[project @ 2003-01-10 22:08:20 by wolfgang]

[ghc-hetmet.git] / ghc / rts / Signals.c

diff --git a/ghc/rts/Signals.c b/ghc/rts/Signals.c
index b94ad6d..8e33d9d 100644 (file)
--- a/ghc/rts/Signals.c
+++ b/ghc/rts/Signals.c
@@ -1,5 +1,5 @@
 /* -----------------------------------------------------------------------------
- * $Id: Signals.c,v 1.25 2002/07/02 12:24:48 simonmar Exp $
+ * $Id: Signals.c,v 1.32 2003/01/10 22:08:20 wolfgang Exp $
  *
  * (c) The GHC Team, 1998-1999
  *
@@ -19,9 +19,19 @@
 #include "StablePriv.h"
 
 #ifdef alpha_TARGET_ARCH
-#include <machine/fpu.h>
+# include <machine/fpu.h>
 #endif
 
+#ifdef HAVE_UNISTD_H
+# include <unistd.h>
+#endif
+
+#ifdef HAVE_SIGNAL_H
+# include <signal.h>
+#endif
+
+#include <stdlib.h>
+
 #ifndef mingw32_TARGET_OS
 
 #ifndef PAR
@@ -127,7 +137,8 @@ generic_handler(int sig)
 
     // stack full?
     if (next_pending_handler == &pending_handler_buf[N_PENDING_HANDLERS]) {
-       barf("too many pending signals");
+       prog_belch("too many pending signals");
+       stg_exit(EXIT_FAILURE);
     }
     
     // re-establish the signal handler, and carry on
@@ -159,7 +170,7 @@ initUserSignals(void)
 void
 blockUserSignals(void)
 {
-    sigprocmask(SIG_SETMASK, &userSignals, &savedSignals);
+    sigprocmask(SIG_BLOCK, &userSignals, &savedSignals);
 }
 
 void
@@ -186,17 +197,17 @@ awaitUserSignals(void)
  * Install a Haskell signal handler.
  * -------------------------------------------------------------------------- */
 
-StgInt 
-stg_sig_install(StgInt sig, StgInt spi, StgStablePtr handler, sigset_t *mask)
+int
+stg_sig_install(int sig, int spi, StgStablePtr *handler, void *mask)
 {
-    sigset_t signals;
+    sigset_t signals, osignals;
     struct sigaction action;
     StgInt previous_spi;
 
     // Block the signal until we figure out what to do
     // Count on this to fail if the signal number is invalid
     if (sig < 0 || sigemptyset(&signals) ||
-       sigaddset(&signals, sig) || sigprocmask(SIG_BLOCK, &signals, NULL)) {
+       sigaddset(&signals, sig) || sigprocmask(SIG_BLOCK, &signals, &osignals)) {
        return STG_SIG_ERR;
     }
     
@@ -218,9 +229,13 @@ stg_sig_install(StgInt sig, StgInt spi, StgStablePtr handler, sigset_t *mask)
        break;
 
     case STG_SIG_HAN:
-       handlers[sig] = (StgInt)handler;
+    case STG_SIG_RST:
+       handlers[sig] = (StgInt)*handler;
        sigaddset(&userSignals, sig);
        action.sa_handler = generic_handler;
+       if (spi == STG_SIG_RST) {
+           action.sa_flags = SA_RESETHAND;
+       }
        n_haskell_handlers++;
        break;
 
@@ -228,15 +243,15 @@ stg_sig_install(StgInt sig, StgInt spi, StgStablePtr handler, sigset_t *mask)
         barf("stg_sig_install: bad spi");
     }
 
-    if (mask != 0)
-        action.sa_mask = *mask;
+    if (mask != NULL)
+        action.sa_mask = *(sigset_t *)mask;
     else
        sigemptyset(&action.sa_mask);
 
-    action.sa_flags = sig == SIGCHLD && nocldstop ? SA_NOCLDSTOP : 0;
+    action.sa_flags |= sig == SIGCHLD && nocldstop ? SA_NOCLDSTOP : 0;
 
     if (sigaction(sig, &action, NULL) || 
-       sigprocmask(SIG_UNBLOCK, &signals, NULL)) 
+       sigprocmask(SIG_SETMASK, &osignals, NULL)) 
     {
        // need to return an error code, so avoid a stable pointer leak
        // by freeing the previous handler if there was one.
@@ -247,7 +262,13 @@ stg_sig_install(StgInt sig, StgInt spi, StgStablePtr handler, sigset_t *mask)
        return STG_SIG_ERR;
     }
     
-    return previous_spi;
+    if (previous_spi == STG_SIG_DFL || previous_spi == STG_SIG_IGN
+       || previous_spi == STG_SIG_ERR) {
+       return previous_spi;
+    } else {
+       *handler = (StgStablePtr)previous_spi;
+       return STG_SIG_HAN;
+    }
 }
 
 /* -----------------------------------------------------------------------------
@@ -270,6 +291,27 @@ startSignalHandlers(void)
   unblockUserSignals();
 }
 
+/* ----------------------------------------------------------------------------
+ * Mark signal handlers during GC.
+ *
+ * We do this rather than trying to start all the signal handlers
+ * prior to GC, because that requires extra heap for the new threads.
+ * Signals must be blocked (see blockUserSignals() above) during GC to
+ * avoid race conditions.
+ * -------------------------------------------------------------------------- */
+
+void
+markSignalHandlers (evac_fn evac)
+{
+    StgPtr *p;
+
+    p = next_pending_handler;
+    while (p != pending_handler_buf) {
+       p--;
+       evac((StgClosure **)p);
+    }
+}
+
 #else // PAR
 StgInt 
 stg_sig_install(StgInt sig, StgInt spi, StgStablePtr handler, sigset_t *mask)