git-annex/Command/Unused.hs
Joey Hess 2566eb85fe fsck: Now works in bare repositories.
Checks location log information, and file contents.

Does not check that numcopies is satisfied, as .gitattributes information
about numcopies is not available in a bare repository. In practice, that
should not be a problem, since fsck is also run in a checkout and will
check numcopies there.
2011-10-29 18:03:28 -04:00

237 lines
7.2 KiB
Haskell

{- git-annex command
-
- Copyright 2010-2011 Joey Hess <joey@kitenet.net>
-
- Licensed under the GNU GPL version 3 or higher.
-}
{-# LANGUAGE BangPatterns #-}
module Command.Unused where
import qualified Data.Set as S
import qualified Data.ByteString.Lazy.Char8 as L
import Common.Annex
import Command
import Annex.Content
import Utility.FileMode
import Utility.TempFile
import Logs.Location
import qualified Annex
import qualified Git
import qualified Git.LsFiles as LsFiles
import qualified Git.LsTree as LsTree
import qualified Backend
import qualified Remote
import qualified Annex.Branch
import Annex.CatFile
def :: [Command]
def = [dontCheck fromOpt $ command "unused" paramNothing seek
"look for unused file content"]
seek :: [CommandSeek]
seek = [withNothing start]
{- Finds unused content in the annex. -}
start :: CommandStart
start = notBareRepo $ do
from <- Annex.getState Annex.fromremote
let (name, action) = case from of
Nothing -> (".", checkUnused)
Just "." -> (".", checkUnused)
Just n -> (n, checkRemoteUnused n)
showStart "unused" name
next action
checkUnused :: CommandPerform
checkUnused = do
(unused, stalebad, staletmp) <- unusedKeys
_ <- list "" unusedMsg unused 0 >>=
list "bad" staleBadMsg stalebad >>=
list "tmp" staleTmpMsg staletmp
next $ return True
where
list file msg l c = do
let unusedlist = number c l
unless (null l) $ showLongNote $ msg unusedlist
writeUnusedFile file unusedlist
return $ c + length l
checkRemoteUnused :: String -> CommandPerform
checkRemoteUnused name = do
checkRemoteUnused' =<< Remote.byName name
next $ return True
checkRemoteUnused' :: Remote.Remote Annex -> Annex ()
checkRemoteUnused' r = do
showAction "checking for unused data"
remotehas <- loggedKeysFor (Remote.uuid r)
remoteunused <- excludeReferenced remotehas
let list = number 0 remoteunused
writeUnusedFile "" list
unless (null remoteunused) $ showLongNote $ remoteUnusedMsg r list
writeUnusedFile :: FilePath -> [(Int, Key)] -> Annex ()
writeUnusedFile prefix l = do
g <- gitRepo
liftIO $ viaTmp writeFile (gitAnnexUnusedLog prefix g) $
unlines $ map (\(n, k) -> show n ++ " " ++ show k) l
table :: [(Int, Key)] -> [String]
table l = " NUMBER KEY" : map cols l
where
cols (n,k) = " " ++ pad 6 (show n) ++ " " ++ show k
pad n s = s ++ replicate (n - length s) ' '
number :: Int -> [a] -> [(Int, a)]
number _ [] = []
number n (x:xs) = (n+1, x) : number (n+1) xs
staleTmpMsg :: [(Int, Key)] -> String
staleTmpMsg t = unlines $
["Some partially transferred data exists in temporary files:"]
++ table t ++ [dropMsg Nothing]
staleBadMsg :: [(Int, Key)] -> String
staleBadMsg t = unlines $
["Some corrupted files have been preserved by fsck, just in case:"]
++ table t ++ [dropMsg Nothing]
unusedMsg :: [(Int, Key)] -> String
unusedMsg u = unusedMsg' u
["Some annexed data is no longer used by any files:"]
[dropMsg Nothing]
unusedMsg' :: [(Int, Key)] -> [String] -> [String] -> String
unusedMsg' u header trailer = unlines $
header ++
table u ++
["(To see where data was previously used, try: git log --stat -S'KEY')"] ++
trailer
remoteUnusedMsg :: Remote.Remote Annex -> [(Int, Key)] -> String
remoteUnusedMsg r u = unusedMsg' u
["Some annexed data on " ++ name ++ " is not used by any files:"]
[dropMsg $ Just r]
where
name = Remote.name r
dropMsg :: Maybe (Remote.Remote Annex) -> String
dropMsg Nothing = dropMsg' ""
dropMsg (Just r) = dropMsg' $ " --from " ++ Remote.name r
dropMsg' :: String -> String
dropMsg' s = "\nTo remove unwanted data: git-annex dropunused" ++ s ++ " NUMBER\n"
{- Finds keys whose content is present, but that do not seem to be used
- by any files in the git repo, or that are only present as bad or tmp
- files. -}
unusedKeys :: Annex ([Key], [Key], [Key])
unusedKeys = do
fast <- Annex.getState Annex.fast
if fast
then do
showNote "fast mode enabled; only finding stale files"
tmp <- staleKeys gitAnnexTmpDir
bad <- staleKeys gitAnnexBadDir
return ([], bad, tmp)
else do
showAction "checking for unused data"
present <- getKeysPresent
unused <- excludeReferenced present
staletmp <- staleKeysPrune gitAnnexTmpDir present
stalebad <- staleKeysPrune gitAnnexBadDir present
return (unused, stalebad, staletmp)
{- Finds keys in the list that are not referenced in the git repository. -}
excludeReferenced :: [Key] -> Annex [Key]
excludeReferenced [] = return [] -- optimisation
excludeReferenced l = do
g <- gitRepo
c <- liftIO $ Git.pipeRead g [Param "show-ref"]
removewith (getKeysReferenced : map getKeysReferencedInGit (refs c))
(S.fromList l)
where
-- Skip the git-annex branches, and get all other unique refs.
refs = map last .
nubBy cmpheads .
filter ourbranches .
map words . lines . L.unpack
cmpheads a b = head a == head b
ourbranchend = '/' : Annex.Branch.name
ourbranches ws = not $ ourbranchend `isSuffixOf` last ws
removewith [] s = return $ S.toList s
removewith (a:as) s
| s == S.empty = return [] -- optimisation
| otherwise = do
referenced <- a
let !s' = s `S.difference` S.fromList referenced
removewith as s'
{- Finds items in the first, smaller list, that are not
- present in the second, larger list.
-
- Constructing a single set, of the list that tends to be
- smaller, appears more efficient in both memory and CPU
- than constructing and taking the S.difference of two sets. -}
exclude :: Ord a => [a] -> [a] -> [a]
exclude [] _ = [] -- optimisation
exclude smaller larger = S.toList $ remove larger $ S.fromList smaller
where
remove a b = foldl (flip S.delete) b a
{- List of keys referenced by symlinks in the git repo. -}
getKeysReferenced :: Annex [Key]
getKeysReferenced = do
g <- gitRepo
files <- liftIO $ LsFiles.inRepo g [Git.workTree g]
keypairs <- mapM Backend.lookupFile files
return $ map fst $ catMaybes keypairs
{- List of keys referenced by symlinks in a git ref. -}
getKeysReferencedInGit :: String -> Annex [Key]
getKeysReferencedInGit ref = do
showAction $ "checking " ++ Git.refDescribe ref
g <- gitRepo
findkeys [] =<< liftIO (LsTree.lsTree g ref)
where
findkeys c [] = return c
findkeys c (l:ls)
| isSymLink (LsTree.mode l) = do
content <- catFile ref $ LsTree.file l
case fileKey (takeFileName content) of
Nothing -> findkeys c ls
Just k -> findkeys (k:c) ls
| otherwise = findkeys c ls
{- Looks in the specified directory for bad/tmp keys, and returns a list
- of those that might still have value, or might be stale and removable.
-
- When a list of presently available keys is provided, stale keys
- that no longer have value are deleted.
-}
staleKeysPrune :: (Git.Repo -> FilePath) -> [Key] -> Annex [Key]
staleKeysPrune dirspec present = do
contents <- staleKeys dirspec
let stale = contents `exclude` present
let dups = contents `exclude` stale
g <- gitRepo
let dir = dirspec g
liftIO $ forM_ dups $ \t -> removeFile $ dir </> keyFile t
return stale
staleKeys :: (Git.Repo -> FilePath) -> Annex [Key]
staleKeys dirspec = do
g <- gitRepo
let dir = dirspec g
exists <- liftIO $ doesDirectoryExist dir
if not exists
then return []
else do
contents <- liftIO $ getDirectoryContents dir
files <- liftIO $ filterM doesFileExist $
map (dir </>) contents
return $ mapMaybe (fileKey . takeFileName) files