git-annex/Command/ReKey.hs
Joey Hess d6fe7fdd7d
rekey: No longer copies over urls from the old to the new key.
It makes sense for migrate to do that, but not for this low-level (and
little used) plumbing command to.
2016-01-07 18:06:20 -04:00

108 lines
3.1 KiB
Haskell

{- git-annex command
-
- Copyright 2012-2016 Joey Hess <id@joeyh.name>
-
- Licensed under the GNU GPL version 3 or higher.
-}
module Command.ReKey where
import Common.Annex
import Command
import qualified Annex
import Types.Key
import Annex.Content
import Annex.Ingest
import Annex.Link
import Annex.Perms
import Annex.ReplaceFile
import Logs.Location
import Git.FilePath
import qualified Database.Keys
import Annex.InodeSentinal
import Utility.InodeCache
cmd :: Command
cmd = notDirect $
command "rekey" SectionPlumbing
"change keys used for files"
(paramRepeating $ paramPair paramPath paramKey)
(withParams seek)
seek :: CmdParams -> CommandSeek
seek = withPairs start
start :: (FilePath, String) -> CommandStart
start (file, keyname) = ifAnnexed file go stop
where
newkey = fromMaybe (error "bad key") $ file2key keyname
go oldkey
| oldkey == newkey = stop
| otherwise = do
showStart "rekey" file
next $ perform file oldkey newkey
perform :: FilePath -> Key -> Key -> CommandPerform
perform file oldkey newkey = do
ifM (inAnnex oldkey)
( unlessM (linkKey file oldkey newkey) $
error "failed"
, unlessM (Annex.getState Annex.force) $
error $ file ++ " is not available (use --force to override)"
)
next $ cleanup file oldkey newkey
{- Make a hard link to the old key content (when supported),
- to avoid wasting disk space. -}
linkKey :: FilePath -> Key -> Key -> Annex Bool
linkKey file oldkey newkey = ifM (isJust <$> isAnnexLink file)
{- If the object file is already hardlinked to elsewhere, a hard
- link won't be made by getViaTmp', but a copy instead.
- This avoids hard linking to content linked to an
- unlocked file, which would leave the new key unlocked
- and vulnerable to corruption. -}
( getViaTmp' DefaultVerify newkey $ \tmp -> unVerified $ do
oldobj <- calcRepo (gitAnnexLocation oldkey)
linkOrCopy' (return True) newkey oldobj tmp
, do
ic <- withTSDelta (liftIO . genInodeCache file)
{- The file being rekeyed is itself an unlocked file, so if
- it's linked to the old key, that link must be broken. -}
oldobj <- calcRepo (gitAnnexLocation oldkey)
v <- tryNonAsync $ modifyContent oldobj $ do
replaceFile oldobj $ \tmp ->
unlessM (checkedCopyFile oldkey file tmp) $
error "can't lock old key"
freezeContent oldobj
oldic <- withTSDelta (liftIO . genInodeCache oldobj)
whenM (isUnmodified oldkey oldobj) $
Database.Keys.addInodeCaches oldkey (catMaybes [oldic])
case v of
Left e -> do
warning (show e)
return False
Right () -> do
r <- linkToAnnex newkey file ic
return $ case r of
LinkAnnexFailed -> False
LinkAnnexOk -> True
LinkAnnexNoop -> True
)
cleanup :: FilePath -> Key -> Key -> CommandCleanup
cleanup file oldkey newkey = do
ifM (isJust <$> isAnnexLink file)
( do
-- Update symlink to use the new key.
liftIO $ removeFile file
addLink file newkey Nothing
, do
liftIO $ whenM (isJust <$> isPointerFile file) $
writeFile file (formatPointer newkey)
stagePointerFile file =<< hashPointerFile newkey
Database.Keys.removeAssociatedFile oldkey
=<< inRepo (toTopFilePath file)
)
logStatus newkey InfoPresent
return True