Fix infinite loop for undef function in @SIG{__WARN__,__DIE__}

diff --git a/util.c b/util.c
index 5329c5a..95d34e2 100644 (file)
--- a/util.c
+++ b/util.c
@@ -1181,18 +1181,26 @@ die(pat, va_alist)
     message = mess(pat, &args);
     va_end(args);
 
-    if (diehook && (cv = sv_2cv(diehook, &stash, &gv, 0)) && !CvDEPTH(cv)) {
-       dSP;
-       SV *msg = sv_2mortal(newSVpv(message, 0));
+    if (diehook) {
+       /* sv_2cv might call croak() */
+       SV *olddiehook = diehook;
+       ENTER;
+       SAVESPTR(diehook);
+       diehook = Nullsv;
+       cv = sv_2cv(olddiehook, &stash, &gv, 0);
+       LEAVE;
+       if (cv && !CvDEPTH(cv) && (CvROOT(cv) || CvXSUB(cv))) {
+           dSP;
+           SV *msg = sv_2mortal(newSVpv(message, 0));
 
-       PUSHMARK(sp);
-       EXTEND(sp, 1);
-       PUSHs(msg);
-       PUTBACK;
-       perl_call_sv((SV*)cv, G_DISCARD);
+           PUSHMARK(sp);
+           XPUSHs(msg);
+           PUTBACK;
+           perl_call_sv((SV*)cv, G_DISCARD);
 
-       /* It's okay for the __DIE__ hook to modify the message. */
-       message = SvPV(msg, na);
+           /* It's okay for the __DIE__ hook to modify the message. */
+           message = SvPV(msg, na);
+       }
     }
 
     restartop = die_where(message);
@@ -1226,17 +1234,19 @@ croak(pat, va_alist)
     message = mess(pat, &args);
     va_end(args);
     if (diehook) {
+       /* sv_2cv might call croak() */
        SV *olddiehook = diehook;
-       diehook = Nullsv;                 /* sv_2cv might call croak() */
+       ENTER;
+       SAVESPTR(diehook);
+       diehook = Nullsv;
        cv = sv_2cv(olddiehook, &stash, &gv, 0);
-       diehook = olddiehook;
-       if (cv && !CvDEPTH(cv)) {
+       LEAVE;
+       if (cv && !CvDEPTH(cv) && (CvROOT(cv) || CvXSUB(cv))) {
            dSP;
            SV *msg = sv_2mortal(newSVpv(message, 0));
 
            PUSHMARK(sp);
-           EXTEND(sp, 1);
-           PUSHs(msg);
+           XPUSHs(msg);
            PUTBACK;
            perl_call_sv((SV*)cv, G_DISCARD);
 
@@ -1292,16 +1302,17 @@ warn(pat,va_alist)
     va_end(args);
 
     if (warnhook) {
+       /* sv_2cv might call warn() */
        SV *oldwarnhook = warnhook;
-       warnhook = Nullsv;      /* sv_2cv might end up calling warn() */
+       ENTER;
+       SAVESPTR(warnhook);
+       warnhook = Nullsv;
        cv = sv_2cv(oldwarnhook, &stash, &gv, 0);
-       warnhook = oldwarnhook;
-       if (cv && !CvDEPTH(cv)) {
+       LEAVE;
+       if (cv && !CvDEPTH(cv) && (CvROOT(cv) || CvXSUB(cv))) {
            dSP;
-
            PUSHMARK(sp);
-           EXTEND(sp, 1);
-           PUSHs(sv_2mortal(newSVpv(message,0)));
+           XPUSHs(sv_2mortal(newSVpv(message,0)));
            PUTBACK;
            perl_call_sv((SV*)cv, G_DISCARD);
            return;
@@ -1637,12 +1648,7 @@ char     *mode;
     register I32 this, that;
     register I32 pid;
     SV *sv;
-    I32 doexec =
-#ifdef AMIGAOS
-       1;
-#else
-       strNE(cmd,"-");
-#endif
+    I32 doexec = strNE(cmd,"-");
 
 #ifdef OS2
     if (doexec) {