git-annex/Command/ReKey.hs
Joey Hess 3a05d53761
add SeekInput (not yet used)
No behavior changes (hopefully), just adding SeekInput and plumbing it
through to the JSON display code for later use.

Over the course of 2 grueling days.

withFilesNotInGit reimplemented in terms of seekHelper
should be the only possible behavior change. It seems to test as
behaving the same.

Note that seekHelper dummies up the SeekInput in the case where
segmentPaths' gives up on sorting the expanded paths because there are
too many input paths. When SeekInput later gets exposed as a json field,
that will result in it being a little bit wrong in the case where
100 or more paths are passed to a git-annex command. I think this is a
subtle enough problem to not matter. If it does turn out to be a
problem, fixing it would require splitting up the input
parameters into groups of < 100, which would make git ls-files run
perhaps more than is necessary. May want to revisit this, because that
fix seems fairly low-impact.
2020-09-15 15:41:13 -04:00

138 lines
4.4 KiB
Haskell

{- git-annex command
-
- Copyright 2012-2016 Joey Hess <id@joeyh.name>
-
- Licensed under the GNU AGPL version 3 or higher.
-}
module Command.ReKey where
import Command
import qualified Annex
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
import qualified Utility.RawFilePath as R
cmd :: Command
cmd = command "rekey" SectionPlumbing
"change keys used for files"
(paramRepeating $ paramPair paramPath paramKey)
(seek <$$> optParser)
data ReKeyOptions = ReKeyOptions
{ reKeyThese :: CmdParams
, batchOption :: BatchMode
}
optParser :: CmdParamsDesc -> Parser ReKeyOptions
optParser desc = ReKeyOptions
<$> cmdParams desc
<*> parseBatchOption
-- Split on the last space, since a FilePath can contain whitespace,
-- but a Key very rarely does.
batchParser :: String -> Annex (Either String (RawFilePath, Key))
batchParser s = case separate (== ' ') (reverse s) of
(rk, rf)
| null rk || null rf -> return $ Left "Expected: \"file key\""
| otherwise -> case deserializeKey (reverse rk) of
Nothing -> return $ Left "bad key"
Just k -> do
let f = reverse rf
f' <- liftIO $ relPathCwdToFile f
return $ Right (toRawFilePath f', k)
seek :: ReKeyOptions -> CommandSeek
seek o = case batchOption o of
Batch fmt -> batchInput fmt batchParser
(batchCommandAction . uncurry start)
NoBatch -> withPairs
(\(si, p) -> commandAction (start si (parsekey p)))
(reKeyThese o)
where
parsekey (file, skey) =
(toRawFilePath file, fromMaybe (giveup "bad key") (deserializeKey skey))
start :: SeekInput -> (RawFilePath, Key) -> CommandStart
start si (file, newkey) = ifAnnexed file go stop
where
go oldkey
| oldkey == newkey = stop
| otherwise = starting "rekey" ai si $
perform file oldkey newkey
ai = ActionItemWorkTreeFile file
perform :: RawFilePath -> Key -> Key -> CommandPerform
perform file oldkey newkey = do
ifM (inAnnex oldkey)
( unlessM (linkKey file oldkey newkey) $
giveup "failed creating link from old to new key"
, unlessM (Annex.getState Annex.force) $
giveup $ fromRawFilePath 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 :: RawFilePath -> 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 getViaTmpFromDisk, 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. -}
( getViaTmpFromDisk RetrievalAllKeysSecure DefaultVerify newkey $ \tmp -> unVerified $ do
oldobj <- fromRawFilePath <$> calcRepo (gitAnnexLocation oldkey)
isJust <$> linkOrCopy' (return True) newkey oldobj tmp Nothing
, do
{- The file being rekeyed is itself an unlocked file; if
- it's hard linked to the old key, that link must be broken. -}
oldobj <- fromRawFilePath <$> calcRepo (gitAnnexLocation oldkey)
v <- tryNonAsync $ do
st <- liftIO $ R.getFileStatus file
when (linkCount st > 1) $ do
freezeContent oldobj
replaceWorkTreeFile (fromRawFilePath file) $ \tmp -> do
unlessM (checkedCopyFile oldkey oldobj tmp Nothing) $
error "can't lock old key"
thawContent tmp
ic <- withTSDelta (liftIO . genInodeCache file)
case v of
Left e -> do
warning (show e)
return False
Right () -> do
r <- linkToAnnex newkey (fromRawFilePath file) ic
return $ case r of
LinkAnnexFailed -> False
LinkAnnexOk -> True
LinkAnnexNoop -> True
)
cleanup :: RawFilePath -> Key -> Key -> CommandCleanup
cleanup file oldkey newkey = do
ifM (isJust <$> isAnnexLink file)
( do
-- Update symlink to use the new key.
liftIO $ removeFile (fromRawFilePath file)
addLink (fromRawFilePath file) newkey Nothing
, do
mode <- liftIO $ catchMaybeIO $ fileMode <$> R.getFileStatus file
liftIO $ whenM (isJust <$> isPointerFile file) $
writePointerFile file newkey mode
stagePointerFile file mode =<< hashPointerFile newkey
Database.Keys.removeAssociatedFile oldkey
=<< inRepo (toTopFilePath file)
)
whenM (inAnnex newkey) $
logStatus newkey InfoPresent
return True