use lowercase hash by default; non-bare repos are a special case

Directory special remotes will now always store keys in the lowercase name,
which avoids the complication of catching failures to create the mixed case
name.

Git remotes using http will now try the lowercase name first.

Locations.hs

@@ -21,7 +21,6 @@ module Locations (
 	gitAnnexJournalDir,
 	gitAnnexJournalLock,
 	isLinkToAnnex,
-	annexHashes,
 	hashDirMixed,
 	hashDirLower,
 
@@ -80,8 +79,7 @@ gitAnnexLocation key r
 	| Git.repoIsLocalBare r =
 		{- Bare repositories default to hashDirLower for new
 		 - content, as it's more portable. -}
-		go (Git.workTree r) $
-			map (annexLocation key) [hashDirLower, hashDirMixed]
+		go (Git.workTree r) (annexLocations key)
 	| otherwise =
 		{- Non-bare repositories only use hashDirMixed, so
 		 - don't need to do any work to check if the file is
@@ -189,10 +187,10 @@ prop_idempotent_fileKey s = Just k == fileKey (keyFile k)
  - 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. -}
+ - To support that, most repositories use the lower case hash for new data. -}
 type Hasher = Key -> FilePath
 annexHashes :: [Hasher]
-annexHashes = [hashDirMixed, hashDirLower]
+annexHashes = [hashDirLower, hashDirMixed]
 
 hashDirMixed :: Hasher
 hashDirMixed k = addTrailingPathSeparator $ take 2 dir </> drop 2 dir

Remote/Directory.hs

@@ -64,7 +64,7 @@ directorySetup u c = do
 
 {- Locations to try to access a given Key in the Directory. -}
 locations :: FilePath -> Key -> [FilePath]
-locations d k = map (d </>) (keyLocations k)
+locations d k = map (d </>) (keyPaths k)
 
 withCheckedFile :: (FilePath -> IO Bool) -> FilePath -> Key -> (FilePath -> IO Bool) -> IO Bool
 withCheckedFile _ [] _ _ = return False
@@ -95,18 +95,16 @@ storeEncrypted d (cipher, enck) k = do
 			return True
 
 storeHelper :: FilePath -> Key -> (FilePath -> IO Bool) -> IO Bool
-storeHelper d key a = withCheckedFile check d key go
-	where
-		check dest = isJust <$> mkdir (parentDir dest)
-		mkdir = catchMaybeIO . createDirectoryIfMissing True
-		go dest = do
-			let dir = parentDir dest
-			allowWrite dir
-			ok <- a dest
-			when ok $ do
-				preventWrite dest
-				preventWrite dir
-			return ok
+storeHelper d key a = do
+	let dest = head $ locations d key
+	let dir = parentDir dest
+	createDirectoryIfMissing True dir
+	allowWrite dir
+	ok <- a dest
+	when ok $ do
+		preventWrite dest
+		preventWrite dir
+	return ok
 
 retrieve :: FilePath -> Key -> FilePath -> Annex Bool
 retrieve d k f = liftIO $ withStoredFile d k $ \file -> copyFileExternal file f