WIP lib/rules: consider multiple tags variants when answering

diff --git a/lib/rules/api.c b/lib/rules/api.c
index 238eeda780d22bb3a32be91ede96a027af8d252e..a656eb7e907b62d87a1446e27908d7340c534d9d 100644 (file)
--- a/lib/rules/api.c
+++ b/lib/rules/api.c
@@ -334,20 +334,20 @@ int rule_local_data_answer(struct kr_query *qry, knot_pkt_t *pkt)
                for (int i = 0; i < 1 + want_CNAME; ++i) {
                        memcpy(key_data + KEY_DNAME_END_OFFSET + 2, &types[i], sizeof(rrtype));
                        knot_db_val_t val;
-                       // LATER: use cursor to iterate over multiple rules on the same key,
-                       // testing tags on each
-                       ret = ruledb_op(read, &key, &val, 1);
-                       switch (ret) {
-                               case -ENOENT: continue;
-                               case 0: break;
-                               default: return kr_error(ret);
-                       }
-                       if (!kr_rule_consume_tags(&val, qry->request)) continue;
+                       // Multiple variants are possible, with different tags.
+                       for (ret = ruledb_op(it_first, &key, &val);
+                                       ret == 0;
+                                       ret = ruledb_op(it_next, &val)) {
+                               if (!kr_rule_consume_tags(&val, qry->request))
+                                       continue;
 
-                       // We found a rule that applies to the dname+rrtype+req.
-                       ret = answer_exact_match(qry, pkt, types[i],
-                                                val.data, val.data + val.len);
-                       return ret ? kr_error(ret) : RET_ANSWERED;
+                               // We found a rule that applies to the dname+rrtype+req.
+                               ret = answer_exact_match(qry, pkt, types[i],
+                                                        val.data, val.data + val.len);
+                               return ret ? kr_error(ret) : RET_ANSWERED;
+                       }
+                       if (kr_fails_assert(ret == 0 || ret == -ENOENT))
+                               return kr_error(ret);
                }
 
                /* Find the closest zone-like apex that applies.
@@ -714,15 +714,14 @@ static int answer_zla_redirect(struct kr_query *qry, knot_pkt_t *pkt, const char
        knot_db_val_t key = local_data_key(&rrs, key_data, ruleset_name);
 
        knot_db_val_t val;
-       ret = ruledb_op(read, &key, &val, 1);
-       switch (ret) {
-               case -ENOENT: goto nodata;
-               case 0: break;
-               default: return ret;
+       // Multiple variants are possible, with different tags.
+       for (ret = ruledb_op(it_first, &key, &val); ret == 0; ret = ruledb_op(it_next, &val)) {
+               if (kr_rule_consume_tags(&val, qry->request))
+                       return answer_exact_match(qry, pkt, qry->stype,
+                                                       val.data, val.data + val.len);
        }
-       if (kr_rule_consume_tags(&val, qry->request)) // found a match
-               return answer_exact_match(qry, pkt, qry->stype,
-                                               val.data, val.data + val.len);
+       if (ret && ret != -ENOENT)
+               return ret;
 
 nodata: // Want NODATA answer (or NOERROR if it hits apex SOA).
        // Start constructing the (pseudo-)packet.
@@ -984,6 +983,8 @@ int kr_view_select_action(const struct kr_request *req, knot_db_val_t *selected)
                                }
                        }
                        // We certainly have a matching key (join of various sub-cases).
+                       // LATER: we'd iterate on this key's entries and find one
+                       //   that matches additional conditions (optional ones in future)
                        if (kr_log_is_debug(RULES, NULL)) {
                                // it's complex to get zero-terminated string for the action
                                char act_0t[val.len + 1];