[PATCH v2 2/5] setup: detangle loading of loose object maps
From: Patrick Steinhardt <hidden>
Date: 2026-08-04 08:30:03
Subsystem:
the rest · Maintainer:
Linus Torvalds
When a repository is configured to use a compatibility hash function
then we load the loose object map when we initialize the repository.
This object map provides the mappings between the canonical object hash
and the compatibility object hash.
Loading the object map happens in `repo_set_compat_hash_algo()`, which
calls `repo_read_loose_object_map()` in case the compatibility object
hash is non-zero. This setup sequence has two major downsides:
- We assume that the primary object database is the "files" object
database and unconditionally downcast it. This will cause us to BUG
in case a different object database type was used together with a
compat hash algorithm.
- We require the object database to already have been initialized when
configuring the object database. This means that we must intermix
configuration of the repository and initialization of its
sub-structures in a weird way.
Refactor the logic so that we instead load the loose object map via the
"loose" backend, which fixes both of the above issues.
Signed-off-by: Patrick Steinhardt <redacted>
---
loose.c | 11 +++++------
loose.h | 1 +
odb/source-loose.c | 2 ++
repository.c | 2 --
setup.c | 5 +++--
5 files changed, 11 insertions(+), 10 deletions(-)
diff --git a/loose.c b/loose.c
index 9dad75373b..a3b2dcedc2 100644
--- a/loose.c
+++ b/loose.c@@ -61,7 +61,7 @@ static int insert_loose_map(struct odb_source_loose *loose, return inserted; } -static int load_one_loose_object_map(struct odb_source_loose *loose) +int loose_object_map_load(struct odb_source_loose *loose) { struct repository *repo = loose->base.odb->repo; struct strbuf buf = STRBUF_INIT;
@@ -69,6 +69,9 @@ static int load_one_loose_object_map(struct odb_source_loose *loose) FILE *fp; int ret = -1; + if (!should_use_loose_object_map(repo)) + return 0; + if (!loose->map) loose_object_map_init(&loose->map); if (!loose->cache) {
@@ -112,14 +115,10 @@ int repo_read_loose_object_map(struct repository *repo) { struct odb_source *source; - if (!should_use_loose_object_map(repo)) - return 0; - odb_prepare_alternates(repo->objects); - for (source = repo->objects->sources; source; source = source->next) { struct odb_source_files *files = odb_source_files_downcast(source); - if (load_one_loose_object_map(files->loose) < 0) + if (loose_object_map_load(files->loose) < 0) return -1; }
diff --git a/loose.h b/loose.h
index 6c9b3f4571..ed663ac550 100644
--- a/loose.h
+++ b/loose.h@@ -13,6 +13,7 @@ struct loose_object_map { void loose_object_map_init(struct loose_object_map **map); void loose_object_map_clear(struct loose_object_map **map); +int loose_object_map_load(struct odb_source_loose *loose); int repo_loose_object_map_oid(struct repository *repo, const struct object_id *src, const struct git_hash_algo *dest_algo,
diff --git a/odb/source-loose.c b/odb/source-loose.c
index 3f7d04a56e..812ca1c138 100644
--- a/odb/source-loose.c
+++ b/odb/source-loose.c@@ -727,5 +727,7 @@ struct odb_source_loose *odb_source_loose_new(struct object_database *odb, if (!is_absolute_path(loose->base.path)) chdir_notify_register(NULL, odb_source_loose_reparent, loose); + loose_object_map_load(loose); + return loose; }
diff --git a/repository.c b/repository.c
index 2ef0778846..6d633002b4 100644
--- a/repository.c
+++ b/repository.c@@ -201,8 +201,6 @@ void repo_set_compat_hash_algo(struct repository *repo MAYBE_UNUSED, uint32_t al if (hash_algo_by_ptr(repo->hash_algo) == algo) BUG("hash_algo and compat_hash_algo match"); repo->compat_hash_algo = algo ? &hash_algos[algo] : NULL; - if (repo->compat_hash_algo) - repo_read_loose_object_map(repo); #else if (algo) die(_("compatibility hash algorithm support requires Rust"));
diff --git a/setup.c b/setup.c
index d31808130b..825572f5f1 100644
--- a/setup.c
+++ b/setup.c@@ -1788,8 +1788,6 @@ int apply_repository_format(struct repository *repo, repo->bare_cfg = format->is_bare; repo_set_hash_algo(repo, format->hash_algo); - repo->objects = odb_new(repo, object_directory, - alternate_object_directories); repo_set_compat_hash_algo(repo, format->compat_hash_algo); repo_set_ref_storage_format(repo, format->ref_storage_format,
@@ -1805,6 +1803,9 @@ int apply_repository_format(struct repository *repo, repo->repository_format_precious_objects = format->precious_objects; + repo->objects = odb_new(repo, object_directory, + alternate_object_directories); + free(alternate_object_directories); free(object_directory); return 0;
--
2.55.0.679.g6767b8d81c.dirty