute that the "exclusive"
> poll really does act like a normal poll, and doesn't e.g. return
> immediately.
> 

One more thing I meant to say: test_poll() is already big enough as it 
is, and the placement of these tests before the "basic" tests is not 
great either. I'd recommend putting all of the exclusive tests in a 
separate function.