[project @ 2005-03-02 13:11:00 by simonmar]

[ghc-base.git] / GHC / Conc.lhs

diff --git a/GHC/Conc.lhs b/GHC/Conc.lhs
index 3c69c22..8476498 100644 (file)
--- a/GHC/Conc.lhs
+++ b/GHC/Conc.lhs
@@ -1,5 +1,5 @@
 \begin{code}
-{-# OPTIONS -fno-implicit-prelude #-}
+{-# OPTIONS_GHC -fno-implicit-prelude #-}
 -----------------------------------------------------------------------------
 -- |
 -- Module      :  GHC.Conc
@@ -14,7 +14,12 @@
 -- 
 -----------------------------------------------------------------------------
 
-#include "ghcconfig.h"
+-- No: #hide, because bits of this module are exposed by the stm package.
+-- However, we don't want this module to be the home location for the
+-- bits it exports, we'd rather have Control.Concurrent and the other
+-- higher level modules be the home.  Hence:
+
+-- #not-home
 module GHC.Conc
        ( ThreadId(..)
 
@@ -55,7 +60,7 @@ module GHC.Conc
        , writeTVar     -- :: a -> TVar a -> STM ()
        , unsafeIOToSTM -- :: IO a -> STM a
 
-#ifdef mingw32_TARGET_OS
+#ifdef mingw32_HOST_OS
        , asyncRead     -- :: Int -> Int -> Int -> Ptr a -> IO (Int, Int)
        , asyncWrite    -- :: Int -> Int -> Int -> Ptr a -> IO (Int, Int)
        , asyncDoProc   -- :: FunPtr (Ptr a -> IO Int) -> Ptr a -> IO Int
@@ -81,6 +86,7 @@ import GHC.Exception    ( Exception(..), AsyncException(..) )
 import GHC.Pack                ( packCString# )
 import GHC.Ptr          ( Ptr(..), plusPtr, FunPtr(..) )
 import GHC.STRef
+import Data.Typeable
 
 infixr 0 `par`, `pseq`
 \end{code}
@@ -92,7 +98,7 @@ infixr 0 `par`, `pseq`
 %************************************************************************
 
 \begin{code}
-data ThreadId = ThreadId ThreadId#
+data ThreadId = ThreadId ThreadId# deriving( Typeable )
 -- ToDo: data ThreadId = ThreadId (Weak ThreadId#)
 -- But since ThreadId# is unlifted, the Weak type must use open
 -- type variables.
@@ -202,7 +208,7 @@ TVars are shared memory locations which support atomic memory
 transactions.
 
 \begin{code}
-newtype STM a = STM (State# RealWorld -> (# State# RealWorld, a #))
+newtype STM a = STM (State# RealWorld -> (# State# RealWorld, a #)) deriving( Typeable )
 
 unSTM :: STM a -> (State# RealWorld -> (# State# RealWorld, a #))
 unSTM (STM a) = a
@@ -260,7 +266,7 @@ orElse (STM m) e = STM $ \s -> catchRetry# m (unSTM e) s
 catchSTM :: STM a -> (Exception -> STM a) -> STM a
 catchSTM (STM m) k = STM $ \s -> catchSTM# m (\ex -> unSTM (k ex)) s
 
-data TVar a = TVar (TVar# RealWorld a)
+data TVar a = TVar (TVar# RealWorld a) deriving( Typeable )
 
 instance Eq (TVar a) where
        (TVar tvar1#) == (TVar tvar2#) = sameTVar# tvar1# tvar2#
@@ -377,25 +383,20 @@ addMVarFinalizer (MVar m) finalizer =
 %************************************************************************
 
 \begin{code}
-#ifdef mingw32_TARGET_OS
+#ifdef mingw32_HOST_OS
 
 -- Note: threadDelay, threadWaitRead and threadWaitWrite aren't really functional
 -- on Win32, but left in there because lib code (still) uses them (the manner
 -- in which they're used doesn't cause problems on a Win32 platform though.)
 
 asyncRead :: Int -> Int -> Int -> Ptr a -> IO (Int, Int)
-asyncRead  (I# fd) (I# isSock) (I# len) (Ptr buf) = do
-  (l, rc) <- IO (\s -> case asyncRead# fd isSock len buf s  of 
-                        (# s, len#, err# #) -> (# s, (I# len#, I# err#) #))
-    -- special handling for Ctrl+C-aborted 'standard input' reads;
-    -- see rts/win32/ConsoleHandler.c for details.
-  if (l == 0 && rc == -2)
-   then asyncRead (I# fd) (I# isSock) (I# len) (Ptr buf)
-   else return (l,rc)
+asyncRead  (I# fd) (I# isSock) (I# len) (Ptr buf) =
+  IO $ \s -> case asyncRead# fd isSock len buf s of 
+              (# s, len#, err# #) -> (# s, (I# len#, I# err#) #)
 
 asyncWrite :: Int -> Int -> Int -> Ptr a -> IO (Int, Int)
-asyncWrite  (I# fd) (I# isSock) (I# len) (Ptr buf) = 
-  IO $ \s -> case asyncWrite# fd isSock len buf s  of 
+asyncWrite  (I# fd) (I# isSock) (I# len) (Ptr buf) =
+  IO $ \s -> case asyncWrite# fd isSock len buf s of 
               (# s, len#, err# #) -> (# s, (I# len#, I# err#) #)
 
 asyncDoProc :: FunPtr (Ptr a -> IO Int) -> Ptr a -> IO Int
@@ -426,7 +427,7 @@ asyncWriteBA fd isSock len off bufB =
 -- given file descriptor (GHC only).
 threadWaitRead :: Fd -> IO ()
 threadWaitRead fd
-#ifndef mingw32_TARGET_OS
+#ifndef mingw32_HOST_OS
   | threaded  = waitForReadEvent fd
 #endif
   | otherwise = IO $ \s -> 
@@ -438,7 +439,7 @@ threadWaitRead fd
 -- given file descriptor (GHC only).
 threadWaitWrite :: Fd -> IO ()
 threadWaitWrite fd
-#ifndef mingw32_TARGET_OS
+#ifndef mingw32_HOST_OS
   | threaded  = waitForWriteEvent fd
 #endif
   | otherwise = IO $ \s -> 
@@ -459,7 +460,7 @@ threadWaitWrite fd
 --
 threadDelay :: Int -> IO ()
 threadDelay time
-#ifndef mingw32_TARGET_OS
+#ifndef mingw32_HOST_OS
   | threaded  = waitForDelayEvent time
 #else
   | threaded  = c_Sleep (fromIntegral (time `quot` 1000))
@@ -470,7 +471,7 @@ threadDelay time
        }}
 
 -- On Windows, we just make a safe call to 'Sleep' to implement threadDelay.
-#ifdef mingw32_TARGET_OS
+#ifdef mingw32_HOST_OS
 foreign import ccall safe "Sleep" c_Sleep :: CInt -> IO ()
 #endif
 
@@ -508,7 +509,7 @@ foreign import ccall unsafe "rtsSupportsBoundThreads" threaded :: Bool
 --     - forkProcess will kill the IO manager thread.  Let's just
 --       hope we don't need to do any blocking IO between fork & exec.
 
-#ifndef mingw32_TARGET_OS
+#ifndef mingw32_HOST_OS
 
 data IOReq
   = Read   {-# UNPACK #-} !Fd {-# UNPACK #-} !(MVar ())
@@ -572,24 +573,26 @@ service_loop wakeup readfds writefds ptimeval old_reqs old_delays = do
   fdSet wakeup readfds
   maxfd <- buildFdSets 0 readfds writefds reqs
 
-  -- check the current time and wake up any thread in threadDelay whose
-  -- timeout has expired.  Also find the timeout value for the select() call.
-  now <- getTicksOfDay
-  (delays', timeout) <- getDelay now ptimeval delays
-
   -- perform the select()
-  let do_select = do
+  let do_select delays = do
+         -- check the current time and wake up any thread in
+         -- threadDelay whose timeout has expired.  Also find the
+         -- timeout value for the select() call.
+         now <- getTicksOfDay
+         (delays', timeout) <- getDelay now ptimeval delays
+
          res <- c_select ((max wakeup maxfd)+1) readfds writefds 
                        nullPtr timeout
          if (res == -1)
             then do
                err <- getErrno
                if err == eINTR
-                       then do_select
-                       else return res
+                       then do_select delays'
+                       else return (res,delays')
             else
-               return res
-  res <- do_select
+               return (res,delays')
+
+  (res,delays') <- do_select delays
   -- ToDo: check result
 
   b <- takeMVar prodding