@@ -2417,6 +2417,22 @@ int initial_ref_transaction_commit(struct ref_transaction *transaction,
return refs->be->initial_transaction_commit(refs, transaction, err);
}
+void ref_transaction_for_each_queued_update(struct ref_transaction *transaction,
+ ref_transaction_for_each_queued_update_fn cb,
+ void *cb_data)
+{
+ int i;
+
+ for (i = 0; i < transaction->nr; i++) {
+ struct ref_update *update = transaction->updates[i];
+
+ cb(update->refname,
+ (update->flags & REF_HAVE_OLD) ? &update->old_oid : NULL,
+ (update->flags & REF_HAVE_NEW) ? &update->new_oid : NULL,
+ cb_data);
+ }
+}
+
int refs_delete_refs(struct ref_store *refs, const char *logmsg,
struct string_list *refnames, unsigned int flags)
{
@@ -776,6 +776,20 @@ int ref_transaction_abort(struct ref_transaction *transaction,
int initial_ref_transaction_commit(struct ref_transaction *transaction,
struct strbuf *err);
+/*
+ * Execute the given callback function for each of the reference updates which
+ * have been queued in the given transaction. `old_oid` and `new_oid` may be
+ * `NULL` pointers depending on whether the update has these object IDs set or
+ * not.
+ */
+typedef void ref_transaction_for_each_queued_update_fn(const char *refname,
+ const struct object_id *old_oid,
+ const struct object_id *new_oid,
+ void *cb_data);
+void ref_transaction_for_each_queued_update(struct ref_transaction *transaction,
+ ref_transaction_for_each_queued_update_fn cb,
+ void *cb_data);
+
/*
* Free `*transaction` and all associated data.
*/
There is no way for a caller to see whether a reference update has already been queued up for a given reference transaction. There are multiple alternatives to provide this functionality: - We may add a function that simply tells us whether a specific reference has already been queued. If implemented naively then this would potentially be quadratic in runtime behaviour if this question is asked repeatedly because we have to iterate over all references every time. The alternative would be to add a hashmap of all queued reference updates to speed up the lookup, but this adds overhead to all callers. - We may add a flag to `ref_transaction_add_update()` that causes it to skip duplicates, but this has the same runtime concerns as the first alternative. - We may add an interface which lets callers collect all updates which have already been queued such that he can avoid re-adding them. This is the most flexible approach and puts the burden on the caller, but also allows us to not impact any of the existing callsites which don't need this information. This commit implements the last approach: it allows us to compute the map of already-queued updates once up front such that we can then skip all subsequent references which are already part of this map. Signed-off-by: Patrick Steinhardt <ps@pks.im> --- refs.c | 16 ++++++++++++++++ refs.h | 14 ++++++++++++++ 2 files changed, 30 insertions(+)