summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorJeff King <peff@peff.net>2020-04-10 03:04:11 (GMT)
committerJunio C Hamano <gitster@pobox.com>2020-04-10 05:40:48 (GMT)
commit022046107186746913ef43a33f4b6862817bf6da (patch)
tree8771b6579f937b523921e6630e1c2dc279b8e893
parent5ff4b920ebeadfa640f1b7d5929f58bb180a0519 (diff)
downloadgit-022046107186746913ef43a33f4b6862817bf6da.zip
git-022046107186746913ef43a33f4b6862817bf6da.tar.gz
git-022046107186746913ef43a33f4b6862817bf6da.tar.bz2
repository: mark the "refs" pointer as private
The "refs" pointer in a struct repository starts life as NULL, but then is lazily initialized when it is accessed via get_main_ref_store(). However, it's easy for calling code to forget this and access it directly, leading to code which works _some_ of the time, but fails if it is called before anybody else accesses the refs. This was the cause of the bug fixed by 5ff4b920eb (sha1-name: do not assume that the ref store is initialized, 2020-04-09). In order to prevent similar bugs, let's more clearly mark the "refs" field as private. In addition to helping future code, the name change will help us audit any existing direct uses. Besides get_main_ref_store() itself, it turns out there is only one. But we know it's OK as it is on the line directly after the fix from 5ff4b920eb, which will have initialized the pointer. However it's still a good idea for it to model the proper use of the accessing function, so we'll convert it. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
-rw-r--r--refs.c8
-rw-r--r--repository.h8
-rw-r--r--sha1-name.c2
3 files changed, 11 insertions, 7 deletions
diff --git a/refs.c b/refs.c
index 92d1f6d..4cc32e7 100644
--- a/refs.c
+++ b/refs.c
@@ -1774,14 +1774,14 @@ static struct ref_store *ref_store_init(const char *gitdir,
struct ref_store *get_main_ref_store(struct repository *r)
{
- if (r->refs)
- return r->refs;
+ if (r->refs_private)
+ return r->refs_private;
if (!r->gitdir)
BUG("attempting to get main_ref_store outside of repository");
- r->refs = ref_store_init(r->gitdir, REF_STORE_ALL_CAPS);
- return r->refs;
+ r->refs_private = ref_store_init(r->gitdir, REF_STORE_ALL_CAPS);
+ return r->refs_private;
}
/*
diff --git a/repository.h b/repository.h
index 4fb6a58..4ecc201 100644
--- a/repository.h
+++ b/repository.h
@@ -39,8 +39,12 @@ struct repository {
*/
struct parsed_object_pool *parsed_objects;
- /* The store in which the refs are held. */
- struct ref_store *refs;
+ /*
+ * The store in which the refs are held. This should generally only be
+ * accessed via get_main_ref_store(), as that will lazily initialize
+ * the ref object.
+ */
+ struct ref_store *refs_private;
/*
* Contains path to often used file names.
diff --git a/sha1-name.c b/sha1-name.c
index 3aba629..c679e24 100644
--- a/sha1-name.c
+++ b/sha1-name.c
@@ -1772,7 +1772,7 @@ static enum get_oid_result get_oid_with_context_1(struct repository *repo,
cb.repo = repo;
cb.list = &list;
refs_for_each_ref(get_main_ref_store(repo), handle_one_ref, &cb);
- refs_head_ref(repo->refs, handle_one_ref, &cb);
+ refs_head_ref(get_main_ref_store(repo), handle_one_ref, &cb);
commit_list_sort_by_date(&list);
return get_oid_oneline(repo, name + 2, oid, list);
}