GHC new build system megapatch

[ghc-hetmet.git] / utils / runghc / runghc.hs

diff --git a/utils/runghc/runghc.hs b/utils/runghc/runghc.hs
index 5053858..aadafd9 100644 (file)
--- a/utils/runghc/runghc.hs
+++ b/utils/runghc/runghc.hs
@@ -25,6 +25,8 @@ module Main (main) where
 import Control.Exception
 import Data.Char
 import Data.List
+import Data.Monoid
+import Data.Version
 import System.Cmd
 import System.Directory
 import System.Environment
@@ -32,12 +34,20 @@ import System.Exit
 import System.FilePath
 import System.IO
 
+#if defined(mingw32_HOST_OS)
+import Control.Monad
+import Foreign
+import Foreign.C.String
+#endif
+
 main :: IO ()
 main = do
     args <- getArgs
-    case getGhcLoc args of
-        (Just ghc, args') -> doIt ghc args'
-        (Nothing, args') -> do
+    case parseRunGhcFlags args of
+        (Help, _) -> printUsage
+        (ShowVersion, _) -> printVersion
+        (RunGhcFlags (Just ghc), args') -> doIt ghc args'
+        (RunGhcFlags Nothing, args') -> do
             mbPath <- getExecPath
             case mbPath of
                 Nothing  -> dieProg ("cannot find ghc")
@@ -45,20 +55,44 @@ main = do
                     let ghc = takeDirectory (normalise path) </> "ghc"
                     in doIt ghc args'
 
-getGhcLoc :: [String] -> (Maybe FilePath, [String])
-getGhcLoc args = case args of
-                 "-f" : ghc : args' -> f ghc args'
-                 ('-' : 'f' : ghc) : args' -> f ghc args'
-                 -- If you need the first GHC flag to be a -f flag then
-                 -- you can pass -- first
-                 "--" : args -> (Nothing, args)
-                 args        -> (Nothing, args)
-    where f ghc args' = -- If there is another -f flag later on then
-                        -- that overrules the one that we've already
-                        -- found
-                        case getGhcLoc args' of
-                        (Nothing, _) -> (Just ghc, args')
-                        success -> success
+data RunGhcFlags = RunGhcFlags (Maybe FilePath) -- GHC location
+                 | Help -- Print help text
+                 | ShowVersion -- Print version info
+
+instance Monoid RunGhcFlags where
+    mempty = RunGhcFlags Nothing
+    Help `mappend` _ = Help
+    _ `mappend` Help = Help
+    ShowVersion `mappend` _ = ShowVersion
+    _ `mappend` ShowVersion = ShowVersion
+    RunGhcFlags _ `mappend` right@(RunGhcFlags (Just _)) = right
+    left@(RunGhcFlags _) `mappend` RunGhcFlags Nothing = left
+
+parseRunGhcFlags :: [String] -> (RunGhcFlags, [String])
+parseRunGhcFlags = f mempty
+    where f flags ("-f" : ghc : args)
+              = f (flags `mappend` RunGhcFlags (Just ghc)) args
+          f flags (('-' : 'f' : ghc) : args)
+              = f (flags `mappend` RunGhcFlags (Just ghc)) args
+          f flags ("--help" : args) = f (flags `mappend` Help) args
+          f flags ("--version" : args) = f (flags `mappend` ShowVersion) args
+          -- If you need the first GHC flag to be a -f flag then
+          -- you can pass -- first
+          f flags ("--" : args) = (flags, args)
+          f flags         args  = (flags, args)
+
+printVersion :: IO ()
+printVersion = do
+    putStrLn ("runghc " ++ VERSION)
+
+printUsage :: IO ()
+printUsage = do
+    putStrLn "Usage: runghc [runghc flags] [GHC flags] module [program args]"
+    putStrLn ""
+    putStrLn "The runghc flags are"
+    putStrLn "    -f /path/to/ghc       Tell runghc where GHC is"
+    putStrLn "    --help                Print this usage information"
+    putStrLn "    --version             Print version number"
 
 doIt :: String -> [String] -> IO ()
 doIt ghc args = do
@@ -70,15 +104,22 @@ doIt ghc args = do
            tmpdir <- getTemporaryDirectory
            bracket
              (openTempFile tmpdir "runghcXXXX.hs")
-             (\(filename,_) -> removeFile filename)
+             (\(filename,h) -> do hClose h; removeFile filename)
              $ \(filename,h) -> do
                  getContents >>= hPutStr h
                  hClose h
                  doIt ghc (ghc_args ++ [filename])
         filename : prog_args -> do
-            let xflag = if takeExtension filename == ".lhs"
-                        then []
-                        else ["-x", "hs"]
+            -- If the file exists, and is not a .lhs file, then we
+            -- want to treat it as a .hs file.
+            --
+            -- If the file doesn't exist then GHC is going to look for
+            -- filename.hs and filename.lhs, and use the appropriate
+            -- type.
+            exists <- doesFileExist filename
+            let xflag = if exists && (takeExtension filename /= ".lhs")
+                        then ["-x", "hs"]
+                        else []
                 c1 = ":set prog " ++ show filename
                 c2 = ":main " ++ show prog_args
             res <- rawSystem ghc (["-ignore-dot-ghci"] ++