git-annex/Annex/GitOverlay.hs
Joey Hess cd544e548b
filter out control characters in error messages
giveup changed to filter out control characters. (It is too low level to
make it use StringContainingQuotedPath.)

error still does not, but it should only be used for internal errors,
where the message is not attacker-controlled.

Changed a lot of existing error to giveup when it is not strictly an
internal error.

Of course, other exceptions can still be thrown, either by code in
git-annex, or a library, that include some attacker-controlled value.
This does not guard against those.

Sponsored-by: Noam Kremen on Patreon
2023-04-10 13:50:51 -04:00

124 lines
3.9 KiB
Haskell

{- Temporarily changing how git-annex runs git commands.
-
- Copyright 2014-2020 Joey Hess <id@joeyh.name>
-
- Licensed under the GNU AGPL version 3 or higher.
-}
module Annex.GitOverlay (
module Annex.GitOverlay,
AltIndexFile(..),
) where
import qualified Control.Exception as E
import Annex.Common
import Types.IndexFiles
import Git
import Git.Types
import Git.Index
import Git.Env
import qualified Annex
import qualified Annex.Queue
import Config.Smudge
{- Runs an action using a different git index file. -}
withIndexFile :: AltIndexFile -> (FilePath -> Annex a) -> Annex a
withIndexFile i = withAltRepo usecachedgitenv restoregitenv
where
-- This is an optimisation. Since withIndexFile is run repeatedly,
-- typically with the same file, and addGitEnv uses the slow
-- getEnvironment when gitEnv is Nothing, and has to do a
-- nontrivial amount of work, we cache the modified environment
-- the first time, and reuse it in subsequent calls for the same
-- index file.
--
-- (This could be done at another level; eg when creating the
-- Git object in the first place, but it's more efficient to let
-- the environment be inherited in all calls to git where it
-- does not need to be modified.)
--
-- Also, the use of AltIndexFile avoids needing to construct
-- the FilePath each time, which saves enough time to be worth the
-- added complication.
usecachedgitenv g = case gitEnv g of
Nothing -> Annex.withState $ \s -> case Annex.cachedgitenv s of
Just (cachedi, cachedf, cachede) | i == cachedi ->
return (s, (g { gitEnv = Just cachede }, cachedf))
_ -> do
r@(g', f) <- addindex g
let cache = (,,)
<$> Just i
<*> Just f
<*> gitEnv g'
return (s { Annex.cachedgitenv = cache }, r)
Just _ -> liftIO $ addindex g
addindex g = do
f <- indexEnvVal $ case i of
AnnexIndexFile -> gitAnnexIndex g
ViewIndexFile -> gitAnnexViewIndex g
g' <- addGitEnv g indexEnv f
return (g', f)
restoregitenv g g' = g' { gitEnv = gitEnv g }
{- Runs an action using a different git work tree.
-
- Smudge and clean filters are disabled in this work tree. -}
withWorkTree :: FilePath -> Annex a -> Annex a
withWorkTree d a = withAltRepo
(\g -> return $ (g { location = modlocation (location g), gitGlobalOpts = gitGlobalOpts g ++ bypassSmudgeConfig }, ()))
(\g g' -> g' { location = location g, gitGlobalOpts = gitGlobalOpts g })
(const a)
where
modlocation l@(Local {}) = l { worktree = Just (toRawFilePath d) }
modlocation _ = giveup "withWorkTree of non-local git repo"
{- Runs an action with the git index file and HEAD, and a few other
- files that are related to the work tree coming from an overlay
- directory other than the usual. This is done by pointing
- GIT_COMMON_DIR at the regular git directory, and GIT_DIR at the
- overlay directory.
-
- Needs git 2.2.0 or newer.
-}
withWorkTreeRelated :: FilePath -> Annex a -> Annex a
withWorkTreeRelated d a = withAltRepo modrepo unmodrepo (const a)
where
modrepo g = liftIO $ do
g' <- addGitEnv g "GIT_COMMON_DIR" . fromRawFilePath
=<< absPath (localGitDir g)
g'' <- addGitEnv g' "GIT_DIR" d
return (g'' { gitEnvOverridesGitDir = True }, ())
unmodrepo g g' = g'
{ gitEnv = gitEnv g
, gitEnvOverridesGitDir = gitEnvOverridesGitDir g
}
withAltRepo
:: (Repo -> Annex (Repo, t))
-- ^ modify Repo
-> (Repo -> Repo -> Repo)
-- ^ undo modifications; first Repo is the original and second
-- is the one after running the action.
-> (t -> Annex a)
-> Annex a
withAltRepo modrepo unmodrepo a = do
g <- gitRepo
(g', t) <- modrepo g
q <- Annex.Queue.get
v <- tryNonAsync $ do
Annex.changeState $ \s -> s
{ Annex.repo = g'
-- Start a separate queue for any changes made
-- with the modified repo.
, Annex.repoqueue = Nothing
}
a t
void $ tryNonAsync Annex.Queue.flush
Annex.changeState $ \s -> s
{ Annex.repo = unmodrepo g (Annex.repo s)
, Annex.repoqueue = Just q
}
either E.throw return v