[PATCH v2 1/4] sha1-file: introduce no-lazy-fetch has_object()
- From
- Jonathan Tan <jonathantanmy@google.com>
- Date
- Aug 5, 2020, 23:06 UTC
- Message-ID
- <f413b34574a330030e08a6eb93ad812975959d7d.1596668156.git.jonathantanmy@google.com>
- In-Reply-To
- <cover.1596668156.git.jonathantanmy@google.com>
There have been a few bugs wherein Git fetches missing objects whenever the existence of an object is checked, even though it does not need to perform such a fetch. To resolve these bugs, we could look at all the places that has_object_file() (or a similar function) is used. As a first step, introduce a new function has_object() that checks for the existence of an object, with a default behavior of not fetching if the object is missing and the repository is a partial clone. As we verify each has_object_file() (or similar) usage, we can replace it with has_object(), and we will know that we are done when we can delete has_object_file() (and the other similar functions).
Also, the new function has_object() has more appropriate defaults: besides not fetching, it also does not recheck packed storage.
Signed-off-by: Jonathan Tan <jonathantanmy@google.com> --- object-store.h | 25 +++++++++++++++++++++++-- sha1-file.c | 12 ++++++++++++ 2 files changed, 35 insertions(+), 2 deletions(-)
diff --git a/object-store.h b/object-store.h index f439d47af8..c4fc9dd74e 100644 --- a/object-store.h +++ b/object-store.h @@ -239,12 +239,33 @@ int read_loose_object(const char *path, unsigned long *size, void **contents); +/* Retry packed storage after checking packed and loose storage */ +#define HAS_OBJECT_RECHECK_PACKED 1 + +/* + * Returns 1 if the object exists. This function will not lazily fetch objects + * in a partial clone. + */ +int has_object(struct repository *r, const struct object_id *oid, + unsigned flags); + +/* + * These macros and functions are deprecated. If checking existence for an + * object that is likely to be missing and/or whose absence is relatively + * inconsequential (or is consequential but the caller is prepared to handle + * it), use has_object(), which has better defaults (no lazy fetch in a partial + * clone and no rechecking of packed storage). In the unlikely event that a + * caller needs to assert existence of an object that it fully expects to + * exist, and wants to trigger a lazy fetch in a partial clone, use + * oid_object_info_extended() with a NULL struct object_info. + * + * These functions can be removed once all callers have migrated to + * has_object() and/or oid_object_info_extended(). + */ #ifndef NO_THE_REPOSITORY_COMPATIBILITY_MACROS #define has_sha1_file_with_flags(sha1, flags) repo_has_sha1_file_with_flags(the_repository, sha1, flags) #define has_sha1_file(sha1) repo_has_sha1_file(the_repository, sha1) #endif - -/* Same as the above, except for struct object_id. */ int repo_has_object_file(struct repository *r, const struct object_id *oid); int repo_has_object_file_with_flags(struct repository *r, const struct object_id *oid, int flags); diff --git a/sha1-file.c b/sha1-file.c index ccd34dd9e8..ff444d7abb 100644 --- a/sha1-file.c +++ b/sha1-file.c @@ -1988,6 +1988,18 @@ int force_object_loose(const struct object_id *oid, time_t mtime) return ret; } +int has_object(struct repository *r, const struct object_id *oid, + unsigned flags) +{ + int quick = !(flags & HAS_OBJECT_RECHECK_PACKED); + unsigned object_info_flags = OBJECT_INFO_SKIP_FETCH_OBJECT | + (quick ? OBJECT_INFO_QUICK : 0); + + if (!startup_info->have_repository) + return 0; + return oid_object_info_extended(r, oid, NULL, object_info_flags) >= 0; +} + int repo_has_object_file_with_flags(struct repository *r, const struct object_id *oid, int flags) {
-- 2.28.0.236.gb10cc79966-goog