During update_refs we will both be deleting refs as well as updating/changing
the refs.
Since both delete and update now use the same lock/update/commit pattern
lock = lock_ref_sha1_basic() (or varient of)
write_ref_sha1(lock)/delete_ref_loose(lock)
unlock_ref(lock) | commit_ref_lock(lock)
we can now simplify update_update refs to have one loop that locks all
involved refs.
A second loop that writes or flags for deletion, but does not commit, all
the refs.
And a final third loop that commits all the refs once all the work and
preparations are complete.
This makes updating/deleting multiple refs 'more atomic' since we will not start
the commit phase until all the preparations have completed successfully.
Signed-off-by: Ronnie Sahlberg <sahlb...@google.com>
---
refs.c | 30 ++++++++++++++----------------
1 file changed, 14 insertions(+), 16 deletions(-)
diff --git a/refs.c b/refs.c
index 038614d..e94099b 100644
--- a/refs.c
+++ b/refs.c
@@ -3369,33 +3369,31 @@ int update_refs(const char *action, const struct
ref_update **updates_orig,
}
/* Perform updates first so live commits remain referenced */
- for (i = 0; i < n; i++)
- if (!is_null_sha1(updates[i]->new_sha1)) {
+ for (i = 0; i < n; i++) {
+ if (!is_null_sha1(updates[i]->new_sha1))
ret = update_ref_write(action,
updates[i]->ref_name,
updates[i]->new_sha1,
locks[i], onerr);
- if (ret)
- unlock_ref(locks[i]);
- else
- commit_ref_lock(locks[i]);
- locks[i] = NULL;
- if (ret)
- goto cleanup;
+ else {
+ delnames[delnum++] = locks[i]->ref_name;
+ ret = delete_ref_loose(locks[i], types[i]);
}
+ if (ret)
+ goto cleanup;
+ }
- /* Perform deletes now that updates are safely completed */
+ ret = repack_without_refs(delnames, delnum);
+ for (i = 0; i < delnum; i++)
+ unlink_or_warn(git_path("logs/%s", delnames[i]));
+ clear_loose_ref_cache(&ref_cache);
+
+ /* Commit all the updates/deletions */
for (i = 0; i < n; i++)
if (locks[i]) {
- delnames[delnum++] = locks[i]->ref_name;
- ret |= delete_ref_loose(locks[i], types[i]);
ret |= commit_ref_lock(locks[i]);
locks[i] = NULL;
}
- ret |= repack_without_refs(delnames, delnum);
- for (i = 0; i < delnum; i++)
- unlink_or_warn(git_path("logs/%s", delnames[i]));
- clear_loose_ref_cache(&ref_cache);
cleanup:
for (i = 0; i < n; i++)
--
1.9.1.477.g7668a0d.dirty
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