[src/netbsd-2-0]: src/sys/kern Pullup rev 1.190 (requested by matt in ticket ...

[jmc <jmc%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/9a42b9bdb5c8
branches:  netbsd-2-0
changeset: 560219:9a42b9bdb5c8
user:      jmc <jmc%NetBSD.org@localhost>
date:      Thu Apr 01 23:28:33 2004 +0000

description:
Pullup rev 1.190 (requested by matt in ticket #43)

If a signal is the result of trap, only invoke a supplied handler
if it's not blocked.  Otherwise (it if it blocked or the handler
is set to SIG_IGN) reset the signal back to its default settings
so that a coredump can be generated.

diffstat:

 sys/kern/kern_sig.c |  69 ++++++++++++++++++++++++++++++++++++----------------
 1 files changed, 47 insertions(+), 22 deletions(-)

diffs (104 lines):

diff -r 201adee8585c -r 9a42b9bdb5c8 sys/kern/kern_sig.c
--- a/sys/kern/kern_sig.c       Thu Apr 01 23:08:12 2004 +0000
+++ b/sys/kern/kern_sig.c       Thu Apr 01 23:28:33 2004 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: kern_sig.c,v 1.189 2004/03/26 17:13:37 drochner Exp $  */
+/*     $NetBSD: kern_sig.c,v 1.189.2.1 2004/04/01 23:28:33 jmc Exp $   */
 
 /*
  * Copyright (c) 1982, 1986, 1989, 1991, 1993
@@ -37,7 +37,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: kern_sig.c,v 1.189 2004/03/26 17:13:37 drochner Exp $");
+__KERNEL_RCSID(0, "$NetBSD: kern_sig.c,v 1.189.2.1 2004/04/01 23:28:33 jmc Exp $");
 
 #include "opt_ktrace.h"
 #include "opt_compat_sunos.h"
@@ -87,7 +87,7 @@
 static ksiginfo_t *ksiginfo_get(struct proc *, int);
 static void    kpsignal2(struct proc *, const ksiginfo_t *, int);
 
-sigset_t       contsigmask, stopsigmask, sigcantmask;
+sigset_t       contsigmask, stopsigmask, sigcantmask, sigtrapmask;
 
 struct pool    sigacts_pool;   /* memory pool for sigacts structures */
 struct pool    siginfo_pool;   /* memory pool for siginfo structures */
@@ -206,6 +206,12 @@
            NULL);
        exithook_establish(ksiginfo_exithook, NULL);
        exechook_establish(ksiginfo_exithook, NULL);
+
+       sigaddset(&sigtrapmask, SIGSEGV);
+       sigaddset(&sigtrapmask, SIGBUS);
+       sigaddset(&sigtrapmask, SIGILL);
+       sigaddset(&sigtrapmask, SIGFPE);
+       sigaddset(&sigtrapmask, SIGTRAP);
 }
 
 /*
@@ -999,25 +1005,44 @@
        /*
         * If proc is traced, always give parent a chance.
         */
-       if (p->p_flag & P_TRACED)
-               action = SIG_DFL;
-       else {
-               /*
-                * If the signal is being ignored,
-                * then we forget about it immediately.
-                * (Note: we don't set SIGCONT in p_sigctx.ps_sigignore,
-                * and if it is set to SIG_IGN,
-                * action will be SIG_DFL here.)
-                */
-               if (sigismember(&p->p_sigctx.ps_sigignore, signum))
-                       return;
-               if (sigismember(&p->p_sigctx.ps_sigmask, signum))
-                       action = SIG_HOLD;
-               else if (sigismember(&p->p_sigctx.ps_sigcatch, signum))
-                       action = SIG_CATCH;
-               else {
-                       action = SIG_DFL;
-
+       action = SIG_DFL;
+       if ((p->p_flag & P_TRACED) == 0) {
+               if (KSI_TRAP_P(ksi)) {
+                       /*
+                        * If the signal was the result of a trap, only catch
+                        * the signal if it isn't masked and there is a
+                        * non-default non-ignore handler installed for it.
+                        * Otherwise take the default action.
+                        */
+                       if (!sigismember(&p->p_sigctx.ps_sigmask, signum) &&
+                           sigismember(&p->p_sigctx.ps_sigcatch, signum))
+                               action = SIG_CATCH;
+                       /*
+                        * If we are to take the default action, reset the
+                        * signal back to its defaults.
+                        */
+                       if (action == SIG_DFL) {
+                               sigdelset(&p->p_sigctx.ps_sigignore, signum);
+                               sigdelset(&p->p_sigctx.ps_sigcatch, signum);
+                               sigdelset(&p->p_sigctx.ps_sigmask, signum);
+                               SIGACTION(p, signum).sa_handler = SIG_DFL;
+                       }
+               } else {
+                       /*
+                        * If the signal is being ignored,
+                        * then we forget about it immediately.
+                        * (Note: we don't set SIGCONT in p_sigctx.ps_sigignore,
+                        * and if it is set to SIG_IGN,
+                        * action will be SIG_DFL here.)
+                        */
+                       if (sigismember(&p->p_sigctx.ps_sigignore, signum))
+                               return;
+                       if (sigismember(&p->p_sigctx.ps_sigmask, signum))
+                               action = SIG_HOLD;
+                       else if (sigismember(&p->p_sigctx.ps_sigcatch, signum))
+                               action = SIG_CATCH;
+               }
+               if (action == SIG_DFL) {
                        if (prop & SA_KILL && p->p_nice > NZERO)
                                p->p_nice = NZERO;