From bdbebe5714b25dc9d215b48efbb80f410925d7dd Mon Sep 17 00:00:00 2001 From: Patrick Steinhardt Date: Thu, 23 Oct 2025 09:16:10 +0200 Subject: refs: introduce wrapper struct for `each_ref_fn` The `each_ref_fn` callback function type is used across our code base for several different functions that iterate through reference. There's a bunch of callbacks implementing this type, which makes any changes to the callback signature extremely noisy. An example of the required churn is e8207717f1 (refs: add referent to each_ref_fn, 2024-08-09): adding a single argument required us to change 48 files. It was already proposed back then [1] that we might want to introduce a wrapper structure to alleviate the pain going forward. While this of course requires the same kind of global refactoring as just introducing a new parameter, it at least allows us to more change the callback type afterwards by just extending the wrapper structure. One counterargument to this refactoring is that it makes the structure more opaque. While it is obvious which callsites need to be fixed up when we change the function type, it's not obvious anymore once we use a structure. That being said, we only have a handful of sites that actually need to populate this wrapper structure: our ref backends, "refs/iterator.c" as well as very few sites that invoke the iterator callback functions directly. Introduce this wrapper structure so that we can adapt the iterator interfaces more readily. [1]: Signed-off-by: Patrick Steinhardt Signed-off-by: Junio C Hamano --- commit-graph.c | 14 ++++++-------- 1 file changed, 6 insertions(+), 8 deletions(-) (limited to 'commit-graph.c') diff --git a/commit-graph.c b/commit-graph.c index 474454db73..f91af41625 100644 --- a/commit-graph.c +++ b/commit-graph.c @@ -1851,18 +1851,16 @@ struct refs_cb_data { struct progress *progress; }; -static int add_ref_to_set(const char *refname UNUSED, - const char *referent UNUSED, - const struct object_id *oid, - int flags UNUSED, void *cb_data) +static int add_ref_to_set(const struct reference *ref, void *cb_data) { + const struct object_id *maybe_peeled = ref->oid; struct object_id peeled; struct refs_cb_data *data = (struct refs_cb_data *)cb_data; - if (!peel_iterated_oid(data->repo, oid, &peeled)) - oid = &peeled; - if (odb_read_object_info(data->repo->objects, oid, NULL) == OBJ_COMMIT) - oidset_insert(data->commits, oid); + if (!peel_iterated_oid(data->repo, ref->oid, &peeled)) + maybe_peeled = &peeled; + if (odb_read_object_info(data->repo->objects, maybe_peeled, NULL) == OBJ_COMMIT) + oidset_insert(data->commits, maybe_peeled); display_progress(data->progress, oidset_size(data->commits)); -- cgit v1.2.3 From f89866163704528f1a6570e134853dbb99120e7c Mon Sep 17 00:00:00 2001 From: Patrick Steinhardt Date: Thu, 23 Oct 2025 09:16:14 +0200 Subject: refs: expose peeled object ID via the iterator Both the "files" and "reftable" backend are able to store peeled values for tags in the respective formats. This allows for a more efficient lookup of the target object of such a tag without having to manually peel via the object database. The infrastructure to access these peeled object IDs is somewhat funky though. When iterating through objects, we store a pointer reference to the current iterator in a global variable. The callbacks invoked by that iterator are then expected to call `peel_iterated_oid()`, which checks whether the globally-stored iterator's current reference refers to the one handed into that function. If so, we ask the iterator to peel the object, otherwise we manually peel the object via the object database. Depending on global state like this is somewhat weird and also quite fragile. Introduce a new `struct reference::peeled_oid` field that can be populated by the reference backends. This field can be accessed via a new function `reference_get_peeled_oid()` that either uses that value, if set, or alternatively peels via the ODB. With this change we don't have to rely on global state anymore, but make the peeled object ID available to the callback functions directly. Adjust trivial callers that already have a `struct reference` available. Remaining callers will be adjusted in subsequent commits. Signed-off-by: Patrick Steinhardt Signed-off-by: Junio C Hamano --- builtin/describe.c | 2 +- builtin/gc.c | 2 +- builtin/pack-objects.c | 7 ++++--- commit-graph.c | 2 +- ls-refs.c | 2 +- midx-write.c | 2 +- pseudo-merge.c | 2 +- refs.c | 12 ++++++++++++ refs.h | 19 +++++++++++++++++++ refs/packed-backend.c | 1 + refs/reftable-backend.c | 5 +++++ repack-midx.c | 2 +- 12 files changed, 48 insertions(+), 10 deletions(-) (limited to 'commit-graph.c') diff --git a/builtin/describe.c b/builtin/describe.c index 7954535044..443546aaac 100644 --- a/builtin/describe.c +++ b/builtin/describe.c @@ -208,7 +208,7 @@ static int get_name(const struct reference *ref, void *cb_data UNUSED) } /* Is it annotated? */ - if (!peel_iterated_oid(the_repository, ref->oid, &peeled)) { + if (!reference_get_peeled_oid(the_repository, ref, &peeled)) { is_annotated = !oideq(ref->oid, &peeled); } else { oidcpy(&peeled, ref->oid); diff --git a/builtin/gc.c b/builtin/gc.c index 9de5de175f..f0cf20d423 100644 --- a/builtin/gc.c +++ b/builtin/gc.c @@ -1109,7 +1109,7 @@ static int dfs_on_ref(const struct reference *ref, void *cb_data) struct commit_list *stack = NULL; struct commit *commit; - if (!peel_iterated_oid(the_repository, ref->oid, &peeled)) + if (!reference_get_peeled_oid(the_repository, ref, &peeled)) maybe_peeled = &peeled; if (odb_read_object_info(the_repository->objects, maybe_peeled, NULL) != OBJ_COMMIT) return 0; diff --git a/builtin/pack-objects.c b/builtin/pack-objects.c index 39633a0158..1613fecb66 100644 --- a/builtin/pack-objects.c +++ b/builtin/pack-objects.c @@ -838,7 +838,7 @@ static int mark_tagged(const struct reference *ref, void *cb_data UNUSED) if (entry) entry->tagged = 1; - if (!peel_iterated_oid(the_repository, ref->oid, &peeled)) { + if (!reference_get_peeled_oid(the_repository, ref, &peeled)) { entry = packlist_find(&to_pack, &peeled); if (entry) entry->tagged = 1; @@ -3309,7 +3309,8 @@ static int add_ref_tag(const struct reference *ref, void *cb_data UNUSED) { struct object_id peeled; - if (!peel_iterated_oid(the_repository, ref->oid, &peeled) && obj_is_packed(&peeled)) + if (!reference_get_peeled_oid(the_repository, ref, &peeled) && + obj_is_packed(&peeled)) add_tag_chain(ref->oid); return 0; } @@ -4537,7 +4538,7 @@ static int mark_bitmap_preferred_tip(const struct reference *ref, void *data UNU struct object_id peeled; struct object *object; - if (!peel_iterated_oid(the_repository, ref->oid, &peeled)) + if (!reference_get_peeled_oid(the_repository, ref, &peeled)) maybe_peeled = &peeled; object = parse_object_or_die(the_repository, maybe_peeled, ref->name); diff --git a/commit-graph.c b/commit-graph.c index f91af41625..80be2ff2c3 100644 --- a/commit-graph.c +++ b/commit-graph.c @@ -1857,7 +1857,7 @@ static int add_ref_to_set(const struct reference *ref, void *cb_data) struct object_id peeled; struct refs_cb_data *data = (struct refs_cb_data *)cb_data; - if (!peel_iterated_oid(data->repo, ref->oid, &peeled)) + if (!reference_get_peeled_oid(data->repo, ref, &peeled)) maybe_peeled = &peeled; if (odb_read_object_info(data->repo->objects, maybe_peeled, NULL) == OBJ_COMMIT) oidset_insert(data->commits, maybe_peeled); diff --git a/ls-refs.c b/ls-refs.c index 64d0272369..8641281b86 100644 --- a/ls-refs.c +++ b/ls-refs.c @@ -110,7 +110,7 @@ static int send_ref(const struct reference *ref, void *cb_data) if (data->peel && ref->oid) { struct object_id peeled; - if (!peel_iterated_oid(the_repository, ref->oid, &peeled)) + if (!reference_get_peeled_oid(the_repository, ref, &peeled)) strbuf_addf(&data->buf, " peeled:%s", oid_to_hex(&peeled)); } diff --git a/midx-write.c b/midx-write.c index f4dd875747..23e61cb000 100644 --- a/midx-write.c +++ b/midx-write.c @@ -709,7 +709,7 @@ static int add_ref_to_pending(const struct reference *ref, void *cb_data) return 0; } - if (!peel_iterated_oid(revs->repo, ref->oid, &peeled)) + if (!reference_get_peeled_oid(revs->repo, ref, &peeled)) maybe_peeled = &peeled; object = parse_object_or_die(revs->repo, maybe_peeled, ref->name); diff --git a/pseudo-merge.c b/pseudo-merge.c index 0abd51b42c..a2d5bd85f9 100644 --- a/pseudo-merge.c +++ b/pseudo-merge.c @@ -230,7 +230,7 @@ static int find_pseudo_merge_group_for_ref(const struct reference *ref, void *_d uint32_t i; int has_bitmap; - if (!peel_iterated_oid(the_repository, ref->oid, &peeled)) + if (!reference_get_peeled_oid(the_repository, ref, &peeled)) maybe_peeled = &peeled; c = lookup_commit(the_repository, maybe_peeled); diff --git a/refs.c b/refs.c index f96cf43b12..1b1551f981 100644 --- a/refs.c +++ b/refs.c @@ -2334,6 +2334,18 @@ int peel_iterated_oid(struct repository *r, const struct object_id *base, struct return peel_object(r, base, peeled) ? -1 : 0; } +int reference_get_peeled_oid(struct repository *repo, + const struct reference *ref, + struct object_id *peeled_oid) +{ + if (ref->peeled_oid) { + oidcpy(peeled_oid, ref->peeled_oid); + return 0; + } + + return peel_object(repo, ref->oid, peeled_oid) ? -1 : 0; +} + int refs_update_symref(struct ref_store *refs, const char *ref, const char *target, const char *logmsg) { diff --git a/refs.h b/refs.h index 4f0a685714..886ed2c0f4 100644 --- a/refs.h +++ b/refs.h @@ -371,10 +371,29 @@ struct reference { */ const struct object_id *oid; + /* + * An optional peeled object ID. This field _may_ be set for tags in + * case the peeled value is present in the backend. Please refer to + * `reference_get_peeled_oid()`. + */ + const struct object_id *peeled_oid; + /* A bitfield of `enum reference_status` flags. */ unsigned flags; }; +/* + * Peel the tag to a non-tag commit. If present, this uses the peeled object ID + * exposed by the reference backend. Otherwise, the object is peeled via the + * object database, which is less efficient. + * + * Return `0` if the reference could be peeled, a negative error code + * otherwise. + */ +int reference_get_peeled_oid(struct repository *repo, + const struct reference *ref, + struct object_id *peeled_oid); + /* * The signature for the callback function for the for_each_*() * functions below. The memory pointed to by the `struct reference` diff --git a/refs/packed-backend.c b/refs/packed-backend.c index 711e07f832..1fefefd54e 100644 --- a/refs/packed-backend.c +++ b/refs/packed-backend.c @@ -963,6 +963,7 @@ static int next_record(struct packed_ref_iterator *iter) iter->base.ref.flags &= ~REF_KNOWS_PEELED; } else { iter->base.ref.flags |= REF_KNOWS_PEELED; + iter->base.ref.peeled_oid = &iter->peeled; } } else { oidclr(&iter->peeled, iter->repo->hash_algo); diff --git a/refs/reftable-backend.c b/refs/reftable-backend.c index 728886eafd..e214e120d7 100644 --- a/refs/reftable-backend.c +++ b/refs/reftable-backend.c @@ -547,6 +547,7 @@ struct reftable_ref_iterator { struct reftable_iterator iter; struct reftable_ref_record ref; struct object_id oid; + struct object_id peeled_oid; char *prefix; size_t prefix_len; @@ -671,6 +672,8 @@ static int reftable_ref_iterator_advance(struct ref_iterator *ref_iterator) case REFTABLE_REF_VAL2: oidread(&iter->oid, iter->ref.value.val2.value, refs->base.repo->hash_algo); + oidread(&iter->peeled_oid, iter->ref.value.val2.target_value, + refs->base.repo->hash_algo); break; case REFTABLE_REF_SYMREF: referent = refs_resolve_ref_unsafe(&iter->refs->base, @@ -708,6 +711,8 @@ static int reftable_ref_iterator_advance(struct ref_iterator *ref_iterator) iter->base.ref.name = iter->ref.refname; iter->base.ref.target = referent; iter->base.ref.oid = &iter->oid; + if (iter->ref.value_type == REFTABLE_REF_VAL2) + iter->base.ref.peeled_oid = &iter->peeled_oid; iter->base.ref.flags = flags; break; diff --git a/repack-midx.c b/repack-midx.c index 349f7e20b5..74bdfa3a6e 100644 --- a/repack-midx.c +++ b/repack-midx.c @@ -22,7 +22,7 @@ static int midx_snapshot_ref_one(const struct reference *ref, void *_data) const struct object_id *maybe_peeled = ref->oid; struct object_id peeled; - if (!peel_iterated_oid(data->repo, ref->oid, &peeled)) + if (!reference_get_peeled_oid(data->repo, ref, &peeled)) maybe_peeled = &peeled; if (oidset_insert(&data->seen, maybe_peeled)) -- cgit v1.2.3