git-annex/Utility/CopyFile.hs
Joey Hess 6eb5c3f479 Do not preserve permissions and acls when copying files from one local git repository to another. Timestamps are still preserved as long as cp --preserve=timestamps is supported.
This avoids cp -a overriding the default mode acls that the user might have
set in a git repository.

With GNU cp, this behavior change should not be a breaking change, because
git-anex also uses rsync sometimes in the same situation, and has only ever
preserved timestamps when using rsync.

Systems without GNU cp will no longer use cp -a, but instead just cp.
So, timestamps will no longer be preserved. Preserving timestamps when
copying between repos is not guaranteed anyway.

Closes: #729757
2014-08-26 17:10:25 -07:00

56 lines
1.4 KiB
Haskell

{- file copying
-
- Copyright 2010-2014 Joey Hess <joey@kitenet.net>
-
- License: BSD-2-clause
-}
{-# LANGUAGE CPP #-}
module Utility.CopyFile (
copyFileExternal,
createLinkOrCopy,
CopyMetaData(..)
) where
import Common
import qualified Build.SysConfig as SysConfig
data CopyMetaData = CopyTimeStamps | CopyAllMetaData
deriving (Eq)
{- The cp command is used, because I hate reinventing the wheel,
- and because this allows easy access to features like cp --reflink. -}
copyFileExternal :: CopyMetaData -> FilePath -> FilePath -> IO Bool
copyFileExternal meta src dest = do
whenM (doesFileExist dest) $
removeFile dest
boolSystem "cp" $ params ++ [File src, File dest]
where
#ifndef __ANDROID__
params = map snd $ filter fst
[ (SysConfig.cp_reflink_auto, Param "--reflink=auto")
, (allmeta && SysConfig.cp_a, Param "-a")
, (allmeta && SysConfig.cp_p && not SysConfig.cp_a
, Param "-p")
, (not allmeta && SysConfig.cp_preserve_timestamps
, Param "--preserve=timestamps")
]
#else
params = []
#endif
allmeta = meta == CopyAllMetaData
{- Create a hard link if the filesystem allows it, and fall back to copying
- the file. -}
createLinkOrCopy :: FilePath -> FilePath -> IO Bool
#ifndef mingw32_HOST_OS
createLinkOrCopy src dest = go `catchIO` const fallback
where
go = do
createLink src dest
return True
fallback = copyFileExternal CopyAllMetaData src dest
#else
createLinkOrCopy = copyFileExternal CopyAllMetaData
#endif