git-annex/Backend/VURL/Utilities.hs
Joey Hess 4ca3d1d584
remove read of the heads
and one tail

Removed head from Utility.PartialPrelude in order to avoid the build
warning with recent ghc versions as well.
2024-09-26 18:43:59 -04:00

58 lines
1.8 KiB
Haskell

{- git-annex VURL backend utilities
-
- Copyright 2024 Joey Hess <id@joeyh.name>
-
- Licensed under the GNU AGPL version 3 or higher.
-}
module Backend.VURL.Utilities where
import Annex.Common
import Types.Key
import Types.Backend
import Types.KeySource
import Logs.EquivilantKeys
import qualified Backend.Hash
import Utility.Metered
migrateFromURLToVURL :: Key -> Backend -> AssociatedFile -> Bool -> Annex (Maybe Key)
migrateFromURLToVURL oldkey newbackend _af inannex
| inannex && fromKey keyVariety oldkey == URLKey && backendVariety newbackend == VURLKey = do
let newkey = mkKey $ const $
(keyData oldkey)
{ keyVariety = VURLKey }
contentfile <- calcRepo (gitAnnexLocation oldkey)
generateEquivilantKey hashbackend contentfile >>= \case
Nothing -> return Nothing
Just ek -> do
setEquivilantKey newkey ek
return (Just newkey)
| otherwise = return Nothing
where
-- Relies on the first hash being cryptographically secure, and the
-- default hash used by git-annex.
hashbackend = fromMaybe (error "internal") $
headMaybe Backend.Hash.backends
migrateFromVURLToURL :: Key -> Backend -> AssociatedFile -> Bool -> Annex (Maybe Key)
migrateFromVURLToURL oldkey newbackend _af _
| fromKey keyVariety oldkey == VURLKey && backendVariety newbackend == URLKey =
return $ Just $ mkKey $ const $
(keyData oldkey)
{ keyVariety = URLKey }
| otherwise = return Nothing
-- The Backend must use a cryptographically secure hash.
generateEquivilantKey :: Backend -> RawFilePath -> Annex (Maybe Key)
generateEquivilantKey b f =
case genKey b of
Just genkey -> do
showSideAction (UnquotedString Backend.Hash.descChecksum)
Just <$> genkey source nullMeterUpdate
Nothing -> return Nothing
where
source = KeySource
{ keyFilename = mempty -- avoid adding any extension
, contentLocation = f
, inodeCache = Nothing
}