7bb93896af
directory: When cp supports reflinks, use it when getting content from a directory special remote. Not yet for imports from directory though, and not for store. Note that, when it's chunked, using cp --reflink would not speed it up, and when reflink was not supported, would unnecessarily write the chunk to a file before reading it back in. So, only using a fileRetriever in the NoChunks case is necessary to keep chunking fast. fileCopier is told not to verify, because the special remote interface does not yet support verification in passing. AFAICS, fileCopies can never return False when not verifying so the added giveup should never actually happen.
534 lines
19 KiB
Haskell
534 lines
19 KiB
Haskell
{- A "remote" that is just a filesystem directory.
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-
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- Copyright 2011-2021 Joey Hess <id@joeyh.name>
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-
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- Licensed under the GNU AGPL version 3 or higher.
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-}
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{-# LANGUAGE OverloadedStrings #-}
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{-# LANGUAGE CPP #-}
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module Remote.Directory (
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remote,
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finalizeStoreGeneric,
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removeDirGeneric,
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) where
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import qualified Data.ByteString.Lazy as L
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import qualified Data.Map as M
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import qualified System.FilePath.ByteString as P
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import Data.Default
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import Annex.Common
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import Types.Remote
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import Types.Export
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import Types.Creds
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import qualified Git
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import Config.Cost
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import Config
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import Annex.SpecialRemote.Config
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import Remote.Helper.Special
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import Remote.Helper.ExportImport
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import Types.Import
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import qualified Remote.Directory.LegacyChunked as Legacy
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import Annex.CopyFile
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import Annex.Content
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import Annex.Perms
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import Annex.UUID
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import Backend
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import Types.KeySource
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import Types.ProposedAccepted
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import Utility.Metered
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import Utility.Tmp
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import Utility.InodeCache
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import Utility.FileMode
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import Utility.Directory.Create
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import qualified Utility.RawFilePath as R
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remote :: RemoteType
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remote = specialRemoteType $ RemoteType
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{ typename = "directory"
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, enumerate = const (findSpecialRemotes "directory")
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, generate = gen
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, configParser = mkRemoteConfigParser
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[ optionalStringParser directoryField
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(FieldDesc "(required) where the special remote stores data")
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]
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, setup = directorySetup
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, exportSupported = exportIsSupported
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, importSupported = importIsSupported
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, thirdPartyPopulated = False
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}
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directoryField :: RemoteConfigField
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directoryField = Accepted "directory"
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gen :: Git.Repo -> UUID -> RemoteConfig -> RemoteGitConfig -> RemoteStateHandle -> Annex (Maybe Remote)
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gen r u rc gc rs = do
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c <- parsedRemoteConfig remote rc
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cst <- remoteCost gc cheapRemoteCost
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let chunkconfig = getChunkConfig c
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cow <- liftIO newCopyCoWTried
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return $ Just $ specialRemote c
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(storeKeyM dir chunkconfig)
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(retrieveKeyFileM dir chunkconfig cow)
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(removeKeyM dir)
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(checkPresentM dir chunkconfig)
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Remote
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{ uuid = u
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, cost = cst
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, name = Git.repoDescribe r
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, storeKey = storeKeyDummy
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, retrieveKeyFile = retrieveKeyFileDummy
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, retrieveKeyFileCheap = retrieveKeyFileCheapM dir chunkconfig
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, retrievalSecurityPolicy = RetrievalAllKeysSecure
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, removeKey = removeKeyDummy
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, lockContent = Nothing
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, checkPresent = checkPresentDummy
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, checkPresentCheap = True
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, exportActions = ExportActions
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{ storeExport = storeExportM dir
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, retrieveExport = retrieveExportM dir
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, removeExport = removeExportM dir
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, versionedExport = False
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, checkPresentExport = checkPresentExportM dir
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-- Not needed because removeExportLocation
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-- auto-removes empty directories.
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, removeExportDirectory = Nothing
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, renameExport = renameExportM dir
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}
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, importActions = ImportActions
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{ listImportableContents = listImportableContentsM dir
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, importKey = Just (importKeyM dir)
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, retrieveExportWithContentIdentifier = retrieveExportWithContentIdentifierM dir
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, storeExportWithContentIdentifier = storeExportWithContentIdentifierM dir
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, removeExportWithContentIdentifier = removeExportWithContentIdentifierM dir
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-- Not needed because removeExportWithContentIdentifier
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-- auto-removes empty directories.
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, removeExportDirectoryWhenEmpty = Nothing
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, checkPresentExportWithContentIdentifier = checkPresentExportWithContentIdentifierM dir
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}
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, whereisKey = Nothing
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, remoteFsck = Nothing
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, repairRepo = Nothing
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, config = c
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, getRepo = return r
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, gitconfig = gc
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, localpath = Just dir'
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, readonly = False
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, appendonly = False
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, untrustworthy = False
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, availability = LocallyAvailable
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, remotetype = remote
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, mkUnavailable = gen r u rc
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(gc { remoteAnnexDirectory = Just "/dev/null" }) rs
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, getInfo = return [("directory", dir')]
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, claimUrl = Nothing
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, checkUrl = Nothing
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, remoteStateHandle = rs
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}
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where
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dir = toRawFilePath dir'
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dir' = fromMaybe (giveup "missing directory") (remoteAnnexDirectory gc)
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directorySetup :: SetupStage -> Maybe UUID -> Maybe CredPair -> RemoteConfig -> RemoteGitConfig -> Annex (RemoteConfig, UUID)
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directorySetup _ mu _ c gc = do
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u <- maybe (liftIO genUUID) return mu
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-- verify configuration is sane
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let dir = maybe (giveup "Specify directory=") fromProposedAccepted $
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M.lookup directoryField c
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absdir <- liftIO $ fromRawFilePath <$> absPath (toRawFilePath dir)
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liftIO $ unlessM (doesDirectoryExist absdir) $
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giveup $ "Directory does not exist: " ++ absdir
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(c', _encsetup) <- encryptionSetup c gc
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-- The directory is stored in git config, not in this remote's
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-- persistant state, so it can vary between hosts.
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gitConfigSpecialRemote u c' [("directory", absdir)]
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return (M.delete directoryField c', u)
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{- Locations to try to access a given Key in the directory.
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- We try more than one since we used to write to different hash
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- directories. -}
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locations :: RawFilePath -> Key -> [RawFilePath]
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locations d k = map (d P.</>) (keyPaths k)
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{- Returns the location off a Key in the directory. If the key is
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- present, returns the location that is actually used, otherwise
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- returns the first, default location. -}
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getLocation :: RawFilePath -> Key -> IO RawFilePath
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getLocation d k = do
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let locs = locations d k
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fromMaybe (Prelude.head locs)
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<$> firstM (doesFileExist . fromRawFilePath) locs
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{- Directory where the file(s) for a key are stored. -}
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storeDir :: RawFilePath -> Key -> RawFilePath
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storeDir d k = P.addTrailingPathSeparator $
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d P.</> hashDirLower def k P.</> keyFile k
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{- Check if there is enough free disk space in the remote's directory to
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- store the key. Note that the unencrypted key size is checked. -}
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storeKeyM :: RawFilePath -> ChunkConfig -> Storer
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storeKeyM d chunkconfig k c m =
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ifM (checkDiskSpaceDirectory d k)
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( byteStorer (store d chunkconfig) k c m
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, giveup "Not enough free disk space."
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)
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checkDiskSpaceDirectory :: RawFilePath -> Key -> Annex Bool
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checkDiskSpaceDirectory d k = do
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annexdir <- fromRepo gitAnnexObjectDir
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samefilesystem <- liftIO $ catchDefaultIO False $
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(\a b -> deviceID a == deviceID b)
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<$> R.getFileStatus d
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<*> R.getFileStatus annexdir
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checkDiskSpace (Just d) k 0 samefilesystem
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store :: RawFilePath -> ChunkConfig -> Key -> L.ByteString -> MeterUpdate -> Annex ()
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store d chunkconfig k b p = liftIO $ do
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void $ tryIO $ createDirectoryUnder d tmpdir
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case chunkconfig of
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LegacyChunks chunksize ->
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Legacy.store
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(fromRawFilePath d)
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chunksize
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(finalizeStoreGeneric d)
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k b p
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(fromRawFilePath tmpdir)
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(fromRawFilePath destdir)
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_ -> do
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let tmpf = tmpdir P.</> kf
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meteredWriteFile p (fromRawFilePath tmpf) b
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finalizeStoreGeneric d tmpdir destdir
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where
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tmpdir = P.addTrailingPathSeparator $ d P.</> "tmp" P.</> kf
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kf = keyFile k
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destdir = storeDir d k
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{- Passed a temp directory that contains the files that should be placed
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- in the dest directory, moves it into place. Anything already existing
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- in the dest directory will be deleted. File permissions will be locked
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- down. -}
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finalizeStoreGeneric :: RawFilePath -> RawFilePath -> RawFilePath -> IO ()
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finalizeStoreGeneric d tmp dest = do
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removeDirGeneric (fromRawFilePath d) dest'
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createDirectoryUnder d (parentDir dest)
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renameDirectory (fromRawFilePath tmp) dest'
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-- may fail on some filesystems
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void $ tryIO $ do
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mapM_ (preventWrite . toRawFilePath) =<< dirContents dest'
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preventWrite dest
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where
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dest' = fromRawFilePath dest
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retrieveKeyFileM :: RawFilePath -> ChunkConfig -> CopyCoWTried -> Retriever
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retrieveKeyFileM d (LegacyChunks _) _ = Legacy.retrieve locations d
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retrieveKeyFileM d NoChunks cow = fileRetriever $ \dest k p -> do
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src <- liftIO $ fromRawFilePath <$> getLocation d k
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(ok, _verification) <- fileCopier cow src dest k p (return True) NoVerify
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unless ok $ giveup "failed to copy file from remote"
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retrieveKeyFileM d _ _ = byteRetriever $ \k sink ->
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sink =<< liftIO (L.readFile . fromRawFilePath =<< getLocation d k)
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retrieveKeyFileCheapM :: RawFilePath -> ChunkConfig -> Maybe (Key -> AssociatedFile -> FilePath -> Annex ())
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-- no cheap retrieval possible for chunks
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retrieveKeyFileCheapM _ (UnpaddedChunks _) = Nothing
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retrieveKeyFileCheapM _ (LegacyChunks _) = Nothing
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#ifndef mingw32_HOST_OS
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retrieveKeyFileCheapM d NoChunks = Just $ \k _af f -> liftIO $ do
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file <- fromRawFilePath <$> (absPath =<< getLocation d k)
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ifM (doesFileExist file)
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( createSymbolicLink file f
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, giveup "content file not present in remote"
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)
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#else
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retrieveKeyFileCheapM _ _ = Nothing
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#endif
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removeKeyM :: RawFilePath -> Remover
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removeKeyM d k = liftIO $ removeDirGeneric
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(fromRawFilePath d)
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(fromRawFilePath (storeDir d k))
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{- Removes the directory, which must be located under the topdir.
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-
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- Succeeds even on directories and contents that do not have write
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- permission, if it's possible to turn the write bit on.
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-
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- If the directory does not exist, succeeds as long as the topdir does
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- exist. If the topdir does not exist, fails, because in this case the
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- remote is not currently accessible and probably still has the content
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- we were supposed to remove from it.
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-}
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removeDirGeneric :: FilePath -> FilePath -> IO ()
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removeDirGeneric topdir dir = do
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void $ tryIO $ allowWrite (toRawFilePath dir)
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#ifdef mingw32_HOST_OS
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{- Windows needs the files inside the directory to be writable
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- before it can delete them. -}
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void $ tryIO $ mapM_ (allowWrite . toRawFilePath) =<< dirContents dir
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#endif
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tryNonAsync (removeDirectoryRecursive dir) >>= \case
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Right () -> return ()
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Left e ->
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unlessM (doesDirectoryExist topdir <&&> (not <$> doesDirectoryExist dir)) $
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throwM e
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checkPresentM :: RawFilePath -> ChunkConfig -> CheckPresent
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checkPresentM d (LegacyChunks _) k = Legacy.checkKey d locations k
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checkPresentM d _ k = checkPresentGeneric d (locations d k)
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checkPresentGeneric :: RawFilePath -> [RawFilePath] -> Annex Bool
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checkPresentGeneric d ps = checkPresentGeneric' d $
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liftIO $ anyM (doesFileExist . fromRawFilePath) ps
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checkPresentGeneric' :: RawFilePath -> Annex Bool -> Annex Bool
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checkPresentGeneric' d check = ifM check
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( return True
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, ifM (liftIO $ doesDirectoryExist (fromRawFilePath d))
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( return False
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, giveup $ "directory " ++ fromRawFilePath d ++ " is not accessible"
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)
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)
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storeExportM :: RawFilePath -> FilePath -> Key -> ExportLocation -> MeterUpdate -> Annex ()
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storeExportM d src _k loc p = liftIO $ do
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createDirectoryUnder d (P.takeDirectory dest)
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-- Write via temp file so that checkPresentGeneric will not
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-- see it until it's fully stored.
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viaTmp go (fromRawFilePath dest) ()
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where
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dest = exportPath d loc
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go tmp () = withMeteredFile src p (L.writeFile tmp)
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retrieveExportM :: RawFilePath -> Key -> ExportLocation -> FilePath -> MeterUpdate -> Annex ()
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retrieveExportM d _k loc dest p =
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liftIO $ withMeteredFile src p (L.writeFile dest)
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where
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src = fromRawFilePath $ exportPath d loc
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removeExportM :: RawFilePath -> Key -> ExportLocation -> Annex ()
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removeExportM d _k loc = liftIO $ do
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removeWhenExistsWith R.removeLink src
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removeExportLocation d loc
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where
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src = exportPath d loc
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checkPresentExportM :: RawFilePath -> Key -> ExportLocation -> Annex Bool
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checkPresentExportM d _k loc =
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checkPresentGeneric d [exportPath d loc]
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renameExportM :: RawFilePath -> Key -> ExportLocation -> ExportLocation -> Annex (Maybe ())
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renameExportM d _k oldloc newloc = liftIO $ do
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createDirectoryUnder d (P.takeDirectory dest)
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renameFile (fromRawFilePath src) (fromRawFilePath dest)
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removeExportLocation d oldloc
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return (Just ())
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where
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src = exportPath d oldloc
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dest = exportPath d newloc
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exportPath :: RawFilePath -> ExportLocation -> RawFilePath
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exportPath d loc = d P.</> fromExportLocation loc
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{- Removes the ExportLocation's parent directory and its parents, so long as
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- they're empty, up to but not including the topdir. -}
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removeExportLocation :: RawFilePath -> ExportLocation -> IO ()
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removeExportLocation topdir loc =
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go (Just $ P.takeDirectory $ fromExportLocation loc) (Right ())
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where
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go _ (Left _e) = return ()
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go Nothing _ = return ()
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go (Just loc') _ =
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let p = fromRawFilePath $ exportPath topdir $
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mkExportLocation loc'
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in go (upFrom loc') =<< tryIO (removeDirectory p)
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listImportableContentsM :: RawFilePath -> Annex (Maybe (ImportableContents (ContentIdentifier, ByteSize)))
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listImportableContentsM dir = liftIO $ do
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l <- dirContentsRecursive (fromRawFilePath dir)
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l' <- mapM (go . toRawFilePath) l
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return $ Just $ ImportableContents (catMaybes l') []
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where
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go f = do
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st <- R.getFileStatus f
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mkContentIdentifier f st >>= \case
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Nothing -> return Nothing
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Just cid -> do
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relf <- relPathDirToFile dir f
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sz <- getFileSize' f st
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return $ Just (mkImportLocation relf, (cid, sz))
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-- Make a ContentIdentifier that contains the size and mtime of the file.
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-- If the file is not a regular file, this will return Nothing.
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--
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-- The inode is zeroed because often this is used for import from a
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-- FAT filesystem, whose inodes change each time it's mounted, and
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-- including inodes would cause repeated re-hashing of files, and
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-- bloat the git-annex branch with changes to content identifier logs.
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--
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-- This does mean that swaps of two files with the same size and
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-- mtime won't be noticed, nor will modifications to files that
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-- preserve the size and mtime. Both very unlikely so acceptable.
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mkContentIdentifier :: RawFilePath -> FileStatus -> IO (Maybe ContentIdentifier)
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mkContentIdentifier f st =
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fmap (ContentIdentifier . encodeBS . showInodeCache)
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<$> toInodeCache' noTSDelta f st 0
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guardSameContentIdentifiers :: a -> ContentIdentifier -> Maybe ContentIdentifier -> a
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guardSameContentIdentifiers cont old new
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| new == Just old = cont
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| otherwise = giveup "file content has changed"
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importKeyM :: RawFilePath -> ExportLocation -> ContentIdentifier -> ByteSize -> MeterUpdate -> Annex (Maybe Key)
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importKeyM dir loc cid sz p = do
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backend <- chooseBackend f
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unsizedk <- fst <$> genKey ks p backend
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let k = alterKey unsizedk $ \kd -> kd
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{ keySize = keySize kd <|> Just sz }
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currcid <- liftIO $ mkContentIdentifier absf
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=<< R.getFileStatus absf
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guardSameContentIdentifiers (return (Just k)) cid currcid
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where
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f = fromExportLocation loc
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absf = dir P.</> f
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ks = KeySource
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{ keyFilename = f
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, contentLocation = absf
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, inodeCache = Nothing
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}
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retrieveExportWithContentIdentifierM :: RawFilePath -> ExportLocation -> ContentIdentifier -> FilePath -> Annex Key -> MeterUpdate -> Annex Key
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retrieveExportWithContentIdentifierM dir loc cid dest mkkey p =
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precheck $ docopy postcheck
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where
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f = exportPath dir loc
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f' = fromRawFilePath f
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docopy cont = do
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#ifndef mingw32_HOST_OS
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let open = do
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-- Need a duplicate fd for the post check, since
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-- hGetContentsMetered closes its handle.
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fd <- openFd f' ReadOnly Nothing defaultFileFlags
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dupfd <- dup fd
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h <- fdToHandle fd
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return (h, dupfd)
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let close (h, dupfd) = do
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hClose h
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closeFd dupfd
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bracketIO open close $ \(h, dupfd) -> do
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#else
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let open = openBinaryFile f' ReadMode
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let close = hClose
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bracketIO open close $ \h -> do
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#endif
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liftIO $ hGetContentsMetered h p >>= L.writeFile dest
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k <- mkkey
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#ifndef mingw32_HOST_OS
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cont dupfd (return k)
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#else
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cont (return k)
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#endif
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-- Check before copy, to avoid expensive copy of wrong file
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-- content.
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precheck cont = guardSameContentIdentifiers cont cid
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=<< liftIO . mkContentIdentifier f
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=<< liftIO (R.getFileStatus f)
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-- Check after copy, in case the file was changed while it was
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-- being copied.
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--
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-- When possible (not on Windows), check the same handle
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-- that the file was copied from. Avoids some race cases where
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-- the file is modified while it's copied but then gets restored
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-- to the original content afterwards.
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--
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-- This does not guard against every possible race, but neither
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-- can InodeCaches detect every possible modification to a file.
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-- It's probably as good or better than git's handling of similar
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-- situations with files being modified while it's updating the
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-- working tree for a merge.
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#ifndef mingw32_HOST_OS
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postcheck fd cont = do
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#else
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postcheck cont = do
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#endif
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currcid <- liftIO $ mkContentIdentifier f
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#ifndef mingw32_HOST_OS
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=<< getFdStatus fd
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#else
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=<< R.getFileStatus f
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#endif
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guardSameContentIdentifiers cont cid currcid
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storeExportWithContentIdentifierM :: RawFilePath -> FilePath -> Key -> ExportLocation -> [ContentIdentifier] -> MeterUpdate -> Annex ContentIdentifier
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storeExportWithContentIdentifierM dir src _k loc overwritablecids p = do
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liftIO $ createDirectoryUnder dir (toRawFilePath destdir)
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withTmpFileIn destdir template $ \tmpf tmph -> do
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let tmpf' = toRawFilePath tmpf
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liftIO $ withMeteredFile src p (L.hPut tmph)
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liftIO $ hFlush tmph
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liftIO $ hClose tmph
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resetAnnexFilePerm tmpf'
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liftIO (getFileStatus tmpf) >>= liftIO . mkContentIdentifier tmpf' >>= \case
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Nothing -> giveup "unable to generate content identifier"
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Just newcid -> do
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checkExportContent dir loc
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overwritablecids
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(giveup "unsafe to overwrite file")
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(const $ liftIO $ rename tmpf dest)
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return newcid
|
|
where
|
|
dest = fromRawFilePath $ exportPath dir loc
|
|
(destdir, base) = splitFileName dest
|
|
template = relatedTemplate (base ++ ".tmp")
|
|
|
|
removeExportWithContentIdentifierM :: RawFilePath -> Key -> ExportLocation -> [ContentIdentifier] -> Annex ()
|
|
removeExportWithContentIdentifierM dir k loc removeablecids =
|
|
checkExportContent dir loc removeablecids (giveup "unsafe to remove modified file") $ \case
|
|
DoesNotExist -> return ()
|
|
KnownContentIdentifier -> removeExportM dir k loc
|
|
|
|
checkPresentExportWithContentIdentifierM :: RawFilePath -> Key -> ExportLocation -> [ContentIdentifier] -> Annex Bool
|
|
checkPresentExportWithContentIdentifierM dir _k loc knowncids =
|
|
checkPresentGeneric' dir $
|
|
checkExportContent dir loc knowncids (return False) $ \case
|
|
DoesNotExist -> return False
|
|
KnownContentIdentifier -> return True
|
|
|
|
data CheckResult = DoesNotExist | KnownContentIdentifier
|
|
|
|
-- Checks if the content at an ExportLocation is in the knowncids,
|
|
-- and only runs the callback that modifies it if it's safe to do so.
|
|
--
|
|
-- This should avoid races to the extent possible. However,
|
|
-- if something has the file open for write, it could write to the handle
|
|
-- after the callback has overwritten or deleted it, and its write would
|
|
-- be lost, and we don't need to detect that.
|
|
-- (In similar situations, git doesn't either!)
|
|
--
|
|
-- It follows that if something is written to the destination file
|
|
-- shortly before, it's acceptable to run the callback anyway, as that's
|
|
-- nearly indistinguishable from the above case.
|
|
--
|
|
-- So, it suffices to check if the destination file's current
|
|
-- content is known, and immediately run the callback.
|
|
checkExportContent :: RawFilePath -> ExportLocation -> [ContentIdentifier] -> Annex a -> (CheckResult -> Annex a) -> Annex a
|
|
checkExportContent dir loc knowncids unsafe callback =
|
|
tryWhenExists (liftIO $ R.getFileStatus dest) >>= \case
|
|
Just destst
|
|
| not (isRegularFile destst) -> unsafe
|
|
| otherwise -> catchDefaultIO Nothing (liftIO $ mkContentIdentifier dest destst) >>= \case
|
|
Just destcid
|
|
| destcid `elem` knowncids -> callback KnownContentIdentifier
|
|
-- dest exists with other content
|
|
| otherwise -> unsafe
|
|
-- should never happen
|
|
Nothing -> unsafe
|
|
-- dest does not exist
|
|
Nothing -> callback DoesNotExist
|
|
where
|
|
dest = exportPath dir loc
|