git-annex/Annex/Branch/Transitions.hs
Joey Hess 40ecf58d4b
update licenses from GPL to AGPL
This does not change the overall license of the git-annex program, which
was already AGPL due to a number of sources files being AGPL already.

Legally speaking, I'm adding a new license under which these files are
now available; I already released their current contents under the GPL
license. Now they're dual licensed GPL and AGPL. However, I intend
for all my future changes to these files to only be released under the
AGPL license, and I won't be tracking the dual licensing status, so I'm
simply changing the license statement to say it's AGPL.

(In some cases, others wrote parts of the code of a file and released it
under the GPL; but in all cases I have contributed a significant portion
of the code in each file and it's that code that is getting the AGPL
license; the GPL license of other contributors allows combining with
AGPL code.)
2019-03-13 15:48:14 -04:00

87 lines
3 KiB
Haskell

{- git-annex branch transitions
-
- Copyright 2013-2019 Joey Hess <id@joeyh.name>
-
- Licensed under the GNU AGPL version 3 or higher.
-}
module Annex.Branch.Transitions (
FileTransition(..),
getTransitionCalculator
) where
import Common
import Logs
import Logs.Transitions
import qualified Logs.UUIDBased as UUIDBased
import qualified Logs.Presence.Pure as Presence
import qualified Logs.Chunk.Pure as Chunk
import qualified Logs.MetaData.Pure as MetaData
import Types.TrustLevel
import Types.UUID
import Types.MetaData
import qualified Data.Map as M
import qualified Data.Set as S
import qualified Data.ByteString.Lazy as L
import qualified Data.Attoparsec.ByteString.Lazy as A
import Data.ByteString.Builder
data FileTransition
= ChangeFile Builder
| RemoveFile
| PreserveFile
type TransitionCalculator = FilePath -> L.ByteString -> TrustMap -> FileTransition
getTransitionCalculator :: Transition -> Maybe TransitionCalculator
getTransitionCalculator ForgetGitHistory = Nothing
getTransitionCalculator ForgetDeadRemotes = Just dropDead
dropDead :: FilePath -> L.ByteString -> TrustMap -> FileTransition
dropDead f content trustmap = case getLogVariety f of
Just OldUUIDBasedLog
-- Don't remove the dead repo from the trust log,
-- because git remotes may still exist, and they need
-- to still know it's dead.
| f == trustLog -> PreserveFile
| otherwise -> ChangeFile $
UUIDBased.buildLogOld byteString $
dropDeadFromMapLog trustmap id $
UUIDBased.parseLogOld A.takeByteString content
Just NewUUIDBasedLog -> ChangeFile $
UUIDBased.buildLogNew byteString $
dropDeadFromMapLog trustmap id $
UUIDBased.parseLogNew A.takeByteString content
Just (ChunkLog _) -> ChangeFile $
Chunk.buildLog $ dropDeadFromMapLog trustmap fst $ Chunk.parseLog content
Just (PresenceLog _) ->
let newlog = Presence.compactLog $
dropDeadFromPresenceLog trustmap $ Presence.parseLog content
in if null newlog
then RemoveFile
else ChangeFile $ Presence.buildLog newlog
Just RemoteMetaDataLog ->
let newlog = dropDeadFromRemoteMetaDataLog trustmap $ MetaData.simplifyLog $ MetaData.parseLog content
in if S.null newlog
then RemoveFile
else ChangeFile $ MetaData.buildLog newlog
Just OtherLog -> PreserveFile
Nothing -> PreserveFile
dropDeadFromMapLog :: TrustMap -> (k -> UUID) -> M.Map k v -> M.Map k v
dropDeadFromMapLog trustmap getuuid =
M.filterWithKey $ \k _v -> notDead trustmap getuuid k
{- Presence logs can contain UUIDs or other values. Any line that matches
- a dead uuid is dropped; any other values are passed through. -}
dropDeadFromPresenceLog :: TrustMap -> [Presence.LogLine] -> [Presence.LogLine]
dropDeadFromPresenceLog trustmap =
filter $ notDead trustmap (toUUID . Presence.fromLogInfo . Presence.info)
dropDeadFromRemoteMetaDataLog :: TrustMap -> MetaData.Log MetaData -> MetaData.Log MetaData
dropDeadFromRemoteMetaDataLog trustmap =
MetaData.filterOutEmpty . MetaData.filterRemoteMetaData (notDead trustmap id)
notDead :: TrustMap -> (v -> UUID) -> v -> Bool
notDead trustmap a v = M.findWithDefault def (a v) trustmap /= DeadTrusted