git-annex/Utility/Path/Windows.hs
Joey Hess 6653e000f0 fix convertToWindowsNativeNameSpace bug
This fixes a test suite failure. The OsPath conversion made that be used
in more places, including addurl, which exposed an existing bug.
2025-02-11 20:37:40 -08:00

54 lines
1.7 KiB
Haskell

{- Windows paths
-
- Copyright 2022-2023 Joey Hess <id@joeyh.name>
-
- License: BSD-2-clause
-}
{-# LANGUAGE OverloadedStrings #-}
{-# OPTIONS_GHC -fno-warn-tabs #-}
module Utility.Path.Windows (
convertToWindowsNativeNamespace
) where
import Utility.Path
import Utility.OsPath
import qualified Utility.OsString as OS
import Utility.SystemDirectory
import Utility.FileSystemEncoding
import qualified Data.ByteString as B
import qualified System.FilePath.Windows as WinPath
{- Convert a filepath to use Windows's native namespace.
- This avoids filesystem length limits.
-
- This is similar to the way base converts filenames on windows,
- but as that is implemented in C (create_device_name) and not
- exported, it cannot be used here. Several edge cases are not handled,
- including network shares and dos short paths.
-}
convertToWindowsNativeNamespace :: RawFilePath -> IO RawFilePath
convertToWindowsNativeNamespace f
| win32_dev_namespace `B.isPrefixOf` f = return f
| win32_file_namespace `B.isPrefixOf` f = return f
| nt_device_namespace `B.isPrefixOf` f = return f
| otherwise = do
-- Make absolute because any '.' and '..' in the path
-- will not be resolved once it's converted.
cwd <- getCurrentDirectory
let p = simplifyPath (combine cwd (toOsPath f))
-- If the input path is absolute but does not include a drive,
-- add the drive from the cwd, because a path in the native
-- namespace must include a drive.
let p' = if OS.null (takeDrive p)
then joinDrive (takeDrive cwd) p
else p
-- Normalize slashes.
let p'' = encodeBS $ WinPath.normalise $ fromOsPath p'
return (win32_file_namespace <> p'')
where
win32_dev_namespace = "\\\\.\\"
win32_file_namespace = "\\\\?\\"
nt_device_namespace = "\\Device\\"