The changes in commit c06793a4ed (allow git-bundle to create bottomless
bundle, 2007-08-08) ensure annotated tags are properly preserved when
creating a bundle using a revision range operation.
At the time the range notation would peel the ends to their
corresponding commit, meaning ref v2.0 would point to the v2.0^0 commit.
So the above workaround was introduced. This code looks up the ref
before it's written to the bundle, and if the ref doesn't point to the
object we expect (for tags this would be a tag object), we skip the ref
from the bundle. Instead, when the ref is a tag that's the positive end
of the range (e.g. v2.0 from the range "v1.0..v2.0"), then that ref is
written to the bundle instead.
Later, in 895c5ba3c1 (revision: do not peel tags used in range notation,
2013-09-19), the behavior of parsing ranges was changed and the problem
was fixed at the cause. But the workaround in bundle.c was not reverted.
Now it seems this workaround can cause a race condition. git-bundle(1)
uses setup_revisions() to parse the input into `struct rev_info`. Later,
in write_bundle_refs(), it uses this info to write refs to the bundle.
As mentioned at this point each ref is looked up again and checked
whether it points to the object we expect. If not, the ref is not
written to the bundle. But, when creating a bundle in a heavy traffic
repository (a repo with many references, and frequent ref updates) it's
possible a branch ref was updated between setup_revisions() and
write_bundle_refs() and thus the extra check causes the ref to be
skipped.
The workaround was originally added to deal with tags, but the code path
also gets hit by non-tag refs, causing this race condition. Because it's
no longer needed, remove it and fix the possible race condition.
Signed-off-by: Toon Claes <toon@iotcl.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Git - fast, scalable, distributed revision control system
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and full access to internals.
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See Documentation/gittutorial.txt to get started, then see
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If git has been correctly installed, then the tutorial can also be
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CVS users may also want to read Documentation/gitcvs-migration.txt
(man gitcvs-migration or git help cvs-migration if git is
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The name "git" was given by Linus Torvalds when he wrote the very
first version. He described the tool as "the stupid content tracker"
and the name as (depending on your mood):
random three-letter combination that is pronounceable, and not
actually used by any common UNIX command. The fact that it is a
mispronunciation of "get" may or may not be relevant.
stupid. contemptible and despicable. simple. Take your pick from the
dictionary of slang.
"global information tracker": you're in a good mood, and it actually
works for you. Angels sing, and a light suddenly fills the room.
"goddamn idiotic truckload of sh*t": when it breaks
