diff options
Diffstat (limited to 'macosx/tclMacOSXNotify.c')
| -rw-r--r-- | macosx/tclMacOSXNotify.c | 162 |
1 files changed, 155 insertions, 7 deletions
diff --git a/macosx/tclMacOSXNotify.c b/macosx/tclMacOSXNotify.c index be13164..15a1cd5 100644 --- a/macosx/tclMacOSXNotify.c +++ b/macosx/tclMacOSXNotify.c @@ -458,6 +458,20 @@ static int receivePipe = -1; /* Output end of triggerPipe */ static int notifierThreadRunning; /* + * The following static flag indicates that async handlers are pending. + */ + +#if TCL_THREADS +static int asyncPending = 0; +#endif + +/* + * Signal mask information for notifier thread. + */ +static sigset_t notifierSigMask; +static sigset_t allSigMask; + +/* * This is the thread ID of the notifier thread that does select. Only valid * when notifierThreadRunning is non-zero. * @@ -803,6 +817,15 @@ StartNotifierThread(void) int result; pthread_attr_t attr; + /* + * Arrange for the notifier thread to start with all + * signals blocked. In its mainloop it unblocks the + * signals at safe points. + */ + + sigfillset(&allSigMask); + pthread_sigmask(SIG_BLOCK, &allSigMask, ¬ifierSigMask); + pthread_attr_init(&attr); pthread_attr_setscope(&attr, PTHREAD_SCOPE_SYSTEM); pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_JOINABLE); @@ -814,6 +837,12 @@ StartNotifierThread(void) Tcl_Panic("StartNotifierThread: unable to start notifier thread"); } notifierThreadRunning = 1; + + /* + * Restore original signal mask. + */ + + pthread_sigmask(SIG_SETMASK, ¬ifierSigMask, NULL); } UNLOCK_NOTIFIER_INIT; } @@ -876,6 +905,14 @@ TclpFinalizeNotifier( "thread"); } notifierThreadRunning = 0; + + /* + * If async marks are outstanding, perform actions now. + */ + if (asyncPending) { + asyncPending = 0; + TclAsyncMarkFromNotifier(); + } } close(receivePipe); @@ -1283,6 +1320,29 @@ FileHandlerEventProc( /* *---------------------------------------------------------------------- * + * TclpNotifierData -- + * + * This function returns a ClientData pointer to be associated + * with a Tcl_AsyncHandler. + * + * Results: + * On MacOSX, returns always NULL. + * + * Side effects: + * None. + * + *---------------------------------------------------------------------- + */ + +ClientData +TclpNotifierData(void) +{ + return NULL; +} + +/* + *---------------------------------------------------------------------- + * * TclpWaitForEvent -- * * This function is called by Tcl_DoOneEvent to wait for new events on @@ -1829,6 +1889,61 @@ TclUnixWaitForFile( /* *---------------------------------------------------------------------- * + * TclAsyncNotifier -- + * + * This procedure sets the async mark of an async handler to a + * given value, if it is called from the notifier thread. + * + * Result: + * True, when the handler will be marked, false otherwise. + * + * Side effetcs: + * The trigger pipe is written when called from the notifier + * thread. + * + *---------------------------------------------------------------------- + */ + +int +TclAsyncNotifier( + int sigNumber, /* Signal number. */ + TCL_UNUSED(Tcl_ThreadId), /* Target thread. */ + TCL_UNUSED(ClientData), /* Notifier data. */ + int *flagPtr, /* Flag to mark. */ + int value) /* Value of mark. */ +{ +#if TCL_THREADS + /* + * WARNING: + * This code most likely runs in a signal handler. Thus, + * only few async-signal-safe system calls are allowed, + * e.g. pthread_self(), sem_post(), write(). + */ + + if (pthread_equal(pthread_self(), (pthread_t) notifierThread)) { + if (notifierThreadRunning) { + *flagPtr = value; + if (!asyncPending) { + asyncPending = 1; + write(triggerPipe, "S", 1); + } + return 1; + } + return 0; + } + + /* + * Re-send the signal to the notifier thread. + */ + + pthread_kill((pthread_t) notifierThread, sigNumber); +#endif + return 0; +} + +/* + *---------------------------------------------------------------------- + * * NotifierThreadProc -- * * This routine is the initial (and only) function executed by the @@ -1856,7 +1971,7 @@ NotifierThreadProc( { ThreadSpecificData *tsdPtr; fd_set readableMask, writableMask, exceptionalMask; - int i, numFdBits = 0, polling; + int i, ret, numFdBits = 0, polling; struct timeval poll = {0., 0.}, *timePtr; char buf[2]; @@ -1909,8 +2024,25 @@ NotifierThreadProc( } FD_SET(receivePipe, &readableMask); - if (select(numFdBits, &readableMask, &writableMask, &exceptionalMask, - timePtr) == -1) { + /* + * Signals are unblocked only during select(). + */ + + pthread_sigmask(SIG_SETMASK, ¬ifierSigMask, NULL); + ret = select(numFdBits, &readableMask, &writableMask, &exceptionalMask, + timePtr); + pthread_sigmask(SIG_BLOCK, &allSigMask, NULL); + + if (ret == -1) { + /* + * In case a signal was caught during select(), + * perform work on async handlers now. + */ + if (errno == EINTR && asyncPending) { + asyncPending = 0; + TclAsyncMarkFromNotifier(); + } + /* * Try again immediately on an error. */ @@ -1998,6 +2130,11 @@ NotifierThreadProc( break; } + + if (asyncPending) { + asyncPending = 0; + TclAsyncMarkFromNotifier(); + } } } pthread_exit(0); @@ -2084,12 +2221,17 @@ AtForkChild(void) */ #if defined(USE_OS_UNFAIR_LOCK) - tsdPtr->tsdLock = OS_UNFAIR_LOCK_INIT; + notifierInitLock = OS_UNFAIR_LOCK_INIT; + notifierLock = OS_UNFAIR_LOCK_INIT; + tsdPtr->tsdLock = OS_UNFAIR_LOCK_INIT; #else - UNLOCK_NOTIFIER_TSD; - UNLOCK_NOTIFIER; - UNLOCK_NOTIFIER_INIT; + UNLOCK_NOTIFIER_TSD; + UNLOCK_NOTIFIER; + UNLOCK_NOTIFIER_INIT; #endif + + asyncPending = 0; + if (tsdPtr->runLoop) { tsdPtr->runLoop = NULL; if (!noCFafterFork) { @@ -2119,6 +2261,12 @@ AtForkChild(void) if (!noCFafterFork) { Tcl_InitNotifier(); } + + /* + * Restart the notifier thread for signal handling. + */ + + StartNotifierThread(); } } #endif /* HAVE_PTHREAD_ATFORK */ |