git-annex/Utility/Directory.hs
Joey Hess bb4f31a0ee Clean up handling of git directory and git worktree.
Baked into the code was an assumption that a repository's git directory
could be determined by adding ".git" to its work tree (or nothing for bare
repos). That fails when core.worktree, or GIT_DIR and GIT_WORK_TREE are
used to separate the two.

This was attacked at the type level, by storing the gitdir and worktree
separately, so Nothing for the worktree means a bare repo.

A complication arose because we don't learn where a repository is bare
until its configuration is read. So another Location type handles
repositories that have not had their config read yet. I am not entirely
happy with this being a Location type, rather than representing them
entirely separate from the Git type. The new code is not worse than the
old, but better types could enforce more safety.

Added support for core.worktree. Overriding it with -c isn't supported
because it's not really clear what to do if a git repo's config is read, is
not bare, and is then overridden to bare. What is the right git directory
in this case? I will worry about this if/when someone has a use case for
overriding core.worktree with -c. (See Git.Config.updateLocation)

Also removed and renamed some functions like gitDir and workTree that
misused git's terminology.

One minor regression is known: git annex add in a bare repository does not
print a nice error message, but runs git ls-files in a way that fails
earlier with a less nice error message. This is because before --work-tree
was always passed to git commands, even in a bare repo, while now it's not.
2012-05-18 17:03:12 -04:00

76 lines
2 KiB
Haskell

{- directory manipulation
-
- Copyright 2011 Joey Hess <joey@kitenet.net>
-
- Licensed under the GNU GPL version 3 or higher.
-}
module Utility.Directory where
import System.IO.Error
import System.Posix.Files
import System.Directory
import Control.Exception (throw)
import Control.Monad
import Control.Monad.IfElse
import System.FilePath
import Control.Applicative
import Control.Exception (bracket_)
import System.Posix.Directory
import Utility.SafeCommand
import Utility.TempFile
import Utility.Exception
import Utility.Monad
import Utility.Path
{- Lists the contents of a directory.
- Unlike getDirectoryContents, paths are not relative to the directory. -}
dirContents :: FilePath -> IO [FilePath]
dirContents d = map (d </>) . filter notcruft <$> getDirectoryContents d
where
notcruft "." = False
notcruft ".." = False
notcruft _ = True
{- Moves one filename to another.
- First tries a rename, but falls back to moving across devices if needed. -}
moveFile :: FilePath -> FilePath -> IO ()
moveFile src dest = tryIO (rename src dest) >>= onrename
where
onrename (Right _) = noop
onrename (Left e)
| isPermissionError e = rethrow
| isDoesNotExistError e = rethrow
| otherwise = do
-- copyFile is likely not as optimised as
-- the mv command, so we'll use the latter.
-- But, mv will move into a directory if
-- dest is one, which is not desired.
whenM (isdir dest) rethrow
viaTmp mv dest undefined
where
rethrow = throw e
mv tmp _ = do
ok <- boolSystem "mv" [Param "-f",
Param src, Param tmp]
unless ok $ do
-- delete any partial
_ <- tryIO $ removeFile tmp
rethrow
isdir f = do
r <- tryIO $ getFileStatus f
case r of
(Left _) -> return False
(Right s) -> return $ isDirectory s
{- Runs an action in another directory. -}
bracketCd :: FilePath -> IO a -> IO a
bracketCd dir a = go =<< getCurrentDirectory
where
go cwd
| dirContains dir cwd = a
| otherwise = bracket_
(changeWorkingDirectory dir)
(changeWorkingDirectory cwd)
a