git-annex/Git/Command.hs
2011-12-14 15:56:11 -04:00

82 lines
2.9 KiB
Haskell

{- running git commands
-
- Copyright 2010, 2011 Joey Hess <joey@kitenet.net>
-
- Licensed under the GNU GPL version 3 or higher.
-}
module Git.Command where
import qualified Data.ByteString.Lazy.Char8 as L
import Common
import Git
import Git.Types
{- Constructs a git command line operating on the specified repo. -}
gitCommandLine :: [CommandParam] -> Repo -> [CommandParam]
gitCommandLine params repo@(Repo { location = Dir _ } ) =
-- force use of specified repo via --git-dir and --work-tree
[ Param ("--git-dir=" ++ gitDir repo)
, Param ("--work-tree=" ++ workTree repo)
] ++ params
gitCommandLine _ repo = assertLocal repo $ error "internal"
{- Runs git in the specified repo. -}
runBool :: String -> [CommandParam] -> Repo -> IO Bool
runBool subcommand params repo = assertLocal repo $
boolSystem "git" $ gitCommandLine (Param subcommand : params) repo
{- Runs git in the specified repo, throwing an error if it fails. -}
run :: String -> [CommandParam] -> Repo -> IO ()
run subcommand params repo = assertLocal repo $
runBool subcommand params repo
>>! error $ "git " ++ show params ++ " failed"
{- Runs a git subcommand and returns its output, lazily.
-
- Note that this leaves the git process running, and so zombies will
- result unless reap is called.
-}
pipeRead :: [CommandParam] -> Repo -> IO L.ByteString
pipeRead params repo = assertLocal repo $ do
(_, h) <- hPipeFrom "git" $ toCommand $ gitCommandLine params repo
hSetBinaryMode h True
L.hGetContents h
{- Runs a git subcommand, feeding it input.
- You should call either getProcessStatus or forceSuccess on the PipeHandle. -}
pipeWrite :: [CommandParam] -> L.ByteString -> Repo -> IO PipeHandle
pipeWrite params s repo = assertLocal repo $ do
(p, h) <- hPipeTo "git" (toCommand $ gitCommandLine params repo)
L.hPut h s
hClose h
return p
{- Runs a git subcommand, feeding it input, and returning its output.
- You should call either getProcessStatus or forceSuccess on the PipeHandle. -}
pipeWriteRead :: [CommandParam] -> L.ByteString -> Repo -> IO (PipeHandle, L.ByteString)
pipeWriteRead params s repo = assertLocal repo $ do
(p, from, to) <- hPipeBoth "git" (toCommand $ gitCommandLine params repo)
hSetBinaryMode from True
L.hPut to s
hClose to
c <- L.hGetContents from
return (p, c)
{- Reads null terminated output of a git command (as enabled by the -z
- parameter), and splits it. -}
pipeNullSplit :: [CommandParam] -> Repo -> IO [String]
pipeNullSplit params repo = map L.unpack <$> pipeNullSplitB params repo
{- For when Strings are not needed. -}
pipeNullSplitB ::[CommandParam] -> Repo -> IO [L.ByteString]
pipeNullSplitB params repo = filter (not . L.null) . L.split '\0' <$>
pipeRead params repo
{- Reaps any zombie git processes. -}
reap :: IO ()
reap = do
-- throws an exception when there are no child processes
r <- catchDefaultIO (getAnyProcessStatus False True) Nothing
maybe (return ()) (const reap) r