f161b5eb59
When moving a file to the remote failed, and partially transferred content was left behind in the directory, re-running the same move would think it succeeded and delete the local copy. I reproduced data loss when moving files to a partition that was almost full. Interrupting a transfer could have similar results. Easily fixed by using a temp file which is then moved atomically into place once the transfer completes. I've audited other calls to copyFileExternal, and other special remote file transfer code; everything else seems to use temp files correctly (rsync, git), or otherwise use atomic transfers (bup, S3).
131 lines
3.7 KiB
Haskell
131 lines
3.7 KiB
Haskell
{- A "remote" that is just a filesystem directory.
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-
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- Copyright 2011 Joey Hess <joey@kitenet.net>
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-
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- Licensed under the GNU GPL version 3 or higher.
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-}
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module Remote.Directory (remote) where
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import qualified Data.ByteString.Lazy.Char8 as L
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import qualified Data.Map as M
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import Common.Annex
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import Utility.CopyFile
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import Types.Remote
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import qualified Git
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import Config
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import Utility.FileMode
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import Remote.Helper.Special
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import Remote.Helper.Encryptable
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import Crypto
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remote :: RemoteType
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remote = RemoteType {
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typename = "directory",
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enumerate = findSpecialRemotes "directory",
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generate = gen,
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setup = directorySetup
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}
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gen :: Git.Repo -> UUID -> Maybe RemoteConfig -> Annex Remote
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gen r u c = do
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dir <- getConfig r "directory" (error "missing directory")
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cst <- remoteCost r cheapRemoteCost
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return $ encryptableRemote c
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(storeEncrypted dir)
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(retrieveEncrypted dir)
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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 = store dir,
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retrieveKeyFile = retrieve dir,
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removeKey = remove dir,
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hasKey = checkPresent dir,
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hasKeyCheap = True,
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config = Nothing,
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repo = r,
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remotetype = remote
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}
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directorySetup :: UUID -> RemoteConfig -> Annex RemoteConfig
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directorySetup u c = do
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-- verify configuration is sane
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let dir = fromMaybe (error "Specify directory=") $
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M.lookup "directory" c
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liftIO $ doesDirectoryExist dir
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>>! error $ "Directory does not exist: " ++ dir
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c' <- encryptionSetup c
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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" dir
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return $ M.delete "directory" c'
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{- Locations to try to access a given Key in the Directory. -}
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locations :: FilePath -> Key -> [FilePath]
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locations d k = map (d </>) (keyPaths k)
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withCheckedFile :: (FilePath -> IO Bool) -> FilePath -> Key -> (FilePath -> IO Bool) -> IO Bool
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withCheckedFile _ [] _ _ = return False
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withCheckedFile check d k a = go $ locations d k
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where
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go [] = return False
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go (f:fs) = do
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use <- check f
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if use
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then a f
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else go fs
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withStoredFile :: FilePath -> Key -> (FilePath -> IO Bool) -> IO Bool
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withStoredFile = withCheckedFile doesFileExist
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store :: FilePath -> Key -> Annex Bool
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store d k = do
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src <- inRepo $ gitAnnexLocation k
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liftIO $ catchBoolIO $ storeHelper d k $ copyFileExternal src
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storeEncrypted :: FilePath -> (Cipher, Key) -> Key -> Annex Bool
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storeEncrypted d (cipher, enck) k = do
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src <- inRepo $ gitAnnexLocation k
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liftIO $ catchBoolIO $ storeHelper d enck $ encrypt src
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where
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encrypt src dest = do
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withEncryptedContent cipher (L.readFile src) $ L.writeFile dest
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return True
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storeHelper :: FilePath -> Key -> (FilePath -> IO Bool) -> IO Bool
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storeHelper d key a = do
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let dest = Prelude.head $ locations d key
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let tmpdest = dest ++ ".tmp"
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let dir = parentDir dest
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createDirectoryIfMissing True dir
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allowWrite dir
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ok <- a tmpdest
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when ok $ do
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renameFile tmpdest dest
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preventWrite dest
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preventWrite dir
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return ok
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retrieve :: FilePath -> Key -> FilePath -> Annex Bool
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retrieve d k f = liftIO $ withStoredFile d k $ \file -> copyFileExternal file f
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retrieveEncrypted :: FilePath -> (Cipher, Key) -> FilePath -> Annex Bool
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retrieveEncrypted d (cipher, enck) f =
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liftIO $ withStoredFile d enck $ \file -> catchBoolIO $ do
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withDecryptedContent cipher (L.readFile file) $ L.writeFile f
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return True
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remove :: FilePath -> Key -> Annex Bool
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remove d k = liftIO $ withStoredFile d k $ \file -> catchBoolIO $ do
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let dir = parentDir file
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allowWrite dir
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removeFile file
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removeDirectory dir
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return True
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checkPresent :: FilePath -> Key -> Annex (Either String Bool)
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checkPresent d k = liftIO $ catchMsgIO $ withStoredFile d k $
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const $ return True -- withStoredFile checked that it exists
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