[project @ 2000-12-31 16:58:05 by panne]

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

diff --git a/ghc/rts/Signals.c b/ghc/rts/Signals.c
index 7062102..3312b15 100644 (file)
--- a/ghc/rts/Signals.c
+++ b/ghc/rts/Signals.c
@@ -1,19 +1,27 @@
 /* -----------------------------------------------------------------------------
 /* -----------------------------------------------------------------------------

- * $Id: Signals.c,v 1.3 1999/01/26 11:12:49 simonm Exp $
+ * $Id: Signals.c,v 1.18 2000/08/25 13:12:07 simonmar Exp $
+ *
+ * (c) The GHC Team, 1998-1999

  *
  * Signal processing / handling.
  *
  * ---------------------------------------------------------------------------*/
 
  *
  * Signal processing / handling.
  *
  * ---------------------------------------------------------------------------*/
 

+#define NON_POSIX_SOURCE
+

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

+#ifndef mingw32_TARGET_OS
+

 #ifndef PAR
 
 #ifndef PAR
 

+/* SUP: The type of handlers is a little bit, well, doubtful... */

 static StgInt *handlers = NULL; /* Dynamically grown array of signal handlers */
 static StgInt nHandlers = 0;    /* Size of handlers array */
 
 static StgInt *handlers = NULL; /* Dynamically grown array of signal handlers */
 static StgInt nHandlers = 0;    /* Size of handlers array */
 

@@ -34,21 +42,20 @@ 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;
 }

@@ -69,7 +76,7 @@ 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

@@ -93,7 +100,7 @@ generic_handler(int sig)
        circumstances, depending on the signal.  
     */
 
        circumstances, depending on the signal.  
     */
 

-    *next_pending_handler++ = deRefStablePtr(handlers[sig]);
+    *next_pending_handler++ = deRefStablePtr(stgCast(StgStablePtr,handlers[sig]));

 
     /* stack full? */
     if (next_pending_handler == &pending_handler_buf[N_PENDING_HANDLERS]) {
 
     /* stack full? */
     if (next_pending_handler == &pending_handler_buf[N_PENDING_HANDLERS]) {

@@ -104,6 +111,8 @@ 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;

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

@@ -165,11 +174,13 @@ 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");
     }

@@ -188,7 +199,7 @@ sig_install(StgInt sig, StgInt spi, StgStablePtr handler, sigset_t *mask)
        * by freeing the previous handler if there was one.
        */       
       if (previous_spi >= 0) {
        * by freeing the previous handler if there was one.
        */       
       if (previous_spi >= 0) {

-         freeStablePtr(handlers[sig]);
+         freeStablePtr(stgCast(StgStablePtr,handlers[sig]));

       }
       return STG_SIG_ERR;
     }
       }
       return STG_SIG_ERR;
     }

@@ -209,12 +220,9 @@ 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);
+    scheduleThread(
+       createIOThread(RtsFlags.GcFlags.initialStkSize, 
+                     (StgClosure *) *next_pending_handler));

   }
 
   unblockUserSignals();
   }
 
   unblockUserSignals();

@@ -224,10 +232,8 @@ 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

@@ -235,3 +241,68 @@ 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
+
+  /* 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);
+  } else {
+      interruptStgRts();
+  }
+}
+
+/*
+ * 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_default_handlers()
+{
+    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. */
+      prog_belch("failed to install SIGINT handler");
+    }
+
+    siginterrupt(SIGINT, 1);
+}
+
+#endif /*! mingw32_TARGET_OS */