[Libguestfs] [PATCH libnbd 2/4] lib: Split nbd_aio_is_* functions into internal.

[Richard W.M. Jones]

On Wed, Jun 05, 2019 at 09:34:37AM -0500, Eric Blake wrote:
> While we've fixed our internal uses, external callers may still have a
> race when calling multiple nbd_aio_is_* functions in a row, since the
> state can change between those functions.  Is that a problem?  Are there
> any common state combinations (such as is_ready||is_processing) that
> warrant their own API entry points so as to be race-free?

Possibly.  I guess if we discover such places we could add an atomic
function like:

  nbd_aio_is_state (nbd, READY|PROCESSING);

Rich.

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