taking over changes for IO module

see branch gui

src/lib/ExternalFunctionsIO.hs

@@ -3,7 +3,9 @@ module ExternalFunctionsIO where
 import Curry
 import CurryPrelude
 import InstancesIO
+
 import qualified System.IO as SI
+import Control.Concurrent
 
 instance ConvertCH C_IOMode SI.IOMode where
   toCurry SI.ReadMode = C_ReadMode
@@ -50,6 +52,22 @@ prim_hSeek = ioFunc3 SI.hSeek
 prim_hWaitForInput ::  C_Handle -> C_Int -> Result (C_IO C_Bool)
 prim_hWaitForInput = ioFunc2 SI.hWaitForInput
 
+selectHandle :: [SI.Handle] -> Int -> IO Int
+selectHandle handles t = do
+  mvar <- newEmptyMVar
+  threads <- mapM (\ (i,h) -> forkIO (waitOnHandle h i t mvar)) (zip [0..] handles)
+  res <- readMVar mvar
+  mapM_ killThread threads
+  return (maybe (-1) id res)
+
+waitOnHandle :: SI.Handle -> Int -> Int -> MVar (Maybe Int) -> IO ()
+waitOnHandle h v t mvar = do
+  ready <- SI.hWaitForInput h t
+  putMVar mvar (if ready then Just v else Nothing)
+
+prim_hWaitForInputs :: List C_Handle -> C_Int -> Result (C_IO C_Int)
+prim_hWaitForInputs  = ioFunc2 selectHandle
+
 prim_hGetChar :: C_Handle -> Result (C_IO C_Char)
 prim_hGetChar = ioFunc1 SI.hGetChar
 

src/lib/IO.curry

@@ -3,16 +3,17 @@
 --- that are not already contained in the prelude.
 ---
 --- @author Michael Hanus, Bernd Braßel
---- @version April 2006
+--- @version June 2006
 -----------------------------------------------------------------------------
 
 module IO(Handle,IOMode(..),SeekMode(..),stdin,stdout,stderr,
           openFile,hClose,hFlush,hIsEOF,isEOF,
-          hSeek,hWaitForInput,hReady,
+          hSeek,hWaitForInput,hWaitForInputs,hReady, 
           hGetChar,hGetLine,hGetContents,getContents,
           hPutChar,hPutStr,hPutStrLn,hPrint,
           hIsReadable,hIsWritable) where
 
+--- The abstract type of a handle for a stream.
 data Handle -- internally defined
 
 --- The modes for opening a file.
@@ -21,6 +22,7 @@ data IOMode = ReadMode | WriteMode | AppendMode
 --- The modes for positioning with <code>hSeek</code> in a file.
 data SeekMode = AbsoluteSeek | RelativeSeek | SeekFromEnd
 
+
 --- Standard input stream.
 stdin :: Handle
 stdin external
@@ -35,7 +37,7 @@ stderr external
 
 --- Opens a file in specified mode and returns a handle to it.
 openFile :: String -> IOMode -> IO Handle
-openFile fileName mode =  (prim_openFile $## fileName) $# mode
+openFile filename mode = (prim_openFile $## filename) $# mode
 
 prim_openFile :: String -> IOMode -> IO Handle
 prim_openFile external
@@ -65,6 +67,7 @@ prim_hIsEOF external
 isEOF :: IO Bool
 isEOF = hIsEOF stdin
 
+
 --- Set the position of a handle to a seekable stream (e.g., a file).
 --- If the second argument is <code>AbsoluteSeek</code>,
 --- <code>SeekFromEnd</code>, or <code>RelativeSeek</code>,
@@ -89,6 +92,20 @@ hWaitForInput h i = (prim_hWaitForInput $# h)  $# i
 prim_hWaitForInput :: Handle -> Int -> IO Bool
 prim_hWaitForInput external
 
+--- Waits until input is available on some of the given handles.
+--- If no input is available within t milliseconds, it returns -1,
+--- otherwise it returns the index of the corresponding handle with the available
+--- data.
+--- @param handles - a list of handles for input streams
+--- @param timeout - milliseconds to wait for input (< 0 : no time out)
+--- @return -1 if no input is available within the time out, otherwise i
+---         if (handles!!i) has data available
+hWaitForInputs :: [Handle] -> Int -> IO Int
+hWaitForInputs handles timeout =
+   (prim_hWaitForInputs $## handles) $# timeout
+
+prim_hWaitForInputs :: [Handle] -> Int -> IO Int
+prim_hWaitForInputs external
 
 --- Checks whether an input is available on a given handle.
 hReady :: Handle -> IO Bool