30 lines
758 B
Haskell
30 lines
758 B
Haskell
{- git-annex backend utilities
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-
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- Copyright 2012 Joey Hess <id@joeyh.name>
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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 Backend.Utilities where
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import Data.Hash.MD5
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import Annex.Common
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{- Generates a keyName from an input string. Takes care of sanitizing it.
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- If it's not too long, the full string is used as the keyName.
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- Otherwise, it's truncated, and its md5 is prepended to ensure a unique
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- key. -}
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genKeyName :: String -> String
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genKeyName s
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-- Avoid making keys longer than the length of a SHA256 checksum.
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| bytelen > sha256len =
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truncateFilePath (sha256len - md5len - 1) s' ++ "-" ++ md5s (Str s)
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| otherwise = s'
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where
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s' = preSanitizeKeyName s
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bytelen = length (decodeW8 s')
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sha256len = 64
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md5len = 32
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