Add Id module

src/Streamly/Coreutils/Id.hs

@@ -0,0 +1,56 @@
+-- |
+-- Module      : Streamly.Coreutils.Id
+-- Copyright   : (c) 2022 Composewell Technologies
+-- License     : BSD-3-Clause
+-- Maintainer  : streamly@composewell.com
+-- Stability   : experimental
+-- Portability : GHC
+--
+-- Get real and effective user and group IDs.
+
+module Streamly.Coreutils.Id
+    (
+      getRealUserID
+    , getRealGroupID
+    , getEffectiveUserID
+    , getEffectiveGroupID
+    , getGroups
+    , getLoginName
+    , getEffectiveUserName
+    )
+where
+
+import Data.Word (Word32)
+import System.Posix.Types (CGid(CGid), CUid(CUid))
+
+import qualified System.Posix.User as Posix
+
+getRealUserID :: IO Word32
+getRealUserID = do
+    CUid x <- Posix.getRealUserID
+    return x
+
+getRealGroupID :: IO Word32
+getRealGroupID = do
+    CGid x <- Posix.getRealGroupID
+    return x
+
+getEffectiveUserID :: IO Word32
+getEffectiveUserID =  do
+    CUid x <- Posix.getEffectiveUserID
+    return x
+
+getEffectiveGroupID :: IO Word32
+getEffectiveGroupID = do
+    CGid x <- Posix.getEffectiveGroupID
+    return x
+
+getGroups :: IO [Word32]
+getGroups =
+    map (\(CGid x) -> x) <$> Posix.getGroups
+
+getLoginName :: IO String
+getLoginName = Posix.getLoginName
+
+getEffectiveUserName :: IO String
+getEffectiveUserName = Posix.getEffectiveUserName

streamly-coreutils.cabal

@@ -98,6 +98,7 @@ library
     , Streamly.Coreutils.Common
     , Streamly.Coreutils.Cp
     , Streamly.Coreutils.FileTest
+    , Streamly.Coreutils.Id
     , Streamly.Coreutils.ShellWords
     , Streamly.Coreutils.Uniq
     , Streamly.Coreutils.Which