414 lines
13 KiB
Haskell
414 lines
13 KiB
Haskell
{- git-annex file content managing
|
|
-
|
|
- Copyright 2010 Joey Hess <joey@kitenet.net>
|
|
-
|
|
- Licensed under the GNU GPL version 3 or higher.
|
|
-}
|
|
|
|
module Annex.Content (
|
|
inAnnex,
|
|
inAnnexSafe,
|
|
lockContent,
|
|
calcGitLink,
|
|
logStatus,
|
|
getViaTmp,
|
|
getViaTmpUnchecked,
|
|
withTmp,
|
|
checkDiskSpace,
|
|
moveAnnex,
|
|
removeAnnex,
|
|
fromAnnex,
|
|
moveBad,
|
|
getKeysPresent,
|
|
saveState,
|
|
downloadUrl,
|
|
preseedTmp,
|
|
freezeContent,
|
|
thawContent,
|
|
freezeContentDir,
|
|
) where
|
|
|
|
import System.IO.Unsafe (unsafeInterleaveIO)
|
|
|
|
import Common.Annex
|
|
import Logs.Location
|
|
import Annex.UUID
|
|
import qualified Git
|
|
import qualified Git.Config
|
|
import qualified Annex
|
|
import qualified Annex.Queue
|
|
import qualified Annex.Branch
|
|
import Utility.DiskFree
|
|
import Utility.FileMode
|
|
import qualified Utility.Url as Url
|
|
import Types.Key
|
|
import Utility.DataUnits
|
|
import Utility.CopyFile
|
|
import Config
|
|
import Annex.Exception
|
|
import Git.SharedRepository
|
|
import Annex.Perms
|
|
|
|
{- Checks if a given key's content is currently present. -}
|
|
inAnnex :: Key -> Annex Bool
|
|
inAnnex = inAnnex' doesFileExist
|
|
inAnnex' :: (FilePath -> IO a) -> Key -> Annex a
|
|
inAnnex' a key = do
|
|
whenM (fromRepo Git.repoIsUrl) $
|
|
error "inAnnex cannot check remote repo"
|
|
inRepo $ \g -> gitAnnexLocation key g >>= a
|
|
|
|
{- A safer check; the key's content must not only be present, but
|
|
- is not in the process of being removed. -}
|
|
inAnnexSafe :: Key -> Annex (Maybe Bool)
|
|
inAnnexSafe = inAnnex' $ \f -> openforlock f >>= check
|
|
where
|
|
openforlock f = catchMaybeIO $
|
|
openFd f ReadOnly Nothing defaultFileFlags
|
|
check Nothing = return is_missing
|
|
check (Just h) = do
|
|
v <- getLock h (ReadLock, AbsoluteSeek, 0, 0)
|
|
closeFd h
|
|
return $ case v of
|
|
Just _ -> is_locked
|
|
Nothing -> is_unlocked
|
|
is_locked = Nothing
|
|
is_unlocked = Just True
|
|
is_missing = Just False
|
|
|
|
{- Content is exclusively locked while running an action that might remove
|
|
- it. (If the content is not present, no locking is done.) -}
|
|
lockContent :: Key -> Annex a -> Annex a
|
|
lockContent key a = do
|
|
file <- inRepo $ gitAnnexLocation key
|
|
bracketIO (openforlock file >>= lock) unlock a
|
|
where
|
|
{- Since files are stored with the write bit disabled, have
|
|
- to fiddle with permissions to open for an exclusive lock. -}
|
|
openforlock f = catchMaybeIO $ ifM (doesFileExist f)
|
|
( withModifiedFileMode f
|
|
(`unionFileModes` ownerWriteMode)
|
|
open
|
|
, open
|
|
)
|
|
where
|
|
open = openFd f ReadWrite Nothing defaultFileFlags
|
|
lock Nothing = return Nothing
|
|
lock (Just fd) = do
|
|
v <- tryIO $ setLock fd (WriteLock, AbsoluteSeek, 0, 0)
|
|
case v of
|
|
Left _ -> error "content is locked"
|
|
Right _ -> return $ Just fd
|
|
unlock Nothing = noop
|
|
unlock (Just l) = closeFd l
|
|
|
|
{- Calculates the relative path to use to link a file to a key. -}
|
|
calcGitLink :: FilePath -> Key -> Annex FilePath
|
|
calcGitLink file key = do
|
|
cwd <- liftIO getCurrentDirectory
|
|
let absfile = fromMaybe whoops $ absNormPath cwd file
|
|
loc <- inRepo $ gitAnnexLocation key
|
|
return $ relPathDirToFile (parentDir absfile) loc
|
|
where
|
|
whoops = error $ "unable to normalize " ++ file
|
|
|
|
{- Updates the Logs.Location when a key's presence changes in the current
|
|
- repository. -}
|
|
logStatus :: Key -> LogStatus -> Annex ()
|
|
logStatus key status = do
|
|
u <- getUUID
|
|
logChange key u status
|
|
|
|
{- Runs an action, passing it a temporary filename to get,
|
|
- and if the action succeeds, moves the temp file into
|
|
- the annex as a key's content. -}
|
|
getViaTmp :: Key -> (FilePath -> Annex Bool) -> Annex Bool
|
|
getViaTmp key action = do
|
|
tmp <- fromRepo $ gitAnnexTmpLocation key
|
|
|
|
-- Check that there is enough free disk space.
|
|
-- When the temp file already exists, count the space
|
|
-- it is using as free.
|
|
e <- liftIO $ doesFileExist tmp
|
|
alreadythere <- if e
|
|
then fromIntegral . fileSize <$> liftIO (getFileStatus tmp)
|
|
else return 0
|
|
ifM (checkDiskSpace Nothing key alreadythere)
|
|
( do
|
|
when e $ thawContent tmp
|
|
getViaTmpUnchecked key action
|
|
, return False
|
|
)
|
|
|
|
prepTmp :: Key -> Annex FilePath
|
|
prepTmp key = do
|
|
tmp <- fromRepo $ gitAnnexTmpLocation key
|
|
createAnnexDirectory (parentDir tmp)
|
|
return tmp
|
|
|
|
{- Like getViaTmp, but does not check that there is enough disk space
|
|
- for the incoming key. For use when the key content is already on disk
|
|
- and not being copied into place. -}
|
|
getViaTmpUnchecked :: Key -> (FilePath -> Annex Bool) -> Annex Bool
|
|
getViaTmpUnchecked key action = do
|
|
tmp <- prepTmp key
|
|
ifM (action tmp)
|
|
( do
|
|
moveAnnex key tmp
|
|
logStatus key InfoPresent
|
|
return True
|
|
, do
|
|
-- the tmp file is left behind, in case caller wants
|
|
-- to resume its transfer
|
|
return False
|
|
)
|
|
|
|
{- Creates a temp file, runs an action on it, and cleans up the temp file. -}
|
|
withTmp :: Key -> (FilePath -> Annex a) -> Annex a
|
|
withTmp key action = do
|
|
tmp <- prepTmp key
|
|
res <- action tmp
|
|
liftIO $ nukeFile tmp
|
|
return res
|
|
|
|
{- Checks that there is disk space available to store a given key,
|
|
- in a destination (or the annex) printing a warning if not. -}
|
|
checkDiskSpace :: Maybe FilePath -> Key -> Integer -> Annex Bool
|
|
checkDiskSpace destination key alreadythere = do
|
|
reserve <- getDiskReserve
|
|
free <- liftIO . getDiskFree =<< dir
|
|
force <- Annex.getState Annex.force
|
|
case (free, keySize key) of
|
|
(Just have, Just need) -> do
|
|
let ok = (need + reserve <= have + alreadythere) || force
|
|
unless ok $ do
|
|
liftIO $ print (need, reserve, have, alreadythere)
|
|
needmorespace (need + reserve - have - alreadythere)
|
|
return ok
|
|
_ -> return True
|
|
where
|
|
dir = maybe (fromRepo gitAnnexDir) return destination
|
|
needmorespace n =
|
|
warning $ "not enough free space, need " ++
|
|
roughSize storageUnits True n ++
|
|
" more" ++ forcemsg
|
|
forcemsg = " (use --force to override this check or adjust annex.diskreserve)"
|
|
|
|
{- Moves a key's content into .git/annex/objects/
|
|
- In direct mode, moves it to the associated file, or files.
|
|
-
|
|
- What if the key there already has content? This could happen for
|
|
- various reasons; perhaps the same content is being annexed again.
|
|
- Perhaps there has been a hash collision generating the keys.
|
|
-
|
|
- The current strategy is to assume that in this case it's safe to delete
|
|
- one of the two copies of the content; and the one already in the annex
|
|
- is left there, assuming it's the original, canonical copy.
|
|
-
|
|
- I considered being more paranoid, and checking that both files had
|
|
- the same content. Decided against it because A) users explicitly choose
|
|
- a backend based on its hashing properties and so if they're dealing
|
|
- with colliding files it's their own fault and B) adding such a check
|
|
- would not catch all cases of colliding keys. For example, perhaps
|
|
- a remote has a key; if it's then added again with different content then
|
|
- the overall system now has two different peices of content for that
|
|
- key, and one of them will probably get deleted later. So, adding the
|
|
- check here would only raise expectations that git-annex cannot truely
|
|
- meet.
|
|
-}
|
|
moveAnnex :: Key -> FilePath -> Annex ()
|
|
moveAnnex key src = ifM isDirect
|
|
( storefiles =<< associatedFiles key
|
|
, storeobject
|
|
)
|
|
where
|
|
storeobject = do
|
|
dest <- inRepo $ gitAnnexLocation key
|
|
ifM (liftIO $ doesFileExist dest)
|
|
( liftIO $ removeFile src
|
|
, do
|
|
createContentDir dest
|
|
liftIO $ moveFile src dest
|
|
freezeContent dest
|
|
freezeContentDir dest
|
|
)
|
|
storefiles [] = storeobject
|
|
storefiles (dest:fs) = do
|
|
thawContent src
|
|
liftIO $ replacefile dest $ moveFile src
|
|
liftIO $ forM_ fs $ \f -> replacefile f $ createLink dest
|
|
replacefile file a = do
|
|
{- Remove any symlink or existing file. -}
|
|
r <- tryIO $ removeFile file
|
|
{- Only need to create parent directory if file did not exist. -}
|
|
case r of
|
|
Left _ -> createDirectoryIfMissing True (parentDir file)
|
|
_ -> noop
|
|
a file
|
|
|
|
{- Files in the tree that are associated with a key.
|
|
- For use in direct mode.
|
|
-
|
|
- When no known associated files exist, returns the gitAnnexLocation. -}
|
|
associatedFiles :: Key -> Annex [FilePath]
|
|
associatedFiles key = do
|
|
mapping <- inRepo $ gitAnnexMapping key
|
|
files <- liftIO $ catchDefaultIO [] $ lines <$> readFile mapping
|
|
if null files
|
|
then do
|
|
l <- inRepo $ gitAnnexLocation key
|
|
return [l]
|
|
else do
|
|
top <- fromRepo Git.repoPath
|
|
return $ map (top </>) files
|
|
|
|
withObjectLoc :: Key -> ((FilePath, FilePath) -> Annex a) -> Annex a
|
|
withObjectLoc key a = do
|
|
file <- inRepo $ gitAnnexLocation key
|
|
let dir = parentDir file
|
|
a (dir, file)
|
|
|
|
cleanObjectLoc :: Key -> Annex ()
|
|
cleanObjectLoc key = do
|
|
file <- inRepo $ gitAnnexLocation key
|
|
liftIO $ removeparents file (3 :: Int)
|
|
where
|
|
removeparents _ 0 = noop
|
|
removeparents file n = do
|
|
let dir = parentDir file
|
|
maybe noop (const $ removeparents dir (n-1))
|
|
<=< catchMaybeIO $ removeDirectory dir
|
|
|
|
{- Removes a key's file from .git/annex/objects/ -}
|
|
removeAnnex :: Key -> Annex ()
|
|
removeAnnex key = withObjectLoc key $ \(dir, file) -> do
|
|
liftIO $ do
|
|
allowWrite dir
|
|
removeFile file
|
|
cleanObjectLoc key
|
|
|
|
{- Moves a key's file out of .git/annex/objects/ -}
|
|
fromAnnex :: Key -> FilePath -> Annex ()
|
|
fromAnnex key dest = withObjectLoc key $ \(dir, file) -> do
|
|
liftIO $ allowWrite dir
|
|
thawContent file
|
|
liftIO $ moveFile file dest
|
|
cleanObjectLoc key
|
|
|
|
{- Moves a key out of .git/annex/objects/ into .git/annex/bad, and
|
|
- returns the file it was moved to. -}
|
|
moveBad :: Key -> Annex FilePath
|
|
moveBad key = do
|
|
src <- inRepo $ gitAnnexLocation key
|
|
bad <- fromRepo gitAnnexBadDir
|
|
let dest = bad </> takeFileName src
|
|
createAnnexDirectory (parentDir dest)
|
|
liftIO $ do
|
|
allowWrite (parentDir src)
|
|
moveFile src dest
|
|
cleanObjectLoc key
|
|
logStatus key InfoMissing
|
|
return dest
|
|
|
|
{- List of keys whose content exists in .git/annex/objects/ -}
|
|
getKeysPresent :: Annex [Key]
|
|
getKeysPresent = liftIO . traverse (2 :: Int) =<< fromRepo gitAnnexObjectDir
|
|
where
|
|
traverse depth dir = do
|
|
contents <- catchDefaultIO [] (dirContents dir)
|
|
if depth == 0
|
|
then continue (mapMaybe (fileKey . takeFileName) contents) []
|
|
else do
|
|
let deeper = traverse (depth - 1)
|
|
continue [] (map deeper contents)
|
|
continue keys [] = return keys
|
|
continue keys (a:as) = do
|
|
{- Force lazy traversal with unsafeInterleaveIO. -}
|
|
morekeys <- unsafeInterleaveIO a
|
|
continue (morekeys++keys) as
|
|
|
|
{- Things to do to record changes to content when shutting down.
|
|
-
|
|
- It's acceptable to avoid committing changes to the branch,
|
|
- especially if performing a short-lived action.
|
|
-}
|
|
saveState :: Bool -> Annex ()
|
|
saveState nocommit = doSideAction $ do
|
|
Annex.Queue.flush
|
|
unless nocommit $
|
|
whenM alwayscommit $
|
|
Annex.Branch.commit "update"
|
|
where
|
|
alwayscommit = fromMaybe True . Git.Config.isTrue
|
|
<$> getConfig (annexConfig "alwayscommit") ""
|
|
|
|
{- Downloads content from any of a list of urls. -}
|
|
downloadUrl :: [Url.URLString] -> FilePath -> Annex Bool
|
|
downloadUrl urls file = do
|
|
o <- map Param . words <$> getConfig (annexConfig "web-options") ""
|
|
headers <- getHttpHeaders
|
|
liftIO $ anyM (\u -> Url.download u headers o file) urls
|
|
|
|
{- Copies a key's content, when present, to a temp file.
|
|
- This is used to speed up some rsyncs. -}
|
|
preseedTmp :: Key -> FilePath -> Annex Bool
|
|
preseedTmp key file = go =<< inAnnex key
|
|
where
|
|
go False = return False
|
|
go True = do
|
|
ok <- copy
|
|
when ok $ thawContent file
|
|
return ok
|
|
copy = ifM (liftIO $ doesFileExist file)
|
|
( return True
|
|
, do
|
|
s <- inRepo $ gitAnnexLocation key
|
|
liftIO $ copyFileExternal s file
|
|
)
|
|
|
|
{- Blocks writing to an annexed file. The file is made unwritable
|
|
- to avoid accidental edits. core.sharedRepository may change
|
|
- who can read it. -}
|
|
freezeContent :: FilePath -> Annex ()
|
|
freezeContent file = liftIO . go =<< fromRepo getSharedRepository
|
|
where
|
|
go GroupShared = modifyFileMode file $
|
|
removeModes writeModes .
|
|
addModes [ownerReadMode, groupReadMode]
|
|
go AllShared = modifyFileMode file $
|
|
removeModes writeModes .
|
|
addModes readModes
|
|
go _ = preventWrite file
|
|
|
|
{- Allows writing to an annexed file that freezeContent was called on
|
|
- before. -}
|
|
thawContent :: FilePath -> Annex ()
|
|
thawContent file = liftIO . go =<< fromRepo getSharedRepository
|
|
where
|
|
go GroupShared = groupWriteRead file
|
|
go AllShared = groupWriteRead file
|
|
go _ = allowWrite file
|
|
|
|
{- Blocks writing to the directory an annexed file is in, to prevent the
|
|
- file accidentially being deleted. However, if core.sharedRepository
|
|
- is set, this is not done, since the group must be allowed to delete the
|
|
- file.
|
|
-}
|
|
freezeContentDir :: FilePath -> Annex ()
|
|
freezeContentDir file = liftIO . go =<< fromRepo getSharedRepository
|
|
where
|
|
dir = parentDir file
|
|
go GroupShared = groupWriteRead dir
|
|
go AllShared = groupWriteRead dir
|
|
go _ = preventWrite dir
|
|
|
|
{- Makes the directory tree to store an annexed file's content,
|
|
- with appropriate permissions on each level. -}
|
|
createContentDir :: FilePath -> Annex ()
|
|
createContentDir dest = do
|
|
unlessM (liftIO $ doesDirectoryExist dir) $
|
|
createAnnexDirectory dir
|
|
-- might have already existed with restricted perms
|
|
liftIO $ allowWrite dir
|
|
where
|
|
dir = parentDir dest
|