git-annex/Git/UpdateIndex.hs
Joey Hess c784ef4586 unify exception handling into Utility.Exception
Removed old extensible-exceptions, only needed for very old ghc.

Made webdav use Utility.Exception, to work after some changes in DAV's
exception handling.

Removed Annex.Exception. Mostly this was trivial, but note that
tryAnnex is replaced with tryNonAsync and catchAnnex replaced with
catchNonAsync. In theory that could be a behavior change, since the former
caught all exceptions, and the latter don't catch async exceptions.

However, in practice, nothing in the Annex monad uses async exceptions.
Grepping for throwTo and killThread only find stuff in the assistant,
which does not seem related.

Command.Add.undo is changed to accept a SomeException, and things
that use it for rollback now catch non-async exceptions, rather than
only IOExceptions.
2014-08-07 22:03:29 -04:00

110 lines
3.2 KiB
Haskell

{- git-update-index library
-
- Copyright 2011-2013 Joey Hess <joey@kitenet.net>
-
- Licensed under the GNU GPL version 3 or higher.
-}
{-# LANGUAGE BangPatterns, CPP #-}
module Git.UpdateIndex (
Streamer,
pureStreamer,
streamUpdateIndex,
streamUpdateIndex',
startUpdateIndex,
stopUpdateIndex,
lsTree,
lsSubTree,
updateIndexLine,
stageFile,
unstageFile,
stageSymlink
) where
import Common
import Git
import Git.Types
import Git.Command
import Git.FilePath
import Git.Sha
{- Streamers are passed a callback and should feed it lines in the form
- read by update-index, and generated by ls-tree. -}
type Streamer = (String -> IO ()) -> IO ()
{- A streamer with a precalculated value. -}
pureStreamer :: String -> Streamer
pureStreamer !s = \streamer -> streamer s
{- Streams content into update-index from a list of Streamers. -}
streamUpdateIndex :: Repo -> [Streamer] -> IO ()
streamUpdateIndex repo as = bracket (startUpdateIndex repo) stopUpdateIndex $
(\h -> forM_ as $ streamUpdateIndex' h)
data UpdateIndexHandle = UpdateIndexHandle ProcessHandle Handle
streamUpdateIndex' :: UpdateIndexHandle -> Streamer -> IO ()
streamUpdateIndex' (UpdateIndexHandle _ h) a = a $ \s -> do
hPutStr h s
hPutStr h "\0"
startUpdateIndex :: Repo -> IO UpdateIndexHandle
startUpdateIndex repo = do
(Just h, _, _, p) <- createProcess (gitCreateProcess params repo)
{ std_in = CreatePipe }
fileEncoding h
return $ UpdateIndexHandle p h
where
params = map Param ["update-index", "-z", "--index-info"]
stopUpdateIndex :: UpdateIndexHandle -> IO Bool
stopUpdateIndex (UpdateIndexHandle p h) = do
hClose h
checkSuccessProcess p
{- A streamer that adds the current tree for a ref. Useful for eg, copying
- and modifying branches. -}
lsTree :: Ref -> Repo -> Streamer
lsTree (Ref x) repo streamer = do
(s, cleanup) <- pipeNullSplit params repo
mapM_ streamer s
void $ cleanup
where
params = map Param ["ls-tree", "-z", "-r", "--full-tree", x]
lsSubTree :: Ref -> FilePath -> Repo -> Streamer
lsSubTree (Ref x) p repo streamer = do
(s, cleanup) <- pipeNullSplit params repo
mapM_ streamer s
void $ cleanup
where
params = map Param ["ls-tree", "-z", "-r", "--full-tree", x, p]
{- Generates a line suitable to be fed into update-index, to add
- a given file with a given sha. -}
updateIndexLine :: Sha -> BlobType -> TopFilePath -> String
updateIndexLine sha filetype file =
show filetype ++ " blob " ++ fromRef sha ++ "\t" ++ indexPath file
stageFile :: Sha -> BlobType -> FilePath -> Repo -> IO Streamer
stageFile sha filetype file repo = do
p <- toTopFilePath file repo
return $ pureStreamer $ updateIndexLine sha filetype p
{- A streamer that removes a file from the index. -}
unstageFile :: FilePath -> Repo -> IO Streamer
unstageFile file repo = do
p <- toTopFilePath file repo
return $ pureStreamer $ "0 " ++ fromRef nullSha ++ "\t" ++ indexPath p
{- A streamer that adds a symlink to the index. -}
stageSymlink :: FilePath -> Sha -> Repo -> IO Streamer
stageSymlink file sha repo = do
!line <- updateIndexLine
<$> pure sha
<*> pure SymlinkBlob
<*> toTopFilePath file repo
return $ pureStreamer line
indexPath :: TopFilePath -> InternalGitPath
indexPath = toInternalGitPath . getTopFilePath