@matheusbsbs / matheus-bagliano / commits / aba381c090

refs: create and use `ref_update_expects_existing_old_ref()`

The files and reftable backend, need to check if a ref must exist, so that the required validation can be done. A ref must exist only when the `old_oid` value of the update has been explicitly set and it is not the `null_oid` value. Since we also support symrefs now, we need to ensure that even when `old_target` is set a ref must exist. While this was missed when we added symref support in transactions, there are no active users of this path. As we introduce the 'symref-verify' command in the upcoming commits, it is important to fix this. So let's export this to a function called `ref_update_expects_existing_old_ref()` and expose it internally via 'refs-internal.h'. Helped-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Karthik Nayak <karthik.188@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>

Karthik Nayak committed Jun 7, 2024 at 15:32 UTC aba381c09034c2c31f3476e8cc9a46ea6889f1d5
4 files changed +14 -3
refs.c
+6
@@ -2863,3 +2863,9 @@ int ref_update_check_old_target(const char *referent, struct ref_update *update,
2863 referent, update->old_target);
2864 return -1;
2865 }
2866 +
2867 +int ref_update_expects_existing_old_ref(struct ref_update *update)
2868 +{
2869 + return (update->flags & REF_HAVE_OLD) &&
2870 + (!is_null_oid(&update->old_oid) || update->old_target);
2871 +}
refs/files-backend.c
+1 -2
@@ -2411,8 +2411,7 @@ static int lock_ref_for_update(struct files_ref_store *refs,
2411 struct strbuf *err)
2412 {
2413 struct strbuf referent = STRBUF_INIT;
2414 - int mustexist = (update->flags & REF_HAVE_OLD) &&
2415 - !is_null_oid(&update->old_oid);
2414 + int mustexist = ref_update_expects_existing_old_ref(update);
2415 int ret = 0;
2416 struct ref_lock *lock;
2417
refs/refs-internal.h
+6
@@ -765,4 +765,10 @@ int ref_update_has_null_new_value(struct ref_update *update);
765 int ref_update_check_old_target(const char *referent, struct ref_update *update,
766 struct strbuf *err);
767
768 +/*
769 + * Check if the ref must exist, this means that the old_oid or
770 + * old_target is non NULL.
771 + */
772 +int ref_update_expects_existing_old_ref(struct ref_update *update);
773 +
774 #endif /* REFS_REFS_INTERNAL_H */
refs/reftable-backend.c
+1 -1
@@ -827,7 +827,7 @@ static int reftable_be_transaction_prepare(struct ref_store *ref_store,
827 &current_oid, &referent, &u->type);
828 if (ret < 0)
829 goto done;
830 - if (ret > 0 && (!(u->flags & REF_HAVE_OLD) || is_null_oid(&u->old_oid))) {
830 + if (ret > 0 && !ref_update_expects_existing_old_ref(u)) {
831 /*
832 * The reference does not exist, and we either have no
833 * old object ID or expect the reference to not exist.