avoid using openFile when withFile can be used

Potentially fixes some FD leak if an action on an opened file handle fails
for some reason. There have been some hard to reproduce reports of
git-annex leaking FDs, and this may solve them.

Annex/Content/Direct.hs

@@ -52,8 +52,7 @@ associatedFiles key = do
 associatedFilesRelative :: Key -> Annex [FilePath] 
 associatedFilesRelative key = do
 	mapping <- calcRepo $ gitAnnexMapping key
-	liftIO $ catchDefaultIO [] $ do
+	liftIO $ catchDefaultIO [] $ withFile mapping ReadMode $ \h -> do
-		h <- openFile mapping ReadMode
 		fileEncoding h
 		lines <$> hGetContents h
 

Annex/Link.hs

@@ -51,19 +51,15 @@ getAnnexLinkTarget file = ifM (coreSymlinks <$> Annex.getGitConfig)
 				| otherwise -> return Nothing
 			Nothing -> fallback
 
-	probefilecontent f = do
+	probefilecontent f = withFile f ReadMode $ \h -> do
-		h <- openFile f ReadMode
 		fileEncoding h
 		-- The first 8k is more than enough to read; link
 		-- files are small.
 		s <- take 8192 <$> hGetContents h
 		-- If we got the full 8k, the file is too large
 		if length s == 8192
-			then do
+			then return ""
-				hClose h
+			else 
-				return ""
-			else do
-				hClose h
 				-- If there are any NUL or newline
 				-- characters, or whitespace, we
 				-- certianly don't have a link to a

Command/Fsck.hs

@@ -478,10 +478,9 @@ recordStartTime = do
 	createAnnexDirectory $ parentDir f
 	liftIO $ do
 		nukeFile f
-		h <- openFile f WriteMode
+		withFile f WriteMode $ \h -> do
-		t <- modificationTime <$> getFileStatus f
+			t <- modificationTime <$> getFileStatus f
-		hPutStr h $ showTime $ realToFrac t
+			hPutStr h $ showTime $ realToFrac t
-		hClose h
   where
 	showTime :: POSIXTime -> String
 	showTime = show

Logs/Transfer.hs

@@ -340,11 +340,8 @@ parseTransferFile file
 	bits = splitDirectories file
 
 writeTransferInfoFile :: TransferInfo -> FilePath -> IO ()
-writeTransferInfoFile info tfile = do
+writeTransferInfoFile info tfile = writeFileAnyEncoding tfile $
-	h <- openFile tfile WriteMode
+	writeTransferInfo info
-	fileEncoding h
-	hPutStr h $ writeTransferInfo info
-	hClose h
 
 {- File format is a header line containing the startedTime and any
  - bytesComplete value. Followed by a newline and the associatedFile.
@@ -365,10 +362,8 @@ writeTransferInfo info = unlines
 	]
 
 readTransferInfoFile :: Maybe PID -> FilePath -> IO (Maybe TransferInfo)
-readTransferInfoFile mpid tfile = catchDefaultIO Nothing $ do
+readTransferInfoFile mpid tfile = catchDefaultIO Nothing $
-	h <- openFile tfile ReadMode
+	readTransferInfo mpid <$> readFileStrictAnyEncoding tfile
-	fileEncoding h
-	hClose h `after` (readTransferInfo mpid <$> hGetContentsStrict h)
 
 readTransferInfo :: Maybe PID -> String -> Maybe TransferInfo
 readTransferInfo mpid s = TransferInfo

Remote/Bup.hs

@@ -145,9 +145,8 @@ storeEncrypted r buprepo (cipher, enck) k _p =
 retrieve :: BupRepo -> Key -> AssociatedFile -> FilePath -> MeterUpdate -> Annex Bool
 retrieve buprepo k _f d _p = do
 	let params = bupParams "join" buprepo [Param $ bupRef k]
-	liftIO $ catchBoolIO $ do
+	liftIO $ catchBoolIO $ withFIle d WriteMode $
-		tofile <- openFile d WriteMode
+		pipeBup params Nothing . Just
-		pipeBup params Nothing (Just tofile)
 
 retrieveCheap :: BupRepo -> Key -> FilePath -> Annex Bool
 retrieveCheap _ _ _ = return False

Utility/FileMode.hs

@@ -133,10 +133,8 @@ setSticky f = modifyFileMode f $ addModes [stickyMode]
  - as writeFile.
  -}
 writeFileProtected :: FilePath -> String -> IO ()
-writeFileProtected file content = do
+writeFileProtected file content = withFile file WriteMode $ \h -> do
-	h <- openFile file WriteMode
 	void $ tryIO $
 		modifyFileMode file $
 			removeModes [groupReadMode, otherReadMode]
 	hPutStr h content
-	hClose h