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Diffstat (limited to '')
-rw-r--r-- | users/Profpatsch/arglib/ArglibNetencode.hs | 25 |
1 files changed, 25 insertions, 0 deletions
diff --git a/users/Profpatsch/arglib/ArglibNetencode.hs b/users/Profpatsch/arglib/ArglibNetencode.hs new file mode 100644 index 000000000000..e4609d26abf5 --- /dev/null +++ b/users/Profpatsch/arglib/ArglibNetencode.hs @@ -0,0 +1,25 @@ +{-# LANGUAGE LambdaCase #-} +{-# LANGUAGE OverloadedStrings #-} +{-# LANGUAGE QuasiQuotes #-} + +module ArglibNetencode where + +import qualified Data.Attoparsec.ByteString as Atto +import Data.Maybe (fromMaybe) +import ExecHelpers +import MyPrelude +import Netencode +import qualified System.Environment as Env +import qualified System.Posix.Env.ByteString as ByteEnv + +arglibNetencode :: CurrentProgramName -> Maybe Text -> IO T +arglibNetencode progName mEnvvar = do + let envvar = mEnvvar & fromMaybe "ARGLIB_NETENCODE" & textToBytesUtf8 + ByteEnv.getEnv envvar >>= \case + Nothing -> dieUserError progName [fmt|could not read args, envvar {envvar} not set|] + Just bytes -> + case Atto.parseOnly (Netencode.netencodeParser <* Atto.endOfInput) bytes of + Left err -> dieEnvironmentProblem progName [fmt|arglib parsing error: {err}|] + Right t -> do + ByteEnv.unsetEnv envvar + pure t |