[project @ 2000-02-14 10:58:05 by sewardj]

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

diff --git a/ghc/rts/Signals.c b/ghc/rts/Signals.c
index 219ce67..9c6e058 100644 (file)
--- a/ghc/rts/Signals.c
+++ b/ghc/rts/Signals.c
@@ -1,5 +1,5 @@
 /* -----------------------------------------------------------------------------
 /* -----------------------------------------------------------------------------

- * $Id: Signals.c,v 1.5 1999/03/02 20:01:55 sof Exp $
+ * $Id: Signals.c,v 1.12 2000/01/13 12:40:16 simonmar Exp $

  *
  * (c) The GHC Team, 1998-1999
  *
  *
  * (c) The GHC Team, 1998-1999
  *

@@ -9,6 +9,7 @@
 
 #include "Rts.h"
 #include "SchedAPI.h"
 
 #include "Rts.h"
 #include "SchedAPI.h"

+#include "Schedule.h"

 #include "Signals.h"
 #include "RtsUtils.h"
 #include "RtsFlags.h"
 #include "Signals.h"
 #include "RtsUtils.h"
 #include "RtsFlags.h"

@@ -38,21 +39,20 @@ more_handlers(I_ sig)
     I_ i;
 
     if (sig < nHandlers)
     I_ i;
 
     if (sig < nHandlers)

-       return;
+      return;

 
     if (handlers == NULL)
 
     if (handlers == NULL)

-       handlers = (I_ *) malloc((sig + 1) * sizeof(I_));
+      handlers = (I_ *) malloc((sig + 1) * sizeof(I_));

     else
     else

-       handlers = (I_ *) realloc(handlers, (sig + 1) * sizeof(I_));
+      handlers = (I_ *) realloc(handlers, (sig + 1) * sizeof(I_));

 
     if (handlers == NULL) {
 
     if (handlers == NULL) {

-       fflush(stdout);
-       fprintf(stderr, "VM exhausted (in more_handlers)\n");
-       exit(EXIT_FAILURE);
+      /* don't fflush(stdout); WORKAROUND bug in Linux glibc */
+      barf("VM exhausted (in more_handlers)");

     }
     for(i = nHandlers; i <= sig; i++)
     }
     for(i = nHandlers; i <= sig; i++)

-       /* Fill in the new slots with default actions */
-       handlers[i] = STG_SIG_DFL;
+      /* Fill in the new slots with default actions */
+      handlers[i] = STG_SIG_DFL;

 
     nHandlers = sig + 1;
 }
 
     nHandlers = sig + 1;
 }

@@ -73,7 +73,7 @@ generic_handler(int sig)
        either.  However, we have to schedule a new thread somehow.
 
        It's probably ok to request a context switch and allow the
        either.  However, we have to schedule a new thread somehow.
 
        It's probably ok to request a context switch and allow the

-       scheduler to  start the handler thread, but how to we
+       scheduler to  start the handler thread, but how do we

        communicate this to the scheduler?
 
        We need some kind of locking, but with low overhead (i.e. no
        communicate this to the scheduler?
 
        We need some kind of locking, but with low overhead (i.e. no

@@ -108,6 +108,8 @@ generic_handler(int sig)
     sigemptyset(&signals);
     sigaddset(&signals, sig);
     sigprocmask(SIG_UNBLOCK, &signals, NULL);
     sigemptyset(&signals);
     sigaddset(&signals, sig);
     sigprocmask(SIG_UNBLOCK, &signals, NULL);

+
+    context_switch = 1;

 }
 
 /* -----------------------------------------------------------------------------
 }
 
 /* -----------------------------------------------------------------------------

@@ -169,11 +171,13 @@ sig_install(StgInt sig, StgInt spi, StgStablePtr handler, sigset_t *mask)
        sigdelset(&userSignals, sig);
         action.sa_handler = SIG_DFL;
        break;
        sigdelset(&userSignals, sig);
         action.sa_handler = SIG_DFL;
        break;

+

     case STG_SIG_HAN:
        handlers[sig] = (I_)handler;
        sigaddset(&userSignals, sig);
        action.sa_handler = generic_handler;
        break;
     case STG_SIG_HAN:
        handlers[sig] = (I_)handler;
        sigaddset(&userSignals, sig);
        action.sa_handler = generic_handler;
        break;

+

     default:
         barf("sig_install: bad spi");
     }
     default:
         barf("sig_install: bad spi");
     }

@@ -213,10 +217,6 @@ start_signal_handlers(void)
 
     next_pending_handler--;
 
 
     next_pending_handler--;
 

-    /* create*Thread  puts the thread on the head of the runnable
-     * queue, hence it will be run next.  Poor man's priority
-     * scheduling.
-     */

     createIOThread(RtsFlags.GcFlags.initialStkSize, 
                   (StgClosure *) *next_pending_handler);
   }
     createIOThread(RtsFlags.GcFlags.initialStkSize, 
                   (StgClosure *) *next_pending_handler);
   }

@@ -228,10 +228,8 @@ start_signal_handlers(void)
 StgInt 
 sig_install(StgInt sig, StgInt spi, StgStablePtr handler, sigset_t *mask)
 {
 StgInt 
 sig_install(StgInt sig, StgInt spi, StgStablePtr handler, sigset_t *mask)
 {

-    fflush(stdout);
-    fprintf(stderr,
-           "No signal handling support in a parallel implementation.\n");
-    exit(EXIT_FAILURE);
+  /* don't fflush(stdout); WORKAROUND bug in Linux glibc */
+  barf("no signal handling support in a parallel implementation");

 }
 
 void
 }
 
 void

@@ -240,4 +238,62 @@ start_signal_handlers(void)
 }
 #endif
 
 }
 #endif
 

+/* -----------------------------------------------------------------------------
+   SIGINT handler.
+
+   We like to shutdown nicely after receiving a SIGINT, write out the
+   stats, write profiling info, close open files and flush buffers etc.
+   -------------------------------------------------------------------------- */
+
+#ifdef SMP
+pthread_t startup_guy;
+#endif
+
+static void
+shutdown_handler(int sig STG_UNUSED)
+{
+#ifdef SMP
+  /* if I'm a worker thread, send this signal to the guy who
+   * originally called startupHaskell().  Since we're handling
+   * the signal, it won't be a "send to all threads" type of signal
+   * (according to the POSIX threads spec).
+   */
+  if (pthread_self() != startup_guy) {
+    pthread_kill(startup_guy, sig);
+  } else
+#endif
+
+  shutdownHaskellAndExit(EXIT_INTERRUPTED);
+}
+
+/*
+ * The RTS installs a default signal handler for catching
+ * SIGINT, so that we can perform an orderly shutdown.
+ *
+ * Haskell code may install their own SIGINT handler, which is
+ * fine, provided they're so kind as to put back the old one
+ * when they de-install.
+ */
+void
+init_shutdown_handler()
+{
+    struct sigaction action,oact;
+
+#ifdef SMP
+    startup_guy = pthread_self();
+#endif
+    action.sa_handler = shutdown_handler;
+    sigemptyset(&action.sa_mask);
+    action.sa_flags = 0;
+    if (sigaction(SIGINT, &action, &oact) != 0) {
+      /* Oh well, at least we tried. */
+#ifdef DEBUG
+      fprintf(stderr, "init_shutdown_handler: failed to reg SIGINT handler");
+#endif
+    }
+}
+
+
+
+

 #endif /*! mingw32_TARGET_OS */
 #endif /*! mingw32_TARGET_OS */