Avoid re-checksumming when migrating from hash to hashE backend. Closes: #774494

This commit is contained in:
Joey Hess 2015-01-04 12:33:10 -04:00
parent e26e26fb32
commit 73928c2274
4 changed files with 15 additions and 6 deletions

View file

@ -1,4 +1,4 @@
{- git-annex hashing backends
{- git-tnnex hashing backends
-
- Copyright 2011-2013 Joey Hess <joey@kitenet.net>
-
@ -132,13 +132,20 @@ needsUpgrade :: Key -> Bool
needsUpgrade key = "\\" `isPrefixOf` keyHash key ||
any (not . validExtension) (takeExtensions $ keyName key)
{- Fast migration from hashE to hash backend. (Optimisation) -}
trivialMigrate :: Key -> Backend -> Maybe Key
trivialMigrate oldkey newbackend
trivialMigrate :: Key -> Backend -> AssociatedFile -> Maybe Key
trivialMigrate oldkey newbackend afile
{- Fast migration from hashE to hash backend. -}
| keyBackendName oldkey == name newbackend ++ "E" = Just $ oldkey
{ keyName = keyHash oldkey
, keyBackendName = name newbackend
}
{- Fast migration from hash to hashE backend. -}
| keyBackendName oldkey ++"E" == name newbackend = case afile of
Nothing -> Nothing
Just file -> Just $ oldkey
{ keyName = keyHash oldkey ++ selectExtension file
, keyBackendName = name newbackend
}
| otherwise = Nothing
hashFile :: Hash -> FilePath -> Integer -> Annex String