From: Nick Ing-Simmons <nik@tiuk.ti.com>
Date: Thu, 11 Jan 2001 20:57:44 +0000 (+0000)
Subject: Catch die in %SIG handler and unblock the signal before re-dying.
X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=commitdiff_plain;h=1b266415f383a85c93346bb15a7bdcac7f62eb77;p=p5sagit%2Fp5-mst-13.2.git

Catch die in %SIG handler and unblock the signal before re-dying.
This make Linux work _without_ sigsetjmp().
Turn off sigsetjmp() to see what else it does.
May need Configure probe for sigprocmask() if anything has sigaction()
but not sigprocmask().

p4raw-id: //depot/perlio@8407
---

diff --git a/mg.c b/mg.c
index ca06b89..a7566e3 100644
--- a/mg.c
+++ b/mg.c
@@ -2161,6 +2161,8 @@ Perl_sighandler(int sig)
     U32 flags = 0;
     I32 o_save_i = PL_savestack_ix;
     XPV *tXpv = PL_Xpv;
+    sigjmp_buf jmp;
+    Sighandler_t handler;
 
 #if defined(WIN32) && defined(PERL_IMPLICIT_CONTEXT)
     PERL_SET_THX(aTHXo);	/* fake TLS, see above */
@@ -2223,9 +2225,26 @@ Perl_sighandler(int sig)
     PUSHs(sv);
     PUTBACK;
 
-    call_sv((SV*)cv, G_DISCARD);
+    call_sv((SV*)cv, G_DISCARD|G_EVAL);
 
     POPSTACK;
+    if (SvTRUE(ERRSV)) {
+#ifdef HAS_SIGACTION
+	/* Handler "died", for example to get out of a restart-able read().
+	 * Before we re-do that on its behalf re-enable the signal which was
+	 * blocked by the system when we entered.
+	 */
+	sigset_t set;
+	sigemptyset(&set);
+	sigaddset(&set,sig);
+	sigprocmask(SIG_UNBLOCK, &set, NULL);
+#else
+	/* Not clear if this will work */
+	(void)rsignal(sig, SIG_IGN);
+	(void)rsignal(sig, PL_sighandlerp);
+#endif
+	Perl_die(aTHX_ Nullch);
+    }
 cleanup:
     if (flags & 1)
 	PL_savestack_ix -= 8; /* Unprotect save in progress. */
diff --git a/scope.h b/scope.h
index d45bd94..0ceb6ba 100644
--- a/scope.h
+++ b/scope.h
@@ -36,7 +36,7 @@
 #define SAVEt_PADSV		35
 
 #ifndef SCOPE_SAVES_SIGNAL_MASK
-#define SCOPE_SAVES_SIGNAL_MASK 1
+#define SCOPE_SAVES_SIGNAL_MASK 0
 #endif
 
 #define SSCHECK(need) if (PL_savestack_ix + need > PL_savestack_max) savestack_grow()