e953be11af
Since _encodeFilePath generates a String that doesn't use the filesystem encoding, when this exception is caught, we know we already have such a String, and can just return it as-is.
39 lines
1.2 KiB
Haskell
39 lines
1.2 KiB
Haskell
{- Simple Base64 encoding of Strings
|
|
-
|
|
- Note that this uses the FileSystemEncoding, so it can be used on Strings
|
|
- that repesent filepaths containing arbitrarily encoded characters.
|
|
-
|
|
- Copyright 2011, 2015 Joey Hess <id@joeyh.name>
|
|
-
|
|
- License: BSD-2-clause
|
|
-}
|
|
|
|
module Utility.Base64 (toB64, fromB64Maybe, fromB64, prop_b64_roundtrips) where
|
|
|
|
import Utility.FileSystemEncoding
|
|
|
|
import qualified "sandi" Codec.Binary.Base64 as B64
|
|
import Data.Maybe
|
|
import qualified Data.ByteString.Lazy as L
|
|
import Data.ByteString.UTF8 (fromString, toString)
|
|
import Data.Char
|
|
|
|
toB64 :: String -> String
|
|
toB64 = toString . B64.encode . L.toStrict . encodeBS
|
|
|
|
fromB64Maybe :: String -> Maybe String
|
|
fromB64Maybe s = either (const Nothing) (Just . decodeBS . L.fromStrict)
|
|
(B64.decode $ fromString s)
|
|
|
|
fromB64 :: String -> String
|
|
fromB64 = fromMaybe bad . fromB64Maybe
|
|
where
|
|
bad = error "bad base64 encoded data"
|
|
|
|
-- Only ascii strings are tested, because an arbitrary string may contain
|
|
-- characters not encoded using the FileSystemEncoding, which would thus
|
|
-- not roundtrip, as fromB64 always generates an output encoded that way.
|
|
prop_b64_roundtrips :: String -> Bool
|
|
prop_b64_roundtrips s
|
|
| all (isAscii) s = s == fromB64 (toB64 s)
|
|
| otherwise = True
|