git-annex/Git/CheckAttr.hs
Joey Hess 5a275a3f5d Can now be built with older git versions (before 1.7.7); the resulting binary should only be used with old git.
Remove git old version check from configure, and use the git version
it was built against in the git check-attr code.
2011-12-22 15:01:13 -04:00

66 lines
1.8 KiB
Haskell

{- git check-attr interface
-
- Copyright 2010, 2011 Joey Hess <joey@kitenet.net>
-
- Licensed under the GNU GPL version 3 or higher.
-}
module Git.CheckAttr where
import System.Exit
import Common
import Git
import Git.Command
import qualified Git.Filename
import qualified Git.Version
{- Efficiently looks up a gitattributes value for each file in a list. -}
lookup :: String -> [FilePath] -> Repo -> IO [(FilePath, String)]
lookup attr files repo = do
cwd <- getCurrentDirectory
(_, fromh, toh) <- hPipeBoth "git" (toCommand params)
_ <- forkProcess $ do
hClose fromh
hPutStr toh $ join "\0" $ input cwd
hClose toh
exitSuccess
hClose toh
output cwd . lines <$> hGetContents fromh
where
params = gitCommandLine
[ Param "check-attr"
, Param attr
, Params "-z --stdin"
] repo
{- Before git 1.7.7, git check-attr worked best with
- absolute filenames; using them worked around some bugs
- with relative filenames.
-
- With newer git, git check-attr chokes on some absolute
- filenames, and the bugs that necessitated them were fixed,
- so use relative filenames. -}
oldgit = Git.Version.older "1.7.7"
input cwd
| oldgit = map (absPathFrom cwd) files
| otherwise = map (relPathDirToFile cwd . absPathFrom cwd) files
output cwd
| oldgit = map (torel cwd . topair)
| otherwise = map topair
topair l = (Git.Filename.decode file, value)
where
file = join sep $ beginning bits
value = end bits !! 0
bits = split sep l
sep = ": " ++ attr ++ ": "
torel cwd (file, value) = (relfile, value)
where
relfile
| startswith cwd' file = drop (length cwd') file
| otherwise = relPathDirToFile top' file
top = workTree repo
cwd' = cwd ++ "/"
top' = top ++ "/"