git-annex/CmdLine.hs

70 lines
2.1 KiB
Haskell

{- git-annex command line parsing
-
- Copyright 2010 Joey Hess <joey@kitenet.net>
-
- Licensed under the GNU GPL version 3 or higher.
-}
module CmdLine (
dispatch,
parseCmd,
usage,
) where
import System.Console.GetOpt
import Control.Monad (when)
import Control.Monad.State (liftIO)
import qualified Annex
import qualified GitRepo as Git
import Types
import Command
import BackendList
import Core
import Upgrade
import Options
{- Runs the passed command line. -}
dispatch :: Git.Repo -> [String] -> [Command] -> [Option] -> String -> IO ()
dispatch gitrepo args cmds options header = do
state <- Annex.new gitrepo allBackends
(actions, state') <- Annex.run state $ parseCmd args header cmds options
tryRun state' $ [startup, upgrade] ++ actions
{- Parses command line, stores configure flags, and returns a
- list of actions to be run in the Annex monad. -}
parseCmd :: [String] -> String -> [Command] -> [Option] -> Annex [Annex Bool]
parseCmd argv header cmds options = do
(flags, params) <- liftIO $ getopt
when (null params) $ error $ "missing command" ++ usagemsg
case lookupCmd (head params) of
[] -> error $ "unknown command" ++ usagemsg
[command] -> do
_ <- sequence flags
prepCmd command (drop 1 params)
_ -> error "internal error: multiple matching commands"
where
getopt = case getOpt Permute options argv of
(flags, params, []) ->
return (flags, params)
(_, _, errs) ->
ioError (userError (concat errs ++ usagemsg))
lookupCmd cmd = filter (\c -> cmd == cmdname c) cmds
usagemsg = "\n\n" ++ usage header cmds options
{- Usage message with lists of commands and options. -}
usage :: String -> [Command] -> [Option] -> String
usage header cmds options =
usageInfo (header ++ "\n\nOptions:") options ++
"\nCommands:\n" ++ cmddescs
where
cmddescs = unlines $ map (indent . showcmd) cmds
showcmd c =
cmdname c ++
pad (longest cmdname + 1) (cmdname c) ++
cmdparams c ++
pad (longest cmdparams + 2) (cmdparams c) ++
cmddesc c
indent l = " " ++ l
pad n s = replicate (n - length s) ' '
longest f = foldl max 0 $ map (length . f) cmds