refactor

Locations.hs

@@ -20,6 +20,7 @@ module Locations (
 	gitAnnexJournalDir,
 	gitAnnexJournalLock,
 	isLinkToAnnex,
+	annexHashes,
 	hashDirMixed,
 	hashDirLower,
 
@@ -58,10 +59,18 @@ annexDir = addTrailingPathSeparator "annex"
 objectDir :: FilePath
 objectDir = addTrailingPathSeparator $ annexDir </> "objects"
 
+{- Two different directory hashes may be used. The mixed case hash
+ - came first, and is fine, except for the problem of case-strict
+ - filesystems such as Linux VFAT (mounted with shortname=mixed),
+ - which do not allow using a directory "XX" when "xx" already exists.
+ - To support that, some repositories will use a lower case hash. -}
+annexHashes :: [Key -> FilePath]
+annexHashes = [hashDirMixed, hashDirLower]
+
 {- Annexed file's possible locations relative to the .git directory.
  - There are two different possibilities, using different hashes. -}
 annexLocations :: Key -> [FilePath]
-annexLocations key = map (annexLocation key) [hashDirMixed, hashDirLower]
+annexLocations key = map (annexLocation key) annexHashes
 annexLocation :: Key -> (Key -> FilePath) -> FilePath
 annexLocation key hasher = objectDir </> hasher key </> f </> f
 	where

Remote/Directory.hs

@@ -62,20 +62,10 @@ directorySetup u c = do
 	gitConfigSpecialRemote u c' "directory" dir
 	return $ M.delete "directory" c'
 
-{- Where to store a given Key in the Directory.
- -
- - There are two possible locations to try; this had to be done because
- - on Linux, vfat filesystem mounted with shortname=mixed have a
- - variant of case insensativity that causes miserable failure when
- - hashDirMixed produces eg, "xx" and "XX". The first directory to be
- - created wins the namespace, and the second one cannot then be created.
- - But unlike behavior with shortname=lower, "XX/foo" won't look in
- - "xx/foo".
- -}
+{- Locations to try to access a given Key in the Directory. -}
 locations :: FilePath -> Key -> [FilePath]
-locations d k = [using hashDirMixed, using hashDirLower]
+locations d k = map (\h -> d </> h k </> f </> f) annexHashes
 	where
-		using h = d </> h k </> f </> f
 		f = keyFile k
 
 withCheckedFile :: (FilePath -> IO Bool) -> FilePath -> Key -> (FilePath -> IO Bool) -> IO Bool