git-annex/Git/Config.hs
2012-03-16 01:59:07 -04:00

72 lines
2.3 KiB
Haskell

{- git repository configuration handling
-
- Copyright 2010,2011 Joey Hess <joey@kitenet.net>
-
- Licensed under the GNU GPL version 3 or higher.
-}
module Git.Config where
import System.Posix.Directory
import Control.Exception (bracket_)
import qualified Data.Map as M
import Common
import Git
import Git.Types
import qualified Git.Construct
{- Returns a single git config setting, or a default value if not set. -}
get :: String -> String -> Repo -> String
get key defaultValue repo = M.findWithDefault defaultValue key (config repo)
{- Returns a single git config setting, if set. -}
getMaybe :: String -> Repo -> Maybe String
getMaybe key repo = M.lookup key (config repo)
{- Runs git config and populates a repo with its config. -}
read :: Repo -> IO Repo
read repo@(Repo { location = Dir d }) = bracketcd d $
{- Cannot use pipeRead because it relies on the config having
been already read. Instead, chdir to the repo. -}
pOpen ReadFromPipe "git" ["config", "--null", "--list"] $ hRead repo
where
bracketcd to a = bracketcd' to a =<< getCurrentDirectory
bracketcd' to a cwd
| dirContains to cwd = a
| otherwise = bracket_ (changeWorkingDirectory to) (changeWorkingDirectory cwd) a
read r = assertLocal r $
error $ "internal error; trying to read config of " ++ show r
{- Reads git config from a handle and populates a repo with it. -}
hRead :: Repo -> Handle -> IO Repo
hRead repo h = do
val <- hGetContentsStrict h
store val repo
{- Stores a git config into a repo, returning the new version of the repo.
- The git config may be multiple lines, or a single line. Config settings
- can be updated inrementally. -}
store :: String -> Repo -> IO Repo
store s repo = do
let c = parse s
let repo' = repo
{ config = (M.map Prelude.head c) `M.union` config repo
, fullconfig = M.unionWith (++) c (fullconfig repo)
}
rs <- Git.Construct.fromRemotes repo'
return $ repo' { remotes = rs }
{- Parses git config --list or git config --null --list output into a
- config map. -}
parse :: String -> M.Map String [String]
parse [] = M.empty
parse s
-- --list output will have an = in the first line
| all ('=' `elem`) (take 1 ls) = sep '=' ls
-- --null --list output separates keys from values with newlines
| otherwise = sep '\n' $ split "\0" s
where
ls = lines s
sep c = M.fromListWith (++) . map (\(k,v) -> (k, [v])) .
map (separate (== c))