OsPath conversion

Decent win in exportDirectories, since it operates on ShortByteString
end to end now without needing conversion. That made it worth
implementing an OsPath specific code path there.

And ExportLocation already being a ShortByteString is an good example of why
it's a good thing that OsPath uses that!

Sponsored-by: k0ld on Patreon

Types/Export.hs

@@ -1,11 +1,12 @@
 {- git-annex export types
  -
- - Copyright 2017-2021 Joey Hess <id@joeyh.name>
+ - Copyright 2017-2025 Joey Hess <id@joeyh.name>
  -
  - Licensed under the GNU AGPL version 3 or higher.
  -}
 
 {-# LANGUAGE DeriveGeneric #-}
+{-# LANGUAGE CPP #-}
 
 module Types.Export (
 	ExportLocation,
@@ -19,48 +20,63 @@ module Types.Export (
 
 import Git.FilePath
 import Utility.Split
-import Utility.FileSystemEncoding
+import Utility.OsPath
 
-import qualified Data.ByteString.Short as S
-import qualified System.FilePath.Posix as Posix
 import GHC.Generics
 import Control.DeepSeq
+#ifdef WITH_OSPATH
+import qualified System.OsPath.Posix as Posix
+import System.OsString.Internal.Types
+#else
+import qualified System.FilePath.Posix as Posix
+import Utility.FileSystemEncoding
+#endif
 
 -- A location such as a path on a remote, that a key can be exported to.
 -- The path is relative to the top of the remote, and uses unix-style
 -- path separators.
 --
--- This uses a ShortByteString to avoid problems with ByteString getting
+-- This must be a ShortByteString (which OsPath is) in order to to avoid
--- PINNED in memory which caused memory fragmentation and excessive memory
+-- problems with ByteString getting PINNED in memory which caused memory
--- use.
+-- fragmentation and excessive memory use.
-newtype ExportLocation = ExportLocation S.ShortByteString
+newtype ExportLocation = ExportLocation OsPath
 	deriving (Show, Eq, Generic, Ord)
 
 instance NFData ExportLocation
 
-mkExportLocation :: RawFilePath -> ExportLocation
+mkExportLocation :: OsPath -> ExportLocation
-mkExportLocation = ExportLocation . S.toShort . toInternalGitPath
+mkExportLocation = ExportLocation . toInternalGitPath
 
-fromExportLocation :: ExportLocation -> RawFilePath
+fromExportLocation :: ExportLocation -> OsPath
-fromExportLocation (ExportLocation f) = S.fromShort f
+fromExportLocation (ExportLocation f) = f
 
-newtype ExportDirectory = ExportDirectory RawFilePath
+newtype ExportDirectory = ExportDirectory OsPath
 	deriving (Show, Eq)
 
-mkExportDirectory :: RawFilePath -> ExportDirectory
+mkExportDirectory :: OsPath -> ExportDirectory
 mkExportDirectory = ExportDirectory . toInternalGitPath
 
-fromExportDirectory :: ExportDirectory -> RawFilePath
+fromExportDirectory :: ExportDirectory -> OsPath
 fromExportDirectory (ExportDirectory f) = f
 
 -- | All subdirectories down to the ExportLocation, with the deepest ones
 -- last. Does not include the top of the export.
 exportDirectories :: ExportLocation -> [ExportDirectory]
 exportDirectories (ExportLocation f) =
-	map (ExportDirectory . encodeBS . Posix.joinPath . reverse) (subs [] dirs)
+	map (ExportDirectory . fromposixpath . Posix.joinPath . reverse)
+		(subs [] dirs)
   where
 	subs _ [] = []
 	subs ps (d:ds) = (d:ps) : subs (d:ps) ds
 
+#ifdef WITH_OSPATH
 	dirs = map Posix.dropTrailingPathSeparator $
-		dropFromEnd 1 $ Posix.splitPath $ decodeBS $ S.fromShort f
+		dropFromEnd 1 $ Posix.splitPath $ PosixString $ fromOsPath f
+
+	fromposixpath = toOsPath . getPosixString
+#else
+	dirs = map Posix.dropTrailingPathSeparator $
+		dropFromEnd 1 $ Posix.splitPath $ fromOsPath f
+
+	fromposixpath = encodeBS
+#endif