git-annex/git-annex-shell.hs
Joey Hess 2bb6b02948 When not run in a git repository, git-annex can still display a usage message, and "git annex version" even works.
Things that sound simple, but are made hard by the Annex monad being built
with the assumption that there will always be a git repo.
2011-11-16 00:49:09 -04:00

112 lines
3 KiB
Haskell

{- git-annex-shell main program
-
- Copyright 2010 Joey Hess <joey@kitenet.net>
-
- Licensed under the GNU GPL version 3 or higher.
-}
import System.Environment
import System.Console.GetOpt
import Common.Annex
import qualified Git
import CmdLine
import Command
import Annex.UUID
import qualified Command.ConfigList
import qualified Command.InAnnex
import qualified Command.DropKey
import qualified Command.RecvKey
import qualified Command.SendKey
cmds_readonly :: [Command]
cmds_readonly = concat
[ Command.ConfigList.def
, Command.InAnnex.def
, Command.SendKey.def
]
cmds_notreadonly :: [Command]
cmds_notreadonly = concat
[ Command.RecvKey.def
, Command.DropKey.def
]
cmds :: [Command]
cmds = map adddirparam $ cmds_readonly ++ cmds_notreadonly
where
adddirparam c = c { cmdparams = "DIRECTORY " ++ cmdparams c }
options :: [OptDescr (Annex ())]
options = commonOptions ++
[ Option [] ["uuid"] (ReqArg checkuuid paramUUID) "repository uuid"
]
where
checkuuid expected = getUUID >>= check
where
check u | u == toUUID expected = return ()
check NoUUID = unexpected "uninitialized repository"
check u = unexpected $ "UUID " ++ fromUUID u
unexpected s = error $
"expected repository UUID " ++
expected ++ " but found " ++ s
header :: String
header = "Usage: git-annex-shell [-c] command [parameters ...] [option ..]"
main :: IO ()
main = main' =<< getArgs
main' :: [String] -> IO ()
main' [] = failure
-- skip leading -c options, passed by eg, ssh
main' ("-c":p) = main' p
-- a command can be either a builtin or something to pass to git-shell
main' c@(cmd:dir:params)
| cmd `elem` builtins = builtin cmd dir params
| otherwise = external c
main' c@(cmd:_)
-- Handle the case of being the user's login shell. It will be passed
-- a single string containing all the real parameters.
| "git-annex-shell " `isPrefixOf` cmd = main' $ drop 1 $ shellUnEscape cmd
| cmd `elem` builtins = failure
| otherwise = external c
builtins :: [String]
builtins = map cmdname cmds
builtin :: String -> String -> [String] -> IO ()
builtin cmd dir params = do
checkNotReadOnly cmd
dispatch (cmd : filterparams params) cmds options header $
Git.repoAbsPath dir >>= Git.repoFromAbsPath
external :: [String] -> IO ()
external params = do
checkNotLimited
unlessM (boolSystem "git-shell" $ map Param $ "-c":filterparams params) $
error "git-shell failed"
-- Drop all args after "--".
-- These tend to be passed by rsync and not useful.
filterparams :: [String] -> [String]
filterparams [] = []
filterparams ("--":_) = []
filterparams (a:as) = a:filterparams as
failure :: IO ()
failure = error $ "bad parameters\n\n" ++ usage header cmds options
checkNotLimited :: IO ()
checkNotLimited = checkEnv "GIT_ANNEX_SHELL_LIMITED"
checkNotReadOnly :: String -> IO ()
checkNotReadOnly cmd
| cmd `elem` map cmdname cmds_readonly = return ()
| otherwise = checkEnv "GIT_ANNEX_SHELL_READONLY"
checkEnv :: String -> IO ()
checkEnv var =
whenM (not . null <$> catchDefaultIO (getEnv var) "") $
error $ "Action blocked by " ++ var