git-annex/Utility/CopyFile.hs
Joey Hess e36808e167 Pass -a to cp even when it supports --reflink=auto, to preserve permissions.
Amoung other things, this makes unlocking a WORM backed file and then
re-adding it without making any changes not add a new object, as the
timestamp is preserved.
2012-05-15 14:18:51 -04:00

25 lines
762 B
Haskell

{- git-annex file copying
-
- Copyright 2010,2012 Joey Hess <joey@kitenet.net>
-
- Licensed under the GNU GPL version 3 or higher.
-}
module Utility.CopyFile (copyFileExternal) where
import Common
import qualified Build.SysConfig as SysConfig
{- The cp command is used, because I hate reinventing the wheel,
- and because this allows easy access to features like cp --reflink. -}
copyFileExternal :: FilePath -> FilePath -> IO Bool
copyFileExternal src dest = do
whenM (doesFileExist dest) $
removeFile dest
boolSystem "cp" $ params ++ [File src, File dest]
where
params = map snd $ filter fst
[ (SysConfig.cp_reflink_auto, Param "--reflink=auto")
, (SysConfig.cp_a, Param "-a")
, (SysConfig.cp_p && not SysConfig.cp_a, Param "-p")
]