X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=blobdiff_plain;f=mg.c;h=eee140bdf58f796f833e5df8795f9ec3f2ed5cac;hb=1bb0a50fd869bf3d7f152d29ec8c8119703266a1;hp=941338b644c61b4313dc7a01895c18f1bb2b57c0;hpb=e69880a56d80785fbe5600b4e7dabf583188c526;p=p5sagit%2Fp5-mst-13.2.git

diff --git a/mg.c b/mg.c
index 941338b..eee140b 100644
--- a/mg.c
+++ b/mg.c
@@ -1,6 +1,7 @@
 /*    mg.c
  *
- *    Copyright (c) 1991-2003, Larry Wall
+ *    Copyright (C) 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999,
+ *    2000, 2001, 2002, 2003, by Larry Wall and others
  *
  *    You may distribute under the terms of either the GNU General Public
  *    License or the Artistic License, as specified in the README file.
@@ -133,6 +134,12 @@ Perl_mg_get(pTHX_ SV *sv)
 
 	if (!(mg->mg_flags & MGf_GSKIP) && vtbl && vtbl->svt_get) {
 	    CALL_FPTR(vtbl->svt_get)(aTHX_ sv, mg);
+
+	    /* guard against sv having been freed */
+	    if (SvTYPE(sv) == SVTYPEMASK) {
+		Perl_croak(aTHX_ "Tied variable freed while still in use");
+	    }
+
 	    /* Don't restore the flags for this entry if it was deleted. */
 	    if (mg->mg_flags & MGf_GSKIP)
 		(SSPTR(mgs_ix, MGS *))->mgs_flags = 0;
@@ -1069,7 +1076,7 @@ Perl_magic_getsig(pTHX_ SV *sv, MAGIC *mg)
     STRLEN n_a;
     /* Are we fetching a signal entry? */
     i = whichsig(MgPV(mg,n_a));
-    if (i) {
+    if (i > 0) {
     	if(PL_psig_ptr[i])
     	    sv_setsv(sv,PL_psig_ptr[i]);
     	else {
@@ -1120,7 +1127,7 @@ Perl_magic_clearsig(pTHX_ SV *sv, MAGIC *mg)
 	I32 i;
 	/* Are we clearing a signal entry? */
 	i = whichsig(s);
-	if (i) {
+	if (i > 0) {
 #ifdef HAS_SIGPROCMASK
 	    sigset_t set, save;
 	    SV* save_sv;
@@ -1267,7 +1274,7 @@ Perl_magic_setsig(pTHX_ SV *sv, MAGIC *mg)
     }
     else {
 	i = whichsig(s);	/* ...no, a brick */
-	if (!i) {
+	if (i < 0) {
 	    if (ckWARN(WARN_SIGNAL))
 		Perl_warner(aTHX_ packWARN(WARN_SIGNAL), "No such signal: SIG%s", s);
 	    return 0;
@@ -2433,7 +2440,7 @@ Perl_whichsig(pTHX_ char *sig)
 {
     register char **sigv;
 
-    for (sigv = PL_sig_name+1; *sigv; sigv++)
+    for (sigv = PL_sig_name; *sigv; sigv++)
 	if (strEQ(sig,*sigv))
 	    return PL_sig_num[sigv - PL_sig_name];
 #ifdef SIGCLD
@@ -2444,7 +2451,7 @@ Perl_whichsig(pTHX_ char *sig)
     if (strEQ(sig,"CLD"))
 	return SIGCHLD;
 #endif
-    return 0;
+    return -1;
 }
 
 #if !defined(PERL_IMPLICIT_CONTEXT)