1999-07-19 Roland McGrath <roland@baalperazim.frob.com>

	* hurd/hurdsig.c (_hurd_internal_post_signal): If a
	hurd_signal_preemptor matches but its `preemptor' field is null, use
	its `handler' field directly.  This is to comply with behavior
	documented in <hurd/sigpreempt.h>.

diff --git a/hurd/hurdsig.c b/hurd/hurdsig.c
index 1c1a22932c092d03786d927d238d4ba182e0ad0a..f2a01201b56645cd2cc15ae6c3efbbf7a1003eae 100644 (file)
--- a/hurd/hurdsig.c
+++ b/hurd/hurdsig.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 1991, 92, 93, 94, 95, 96, 97, 98 Free Software Foundation, Inc.
+/* Copyright (C) 1991,92,93,94,95,96,97,98,99 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
 
    The GNU C Library is free software; you can redistribute it and/or
@@ -448,7 +448,6 @@ _hurd_internal_post_signal (struct hurd_sigstate *ss,
   error_t err;
   struct machine_thread_all_state thread_state;
   enum { stop, ignore, core, term, handle } act;
-  struct hurd_signal_preemptor *pe;
   sighandler_t handler;
   sigset_t pending;
   int ss_suspended;
@@ -549,20 +548,38 @@ _hurd_internal_post_signal (struct hurd_sigstate *ss,
 
   /* Check for a preempted signal.  Preempted signals can arrive during
      critical sections.  */
+  {
+    inline sighandler_t try_preemptor (struct hurd_signal_preemptor *pe)
+      {                                /* PE cannot be null.  */
+       do
+         {
+           if (HURD_PREEMPT_SIGNAL_P (pe, signo, detail->code))
+             {
+               if (pe->preemptor)
+                 {
+                   sighandler_t handler = (*pe->preemptor) (pe, ss,
+                                                            &signo, detail);
+                   if (handler != SIG_ERR)
+                     return handler;
+                 }
+               else
+                 return pe->handler;
+             }
+           pe = pe->next;
+         } while (pe != 0);
+       return SIG_ERR;
+      }
 
-  handler = SIG_ERR;
-  for (pe = ss->preemptors; pe && handler == SIG_ERR; pe = pe->next)
-    if (HURD_PREEMPT_SIGNAL_P (pe, signo, detail->code))
-      handler = (*pe->preemptor) (pe, ss, &signo, detail);
+    handler = ss->preemptors ? try_preemptor (ss->preemptors) : SIG_ERR;
 
-  if (handler == SIG_ERR && (__sigmask (signo) & _hurdsig_preempted_set))
-    {
-      __mutex_lock (&_hurd_siglock);
-      for (pe = _hurdsig_preemptors; pe && handler == SIG_ERR; pe = pe->next)
-       if (HURD_PREEMPT_SIGNAL_P (pe, signo, detail->code))
-         handler = (*pe->preemptor) (pe, ss, &signo, detail);
-      __mutex_unlock (&_hurd_siglock);
-    }
+    /* If no thread-specific preemptor, check for a global one.  */
+    if (handler == SIG_ERR && (__sigmask (signo) & _hurdsig_preempted_set))
+      {
+       __mutex_lock (&_hurd_siglock);
+       handler = try_preemptor (_hurdsig_preemptors);
+       __mutex_unlock (&_hurd_siglock);
+      }
+  }
 
   ss_suspended = 0;