prepare for new style chunking

Moved old legacy chunking code, and cleaned up the directory and webdav
remotes use of it, so when no chunking is configured, that code is not
used.

The config for new style chunking will be chunk=1M instead of chunksize=1M.

There should be no behavior changes from this commit.

This commit was sponsored by Andreas Laas.

4 files changed, 233 insertions, 196 deletions

diff --git a/Remote/Directory.hs b/Remote/Directory.hs
index afa2296ec..3158154e3 100644
--- a/Remote/Directory.hs
+++ b/Remote/Directory.hs
@@ -12,7 +12,6 @@ module Remote.Directory (remote) where
 import qualified Data.ByteString.Lazy as L
 import qualified Data.ByteString as S
 import qualified Data.Map as M
-import Data.Int
 
 import Common.Annex
 import Types.Remote
@@ -24,6 +23,7 @@ import Utility.FileMode
 import Remote.Helper.Special
 import Remote.Helper.Encryptable
 import Remote.Helper.Chunked
+import qualified Remote.Helper.Chunked.Legacy as Legacy
 import Crypto
 import Annex.Content
 import Annex.UUID
@@ -40,19 +40,19 @@ remote = RemoteType {
 gen :: Git.Repo -> UUID -> RemoteConfig -> RemoteGitConfig -> Annex (Maybe Remote)
 gen r u c gc = do
 	cst <- remoteCost gc cheapRemoteCost
-	let chunksize = chunkSize c
+	let chunkconfig = chunkConfig c
 	return $ Just $ encryptableRemote c
-		(storeEncrypted dir (getGpgEncParams (c,gc)) chunksize)
-		(retrieveEncrypted dir chunksize)
+		(storeEncrypted dir (getGpgEncParams (c,gc)) chunkconfig)
+		(retrieveEncrypted dir chunkconfig)
 		Remote {
 			uuid = u,
 			cost = cst,
 			name = Git.repoDescribe r,
-			storeKey = store dir chunksize,
-			retrieveKeyFile = retrieve dir chunksize,
-			retrieveKeyFileCheap = retrieveCheap dir chunksize,
+			storeKey = store dir chunkconfig,
+			retrieveKeyFile = retrieve dir chunkconfig,
+			retrieveKeyFileCheap = retrieveCheap dir chunkconfig,
 			removeKey = remove dir,
-			hasKey = checkPresent dir chunksize,
+			hasKey = checkPresent dir chunkconfig,
 			hasKeyCheap = True,
 			whereisKey = Nothing,
 			remoteFsck = Nothing,
@@ -97,77 +97,77 @@ storeDir d k = addTrailingPathSeparator $ d </> hashDirLower k </> keyFile k
 tmpDir :: FilePath -> Key -> FilePath
 tmpDir d k = addTrailingPathSeparator $ d </> "tmp" </> keyFile k
 
-withCheckedFiles :: (FilePath -> IO Bool) -> ChunkSize -> FilePath -> Key -> ([FilePath] -> IO Bool) -> IO Bool
+withCheckedFiles :: (FilePath -> IO Bool) -> ChunkConfig -> FilePath -> Key -> ([FilePath] -> IO Bool) -> IO Bool
 withCheckedFiles _ _ [] _ _ = return False
-withCheckedFiles check Nothing d k a = go $ locations d k
-  where
-	go [] = return False
-	go (f:fs) = ifM (check f) ( a [f] , go fs )
-withCheckedFiles check (Just _) d k a = go $ locations d k
+withCheckedFiles check (LegacyChunkSize _) d k a = go $ locations d k
   where
 	go [] = return False
 	go (f:fs) = do
-		let chunkcount = f ++ chunkCount
+		let chunkcount = f ++ Legacy.chunkCount
 		ifM (check chunkcount)
 			( do
-				chunks <- listChunks f <$> readFile chunkcount
+				chunks <- Legacy.listChunks f <$> readFile chunkcount
 				ifM (allM check chunks)
 					( a chunks , return False )
 			, do
-				chunks <- probeChunks f check
+				chunks <- Legacy.probeChunks f check
 				if null chunks
 					then go fs
 					else a chunks
 			)
+withCheckedFiles check _ d k a = go $ locations d k
+  where
+	go [] = return False
+	go (f:fs) = ifM (check f) ( a [f] , go fs )
 
-withStoredFiles :: ChunkSize -> FilePath -> Key -> ([FilePath] -> IO Bool) -> IO Bool
+withStoredFiles :: ChunkConfig -> FilePath -> Key -> ([FilePath] -> IO Bool) -> IO Bool
 withStoredFiles = withCheckedFiles doesFileExist
 
-store :: FilePath -> ChunkSize -> Key -> AssociatedFile -> MeterUpdate -> Annex Bool
-store d chunksize k _f p = sendAnnex k (void $ remove d k) $ \src ->
+store :: FilePath -> ChunkConfig -> Key -> AssociatedFile -> MeterUpdate -> Annex Bool
+store d chunkconfig k _f p = sendAnnex k (void $ remove d k) $ \src ->
 	metered (Just p) k $ \meterupdate -> 
-		storeHelper d chunksize k k $ \dests ->
-			case chunksize of
-				Nothing -> do
+		storeHelper d chunkconfig k k $ \dests ->
+			case chunkconfig of
+				LegacyChunkSize chunksize ->
+					storeLegacyChunked meterupdate chunksize dests
+						=<< L.readFile src
+				_ -> do
 					let dest = Prelude.head dests
 					meteredWriteFile meterupdate dest
 						=<< L.readFile src
 					return [dest]
-				Just _ ->
-					storeSplit meterupdate chunksize dests
-						=<< L.readFile src
 
-storeEncrypted :: FilePath -> [CommandParam] -> ChunkSize -> (Cipher, Key) -> Key -> MeterUpdate -> Annex Bool
-storeEncrypted d gpgOpts chunksize (cipher, enck) k p = sendAnnex k (void $ remove d enck) $ \src ->
+storeEncrypted :: FilePath -> [CommandParam] -> ChunkConfig -> (Cipher, Key) -> Key -> MeterUpdate -> Annex Bool
+storeEncrypted d gpgOpts chunkconfig (cipher, enck) k p = sendAnnex k (void $ remove d enck) $ \src ->
 	metered (Just p) k $ \meterupdate ->
-		storeHelper d chunksize enck k $ \dests ->
+		storeHelper d chunkconfig enck k $ \dests ->
 			encrypt gpgOpts cipher (feedFile src) $ readBytes $ \b ->
-				case chunksize of
-					Nothing -> do
+				case chunkconfig of
+					LegacyChunkSize chunksize ->
+						storeLegacyChunked meterupdate chunksize dests b
+					_ -> do
 						let dest = Prelude.head dests
 						meteredWriteFile meterupdate dest b
 						return [dest]
-					Just _ -> storeSplit meterupdate chunksize dests b
 
 {- Splits a ByteString into chunks and writes to dests, obeying configured
  - chunk size (not to be confused with the L.ByteString chunk size).
  - Note: Must always write at least one file, even for empty ByteString. -}
-storeSplit :: MeterUpdate -> ChunkSize -> [FilePath] -> L.ByteString -> IO [FilePath]
-storeSplit _ Nothing _ _ = error "bad storeSplit call"
-storeSplit _ _ [] _ = error "bad storeSplit call"
-storeSplit meterupdate (Just chunksize) alldests@(firstdest:_) b
+storeLegacyChunked :: MeterUpdate -> Legacy.ChunkSize -> [FilePath] -> L.ByteString -> IO [FilePath]
+storeLegacyChunked _ _ [] _ = error "bad storeLegacyChunked call"
+storeLegacyChunked meterupdate chunksize alldests@(firstdest:_) b
 	| L.null b = do
 		-- must always write at least one file, even for empty
 		L.writeFile firstdest b
 		return [firstdest]
-	| otherwise = storeSplit' meterupdate chunksize alldests (L.toChunks b) []
-storeSplit' :: MeterUpdate -> Int64 -> [FilePath] -> [S.ByteString] -> [FilePath] -> IO [FilePath]
-storeSplit' _ _ [] _ _ = error "ran out of dests"
-storeSplit' _ _  _ [] c = return $ reverse c
-storeSplit' meterupdate chunksize (d:dests) bs c = do
+	| otherwise = storeLegacyChunked' meterupdate chunksize alldests (L.toChunks b) []
+storeLegacyChunked' :: MeterUpdate -> Legacy.ChunkSize -> [FilePath] -> [S.ByteString] -> [FilePath] -> IO [FilePath]
+storeLegacyChunked' _ _ [] _ _ = error "ran out of dests"
+storeLegacyChunked' _ _  _ [] c = return $ reverse c
+storeLegacyChunked' meterupdate chunksize (d:dests) bs c = do
 	bs' <- withFile d WriteMode $
 		feed zeroBytesProcessed chunksize bs
-	storeSplit' meterupdate chunksize dests bs' (d:c)
+	storeLegacyChunked' meterupdate chunksize dests bs' (d:c)
   where
 	feed _ _ [] _ = return []
 	feed bytes sz (l:ls) h = do
@@ -181,19 +181,28 @@ storeSplit' meterupdate chunksize (d:dests) bs c = do
 				feed bytes' (sz - s) ls h
 			else return (l:ls)
 
-storeHelper :: FilePath -> ChunkSize -> Key -> Key -> ([FilePath] -> IO [FilePath]) -> Annex Bool
-storeHelper d chunksize key origkey storer = check <&&> go
+storeHelper :: FilePath -> ChunkConfig -> Key -> Key -> ([FilePath] -> IO [FilePath]) -> Annex Bool
+storeHelper d chunkconfig key origkey storer = check <&&> liftIO go
   where
 	tmpdir = tmpDir d key
 	destdir = storeDir d key
+
 	{- An encrypted key does not have a known size,
 	 - so check that the size of the original key is available as free
 	 - space. -}
 	check = do
 		liftIO $ createDirectoryIfMissing True tmpdir
 		checkDiskSpace (Just tmpdir) origkey 0
-	go = liftIO $ catchBoolIO $
-		storeChunks key tmpdir destdir chunksize storer recorder finalizer
+	
+	go = case chunkconfig of
+		NoChunks -> flip catchNonAsync (\e -> print e >> return False) $ do
+			let tmpf = tmpdir </> keyFile key
+			void $ storer [tmpf]
+			finalizer tmpdir destdir
+			return True
+		ChunkSize _ -> error "TODO: storeHelper with ChunkSize"
+		LegacyChunkSize _ -> Legacy.storeChunks key tmpdir destdir storer recorder finalizer
+
 	finalizer tmp dest = do
 		void $ tryIO $ allowWrite dest -- may already exist
 		void $ tryIO $ removeDirectoryRecursive dest -- or not exist
@@ -203,21 +212,22 @@ storeHelper d chunksize key origkey storer = check <&&> go
 		void $ tryIO $ do
 			mapM_ preventWrite =<< dirContents dest
 			preventWrite dest
+	
 	recorder f s = do
 		void $ tryIO $ allowWrite f
 		writeFile f s
 		void $ tryIO $ preventWrite f
 
-retrieve :: FilePath -> ChunkSize -> Key -> AssociatedFile -> FilePath -> MeterUpdate -> Annex Bool
-retrieve d chunksize k _ f p = metered (Just p) k $ \meterupdate ->
-	liftIO $ withStoredFiles chunksize d k $ \files ->
+retrieve :: FilePath -> ChunkConfig -> Key -> AssociatedFile -> FilePath -> MeterUpdate -> Annex Bool
+retrieve d chunkconfig k _ f p = metered (Just p) k $ \meterupdate ->
+	liftIO $ withStoredFiles chunkconfig d k $ \files ->
 		catchBoolIO $ do
-			meteredWriteFileChunks meterupdate f files L.readFile
+			Legacy.meteredWriteFileChunks meterupdate f files L.readFile
 			return True
 
-retrieveEncrypted :: FilePath -> ChunkSize -> (Cipher, Key) -> Key -> FilePath -> MeterUpdate -> Annex Bool
-retrieveEncrypted d chunksize (cipher, enck) k f p = metered (Just p) k $ \meterupdate ->
-	liftIO $ withStoredFiles chunksize d enck $ \files ->
+retrieveEncrypted :: FilePath -> ChunkConfig -> (Cipher, Key) -> Key -> FilePath -> MeterUpdate -> Annex Bool
+retrieveEncrypted d chunkconfig (cipher, enck) k f p = metered (Just p) k $ \meterupdate ->
+	liftIO $ withStoredFiles chunkconfig d enck $ \files ->
 		catchBoolIO $ do
 			decrypt cipher (feeder files) $
 				readBytes $ meteredWriteFile meterupdate f
@@ -225,10 +235,12 @@ retrieveEncrypted d chunksize (cipher, enck) k f p = metered (Just p) k $ \meter
   where
 	feeder files h = forM_ files $ L.hPut h <=< L.readFile
 
-retrieveCheap :: FilePath -> ChunkSize -> Key -> FilePath -> Annex Bool
-retrieveCheap _ (Just _) _ _ = return False -- no cheap retrieval for chunks
+retrieveCheap :: FilePath -> ChunkConfig -> Key -> FilePath -> Annex Bool
+-- no cheap retrieval for chunks
+retrieveCheap _ (ChunkSize _) _ _ = return False
+retrieveCheap _ (LegacyChunkSize _) _ _ = return False
 #ifndef mingw32_HOST_OS
-retrieveCheap d _ k f = liftIO $ withStoredFiles Nothing d k go
+retrieveCheap d ck k f = liftIO $ withStoredFiles ck d k go
   where
 	go [file] = catchBoolIO $ createSymbolicLink file f >> return True
 	go _files = return False
@@ -250,6 +262,6 @@ remove d k = liftIO $ do
   where
 	dir = storeDir d k
 
-checkPresent :: FilePath -> ChunkSize -> Key -> Annex (Either String Bool)
-checkPresent d chunksize k = liftIO $ catchMsgIO $ withStoredFiles chunksize d k $
+checkPresent :: FilePath -> ChunkConfig -> Key -> Annex (Either String Bool)
+checkPresent d chunkconfig k = liftIO $ catchMsgIO $ withStoredFiles chunkconfig d k $
 	const $ return True -- withStoredFiles checked that it exists
diff --git a/Remote/Helper/Chunked.hs b/Remote/Helper/Chunked.hs
index ad3b04d49..aafa6b700 100644
--- a/Remote/Helper/Chunked.hs
+++ b/Remote/Helper/Chunked.hs
@@ -1,144 +1,31 @@
 {- git-annex chunked remotes
  -
- - Copyright 2012 Joey Hess <joey@kitenet.net>
+ - Copyright 2012-2014 Joey Hess <joey@kitenet.net>
  -
  - Licensed under the GNU GPL version 3 or higher.
  -}
 
 module Remote.Helper.Chunked where
 
-import Common.Annex
 import Utility.DataUnits
 import Types.Remote
-import Utility.Metered
 
 import qualified Data.Map as M
-import qualified Data.ByteString.Lazy as L
 import Data.Int
-import qualified Control.Exception as E
 
-type ChunkSize = Maybe Int64
+data ChunkConfig
+	= NoChunks
+	| ChunkSize Int64
+	| LegacyChunkSize Int64
 
-{- Gets a remote's configured chunk size. -}
-chunkSize :: RemoteConfig -> ChunkSize
-chunkSize m =
+chunkConfig :: RemoteConfig -> ChunkConfig
+chunkConfig m =
 	case M.lookup "chunksize" m of
-		Nothing -> Nothing
-		Just v -> case readSize dataUnits v of
-			Nothing -> error "bad chunksize"
-			Just size
-				| size <= 0 -> error "bad chunksize"
-				| otherwise -> Just $ fromInteger size
-
-{- This is an extension that's added to the usual file (or whatever)
- - where the remote stores a key. -}
-type ChunkExt = String
-
-{- A record of the number of chunks used.
- -
- - While this can be guessed at based on the size of the key, encryption
- - makes that larger. Also, using this helps deal with changes to chunksize
- - over the life of a remote.
- -}
-chunkCount :: ChunkExt
-chunkCount = ".chunkcount"
-
-{- An infinite stream of extensions to use for chunks. -}
-chunkStream :: [ChunkExt]
-chunkStream = map (\n -> ".chunk" ++ show n) [1 :: Integer ..]
-
-{- Parses the String from the chunkCount file, and returns the files that
- - are used to store the chunks. -}
-listChunks :: FilePath -> String -> [FilePath]
-listChunks basedest chunkcount = take count $ map (basedest ++) chunkStream
-  where
-	count = fromMaybe 0 $ readish chunkcount
-
-{- For use when there is no chunkCount file; uses the action to find
- - chunks, and returns them, or Nothing if none found. Relies on
- - storeChunks's finalizer atomically moving the chunks into place once all
- - are written.
- -
- - This is only needed to work around a bug that caused the chunkCount file
- - not to be written.
- -}
-probeChunks :: FilePath -> (FilePath -> IO Bool) -> IO [FilePath]
-probeChunks basedest check = go [] $ map (basedest ++) chunkStream
+		Nothing -> case M.lookup "chunk" m of
+			Nothing -> NoChunks
+			Just v -> ChunkSize $ readsz v "chunk"
+		Just v -> LegacyChunkSize $ readsz v "chunksize"
   where
-	go l [] = return (reverse l)
-	go l (c:cs) = ifM (check c)
-		( go (c:l) cs
-		, go l []
-		)
-
-{- Given the base destination to use to store a value,
- - generates a stream of temporary destinations (just one when not chunking)
- - and passes it to an action, which should chunk and store the data,
- - and return the destinations it stored to, or [] on error. Then
- - calls the recorder to write the chunk count (if chunking). Finally, the
- - finalizer is called to rename the tmp into the dest 
- - (and do any other cleanup).
- -}
-storeChunks :: Key -> FilePath -> FilePath -> ChunkSize -> ([FilePath] -> IO [FilePath]) -> (FilePath -> String -> IO ()) -> (FilePath -> FilePath -> IO ()) -> IO Bool
-storeChunks key tmp dest chunksize storer recorder finalizer = either onerr return
-	=<< (E.try go :: IO (Either E.SomeException Bool))
-  where
-	go = do
-		stored <- storer tmpdests
-		when (isJust chunksize) $ do
-			let chunkcount = basef ++ chunkCount
-			recorder chunkcount (show $ length stored)
-		finalizer tmp dest
-		return (not $ null stored)
-	onerr e = do
-		print e
-		return False
-
-	basef = tmp ++ keyFile key
-	tmpdests
-		| isNothing chunksize = [basef]
-		| otherwise = map (basef ++ ) chunkStream
-
-{- Given a list of destinations to use, chunks the data according to the
- - ChunkSize, and runs the storer action to store each chunk. Returns
- - the destinations where data was stored, or [] on error.
- -
- - This buffers each chunk in memory.
- - More optimal versions of this can be written, that rely
- - on L.toChunks to split the lazy bytestring into chunks (typically
- - smaller than the ChunkSize), and eg, write those chunks to a Handle.
- - But this is the best that can be done with the storer interface that
- - writes a whole L.ByteString at a time.
- -}
-storeChunked :: ChunkSize -> [FilePath] -> (FilePath -> L.ByteString -> IO ()) -> L.ByteString -> IO [FilePath]
-storeChunked chunksize dests storer content = either onerr return
-	=<< (E.try (go chunksize dests) :: IO (Either E.SomeException [FilePath]))
-  where
-	go _ [] = return [] -- no dests!?
-	go Nothing (d:_) = do
-		storer d content
-		return [d]
-	go (Just sz) _
-		-- always write a chunk, even if the data is 0 bytes
-		| L.null content = go Nothing dests
-		| otherwise = storechunks sz [] dests content
-		
-	onerr e = do
-		print e
-		return []
-	
-	storechunks _ _ [] _ = return [] -- ran out of dests
-	storechunks sz useddests (d:ds) b
-		| L.null b = return $ reverse useddests
-		| otherwise = do
-			let (chunk, b') = L.splitAt sz b
-			storer d chunk
-			storechunks sz (d:useddests) ds b'
-
-{- Writes a series of chunks to a file. The feeder is called to get
- - each chunk. -}
-meteredWriteFileChunks :: MeterUpdate -> FilePath -> [v] -> (v -> IO L.ByteString) -> IO ()
-meteredWriteFileChunks meterupdate dest chunks feeder =
-	withBinaryFile dest WriteMode $ \h ->
-		forM_ chunks $
-			meteredWrite meterupdate h <=< feeder
+	readsz v f = case readSize dataUnits v of
+		Just size | size > 0 -> fromInteger size
+		_ -> error ("bad " ++ f)
diff --git a/Remote/Helper/Chunked/Legacy.hs b/Remote/Helper/Chunked/Legacy.hs
new file mode 100644
index 000000000..b35bc92a0
--- /dev/null
+++ b/Remote/Helper/Chunked/Legacy.hs
@@ -0,0 +1,127 @@
+{- legacy git-annex chunked remotes
+ -
+ - Copyright 2012 Joey Hess <joey@kitenet.net>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+module Remote.Helper.Chunked.Legacy where
+
+import Common.Annex
+import Utility.Metered
+
+import qualified Data.ByteString.Lazy as L
+import Data.Int
+import qualified Control.Exception as E
+
+type ChunkSize = Int64
+
+{- This is an extension that's added to the usual file (or whatever)
+ - where the remote stores a key. -}
+type ChunkExt = String
+
+{- A record of the number of chunks used.
+ -
+ - While this can be guessed at based on the size of the key, encryption
+ - makes that larger. Also, using this helps deal with changes to chunksize
+ - over the life of a remote.
+ -}
+chunkCount :: ChunkExt
+chunkCount = ".chunkcount"
+
+{- An infinite stream of extensions to use for chunks. -}
+chunkStream :: [ChunkExt]
+chunkStream = map (\n -> ".chunk" ++ show n) [1 :: Integer ..]
+
+{- Parses the String from the chunkCount file, and returns the files that
+ - are used to store the chunks. -}
+listChunks :: FilePath -> String -> [FilePath]
+listChunks basedest chunkcount = take count $ map (basedest ++) chunkStream
+  where
+	count = fromMaybe 0 $ readish chunkcount
+
+{- For use when there is no chunkCount file; uses the action to find
+ - chunks, and returns them, or Nothing if none found. Relies on
+ - storeChunks's finalizer atomically moving the chunks into place once all
+ - are written.
+ -
+ - This is only needed to work around a bug that caused the chunkCount file
+ - not to be written.
+ -}
+probeChunks :: FilePath -> (FilePath -> IO Bool) -> IO [FilePath]
+probeChunks basedest check = go [] $ map (basedest ++) chunkStream
+  where
+	go l [] = return (reverse l)
+	go l (c:cs) = ifM (check c)
+		( go (c:l) cs
+		, go l []
+		)
+
+{- Given the base destination to use to store a value,
+ - generates a stream of temporary destinations,
+ - and passes it to an action, which should chunk and store the data,
+ - and return the destinations it stored to, or [] on error. Then
+ - calls the recorder to write the chunk count. Finally, the
+ - finalizer is called to rename the tmp into the dest 
+ - (and do any other cleanup).
+ -}
+storeChunks :: Key -> FilePath -> FilePath -> ([FilePath] -> IO [FilePath]) -> (FilePath -> String -> IO ()) -> (FilePath -> FilePath -> IO ()) -> IO Bool
+storeChunks key tmp dest storer recorder finalizer = either onerr return
+	=<< (E.try go :: IO (Either E.SomeException Bool))
+  where
+	go = do
+		stored <- storer tmpdests
+		let chunkcount = basef ++ chunkCount
+		recorder chunkcount (show $ length stored)
+		finalizer tmp dest
+		return (not $ null stored)
+	onerr e = do
+		print e
+		return False
+
+	basef = tmp ++ keyFile key
+	tmpdests = map (basef ++ ) chunkStream
+
+{- Given a list of destinations to use, chunks the data according to the
+ - ChunkSize, and runs the storer action to store each chunk. Returns
+ - the destinations where data was stored, or [] on error.
+ -
+ - This buffers each chunk in memory.
+ - More optimal versions of this can be written, that rely
+ - on L.toChunks to split the lazy bytestring into chunks (typically
+ - smaller than the ChunkSize), and eg, write those chunks to a Handle.
+ - But this is the best that can be done with the storer interface that
+ - writes a whole L.ByteString at a time.
+ -}
+storeChunked :: ChunkSize -> [FilePath] -> (FilePath -> L.ByteString -> IO ()) -> L.ByteString -> IO [FilePath]
+storeChunked chunksize dests storer content = either onerr return
+	=<< (E.try (go (Just chunksize) dests) :: IO (Either E.SomeException [FilePath]))
+  where
+	go _ [] = return [] -- no dests!?
+	go Nothing (d:_) = do
+		storer d content
+		return [d]
+	go (Just sz) _
+		-- always write a chunk, even if the data is 0 bytes
+		| L.null content = go Nothing dests
+		| otherwise = storechunks sz [] dests content
+		
+	onerr e = do
+		print e
+		return []
+	
+	storechunks _ _ [] _ = return [] -- ran out of dests
+	storechunks sz useddests (d:ds) b
+		| L.null b = return $ reverse useddests
+		| otherwise = do
+			let (chunk, b') = L.splitAt sz b
+			storer d chunk
+			storechunks sz (d:useddests) ds b'
+
+{- Writes a series of chunks to a file. The feeder is called to get
+ - each chunk. -}
+meteredWriteFileChunks :: MeterUpdate -> FilePath -> [v] -> (v -> IO L.ByteString) -> IO ()
+meteredWriteFileChunks meterupdate dest chunks feeder =
+	withBinaryFile dest WriteMode $ \h ->
+		forM_ chunks $
+			meteredWrite meterupdate h <=< feeder
diff --git a/Remote/WebDAV.hs b/Remote/WebDAV.hs
index 91b83053c..3d618f79c 100644
--- a/Remote/WebDAV.hs
+++ b/Remote/WebDAV.hs
@@ -33,6 +33,7 @@ import Config.Cost
 import Remote.Helper.Special
 import Remote.Helper.Encryptable
 import Remote.Helper.Chunked
+import qualified Remote.Helper.Chunked.Legacy as Legacy
 import Crypto
 import Creds
 import Utility.Metered
@@ -111,13 +112,21 @@ storeEncrypted r (cipher, enck) k p = metered (Just p) k $ \meterupdate ->
 storeHelper :: Remote -> Key -> DavUrl -> DavUser -> DavPass -> L.ByteString -> IO Bool
 storeHelper r k baseurl user pass b = catchBoolIO $ do
 	mkdirRecursiveDAV tmpurl user pass
-	storeChunks k tmpurl keyurl chunksize storer recorder finalizer
+	case chunkconfig of
+		NoChunks -> flip catchNonAsync (\e -> print e >> return False) $ do
+			storehttp tmpurl b
+			finalizer tmpurl keyurl
+			return True
+		ChunkSize _ -> error "TODO: storeHelper with ChunkSize"
+		LegacyChunkSize chunksize -> do
+			let storer urls = Legacy.storeChunked chunksize urls storehttp b
+			let recorder url s = storehttp url (L8.fromString s)
+			Legacy.storeChunks k tmpurl keyurl storer recorder finalizer
+
   where
 	tmpurl = tmpLocation baseurl k
 	keyurl = davLocation baseurl k
-	chunksize = chunkSize $ config r
-	storer urls = storeChunked chunksize urls storehttp b
-	recorder url s = storehttp url (L8.fromString s)
+	chunkconfig = chunkConfig $ config r
 	finalizer srcurl desturl = do
 		void $ tryNonAsync (deleteDAV desturl user pass)
 		mkdirRecursiveDAV (urlParent desturl) user pass
@@ -131,7 +140,7 @@ retrieve :: Remote -> Key -> AssociatedFile -> FilePath -> MeterUpdate -> Annex
 retrieve r k _f d p = metered (Just p) k $ \meterupdate ->
 	davAction r False $ \(baseurl, user, pass) -> liftIO $ catchBoolIO $
 		withStoredFiles r k baseurl user pass onerr $ \urls -> do
-			meteredWriteFileChunks meterupdate d urls $ \url -> do
+			Legacy.meteredWriteFileChunks meterupdate d urls $ \url -> do
 				mb <- getDAV url user pass
 				case mb of
 					Nothing -> throwIO "download failed"
@@ -200,20 +209,22 @@ withStoredFiles
 	-> (DavUrl -> IO a)
 	-> ([DavUrl] -> IO a)
 	-> IO a
-withStoredFiles r k baseurl user pass onerr a
-	| isJust $ chunkSize $ config r = do
-		let chunkcount = keyurl ++ chunkCount
+withStoredFiles r k baseurl user pass onerr a = case chunkconfig of
+	NoChunks -> a [keyurl]
+	ChunkSize _ -> error "TODO: withStoredFiles with ChunkSize"
+	LegacyChunkSize _ -> do
+		let chunkcount = keyurl ++ Legacy.chunkCount
 		v <- getDAV chunkcount user pass
 		case v of
-			Just s -> a $ listChunks keyurl $ L8.toString s
+			Just s -> a $ Legacy.listChunks keyurl $ L8.toString s
 			Nothing -> do
-				chunks <- probeChunks keyurl $ \u -> (== Right True) <$> existsDAV u user pass
+				chunks <- Legacy.probeChunks keyurl $ \u -> (== Right True) <$> existsDAV u user pass
 				if null chunks
 					then onerr chunkcount
 					else a chunks
-	| otherwise = a [keyurl]
   where
 	keyurl = davLocation baseurl k ++ keyFile k
+	chunkconfig = chunkConfig $ config r
 
 davAction :: Remote -> a -> ((DavUrl, DavUser, DavPass) -> Annex a) -> Annex a
 davAction r unconfigured action = do