use file-io for readFile/writeFile/appendFile on ByteStrings

These are all straightforward, and easy small performance wins.

Sponsored-by: Nicholas Golder-Manning

Upgrade/V1.hs

@@ -15,7 +15,6 @@ import Data.Default
 import Data.ByteString.Builder
 import qualified Data.ByteString as S
 import qualified Data.ByteString.Short as S (toShort, fromShort)
-import qualified Data.ByteString.Lazy as L
 import qualified System.FilePath.ByteString as P
 import System.PosixCompat.Files (isRegularFile)
 import Text.Read
@@ -35,6 +34,7 @@ import Utility.FileMode
 import Utility.Tmp
 import qualified Upgrade.V2
 import qualified Utility.RawFilePath as R
+import qualified Utility.FileIO as F
 
 -- v2 adds hashing of filenames of content and location log files.
 -- Key information is encoded in filenames differently, so
@@ -198,7 +198,7 @@ fileKey1 file = readKey1 $
 	replace "&a" "&" $ replace "&s" "%" $ replace "%" "/" file
 
 writeLog1 :: FilePath -> [LogLine] -> IO ()
-writeLog1 file ls = viaTmp (L.writeFile . fromRawFilePath . fromOsPath)
+writeLog1 file ls = viaTmp F.writeFile
 	(toOsPath (toRawFilePath file))
 	(toLazyByteString $ buildLog ls)
 

Upgrade/V5.hs

@@ -34,8 +34,7 @@ import Utility.InodeCache
 import Utility.DottedVersion
 import Annex.AdjustedBranch
 import qualified Utility.RawFilePath as R
-
-import qualified Data.ByteString as S
+import qualified Utility.FileIO as F
 
 upgrade :: Bool -> Annex UpgradeResult
 upgrade automatic = flip catchNonAsync onexception $ do
@@ -130,7 +129,7 @@ upgradeDirectWorkTree = do
 			Just k -> do
 				stagePointerFile f Nothing =<< hashPointerFile k
 				ifM (isJust <$> getAnnexLinkTarget f)
-					( writepointer (fromRawFilePath f) k
+					( writepointer f k
 					, fromdirect (fromRawFilePath f) k
 					)
 				Database.Keys.addAssociatedFile k
@@ -158,8 +157,8 @@ upgradeDirectWorkTree = do
 		)
 	
 	writepointer f k = liftIO $ do
-		removeWhenExistsWith R.removeLink (toRawFilePath f)
-		S.writeFile f (formatPointer k)
+		removeWhenExistsWith R.removeLink f
+		F.writeFile' (toOsPath f) (formatPointer k)
 
 {- Remove all direct mode bookkeeping files. -}
 removeDirectCruft :: Annex ()