git-annex/Git/Config.hs
Joey Hess 2670890b17
convert to withCreateProcess for async exception safety
This handles all createProcessSuccess callers, and aside from process
pools, the complete conversion of all process running to async exception
safety should be complete now.

Also, was able to remove from Utility.Process the old API that I now
know was not a good idea. And proof it was bad: The code size went *down*,
despite there being a fair bit of boilerplate for some future API to
reduce.
2020-06-04 15:45:52 -04:00

259 lines
7.8 KiB
Haskell

{- git repository configuration handling
-
- Copyright 2010-2020 Joey Hess <id@joeyh.name>
-
- Licensed under the GNU AGPL version 3 or higher.
-}
{-# LANGUAGE OverloadedStrings #-}
module Git.Config where
import qualified Data.Map as M
import qualified Data.ByteString as S
import qualified Data.ByteString.Char8 as S8
import Data.Char
import qualified System.FilePath.ByteString as P
import Control.Concurrent.Async
import Common
import Git
import Git.Types
import qualified Git.Command
import qualified Git.Construct
import Utility.UserInfo
{- Returns a single git config setting, or a fallback value if not set. -}
get :: ConfigKey -> ConfigValue -> Repo -> ConfigValue
get key fallback repo = M.findWithDefault fallback key (config repo)
{- Returns a list of values. -}
getList :: ConfigKey -> Repo -> [ConfigValue]
getList key repo = M.findWithDefault [] key (fullconfig repo)
{- Returns a single git config setting, if set. -}
getMaybe :: ConfigKey -> Repo -> Maybe ConfigValue
getMaybe key repo = M.lookup key (config repo)
{- Runs git config and populates a repo with its config.
- Avoids re-reading config when run repeatedly. -}
read :: Repo -> IO Repo
read repo@(Repo { config = c })
| c == M.empty = read' repo
| otherwise = return repo
{- Reads config even if it was read before. -}
reRead :: Repo -> IO Repo
reRead r = read' $ r
{ config = M.empty
, fullconfig = M.empty
}
{- Cannot use pipeRead because it relies on the config having been already
- read. Instead, chdir to the repo and run git config.
-}
read' :: Repo -> IO Repo
read' repo = go repo
where
go Repo { location = Local { gitdir = d } } = git_config d
go Repo { location = LocalUnknown d } = git_config d
go _ = assertLocal repo $ error "internal"
git_config d = withCreateProcess p (git_config' p)
where
params = ["config", "--null", "--list"]
p = (proc "git" params)
{ cwd = Just (fromRawFilePath d)
, env = gitEnv repo
, std_out = CreatePipe
}
git_config' p _ (Just hout) _ pid =
forceSuccessProcess p pid
`after`
hRead repo ConfigNullList hout
git_config' _ _ _ _ _ = error "internal"
{- Gets the global git config, returning a dummy Repo containing it. -}
global :: IO (Maybe Repo)
global = do
home <- myHomeDir
ifM (doesFileExist $ home </> ".gitconfig")
( Just <$> withCreateProcess p go
, return Nothing
)
where
params = ["config", "--null", "--list", "--global"]
p = (proc "git" params)
{ std_out = CreatePipe }
go _ (Just hout) _ pid =
forceSuccessProcess p pid
`after`
hRead (Git.Construct.fromUnknown) ConfigNullList hout
go _ _ _ _ = error "internal"
{- Reads git config from a handle and populates a repo with it. -}
hRead :: Repo -> ConfigStyle -> Handle -> IO Repo
hRead repo st h = do
val <- S.hGetContents h
store val st 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 incrementally.
-}
store :: S.ByteString -> ConfigStyle -> Repo -> IO Repo
store s st repo = do
let c = parse s st
updateLocation $ repo
{ config = (M.map Prelude.head c) `M.union` config repo
, fullconfig = M.unionWith (++) c (fullconfig repo)
}
{- Stores a single config setting in a Repo, returning the new version of
- the Repo. Config settings can be updated incrementally. -}
store' :: ConfigKey -> ConfigValue -> Repo -> Repo
store' k v repo = repo
{ config = M.singleton k v `M.union` config repo
, fullconfig = M.unionWith (++) (M.singleton k [v]) (fullconfig repo)
}
{- Updates the location of a repo, based on its configuration.
-
- Git.Construct makes LocalUknown repos, of which only a directory is
- known. Once the config is read, this can be fixed up to a Local repo,
- based on the core.bare and core.worktree settings.
-}
updateLocation :: Repo -> IO Repo
updateLocation r@(Repo { location = LocalUnknown d })
| isBare r = ifM (doesDirectoryExist (fromRawFilePath dotgit))
( updateLocation' r $ Local dotgit Nothing
, updateLocation' r $ Local d Nothing
)
| otherwise = updateLocation' r $ Local dotgit (Just d)
where
dotgit = d P.</> ".git"
updateLocation r@(Repo { location = l@(Local {}) }) = updateLocation' r l
updateLocation r = return r
updateLocation' :: Repo -> RepoLocation -> IO Repo
updateLocation' r l = do
l' <- case getMaybe "core.worktree" r of
Nothing -> return l
Just (ConfigValue d) -> do
{- core.worktree is relative to the gitdir -}
top <- absPath $ fromRawFilePath (gitdir l)
let p = absPathFrom top (fromRawFilePath d)
return $ l { worktree = Just (toRawFilePath p) }
Just NoConfigValue -> return l
return $ r { location = l' }
data ConfigStyle = ConfigList | ConfigNullList
{- Parses git config --list or git config --null --list output into a
- config map. -}
parse :: S.ByteString -> ConfigStyle -> M.Map ConfigKey [ConfigValue]
parse s st
| S.null s = M.empty
| otherwise = case st of
ConfigList -> sep eq $ S.split nl s
ConfigNullList -> sep nl $ S.split 0 s
where
nl = fromIntegral (ord '\n')
eq = fromIntegral (ord '=')
sep c = M.fromListWith (++)
. map (\(k,v) -> (ConfigKey k, [mkval v]))
. map (S.break (== c))
mkval v
| S.null v = NoConfigValue
| otherwise = ConfigValue (S.drop 1 v)
{- Checks if a string from git config is a true/false value. -}
isTrueFalse :: String -> Maybe Bool
isTrueFalse = isTrueFalse' . ConfigValue . encodeBS'
isTrueFalse' :: ConfigValue -> Maybe Bool
isTrueFalse' (ConfigValue s)
| s' == "yes" = Just True
| s' == "on" = Just True
| s' == "true" = Just True
| s' == "1" = Just True
| s' == "no" = Just False
| s' == "off" = Just False
| s' == "false" = Just False
| s' == "0" = Just False
| s' == "" = Just False
| otherwise = Nothing
where
s' = S8.map toLower s
isTrueFalse' NoConfigValue = Just True
boolConfig :: Bool -> String
boolConfig True = "true"
boolConfig False = "false"
boolConfig' :: Bool -> S.ByteString
boolConfig' True = "true"
boolConfig' False = "false"
isBare :: Repo -> Bool
isBare r = fromMaybe False $ isTrueFalse' =<< getMaybe coreBare r
coreBare :: ConfigKey
coreBare = "core.bare"
{- Runs a command to get the configuration of a repo,
- and returns a repo populated with the configuration, as well as the raw
- output and any standard output of the command. -}
fromPipe :: Repo -> String -> [CommandParam] -> ConfigStyle -> IO (Either SomeException (Repo, S.ByteString, S.ByteString))
fromPipe r cmd params st = try $ withCreateProcess p go
where
p = (proc cmd $ toCommand params)
{ std_out = CreatePipe
, std_err = CreatePipe
}
go _ (Just hout) (Just herr) pid = do
(val, err) <- concurrently
(S.hGetContents hout)
(S.hGetContents herr)
forceSuccessProcess p pid
r' <- store val st r
return (r', val, err)
go _ _ _ _ = error "internal"
{- Reads git config from a specified file and returns the repo populated
- with the configuration. -}
fromFile :: Repo -> FilePath -> IO (Either SomeException (Repo, S.ByteString, S.ByteString))
fromFile r f = fromPipe r "git"
[ Param "config"
, Param "--file"
, File f
, Param "--list"
] ConfigList
{- Changes a git config setting in the specified config file.
- (Creates the file if it does not already exist.) -}
changeFile :: FilePath -> ConfigKey -> S.ByteString -> IO Bool
changeFile f (ConfigKey k) v = boolSystem "git"
[ Param "config"
, Param "--file"
, File f
, Param (decodeBS' k)
, Param (decodeBS' v)
]
{- Unsets a git config setting, in both the git repo,
- and the cached config in the Repo.
-
- If unsetting the config fails, including in a read-only repo, or
- when the config is not set, returns Nothing.
-}
unset :: ConfigKey -> Repo -> IO (Maybe Repo)
unset ck@(ConfigKey k) r = ifM (Git.Command.runBool ps r)
( return $ Just $ r { config = M.delete ck (config r) }
, return Nothing
)
where
ps = [Param "config", Param "--unset-all", Param (decodeBS' k)]