git-annex/Seek.hs
Joey Hess 34c8af74ba fix inversion of control in CommandSeek (no behavior changes)
I've been disliking how the command seek actions were written for some
time, with their inversion of control and ugly workarounds.

The last straw to fix it was sync --content, which didn't fit the
Annex [CommandStart] interface well at all. I have not yet made it take
advantage of the changed interface though.

The crucial change, and probably why I didn't do it this way from the
beginning, is to make each CommandStart action be run with exceptions
caught, and if it fails, increment a failure counter in annex state.
So I finally remove the very first code I wrote for git-annex, which
was before I had exception handling in the Annex monad, and so ran outside
that monad, passing state explicitly as it ran each CommandStart action.

This was a real slog from 1 to 5 am.

Test suite passes.

Memory usage is lower than before, sometimes by a couple of megabytes, and
remains constant, even when running in a large repo, and even when
repeatedly failing and incrementing the error counter. So no accidental
laziness space leaks.

Wall clock speed is identical, even in large repos.

This commit was sponsored by an anonymous bitcoiner.
2014-01-20 04:57:36 -04:00

177 lines
6.2 KiB
Haskell

{- git-annex command seeking
-
- These functions find appropriate files or other things based on
- the values a user passes to a command, and prepare actions operating
- on them.
-
- Copyright 2010-2014 Joey Hess <joey@kitenet.net>
-
- Licensed under the GNU GPL version 3 or higher.
-}
module Seek where
import System.PosixCompat.Files
import Common.Annex
import Types.Command
import Types.Key
import Types.FileMatcher
import qualified Annex
import qualified Git
import qualified Git.Command
import qualified Git.LsFiles as LsFiles
import qualified Limit
import qualified Option
import Logs.Location
import Logs.Unused
import Annex.CatFile
import RunCommand
withFilesInGit :: (FilePath -> CommandStart) -> CommandSeek
withFilesInGit a params = seekActions $ prepFiltered a $
seekHelper LsFiles.inRepo params
withFilesNotInGit :: (FilePath -> CommandStart) -> CommandSeek
withFilesNotInGit a params = do
{- dotfiles are not acted on unless explicitly listed -}
files <- filter (not . dotfile) <$>
seekunless (null ps && not (null params)) ps
dotfiles <- seekunless (null dotps) dotps
seekActions $ prepFiltered a $
return $ concat $ segmentPaths params (files++dotfiles)
where
(dotps, ps) = partition dotfile params
seekunless True _ = return []
seekunless _ l = do
force <- Annex.getState Annex.force
g <- gitRepo
liftIO $ Git.Command.leaveZombie <$> LsFiles.notInRepo force l g
withPathContents :: ((FilePath, FilePath) -> CommandStart) -> CommandSeek
withPathContents a params = seekActions $
map a . concat <$> liftIO (mapM get params)
where
get p = ifM (isDirectory <$> getFileStatus p)
( map (\f -> (f, makeRelative (parentDir p) f))
<$> dirContentsRecursiveSkipping (".git" `isSuffixOf`) True p
, return [(p, takeFileName p)]
)
withWords :: ([String] -> CommandStart) -> CommandSeek
withWords a params = seekActions $ return [a params]
withStrings :: (String -> CommandStart) -> CommandSeek
withStrings a params = seekActions $ return $ map a params
withPairs :: ((String, String) -> CommandStart) -> CommandSeek
withPairs a params = seekActions $ return $ map a $ pairs [] params
where
pairs c [] = reverse c
pairs c (x:y:xs) = pairs ((x,y):c) xs
pairs _ _ = error "expected pairs"
withFilesToBeCommitted :: (String -> CommandStart) -> CommandSeek
withFilesToBeCommitted a params = seekActions $ prepFiltered a $
seekHelper LsFiles.stagedNotDeleted params
withFilesUnlocked :: (FilePath -> CommandStart) -> CommandSeek
withFilesUnlocked = withFilesUnlocked' LsFiles.typeChanged
withFilesUnlockedToBeCommitted :: (FilePath -> CommandStart) -> CommandSeek
withFilesUnlockedToBeCommitted = withFilesUnlocked' LsFiles.typeChangedStaged
{- Unlocked files have changed type from a symlink to a regular file.
-
- Furthermore, unlocked files used to be a git-annex symlink,
- not some other sort of symlink.
-}
withFilesUnlocked' :: ([FilePath] -> Git.Repo -> IO ([FilePath], IO Bool)) -> (FilePath -> CommandStart) -> CommandSeek
withFilesUnlocked' typechanged a params = seekActions $
prepFiltered a unlockedfiles
where
check f = liftIO (notSymlink f) <&&>
(isJust <$> catKeyFile f <||> isJust <$> catKeyFileHEAD f)
unlockedfiles = filterM check =<< seekHelper typechanged params
{- Finds files that may be modified. -}
withFilesMaybeModified :: (FilePath -> CommandStart) -> CommandSeek
withFilesMaybeModified a params = seekActions $
prepFiltered a $ seekHelper LsFiles.modified params
withKeys :: (Key -> CommandStart) -> CommandSeek
withKeys a params = seekActions $ return $ map (a . parse) params
where
parse p = fromMaybe (error "bad key") $ file2key p
{- Gets the value of a field options, which is fed into
- a conversion function.
-}
getOptionField :: Option -> (Maybe String -> Annex a) -> Annex a
getOptionField option converter = converter <=< Annex.getField $ Option.name option
getOptionFlag :: Option -> Annex Bool
getOptionFlag option = Annex.getFlag (Option.name option)
withNothing :: CommandStart -> CommandSeek
withNothing a [] = seekActions $ return [a]
withNothing _ _ = error "This command takes no parameters."
{- If --all is specified, or in a bare repo, runs an action on all
- known keys.
-
- If --unused is specified, runs an action on all keys found by
- the last git annex unused scan.
-
- Otherwise, fall back to a regular CommandSeek action on
- whatever params were passed. -}
withKeyOptions :: (Key -> CommandStart) -> CommandSeek -> CommandSeek
withKeyOptions keyop fallbackop params = do
bare <- fromRepo Git.repoIsLocalBare
allkeys <- Annex.getFlag "all"
unused <- Annex.getFlag "unused"
auto <- Annex.getState Annex.auto
case (allkeys || bare , unused, auto ) of
(True , False , False) -> go loggedKeys
(False , True , False) -> go unusedKeys
(True , True , _ )
| bare && not allkeys -> go unusedKeys
| otherwise -> error "Cannot use --all with --unused."
(False , False , _ ) -> fallbackop params
(_ , _ , True )
| bare -> error "Cannot use --auto in a bare repository."
| otherwise -> error "Cannot use --auto with --all or --unused."
where
go a = do
unless (null params) $
error "Cannot mix --all or --unused with file names."
matcher <- Limit.getMatcher
seekActions $ map (process matcher) <$> a
process matcher k = ifM (matcher $ MatchingKey k)
( keyop k , return Nothing)
prepFiltered :: (FilePath -> CommandStart) -> Annex [FilePath] -> Annex [CommandStart]
prepFiltered a fs = do
matcher <- Limit.getMatcher
map (process matcher) <$> fs
where
process matcher f = ifM (matcher $ MatchingFile $ FileInfo f f)
( a f , return Nothing )
seekActions :: Annex [CommandStart] -> Annex ()
seekActions gen = do
as <- gen
mapM_ commandAction as
seekHelper :: ([FilePath] -> Git.Repo -> IO ([FilePath], IO Bool)) -> [FilePath] -> Annex [FilePath]
seekHelper a params = do
ll <- inRepo $ \g ->
runSegmentPaths (\fs -> Git.Command.leaveZombie <$> a fs g) params
{- Show warnings only for files/directories that do not exist. -}
forM_ (map fst $ filter (null . snd) $ zip params ll) $ \p ->
unlessM (isJust <$> liftIO (catchMaybeIO $ getSymbolicLinkStatus p)) $
fileNotFound p
return $ concat ll
notSymlink :: FilePath -> IO Bool
notSymlink f = liftIO $ not . isSymbolicLink <$> getSymbolicLinkStatus f