-----------------------------------------------------------------------------
-- 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(..)
, asyncReadBA -- :: Int -> Int -> Int -> Int -> MutableByteArray# RealWorld -> IO (Int, Int)
, asyncWriteBA -- :: Int -> Int -> Int -> Int -> MutableByteArray# RealWorld -> IO (Int, Int)
#endif
+
+#ifndef mingw32_HOST_OS
+ , ensureIOManagerIsRunning
+#endif
) where
import System.Posix.Types
{-# NOINLINE pendingEvents #-}
{-# NOINLINE pendingDelays #-}
(pendingEvents,pendingDelays) = unsafePerformIO $ do
- startIOServiceThread
+ startIOManagerThread
reqs <- newIORef []
dels <- newIORef []
return (reqs, dels)
-- the first time we schedule an IO request, the service thread
-- will be created (cool, huh?)
-startIOServiceThread :: IO ()
-startIOServiceThread = do
+ensureIOManagerIsRunning :: IO ()
+ensureIOManagerIsRunning
+ | threaded = seq pendingEvents $ return ()
+ | otherwise = return ()
+
+startIOManagerThread :: IO ()
+startIOManagerThread = do
allocaArray 2 $ \fds -> do
- throwErrnoIfMinus1 "startIOServiceThread" (c_pipe fds)
+ throwErrnoIfMinus1 "startIOManagerThread" (c_pipe fds)
rd_end <- peekElemOff fds 0
wr_end <- peekElemOff fds 1
writeIORef stick (fromIntegral wr_end)
+ c_setIOManagerPipe wr_end
quickForkIO $ do
allocaBytes sizeofFdSet $ \readfds -> do
allocaBytes sizeofFdSet $ \writefds -> 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
- if b then alloca $ \p -> do c_read (fromIntegral wakeup) p 1; return ()
- else return ()
+ b <- fdIsSet wakeup readfds
+ if b == 0
+ then return ()
+ else alloca $ \p -> do
+ c_read (fromIntegral wakeup) p 1; return ()
+ s <- peek p
+ if (s == 0xff)
+ then return ()
+ else c_startSignalHandler (fromIntegral s)
+
+ takeMVar prodding
putMVar prodding False
reqs' <- completeRequests reqs readfds writefds []
b <- takeMVar prodding
if (not b)
then do fd <- readIORef stick
- with 42 $ \pbuf -> do c_write (fromIntegral fd) pbuf 1; return ()
+ with 0xff $ \pbuf -> do c_write (fromIntegral fd) pbuf 1; return ()
else return ()
putMVar prodding True
+foreign import ccall unsafe "startSignalHandler"
+ c_startSignalHandler :: CInt -> IO ()
+
+foreign import ccall "setIOManagerPipe"
+ c_setIOManagerPipe :: CInt -> IO ()
+
-- -----------------------------------------------------------------------------
-- IO requests