Re: [PATCH 0/2] introduce list_for_each_entry_del

From: JÃrn Engel
Date: Mon Jun 03 2013 - 17:25:10 EST


On Mon, 3 June 2013 15:36:47 -0400, JÃrn Engel wrote:
> On Mon, 3 June 2013 13:49:30 -0700, Christoph Hellwig wrote:
> >
> > I can't say I like the structure.
> >
> > A list_pop that removes and entry from the head or returns NULL if the
> > list is empty would lead to nice while loops that are obviously
> > readable instead.
>
> Something like this?
>
> #define list_pop(head) \
> ({ struct list_head *____pos; \
> list_empty(head) ? NULL : (____pos = (head)->next, \
> list_del(____pos), ____pos) \
> })
>
> #define list_pop_entry(head, type, member) \
> ({ struct list_head *____pos; \
> list_empty(head) ? NULL : (____pos = (head)->next, \
> list_del(____pos), list_entry(____pos, type, member) \
> })
>
> Would be fine with me as well.

Actually, when I compare the two invocations, I prefer the
list_for_each_entry_del() variant over list_pop_entry().

while ((ref = list_pop_entry(&prefs, struct __prelim_ref, list))) {
list_for_each_entry_del(ref, &prefs, list) {

Christoph?

JÃrn

--
"Translations are and will always be problematic. They inflict violence
upon two languages." (translation from German)
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