39 lines
1.1 KiB
Haskell
39 lines
1.1 KiB
Haskell
{- git-annex key/value backend data type
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-
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- Most things should not need this, using Types instead
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-
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- Copyright 2010 Joey Hess <joey@kitenet.net>
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-
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- Licensed under the GNU GPL version 3 or higher.
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-}
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module BackendClass where
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import Key
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data Backend a = Backend {
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-- name of this backend
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name :: String,
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-- converts a filename to a key
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getKey :: FilePath -> a (Maybe Key),
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-- stores a file's contents to a key
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storeFileKey :: FilePath -> Key -> a Bool,
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-- retrieves a key's contents to a file
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retrieveKeyFile :: Key -> FilePath -> a Bool,
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-- removes a key, optionally checking that enough copies are stored
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-- elsewhere
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removeKey :: Key -> Maybe Int -> a Bool,
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-- checks if a backend is storing the content of a key
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hasKey :: Key -> a Bool,
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-- called during fsck to check a key
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-- (second parameter may be the filename associated with it)
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-- (third parameter may be the number of copies that there should
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-- be of the key)
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fsckKey :: Key -> Maybe FilePath -> Maybe Int -> a Bool
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}
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instance Show (Backend a) where
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show backend = "Backend { name =\"" ++ name backend ++ "\" }"
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instance Eq (Backend a) where
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a == b = name a == name b
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