hash: provide per-algorithm null OIDs

Up until recently, object IDs did not have an algorithm member, only a
hash.  Consequently, it was possible to share one null (all-zeros)
object ID among all hash algorithms.  Now that we're going to be
handling objects from multiple hash algorithms, it's important to make
sure that all object IDs have a correct algorithm field.

Introduce a per-algorithm null OID, and add it to struct hash_algo.
Introduce a wrapper function as well, and use it everywhere we used to
use the null_oid constant.

Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This commit is contained in:
brian m. carlson
2021-04-26 01:02:56 +00:00
committed by Junio C Hamano
parent 5a6dce70d7
commit 14228447c9
42 changed files with 119 additions and 95 deletions

4
refs.c
View File

@ -1107,7 +1107,7 @@ int ref_transaction_create(struct ref_transaction *transaction,
if (!new_oid || is_null_oid(new_oid))
BUG("create called without valid new_oid");
return ref_transaction_update(transaction, refname, new_oid,
&null_oid, flags, msg, err);
null_oid(), flags, msg, err);
}
int ref_transaction_delete(struct ref_transaction *transaction,
@ -1119,7 +1119,7 @@ int ref_transaction_delete(struct ref_transaction *transaction,
if (old_oid && is_null_oid(old_oid))
BUG("delete called with old_oid set to zeros");
return ref_transaction_update(transaction, refname,
&null_oid, old_oid,
null_oid(), old_oid,
flags, msg, err);
}