[project @ 2000-03-14 09:55:05 by simonmar]

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

diff --git a/ghc/rts/Signals.c b/ghc/rts/Signals.c
index 6e5d859..90b46ba 100644 (file)
--- a/ghc/rts/Signals.c
+++ b/ghc/rts/Signals.c
@@ -1,5 +1,5 @@
 /* -----------------------------------------------------------------------------
- * $Id: Signals.c,v 1.8 1999/09/22 11:53:33 sof Exp $
+ * $Id: Signals.c,v 1.14 2000/02/29 14:38:19 simonmar Exp $
  *
  * (c) The GHC Team, 1998-1999
  *
@@ -48,8 +48,7 @@ more_handlers(I_ sig)
 
     if (handlers == NULL) {
       /* don't fflush(stdout); WORKAROUND bug in Linux glibc */
-      fprintf(stderr, "VM exhausted (in more_handlers)\n");
-      exit(EXIT_FAILURE);
+      barf("VM exhausted (in more_handlers)");
     }
     for(i = nHandlers; i <= sig; i++)
       /* Fill in the new slots with default actions */
@@ -218,10 +217,6 @@ start_signal_handlers(void)
 
     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);
   }
@@ -234,9 +229,7 @@ StgInt
 sig_install(StgInt sig, StgInt spi, StgStablePtr handler, sigset_t *mask)
 {
   /* don't fflush(stdout); WORKAROUND bug in Linux glibc */
-  fprintf(stderr,
-         "No signal handling support in a parallel implementation.\n");
-  exit(EXIT_FAILURE);
+  barf("no signal handling support in a parallel implementation");
 }
 
 void
@@ -245,38 +238,66 @@ start_signal_handlers(void)
 }
 #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)
+shutdown_handler(int sig STG_UNUSED)
 {
-  shutdownHaskellAndExit(EXIT_FAILURE);
+#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
+
+    interruptStgRts();
 }
 
 /*
  * The RTS installs a default signal handler for catching
- * SIGINT, so that we can perform an orderly shutdown (finalising
- * objects and flushing buffers etc.)
+ * 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.
+ *
+ * We ignore SIGPIPE, because our I/O library handles EPIPE properly,
+ * and a SIGPIPE tends to cause the program to exit silently and
+ * mysteriously.
  */
 void
-init_shutdown_handler()
+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. */
-#ifdef DEBUG
-      fprintf(stderr, "init_shutdown_handler: failed to reg SIGINT handler");
-#endif
+      prog_belch("failed to install SIGINT handler");
     }
-}
-
-
 
+    action.sa_handler = SIG_IGN;
+    if (sigaction(SIGPIPE, &action, &oact) != 0) {
+      prog_belch("failed to install SIGINT handler");
+    }
+}
 
 #endif /*! mingw32_TARGET_OS */