Lala

Use 8.10.2 in gitlab CI
Add GHC-8.10.2 for alpine 32big
2020-08-27 23:39:47 +02:00 · 2020-08-15 23:54:50 +02:00 · 2020-08-15 23:34:05 +02:00 · 2020-08-14 22:27:05 +02:00 · 2020-08-14 22:07:39 +02:00 · 2020-08-14 21:49:01 +02:00
37 changed files with 2375 additions and 5467 deletions
--- a/.gitignore
+++ b/.gitignore
@@ -12,3 +12,4 @@ tags
 TAGS
 /tmp/
 .entangled
+release/
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -14,6 +14,7 @@ variables:
    - x86_64-linux
  variables:
    OS: "LINUX"
+    BIT: "64"

 .alpine:64bit:
  image: "alpine:edge"
@@ -36,12 +37,14 @@ variables:
    - x86_64-darwin
  variables:
    OS: "DARWIN"
+    BIT: "64"

 .freebsd:
  tags:
    - x86_64-freebsd
  variables:
    OS: "FREEBSD"
+    BIT: "64"

 .root_cleanup:
  after_script:
@@ -66,6 +69,13 @@ variables:
  before_script:
    - ./.gitlab/before_script/linux/install_deps.sh

+.test_ghcup_version:linux32:
+  extends:
+    - .test_ghcup_version
+    - .alpine:32bit
+  before_script:
+    - ./.gitlab/before_script/linux/alpine/install_deps.sh
+
 .test_ghcup_version:darwin:
  extends:
    - .test_ghcup_version
@@ -103,10 +113,17 @@ test:linux:recommended:
 test:linux:latest:
  extends: .test_ghcup_version:linux
  variables:
-    GHC_VERSION: "8.10.1"
+    GHC_VERSION: "8.10.2"
    CABAL_VERSION: "3.2.0.0"
  allow_failure: true

+######## linux 32bit test ########
+
+test:linux:recommended:32bit:
+  extends: .test_ghcup_version:linux32
+  variables:
+    GHC_VERSION: "8.8.4"
+    CABAL_VERSION: "3.2.0.0"

 ######## darwin test ########

@@ -119,7 +136,7 @@ test:mac:recommended:
 test:mac:latest:
  extends: .test_ghcup_version:darwin
  variables:
-    GHC_VERSION: "8.10.1"
+    GHC_VERSION: "8.10.2"
    CABAL_VERSION: "3.2.0.0"
  allow_failure: true

@@ -135,7 +152,7 @@ test:freebsd:recommended:
 test:freebsd:latest:
  extends: .test_ghcup_version:freebsd
  variables:
-    GHC_VERSION: "8.10.1"
+    GHC_VERSION: "8.10.2"
    CABAL_VERSION: "3.2.0.0"
  allow_failure: true

--- a/.gitlab/before_script/linux/alpine/install_deps.sh
+++ b/.gitlab/before_script/linux/alpine/install_deps.sh
@@ -18,10 +18,6 @@ apk add --no-cache \
 	tar \
 	perl

-ln -sf libncurses.so /usr/lib/libtinfo.so
-ln -sf libncursesw.so.6 /usr/lib/libtinfow.so.6
-ln -sf libtinfow.so.6 /usr/lib/libtinfow.so
-
 if [ "${BIT}" = "32" ] ; then
 	curl -sSfL https://downloads.haskell.org/ghcup/i386-linux-ghcup > ./ghcup-bin
 else
@@ -49,5 +45,3 @@ apk add --no-cache \
 	xz-dev \
 	ncurses-static

-ln -sf libncursesw.a /usr/lib/libtinfow.a
-
--- a/.gitlab/script/ghcup_version.sh
+++ b/.gitlab/script/ghcup_version.sh
@@ -11,7 +11,7 @@ ecabal() {
 }

 eghcup() {
-	ghcup -v -c -s file://$(pwd)/ghcup-${JSON_VERSION}.json "$@"
+	ghcup -v -c -s file://$(pwd)/ghcup-${JSON_VERSION}.yaml "$@"
 }

 git describe --always
@@ -22,14 +22,20 @@ ecabal update

 if [ "${OS}" = "DARWIN" ] ; then
 	ecabal build -w ghc-${GHC_VERSION} -ftui
+elif [ "${OS}" = "LINUX" ] ; then
+	if [ "${BIT}" = "32" ] ; then
+		ecabal build -w ghc-${GHC_VERSION} -finternal-downloader -ftui -ftar
+	else
+		ecabal build -w ghc-${GHC_VERSION} -finternal-downloader -ftui
+	fi
 else
 	ecabal build -w ghc-${GHC_VERSION} -finternal-downloader -ftui
 fi

-ecabal haddock
+ecabal haddock -w ghc-${GHC_VERSION} -ftar

-cp "$(ecabal new-exec --enable-tests --verbose=0 --offline sh -- -c 'command -v ghcup')" .
-cp "$(ecabal new-exec --enable-tests --verbose=0 --offline sh -- -c 'command -v ghcup-gen')" .
+cp "$(ecabal new-exec -w ghc-${GHC_VERSION} --enable-tests --verbose=0 --offline sh -- -c 'command -v ghcup')" .
+cp "$(ecabal new-exec -w ghc-${GHC_VERSION} --enable-tests --verbose=0 --offline sh -- -c 'command -v ghcup-gen')" .

 cp ./ghcup "$CI_PROJECT_DIR"/.local/bin/ghcup
 cp ./ghcup-gen "$CI_PROJECT_DIR"/.local/bin/ghcup-gen
@@ -42,7 +48,7 @@ rm -rf "${GHCUP_INSTALL_BASE_PREFIX}"/.ghcup
 ### manual cli based testing


-ghcup-gen check -f ghcup-${JSON_VERSION}.json
+ghcup-gen check -f ghcup-${JSON_VERSION}.yaml

 eghcup --numeric-version

--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,21 @@
 # Revision history for ghcup

+## 0.1.10 -- 2020-08-14
+
+* Show stray Cabals (useful for pre-releases or compiled ones)
+
+## 0.1.9 -- 2020-08-14
+
+* Fix bug when uninstalling all cabal versions
+* Fix bug when setting a non-installed ghc version as current default
+* Use yaml instead of generated json for download info for ease of adding new GHC versions #44
+* Allow pre-release versions of GHC/cabal
+* Add XDG dirs support (set `GHCUP_USE_XDG_DIRS`) wrt #39
+* Allow to specify regex for tarball subdir (e.g. `ghc-.*`)
+* Allow installing arbitrary bindists more seamlessly:
+  - e.g. installing GHC HEAD: `ghcup -n install ghc -u '{"dlHash": "", "dlSubdir": { "RegexDir": "ghc-.*"}, "dlUri": "https://gitlab.haskell.org/api/v4/projects/1/jobs/artifacts/master/raw/ghc-x86_64-fedora27-linux.tar.xz?job=validate-x86_64-linux-fedora27" }' head`
+* Avoid duplicate edits to .bashrc/.zshrc wrt #43
+
 ## 0.1.8 -- 2020-07-21

 * Fix bug in logging thread dying on newlines
--- a/README.md
+++ b/README.md
@@ -13,6 +13,7 @@ Similar in scope to [rustup](https://github.com/rust-lang-nursery/rustup.rs), [p
     * [Manpages](#manpages)
     * [Shell-completion](#shell-completion)
     * [Cross support](#cross-support)
+     * [XDG support](#xdg-support)
   * [Design goals](#design-goals)
   * [How](#how)
   * [Known users](#known-users)
@@ -96,6 +97,16 @@ For distributions with non-standard locations of cross toolchain and
 libraries, this may need some tweaking of `build.mk` or configure args.
 See `ghcup compile ghc --help` for further information.

+### XDG support
+
+To enable XDG style directories, set the environment variable `GHCUP_USE_XDG_DIRS` to anything.
+
+Then you can control the locations via XDG environment variables as such:
+
+* `XDG_DATA_HOME`: GHCs will be unpacked in `ghcup/ghc` subdir
+* `XDG_CACHE_HOME`: logs and download files will be stored in `ghcup` subdir
+* `XDG_BIN_HOME`: binaries end up here (default: `~/.local/bin`)
+
 ## Design goals

 1. simplicity
--- a/RELEASING.md
+++ b/RELEASING.md
@@ -1,19 +1,19 @@
 # RELEASING

-1. update `GHCup.Version` module. `ghcupURL` must only be updated if we change the `_toolRequirements` type or the JSON representation of it. The version of the json represents the change increments. `ghcUpVer` is the current application version.
+1. update `GHCup.Version` module. `ghcupURL` must only be updated if we change the `_toolRequirements` type or the YAML representation of it. The version of the YAML represents the change increments. `ghcUpVer` is the current application version.

 2. Update version in ghcup.cabal

 3. Add ChangeLog entry

-4. Add/fix downloads to `GHCupDownloads` module, then run `ghcup-gen gen` to generate the new json and validate it via `ghcup-gen check`.
+4. Add/fix downloads in `ghcup-<ver>.yaml`, then verify with `ghcup-gen check -f ghcup-<ver>.yaml`

 5. Commit and git push with tag. Wait for tests to succeed and release artifacts to build.

 6. Download release artifacts and upload them `downloads.haskell.org/ghcup`

-7. Add release artifacts to GHCupDownloads (see point 4.)
+7. Add release artifacts to yaml file (see point 4.)

-8. Upload the final `ghcup-<ver>.json` to `webhost.haskell.org/ghcup/data/`.
+8. Upload the final `ghcup-<ver>.yaml` to `webhost.haskell.org/ghcup/data/`.

 9. Update bootstrap-haskell and symlinks on `downloads.haskell.org/ghcup`
--- a/app/ghcup-gen/Main.hs
+++ b/app/ghcup-gen/Main.hs
@@ -10,13 +10,10 @@

 module Main where

-import           GHCup.Data.GHCupInfo
 import           GHCup.Types
 import           GHCup.Types.JSON               ( )
 import           GHCup.Utils.Logger

-import           Data.Aeson                     ( eitherDecode, encode )
-import           Data.Aeson.Encode.Pretty
 #if !MIN_VERSION_base(4,13,0)
 import           Data.Semigroup                 ( (<>) )
 #endif
@@ -27,48 +24,15 @@ import           System.IO                      ( stdout )
 import           Validate

 import qualified Data.ByteString               as B
-import qualified Data.ByteString.Lazy          as L
+import qualified Data.Yaml                     as Y


 data Options = Options
  { optCommand :: Command
  }

-data Command = GenJSON GenJSONOpts
-             | ValidateJSON ValidateJSONOpts
-             | ValidateTarballs ValidateJSONOpts
-
-data Output
-  = FileOutput FilePath -- optsparse-applicative doesn't handle ByteString correctly anyway
-  | StdOutput
-
-fileOutput :: Parser Output
-fileOutput =
-  FileOutput
-    <$> (strOption
-          (long "file" <> short 'f' <> metavar "FILENAME" <> help
-            "Output to a file"
-          )
-        )
-
-stdOutput :: Parser Output
-stdOutput = flag'
-  StdOutput
-  (short 'o' <> long "stdout" <> help "Print to stdout (default)")
-
-outputP :: Parser Output
-outputP = fileOutput <|> stdOutput
-
-
-data GenJSONOpts = GenJSONOpts
-  { output :: Maybe Output
-  , pretty :: Bool
-  }
-
-genJSONOpts :: Parser GenJSONOpts
-genJSONOpts = GenJSONOpts <$> optional outputP <*> switch
-  (short 'p' <> long "pretty" <> help "Make JSON output pretty (human readable)"
-  )
+data Command = ValidateYAML ValidateYAMLOpts
+             | ValidateTarballs ValidateYAMLOpts


 data Input
@@ -92,12 +56,12 @@ stdInput = flag'
 inputP :: Parser Input
 inputP = fileInput <|> stdInput

-data ValidateJSONOpts = ValidateJSONOpts
-  { input :: Maybe Input
+data ValidateYAMLOpts = ValidateYAMLOpts
+  { vInput :: Maybe Input
  }

-validateJSONOpts :: Parser ValidateJSONOpts
-validateJSONOpts = ValidateJSONOpts <$> optional inputP
+validateYAMLOpts :: Parser ValidateYAMLOpts
+validateYAMLOpts = ValidateYAMLOpts <$> optional inputP

 opts :: Parser Options
 opts = Options <$> com
@@ -105,18 +69,10 @@ opts = Options <$> com
 com :: Parser Command
 com = subparser
  (  (command
-       "gen"
-       (   GenJSON
-       <$> (info (genJSONOpts <**> helper)
-                 (progDesc "Generate the json downloads file")
-           )
-       )
-     )
-  <> (command
       "check"
-       (   ValidateJSON
-       <$> (info (validateJSONOpts <**> helper)
-                 (progDesc "Validate the JSON")
+       (   ValidateYAML
+       <$> (info (validateYAMLOpts <**> helper)
+                 (progDesc "Validate the YAML")
           )
       )
     )
@@ -124,7 +80,7 @@ com = subparser
       "check-tarballs"
       (   ValidateTarballs
       <$> (info
-             (validateJSONOpts <**> helper)
+             (validateYAMLOpts <**> helper)
             (progDesc "Validate all tarballs (download and checksum)")
           )
       )
@@ -135,38 +91,27 @@ com = subparser

 main :: IO ()
 main = do
-  customExecParser (prefs showHelpOnError) (info (opts <**> helper) idm)
+  _ <- customExecParser (prefs showHelpOnError) (info (opts <**> helper) idm)
    >>= \Options {..} -> case optCommand of
-          GenJSON gopts -> do
-            let bs True =
-                  encodePretty' (defConfig { confIndent = Spaces 2 }) ghcupInfo
-                bs False = encode ghcupInfo
-            case gopts of
-              GenJSONOpts { output = Nothing, pretty } ->
-                L.hPutStr stdout (bs pretty)
-              GenJSONOpts { output = Just StdOutput, pretty } ->
-                L.hPutStr stdout (bs pretty)
-              GenJSONOpts { output = Just (FileOutput file), pretty } ->
-                L.writeFile file (bs pretty)
-          ValidateJSON vopts -> case vopts of
-            ValidateJSONOpts { input = Nothing } ->
-              L.getContents >>= valAndExit validate
-            ValidateJSONOpts { input = Just StdInput } ->
-              L.getContents >>= valAndExit validate
-            ValidateJSONOpts { input = Just (FileInput file) } ->
-              L.readFile file >>= valAndExit validate
+          ValidateYAML vopts -> case vopts of
+            ValidateYAMLOpts { vInput = Nothing } ->
+              B.getContents >>= valAndExit validate
+            ValidateYAMLOpts { vInput = Just StdInput } ->
+              B.getContents >>= valAndExit validate
+            ValidateYAMLOpts { vInput = Just (FileInput file) } ->
+              B.readFile file >>= valAndExit validate
          ValidateTarballs vopts -> case vopts of
-            ValidateJSONOpts { input = Nothing } ->
-              L.getContents >>= valAndExit validateTarballs
-            ValidateJSONOpts { input = Just StdInput } ->
-              L.getContents >>= valAndExit validateTarballs
-            ValidateJSONOpts { input = Just (FileInput file) } ->
-              L.readFile file >>= valAndExit validateTarballs
+            ValidateYAMLOpts { vInput = Nothing } ->
+              B.getContents >>= valAndExit validateTarballs
+            ValidateYAMLOpts { vInput = Just StdInput } ->
+              B.getContents >>= valAndExit validateTarballs
+            ValidateYAMLOpts { vInput = Just (FileInput file) } ->
+              B.readFile file >>= valAndExit validateTarballs
  pure ()

 where
  valAndExit f contents = do
-    (GHCupInfo _ av) <- case eitherDecode contents of
+    (GHCupInfo _ av) <- case Y.decodeEither' contents of
      Right r -> pure r
      Left  e -> die (color Red $ show e)
    myLoggerT (LoggerConfig True (B.hPut stdout) (\_ -> pure ())) (f av)
--- a/app/ghcup-gen/Validate.hs
+++ b/app/ghcup-gen/Validate.hs
@@ -7,7 +7,10 @@ module Validate where
 import           GHCup
 import           GHCup.Download
 import           GHCup.Types
+import           GHCup.Utils.Dirs
+import           GHCup.Utils.File
 import           GHCup.Utils.Logger
+import           GHCup.Utils.Version.QQ

 import           Control.Exception.Safe
 import           Control.Monad
@@ -88,6 +91,15 @@ validate dls = do
    when ((not $ any (== FreeBSD) pspecs) && arch == A_64) $ lift $ $(logWarn)
      [i|FreeBSD missing for #{t} #{v'} #{arch}|]

+    -- alpine needs to be set explicitly, because
+    -- we cannot assume that "Linux UnknownLinux" runs on Alpine
+    -- (although it could be static)
+    when (not $ any (== Linux Alpine) pspecs) $
+      case t of
+        GHCup -> (lift $ $(logError) [i|Linux Alpine missing for #{t} #{v'} #{arch}|]) >> addError
+        Cabal | v > [vver|2.4.1.0|] -> (lift $ $(logError) [i|Linux Alpine missing for #{t} #{v'} #{arch}|]) >> addError
+        _     -> lift $ $(logWarn) [i|Linux Alpine missing for #{t} #{v'} #{arch}|]
+
  checkUniqueTags tool = do
    let allTags = join $ M.elems $ availableToolVersions dls tool
    let nonUnique =
@@ -111,6 +123,7 @@ validate dls = do
   where
    isUniqueTag Latest         = True
    isUniqueTag Recommended    = True
+    isUniqueTag Prerelease     = False
    isUniqueTag (Base       _) = False
    isUniqueTag (UnknownTag _) = False

@@ -179,7 +192,8 @@ validateTarballs dls = do

 where
  downloadAll dli = do
-    let settings = Settings True False Never Curl False
+    dirs <- liftIO getDirs
+    let settings = Settings True False Never Curl False dirs defExecCb
    let runLogger = myLoggerT LoggerConfig { lcPrintDebug = True
                                           , colorOutter  = B.hPut stderr
                                           , rawOutter    = (\_ -> pure ())
--- a/app/ghcup/BrickMain.hs
+++ b/app/ghcup/BrickMain.hs
@@ -14,8 +14,10 @@ import           GHCup.Types
 import           GHCup.Utils
 import           GHCup.Utils.File
 import           GHCup.Utils.Logger
+import           GHCup.Utils.Prelude

 import           Brick
+import           Brick.BChan
 import           Brick.Widgets.Border
 import           Brick.Widgets.Border.Style
 import           Brick.Widgets.Center
@@ -23,11 +25,14 @@ import           Brick.Widgets.List
 #if !defined(TAR)
 import           Codec.Archive
 #endif
+import           Control.Concurrent
+import           Control.Concurrent.MVar
 import           Control.Exception.Safe
 import           Control.Monad.Logger
 import           Control.Monad.Reader
 import           Control.Monad.Trans.Resource
 import           Data.Bool
+import           Data.ByteString                ( ByteString )
 import           Data.Functor
 import           Data.List
 import           Data.Maybe
@@ -37,22 +42,40 @@ import           Data.String.Interpolate
 import           Data.Vector                    ( Vector )
 import           Data.Versions           hiding ( str )
 import           Haskus.Utils.Variant.Excepts
-import           Prelude                 hiding ( appendFile )
+import           HPath
+import           HPath.IO                hiding ( hideError )
+import           Prelude                 hiding ( abs, appendFile, writeFile )
 import           System.Exit
 import           System.IO.Unsafe
+import           System.Posix.Types
 import           URI.ByteString

 import qualified Data.Text                     as T
 import qualified Graphics.Vty                  as Vty
 import qualified Data.Vector                   as V
+import qualified "unix-bytestring" System.Posix.IO.ByteString
+                                               as SPIB

+data SubProcess = SubProcess {
+    procName :: String
+  , exited   :: Maybe (Either ProcessError ())
+  , procId   :: Maybe ProcessID
+  , logLine  :: Maybe ByteString
+}

 data AppState = AppState {
-    lr :: LR
-  , dls :: GHCupDownloads
+    lr    :: LR
+  , dls   :: GHCupDownloads
  , pfreq :: PlatformRequest
+
+  , mproc :: Maybe SubProcess
 }

+data MyAppEvent = LogLine ByteString
+                | StartProc String
+                | GotProcId ProcessID
+                | EndProc (Either ProcessError ())
+
 type LR = GenericList String Vector ListResult


@@ -68,21 +91,28 @@ keyHandlers =

 ui :: AppState -> Widget String
 ui AppState {..} =
-  ( padBottom Max
-    $ ( withBorderStyle unicode
-      $ borderWithLabel (str "GHCup")
-      $ (center $ renderList renderItem True lr)
-      )
-    )
-    <=> ( withAttr "help"
-        . txtWrap
-        . T.pack
-        . foldr1 (\x y -> x <> "  " <> y)
-        . (++ ["↑↓:Navigation"])
-        $ (fmap (\(c, s, _) -> (c : ':' : s)) keyHandlers)
-        )
+  case mproc of
+    Just _ -> logDialog
+    Nothing ->
+              ( padBottom Max
+                $ ( withBorderStyle unicode
+                  $ borderWithLabel (str "GHCup")
+                  $ (center $ renderList renderItem True lr)
+                  )
+                )
+                <=> ( withAttr "help"
+                    . txtWrap
+                    . T.pack
+                    . foldr1 (\x y -> x <> "  " <> y)
+                    . (++ ["↑↓:Navigation"])
+                    $ (fmap (\(c, s, _) -> (c : ':' : s)) keyHandlers)
+                    )

 where
+  logDialog = case mproc of
+    Nothing -> emptyWidget
+    Just (SubProcess name Nothing _ (Just logLine)) -> centerLayer . txtWrap . decUTF8Safe $ logLine
+    Just (SubProcess name Nothing _ (Just logLine)) -> centerLayer . txtWrap $ ""
  renderItem b ListResult {..} =
    let marks = if
          | lSet       -> (withAttr "set" $ str "✔✔")
@@ -112,6 +142,7 @@ ui AppState {..} =

  printTag Recommended        = withAttr "recommended" $ str "recommended"
  printTag Latest             = withAttr "latest" $ str "latest"
+  printTag Prerelease         = withAttr "prerelease" $ str "prerelease"
  printTag (Base       pvp'') = str ("base-" ++ T.unpack (prettyPVP pvp''))
  printTag (UnknownTag t    ) = str t

@@ -120,7 +151,7 @@ minHSize :: Int -> Widget n -> Widget n
 minHSize s' = hLimit s' . vLimit 1 . (<+> fill ' ')


-app :: App AppState e String
+app :: App AppState MyAppEvent String
 app = App { appDraw         = \st -> [ui st]
          , appHandleEvent  = eventHandler
          , appStartEvent   = return
@@ -137,6 +168,7 @@ defaultAttributes = attrMap
  , ("installed"    , Vty.defAttr `Vty.withForeColor` Vty.green)
  , ("recommended"  , Vty.defAttr `Vty.withForeColor` Vty.green)
  , ("latest"       , Vty.defAttr `Vty.withForeColor` Vty.yellow)
+  , ("prerelease"   , Vty.defAttr `Vty.withForeColor` Vty.red)
  , ("help"         , Vty.defAttr `Vty.withStyle` Vty.italic)
  ]

@@ -150,19 +182,33 @@ dimAttributes = attrMap



-eventHandler :: AppState -> BrickEvent n e -> EventM n (Next AppState)
+eventHandler :: AppState -> BrickEvent n MyAppEvent -> EventM n (Next AppState)
 eventHandler st (VtyEvent (Vty.EvResize _               _)) = continue st
 eventHandler st (VtyEvent (Vty.EvKey    (Vty.KChar 'q') _)) = halt st
 eventHandler st (VtyEvent (Vty.EvKey    Vty.KEsc        _)) = halt st
 eventHandler AppState {..} (VtyEvent (Vty.EvKey (Vty.KUp) _)) =
-  continue (AppState (listMoveUp lr) dls pfreq)
+  continue (AppState (listMoveUp lr) dls pfreq mproc)
 eventHandler AppState {..} (VtyEvent (Vty.EvKey (Vty.KDown) _)) =
-  continue (AppState (listMoveDown lr) dls pfreq)
+  continue (AppState (listMoveDown lr) dls pfreq mproc)
 eventHandler as (VtyEvent (Vty.EvKey (Vty.KChar c) _)) =
  case find (\(c', _, _) -> c' == c) keyHandlers of
    Nothing              -> continue as
    Just (_, _, handler) -> handler as
-eventHandler st _ = continue st
+eventHandler st (AppEvent (StartProc str')) = continue st
+  { mproc = Just SubProcess { procName = str'
+                            , exited   = Nothing
+                            , procId   = Nothing
+                            , logLine  = Nothing
+                            }
+  }
+eventHandler st@AppState { mproc = Just sp } (AppEvent (GotProcId pid)) =
+  continue st { mproc = Just sp { procId = Just pid } }
+eventHandler st@AppState { mproc = Just sp } (AppEvent (EndProc exited)) =
+  continue st { mproc = Just sp { exited = Just exited, procId = Nothing } }
+eventHandler st@AppState { mproc = Just sp } (AppEvent (LogLine bs)) =
+  continue st { mproc = Just sp { logLine = Just bs } }
+eventHandler st (AppEvent _) = error "noes" -- TODO
+eventHandler st _             = continue st


 -- | Suspend the current UI and run an IO action in terminal. If the
@@ -172,20 +218,18 @@ withIOAction :: (AppState -> (Int, ListResult) -> IO (Either String a))
             -> EventM n (Next AppState)
 withIOAction action as = case listSelectedElement (lr as) of
  Nothing      -> continue as
-  Just (ix, e) -> suspendAndResume $ do
-    r <- action as (ix, e)
-    case r of
-      Left  err -> throwIO $ userError err
-      Right _   -> do
-        apps <- (fmap . fmap)
-          (\AppState {..} -> AppState { lr = listMoveTo ix lr, .. })
-          $ getAppState Nothing (pfreq as)
-        case apps of
-          Right nas -> do
-            putStrLn "Press enter to continue"
-            _ <- getLine
-            pure nas
-          Left err -> throwIO $ userError err
+  Just (ix, e) -> do
+    liftIO $ forkIO $ void $ action as (ix, e)
+    continue as
+    -- apps <- (fmap . fmap)
+      -- (\AppState {..} -> AppState { lr = listMoveTo ix lr, .. })
+      -- $ getAppState Nothing (pfreq as)
+    -- case apps of
+      -- Right nas -> do
+        -- putStrLn "Press enter to continue"
+        -- _ <- getLine
+        -- pure nas
+      -- Left err -> throwIO $ userError err


 install' :: AppState -> (Int, ListResult) -> IO (Either String ())
@@ -213,7 +257,9 @@ install' AppState {..} (_, ListResult {..}) = do
            , TagNotFound
            , DigestError
            , DownloadFailed
-            , NoUpdate]
+            , NoUpdate
+            , TarDirDoesNotExist
+            ]

  (run $ do
      case lTool of
@@ -296,14 +342,16 @@ uri' = unsafePerformIO (newIORef Nothing)

 settings' :: IORef Settings
 {-# NOINLINE settings' #-}
-settings' = unsafePerformIO
-  (newIORef Settings { cache      = True
-                     , noVerify   = False
-                     , keepDirs   = Never
-                     , downloader = Curl
-                     , verbose    = False
-                     }
-  )
+settings' = unsafePerformIO $ do
+  dirs <- getDirs
+  newIORef Settings { cache      = True
+                    , noVerify   = False
+                    , keepDirs   = Never
+                    , downloader = Curl
+                    , verbose    = False
+                    , execCb     = (\_ _ _ _ _ -> liftIO $ writeFile [abs|/home/jule/git/ghcup-hs/cb.log|] Nothing "settings'")
+                    , ..
+                    }


 logger' :: IORef LoggerConfig
@@ -317,16 +365,22 @@ logger' = unsafePerformIO


 brickMain :: Settings -> Maybe URI -> LoggerConfig -> GHCupDownloads -> PlatformRequest -> IO ()
-brickMain s muri l av pfreq' = do
+brickMain _ muri _ av pfreq' = do
  writeIORef uri'      muri
-  writeIORef settings' s
+  s <- readIORef settings'
  -- logger interpreter
-  writeIORef logger'   l
+  -- writeIORef logger'   l
+  l <- readIORef logger'
  let runLogger = myLoggerT l

  eApps <- getAppState (Just av) pfreq'
  case eApps of
-    Right as -> defaultMain app (selectLatest as) $> ()
+    Right as -> do
+      eventChan <- newBChan 1000
+      let builder = Vty.mkVty Vty.defaultConfig
+      initialVty <- builder
+      writeIORef settings' s{ execCb = brickExecCb eventChan }
+      customMain initialVty builder (Just eventChan) app (selectLatest as) $> ()
    Left  e  -> do
      runLogger ($(logError) [i|Error building app state: #{show e}|])
      exitWith $ ExitFailure 2
@@ -355,8 +409,25 @@ getAppState mg pfreq' = do
        dls <- maybe (fmap _ghcupDownloads $ liftE $ getDownloadsF (maybe GHCupURL OwnSource muri)) pure mg

        lV <- lift $ listVersions dls Nothing Nothing pfreq'
-        pure $ (AppState (list "Tool versions" (V.fromList lV) 1) dls pfreq')
+        pure $ (AppState (list "Tool versions" (V.fromList lV) 1) dls pfreq' Nothing)

  case r of
    VRight a -> pure $ Right a
    VLeft  e -> pure $ Left [i|#{e}|]
+
+
+brickExecCb :: BChan MyAppEvent -> ExecCb
+brickExecCb chan _ fileFd stdoutRead pState lfile = do
+  liftIO $ writeFile [abs|/home/jule/git/ghcup-hs/cb.log|] Nothing "brickExecCb"
+  writeBChan chan (StartProc . T.unpack . decUTF8Safe $ lfile)
+  readLineTilEOF lineAction stdoutRead
+  takeMVar pState >>= \case
+    PExited e@(Left _) -> writeBChan chan (EndProc e)
+    _ -> error "no"
+ where
+   lineAction bs = do
+     void $ SPIB.fdWrite fileFd (bs <> "\n")
+     error "blah"
+     writeBChan chan (LogLine bs)
+
+
--- a/app/ghcup/Main.hs
+++ b/app/ghcup/Main.hs
@@ -1,6 +1,7 @@
 {-# LANGUAGE CPP               #-}
 {-# LANGUAGE DataKinds         #-}
 {-# LANGUAGE TypeApplications  #-}
+{-# LANGUAGE FlexibleContexts  #-}
 {-# LANGUAGE OverloadedStrings #-}
 {-# LANGUAGE TemplateHaskell   #-}
 {-# LANGUAGE QuasiQuotes       #-}
@@ -403,7 +404,11 @@ installParser =
  installGHCFooter = [s|Discussion:
  Installs the specified GHC version (or a recommended default one) into
  a self-contained "~/.ghcup/ghc/<ghcver>" directory
-  and symlinks the ghc binaries to "~/.ghcup/bin/<binary>-<ghcver>".|]
+  and symlinks the ghc binaries to "~/.ghcup/bin/<binary>-<ghcver>".
+
+Examples:
+  # install GHC head
+  ghcup -n install ghc -u '{"dlHash": "", "dlSubdir": { "RegexDir": "ghc-.*"}, "dlUri": "https://gitlab.haskell.org/api/v4/projects/1/jobs/artifacts/master/raw/ghc-x86_64-fedora27-linux.tar.xz?job=validate-x86_64-linux-fedora27" }' head|]


 installOpts :: Parser InstallOptions
@@ -427,7 +432,7 @@ installOpts =
            <> long "url"
            <> metavar "BINDIST_URL"
            <> help
-                 "Provide DownloadInfo as json string, e.g.: '{ \"dlHash\": \"<sha256 hash>\", \"dlSubdir\": \"ghc-<ver>\", \"dlUri\": \"<uri>\" }'"
+                 "Provide DownloadInfo as json string, e.g.: '{ \"dlHash\": \"<sha256 hash>\", \"dlSubdir\": { \"RegexDir\": \"ghc-.*\"}, \"dlUri\": \"<uri>\" }'"
            )
          )
        )
@@ -818,14 +823,15 @@ bindistParser :: String -> Either String DownloadInfo
 bindistParser = eitherDecode . BLU.fromString


-toSettings :: Options -> Settings
-toSettings Options {..} =
+toSettings :: Options -> IO Settings
+toSettings Options {..} = do
  let cache      = optCache
      noVerify   = optNoVerify
      keepDirs   = optKeepDirs
      downloader = optsDownloader
      verbose    = optVerbose
-  in  Settings { .. }
+  dirs <- getDirs
+  pure $ Settings { execCb     = (\_ _ _ _ _ -> liftIO $ HPath.IO.writeFile [HPath.abs|/home/jule/git/ghcup-hs/cb.log|] Nothing "toSettings"), ..}


 upgradeOptsP :: Parser UpgradeOpts
@@ -901,14 +907,13 @@ Report bugs at <https://gitlab.haskell.org/haskell/ghcup-hs/issues>|]
            (footerDoc (Just $ text main_footer))
      )
    >>= \opt@Options {..} -> do
-          let settings@Settings{..} = toSettings opt
+          settings@Settings{dirs = Dirs{..}, ..} <- toSettings opt

          -- create ~/.ghcup dir
-          ghcdir <- ghcupBaseDir
-          createDirIfMissing newDirPerms ghcdir
+          createDirRecursive newDirPerms baseDir

          -- logger interpreter
-          logfile <- initGHCupFileLogging [rel|ghcup.log|]
+          logfile <- flip runReaderT settings $ initGHCupFileLogging [rel|ghcup.log|]
          let loggerConfig = LoggerConfig
                { lcPrintDebug = optVerbose
                , colorOutter  = B.hPut stderr
@@ -939,6 +944,7 @@ Report bugs at <https://gitlab.haskell.org/haskell/ghcup-hs/issues>|]
                      , TagNotFound
                      , DigestError
                      , DownloadFailed
+                      , TarDirDoesNotExist
                      ]

          let
@@ -954,12 +960,13 @@ Report bugs at <https://gitlab.haskell.org/haskell/ghcup-hs/issues>|]
          let
            runSetCabal =
              runLogger
+                . flip runReaderT settings
                . runE
                  @'[ NotInstalled
                    , TagNotFound
                    ]

-          let runListGHC = runLogger
+          let runListGHC = runLogger . flip runReaderT settings

          let runRm =
                runLogger . flip runReaderT settings . runE @'[NotInstalled]
@@ -984,6 +991,7 @@ Report bugs at <https://gitlab.haskell.org/haskell/ghcup-hs/issues>|]
                      , NotFoundInPATH
                      , PatchFailed
                      , UnknownArchive
+                      , TarDirDoesNotExist
 #if !defined(TAR)
                      , ArchiveResult
 #endif
@@ -1003,6 +1011,7 @@ Report bugs at <https://gitlab.haskell.org/haskell/ghcup-hs/issues>|]
                      , NotInstalled
                      , PatchFailed
                      , UnknownArchive
+                      , TarDirDoesNotExist
 #if !defined(TAR)
                      , ArchiveResult
 #endif
@@ -1052,7 +1061,7 @@ Report bugs at <https://gitlab.haskell.org/haskell/ghcup-hs/issues>|]

          case optCommand of
            Upgrade _ _ -> pure ()
-            _ -> runLogger $ checkForUpdates dls pfreq
+            _ -> runLogger $ flip runReaderT settings $ checkForUpdates dls pfreq



@@ -1079,7 +1088,7 @@ Report bugs at <https://gitlab.haskell.org/haskell/ghcup-hs/issues>|]
                            case keepDirs of
                              Never -> runLogger ($(logError) [i|Build failed with #{e}|])
                              _ -> runLogger ($(logError) [i|Build failed with #{e}
-    Check the logs at ~/.ghcup/logs and the build directory #{tmpdir} for more clues.
+    Check the logs at #{logsDir} and the build directory #{tmpdir} for more clues.
    Make sure to clean up #{tmpdir} afterwards.|])
                            pure $ ExitFailure 3
                          VLeft (V NoDownload) -> do
@@ -1092,7 +1101,7 @@ Report bugs at <https://gitlab.haskell.org/haskell/ghcup-hs/issues>|]
                          VLeft e -> do
                            runLogger $ do
                              $(logError) [i|#{e}|]
-                              $(logError) [i|Also check the logs in ~/.ghcup/logs|]
+                              $(logError) [i|Also check the logs in #{logsDir}|]
                            pure $ ExitFailure 3


@@ -1121,7 +1130,7 @@ Report bugs at <https://gitlab.haskell.org/haskell/ghcup-hs/issues>|]
                        VLeft e -> do
                          runLogger $ do
                            $(logError) [i|#{e}|]
-                            $(logError) [i|Also check the logs in ~/.ghcup/logs|]
+                            $(logError) [i|Also check the logs in #{logsDir}|]
                          pure $ ExitFailure 4

          let setGHC' SetOptions{..} =
@@ -1237,9 +1246,9 @@ Report bugs at <https://gitlab.haskell.org/haskell/ghcup-hs/issues>|]
                      VLeft (V (BuildFailed tmpdir e)) -> do
                        case keepDirs of
                          Never -> runLogger ($(logError) [i|Build failed with #{e}
-Check the logs at ~/.ghcup/logs|])
+Check the logs at #{logsDir}|])
                          _ -> runLogger ($(logError) [i|Build failed with #{e}
-Check the logs at ~/.ghcup/logs and the build directory #{tmpdir} for more clues.
+Check the logs at #{logsDir} and the build directory #{tmpdir} for more clues.
 Make sure to clean up #{tmpdir} afterwards.|])
                        pure $ ExitFailure 9
                      VLeft e -> do
@@ -1261,7 +1270,7 @@ Make sure to clean up #{tmpdir} afterwards.|])
                        case keepDirs of
                          Never -> runLogger ($(logError) [i|Build failed with #{e}|])
                          _ -> runLogger ($(logError) [i|Build failed with #{e}
-Check the logs at ~/.ghcup/logs and the build directory #{tmpdir} for more clues.
+Check the logs at #{logsDir} and the build directory #{tmpdir} for more clues.
 Make sure to clean up #{tmpdir} afterwards.|])
                        pure $ ExitFailure 10
                      VLeft e -> do
@@ -1275,9 +1284,7 @@ Make sure to clean up #{tmpdir} afterwards.|])
                  p   <- parseAbs . E.encodeUtf8 . T.pack $ efp
                  pure $ Just p
                (UpgradeAt p)   -> pure $ Just p
-                UpgradeGHCupDir -> do
-                  bdir <- liftIO $ ghcupBinDir
-                  pure (Just (bdir </> [rel|ghcup|]))
+                UpgradeGHCupDir -> pure (Just (binDir </> [rel|ghcup|]))

              (runUpgrade $ (liftE $ upgradeGHCup dls target force pfreq)) >>= \case
                VRight v' -> do
@@ -1422,13 +1429,14 @@ printListResult raw lr = do
 where
  printTag Recommended        = color' Green "recommended"
  printTag Latest             = color' Yellow "latest"
+  printTag Prerelease         = color' Red "prerelease"
  printTag (Base pvp'') = "base-" ++ T.unpack (prettyPVP pvp'')
  printTag (UnknownTag t    ) = t
  color' = case raw of
    True  -> flip const
    False -> color

-checkForUpdates :: (MonadCatch m, MonadLogger m, MonadThrow m, MonadIO m, MonadFail m, MonadLogger m)
+checkForUpdates :: (MonadReader Settings m, MonadCatch m, MonadLogger m, MonadThrow m, MonadIO m, MonadFail m, MonadLogger m)
                => GHCupDownloads
                -> PlatformRequest
                -> m ()
--- a/78
+++ b/78
@@ -4,6 +4,17 @@
 (

 : "${GHCUP_INSTALL_BASE_PREFIX:=$HOME}"
+
+export GHCUP_USE_XDG_DIRS
+
+if [ -n "${GHCUP_USE_XDG_DIRS}" ] ; then
+	GHCUP_DIR=${XDG_DATA_HOME:=$HOME/.local}/ghcup
+	GHCUP_BIN=${XDG_BIN_HOME:=$HOME/.local/bin}
+else
+	GHCUP_DIR=${GHCUP_INSTALL_BASE_PREFIX}/.ghcup
+	GHCUP_BIN=${GHCUP_INSTALL_BASE_PREFIX}/.ghcup/bin
+fi
+
 : "${BOOTSTRAP_HASKELL_GHC_VERSION:=recommended}"
 : "${BOOTSTRAP_HASKELL_CABAL_VERSION:=recommended}"

@@ -29,10 +40,26 @@ _eghcup() {
    fi
 }

+_done() {
+	echo
+    echo "All done!"
+	echo
+	echo "To start a simple repl, run:"
+	echo "  ghci"
+	echo
+	echo "To start a new haskell project in the current directory, run:"
+	echo "  cabal init --interactive"
+	echo
+	echo "To install other GHC versions, run:"
+	echo "  ghcup tui"
+
+	exit 0
+}
+
 download_ghcup() {
 	_plat="$(uname -s)"
 	_arch=$(uname -m)
-	_ghver="0.1.8"
+	_ghver="0.1.10"
 	_base_url="https://downloads.haskell.org/~ghcup"

    case "${_plat}" in
@@ -83,15 +110,15 @@ download_ghcup() {
 			;;
    esac

-	edo curl -Lf "${_url}" > "${GHCUP_INSTALL_BASE_PREFIX}"/.ghcup/bin/ghcup
+	edo curl -Lf "${_url}" > "${GHCUP_BIN}"/ghcup

-    edo chmod +x "${GHCUP_INSTALL_BASE_PREFIX}"/.ghcup/bin/ghcup
+    edo chmod +x "${GHCUP_BIN}"/ghcup

-	cat <<-EOF > "${GHCUP_INSTALL_BASE_PREFIX}"/.ghcup/env || die "Failed to create env file"
-		export PATH="\$HOME/.cabal/bin:\${GHCUP_INSTALL_BASE_PREFIX:=\$HOME}/.ghcup/bin:\$PATH"
+	cat <<-EOF > "${GHCUP_DIR}"/env || die "Failed to create env file"
+		export PATH="\$HOME/.cabal/bin:${GHCUP_BIN}:\$PATH"
 		EOF
 	# shellcheck disable=SC1090
-    edo . "${GHCUP_INSTALL_BASE_PREFIX}"/.ghcup/env
+    edo . "${GHCUP_DIR}"/env
    eghcup upgrade

 	unset _plat _arch _url _ghver _base_url
@@ -102,12 +129,19 @@ echo
 echo "Welcome to Haskell!"
 echo
 echo "This script will download and install the following binaries:"
-echo "  * ghcup - The Haskell toolchain installer (for managing GHC/cabal versions)"
+echo "  * ghcup - The Haskell toolchain installer"
+echo "            (for managing GHC/cabal versions)"
 echo "  * ghc   - The Glasgow Haskell Compiler"
 echo "  * cabal - The Cabal build tool"
 echo
-echo "ghcup installs only into the following directory, which can be removed anytime:"
-echo "  $GHCUP_INSTALL_BASE_PREFIX/.ghcup"
+if [ -z "${GHCUP_USE_XDG_DIRS}" ] ; then
+	echo "ghcup installs only into the following directory,"
+    echo "which can be removed anytime:"
+	echo "  $GHCUP_INSTALL_BASE_PREFIX/.ghcup"
+else
+	echo "ghcup installs into XDG directories as long as"
+    echo "'GHCUP_USE_XDG_DIRS' is set."
+fi
 echo

 if [ -z "${BOOTSTRAP_HASKELL_NONINTERACTIVE}" ] ; then
@@ -119,7 +153,7 @@ if [ -z "${BOOTSTRAP_HASKELL_NONINTERACTIVE}" ] ; then
    read -r answer </dev/tty
 fi

-edo mkdir -p "${GHCUP_INSTALL_BASE_PREFIX}"/.ghcup/bin
+edo mkdir -p "${GHCUP_BIN}"

 if command -V "ghcup" >/dev/null 2>&1 ; then
    if [ -z "${BOOTSTRAP_HASKELL_NO_UPGRADE}" ] ; then
@@ -156,7 +190,7 @@ printf "\\033[0;35m%s\\033[0m\\n" ""

 if [ -z "${BOOTSTRAP_HASKELL_NONINTERACTIVE}" ] ; then
    echo "In order to run ghc and cabal, you need to adjust your PATH variable."
-    echo "You may want to source '$GHCUP_INSTALL_BASE_PREFIX/.ghcup/env' in your shell"
+    echo "You may want to source '$GHCUP_DIR/env' in your shell"
    echo "configuration to do so (e.g. ~/.bashrc)."

 	case $SHELL in
@@ -174,13 +208,13 @@ if [ -z "${BOOTSTRAP_HASKELL_NONINTERACTIVE}" ] ; then
 				GHCUP_PROFILE_FILE="$HOME/.zshrc"
 				MY_SHELL="zsh"
 			else
-				exit 0
+			    _done
 			fi
 			;;
 		*/fish) # login shell is fish
 			GHCUP_PROFILE_FILE="$HOME/.config/fish/config.fish"
 			MY_SHELL="fish" ;;
-		*) exit 0 ;;
+		*) _done ;;
 	esac


@@ -198,18 +232,24 @@ if [ -z "${BOOTSTRAP_HASKELL_NONINTERACTIVE}" ] ; then
 				case $MY_SHELL in
 					"") break ;;
 					fish)
-						echo "set -q GHCUP_INSTALL_BASE_PREFIX[1]; or set GHCUP_INSTALL_BASE_PREFIX \$HOME" >> "${GHCUP_PROFILE_FILE}"
-						echo "test -f \$GHCUP_INSTALL_BASE_PREFIX/.ghcup/env ; and set -gx PATH \$HOME/.cabal/bin \$GHCUP_INSTALL_BASE_PREFIX/.ghcup/bin \$PATH" >> "${GHCUP_PROFILE_FILE}"
+						if ! grep -q "ghcup-env" "${GHCUP_PROFILE_FILE}" ; then
+							echo "# ghcup-env" >> "${GHCUP_PROFILE_FILE}"
+							echo "set -q GHCUP_INSTALL_BASE_PREFIX[1]; or set GHCUP_INSTALL_BASE_PREFIX \$HOME" >> "${GHCUP_PROFILE_FILE}"
+							echo "test -f $GHCUP_DIR/env ; and set -gx PATH \$HOME/.cabal/bin $GHCUP_BIN/bin \$PATH" >> "${GHCUP_PROFILE_FILE}"
+						fi
 						break ;;
 					*)
-						echo "[ -f \"\${GHCUP_INSTALL_BASE_PREFIX:=\$HOME}/.ghcup/env\" ] && source \"\${GHCUP_INSTALL_BASE_PREFIX:=\$HOME}/.ghcup/env\"" >> "${GHCUP_PROFILE_FILE}"
+						if ! grep -q "ghcup-env" "${GHCUP_PROFILE_FILE}" ; then
+							echo "[ -f \"${GHCUP_DIR}/env\" ] && source \"${GHCUP_DIR}/env\" # ghcup-env" >> "${GHCUP_PROFILE_FILE}"
+						fi
 						break ;;
 				esac
                printf "\\033[0;35m%s\\033[0m\\n" "OK! ${GHCUP_PROFILE_FILE} has been modified. Restart your terminal for the changes to take effect,"
-                printf "\\033[0;35m%s\\033[0m\\n" "or type \"source ${GHCUP_INSTALL_BASE_PREFIX}/.ghcup/env\" to apply them in your current terminal session."
-                exit 0;;
+                printf "\\033[0;35m%s\\033[0m\\n" "or type \"source ${GHCUP_DIR}/env\" to apply them in your current terminal session."
+				_done
+                ;;
            [Nn]*)
-                exit 0;;
+                _done ;;
            *)
                echo "Please type YES or NO and press enter.";;
        esac
--- a/cabal.project
+++ b/cabal.project
@@ -19,6 +19,6 @@ package ghcup
 constraints: http-io-streams -brotli

 package libarchive
-  flags: static
+  flags: +static

-allow-newer: base ghc-prim template-haskell
+allow-newer: base, ghc-prim, template-haskell
--- a/ghcup-0.0.2.json
+++ b/ghcup-0.0.2.json
--- a/ghcup-0.0.2.yaml
+++ b/ghcup-0.0.2.yaml
--- a/ghcup.cabal
+++ b/ghcup.cabal
@@ -1,6 +1,6 @@
 cabal-version:      3.0
 name:               ghcup
-version:            0.1.8
+version:            0.1.10
 synopsis:           ghc toolchain installer as an exe/library
 description:
  A rewrite of the shell script ghcup, for providing
@@ -112,7 +112,7 @@ common io-streams
  build-depends: io-streams >=1.5

 common libarchive
-  build-depends: libarchive >= 2.2.5.2
+  build-depends: libarchive >= 2.2.5.0

 common lzma
  build-depends: lzma >=0.0.0.3
@@ -153,6 +153,9 @@ common safe
 common safe-exceptions
  build-depends: safe-exceptions >=0.1

+common split
+  build-depends: split >=0.2.3.4
+
 common streamly
  build-depends: streamly >=0.7.1

@@ -219,6 +222,9 @@ common vty
 common word8
  build-depends: word8 >=0.1.3

+common yaml
+  build-depends: yaml >=0.11.4.0
+
 common zlib
  build-depends: zlib >=0.6.2.1

@@ -273,6 +279,7 @@ library
    , resourcet
    , safe
    , safe-exceptions
+    , split
    , streamly
    , streamly-posix
    , streamly-bytestring
@@ -291,13 +298,11 @@ library
    , vector
    , versions
    , word8
+    , yaml
    , zlib

  exposed-modules:
    GHCup
-    GHCup.Data.GHCupDownloads
-    GHCup.Data.GHCupInfo
-    GHCup.Data.ToolRequirements
    GHCup.Download
    GHCup.Download.Utils
    GHCup.Errors
@@ -359,6 +364,7 @@ executable ghcup
    , table-layout
    , template-haskell
    , text
+    , unix-bytestring
    , uri-bytestring
    , utf8-string
    , versions
@@ -413,6 +419,7 @@ executable ghcup-gen
    , uri-bytestring
    , utf8-string
    , versions
+    , yaml

  --
  main-is:          Main.hs
--- a/lib/GHCup.hs
+++ b/lib/GHCup.hs
@@ -15,7 +15,7 @@
 Module      : GHCup
 Description : GHCup installation functions
 Copyright   : (c) Julian Ospald, 2020
-License     : GPL-3
+License     : LGPL-3.0
 Maintainer  : hasufell@hasufell.de
 Stability   : experimental
 Portability : POSIX
@@ -112,6 +112,7 @@ installGHCBindist :: ( MonadFail m
                        , NoDownload
                        , NotInstalled
                        , UnknownArchive
+                        , TarDirDoesNotExist
 #if !defined(TAR)
                        , ArchiveResult
 #endif
@@ -121,7 +122,7 @@ installGHCBindist :: ( MonadFail m
 installGHCBindist dlinfo ver (PlatformRequest {..}) = do
  let tver = (mkTVer ver)
  lift $ $(logDebug) [i|Requested to install GHC with #{ver}|]
-  whenM (liftIO $ ghcInstalled tver)
+  whenM (lift $ ghcInstalled tver)
    $ (throwE $ AlreadyInstalled GHC ver)

  -- download (or use cached version)
@@ -133,10 +134,10 @@ installGHCBindist dlinfo ver (PlatformRequest {..}) = do
  void $ liftIO $ darwinNotarization _rPlatform tmpUnpack

  -- prepare paths
-  ghcdir <- liftIO $ ghcupGHCDir tver
+  ghcdir <- lift $ ghcupGHCDir tver

  -- the subdir of the archive where we do the work
-  let workdir = maybe tmpUnpack (tmpUnpack </>) (view dlSubdir dlinfo)
+  workdir <- maybe (pure tmpUnpack) (liftE . intoSubdir tmpUnpack) (view dlSubdir dlinfo)

  liftE $ runBuildAction tmpUnpack (Just ghcdir) (installGHC' workdir ghcdir)

@@ -153,7 +154,6 @@ installGHCBindist dlinfo ver (PlatformRequest {..}) = do
    lEM $ execLogged "./configure"
                              False
                              (["--prefix=" <> toFilePath inst] ++ alpineArgs)
-                              [rel|ghc-configure|]
                              (Just path)
                              Nothing
    lEM $ make ["install"] (Just path)
@@ -189,6 +189,7 @@ installGHCBin :: ( MonadFail m
                    , NoDownload
                    , NotInstalled
                    , UnknownArchive
+                    , TarDirDoesNotExist
 #if !defined(TAR)
                    , ArchiveResult
 #endif
@@ -221,6 +222,7 @@ installCabalBindist :: ( MonadMask m
                          , NoDownload
                          , NotInstalled
                          , UnknownArchive
+                          , TarDirDoesNotExist
 #if !defined(TAR)
                          , ArchiveResult
 #endif
@@ -230,14 +232,14 @@ installCabalBindist :: ( MonadMask m
 installCabalBindist dlinfo ver (PlatformRequest {..}) = do
  lift $ $(logDebug) [i|Requested to install cabal version #{ver}|]

-  bindir <- liftIO ghcupBinDir
+  Settings {dirs = Dirs {..}} <- lift ask

  whenM
-      (liftIO $ cabalInstalled ver >>= \a ->
+      (lift (cabalInstalled ver) >>= \a -> liftIO $
        handleIO (\_ -> pure False)
          $ fmap (\x -> a && isSymbolicLink x)
          -- ignore when the installation is a legacy cabal (binary, not symlink)
-          $ getSymbolicLinkStatus (toFilePath (bindir </> [rel|cabal|]))
+          $ getSymbolicLinkStatus (toFilePath (binDir </> [rel|cabal|]))
      )
    $ (throwE $ AlreadyInstalled Cabal ver)

@@ -250,12 +252,12 @@ installCabalBindist dlinfo ver (PlatformRequest {..}) = do
  void $ liftIO $ darwinNotarization _rPlatform tmpUnpack

  -- the subdir of the archive where we do the work
-  let workdir = maybe tmpUnpack (tmpUnpack </>) (view dlSubdir dlinfo)
+  workdir <- maybe (pure tmpUnpack) (liftE . intoSubdir tmpUnpack) (view dlSubdir dlinfo)

-  liftE $ installCabal' workdir bindir
+  liftE $ installCabal' workdir binDir

  -- create symlink if this is the latest version
-  cVers <- liftIO $ fmap rights $ getInstalledCabals
+  cVers <- lift $ fmap rights $ getInstalledCabals
  let lInstCabal = headMay . reverse . sort $ cVers
  when (maybe True (ver >=) lInstCabal) $ liftE $ setCabal ver

@@ -270,12 +272,14 @@ installCabalBindist dlinfo ver (PlatformRequest {..}) = do
  installCabal' path inst = do
    lift $ $(logInfo) "Installing cabal"
    let cabalFile = [rel|cabal|]
-    liftIO $ createDirIfMissing newDirPerms inst
+    liftIO $ createDirRecursive newDirPerms inst
    destFileName <- lift $ parseRel (toFilePath cabalFile <> "-" <> verToBS ver)
+    let destPath = inst </> destFileName
    handleIO (throwE . CopyError . show) $ liftIO $ copyFile
      (path </> cabalFile)
-      (inst </> destFileName)
+      (destPath)
      Overwrite
+    lift $ chmod_777 destPath


 -- | Installs cabal into @~\/.ghcup\/bin/cabal-\<ver\>@ and
@@ -300,6 +304,7 @@ installCabalBin :: ( MonadMask m
                      , NoDownload
                      , NotInstalled
                      , UnknownArchive
+                      , TarDirDoesNotExist
 #if !defined(TAR)
                      , ArchiveResult
 #endif
@@ -328,17 +333,25 @@ installCabalBin bDls ver pfreq = do
 --
 -- Additionally creates a @~\/.ghcup\/share -> ~\/.ghcup\/ghc\/\<ver\>\/share symlink@
 -- for 'SetGHCOnly' constructor.
-setGHC :: (MonadLogger m, MonadThrow m, MonadFail m, MonadIO m)
+setGHC :: ( MonadReader Settings m
+          , MonadLogger m
+          , MonadThrow m
+          , MonadFail m
+          , MonadIO m
+          , MonadCatch m
+          )
       => GHCTargetVersion
       -> SetGHC
       -> Excepts '[NotInstalled] m GHCTargetVersion
 setGHC ver sghc = do
  let verBS = verToBS (_tvVersion ver)
-  ghcdir <- liftIO $ ghcupGHCDir ver
+  ghcdir                        <- lift $ ghcupGHCDir ver
+
+  whenM (lift $ fmap not $ ghcInstalled ver) (throwE (NotInstalled GHC (ver ^. tvVersion % to prettyVer)))

  -- symlink destination
-  bindir <- liftIO $ ghcupBinDir
-  liftIO $ hideError AlreadyExists $ createDirRecursive newDirPerms bindir
+  Settings { dirs = Dirs {..} } <- lift ask
+  liftIO $ hideError AlreadyExists $ createDirRecursive newDirPerms binDir

  -- first delete the old symlinks (this fixes compatibility issues
  -- with old ghcup)
@@ -350,19 +363,26 @@ setGHC ver sghc = do
  -- for ghc tools (ghc, ghci, haddock, ...)
  verfiles <- ghcToolFiles ver
  forM_ verfiles $ \file -> do
-    targetFile <- case sghc of
-      SetGHCOnly -> pure file
+    mTargetFile <- case sghc of
+      SetGHCOnly -> pure $ Just file
      SetGHC_XY  -> do
-        major' <- (\(mj, mi) -> E.encodeUtf8 $ intToText mj <> "." <> intToText mi)
-                     <$> getMajorMinorV (_tvVersion ver)
-        parseRel (toFilePath file <> B.singleton _hyphen <> major')
-      SetGHC_XYZ -> parseRel (toFilePath file <> B.singleton _hyphen <> verBS)
+        v' <-
+          handle
+            (\(e :: ParseError) -> lift $ $(logWarn) [i|#{e}|] >> pure Nothing)
+          $ fmap Just
+          $ getMajorMinorV (_tvVersion ver)
+        forM v' $ \(mj, mi) ->
+          let major' = E.encodeUtf8 $ intToText mj <> "." <> intToText mi
+          in  parseRel (toFilePath file <> B.singleton _hyphen <> major')
+      SetGHC_XYZ ->
+        fmap Just $ parseRel (toFilePath file <> B.singleton _hyphen <> verBS)

    -- create symlink
-    let fullF = bindir </> targetFile
-    let destL = ghcLinkDestination (toFilePath file) ver
-    lift $ $(logDebug) [i|ln -s #{destL} #{toFilePath fullF}|]
-    liftIO $ createSymlink fullF destL
+    forM mTargetFile $ \targetFile -> do
+      let fullF = binDir </> targetFile
+      destL <- lift $ ghcLinkDestination (toFilePath file) ver
+      lift $ $(logDebug) [i|ln -s #{destL} #{toFilePath fullF}|]
+      liftIO $ createSymlink fullF destL

  -- create symlink for share dir
  when (isNothing . _tvTarget $ ver) $ lift $ symlinkShareDir ghcdir verBS
@@ -371,12 +391,13 @@ setGHC ver sghc = do

 where

-  symlinkShareDir :: (MonadIO m, MonadLogger m)
+  symlinkShareDir :: (MonadReader Settings m, MonadIO m, MonadLogger m)
                  => Path Abs
                  -> ByteString
                  -> m ()
  symlinkShareDir ghcdir verBS = do
-    destdir <- liftIO $ ghcupBaseDir
+    Settings { dirs = Dirs {..} } <- ask
+    let destdir = baseDir
    case sghc of
      SetGHCOnly -> do
        let sharedir     = [rel|share|]
@@ -393,7 +414,7 @@ setGHC ver sghc = do


 -- | Set the @~\/.ghcup\/bin\/cabal@ symlink.
-setCabal :: (MonadLogger m, MonadThrow m, MonadFail m, MonadIO m)
+setCabal :: (MonadReader Settings m, MonadLogger m, MonadThrow m, MonadFail m, MonadIO m)
         => Version
         -> Excepts '[NotInstalled] m ()
 setCabal ver = do
@@ -401,14 +422,14 @@ setCabal ver = do
  targetFile <- parseRel ("cabal-" <> verBS)

  -- symlink destination
-  bindir     <- liftIO $ ghcupBinDir
-  liftIO $ hideError AlreadyExists $ createDirRecursive newDirPerms bindir
+  Settings {dirs = Dirs {..}} <- lift ask
+  liftIO $ hideError AlreadyExists $ createDirRecursive newDirPerms binDir

-  whenM (liftIO $ fmap not $ doesFileExist (bindir </> targetFile))
+  whenM (liftIO $ fmap not $ doesFileExist (binDir </> targetFile))
    $ throwE
    $ NotInstalled Cabal (prettyVer ver)

-  let cabalbin = bindir </> [rel|cabal|]
+  let cabalbin = binDir </> [rel|cabal|]

  -- delete old file (may be binary or symlink)
  lift $ $(logDebug) [i|rm -f #{toFilePath cabalbin}|]
@@ -467,6 +488,7 @@ listVersions :: ( MonadCatch m
                , MonadThrow m
                , MonadLogger m
                , MonadIO m
+                , MonadReader Settings m
                )
             => GHCupDownloads
             -> Maybe Tool
@@ -478,13 +500,16 @@ listVersions av lt criteria pfreq = do
    Just t -> do
      -- get versions from GHCupDownloads
      let avTools = availableToolVersions av t
-      lr <- filter' <$> forM (Map.toList avTools) (liftIO . toListResult t)
+      lr <- filter' <$> forM (Map.toList avTools) (toListResult t)

      case t of
        -- append stray GHCs
        GHC -> do
          slr <- strayGHCs avTools
          pure $ (sort (slr ++ lr))
+        Cabal -> do
+          slr <- strayCabals avTools
+          pure $ (sort (slr ++ lr))
        _ -> pure lr
    Nothing -> do
      ghcvers   <- listVersions av (Just GHC) criteria pfreq
@@ -493,7 +518,7 @@ listVersions av lt criteria pfreq = do
      pure (ghcvers <> cabalvers <> ghcupvers)

 where
-  strayGHCs :: (MonadThrow m, MonadLogger m, MonadIO m)
+  strayGHCs :: (MonadReader Settings m, MonadThrow m, MonadLogger m, MonadIO m)
            => Map.Map Version [Tag]
            -> m [ListResult]
  strayGHCs avTools = do
@@ -504,7 +529,7 @@ listVersions av lt criteria pfreq = do
          Just _  -> pure Nothing
          Nothing -> do
            lSet    <- fmap (maybe False (\(GHCTargetVersion _ v ) -> v == _tvVersion)) $ ghcSet Nothing
-            fromSrc <- liftIO $ ghcSrcInstalled tver
+            fromSrc <- ghcSrcInstalled tver
            pure $ Just $ ListResult
              { lTool      = GHC
              , lVer       = _tvVersion
@@ -517,7 +542,7 @@ listVersions av lt criteria pfreq = do
              }
      Right tver@GHCTargetVersion{ .. } -> do
        lSet    <- fmap (maybe False (\(GHCTargetVersion _ v ) -> v == _tvVersion)) $ ghcSet _tvTarget
-        fromSrc <- liftIO $ ghcSrcInstalled tver
+        fromSrc <- ghcSrcInstalled tver
        pure $ Just $ ListResult
          { lTool      = GHC
          , lVer       = _tvVersion
@@ -533,8 +558,35 @@ listVersions av lt criteria pfreq = do
          [i|Could not parse version of stray directory #{toFilePath e}|]
        pure Nothing

+  strayCabals :: (MonadReader Settings m, MonadCatch m, MonadThrow m, MonadLogger m, MonadIO m)
+            => Map.Map Version [Tag]
+            -> m [ListResult]
+  strayCabals avTools = do
+    cabals <- getInstalledCabals
+    fmap catMaybes $ forM cabals $ \case
+      Right ver ->
+        case Map.lookup ver avTools of
+          Just _  -> pure Nothing
+          Nothing -> do
+            lSet    <- fmap (maybe False (== ver)) $ cabalSet
+            pure $ Just $ ListResult
+              { lTool      = Cabal
+              , lVer       = ver
+              , lCross     = Nothing
+              , lTag       = []
+              , lInstalled = True
+              , lStray     = maybe True (const False) (Map.lookup ver avTools)
+              , lNoBindist = False
+              , fromSrc    = False -- actually, we don't know :>
+              , ..
+              }
+      Left e -> do
+        $(logWarn)
+          [i|Could not parse version of stray directory #{toFilePath e}|]
+        pure Nothing
+
  -- NOTE: this are not cross ones, because no bindists
-  toListResult :: Tool -> (Version, [Tag]) -> IO ListResult
+  toListResult :: (MonadReader Settings m, MonadIO m, MonadCatch m) => Tool -> (Version, [Tag]) -> m ListResult
  toListResult t (v, tags) = case t of
    GHC -> do
      let lNoBindist = isLeft $ getDownloadInfo GHC v pfreq av
@@ -587,64 +639,73 @@ listVersions av lt criteria pfreq = do
 -- This may leave GHCup without a "set" version.
 -- Will try to fix the ghc-x.y symlink after removal (e.g. to an
 -- older version).
-rmGHCVer :: (MonadThrow m, MonadLogger m, MonadIO m, MonadFail m)
+rmGHCVer :: ( MonadReader Settings m
+            , MonadThrow m
+            , MonadLogger m
+            , MonadIO m
+            , MonadFail m
+            , MonadCatch m
+            )
         => GHCTargetVersion
         -> Excepts '[NotInstalled] m ()
 rmGHCVer ver = do
-  isSetGHC <- fmap (maybe False (== ver)) $ ghcSet (_tvTarget ver)
-  dir      <- liftIO $ ghcupGHCDir ver
-  let d' = toFilePath dir
-  exists <- liftIO $ doesDirectoryExist dir
+  isSetGHC <- lift $ fmap (maybe False (== ver)) $ ghcSet (_tvTarget ver)

+  whenM (lift $ fmap not $ ghcInstalled ver) (throwE (NotInstalled GHC (ver ^. tvVersion % to prettyVer)))
+  dir <- lift $ ghcupGHCDir ver

-  if exists
-    then do
-      -- this isn't atomic, order matters
-      when isSetGHC $ do
-        lift $ $(logInfo) [i|Removing ghc symlinks|]
-        liftE $ rmPlain (_tvTarget ver)
+  -- this isn't atomic, order matters
+  when isSetGHC $ do
+    lift $ $(logInfo) [i|Removing ghc symlinks|]
+    liftE $ rmPlain (_tvTarget ver)

-      lift $ $(logInfo) [i|Removing directory recursively: #{d'}|]
-      liftIO $ deleteDirRecursive dir
+  lift $ $(logInfo) [i|Removing directory recursively: #{toFilePath dir}|]
+  liftIO $ deleteDirRecursive dir

-      lift $ $(logInfo) [i|Removing ghc-x.y.z symlinks|]
-      lift $ rmMinorSymlinks ver
+  lift $ $(logInfo) [i|Removing ghc-x.y.z symlinks|]
+  lift $ rmMinorSymlinks ver

-      lift $ $(logInfo) [i|Removing/rewiring ghc-x.y symlinks|]
-      -- first remove
-      lift $ rmMajorSymlinks ver
-      -- then fix them (e.g. with an earlier version)
-      (mj, mi) <- getMajorMinorV (_tvVersion ver)
-      getGHCForMajor mj mi (_tvTarget ver) >>= mapM_ (\v -> liftE $ setGHC v SetGHC_XY)
+  lift $ $(logInfo) [i|Removing/rewiring ghc-x.y symlinks|]
+  -- first remove
+  handle (\(_ :: ParseError) -> pure ()) $ lift $ rmMajorSymlinks ver
+  -- then fix them (e.g. with an earlier version)
+  v' <-
+    handle
+      (\(e :: ParseError) -> lift $ $(logWarn) [i|#{e}|] >> pure Nothing)
+    $ fmap Just
+    $ getMajorMinorV (_tvVersion ver)
+  forM_ v' $ \(mj, mi) -> lift (getGHCForMajor mj mi (_tvTarget ver))
+    >>= mapM_ (\v -> liftE $ setGHC v SetGHC_XY)

-      liftIO
-        $   ghcupBaseDir
-        >>= hideError doesNotExistErrorType
-        .   deleteFile
-        .   (</> [rel|share|])
-    else throwE (NotInstalled GHC (ver ^. tvVersion % to prettyVer))
+  Settings { dirs = Dirs {..} } <- lift ask
+
+  liftIO
+    $ hideError doesNotExistErrorType
+    $ deleteFile
+    $ (baseDir </> [rel|share|])


 -- | Delete a cabal version. Will try to fix the @cabal@ symlink
 -- after removal (e.g. setting it to an older version).
-rmCabalVer :: (MonadThrow m, MonadLogger m, MonadIO m, MonadFail m)
+rmCabalVer :: (MonadReader Settings m, MonadThrow m, MonadLogger m, MonadIO m, MonadFail m, MonadCatch m)
           => Version
           -> Excepts '[NotInstalled] m ()
 rmCabalVer ver = do
-  whenM (fmap not $ liftIO $ cabalInstalled ver) $ throwE (NotInstalled GHC (prettyVer ver))
+  whenM (lift $ fmap not $ cabalInstalled ver) $ throwE (NotInstalled Cabal (prettyVer ver))

-  cSet      <- liftIO cabalSet
+  cSet      <- lift $ cabalSet
+
+  Settings {dirs = Dirs {..}} <- lift ask

-  bindir    <- liftIO ghcupBinDir
  cabalFile <- lift $ parseRel ("cabal-" <> verToBS ver)
-  liftIO $ hideError doesNotExistErrorType $ deleteFile (bindir </> cabalFile)
+  liftIO $ hideError doesNotExistErrorType $ deleteFile (binDir </> cabalFile)

  when (maybe False (== ver) cSet) $ do
-    cVers <- liftIO $ fmap rights $ getInstalledCabals
+    cVers <- lift $ fmap rights $ getInstalledCabals
    case headMay . reverse . sort $ cVers of
      Just latestver -> setCabal latestver
      Nothing        -> liftIO $ hideError doesNotExistErrorType $ deleteFile
-        (bindir </> [rel|cabal|])
+        (binDir </> [rel|cabal|])



@@ -653,18 +714,19 @@ rmCabalVer ver = do
    ------------------


-getDebugInfo :: (MonadLogger m, MonadCatch m, MonadIO m)
+getDebugInfo :: (MonadReader Settings m, MonadLogger m, MonadCatch m, MonadIO m)
             => Excepts
                  '[NoCompatiblePlatform , NoCompatibleArch , DistroNotFound]
                  m
                  DebugInfo
 getDebugInfo = do
-  diBaseDir  <- liftIO $ ghcupBaseDir
-  diBinDir   <- liftIO $ ghcupBinDir
-  diGHCDir   <- liftIO $ ghcupGHCBaseDir
-  diCacheDir <- liftIO $ ghcupCacheDir
-  diArch     <- lE getArchitecture
-  diPlatform <- liftE $ getPlatform
+  Settings {dirs = Dirs {..}} <- lift ask
+  let diBaseDir  = baseDir
+  let diBinDir   = binDir
+  diGHCDir       <- lift ghcupGHCBaseDir
+  let diCacheDir = cacheDir
+  diArch         <- lE getArchitecture
+  diPlatform     <- liftE $ getPlatform
  pure $ DebugInfo { .. }


@@ -703,6 +765,7 @@ compileGHC :: ( MonadMask m
                 , NotFoundInPATH
                 , PatchFailed
                 , UnknownArchive
+                 , TarDirDoesNotExist
 #if !defined(TAR)
                 , ArchiveResult
 #endif
@@ -711,7 +774,7 @@ compileGHC :: ( MonadMask m
                ()
 compileGHC dls tver bstrap jobs mbuildConfig patchdir aargs PlatformRequest {..} = do
  lift $ $(logDebug) [i|Requested to compile: #{tver} with #{bstrap}|]
-  whenM (liftIO $ ghcInstalled tver)
+  whenM (lift $ ghcInstalled tver)
        (throwE $ AlreadyInstalled GHC (tver ^. tvVersion))

  -- download source tarball
@@ -728,8 +791,8 @@ compileGHC dls tver bstrap jobs mbuildConfig patchdir aargs PlatformRequest {..}
  bghc <- case bstrap of
    Right g    -> pure $ Right g
    Left  bver -> Left <$> parseRel ("ghc-" <> verToBS bver)
-  let workdir = maybe id (flip (</>)) (view dlSubdir dlInfo) $ tmpUnpack
-  ghcdir <- liftIO $ ghcupGHCDir tver
+  workdir <- maybe (pure tmpUnpack) (liftE . intoSubdir tmpUnpack) (view dlSubdir dlInfo)
+  ghcdir <- lift $ ghcupGHCDir tver

  liftE $ runBuildAction
    tmpUnpack
@@ -793,7 +856,6 @@ Stage1Only = YES|]
             )
          ++ fmap E.encodeUtf8 aargs
          )
-          [rel|ghc-conf|]
          (Just workdir)
          (Just (("GHC", toFilePath bghcPath) : cEnv))
      | otherwise -> do
@@ -809,7 +871,6 @@ Stage1Only = YES|]
             )
          ++ fmap E.encodeUtf8 aargs
          )
-          [rel|ghc-conf|]
          (Just workdir)
          (Just cEnv)

@@ -883,6 +944,7 @@ compileCabal :: ( MonadReader Settings m
                   , NotInstalled
                   , PatchFailed
                   , UnknownArchive
+                   , TarDirDoesNotExist
 #if !defined(TAR)
                   , ArchiveResult
 #endif
@@ -892,14 +954,14 @@ compileCabal :: ( MonadReader Settings m
 compileCabal dls tver bghc jobs patchdir PlatformRequest{..} = do
  lift $ $(logDebug) [i|Requested to compile: #{tver} with ghc-#{bghc}|]

-  bindir <- liftIO ghcupBinDir
+  Settings {dirs = Dirs {..}} <- lift ask

  whenM
-      (liftIO $ cabalInstalled tver >>= \a ->
+      (lift (cabalInstalled tver) >>= \a -> liftIO $
        handleIO (\_ -> pure False)
          $ fmap (\x -> a && isSymbolicLink x)
          -- ignore when the installation is a legacy cabal (binary, not symlink)
-          $ getSymbolicLinkStatus (toFilePath (bindir </> [rel|cabal|]))
+          $ getSymbolicLinkStatus (toFilePath (binDir </> [rel|cabal|]))
      )
    $ (throwE $ AlreadyInstalled Cabal tver)

@@ -912,18 +974,18 @@ compileCabal dls tver bghc jobs patchdir PlatformRequest{..} = do
  liftE $ unpackToDir tmpUnpack dl
  void $ liftIO $ darwinNotarization _rPlatform tmpUnpack

-  let workdir = maybe id (flip (</>)) (view dlSubdir dlInfo) $ tmpUnpack
+  workdir <- maybe (pure tmpUnpack) (liftE . intoSubdir tmpUnpack) (view dlSubdir dlInfo)

  cbin         <- liftE $ runBuildAction tmpUnpack Nothing (compile workdir)

  destFileName <- lift $ parseRel ("cabal-" <> verToBS tver)
  handleIO (throwE . CopyError . show) $ liftIO $ copyFile
    cbin
-    (bindir </> destFileName)
+    (binDir </> destFileName)
    Overwrite

  -- create symlink if this is the latest version
-  cVers <- liftIO $ fmap rights $ getInstalledCabals
+  cVers <- lift $ fmap rights $ getInstalledCabals
  let lInstCabal = headMay . reverse . sort $ cVers
  when (maybe True (tver >=) lInstCabal) $ liftE $ setCabal tver

@@ -966,7 +1028,6 @@ compileCabal dls tver bghc jobs patchdir PlatformRequest{..} = do
    lEM $ execLogged "./bootstrap.sh"
                              False
                              (maybe [] (\j -> ["-j", fS (show j)]) jobs)
-                              [rel|cabal-bootstrap|]
                              (Just workdir)
                              (Just newEnv)
    pure $ (tmp </> [rel|bin/cabal|])
@@ -1004,6 +1065,7 @@ upgradeGHCup :: ( MonadMask m
                  m
                  Version
 upgradeGHCup dls mtarget force pfreq = do
+  Settings {dirs = Dirs {..}} <- lift ask
  lift $ $(logInfo) [i|Upgrading GHCup...|]
  let latestVer = fromJust $ getLatest dls GHCup
  when (not force && (latestVer <= pvpToVersion ghcUpVer)) $ throwE NoUpdate
@@ -1011,18 +1073,12 @@ upgradeGHCup dls mtarget force pfreq = do
  tmp   <- lift withGHCupTmpDir
  let fn = [rel|ghcup|]
  p <- liftE $ download dli tmp (Just fn)
-  let fileMode' =
-        newFilePerms
-          `unionFileModes` ownerExecuteMode
-          `unionFileModes` groupExecuteMode
-          `unionFileModes` otherExecuteMode
-  binDir <- liftIO $ ghcupBinDir
  let fullDest = fromMaybe (binDir </> fn) mtarget
  liftIO $ hideError NoSuchThing $ deleteFile fullDest
  handleIO (throwE . CopyError . show) $ liftIO $ copyFile p
                                                           fullDest
                                                           Overwrite
-  liftIO $ setFileMode (toFilePath fullDest) fileMode'
+  lift $ chmod_777 fullDest
  pure latestVer


@@ -1034,13 +1090,24 @@ upgradeGHCup dls mtarget force pfreq = do

 -- | Creates @ghc-x.y.z@ and @ghc-x.y@ symlinks. This is used for
 -- both installing from source and bindist.
-postGHCInstall :: (MonadLogger m, MonadThrow m, MonadFail m, MonadIO m)
+postGHCInstall :: ( MonadReader Settings m
+                  , MonadLogger m
+                  , MonadThrow m
+                  , MonadFail m
+                  , MonadIO m
+                  , MonadCatch m
+                  )
               => GHCTargetVersion
               -> Excepts '[NotInstalled] m ()
-postGHCInstall ver@GHCTargetVersion{..} = do
+postGHCInstall ver@GHCTargetVersion {..} = do
  void $ liftE $ setGHC ver SetGHC_XYZ

  -- Create ghc-x.y symlinks. This may not be the current
  -- version, create it regardless.
-  (mj, mi) <- getMajorMinorV _tvVersion
-  getGHCForMajor mj mi _tvTarget >>= mapM_ (\v -> liftE $ setGHC v SetGHC_XY)
+  v' <-
+    handle (\(e :: ParseError) -> lift $ $(logWarn) [i|#{e}|] >> pure Nothing)
+    $ fmap Just
+    $ getMajorMinorV _tvVersion
+  forM_ v' $ \(mj, mi) -> lift (getGHCForMajor mj mi _tvTarget)
+    >>= mapM_ (\v -> liftE $ setGHC v SetGHC_XY)
+
--- a/lib/GHCup/Data/GHCupDownloads.hs
+++ b/lib/GHCup/Data/GHCupDownloads.hs
--- a/lib/GHCup/Data/GHCupInfo.hs
+++ b/lib/GHCup/Data/GHCupInfo.hs
@@ -1,20 +0,0 @@
-{-|
-Module      : GHCup.Data.GHCupInfo
-Description :
-Copyright   : (c) Julian Ospald, 2020
-License     : GPL-3
-Maintainer  : hasufell@hasufell.de
-Stability   : experimental
-Portability : POSIX
-}
-module GHCup.Data.GHCupInfo where
-
-import           GHCup.Data.GHCupDownloads
-import           GHCup.Data.ToolRequirements
-import           GHCup.Types
-
-
-ghcupInfo :: GHCupInfo
-ghcupInfo = GHCupInfo { _toolRequirements = toolRequirements
-                      , _ghcupDownloads   = ghcupDownloads
-                      }
--- a/lib/GHCup/Data/ToolRequirements.hs
+++ b/lib/GHCup/Data/ToolRequirements.hs
@@ -1,156 +0,0 @@
-{-# LANGUAGE OverloadedStrings #-}
-{-# LANGUAGE QuasiQuotes       #-}
-
-{-|
-Module      : GHCup.Data.ToolRequirements
-Description : Tool requirements
-Copyright   : (c) Julian Ospald, 2020
-License     : GPL-3
-Maintainer  : hasufell@hasufell.de
-Stability   : experimental
-Portability : POSIX
-}
-module GHCup.Data.ToolRequirements where
-
-import           GHCup.Types
-import           GHCup.Utils.String.QQ
-import           GHCup.Utils.Version.QQ
-
-import qualified Data.Map                      as M
-
-
-
-- | Currently 'GHC' is used for both GHC and cabal to simplify
-- this, until we need actual separation.
-toolRequirements :: ToolRequirements
-toolRequirements = M.fromList
-  [ ( GHC
-    , M.fromList
-      [ ( Nothing
-        , M.fromList
-          [ ( Linux UnknownLinux
-            , M.fromList
-              [ ( Nothing
-                , Requirements
-                  []
-                  [s|You need the following packages: curl g++ gcc gmp make ncurses realpath xz-utils. Consult your distro documentation on the exact names of those packages.|]
-                )
-              ]
-            )
-          , ( Linux Alpine
-            , M.fromList
-              [ ( Nothing
-                , Requirements
-                  [ "curl"
-                  , "gcc"
-                  , "g++"
-                  , "gmp-dev"
-                  , "ncurses-dev"
-                  , "libffi-dev"
-                  , "make"
-                  , "xz"
-                  , "tar"
-                  , "perl"
-                  ]
-                  ""
-                )
-              ]
-            )
-          , ( Linux Ubuntu
-            , M.fromList
-              [ ( Nothing
-                , Requirements
-                  [ "build-essential"
-                  , "curl"
-                  , "libffi-dev"
-                  , "libffi6"
-                  , "libgmp-dev"
-                  , "libgmp10"
-                  , "libncurses-dev"
-                  , "libncurses5"
-                  , "libtinfo5"
-                  ]
-                  ""
-                )
-              ]
-            )
-          , ( Linux Debian
-            , M.fromList
-              [ ( Nothing
-                , Requirements
-                  [ "build-essential"
-                  , "curl"
-                  , "libffi-dev"
-                  , "libffi6"
-                  , "libgmp-dev"
-                  , "libgmp10"
-                  , "libncurses-dev"
-                  , "libncurses5"
-                  , "libtinfo5"
-                  ]
-                  ""
-                )
-              ]
-            )
-          , ( Linux CentOS
-            , M.fromList
-              [ ( Nothing
-                , Requirements
-                  [ "gcc"
-                  , "gcc-c++"
-                  , "gmp"
-                  , "gmp-devel"
-                  , "make"
-                  , "ncurses"
-                  , "ncurses-compat-libs"
-                  , "xz"
-                  , "perl"
-                  ]
-                  ""
-                ),
-              ( Just [vers|7|]
-                , Requirements
-                  [ "gcc"
-                  , "gcc-c++"
-                  , "gmp"
-                  , "gmp-devel"
-                  , "make"
-                  , "ncurses"
-                  , "xz"
-                  , "perl"
-                  ]
-                  ""
-                )
-              ]
-            )
-          , ( Darwin
-            , M.fromList
-              [ ( Nothing
-                , Requirements
-                  []
-                  "On OS X, in the course of running ghcup you will be given a dialog box to install the command line tools. Accept and the requirements will be installed for you. You will then need to run the command again."
-                )
-              ]
-            )
-          , ( FreeBSD
-            , M.fromList
-              [ ( Nothing
-                , Requirements
-                  [ "curl"
-                  , "gcc"
-                  , "gmp"
-                  , "gmake"
-                  , "ncurses"
-                  , "perl5"
-                  , "libffi"
-                  , "libiconv"
-                  ]
-                  ""
-                )
-              ]
-            )
-          ]
-        )
-      ]
-    )
-  ]
--- a/lib/GHCup/Download.hs
+++ b/lib/GHCup/Download.hs
@@ -13,7 +13,7 @@
 Module      : GHCup.Download
 Description : Downloading
 Copyright   : (c) Julian Ospald, 2020
-License     : GPL-3
+License     : LGPL-3.0
 Maintainer  : hasufell@hasufell.de
 Stability   : experimental
 Portability : POSIX
@@ -52,6 +52,7 @@ import           Control.Monad.Reader
 import           Control.Monad.Trans.Resource
                                         hiding ( throwM )
 import           Data.Aeson
+import           Data.Bifunctor
 import           Data.ByteString                ( ByteString )
 #if defined(INTERNAL_DOWNLOADER)
 import           Data.CaseInsensitive           ( CI )
@@ -88,6 +89,7 @@ import qualified Data.Map.Strict               as M
 import qualified Data.Text                     as T
 #endif
 import qualified Data.Text.Encoding            as E
+import qualified Data.Yaml                     as Y
 import qualified System.Posix.Files.ByteString as PF
 import qualified System.Posix.RawFilePath.Directory
                                               as RD
@@ -103,7 +105,7 @@ import qualified System.Posix.RawFilePath.Directory


 -- | Like 'getDownloads', but tries to fall back to
-- cached ~/.ghcup/cache/ghcup-<format-ver>.json
+-- cached ~/.ghcup/cache/ghcup-<format-ver>.yaml
 getDownloadsF :: ( FromJSONKey Tool
                 , FromJSONKey Version
                 , FromJSON VersionInfo
@@ -131,17 +133,17 @@ getDownloadsF urlSource = do
    (OwnSpec   _) -> liftE $ getDownloads urlSource
 where
  readFromCache = do
+    Settings {dirs = Dirs {..}} <- lift ask
    lift $ $(logWarn)
      [i|Could not get download info, trying cached version (this may not be recent!)|]
    let path = view pathL' ghcupURL
-    cacheDir  <- liftIO $ ghcupCacheDir
-    json_file <- (cacheDir </>) <$> urlBaseName path
+    yaml_file <- (cacheDir </>) <$> urlBaseName path
    bs        <-
      handleIO' NoSuchThing
-                (\_ -> throwE $ FileDoesNotExistError (toFilePath json_file))
+                (\_ -> throwE $ FileDoesNotExistError (toFilePath yaml_file))
      $ liftIO
-      $ readFile json_file
-    lE' JSONDecodeError $ eitherDecode' bs
+      $ readFile yaml_file
+    lE' JSONDecodeError $ bimap show id $ Y.decodeEither' (L.toStrict bs)


 -- | Downloads the download information! But only if we need to ;P
@@ -162,10 +164,10 @@ getDownloads urlSource = do
  case urlSource of
    GHCupURL -> do
      bs <- reThrowAll DownloadFailed $ smartDl ghcupURL
-      lE' JSONDecodeError $ eitherDecode' bs
+      lE' JSONDecodeError $ bimap show id $ Y.decodeEither' (L.toStrict bs)
    (OwnSource url) -> do
      bs <- reThrowAll DownloadFailed $ downloadBS url
-      lE' JSONDecodeError $ eitherDecode' bs
+      lE' JSONDecodeError $ bimap show id $ Y.decodeEither' (L.toStrict bs)
    (OwnSpec av) -> pure $ av

 where
@@ -198,8 +200,8 @@ getDownloads urlSource = do
               m1
               L.ByteString
  smartDl uri' = do
+    Settings {dirs = Dirs {..}} <- lift ask
    let path = view pathL' uri'
-    cacheDir  <- liftIO $ ghcupCacheDir
    json_file <- (cacheDir </>) <$> urlBaseName path
    e         <- liftIO $ doesFileExist json_file
    if e
@@ -224,7 +226,7 @@ getDownloads urlSource = do
          else -- access in less than 5 minutes, re-use file
               liftIO $ readFile json_file
      else do
-        liftIO $ createDirIfMissing newDirPerms cacheDir
+        liftIO $ createDirRecursive newDirPerms cacheDir
        getModTime >>= \case
          Just modTime -> dlWithMod modTime json_file
          Nothing -> do
@@ -390,15 +392,15 @@ downloadCached dli mfn = do
  cache <- lift getCache
  case cache of
    True -> do
-      cachedir <- liftIO $ ghcupCacheDir
+      Settings {dirs = Dirs {..}} <- lift ask
      fn       <- maybe (urlBaseName $ view (dlUri % pathL') dli) pure mfn
-      let cachfile = cachedir </> fn
+      let cachfile = cacheDir </> fn
      fileExists <- liftIO $ doesFileExist cachfile
      if
        | fileExists -> do
          liftE $ checkDigest dli cachfile
          pure $ cachfile
-        | otherwise -> liftE $ download dli cachedir mfn
+        | otherwise -> liftE $ download dli cacheDir mfn
    False -> do
      tmp <- lift withGHCupTmpDir
      liftE $ download dli tmp mfn
--- a/lib/GHCup/Download/IOStreams.hs
+++ b/lib/GHCup/Download/IOStreams.hs
@@ -13,6 +13,7 @@ module GHCup.Download.IOStreams where

 import           GHCup.Download.Utils
 import           GHCup.Errors
+import           GHCup.Types
 import           GHCup.Types.Optics
 import           GHCup.Types.JSON               ( )
 import           GHCup.Utils.File
--- a/lib/GHCup/Errors.hs
+++ b/lib/GHCup/Errors.hs
@@ -7,7 +7,7 @@
 Module      : GHCup.Errors
 Description : GHCup error types
 Copyright   : (c) Julian Ospald, 2020
-License     : GPL-3
+License     : LGPL-3.0
 Maintainer  : hasufell@hasufell.de
 Stability   : experimental
 Portability : POSIX
@@ -89,6 +89,9 @@ data JSONError = JSONDecodeError String
 data FileDoesNotExistError = FileDoesNotExistError ByteString
  deriving Show

+data TarDirDoesNotExist = TarDirDoesNotExist TarDir
+  deriving Show
+
 -- | File digest verification failed.
 data DigestError = DigestError Text Text
  deriving Show
--- a/lib/GHCup/Platform.hs
+++ b/lib/GHCup/Platform.hs
@@ -10,7 +10,7 @@
 Module      : GHCup.Plaform
 Description : Retrieving platform information
 Copyright   : (c) Julian Ospald, 2020
-License     : GPL-3
+License     : LGPL-3.0
 Maintainer  : hasufell@hasufell.de
 Stability   : experimental
 Portability : POSIX
--- a/lib/GHCup/Requirements.hs
+++ b/lib/GHCup/Requirements.hs
@@ -4,7 +4,7 @@
 Module      : GHCup.Requirements
 Description : Requirements utilities
 Copyright   : (c) Julian Ospald, 2020
-License     : GPL-3
+License     : LGPL-3.0
 Maintainer  : hasufell@hasufell.de
 Stability   : experimental
 Portability : POSIX
--- a/lib/GHCup/Types.hs
+++ b/lib/GHCup/Types.hs
@@ -1,23 +1,30 @@
+{-# OPTIONS_GHC -Wno-orphans #-}
+
 {-# LANGUAGE CPP               #-}
 {-# LANGUAGE DeriveGeneric     #-}
 {-# LANGUAGE OverloadedStrings #-}
+{-# LANGUAGE TypeSynonymInstances #-}
+{-# LANGUAGE FlexibleInstances #-}

 {-|
 Module      : GHCup.Types
 Description : GHCup types
 Copyright   : (c) Julian Ospald, 2020
-License     : GPL-3
+License     : LGPL-3.0
 Maintainer  : hasufell@hasufell.de
 Stability   : experimental
 Portability : POSIX
 -}
 module GHCup.Types where

+import           Control.Concurrent.MVar
+import           Data.ByteString                ( ByteString )
 import           Data.Map.Strict                ( Map )
 import           Data.Text                      ( Text )
 import           Data.Versions
 import           HPath
 import           URI.ByteString
+import           System.Posix.Types

 import qualified GHC.Generics                  as GHC

@@ -92,6 +99,7 @@ data VersionInfo = VersionInfo
 -- | A tag. These are currently attached to a version of a tool.
 data Tag = Latest
         | Recommended
+         | Prerelease
         | Base PVP
         | UnknownTag String  -- ^ used for upwardscompat
         deriving (Ord, Eq, Show) -- FIXME: manual JSON instance
@@ -136,7 +144,7 @@ data LinuxDistro = Debian
 -- to download, extract and install a tool.
 data DownloadInfo = DownloadInfo
  { _dlUri    :: URI
-  , _dlSubdir :: Maybe (Path Rel)
+  , _dlSubdir :: Maybe TarDir
  , _dlHash   :: Text
  }
  deriving (Eq, Show)
@@ -149,6 +157,12 @@ data DownloadInfo = DownloadInfo
    --------------


+-- | How to descend into a tar archive.
+data TarDir = RealDir (Path Rel)
+            | RegexDir String     -- ^ will be compiled to regex, the first match will "win"
+            deriving (Eq, Show)
+
+
 -- | Where to fetch GHCupDownloads from.
 data URLSource = GHCupURL
               | OwnSource URI
@@ -156,15 +170,48 @@ data URLSource = GHCupURL
               deriving Show


+data ProcessError = NonZeroExit Int ByteString [ByteString]
+                  | PTerminated ByteString [ByteString]
+                  | PStopped ByteString [ByteString]
+                  | NoSuchPid ByteString [ByteString]
+                  deriving (Eq, Show)
+
+data ProcState = PRunning ProcessID
+               | PExited (Either ProcessError ())
+  deriving Eq
+
+type ExecCb =    Bool       -- verbose
+              -> Fd         -- log file fd
+              -> Fd         -- input fd to read from
+              -> MVar ProcState  -- state of the producing process
+              -> ByteString -- log filename
+              -> IO ()
+
+instance Show ExecCb where
+  show _ = "**ExecCb**"
+
+
 data Settings = Settings
-  { cache      :: Bool
+  { -- set by user
+    cache      :: Bool
  , noVerify   :: Bool
  , keepDirs   :: KeepDirs
  , downloader :: Downloader
  , verbose    :: Bool
+
+    -- set on app start
+  , dirs       :: Dirs
+  , execCb     :: ExecCb
  }
  deriving Show

+data Dirs = Dirs
+  { baseDir  :: Path Abs
+  , binDir   :: Path Abs
+  , cacheDir :: Path Abs
+  , logsDir  :: Path Abs
+  }
+  deriving Show

 data KeepDirs = Always
              | Errors
--- a/lib/GHCup/Types/JSON.hs
+++ b/lib/GHCup/Types/JSON.hs
@@ -14,7 +14,7 @@
 Module      : GHCup.Types.JSON
 Description : GHCup JSON types/instances
 Copyright   : (c) Julian Ospald, 2020
-License     : GPL-3
+License     : LGPL-3.0
 Maintainer  : hasufell@hasufell.de
 Stability   : experimental
 Portability : POSIX
@@ -24,6 +24,7 @@ module GHCup.Types.JSON where
 import           GHCup.Types
 import           GHCup.Utils.Prelude

+import           Control.Applicative            ( (<|>) )
 import           Data.Aeson
 import           Data.Aeson.TH
 import           Data.Aeson.Types
@@ -53,6 +54,7 @@ deriveJSON defaultOptions { fieldLabelModifier = removeLensFieldLabel } ''Requir
 instance ToJSON Tag where
  toJSON Latest             = String "Latest"
  toJSON Recommended        = String "Recommended"
+  toJSON Prerelease         = String "Prerelease"
  toJSON (Base       pvp'') = String ("base-" <> prettyPVP pvp'')
  toJSON (UnknownTag x    ) = String (T.pack x)

@@ -60,6 +62,7 @@ instance FromJSON Tag where
  parseJSON = withText "Tag" $ \t -> case T.unpack t of
    "Latest"                             -> pure Latest
    "Recommended"                        -> pure Recommended
+    "Prerelease"                         -> pure Prerelease
    ('b' : 'a' : 's' : 'e' : '-' : ver') -> case pvp (T.pack ver') of
      Right x -> pure $ Base x
      Left  e -> fail . show $ e
@@ -191,3 +194,18 @@ instance FromJSON (Path Rel) where
    case parseRel d of
      Right x -> pure x
      Left  e -> fail $ "Failure in HPath Rel (FromJSON)" <> show e
+
+
+instance ToJSON TarDir where
+  toJSON (RealDir  p) = toJSON p
+  toJSON (RegexDir r) = object ["RegexDir" .= r]
+
+instance FromJSON TarDir where
+  parseJSON v = realDir v <|> regexDir v
+   where
+    realDir = withText "TarDir" $ \t -> do
+      fp <- parseJSON (String t)
+      pure (RealDir fp)
+    regexDir = withObject "TarDir" $ \o -> do
+      r <- o .: "RegexDir"
+      pure $ RegexDir r
--- a/lib/GHCup/Types/Optics.hs
+++ b/lib/GHCup/Types/Optics.hs
@@ -4,7 +4,7 @@
 Module      : GHCup.Types.Optics
 Description : GHCup optics
 Copyright   : (c) Julian Ospald, 2020
-License     : GPL-3
+License     : LGPL-3.0
 Maintainer  : hasufell@hasufell.de
 Stability   : experimental
 Portability : POSIX
--- a/lib/GHCup/Utils.hs
+++ b/lib/GHCup/Utils.hs
@@ -10,7 +10,7 @@
 Module      : GHCup.Utils
 Description : GHCup domain specific utilities
 Copyright   : (c) Julian Ospald, 2020
-License     : GPL-3
+License     : LGPL-3.0
 Maintainer  : hasufell@hasufell.de
 Stability   : experimental
 Portability : POSIX
@@ -48,7 +48,9 @@ import           Control.Monad.Logger
 import           Control.Monad.Reader
 import           Data.ByteString                ( ByteString )
 import           Data.Either
+import           Data.Foldable
 import           Data.List
+import           Data.List.Split
 import           Data.Maybe
 import           Data.String.Interpolate
 import           Data.Text                      ( Text )
@@ -97,20 +99,24 @@ import qualified Text.Megaparsec               as MP


 -- | The symlink destination of a ghc tool.
-ghcLinkDestination :: ByteString -- ^ the tool, such as 'ghc', 'haddock' etc.
+ghcLinkDestination :: (MonadReader Settings m, MonadThrow m, MonadIO m)
+                   => ByteString -- ^ the tool, such as 'ghc', 'haddock' etc.
                   -> GHCTargetVersion
-                   -> ByteString
-ghcLinkDestination tool ver =
-  "../ghc/" <> E.encodeUtf8 (prettyTVer ver) <> "/bin/" <> tool
+                   -> m ByteString
+ghcLinkDestination tool ver = do
+  Settings {dirs = Dirs {..}} <- ask
+  t <- parseRel tool
+  ghcd <- ghcupGHCDir ver
+  pure (relativeSymlink binDir (ghcd </> [rel|bin|] </> t))


 -- | Removes the minor GHC symlinks, e.g. ghc-8.6.5.
-rmMinorSymlinks :: (MonadIO m, MonadLogger m) => GHCTargetVersion -> m ()
+rmMinorSymlinks :: (MonadReader Settings m, MonadIO m, MonadLogger m) => GHCTargetVersion -> m ()
 rmMinorSymlinks GHCTargetVersion {..} = do
-  bindir <- liftIO $ ghcupBinDir
+  Settings {dirs = Dirs {..}} <- ask

  files  <- liftIO $ findFiles'
-    bindir
+    binDir
    (  maybe mempty (\x -> MP.chunk (x <> "-")) _tvTarget
    *> parseUntil1 (MP.chunk $ prettyVer _tvVersion)
    *> (MP.chunk $ prettyVer _tvVersion)
@@ -118,42 +124,41 @@ rmMinorSymlinks GHCTargetVersion {..} = do
    )

  forM_ files $ \f -> do
-    let fullF = (bindir </> f)
+    let fullF = (binDir </> f)
    $(logDebug) [i|rm -f #{toFilePath fullF}|]
    liftIO $ hideError doesNotExistErrorType $ deleteFile fullF


 -- | Removes the set ghc version for the given target, if any.
-rmPlain :: (MonadLogger m, MonadThrow m, MonadFail m, MonadIO m)
+rmPlain :: (MonadReader Settings m, MonadLogger m, MonadThrow m, MonadFail m, MonadIO m)
  => Maybe Text -- ^ target
        -> Excepts '[NotInstalled] m ()
 rmPlain target = do
-  mtv <- ghcSet target
+  Settings {dirs = Dirs {..}} <- lift ask
+  mtv <- lift $ ghcSet target
  forM_ mtv $ \tv -> do
    files  <- liftE $ ghcToolFiles tv
-    bindir <- liftIO $ ghcupBinDir
    forM_ files $ \f -> do
-      let fullF = (bindir </> f)
+      let fullF = (binDir </> f)
      lift $ $(logDebug) [i|rm -f #{toFilePath fullF}|]
      liftIO $ hideError doesNotExistErrorType $ deleteFile fullF
    -- old ghcup
-    let hdc_file = (bindir </> [rel|haddock-ghc|])
+    let hdc_file = (binDir </> [rel|haddock-ghc|])
    lift $ $(logDebug) [i|rm -f #{toFilePath hdc_file}|]
    liftIO $ hideError doesNotExistErrorType $ deleteFile hdc_file


 -- | Remove the major GHC symlink, e.g. ghc-8.6.
-rmMajorSymlinks :: (MonadThrow m, MonadLogger m, MonadIO m)
+rmMajorSymlinks :: (MonadReader Settings m, MonadThrow m, MonadLogger m, MonadIO m)
                => GHCTargetVersion
                -> m ()
 rmMajorSymlinks GHCTargetVersion {..} = do
+  Settings {dirs = Dirs {..}} <- ask
  (mj, mi) <- getMajorMinorV _tvVersion
  let v' = intToText mj <> "." <> intToText mi

-  bindir <- liftIO ghcupBinDir
-
  files  <- liftIO $ findFiles'
-    bindir
+    binDir
    (  maybe mempty (\x -> MP.chunk (x <> "-")) _tvTarget
    *> parseUntil1 (MP.chunk v')
    *> MP.chunk v'
@@ -161,7 +166,7 @@ rmMajorSymlinks GHCTargetVersion {..} = do
    )

  forM_ files $ \f -> do
-    let fullF = (bindir </> f)
+    let fullF = (binDir </> f)
    $(logDebug) [i|rm -f #{toFilePath fullF}|]
    liftIO $ hideError doesNotExistErrorType $ deleteFile fullF

@@ -174,59 +179,61 @@ rmMajorSymlinks GHCTargetVersion {..} = do


 -- | Whethe the given GHC versin is installed.
-ghcInstalled :: GHCTargetVersion -> IO Bool
+ghcInstalled :: (MonadIO m, MonadReader Settings m, MonadThrow m) => GHCTargetVersion -> m Bool
 ghcInstalled ver = do
  ghcdir <- ghcupGHCDir ver
-  doesDirectoryExist ghcdir
+  liftIO $ doesDirectoryExist ghcdir


 -- | Whether the given GHC version is installed from source.
-ghcSrcInstalled :: GHCTargetVersion -> IO Bool
+ghcSrcInstalled :: (MonadIO m, MonadReader Settings m, MonadThrow m) => GHCTargetVersion -> m Bool
 ghcSrcInstalled ver = do
  ghcdir <- ghcupGHCDir ver
-  doesFileExist (ghcdir </> ghcUpSrcBuiltFile)
+  liftIO $ doesFileExist (ghcdir </> ghcUpSrcBuiltFile)


 -- | Whether the given GHC version is set as the current.
-ghcSet :: (MonadThrow m, MonadIO m)
+ghcSet :: (MonadReader Settings m, MonadThrow m, MonadIO m)
       => Maybe Text   -- ^ the target of the GHC version, if any
                       --  (e.g. armv7-unknown-linux-gnueabihf)
       -> m (Maybe GHCTargetVersion)
 ghcSet mtarget = do
+  Settings {dirs = Dirs {..}} <- ask
  ghc    <- parseRel $ E.encodeUtf8 (maybe "ghc" (<> "-ghc") mtarget)
-  ghcBin <- (</> ghc) <$> liftIO ghcupBinDir
+  let ghcBin = binDir </> ghc

  -- link destination is of the form ../ghc/<ver>/bin/ghc
  -- for old ghcup, it is ../ghc/<ver>/bin/ghc-<ver>
  liftIO $ handleIO' NoSuchThing (\_ -> pure $ Nothing) $ do
    link <- readSymbolicLink $ toFilePath ghcBin
    Just <$> ghcLinkVersion link
+
+ghcLinkVersion :: MonadThrow m => ByteString -> m GHCTargetVersion
+ghcLinkVersion bs = do
+  t <- throwEither $ E.decodeUtf8' bs
+  throwEither $ MP.parse parser "ghcLinkVersion" t
 where
-  ghcLinkVersion :: MonadThrow m => ByteString -> m GHCTargetVersion
-  ghcLinkVersion bs = do
-    t <- throwEither $ E.decodeUtf8' bs
-    throwEither $ MP.parse parser "" t
-   where
-    parser =
-      MP.chunk "../ghc/"
-        *> (do
-             r    <- parseUntil1 (MP.chunk "/")
-             rest <- MP.getInput
-             MP.setInput r
-             x <- ghcTargetVerP
-             MP.setInput rest
-             pure x
-           )
-        <* MP.chunk "/"
-        <* MP.takeRest
-        <* MP.eof
+  parser =
+      (do
+         _    <- parseUntil1 (MP.chunk "/ghc/")
+         _    <- MP.chunk "/ghc/"
+         r    <- parseUntil1 (MP.chunk "/")
+         rest <- MP.getInput
+         MP.setInput r
+         x <- ghcTargetVerP
+         MP.setInput rest
+         pure x
+       )
+      <* MP.chunk "/"
+      <* MP.takeRest
+      <* MP.eof


 -- | Get all installed GHCs by reading ~/.ghcup/ghc/<dir>.
 -- If a dir cannot be parsed, returns left.
-getInstalledGHCs :: MonadIO m => m [Either (Path Rel) GHCTargetVersion]
+getInstalledGHCs :: (MonadReader Settings m, MonadIO m) => m [Either (Path Rel) GHCTargetVersion]
 getInstalledGHCs = do
-  ghcdir <- liftIO $ ghcupGHCBaseDir
+  ghcdir <- ghcupGHCBaseDir
  fs     <- liftIO $ hideErrorDef [NoSuchThing] [] $ getDirsFiles' ghcdir
  forM fs $ \f -> case parseGHCupGHCDir f of
    Right r -> pure $ Right r
@@ -234,43 +241,64 @@ getInstalledGHCs = do


 -- | Get all installed cabals, by matching on @~\/.ghcup\/bin/cabal-*@.
-getInstalledCabals :: IO [Either (Path Rel) Version]
+getInstalledCabals :: (MonadReader Settings m, MonadIO m, MonadCatch m)
+                   => m [Either (Path Rel) Version]
 getInstalledCabals = do
-  bindir <- liftIO $ ghcupBinDir
+  Settings {dirs = Dirs {..}} <- ask
  bins   <- liftIO $ handleIO (\_ -> pure []) $ findFiles
-    bindir
+    binDir
    (makeRegexOpts compExtended execBlank ([s|^cabal-.*$|] :: ByteString))
  vs <- forM bins $ \f -> case fmap version (fmap decUTF8Safe . B.stripPrefix "cabal-" . toFilePath $ f) of
    Just (Right r) -> pure $ Right r
    Just (Left  _) -> pure $ Left f
    Nothing        -> pure $ Left f
  cs <- cabalSet -- for legacy cabal
-  pure $ maybe vs (\x -> Right x:vs) cs
+  pure $ maybe vs (\x -> nub $ Right x:vs) cs


 -- | Whether the given cabal version is installed.
-cabalInstalled :: Version -> IO Bool
+cabalInstalled :: (MonadIO m, MonadReader Settings m, MonadCatch m) => Version -> m Bool
 cabalInstalled ver = do
  vers <- fmap rights $ getInstalledCabals
  pure $ elem ver $ vers


 -- Return the currently set cabal version, if any.
-cabalSet :: (MonadIO m, MonadThrow m) => m (Maybe Version)
+cabalSet :: (MonadReader Settings m, MonadIO m, MonadThrow m, MonadCatch m) => m (Maybe Version)
 cabalSet = do
-  cabalbin <- (</> [rel|cabal|]) <$> liftIO ghcupBinDir
-  mc       <- liftIO $ handleIO (\_ -> pure Nothing) $ fmap Just $ executeOut
-    cabalbin
-    ["--numeric-version"]
-    Nothing
-  fmap join $ forM mc $ \c -> if
-             | not (B.null (_stdOut c))
-             , _exitCode c == ExitSuccess -> do
-                  let reportedVer = fst . B.spanEnd (== _lf) . _stdOut $ c
-                  case version $ decUTF8Safe reportedVer of
-                    Left  e -> throwM e
-                    Right r -> pure $ Just r
-             | otherwise -> pure Nothing
+  Settings {dirs = Dirs {..}} <- ask
+  let cabalbin = binDir </> [rel|cabal|]
+  b        <- handleIO (\_ -> pure False) $ fmap (== SymbolicLink) $ liftIO $ getFileType cabalbin
+  if
+    | b -> do
+      liftIO $ handleIO' NoSuchThing (\_ -> pure $ Nothing) $ do
+        broken <- isBrokenSymlink cabalbin
+        if broken
+          then pure Nothing
+          else do
+            link <- readSymbolicLink $ toFilePath cabalbin
+            Just <$> linkVersion link
+    | otherwise -> do -- legacy behavior
+      mc <- liftIO $ handleIO (\_ -> pure Nothing) $ fmap Just $ executeOut
+        cabalbin
+        ["--numeric-version"]
+        Nothing
+      fmap join $ forM mc $ \c -> if
+        | not (B.null (_stdOut c)), _exitCode c == ExitSuccess -> do
+          let reportedVer = fst . B.spanEnd (== _lf) . _stdOut $ c
+          case version $ decUTF8Safe reportedVer of
+            Left  e -> throwM e
+            Right r -> pure $ Just r
+        | otherwise -> pure Nothing
+ where
+  linkVersion :: MonadThrow m => ByteString -> m Version
+  linkVersion bs = do
+    t <- throwEither $ E.decodeUtf8' bs
+    throwEither $ MP.parse parser "" t
+   where
+    parser =
+      MP.chunk "cabal-" *> version'
+



@@ -295,7 +323,7 @@ matchMajor v' major' minor' = case getMajorMinorV v' of

 -- | Get the latest installed full GHC version that satisfies X.Y.
 -- This reads `ghcupGHCBaseDir`.
-getGHCForMajor :: (MonadIO m, MonadThrow m)
+getGHCForMajor :: (MonadReader Settings m, MonadIO m, MonadThrow m)
               => Int        -- ^ major version component
               -> Int        -- ^ minor version component
               -> Maybe Text -- ^ the target triple
@@ -352,17 +380,16 @@ unpackToDir dest av = do
 #if defined(TAR)
  let untar :: MonadIO m => BL.ByteString -> Excepts '[] m ()
      untar = liftIO . Tar.unpack (toFilePath dest) . Tar.read
+
+      rf :: MonadIO m => Path Abs -> Excepts '[] m BL.ByteString
+      rf = liftIO . readFile
 #else
  let untar :: MonadIO m => BL.ByteString -> Excepts '[ArchiveResult] m ()
      untar = lEM . liftIO . runArchiveM . unpackToDirLazy (T.unpack . decUTF8Safe . toFilePath $ dest)
-#endif

-#if defined(TAR)
-      rf :: MonadIO m => Path Abs -> Excepts '[] m BL.ByteString
-#else
      rf :: MonadIO m => Path Abs -> Excepts '[ArchiveResult] m BL.ByteString
-#endif
      rf = liftIO . readFile
+#endif

  -- extract, depending on file extension
  if
@@ -378,6 +405,28 @@ unpackToDir dest av = do
    | otherwise -> throwE $ UnknownArchive fn


+intoSubdir :: (MonadLogger m, MonadIO m, MonadThrow m, MonadCatch m)
+           => Path Abs       -- ^ unpacked tar dir
+           -> TarDir         -- ^ how to descend
+           -> Excepts '[TarDirDoesNotExist] m (Path Abs)
+intoSubdir bdir tardir = case tardir of
+  RealDir pr -> do
+    whenM (fmap not . liftIO . doesDirectoryExist $ (bdir </> pr))
+          (throwE $ TarDirDoesNotExist tardir)
+    pure (bdir </> pr)
+  RegexDir r -> do
+    let rs = splitOn "/" r
+    foldlM
+      (\y x ->
+        (fmap sort . handleIO (\_ -> pure []) . liftIO . findFiles y . regex $ x) >>= \case
+          []      -> throwE $ TarDirDoesNotExist tardir
+          (p : _) -> pure (y </> p)
+      )
+      bdir
+      rs
+    where regex = makeRegexOpts compIgnoreCase execBlank
+
+


    ------------
@@ -440,11 +489,11 @@ urlBaseName = parseRel . snd . B.breakEnd (== _slash) . urlDecode False
 -- Returns unversioned relative files, e.g.:
 --
 --   - @["hsc2hs","haddock","hpc","runhaskell","ghc","ghc-pkg","ghci","runghc","hp2ps"]@
-ghcToolFiles :: (MonadThrow m, MonadFail m, MonadIO m)
+ghcToolFiles :: (MonadReader Settings m, MonadThrow m, MonadFail m, MonadIO m)
             => GHCTargetVersion
             -> Excepts '[NotInstalled] m [Path Rel]
 ghcToolFiles ver = do
-  ghcdir <- liftIO $ ghcupGHCDir ver
+  ghcdir <- lift $ ghcupGHCDir ver
  let bindir = ghcdir </> [rel|bin|]

  -- fail if ghc is not installed
@@ -501,7 +550,7 @@ make args workdir = do
  spaths    <- catMaybes . fmap parseAbs <$> (liftIO getSearchPath)
  has_gmake <- isJust <$> (liftIO $ searchPath spaths [rel|gmake|])
  let mymake = if has_gmake then "gmake" else "make"
-  execLogged mymake True args [rel|ghc-make|] workdir Nothing
+  execLogged mymake True args workdir Nothing


 -- | Try to apply patches in order. Fails with 'PatchFailed'
@@ -553,24 +602,18 @@ runBuildAction :: (Show (V e), MonadReader Settings m, MonadIO m, MonadMask m)
               -> Excepts '[BuildFailed] m a
 runBuildAction bdir instdir action = do
  Settings {..} <- lift ask
-  v <- flip
-      onException
-      (do
+  let exAction = do
        forM_ instdir $ \dir ->
          liftIO $ hideError doesNotExistErrorType $ deleteDirRecursive dir
        when (keepDirs == Never)
          $ liftIO
          $ hideError doesNotExistErrorType
          $ deleteDirRecursive bdir
-      )
+  v <-
+    flip onException exAction
    $ catchAllE
        (\es -> do
-          forM_ instdir $ \dir ->
-            liftIO $ hideError doesNotExistErrorType $ deleteDirRecursive dir
-          when (keepDirs == Never)
-            $ liftIO
-            $ hideError doesNotExistErrorType
-            $ deleteDirRecursive bdir
+          exAction
          throwE (BuildFailed bdir es)
        )
    $ action
--- a/lib/GHCup/Utils/Dirs.hs
+++ b/lib/GHCup/Utils/Dirs.hs
@@ -1,4 +1,5 @@
 {-# LANGUAGE OverloadedStrings     #-}
+{-# LANGUAGE FlexibleContexts      #-}
 {-# LANGUAGE QuasiQuotes           #-}
 {-# LANGUAGE ViewPatterns          #-}

@@ -6,12 +7,21 @@
 Module      : GHCup.Utils.Dirs
 Description : Definition of GHCup directories
 Copyright   : (c) Julian Ospald, 2020
-License     : GPL-3
+License     : LGPL-3.0
 Maintainer  : hasufell@hasufell.de
 Stability   : experimental
 Portability : POSIX
 -}
-module GHCup.Utils.Dirs where
+module GHCup.Utils.Dirs
+  ( getDirs
+  , ghcupGHCBaseDir
+  , ghcupGHCDir
+  , parseGHCupGHCDir
+  , mkGhcupTmpDir
+  , withGHCupTmpDir
+  , relativeSymlink
+  )
+where


 import           GHCup.Types
@@ -24,6 +34,7 @@ import           Control.Exception.Safe
 import           Control.Monad
 import           Control.Monad.Reader
 import           Control.Monad.Trans.Resource
+import           Data.ByteString                ( ByteString )
 import           Data.Maybe
 import           HPath
 import           HPath.IO
@@ -35,6 +46,7 @@ import           Prelude                 hiding ( abs
 import           System.Posix.Env.ByteString    ( getEnv
                                                , getEnvDefault
                                                )
+import           System.Posix.FilePath   hiding ( (</>) )
 import           System.Posix.Temp.ByteString   ( mkdtemp )

 import qualified Data.ByteString.UTF8          as UTF8
@@ -45,33 +57,117 @@ import qualified Text.Megaparsec               as MP



+    ------------------------------
+    --[ GHCup base directories ]--
+    ------------------------------
+
+
+-- | ~/.ghcup by default
+--
+-- If 'GHCUP_USE_XDG_DIRS' is set (to anything),
+-- then uses 'XDG_DATA_HOME/ghcup' as per xdg spec.
+ghcupBaseDir :: IO (Path Abs)
+ghcupBaseDir = do
+  xdg <- useXDG
+  if xdg
+    then do
+      bdir <- getEnv "XDG_DATA_HOME" >>= \case
+        Just r  -> parseAbs r
+        Nothing -> do
+          home <- liftIO getHomeDirectory
+          pure (home </> [rel|.local/share|])
+      pure (bdir </> [rel|ghcup|])
+    else do
+      bdir <- getEnv "GHCUP_INSTALL_BASE_PREFIX" >>= \case
+        Just r  -> parseAbs r
+        Nothing -> liftIO getHomeDirectory
+      pure (bdir </> [rel|.ghcup|])
+
+
+-- | If 'GHCUP_USE_XDG_DIRS' is set (to anything),
+-- then uses 'XDG_BIN_HOME' env var or defaults to '~/.local/bin'
+-- (which, sadly is not strictly xdg spec).
+ghcupBinDir :: IO (Path Abs)
+ghcupBinDir = do
+  xdg <- useXDG
+  if xdg
+    then do
+      getEnv "XDG_BIN_HOME" >>= \case
+        Just r  -> parseAbs r
+        Nothing -> do
+          home <- liftIO getHomeDirectory
+          pure (home </> [rel|.local/bin|])
+    else ghcupBaseDir <&> (</> [rel|bin|])
+
+
+-- | Defaults to '~/.ghcup/cache'.
+--
+-- If 'GHCUP_USE_XDG_DIRS' is set (to anything),
+-- then uses 'XDG_CACHE_HOME/ghcup' as per xdg spec.
+ghcupCacheDir :: IO (Path Abs)
+ghcupCacheDir = do
+  xdg <- useXDG
+  if xdg
+    then do
+      bdir <- getEnv "XDG_CACHE_HOME" >>= \case
+        Just r  -> parseAbs r
+        Nothing -> do
+          home <- liftIO getHomeDirectory
+          pure (home </> [rel|.cache|])
+      pure (bdir </> [rel|ghcup|])
+    else ghcupBaseDir <&> (</> [rel|cache|])
+
+
+-- | Defaults to '~/.ghcup/logs'.
+--
+-- If 'GHCUP_USE_XDG_DIRS' is set (to anything),
+-- then uses 'XDG_CACHE_HOME/ghcup/logs' as per xdg spec.
+ghcupLogsDir :: IO (Path Abs)
+ghcupLogsDir = do
+  xdg <- useXDG
+  if xdg
+    then do
+      bdir <- getEnv "XDG_CACHE_HOME" >>= \case
+        Just r  -> parseAbs r
+        Nothing -> do
+          home <- liftIO getHomeDirectory
+          pure (home </> [rel|.cache|])
+      pure (bdir </> [rel|ghcup/logs|])
+    else ghcupBaseDir <&> (</> [rel|logs|])
+
+
+getDirs :: IO Dirs
+getDirs = do
+  baseDir  <- ghcupBaseDir
+  binDir   <- ghcupBinDir
+  cacheDir <- ghcupCacheDir
+  logsDir  <- ghcupLogsDir
+  pure Dirs { .. }
+
+
+
    -------------------------
    --[ GHCup directories ]--
    -------------------------


-- | ~/.ghcup by default
-ghcupBaseDir :: IO (Path Abs)
-ghcupBaseDir = do
-  bdir <- getEnv "GHCUP_INSTALL_BASE_PREFIX" >>= \case
-    Just r  -> parseAbs r
-    Nothing -> liftIO getHomeDirectory
-  pure (bdir </> [rel|.ghcup|])
-
-
 -- | ~/.ghcup/ghc by default.
-ghcupGHCBaseDir :: IO (Path Abs)
-ghcupGHCBaseDir = ghcupBaseDir <&> (</> [rel|ghc|])
+ghcupGHCBaseDir :: (MonadReader Settings m) => m (Path Abs)
+ghcupGHCBaseDir = do
+  Settings {..} <- ask
+  pure (baseDir dirs </> [rel|ghc|])


 -- | Gets '~/.ghcup/ghc/<ghcupGHCDir>'.
 -- The dir may be of the form
 --   * armv7-unknown-linux-gnueabihf-8.8.3
 --   * 8.8.4
-ghcupGHCDir :: GHCTargetVersion -> IO (Path Abs)
+ghcupGHCDir :: (MonadReader Settings m, MonadThrow m)
+            => GHCTargetVersion
+            -> m (Path Abs)
 ghcupGHCDir ver = do
-  ghcbasedir <- ghcupGHCBaseDir
-  verdir     <- parseRel $ E.encodeUtf8 (prettyTVer ver)
+  ghcbasedir    <- ghcupGHCBaseDir
+  verdir        <- parseRel $ E.encodeUtf8 (prettyTVer ver)
  pure (ghcbasedir </> verdir)


@@ -82,16 +178,6 @@ parseGHCupGHCDir (toFilePath -> f) = do
  throwEither $ MP.parse ghcTargetVerP "" fp


-ghcupBinDir :: IO (Path Abs)
-ghcupBinDir = ghcupBaseDir <&> (</> [rel|bin|])
-
-ghcupCacheDir :: IO (Path Abs)
-ghcupCacheDir = ghcupBaseDir <&> (</> [rel|cache|])
-
-ghcupLogsDir :: IO (Path Abs)
-ghcupLogsDir = ghcupBaseDir <&> (</> [rel|logs|])
-
-
 mkGhcupTmpDir :: (MonadThrow m, MonadIO m) => m (Path Abs)
 mkGhcupTmpDir = do
  tmpdir <- liftIO $ getEnvDefault "TMPDIR" "/tmp"
@@ -103,6 +189,8 @@ withGHCupTmpDir :: (MonadResource m, MonadThrow m, MonadIO m) => m (Path Abs)
 withGHCupTmpDir = snd <$> allocate mkGhcupTmpDir deleteDirRecursive


+
+
    --------------
    --[ Others ]--
    --------------
@@ -116,3 +204,23 @@ getHomeDirectory = do
    Nothing -> do
      h <- PU.homeDirectory <$> (PU.getEffectiveUserID >>= PU.getUserEntryForID)
      parseAbs $ UTF8.fromString h -- this is a guess
+
+
+useXDG :: IO Bool
+useXDG = isJust <$> getEnv "GHCUP_USE_XDG_DIRS"
+
+
+relativeSymlink :: Path Abs  -- ^ the path in which to create the symlink
+                -> Path Abs  -- ^ the symlink destination
+                -> ByteString
+relativeSymlink (toFilePath -> p1) (toFilePath -> p2) =
+  let d1      = splitDirectories p1
+      d2      = splitDirectories p2
+      common  = takeWhile (\(x, y) -> x == y) $ zip d1 d2
+      cPrefix = drop (length common) d1
+  in  joinPath (replicate (length cPrefix) "..")
+        <> joinPath ("/" : (drop (length common) d2))
+
+
+
+
--- a/lib/GHCup/Utils/File.hs
+++ b/lib/GHCup/Utils/File.hs
@@ -2,12 +2,13 @@
 {-# LANGUAGE OverloadedStrings #-}
 {-# LANGUAGE FlexibleContexts  #-}
 {-# LANGUAGE TemplateHaskell   #-}
+{-# LANGUAGE ViewPatterns      #-}

 {-|
 Module      : GHCup.Utils.File
 Description : File and unix APIs
 Copyright   : (c) Julian Ospald, 2020
-License     : GPL-3
+License     : LGPL-3.0
 Maintainer  : hasufell@hasufell.de
 Stability   : experimental
 Portability : POSIX
@@ -17,7 +18,6 @@ Some of these functions use sophisticated logging.
 -}
 module GHCup.Utils.File where

-import           GHCup.Utils.Dirs
 import           GHCup.Utils.Prelude
 import           GHCup.Types

@@ -26,6 +26,7 @@ import           Control.Concurrent.Async
 import           Control.Exception              ( evaluate )
 import           Control.Exception.Safe
 import           Control.Monad
+import           Control.Monad.Logger
 import           Control.Monad.Reader
 import           Control.Monad.Trans.State.Strict
 import           Data.ByteString                ( ByteString )
@@ -34,6 +35,7 @@ import           Data.Functor
 import           Data.IORef
 import           Data.Maybe
 import           Data.Sequence                  ( Seq, (|>) )
+import           Data.String.Interpolate
 import           Data.Text                      ( Text )
 import           Data.Void
 import           Data.Word8
@@ -47,6 +49,7 @@ import           System.IO.Error
 import           System.Posix.Directory.ByteString
 import           System.Posix.FD               as FD
 import           System.Posix.FilePath   hiding ( (</>) )
+import           System.Posix.Files.ByteString
 import           System.Posix.Foreign           ( oExcl )
 import "unix"    System.Posix.IO.ByteString
                                         hiding ( openFd )
@@ -69,14 +72,6 @@ import qualified "unix-bytestring" System.Posix.IO.ByteString
                                               as SPIB


-
-data ProcessError = NonZeroExit Int ByteString [ByteString]
-                  | PTerminated ByteString [ByteString]
-                  | PStopped ByteString [ByteString]
-                  | NoSuchPid ByteString [ByteString]
-                  deriving Show
-
-
 data CapturedProcess = CapturedProcess
  { _exitCode :: ExitCode
  , _stdOut   :: ByteString
@@ -118,31 +113,31 @@ execLogged :: (MonadReader Settings m, MonadIO m, MonadThrow m)
           => ByteString       -- ^ thing to execute
           -> Bool             -- ^ whether to search PATH for the thing
           -> [ByteString]     -- ^ args for the thing
-           -> Path Rel         -- ^ log filename
           -> Maybe (Path Abs) -- ^ optionally chdir into this
           -> Maybe [(ByteString, ByteString)] -- ^ optional environment
           -> m (Either ProcessError ())
-execLogged exe spath args lfile chdir env = do
-  Settings {..} <- ask
-  ldir          <- liftIO ghcupLogsDir
-  logfile       <- (ldir </>) <$> parseRel (toFilePath lfile <> ".log")
+execLogged exe spath args chdir env = do
+  Settings {dirs = Dirs {..}, ..} <- ask
+  logfile       <- (logsDir </>) <$> parseRel (lfile <> ".log")
  liftIO $ bracket (createFile (toFilePath logfile) newFilePerms)
                   closeFd
-                   (action verbose)
+                   (action verbose execCb)
 where
-  action verbose fd = do
+  lfile = fromMaybe exe $ BS.stripPrefix "./" exe
+
+  action verbose cb fd = do
    actionWithPipes $ \(stdoutRead, stdoutWrite) -> do
      -- start the thread that logs to stdout
-      pState <- newEmptyMVar
-      done   <- newEmptyMVar
+      pState  <- newEmptyMVar
+      done    <- newEmptyMVar
+      liftIO $ HPath.IO.writeFile [HPath.abs|/home/jule/git/ghcup-hs/cb.log|] Nothing "execLogged1"
      void
        $ forkIO
        $ EX.handle (\(_ :: IOException) -> pure ())
        $ flip EX.finally (putMVar done ())
-        $ (if verbose
-            then tee fd stdoutRead
-            else printToRegion fd stdoutRead 6 pState
-          )
+        $ (do
+            liftIO $ HPath.IO.writeFile [HPath.abs|/home/jule/git/ghcup-hs/cb.log|] Nothing "execLogged"
+            cb verbose fd stdoutRead pState lfile)

      -- fork the subprocess
      pid <- SPPB.forkProcess $ do
@@ -155,115 +150,57 @@ execLogged exe spath args lfile chdir env = do
        maybe (pure ()) (changeWorkingDirectory . toFilePath) chdir
        void $ SPPB.executeFile exe spath args env

+      putMVar pState (PRunning pid)
+
      closeFd stdoutWrite

      -- wait for the subprocess to finish
      e <- toProcessError exe args <$!> SPPB.getProcessStatus True True pid
-      putMVar pState (either (const False) (const True) e)
+      void $ swapMVar pState (PExited e)

      void $ race (takeMVar done) (threadDelay (1000000 * 3))
      closeFd stdoutRead

      pure e

-  tee :: Fd -> Fd -> IO ()
-  tee fileFd fdIn = readTilEOF lineAction fdIn

-   where
-    lineAction :: ByteString -> IO ()
-    lineAction bs' = do
-      void $ SPIB.fdWrite fileFd (bs' <> "\n")
-      void $ SPIB.fdWrite stdOutput (bs' <> "\n")
+readLineTilEOF :: MonadIO m => (ByteString -> m a) -> Fd -> m ()
+readLineTilEOF ~action' fd' = go mempty
+ where
+  go bs' = do
+    (bs, rest, eof) <- readLine fd' bs'
+    if eof
+       then liftIO $ ioError (mkIOError eofErrorType "" Nothing Nothing)
+       else (void $ action' bs) >> go rest

-  -- Reads fdIn and logs the output in a continous scrolling area
-  -- of 'size' terminal lines. Also writes to a log file.
-  printToRegion :: Fd -> Fd -> Int -> MVar Bool -> IO ()
-  printToRegion fileFd fdIn size pState = do
-    void $ displayConsoleRegions $ do
-      rs <-
-        liftIO
-        . fmap Sq.fromList
-        . sequence
-        . replicate size
-        . openConsoleRegion
-        $ Linear
-      flip runStateT mempty
-        $ handle
-            (\(ex :: SomeException) -> do
-              ps <- liftIO $ takeMVar pState
-              when (ps == True) (forM_ rs (liftIO . closeConsoleRegion))
-              throw ex
-            )
-        $ readTilEOF (lineAction rs) fdIn

-   where
-    -- action to perform line by line
-    -- TODO: do this with vty for efficiency
-    lineAction :: (MonadMask m, MonadIO m)
-               => Seq ConsoleRegion
-               -> ByteString
-               -> StateT (Seq ByteString) m ()
-    lineAction rs = \bs' -> do
-      void $ liftIO $ SPIB.fdWrite fileFd (bs' <> "\n")
-      modify (swapRegs bs')
-      regs <- get
-      liftIO $ forM_ (Sq.zip regs rs) $ \(bs, r) -> setConsoleRegion r $ do
-        w <- consoleWidth
-        return
-          . T.pack
-          . color Blue
-          . T.unpack
-          . decUTF8Safe
-          . trim w
-          . (\b -> "[ " <> toFilePath lfile <> " ] " <> b)
-          $ bs
+-- Consecutively read from Fd in 512 chunks until we hit
+-- newline or EOF.
+readLine :: MonadIO m
+         => Fd          -- ^ input file descriptor
+         -> ByteString  -- ^ rest buffer (read across newline)
+         -> m (ByteString, ByteString, Bool) -- ^ (full line, rest, eof)
+readLine fd = \inBs -> go inBs
+ where
+  go inBs = do
+    -- if buffer is not empty, process it first
+    mbs <- if BS.length inBs == 0
+             -- otherwise attempt read
+             then liftIO
+                  $ handleIO (\e -> if isEOFError e then pure Nothing else ioError e)
+                  $ fmap Just
+                  $ SPIB.fdRead fd 512
+             else pure $ Just inBs
+    case mbs of
+      Nothing -> pure ("", "", True)
+      Just bs -> do
+        -- split on newline
+        let (line, rest) = BS.span (/= _lf) bs
+        if
+          | BS.length rest /= 0 -> pure (line, BS.tail rest, False)
+          -- if rest is empty, then there was no newline, process further
+          | otherwise           -> (\(l, r, b) -> (line <> l, r, b)) <$!> go mempty

-    swapRegs :: a -> Seq a -> Seq a
-    swapRegs bs = \regs -> if
-      | Sq.length regs < size -> regs |> bs
-      | otherwise             -> Sq.drop 1 regs |> bs
-
-    -- trim output line to terminal width
-    trim :: Int -> ByteString -> ByteString
-    trim w = \bs -> if
-      | BS.length bs > w && w > 5 -> BS.take (w - 4) bs <> "..."
-      | otherwise                 -> bs
-
-  -- Consecutively read from Fd in 512 chunks until we hit
-  -- newline or EOF.
-  readLine :: MonadIO m
-           => Fd          -- ^ input file descriptor
-           -> ByteString  -- ^ rest buffer (read across newline)
-           -> m (ByteString, ByteString, Bool) -- ^ (full line, rest, eof)
-  readLine fd = \inBs -> go inBs
-   where
-    go inBs = do
-      -- if buffer is not empty, process it first
-      mbs <- if BS.length inBs == 0
-               -- otherwise attempt read
-               then liftIO
-                    $ handleIO (\e -> if isEOFError e then pure Nothing else ioError e)
-                    $ fmap Just
-                    $ SPIB.fdRead fd 512
-               else pure $ Just inBs
-      case mbs of
-        Nothing -> pure ("", "", True)
-        Just bs -> do
-          -- split on newline
-          let (line, rest) = BS.span (/= _lf) bs
-          if
-            | BS.length rest /= 0 -> pure (line, BS.tail rest, False)
-            -- if rest is empty, then there was no newline, process further
-            | otherwise           -> (\(l, r, b) -> (line <> l, r, b)) <$!> go mempty
-
-  readTilEOF :: MonadIO m => (ByteString -> m a) -> Fd -> m ()
-  readTilEOF ~action' fd' = go mempty
-   where
-    go bs' = do
-      (bs, rest, eof) <- readLine fd' bs'
-      if eof
-         then liftIO $ ioError (mkIOError eofErrorType "" Nothing Nothing)
-         else (void $ action' bs) >> go rest


 -- | Capture the stdout and stderr of the given action, which
@@ -377,7 +314,7 @@ toProcessError :: ByteString
               -> Maybe ProcessStatus
               -> Either ProcessError ()
 toProcessError exe args mps = case mps of
-  Just (SPPB.Exited (ExitFailure i)) -> Left $ NonZeroExit i exe args
+  Just (SPPB.Exited (ExitFailure xi)) -> Left $ NonZeroExit xi exe args
  Just (SPPB.Exited ExitSuccess    ) -> Right ()
  Just (Terminated _ _             ) -> Left $ PTerminated exe args
  Just (Stopped _                  ) -> Left $ PStopped exe args
@@ -427,3 +364,97 @@ findFiles' path parser = do
                             Right p' -> isJust $ MP.parseMaybe parser p')
    $ dirContentsStream dirStream
  pure $ join $ fmap parseRel f
+
+
+isBrokenSymlink :: Path Abs -> IO Bool
+isBrokenSymlink p =
+  handleIO
+      (\e -> if ioeGetErrorType e == NoSuchThing then pure True else throwIO e)
+    $ do
+        _ <- canonicalizePath p
+        pure False
+
+
+chmod_777 :: (MonadLogger m, MonadIO m) => Path a -> m ()
+chmod_777 (toFilePath -> fp) = do
+  let exe_mode =
+          newFilePerms
+            `unionFileModes` ownerExecuteMode
+            `unionFileModes` groupExecuteMode
+            `unionFileModes` otherExecuteMode
+  $(logDebug) [i|chmod 777 #{fp}|]
+  liftIO $ setFileMode fp exe_mode
+
+
+-- | The default callback for logging/printing on 'execLogged'.
+defExecCb :: ExecCb
+defExecCb verbose fd stdoutRead pState lfile = if verbose
+      then tee fd stdoutRead
+      else printToRegion fd stdoutRead 6
+ where
+  tee :: Fd -> Fd -> IO ()
+  tee fileFd fdIn = readLineTilEOF lineAction fdIn
+
+   where
+    lineAction :: ByteString -> IO ()
+    lineAction bs' = do
+      void $ SPIB.fdWrite fileFd (bs' <> "\n")
+      void $ SPIB.fdWrite stdOutput (bs' <> "\n")
+
+  -- Reads fdIn and logs the output in a continous scrolling area
+  -- of 'size' terminal lines. Also writes to a log file.
+  printToRegion :: Fd -> Fd -> Int -> IO ()
+  printToRegion fileFd fdIn size = do
+    void $ displayConsoleRegions $ do
+      rs <-
+        liftIO
+        . fmap Sq.fromList
+        . sequence
+        . replicate size
+        . openConsoleRegion
+        $ Linear
+      flip runStateT mempty
+        $ handle
+            (\(ex :: SomeException) -> do
+              let closeEventually = readMVar pState >>= \case
+                    PExited (Right _) -> forM_ rs (liftIO . closeConsoleRegion)
+                    _ -> threadDelay 500 >> closeEventually
+              void $ liftIO $ race closeEventually (threadDelay (1000000 * 3))
+              throw ex
+            )
+        $ readLineTilEOF (lineAction rs) fdIn
+
+   where
+    -- action to perform line by line
+    -- TODO: do this with vty for efficiency
+    lineAction :: (MonadMask m, MonadIO m)
+               => Seq ConsoleRegion
+               -> ByteString
+               -> StateT (Seq ByteString) m ()
+    lineAction rs = \bs' -> do
+      void $ liftIO $ SPIB.fdWrite fileFd (bs' <> "\n")
+      modify (swapRegs bs')
+      regs <- get
+      liftIO $ forM_ (Sq.zip regs rs) $ \(bs, r) -> setConsoleRegion r $ do
+        w <- consoleWidth
+        return
+          . T.pack
+          . color Blue
+          . T.unpack
+          . decUTF8Safe
+          . trim w
+          . (\b -> "[ " <> lfile <> " ] " <> b)
+          $ bs
+
+    swapRegs :: a -> Seq a -> Seq a
+    swapRegs bs = \regs -> if
+      | Sq.length regs < size -> regs |> bs
+      | otherwise             -> Sq.drop 1 regs |> bs
+
+    -- trim output line to terminal width
+    trim :: Int -> ByteString -> ByteString
+    trim w = \bs -> if
+      | BS.length bs > w && w > 5 -> BS.take (w - 4) bs <> "..."
+      | otherwise                 -> bs
+
+
--- a/lib/GHCup/Utils/Logger.hs
+++ b/lib/GHCup/Utils/Logger.hs
@@ -1,10 +1,11 @@
 {-# LANGUAGE QuasiQuotes           #-}
+{-# LANGUAGE FlexibleContexts      #-}

 {-|
 Module      : GHCup.Utils.Logger
 Description : logger definition
 Copyright   : (c) Julian Ospald, 2020
-License     : GPL-3
+License     : LGPL-3.0
 Maintainer  : hasufell@hasufell.de
 Stability   : experimental
 Portability : POSIX
@@ -13,9 +14,11 @@ Here we define our main logger.
 -}
 module GHCup.Utils.Logger where

-import           GHCup.Utils
+import           GHCup.Types

 import           Control.Monad
+import           Control.Monad.IO.Class
+import           Control.Monad.Reader
 import           Control.Monad.Logger
 import           HPath
 import           HPath.IO
@@ -61,11 +64,12 @@ myLoggerT LoggerConfig {..} loggingt = runLoggingT loggingt mylogger
    rawOutter outr


-initGHCupFileLogging :: Path Rel -> IO (Path Abs)
+initGHCupFileLogging :: (MonadIO m, MonadReader Settings m) => Path Rel -> m (Path Abs)
 initGHCupFileLogging context = do
-  logs <- ghcupLogsDir
-  let logfile = logs </> context
-  createDirIfMissing newDirPerms logs
-  hideError doesNotExistErrorType $ deleteFile logfile
-  createRegularFile newFilePerms logfile
-  pure logfile
+  Settings {dirs = Dirs {..}} <- ask
+  let logfile = logsDir </> context
+  liftIO $ do
+    createDirRecursive newDirPerms logsDir
+    hideError doesNotExistErrorType $ deleteFile logfile
+    createRegularFile newFilePerms logfile
+    pure logfile
--- a/lib/GHCup/Utils/MegaParsec.hs
+++ b/lib/GHCup/Utils/MegaParsec.hs
@@ -5,7 +5,7 @@
 Module      : GHCup.Utils.MegaParsec
 Description : MegaParsec utilities
 Copyright   : (c) Julian Ospald, 2020
-License     : GPL-3
+License     : LGPL-3.0
 Maintainer  : hasufell@hasufell.de
 Stability   : experimental
 Portability : POSIX
--- a/lib/GHCup/Utils/Prelude.hs
+++ b/lib/GHCup/Utils/Prelude.hs
@@ -12,7 +12,7 @@
 Module      : GHCup.Utils.Prelude
 Description : MegaParsec utilities
 Copyright   : (c) Julian Ospald, 2020
-License     : GPL-3
+License     : LGPL-3.0
 Maintainer  : hasufell@hasufell.de
 Stability   : experimental
 Portability : POSIX
--- a/lib/GHCup/Utils/String/QQ.hs
+++ b/lib/GHCup/Utils/String/QQ.hs
@@ -4,7 +4,7 @@
 Module      : GHCup.Utils.String.QQ
 Description : String quasi quoters
 Copyright   : (c) Audrey Tang <audreyt@audreyt.org> 2019, Julian Ospald <hasufell@posteo.de> 2020
-License     : GPL-3
+License     : LGPL-3.0
 Maintainer  : hasufell@hasufell.de
 Stability   : experimental
 Portability : POSIX
--- a/lib/GHCup/Utils/Version/QQ.hs
+++ b/lib/GHCup/Utils/Version/QQ.hs
@@ -11,7 +11,7 @@
 Module      : GHCup.Utils.Version.QQ
 Description : Version quasi-quoters
 Copyright   : (c) Julian Ospald, 2020
-License     : GPL-3
+License     : LGPL-3.0
 Maintainer  : hasufell@hasufell.de
 Stability   : experimental
 Portability : POSIX
--- a/lib/GHCup/Version.hs
+++ b/lib/GHCup/Version.hs
@@ -5,7 +5,7 @@
 Module      : GHCup.Version
 Description : Static version information
 Copyright   : (c) Julian Ospald, 2020
-License     : GPL-3
+License     : LGPL-3.0
 Maintainer  : hasufell@hasufell.de
 Stability   : experimental
 Portability : POSIX
@@ -20,13 +20,13 @@ import           URI.ByteString.QQ

 import qualified Data.Text                     as T

-- | This reflects the API version of the JSON.
+-- | This reflects the API version of the YAML.
 ghcupURL :: URI
-ghcupURL = [uri|https://www.haskell.org/ghcup/data/ghcup-0.0.2.json|]
+ghcupURL = [uri|https://www.haskell.org/ghcup/data/ghcup-0.0.2.yaml|]

-- | The curren ghcup version.
+-- | The current ghcup version.
 ghcUpVer :: PVP
-ghcUpVer = [pver|0.1.8|]
+ghcUpVer = [pver|0.1.10|]

 -- | ghcup version as numeric string.
 numericVer :: String
Author	SHA1	Message	Date
Julian Ospald	14168a41fe	Lala	2020-08-27 23:39:47 +02:00
Julian Ospald	6342e8edf0	Use 8.10.2 in gitlab CI	2020-08-15 23:54:50 +02:00
Julian Ospald	bbd8f0c84c	Add GHC-8.10.2 for alpine 32big	2020-08-15 23:34:05 +02:00
Julian Ospald	873c951d6e	Refactor chmod +x	2020-08-14 22:27:05 +02:00
Julian Ospald	d9c864d3c5	Make sure cabal is executable wrt #46	2020-08-14 22:07:39 +02:00
Julian Ospald	4280d7109a	Fix 3.4.0.0-rc1 urls wrt #46	2020-08-14 21:49:01 +02:00
Julian Ospald	c8855c068f	Update version in bootstrap-haskell	2020-08-14 20:36:14 +02:00
Julian Ospald	90503061e9	Add ghcup-0.1.10	2020-08-14 20:22:27 +02:00
Julian Ospald	672ebf6426	Bump version	2020-08-14 16:57:15 +02:00
Julian Ospald	fd76fde23a	Add cabal-3.4.0.0-rc1	2020-08-14 16:54:27 +02:00
Julian Ospald	e24c9a3ffe	Show stray cabals, fixes #45	2020-08-14 16:53:32 +02:00
Julian Ospald	2641d50c21	Update ghcup binaries	2020-08-14 09:42:41 +02:00
Julian Ospald	202f3ea3ba	Fix bug where setting non-installed GHC unsets current one	2020-08-13 20:40:09 +02:00
Julian Ospald	4f09e3ff7e	Update CHANGELOG	2020-08-13 17:01:09 +02:00
Julian Ospald	1148219130	Fix README	2020-08-12 10:13:18 +02:00
Julian Ospald	4b47800dfb	CHANGELOG fix	2020-08-11 22:38:22 +02:00
Julian Ospald	e2c4db9132	Rm unneeded note	2020-08-11 22:04:08 +02:00
Julian Ospald	90af68b211	Pre-release 0.1.9	2020-08-11 21:55:15 +02:00
Julian Ospald	80603662b4	Merge branch 'cabal-install-3.4.0.0-rc1'	2020-08-11 21:34:45 +02:00
Julian Ospald	d2c5d4dfd9	Test that we're not missing GHCup alpine	2020-08-11 20:23:15 +02:00
Julian Ospald	6f1b8b4041	Fix build on 32bit	2020-08-11 19:47:29 +02:00
Julian Ospald	f63b2bf744	Fix CI	2020-08-11 11:48:42 +02:00
Julian Ospald	71cb75c170	Update .gitignore	2020-08-10 22:28:02 +02:00
Julian Ospald	dac64f5718	Make TarDir backwardscompat	2020-08-10 22:28:02 +02:00
Julian Ospald	27b2d2ac7d	Fix cabal.project for cabal-3.4	2020-08-10 22:28:01 +02:00
Julian Ospald	47142dd376	Test on 32bit	2020-08-10 22:28:01 +02:00
Julian Ospald	d071a7e51b	Avoid duplicate edits to .bashrc etc	2020-08-10 22:28:01 +02:00
Julian Ospald	5c45884f5f	Allow to specify regex for subdir	2020-08-10 22:27:50 +02:00
Julian Ospald	cafedd73a2	Use Settings to avoid querying dirs every time	2020-08-10 21:52:30 +02:00
Julian Ospald	7163b77837	Only query directories once	2020-08-10 21:51:31 +02:00
Julian Ospald	122c54b51e	Refactor	2020-08-10 21:51:31 +02:00
Julian Ospald	b9d7d7d007	Fix licences in module haddock	2020-08-10 21:51:29 +02:00
Julian Ospald	9050c9792a	Improve bootstrap-haskell	2020-08-10 21:51:20 +02:00
Julian Ospald	aac8f760ad	Add xdg support wrt #39	2020-08-10 21:51:19 +02:00
Julian Ospald	7d334c18f5	Don't stop TUI on subcommand failure	2020-08-10 21:51:19 +02:00
Julian Ospald	86b0e4b31b	Fix `cabalSet` for pre-release versions	2020-08-10 21:51:19 +02:00
Julian Ospald	af811f3dbc	`nub` result in getInstalledCabals	2020-08-10 21:51:19 +02:00
Julian Ospald	d30d2ac8a5	Add cabal-install-3.4.0.0-rc1	2020-08-10 21:51:00 +02:00
Julian Ospald	86a4b10de6	Merge branch 'yaml'	2020-08-10 08:58:55 +02:00
Julian Ospald	cfa7049ab9	Merge branch 'CI'	2020-08-09 22:11:48 +02:00
Julian Ospald	391676e90a	Use yaml instead of pesky json	2020-08-09 21:56:11 +02:00
Julian Ospald	a046f16308	Remove libtinfo compat symlinks	2020-07-21 00:36:31 +02:00