minor refactoring

Command/RecvKey.hs

@@ -20,8 +20,6 @@ import qualified Types.Key
 import qualified Types.Backend
 import qualified Backend
 
-import System.Console.GetOpt
-
 def :: [Command]
 def = [noCommit $ command "recvkey" paramKey seek
 	SectionPlumbing "runs rsync in server mode to receive content"]
@@ -44,8 +42,8 @@ start key = ifM (inAnnex key)
 	)
   where
 	go tmp = do
-		(opts,_,_) <- getOpt Permute rsyncSafeOptions <$>
-				maybe [] words <$> getField "RsyncOptions"
+		opts <- filterRsyncSafeOptions . maybe [] words
+			<$> getField "RsyncOptions"
 		ifM (liftIO $ rsyncServerReceive (map Param opts) tmp)
 			( ifM (isJust <$> Fields.getField Fields.direct)
 				( directcheck tmp

Command/SendKey.hs

@@ -16,8 +16,6 @@ import Logs.Transfer
 import qualified Fields
 import Utility.Metered
 
-import System.Console.GetOpt
-
 def :: [Command]
 def = [noCommit $ command "sendkey" paramKey seek
 	SectionPlumbing "runs rsync in server mode to send content"]
@@ -27,8 +25,8 @@ seek = [withKeys start]
 
 start :: Key -> CommandStart
 start key = do
-	(opts,_,_) <- getOpt Permute rsyncSafeOptions <$>
-			maybe [] words <$> getField "RsyncOptions"
+	opts <- filterRsyncSafeOptions . maybe [] words
+		<$> getField "RsyncOptions"
 	ifM (inAnnex key)
 		( fieldTransfer Upload key $ \_p ->
 			sendAnnex key rollback $ liftIO . rsyncServerSend (map Param opts)

Utility/Rsync.hs

@@ -12,6 +12,7 @@ import Utility.Metered
 
 import Data.Char
 import System.Console.GetOpt
+import Data.Tuple.Utils
 
 {- Generates parameters to make rsync use a specified command as its remote
  - shell. -}
@@ -130,13 +131,10 @@ parseRsyncProgress = go [] . reverse . progresschunks
 		(_, []) -> Nothing
 		(b, _) -> readish b
 
-{- Rsync options that are safe to pass to rsync in server mode, without
- - causing it to eg, expose files.
- -
- - Note: Ensure that when calling getopt, the first component of the
- - output is a subset of the input.
- -}
-rsyncSafeOptions :: [OptDescr String]
-rsyncSafeOptions = [ Option [] ["bwlimit"] (reqArgLong "bwlimit") "" ]
+{- Filters options to those that are safe to pass to rsync in server mode,
+ - without causing it to eg, expose files. -}
+filterRsyncSafeOptions :: [String] -> [String]
+filterRsyncSafeOptions = fst3 . getOpt Permute
+	[ Option [] ["bwlimit"] (reqArgLong "bwlimit") "" ]
   where
 	reqArgLong x = ReqArg (\v -> "--" ++ x ++ "=" ++ v) ""