git-annex/Database/Fsck.hs

106 lines
2.9 KiB
Haskell

{- Sqlite database used for incremental fsck.
-
- Copyright 2015 Joey Hess <id@joeyh.name>
-:
- Licensed under the GNU GPL version 3 or higher.
-}
{-# LANGUAGE QuasiQuotes, TypeFamilies, TemplateHaskell #-}
{-# LANGUAGE OverloadedStrings, GADTs, FlexibleContexts #-}
{-# LANGUAGE MultiParamTypeClasses, GeneralizedNewtypeDeriving #-}
{-# LANGUAGE RankNTypes #-}
module Database.Fsck (
FsckHandle,
newPass,
openDb,
closeDb,
addDb,
inDb,
FsckedId,
) where
import Database.Types
import qualified Database.Queue as H
import Annex.Locations
import Utility.PosixFiles
import Utility.Exception
import Annex.Common
import Annex.Perms
import Annex.LockFile
import Database.Persist.TH
import Database.Esqueleto hiding (Key)
import Data.Time.Clock
data FsckHandle = FsckHandle H.DbQueue UUID
{- Each key stored in the database has already been fscked as part
- of the latest incremental fsck pass. -}
share [mkPersist sqlSettings, mkMigrate "migrateFsck"] [persistLowerCase|
Fscked
key SKey
UniqueKey key
|]
{- The database is removed when starting a new incremental fsck pass.
-
- This may fail, if other fsck processes are currently running using the
- database. Removing the database in that situation would lead to crashes
- or unknown behavior.
-}
newPass :: UUID -> Annex Bool
newPass u = isJust <$> tryExclusiveLock (gitAnnexFsckDbLock u) go
where
go = liftIO . void . tryIO . removeDirectoryRecursive
=<< fromRepo (gitAnnexFsckDbDir u)
{- Opens the database, creating it if it doesn't exist yet. -}
openDb :: UUID -> Annex FsckHandle
openDb u = do
dbdir <- fromRepo (gitAnnexFsckDbDir u)
let db = dbdir </> "db"
unlessM (liftIO $ doesFileExist db) $ do
let tmpdbdir = dbdir ++ ".tmp"
let tmpdb = tmpdbdir </> "db"
liftIO $ do
createDirectoryIfMissing True tmpdbdir
H.initDb tmpdb $ void $
runMigrationSilent migrateFsck
setAnnexDirPerm tmpdbdir
setAnnexFilePerm tmpdb
liftIO $ do
void $ tryIO $ removeDirectoryRecursive dbdir
rename tmpdbdir dbdir
lockFileCached =<< fromRepo (gitAnnexFsckDbLock u)
h <- liftIO $ H.openDbQueue db "fscked"
return $ FsckHandle h u
closeDb :: FsckHandle -> Annex ()
closeDb (FsckHandle h u) = do
liftIO $ H.closeDbQueue h
unlockFile =<< fromRepo (gitAnnexFsckDbLock u)
addDb :: FsckHandle -> Key -> IO ()
addDb (FsckHandle h _) k = H.queueDb h checkcommit $
void $ insertUnique $ Fscked sk
where
sk = toSKey k
-- commit queue after 1000 files or 5 minutes, whichever comes first
checkcommit sz lastcommittime
| sz > 1000 = return True
| otherwise = do
now <- getCurrentTime
return $ diffUTCTime lastcommittime now > 300
{- Doesn't know about keys that were just added with addDb. -}
inDb :: FsckHandle -> Key -> IO Bool
inDb (FsckHandle h _) = H.queryDbQueue h . inDb' . toSKey
inDb' :: SKey -> SqlPersistM Bool
inDb' sk = do
r <- select $ from $ \r -> do
where_ (r ^. FsckedKey ==. val sk)
return (r ^. FsckedKey)
return $ not $ null r