[PATCH v2] sha1-file: remove OBJECT_INFO_SKIP_CACHED
- From
- Jonathan Tan <jonathantanmy@google.com>
- Date
- Jan 2, 2020, 20:16 UTC
- Message-ID
- <20200102201630.180969-1-jonathantanmy@google.com>
- In-Reply-To
- <20191230211027.37002-1-jonathantanmy@google.com>
In a partial clone, if a user provides the hash of the empty tree ("git mktree </dev/null" - for SHA-1, this is 4b825d...) to a command which requires that that object be parsed, for example:
git diff-tree 4b825d <a non-empty tree>
then Git will lazily fetch the empty tree, unnecessarily, because parsing of that object invokes repo_has_object_file(), which does not special-case the empty tree.
Instead, teach repo_has_object_file() to consult find_cached_object() (which handles the empty tree), thus bringing it in line with the rest of the object-store-accessing functions. A cost is that repo_has_object_file() will now need to oideq upon each invocation, but that is trivial compared to the filesystem lookup or the pack index search required anyway. (And if find_cached_object() needs to do more because of previous invocations to pretend_object_file(), all the more reason to be consistent in whether we present cached objects.)
As a historical note, the function now known as repo_read_object_file() was taught the empty tree in 346245a1bb ("hard-code the empty tree object", 2008-02-13), and the function now known as oid_object_info() was taught the empty tree in c4d9986f5f ("sha1_object_info: examine cached_object store too", 2011-02-07). repo_has_object_file() was never updated, perhaps due to oversight. The flag OBJECT_INFO_SKIP_CACHED, introduced later in dfdd4afcf9 ("sha1_file: teach sha1_object_info_extended more flags", 2017-06-26) and used in e83e71c5e1 ("sha1_file: refactor has_sha1_file_with_flags", 2017-06-26), was introduced to preserve this difference in empty-tree handling, but now it can be removed.
Signed-off-by: Jonathan Tan <jonathantanmy@google.com> --- Forgot to add v2 to the other email, so resending it with the correct email subject.
Difference from v1: updated commit message in response to Jonathan Nieder's feedback. Hopefully I didn't remove too much. --- object-store.h | 2 -- sha1-file.c | 38 ++++++++++++++++++-------------------- 2 files changed, 18 insertions(+), 22 deletions(-)
diff --git a/object-store.h b/object-store.h index 55ee639350..61b8b13e3b 100644 --- a/object-store.h +++ b/object-store.h @@ -292,8 +292,6 @@ struct object_info { #define OBJECT_INFO_LOOKUP_REPLACE 1 /* Allow reading from a loose object file of unknown/bogus type */ #define OBJECT_INFO_ALLOW_UNKNOWN_TYPE 2 -/* Do not check cached storage */ -#define OBJECT_INFO_SKIP_CACHED 4 /* Do not retry packed storage after checking packed and loose storage */ #define OBJECT_INFO_QUICK 8 /* Do not check loose object */ diff --git a/sha1-file.c b/sha1-file.c index 188de57634..03ae9ae93a 100644 --- a/sha1-file.c +++ b/sha1-file.c @@ -1417,6 +1417,7 @@ int oid_object_info_extended(struct repository *r, const struct object_id *oid, struct object_info *oi, unsigned flags) { static struct object_info blank_oi = OBJECT_INFO_INIT; + struct cached_object *co; struct pack_entry e; int rtype; const struct object_id *real = oid; @@ -1431,24 +1432,22 @@ int oid_object_info_extended(struct repository *r, const struct object_id *oid, if (!oi) oi = &blank_oi; - if (!(flags & OBJECT_INFO_SKIP_CACHED)) { - struct cached_object *co = find_cached_object(real); - if (co) { - if (oi->typep) - *(oi->typep) = co->type; - if (oi->sizep) - *(oi->sizep) = co->size; - if (oi->disk_sizep) - *(oi->disk_sizep) = 0; - if (oi->delta_base_sha1) - hashclr(oi->delta_base_sha1); - if (oi->type_name) - strbuf_addstr(oi->type_name, type_name(co->type)); - if (oi->contentp) - *oi->contentp = xmemdupz(co->buf, co->size); - oi->whence = OI_CACHED; - return 0; - } + co = find_cached_object(real); + if (co) { + if (oi->typep) + *(oi->typep) = co->type; + if (oi->sizep) + *(oi->sizep) = co->size; + if (oi->disk_sizep) + *(oi->disk_sizep) = 0; + if (oi->delta_base_sha1) + hashclr(oi->delta_base_sha1); + if (oi->type_name) + strbuf_addstr(oi->type_name, type_name(co->type)); + if (oi->contentp) + *oi->contentp = xmemdupz(co->buf, co->size); + oi->whence = OI_CACHED; + return 0; } while (1) { @@ -1932,8 +1931,7 @@ int repo_has_object_file_with_flags(struct repository *r, { if (!startup_info->have_repository) return 0; - return oid_object_info_extended(r, oid, NULL, - flags | OBJECT_INFO_SKIP_CACHED) >= 0; + return oid_object_info_extended(r, oid, NULL, flags) >= 0; } int repo_has_object_file(struct repository *r,
-- 2.24.1.735.g03f4e72817-goog