Re: [PATCH v3 7/8] fetch-pack: put shallow info in output parameter

On 06/25, Jonathan Tan wrote:

quoted

 static void update_shallow(struct fetch_pack_args *args,
-			   struct ref **sought, int nr_sought,
+			   struct ref *refs,

update_shallow() now takes in a linked list of refs instead of an array.
I see that the translation of this function is straightforward -
occasionally, we need to iterate through the linked list and count up
from 0 at the same time, but that is not a problem.

quoted

 			   struct shallow_info *si)
 {
 	struct oid_array ref = OID_ARRAY_INIT;
 	int *status;
-	int i;
+	int i = 0;

Remove the " = 0" - I've verified that it does not need to be there, and
it might inhibit useful "unintialized variable" warnings if others were
to change the code later.

Optional: I would also remove this declaration and declare "int i;" in
each of the blocks that need it.

quoted

 static int fetch_refs_via_pack(struct transport *transport,
-			       int nr_heads, struct ref **to_fetch)
+			       int nr_heads, struct ref **to_fetch,
+			       struct ref **fetched_refs)
 {
 	int ret = 0;
 	struct git_transport_data *data = transport->data;

@@ -354,8 +356,12 @@ static int fetch_refs_via_pack(struct transport *transport,
 	if (report_unmatched_refs(to_fetch, nr_heads))
 		ret = -1;
 
+	if (fetched_refs)
+		*fetched_refs = refs;
+	else
+		free_refs(refs);
+
 	free_refs(refs_tmp);
-	free_refs(refs);
 	free(dest);
 	return ret;
 }

Instead of just freeing the linked list, we return it if requested by
the client. This makes sense.

quoted

-int transport_fetch_refs(struct transport *transport, struct ref *refs)
+int transport_fetch_refs(struct transport *transport, struct ref *refs,
+			 struct ref **fetched_refs)
 {
 	int rc;
 	int nr_heads = 0, nr_alloc = 0, nr_refs = 0;
 	struct ref **heads = NULL;
+	struct ref *nop_head = NULL, **nop_tail = &nop_head;
 	struct ref *rm;
 
 	for (rm = refs; rm; rm = rm->next) {
 		nr_refs++;
 		if (rm->peer_ref &&
 		    !is_null_oid(&rm->old_oid) &&
-		    !oidcmp(&rm->peer_ref->old_oid, &rm->old_oid))
+		    !oidcmp(&rm->peer_ref->old_oid, &rm->old_oid)) {
+			/*
+			 * These need to be reported as fetched, but we don't
+			 * actually need to fetch them.
+			 */
+			if (fetched_refs) {
+				struct ref *nop_ref = copy_ref(rm);
+				*nop_tail = nop_ref;
+				nop_tail = &nop_ref->next;
+			}
 			continue;
+		}
 		ALLOC_GROW(heads, nr_heads + 1, nr_alloc);
 		heads[nr_heads++] = rm;
 	}

@@ -1245,7 +1263,11 @@ int transport_fetch_refs(struct transport *transport, struct ref *refs)
 			heads[nr_heads++] = rm;
 	}
 
-	rc = transport->vtable->fetch(transport, nr_heads, heads);
+	rc = transport->vtable->fetch(transport, nr_heads, heads, fetched_refs);
+	if (fetched_refs && nop_head) {
+		*nop_tail = *fetched_refs;
+		*fetched_refs = nop_head;
+	}
 
 	free(heads);
 	return rc;

And sometimes, even if we are merely simulating the fetching of refs, we
still need to report those refs in fetched_refs. This is correct.

I also see that t5703 now passes.

Besides enabling the writing of subsequent patches, I see that this also
makes the API clearer in that the input refs to transport_fetch_refs()
are not overloaded to output shallow information. Other than the " = 0"
change above, this patch looks good to me.

Perfect, I'll just drop the " = 0" part (making the diff slightly
smaller)

-- 
Brandon Williams