On 11/12/2014 14:13, Kevin Wolf wrote:
>> > +#define QSIMPLEQ_SPLIT_AFTER(head1, head2, elm, field) do { \
>> > + if (((head1)->sqh_first = (head2)->sqh_first) == NULL) { \
>> > + (head1)->sqh_last = &(head1)->sqh_first; \
>> > + } else { \
>> > + (head1)->sqh_last = &(elm)->field.sqe_next; \
>> > + if (((head2)->sqh_first = (elm)->field.sqe_next) == NULL) { \
>> > + (head2)->sqh_last = &(head2)->sqh_first; \
>> > + } \
>> > + } \
>> > +} while (/*CONSTCOND*/0)
> Wouldn't it be easier to write a macro that doesn't split a queue in
> two, but simply removes everything up to a given element?
Yeah, though I figured that in the common case you'd have to free those
elements or otherwise process them. But I left this patch last because
I wasn't sure about the API. Feel free to ignore it, also given the
above comment about EAGAIN.
Paolo
> Anyway, if you really want to implement a split operation, I think you
> also need to break the actual chain, i.e. (head1)->sqh_last.sqe_next =
> NULL.
