From: Karthik Nayak Date: Tue, 8 Apr 2025 08:51:11 +0000 (+0200) Subject: refs: support rejection in batch updates during F/D checks X-Git-Tag: v2.50.0-rc0~104^2~1 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=31726bb90d70236f7afaa345bf45195e2ef62d22;p=thirdparty%2Fgit.git refs: support rejection in batch updates during F/D checks The `refs_verify_refnames_available()` is used to batch check refnames for F/D conflicts. While this is the more performant alternative than its individual version, it does not provide rejection capabilities on a single update level. For batched updates, this would mean a rejection of the entire transaction whenever one reference has a F/D conflict. Modify the function to call `ref_transaction_maybe_set_rejected()` to check if a single update can be rejected. Since this function is only internally used within 'refs/' and we want to pass in a `struct ref_transaction *` as a variable. We also move and mark `refs_verify_refnames_available()` to 'refs-internal.h' to be an internal function. Signed-off-by: Karthik Nayak Acked-by: Patrick Steinhardt Signed-off-by: Junio C Hamano --- diff --git a/refs.c b/refs.c index 6edc79262a..498aec3fc0 100644 --- a/refs.c +++ b/refs.c @@ -2540,6 +2540,7 @@ enum ref_transaction_error refs_verify_refnames_available(struct ref_store *refs const struct string_list *refnames, const struct string_list *extras, const struct string_list *skip, + struct ref_transaction *transaction, unsigned int initial_transaction, struct strbuf *err) { @@ -2547,6 +2548,7 @@ enum ref_transaction_error refs_verify_refnames_available(struct ref_store *refs struct strbuf referent = STRBUF_INIT; struct string_list_item *item; struct ref_iterator *iter = NULL; + struct strset conflicting_dirnames; struct strset dirnames; int ret = REF_TRANSACTION_ERROR_NAME_CONFLICT; @@ -2557,9 +2559,11 @@ enum ref_transaction_error refs_verify_refnames_available(struct ref_store *refs assert(err); + strset_init(&conflicting_dirnames); strset_init(&dirnames); for_each_string_list_item(item, refnames) { + const size_t *update_idx = (size_t *)item->util; const char *refname = item->string; const char *extra_refname; struct object_id oid; @@ -2597,14 +2601,30 @@ enum ref_transaction_error refs_verify_refnames_available(struct ref_store *refs continue; if (!initial_transaction && - !refs_read_raw_ref(refs, dirname.buf, &oid, &referent, - &type, &ignore_errno)) { + (strset_contains(&conflicting_dirnames, dirname.buf) || + !refs_read_raw_ref(refs, dirname.buf, &oid, &referent, + &type, &ignore_errno))) { + if (transaction && ref_transaction_maybe_set_rejected( + transaction, *update_idx, + REF_TRANSACTION_ERROR_NAME_CONFLICT)) { + strset_remove(&dirnames, dirname.buf); + strset_add(&conflicting_dirnames, dirname.buf); + continue; + } + strbuf_addf(err, _("'%s' exists; cannot create '%s'"), dirname.buf, refname); goto cleanup; } if (extras && string_list_has_string(extras, dirname.buf)) { + if (transaction && ref_transaction_maybe_set_rejected( + transaction, *update_idx, + REF_TRANSACTION_ERROR_NAME_CONFLICT)) { + strset_remove(&dirnames, dirname.buf); + continue; + } + strbuf_addf(err, _("cannot process '%s' and '%s' at the same time"), refname, dirname.buf); goto cleanup; @@ -2637,6 +2657,11 @@ enum ref_transaction_error refs_verify_refnames_available(struct ref_store *refs string_list_has_string(skip, iter->refname)) continue; + if (transaction && ref_transaction_maybe_set_rejected( + transaction, *update_idx, + REF_TRANSACTION_ERROR_NAME_CONFLICT)) + continue; + strbuf_addf(err, _("'%s' exists; cannot create '%s'"), iter->refname, refname); goto cleanup; @@ -2648,6 +2673,11 @@ enum ref_transaction_error refs_verify_refnames_available(struct ref_store *refs extra_refname = find_descendant_ref(dirname.buf, extras, skip); if (extra_refname) { + if (transaction && ref_transaction_maybe_set_rejected( + transaction, *update_idx, + REF_TRANSACTION_ERROR_NAME_CONFLICT)) + continue; + strbuf_addf(err, _("cannot process '%s' and '%s' at the same time"), refname, extra_refname); goto cleanup; @@ -2659,6 +2689,7 @@ enum ref_transaction_error refs_verify_refnames_available(struct ref_store *refs cleanup: strbuf_release(&referent); strbuf_release(&dirname); + strset_clear(&conflicting_dirnames); strset_clear(&dirnames); ref_iterator_free(iter); return ret; @@ -2679,7 +2710,7 @@ enum ref_transaction_error refs_verify_refname_available( }; return refs_verify_refnames_available(refs, &refnames, extras, skip, - initial_transaction, err); + NULL, initial_transaction, err); } struct do_for_each_reflog_help { diff --git a/refs.h b/refs.h index 43f2041edf..67a9b2c454 100644 --- a/refs.h +++ b/refs.h @@ -141,18 +141,6 @@ enum ref_transaction_error refs_verify_refname_available(struct ref_store *refs, unsigned int initial_transaction, struct strbuf *err); -/* - * Same as `refs_verify_refname_available()`, but checking for a list of - * refnames instead of only a single item. This is more efficient in the case - * where one needs to check multiple refnames. - */ -enum ref_transaction_error refs_verify_refnames_available(struct ref_store *refs, - const struct string_list *refnames, - const struct string_list *extras, - const struct string_list *skip, - unsigned int initial_transaction, - struct strbuf *err); - int refs_ref_exists(struct ref_store *refs, const char *refname); int should_autocreate_reflog(enum log_refs_config log_all_ref_updates, diff --git a/refs/files-backend.c b/refs/files-backend.c index 9620dd86fb..8b20e40401 100644 --- a/refs/files-backend.c +++ b/refs/files-backend.c @@ -677,16 +677,18 @@ static void unlock_ref(struct ref_lock *lock) * - Generate informative error messages in the case of failure */ static enum ref_transaction_error lock_raw_ref(struct files_ref_store *refs, - const char *refname, + struct ref_update *update, + size_t update_idx, int mustexist, struct string_list *refnames_to_check, const struct string_list *extras, struct ref_lock **lock_p, struct strbuf *referent, - unsigned int *type, struct strbuf *err) { enum ref_transaction_error ret = REF_TRANSACTION_ERROR_GENERIC; + const char *refname = update->refname; + unsigned int *type = &update->type; struct ref_lock *lock; struct strbuf ref_file = STRBUF_INIT; int attempts_remaining = 3; @@ -785,6 +787,8 @@ retry: if (files_read_raw_ref(&refs->base, refname, &lock->old_oid, referent, type, &failure_errno)) { + struct string_list_item *item; + if (failure_errno == ENOENT) { if (mustexist) { /* Garden variety missing reference. */ @@ -864,7 +868,9 @@ retry: * make sure there is no existing packed ref that conflicts * with refname. This check is deferred so that we can batch it. */ - string_list_append(refnames_to_check, refname); + item = string_list_append(refnames_to_check, refname); + item->util = xmalloc(sizeof(update_idx)); + memcpy(item->util, &update_idx, sizeof(update_idx)); } ret = 0; @@ -2547,6 +2553,7 @@ struct files_transaction_backend_data { */ static enum ref_transaction_error lock_ref_for_update(struct files_ref_store *refs, struct ref_update *update, + size_t update_idx, struct ref_transaction *transaction, const char *head_ref, struct string_list *refnames_to_check, @@ -2575,9 +2582,9 @@ static enum ref_transaction_error lock_ref_for_update(struct files_ref_store *re if (lock) { lock->count++; } else { - ret = lock_raw_ref(refs, update->refname, mustexist, + ret = lock_raw_ref(refs, update, update_idx, mustexist, refnames_to_check, &transaction->refnames, - &lock, &referent, &update->type, err); + &lock, &referent, err); if (ret) { char *reason; @@ -2849,7 +2856,7 @@ static int files_transaction_prepare(struct ref_store *ref_store, for (i = 0; i < transaction->nr; i++) { struct ref_update *update = transaction->updates[i]; - ret = lock_ref_for_update(refs, update, transaction, + ret = lock_ref_for_update(refs, update, i, transaction, head_ref, &refnames_to_check, err); if (ret) { @@ -2905,7 +2912,8 @@ static int files_transaction_prepare(struct ref_store *ref_store, * So instead, we accept the race for now. */ if (refs_verify_refnames_available(refs->packed_ref_store, &refnames_to_check, - &transaction->refnames, NULL, 0, err)) { + &transaction->refnames, NULL, transaction, + 0, err)) { ret = REF_TRANSACTION_ERROR_NAME_CONFLICT; goto cleanup; } @@ -2951,7 +2959,7 @@ static int files_transaction_prepare(struct ref_store *ref_store, cleanup: free(head_ref); - string_list_clear(&refnames_to_check, 0); + string_list_clear(&refnames_to_check, 1); if (ret) files_transaction_cleanup(refs, transaction); @@ -3097,7 +3105,8 @@ static int files_transaction_finish_initial(struct files_ref_store *refs, } if (refs_verify_refnames_available(&refs->base, &refnames_to_check, - &affected_refnames, NULL, 1, err)) { + &affected_refnames, NULL, transaction, + 1, err)) { packed_refs_unlock(refs->packed_ref_store); ret = REF_TRANSACTION_ERROR_NAME_CONFLICT; goto cleanup; diff --git a/refs/refs-internal.h b/refs/refs-internal.h index 73a5379b73..f868870851 100644 --- a/refs/refs-internal.h +++ b/refs/refs-internal.h @@ -806,4 +806,20 @@ enum ref_transaction_error ref_update_check_old_target(const char *referent, */ int ref_update_expects_existing_old_ref(struct ref_update *update); +/* + * Same as `refs_verify_refname_available()`, but checking for a list of + * refnames instead of only a single item. This is more efficient in the case + * where one needs to check multiple refnames. + * + * If using batched updates, then individual updates are marked rejected, + * reference backends are then in charge of not committing those updates. + */ +enum ref_transaction_error refs_verify_refnames_available(struct ref_store *refs, + const struct string_list *refnames, + const struct string_list *extras, + const struct string_list *skip, + struct ref_transaction *transaction, + unsigned int initial_transaction, + struct strbuf *err); + #endif /* REFS_REFS_INTERNAL_H */ diff --git a/refs/reftable-backend.c b/refs/reftable-backend.c index 8fb7d6cc71..a461d1b8e0 100644 --- a/refs/reftable-backend.c +++ b/refs/reftable-backend.c @@ -1074,6 +1074,7 @@ static enum ref_transaction_error prepare_single_update(struct reftable_ref_stor struct ref_transaction *transaction, struct reftable_backend *be, struct ref_update *u, + size_t update_idx, struct string_list *refnames_to_check, unsigned int head_type, struct strbuf *head_referent, @@ -1149,6 +1150,7 @@ static enum ref_transaction_error prepare_single_update(struct reftable_ref_stor if (ret < 0) return REF_TRANSACTION_ERROR_GENERIC; if (ret > 0 && !ref_update_expects_existing_old_ref(u)) { + struct string_list_item *item; /* * The reference does not exist, and we either have no * old object ID or expect the reference to not exist. @@ -1158,7 +1160,9 @@ static enum ref_transaction_error prepare_single_update(struct reftable_ref_stor * can output a proper error message instead of failing * at a later point. */ - string_list_append(refnames_to_check, u->refname); + item = string_list_append(refnames_to_check, u->refname); + item->util = xmalloc(sizeof(update_idx)); + memcpy(item->util, &update_idx, sizeof(update_idx)); /* * There is no need to write the reference deletion @@ -1368,7 +1372,7 @@ static int reftable_be_transaction_prepare(struct ref_store *ref_store, for (i = 0; i < transaction->nr; i++) { ret = prepare_single_update(refs, tx_data, transaction, be, - transaction->updates[i], + transaction->updates[i], i, &refnames_to_check, head_type, &head_referent, &referent, err); if (ret) { @@ -1384,6 +1388,7 @@ static int reftable_be_transaction_prepare(struct ref_store *ref_store, ret = refs_verify_refnames_available(ref_store, &refnames_to_check, &transaction->refnames, NULL, + transaction, transaction->flags & REF_TRANSACTION_FLAG_INITIAL, err); if (ret < 0) @@ -1402,7 +1407,7 @@ done: } strbuf_release(&referent); strbuf_release(&head_referent); - string_list_clear(&refnames_to_check, 0); + string_list_clear(&refnames_to_check, 1); return ret; }