Re: [PATCH v5] fetch-pack: always allow fetching of literal SHA1s

[Jonathan Tan <jonathantanmy@google.com>]

On Fri, May 12, 2017 at 12:59 AM, Jeff King <peff@peff.net> wrote:
> On Fri, May 12, 2017 at 03:01:35PM +0900, Junio C Hamano wrote:
>> Also, tip_oids_contain() uses unmatched and newlist only on the
>> first call, but the internal API this patch establishes gives an
>> illusion (confusion) that updating unmatched and newlist while
>> making repeated to calls to this function may affect the outcome of
>> tip_oids_contain() function.  In fact, doesn't the loop that calls
>> this function extend "newlist" by extending the list at its tail?
>
> It does, but only with elements whose oids were already in the set. So I
> don't think it's wrong, but I agree the interface makes it a bit muddy.

To make the interface less muddy, would you agree with this (untested):

@@ -648,7 +669,9 @@ static void filter_refs(struct fetch_pack_args *args,
  continue;

  if ((allow_unadvertised_object_request &
-    (ALLOW_TIP_SHA1 | ALLOW_REACHABLE_SHA1))) {
+     (ALLOW_TIP_SHA1 | ALLOW_REACHABLE_SHA1)) ||
+      (check_tip_oids_initialized(&tip_oids, unmatched, newlist) &&
oidset_contains(&tip_oids,
+     &ref->old_oid))) {
  ref->match_status = REF_MATCHED;
  *newtail = copy_ref(ref);
  newtail = &(*newtail)->next;

(making the function-to-abstract be merely an initialization one,
instead of one that does 2 things). That decreases the scope of the
function that Jonathan Nieder and Peff wanted, but it might be a
warranted reduction in scope.