/* -----------------------------------------------------------------------------
- * $Id: Signals.c,v 1.30 2002/12/05 14:20:55 stolz Exp $
*
* (c) The GHC Team, 1998-1999
*
#include "Signals.h"
#include "RtsUtils.h"
#include "RtsFlags.h"
-#include "StablePriv.h"
#ifdef alpha_TARGET_ARCH
-# include <machine/fpu.h>
+# if defined(linux_TARGET_OS)
+# include <asm/fpu.h>
+# else
+# include <machine/fpu.h>
+# endif
#endif
#ifdef HAVE_UNISTD_H
#include <stdlib.h>
-#ifndef mingw32_TARGET_OS
+/* This curious flag is provided for the benefit of the Haskell binding
+ * to POSIX.1 to control whether or not to include SA_NOCLDSTOP when
+ * installing a SIGCHLD handler.
+ *
+ */
+StgInt nocldstop = 0;
-#ifndef PAR
+#if defined(RTS_USER_SIGNALS)
/* SUP: The type of handlers is a little bit, well, doubtful... */
static StgInt *handlers = NULL; /* Dynamically grown array of signal handlers */
StgPtr pending_handler_buf[N_PENDING_HANDLERS];
StgPtr *next_pending_handler = pending_handler_buf;
-StgInt nocldstop = 0;
+/* -----------------------------------------------------------------------------
+ * Signal handling
+ * -------------------------------------------------------------------------- */
+
+#ifdef RTS_SUPPORTS_THREADS
+pthread_t signalHandlingThread;
+#endif
+
+// Handle all signals in the current thread.
+// Called from Capability.c whenever the main capability is granted to a thread
+// and in installDefaultHandlers
+void
+handleSignalsInThisThread(void)
+{
+#ifdef RTS_SUPPORTS_THREADS
+ signalHandlingThread = pthread_self();
+#endif
+}
/* -----------------------------------------------------------------------------
* Allocate/resize the table of signal handlers.
return;
if (handlers == NULL)
- handlers = (StgInt *) malloc((sig + 1) * sizeof(StgInt));
+ handlers = (StgInt *)stgMallocBytes((sig + 1) * sizeof(StgInt), "more_handlers");
else
- handlers = (StgInt *) realloc(handlers, (sig + 1) * sizeof(StgInt));
+ handlers = (StgInt *)stgReallocBytes(handlers, (sig + 1) * sizeof(StgInt), "more_handlers");
- if (handlers == NULL) {
- // don't fflush(stdout); WORKAROUND bug in Linux glibc
- barf("VM exhausted (in more_handlers)");
- }
for(i = nHandlers; i <= sig; i++)
// Fill in the new slots with default actions
handlers[i] = STG_SIG_DFL;
{
sigset_t signals;
+#if defined(THREADED_RTS)
+ // Make the thread that currently holds the main capability
+ // handle the signal.
+ // This makes sure that awaitEvent() is interrupted
+ // and it (hopefully) prevents race conditions
+ // (signal handlers are not atomic with respect to other threads)
+
+ if(pthread_self() != signalHandlingThread) {
+ pthread_kill(signalHandlingThread, sig);
+ return;
+ }
+#endif
+
/* Can't call allocate from here. Probably can't call malloc
either. However, we have to schedule a new thread somehow.
// stack full?
if (next_pending_handler == &pending_handler_buf[N_PENDING_HANDLERS]) {
- barf("too many pending signals");
+ errorBelch("too many pending signals");
+ stg_exit(EXIT_FAILURE);
}
// re-establish the signal handler, and carry on
void
blockUserSignals(void)
{
- sigprocmask(SIG_SETMASK, &userSignals, &savedSignals);
+ sigprocmask(SIG_BLOCK, &userSignals, &savedSignals);
}
void
previous_spi = handlers[sig];
+ action.sa_flags = 0;
+
switch(spi) {
case STG_SIG_IGN:
handlers[sig] = STG_SIG_IGN;
}
return STG_SIG_ERR;
}
-
+
if (previous_spi == STG_SIG_DFL || previous_spi == STG_SIG_IGN
|| previous_spi == STG_SIG_ERR) {
return previous_spi;
}
}
-#else // PAR
+#else /* !RTS_USER_SIGNALS */
StgInt
-stg_sig_install(StgInt sig, StgInt spi, StgStablePtr handler, sigset_t *mask)
+stg_sig_install(StgInt sig STG_UNUSED,
+ StgInt spi STG_UNUSED,
+ StgStablePtr* handler STG_UNUSED,
+ void* mask STG_UNUSED)
{
- // don't fflush(stdout); WORKAROUND bug in Linux glibc
- barf("no signal handling support in a parallel implementation");
+ //barf("User signals not supported");
+ return STG_SIG_DFL;
}
-void
-startSignalHandlers(void)
-{
-}
#endif
+#if defined(RTS_USER_SIGNALS)
/* -----------------------------------------------------------------------------
* SIGINT handler.
*
pthread_kill(startup_guy, sig);
return;
}
+ // ToDo: The code for the threaded RTS below does something very
+ // similar. Maybe the SMP special case is not needed
+ // -- Wolfgang Thaller
+#elif defined(THREADED_RTS)
+ // Make the thread that currently holds the main capability
+ // handle the signal.
+ // This makes sure that awaitEvent() is interrupted
+ if(pthread_self() != signalHandlingThread) {
+ pthread_kill(signalHandlingThread, sig);
+ return;
+ }
#endif
// If we're already trying to interrupt the RTS, terminate with
// extreme prejudice. So the first ^C tries to exit the program
// cleanly, and the second one just kills it.
if (interrupted) {
- exit(EXIT_INTERRUPTED);
+ stg_exit(EXIT_INTERRUPTED);
} else {
interruptStgRts();
}
#ifdef SMP
startup_guy = pthread_self();
#endif
+#ifdef RTS_SUPPORTS_THREADS
+ handleSignalsInThisThread();
+#endif
// install the SIGINT handler
action.sa_handler = shutdown_handler;
sigemptyset(&action.sa_mask);
action.sa_flags = 0;
if (sigaction(SIGINT, &action, &oact) != 0) {
- prog_belch("warning: failed to install SIGINT handler");
+ errorBelch("warning: failed to install SIGINT handler");
}
-#ifndef cygwin32_TARGET_OS
+#if defined(HAVE_SIGINTERRUPT)
siginterrupt(SIGINT, 1); // isn't this the default? --SDM
#endif
sigemptyset(&action.sa_mask);
action.sa_flags = 0;
if (sigaction(SIGCONT, &action, &oact) != 0) {
- prog_belch("warning: failed to install SIGCONT handler");
+ errorBelch("warning: failed to install SIGCONT handler");
}
// install the SIGFPE handler
sigemptyset(&action.sa_mask);
action.sa_flags = 0;
if (sigaction(SIGFPE, &action, &oact) != 0) {
- prog_belch("warning: failed to install SIGFPE handler");
+ errorBelch("warning: failed to install SIGFPE handler");
}
#endif
#endif
}
-#endif /*! mingw32_TARGET_OS */
+#endif /* RTS_USER_SIGNALS */