-% -----------------------------------------------------------------------------
-% $Id: Conc.lhs,v 1.4 2002/04/10 11:43:49 stolz Exp $
-%
-% (c) The University of Glasgow, 1994-2000
-%
-
-\section[GHC.Conc]{Module @GHC.Conc@}
-
-Basic concurrency stuff
-
-\begin{code}
-{-# OPTIONS -fno-implicit-prelude #-}
-
-module GHC.Conc
- ( ThreadId(..)
-
- -- Forking and suchlike
- , myThreadId -- :: IO ThreadId
- , killThread -- :: ThreadId -> IO ()
- , throwTo -- :: ThreadId -> Exception -> IO ()
- , par -- :: a -> b -> b
- , pseq -- :: a -> b -> b
- , yield -- :: IO ()
- , labelThread -- :: String -> IO ()
- , forkProcess -- :: IO Int
-
- -- Waiting
- , threadDelay -- :: Int -> IO ()
- , threadWaitRead -- :: Int -> IO ()
- , threadWaitWrite -- :: Int -> IO ()
-
- -- MVars
- , MVar -- abstract
- , newMVar -- :: a -> IO (MVar a)
- , newEmptyMVar -- :: IO (MVar a)
- , takeMVar -- :: MVar a -> IO a
- , putMVar -- :: MVar a -> a -> IO ()
- , tryTakeMVar -- :: MVar a -> IO (Maybe a)
- , tryPutMVar -- :: MVar a -> a -> IO Bool
- , isEmptyMVar -- :: MVar a -> IO Bool
- , addMVarFinalizer -- :: MVar a -> IO () -> IO ()
-
- ) where
-
-import Data.Maybe
-
-import GHC.Base
-import GHC.Err ( parError, seqError )
-import GHC.IOBase ( IO(..), MVar(..) )
-import GHC.Base ( Int(..) )
-import GHC.Exception ( Exception(..), AsyncException(..) )
-import GHC.Pack ( packCString# )
-
-infixr 0 `par`, `pseq`
-\end{code}
-
-%************************************************************************
-%* *
-\subsection{@ThreadId@, @par@, and @fork@}
-%* *
-%************************************************************************
-
\begin{code}
-data ThreadId = ThreadId ThreadId#
--- ToDo: data ThreadId = ThreadId (Weak ThreadId#)
--- But since ThreadId# is unlifted, the Weak type must use open
--- type variables.
-
---forkIO has now been hoisted out into the Concurrent library.
-
-killThread :: ThreadId -> IO ()
-killThread (ThreadId id) = IO $ \ s ->
- case (killThread# id (AsyncException ThreadKilled) s) of s1 -> (# s1, () #)
-
-throwTo :: ThreadId -> Exception -> IO ()
-throwTo (ThreadId id) ex = IO $ \ s ->
- case (killThread# id ex s) of s1 -> (# s1, () #)
-
-myThreadId :: IO ThreadId
-myThreadId = IO $ \s ->
- case (myThreadId# s) of (# s1, id #) -> (# s1, ThreadId id #)
-
-yield :: IO ()
-yield = IO $ \s ->
- case (yield# s) of s1 -> (# s1, () #)
-
-labelThread :: String -> IO ()
-labelThread str = IO $ \ s ->
- let ps = packCString# str
- adr = byteArrayContents# ps in
- case (labelThread# adr s) of s1 -> (# s1, () #)
-
-forkProcess :: IO Int
-forkProcess = IO $ \s -> case (forkProcess# s) of (# s1, id #) -> (# s1, (I# id) #)
-
--- Nota Bene: 'pseq' used to be 'seq'
--- but 'seq' is now defined in PrelGHC
---
--- "pseq" is defined a bit weirdly (see below)
+{-# LANGUAGE CPP, NoImplicitPrelude #-}
+{-# OPTIONS_GHC -fno-warn-missing-signatures #-}
+{-# OPTIONS_HADDOCK not-home #-}
+
+-----------------------------------------------------------------------------
+-- |
+-- Module : GHC.Conc
+-- Copyright : (c) The University of Glasgow, 1994-2002
+-- License : see libraries/base/LICENSE
+--
+-- Maintainer : cvs-ghc@haskell.org
+-- Stability : internal
+-- Portability : non-portable (GHC extensions)
--
--- The reason for the strange "0# -> parError" case is that
--- it fools the compiler into thinking that seq is non-strict in
--- its second argument (even if it inlines seq at the call site).
--- If it thinks seq is strict in "y", then it often evaluates
--- "y" before "x", which is totally wrong.
---
--- Just before converting from Core to STG there's a bit of magic
--- that recognises the seq# and eliminates the duff case.
-
-{-# INLINE pseq #-}
-pseq :: a -> b -> b
-pseq x y = case (seq# x) of { 0# -> seqError; _ -> y }
+-- Basic concurrency stuff.
+--
+-----------------------------------------------------------------------------
-{-# INLINE par #-}
-par :: a -> b -> b
-par x y = case (par# x) of { 0# -> parError; _ -> y }
-\end{code}
-
-%************************************************************************
-%* *
-\subsection[mvars]{M-Structures}
-%* *
-%************************************************************************
+-- 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:
-M-Vars are rendezvous points for concurrent threads. They begin
-empty, and any attempt to read an empty M-Var blocks. When an M-Var
-is written, a single blocked thread may be freed. Reading an M-Var
-toggles its state from full back to empty. Therefore, any value
-written to an M-Var may only be read once. Multiple reads and writes
-are allowed, but there must be at least one read between any two
-writes.
+#include "Typeable.h"
-\begin{code}
---Defined in IOBase to avoid cycle: data MVar a = MVar (SynchVar# RealWorld a)
-
-newEmptyMVar :: IO (MVar a)
-newEmptyMVar = IO $ \ s# ->
- case newMVar# s# of
- (# s2#, svar# #) -> (# s2#, MVar svar# #)
-
-takeMVar :: MVar a -> IO a
-takeMVar (MVar mvar#) = IO $ \ s# -> takeMVar# mvar# s#
-
-putMVar :: MVar a -> a -> IO ()
-putMVar (MVar mvar#) x = IO $ \ s# ->
- case putMVar# mvar# x s# of
- s2# -> (# s2#, () #)
-
-tryPutMVar :: MVar a -> a -> IO Bool
-tryPutMVar (MVar mvar#) x = IO $ \ s# ->
- case tryPutMVar# mvar# x s# of
- (# s, 0# #) -> (# s, False #)
- (# s, _ #) -> (# s, True #)
-
-newMVar :: a -> IO (MVar a)
-newMVar value =
- newEmptyMVar >>= \ mvar ->
- putMVar mvar value >>
- return mvar
-
--- tryTakeMVar is a non-blocking takeMVar
-tryTakeMVar :: MVar a -> IO (Maybe a)
-tryTakeMVar (MVar m) = IO $ \ s ->
- case tryTakeMVar# m s of
- (# s, 0#, _ #) -> (# s, Nothing #) -- MVar is empty
- (# s, _, a #) -> (# s, Just a #) -- MVar is full
-
-{-
- Low-level op. for checking whether an MVar is filled-in or not.
- Notice that the boolean value returned is just a snapshot of
- the state of the MVar. By the time you get to react on its result,
- the MVar may have been filled (or emptied) - so be extremely
- careful when using this operation.
-
- Use tryTakeMVar instead if possible.
-
- If you can re-work your abstractions to avoid having to
- depend on isEmptyMVar, then you're encouraged to do so,
- i.e., consider yourself warned about the imprecision in
- general of isEmptyMVar :-)
--}
-isEmptyMVar :: MVar a -> IO Bool
-isEmptyMVar (MVar mv#) = IO $ \ s# ->
- case isEmptyMVar# mv# s# of
- (# s2#, flg #) -> (# s2#, not (flg ==# 0#) #)
-
--- Like addForeignPtrFinalizer, but for MVars
-addMVarFinalizer :: MVar a -> IO () -> IO ()
-addMVarFinalizer (MVar m) finalizer =
- IO $ \s -> case mkWeak# m () finalizer s of { (# s1, w #) -> (# s1, () #) }
-\end{code}
-
-
-%************************************************************************
-%* *
-\subsection{Thread waiting}
-%* *
-%************************************************************************
-
-@threadDelay@ delays rescheduling of a thread until the indicated
-number of microseconds have elapsed. Generally, the microseconds are
-counted by the context switch timer, which ticks in virtual time;
-however, when there are no runnable threads, we don't accumulate any
-virtual time, so we start ticking in real time. (The granularity is
-the effective resolution of the context switch timer, so it is
-affected by the RTS -C option.)
-
-@threadWaitRead@ delays rescheduling of a thread until input on the
-specified file descriptor is available for reading (just like select).
-@threadWaitWrite@ is similar, but for writing on a file descriptor.
-
-\begin{code}
-threadDelay, threadWaitRead, threadWaitWrite :: Int -> IO ()
+-- #not-home
+module GHC.Conc
+ ( ThreadId(..)
+
+ -- * Forking and suchlike
+ , forkIO -- :: IO a -> IO ThreadId
+ , forkIOUnmasked
+ , forkOnIO -- :: Int -> IO a -> IO ThreadId
+ , forkOnIOUnmasked
+ , numCapabilities -- :: Int
+ , getNumCapabilities -- :: IO Int
+ , numSparks -- :: IO Int
+ , childHandler -- :: Exception -> IO ()
+ , myThreadId -- :: IO ThreadId
+ , killThread -- :: ThreadId -> IO ()
+ , throwTo -- :: ThreadId -> Exception -> IO ()
+ , par -- :: a -> b -> b
+ , pseq -- :: a -> b -> b
+ , runSparks
+ , yield -- :: IO ()
+ , labelThread -- :: ThreadId -> String -> IO ()
+
+ , ThreadStatus(..), BlockReason(..)
+ , threadStatus -- :: ThreadId -> IO ThreadStatus
+
+ -- * Waiting
+ , threadDelay -- :: Int -> IO ()
+ , registerDelay -- :: Int -> IO (TVar Bool)
+ , threadWaitRead -- :: Int -> IO ()
+ , threadWaitWrite -- :: Int -> IO ()
+ , closeFdWith -- :: (Fd -> IO ()) -> Fd -> IO ()
+
+ -- * TVars
+ , STM(..)
+ , atomically -- :: STM a -> IO a
+ , retry -- :: STM a
+ , orElse -- :: STM a -> STM a -> STM a
+ , throwSTM -- :: Exception e => e -> STM a
+ , catchSTM -- :: Exception e => STM a -> (e -> STM a) -> STM a
+ , alwaysSucceeds -- :: STM a -> STM ()
+ , always -- :: STM Bool -> STM ()
+ , TVar(..)
+ , newTVar -- :: a -> STM (TVar a)
+ , newTVarIO -- :: a -> STM (TVar a)
+ , readTVar -- :: TVar a -> STM a
+ , readTVarIO -- :: TVar a -> IO a
+ , writeTVar -- :: a -> TVar a -> STM ()
+ , unsafeIOToSTM -- :: IO a -> STM a
+
+ -- * Miscellaneous
+ , withMVar
+#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
+
+ , 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
+ , Signal, HandlerFun, setHandler, runHandlers
+#endif
+
+ , ensureIOManagerIsRunning
+
+#ifdef mingw32_HOST_OS
+ , ConsoleEvent(..)
+ , win32ConsoleHandler
+ , toWin32ConsoleEvent
+#endif
+ , setUncaughtExceptionHandler -- :: (Exception -> IO ()) -> IO ()
+ , getUncaughtExceptionHandler -- :: IO (Exception -> IO ())
+
+ , reportError, reportStackOverflow
+ ) where
+
+import GHC.Conc.IO
+import GHC.Conc.Sync
+
+#ifndef mingw32_HOST_OS
+import GHC.Conc.Signal
+#endif
-threadDelay (I# ms) = IO $ \s -> case delay# ms s of s -> (# s, () #)
-threadWaitRead (I# fd) = IO $ \s -> case waitRead# fd s of s -> (# s, () #)
-threadWaitWrite (I# fd) = IO $ \s -> case waitWrite# fd s of s -> (# s, () #)
\end{code}