git-annex/Utility/UserInfo.hs
Joey Hess 0a4479b8ec
Avoid backtraces on expected failures when built with ghc 8; only use backtraces for unexpected errors.
ghc 8 added backtraces on uncaught errors. This is great, but git-annex was
using error in many places for a error message targeted at the user, in
some known problem case. A backtrace only confuses such a message, so omit it.

Notably, commands like git annex drop that failed due to eg, numcopies,
used to use error, so had a backtrace.

This commit was sponsored by Ethan Aubin.
2016-11-15 21:29:54 -04:00

63 lines
1.4 KiB
Haskell

{- user info
-
- Copyright 2012 Joey Hess <id@joeyh.name>
-
- License: BSD-2-clause
-}
{-# LANGUAGE CPP #-}
{-# OPTIONS_GHC -fno-warn-tabs #-}
module Utility.UserInfo (
myHomeDir,
myUserName,
myUserGecos,
) where
import Utility.Env
import Utility.Data
import Utility.Exception
import System.PosixCompat
import Control.Applicative
import Prelude
{- Current user's home directory.
-
- getpwent will fail on LDAP or NIS, so use HOME if set. -}
myHomeDir :: IO FilePath
myHomeDir = either giveup return =<< myVal env homeDirectory
where
#ifndef mingw32_HOST_OS
env = ["HOME"]
#else
env = ["USERPROFILE", "HOME"] -- HOME is used in Cygwin
#endif
{- Current user's user name. -}
myUserName :: IO (Either String String)
myUserName = myVal env userName
where
#ifndef mingw32_HOST_OS
env = ["USER", "LOGNAME"]
#else
env = ["USERNAME", "USER", "LOGNAME"]
#endif
myUserGecos :: IO (Maybe String)
-- userGecos crashes on Android and is not available on Windows.
#if defined(__ANDROID__) || defined(mingw32_HOST_OS)
myUserGecos = return Nothing
#else
myUserGecos = eitherToMaybe <$> myVal [] userGecos
#endif
myVal :: [String] -> (UserEntry -> String) -> IO (Either String String)
myVal envvars extract = go envvars
where
#ifndef mingw32_HOST_OS
go [] = Right . extract <$> (getUserEntryForID =<< getEffectiveUserID)
#else
go [] = return $ Left ("environment not set: " ++ show envvars)
#endif
go (v:vs) = maybe (go vs) (return . Right) =<< getEnv v