pf_find_or_create_kruleset
struct pf_kruleset *pf_find_or_create_kruleset(const char *);
if ((ruleset = pf_find_or_create_kruleset(PF_RESERVED_ANCHOR)) == NULL) {
rs = pf_find_or_create_kruleset(anchor);
ruleset = pf_find_or_create_kruleset(path);
rs = pf_find_or_create_kruleset(trs->pfrt_anchor);
rs = pf_find_or_create_kruleset(tbl->pfrt_anchor);