Re: git-repack -a -d produces unusable packs with 1.4.0
Thomas Glanzmann <sithglan@stud.uni-erlangen.de> writes:
> Pack pack-ce49d2efd5af06ed6093049050b5ba41da8b683f created.
> mv: overwrite `.git/objects/pack/pack-ce49d2efd5af06ed6093049050b5ba41da8b683f.pack', overriding mode 0444? y
> mv: overwrite `.git/objects/pack/pack-ce49d2efd5af06ed6093049050b5ba41da8b683f.idx', overriding mode 0444? y
> fatal: packfile .git/objects/pack/pack-ce49d2efd5af06ed6093049050b5ba41da8b683f.pack does not match index.
I would understand if you answer 'y' to one but 'n' to the other it would result in a situation with unmatching .pack and .idx and you would see something like the above (by the way, the "fatal" is coming from update-server-info that tries to read from freshly moved packfiles); but the above is different, so it does not explain the symptom. I am worried and curious as to what happened, since you are answering 'y' to both of them. This would trigger immediately after a clone which creates pack and idx unwritable; repack leaves the results writable unless your umask is 0222, so "mv" would not even ask the silly questions.
Did you happen to have .tmp-pack-ce49d2ef... at the project root level after this failure? If so which one (either .pack or .idx)?
If you had .tmp-pack-*.pack then .git/objects/pack/pack-ce49...pack is from the old round and .git/objects/pack/pack-ce49...idx is from the new one. Moving .tmp-pack-* to .git/objects/pack/pack-* would hopefully solve this problem.
Nevertheless, this _is_ a dangerous and grave bug, and thanks for reporting it.
Maybe we would want to do something like this:
-- >8 -- git-repack: Be careful when updating the same pack as existing one.
After clone, packfiles are read-only by default and "mv" went interactive asking if the user wants to replace it with a repacked copy. If one is successfully moved and the other is not, the pack and its idx would become out-of-sync and corrupts the repository.
Recovering is straightforward -- it is just the matter of finding the remaining .tmp-pack-* and make sure they are both moved -- but we should be extra careful not to do something so alarming to the users.
---
diff --git a/git-repack.sh b/git-repack.sh
index eb75c8c..b58cf91 100755
--- a/git-repack.sh
+++ b/git-repack.sh
@@ -54,9 +54,21 @@ else
fi
mkdir -p "$PACKDIR" || exit
- mv .tmp-pack-$name.pack "$PACKDIR/pack-$name.pack" &&
- mv .tmp-pack-$name.idx "$PACKDIR/pack-$name.idx" ||
- exit
+ for sfx in pack idx
+ do
+ if test -f "$PACKDIR/pack-$name.$sfx"
+ then
+ mv -f "$PACKDIR/pack-$name.$sfx" "$PACKDIR/old-pack-$name.$sfx"
+ fi
+ done
+ mv -f .tmp-pack-$name.pack "$PACKDIR/pack-$name.pack" &&
+ mv -f .tmp-pack-$name.idx "$PACKDIR/pack-$name.idx" || {
+ echo >&2 "Couldn't replace the existing pack with updated one."
+ echo >&2 "The original set of packs have been saved as"
+ echo >&2 "old-pack-$name.{pack,idx} in $PACKDIR."
+ exit 1
+ }
+ rm -f "$PACKDIR/old-pack-$name.pack" "$PACKDIR/old-pack-$name.idx"
fi
if test "$remove_redundant" = t
