git-annex/Annex/Content/Direct.hs
Joey Hess 57780cb3a4 Clean up direct mode cache and mapping info when dropping keys.
These files were left behind, and made getKeysPresent find keys that were
not present. It would be expensive to make getKeysPresent check that the
actual key files are present (it just lists the directories). But that's not
needed if we just clean up the stale cache and mapping files.

To handle systems that were in direct mode and got switched back with stale
direct mode files, made cleanObjectLoc remove all files in the key's directory.

git annex unused will still list keys that are gone but for which the stale
direct mode files exists. To deal with that, made dropunused remove the key's
directory even if the key does not seem to be present.
2013-02-07 08:28:40 -04:00

167 lines
4.9 KiB
Haskell

{- git-annex file content managing for direct mode
-
- Copyright 2010,2012 Joey Hess <joey@kitenet.net>
-
- Licensed under the GNU GPL version 3 or higher.
-}
module Annex.Content.Direct (
associatedFiles,
removeAssociatedFile,
addAssociatedFile,
goodContent,
changedFileStatus,
updateCache,
recordedCache,
compareCache,
writeCache,
genCache,
toCache,
Cache(..),
prop_read_show_direct
) where
import Common.Annex
import Annex.Perms
import qualified Git
import Utility.TempFile
import Logs.Location
import System.Posix.Types
{- Absolute FilePaths of Files in the tree that are associated with a key. -}
associatedFiles :: Key -> Annex [FilePath]
associatedFiles key = do
files <- associatedFilesRelative key
top <- fromRepo Git.repoPath
return $ map (top </>) files
{- List of files in the tree that are associated with a key, relative to
- the top of the repo. -}
associatedFilesRelative :: Key -> Annex [FilePath]
associatedFilesRelative key = do
mapping <- inRepo $ gitAnnexMapping key
liftIO $ catchDefaultIO [] $ do
h <- openFile mapping ReadMode
fileEncoding h
lines <$> hGetContents h
{- Changes the associated files information for a key, applying a
- transformation to the list. Returns new associatedFiles value. -}
changeAssociatedFiles :: Key -> ([FilePath] -> [FilePath]) -> Annex [FilePath]
changeAssociatedFiles key transform = do
mapping <- inRepo $ gitAnnexMapping key
files <- associatedFilesRelative key
let files' = transform files
when (files /= files') $ do
createContentDir mapping
liftIO $ viaTmp write mapping $ unlines files'
top <- fromRepo Git.repoPath
return $ map (top </>) files'
where
write file content = do
h <- openFile file WriteMode
fileEncoding h
hPutStr h content
hClose h
{- Removes an associated file. Returns new associatedFiles value. -}
removeAssociatedFile :: Key -> FilePath -> Annex [FilePath]
removeAssociatedFile key file = do
file' <- normaliseAssociatedFile file
fs <- changeAssociatedFiles key $ filter (/= file')
when (null fs) $
logStatus key InfoMissing
return fs
{- Adds an associated file. Returns new associatedFiles value. -}
addAssociatedFile :: Key -> FilePath -> Annex [FilePath]
addAssociatedFile key file = do
file' <- normaliseAssociatedFile file
changeAssociatedFiles key $ \files -> do
if file' `elem` files
then files
else file':files
{- Associated files are always stored relative to the top of the repository.
- The input FilePath is relative to the CWD. -}
normaliseAssociatedFile :: FilePath -> Annex FilePath
normaliseAssociatedFile file = do
top <- fromRepo Git.repoPath
liftIO $ relPathDirToFile top <$> absPath file
{- Checks if a file in the tree, associated with a key, has not been modified.
-
- To avoid needing to fsck the file's content, which can involve an
- expensive checksum, this relies on a cache that contains the file's
- expected mtime and inode.
-}
goodContent :: Key -> FilePath -> Annex Bool
goodContent key file = do
old <- recordedCache key
compareCache file old
changedFileStatus :: Key -> FileStatus -> Annex Bool
changedFileStatus key status = do
old <- recordedCache key
let curr = toCache status
return $ curr /= old
{- Gets the recorded cache for a key. -}
recordedCache :: Key -> Annex (Maybe Cache)
recordedCache key = withCacheFile key $ \cachefile ->
liftIO $ catchDefaultIO Nothing $ readCache <$> readFile cachefile
{- Compares a cache with the current cache for a file. -}
compareCache :: FilePath -> Maybe Cache -> Annex Bool
compareCache file old = do
curr <- liftIO $ genCache file
return $ isJust curr && curr == old
{- Stores a cache of attributes for a file that is associated with a key. -}
updateCache :: Key -> FilePath -> Annex ()
updateCache key file = maybe noop (writeCache key) =<< liftIO (genCache file)
{- Writes a cache for a key. -}
writeCache :: Key -> Cache -> Annex ()
writeCache key cache = withCacheFile key $ \cachefile -> do
createContentDir cachefile
liftIO $ writeFile cachefile $ showCache cache
{- Cache a file's inode, size, and modification time to determine if it's
- been changed. -}
data Cache = Cache FileID FileOffset EpochTime
deriving (Eq, Show)
showCache :: Cache -> String
showCache (Cache inode size mtime) = unwords
[ show inode
, show size
, show mtime
]
readCache :: String -> Maybe Cache
readCache s = case words s of
(inode:size:mtime:_) -> Cache
<$> readish inode
<*> readish size
<*> readish mtime
_ -> Nothing
-- for quickcheck
prop_read_show_direct :: Cache -> Bool
prop_read_show_direct c = readCache (showCache c) == Just c
genCache :: FilePath -> IO (Maybe Cache)
genCache f = catchDefaultIO Nothing $ toCache <$> getFileStatus f
toCache :: FileStatus -> Maybe Cache
toCache s
| isRegularFile s = Just $ Cache
(fileID s)
(fileSize s)
(modificationTime s)
| otherwise = Nothing
withCacheFile :: Key -> (FilePath -> Annex a) -> Annex a
withCacheFile key a = a =<< inRepo (gitAnnexCache key)