Don't quote NL in panic messages

bin/varnishd/mgt/mgt_child.c

@@ -117,7 +117,8 @@ mgt_panic_record(pid_t r)
 	VTIM_format(VTIM_real(), time_str);
 	VSB_printf(child_panic, "Panic at: %s\n", time_str);
 	VSB_quote(child_panic, heritage.panic_str,
-	    strnlen(heritage.panic_str, heritage.panic_str_len), 0);
+	    strnlen(heritage.panic_str, heritage.panic_str_len),
+	    VSB_QUOTE_NONL);
 	AZ(VSB_finish(child_panic));
 	MGT_complain(C_ERR, "Child (%jd) %s",
 	    (intmax_t)r, VSB_data(child_panic));

include/vsb.h

@@ -75,6 +75,7 @@ int		 VSB_finish(struct vsb *);
 char		*VSB_data(const struct vsb *);
 ssize_t		 VSB_len(const struct vsb *);
 void		 VSB_delete(struct vsb *);
+#define VSB_QUOTE_NONL	1
 void		 VSB_quote(struct vsb *s, const char *p, int len, int how);
 void		 VSB_indent(struct vsb *, int);
 #ifdef __cplusplus

lib/libvarnish/vsb.c

@@ -519,7 +519,10 @@ VSB_quote(struct vsb *s, const char *p, int len, int how)
 			(void)VSB_putc(s, *q);
 			break;
 		case '\n':
-			(void)VSB_cat(s, "\\n");
+			if (how & VSB_QUOTE_NONL)
+				(void)VSB_cat(s, "\n");
+			else
+				(void)VSB_cat(s, "\\n");
 			break;
 		case '\r':
 			(void)VSB_cat(s, "\\r");