git-annex/Command/Repair.hs
Joey Hess ce045a51af Improve repair of git-annex index file.
Fixes a test case I received where a corrupted repo was repaired, but the
git-annex branch was not. The root of the problem was that the
MissingObject returned by the repair code was not necessarily a complete
set of all objects that might have been deleted during the repair.

So, stop trying to return that at all, and instead make the index file
checking code explicitly verify that each object the index uses is present.
2013-12-10 15:40:01 -04:00

69 lines
2.4 KiB
Haskell

{- git-annex command
-
- Copyright 2013 Joey Hess <joey@kitenet.net>
-
- Licensed under the GNU GPL version 3 or higher.
-}
module Command.Repair where
import Common.Annex
import Command
import qualified Annex
import qualified Git.Repair
import qualified Annex.Branch
import Git.Types
import Annex.Version
def :: [Command]
def = [noCommit $ dontCheck repoExists $
command "repair" paramNothing seek SectionMaintenance "recover broken git repository"]
seek :: [CommandSeek]
seek = [withNothing start]
start :: CommandStart
start = next $ next $ runRepair =<< Annex.getState Annex.force
runRepair :: Bool -> Annex Bool
runRepair forced = do
(ok, modifiedbranches) <- inRepo $
Git.Repair.runRepair forced
-- This command can be run in git repos not using git-annex,
-- so avoid git annex branch stuff in that case.
whenM (isJust <$> getVersion) $
repairAnnexBranch modifiedbranches
return ok
{- After git repository repair, the .git/annex/index file could
- still be broken, by pointing to bad objects, or might just be corrupt on
- its own. Since this index file is not used to stage things
- for long durations of time, it can safely be deleted if it is broken.
-
- Otherwise, if the git-annex branch was modified by the repair,
- commit the index file to the git-annex branch.
- This way, if the git-annex branch got rewound to an old version by
- the repository repair, or was completely deleted, this will get it back
- to a good state. Note that in the unlikely case where the git-annex
- branch was rewound to a state that, had new changes from elsewhere not
- yet reflected in the index, this does properly merge those into the
- index before committing.
-}
repairAnnexBranch :: [Branch] -> Annex ()
repairAnnexBranch modifiedbranches
| Annex.Branch.fullname `elem` modifiedbranches = ifM okindex
( commitindex
, do
nukeindex
liftIO $ putStrLn "Had to delete the .git/annex/index file as it was corrupt. Since the git-annex branch is not up-to-date anymore. It would be a very good idea to run: git annex fsck --fast"
)
| otherwise = ifM okindex
( noop
, nukeindex
)
where
okindex = Annex.Branch.withIndex $ inRepo $ Git.Repair.checkIndex
commitindex = do
Annex.Branch.forceCommit "committing index after git repository repair"
liftIO $ putStrLn "Successfully recovered the git-annex branch using .git/annex/index"
nukeindex = inRepo $ nukeFile . gitAnnexIndex