pfctl: reduce duplicate code, fix typo/free correct buffer

[Klemens Nanni]

Two enhancements, one bug in `filteropts_to_rule()':

* Merge `once' handling from `anchorrule' and `pfrule'
* Remove/shorten duplicate code block
* Fix typo I introduced with r1.678 that frees the wrong buffer (twice)

OK?

Index: parse.y
===================================================================
RCS file: /cvs/src/sbin/pfctl/parse.y,v
retrieving revision 1.681
diff -u -p -r1.681 parse.y
--- parse.y     13 Jul 2018 08:41:15 -0000      1.681
+++ parse.y     15 Jul 2018 12:40:27 -0000
@@ -938,12 +938,6 @@ anchorrule : ANCHOR anchorname dir quick
                                YYERROR;
                        }
 
-                       if ($9.marker & FOM_ONCE) {
-                               yyerror("cannot specify 'once' "
-                                   "on anchors");
-                               YYERROR;
-                       }
-
                        decide_address_family($8.src.host, &r.af);
                        decide_address_family($8.dst.host, &r.af);
 
@@ -1560,15 +1554,6 @@ pfrule           : action dir logquick interface 
                        if (filteropts_to_rule(&r, &$8))
                                YYERROR;
 
-                       if ($8.marker & FOM_ONCE) {
-                               if (r.action == PF_MATCH) {
-                                       yyerror("can't specify once for "
-                                           "match rules");
-                                       YYERROR;
-                               }
-                               r.rule_flag |= PFRULE_ONCE;
-                       }
-
                        if ($8.flags.b1 || $8.flags.b2 || $7.src_os) {
                                for (proto = $6; proto != NULL &&
                                    proto->proto != IPPROTO_TCP;
@@ -5879,6 +5864,13 @@ rdomain_exists(u_int rdomain)
 int
 filteropts_to_rule(struct pf_rule *r, struct filter_opts *opts)
 {
+       if (opts->marker & FOM_ONCE) {
+               if (r->action != PF_PASS && r->action != PF_MATCH) {
+                       yyerror("'once' only applies to pass/block rules");
+                       return (1);
+               }
+               r->rule_flag |= PFRULE_ONCE;
+       }
 
        r->keep_state = opts->keep.action;
        r->pktrate.limit = opts->pktrate.limit;
@@ -5929,12 +5921,6 @@ filteropts_to_rule(struct pf_rule *r, st
        }
        if (opts->marker & FOM_SCRUB_TCP)
                r->scrub_flags |= PFSTATE_SCRUB_TCP;
-       if (opts->marker & FOM_PRIO) {
-               if (opts->prio == 0)
-                       r->prio = PF_PRIO_ZERO;
-               else
-                       r->prio = opts->prio;
-       }
        if (opts->marker & FOM_SETDELAY) {
                r->delay = opts->delay;
                r->rule_flag |= PFRULE_SETDELAY;
@@ -5948,12 +5934,8 @@ filteropts_to_rule(struct pf_rule *r, st
                r->scrub_flags |= PFSTATE_SETTOS;
                r->set_tos = opts->settos;
        }
-       if (opts->marker & FOM_PRIO) {
-               if (opts->prio == 0)
-                       r->prio = PF_PRIO_ZERO;
-               else
-                       r->prio = opts->prio;
-       }
+       if (opts->marker & FOM_PRIO)
+               r->prio = opts->prio ? opts->prio : PF_PRIO_ZERO;
        if (opts->marker & FOM_SETPRIO) {
                r->set_prio[0] = opts->set_prio[0];
                r->set_prio[1] = opts->set_prio[1];
@@ -5983,7 +5965,7 @@ filteropts_to_rule(struct pf_rule *r, st
                            "%d chars)", sizeof(r->pqname)-1);
                        return (1);
                }
-               free(opts->queues.qname);
+               free(opts->queues.pqname);
        }
 
        if (opts->fragment)