+/* ofputil_role_request */
+
+/* Decodes the OpenFlow "role request" or "role reply" message in '*oh' into
+ * an abstract form in '*rr'. Returns 0 if successful, otherwise an
+ * OFPERR_* value. */
+enum ofperr
+ofputil_decode_role_message(const struct ofp_header *oh,
+ struct ofputil_role_request *rr)
+{
+ struct ofpbuf b;
+ enum ofpraw raw;
+
+ ofpbuf_use_const(&b, oh, ntohs(oh->length));
+ raw = ofpraw_pull_assert(&b);
+
+ if (raw == OFPRAW_OFPT12_ROLE_REQUEST ||
+ raw == OFPRAW_OFPT12_ROLE_REPLY) {
+ const struct ofp12_role_request *orr = b.l3;
+
+ if (orr->role != htonl(OFPCR12_ROLE_NOCHANGE) &&
+ orr->role != htonl(OFPCR12_ROLE_EQUAL) &&
+ orr->role != htonl(OFPCR12_ROLE_MASTER) &&
+ orr->role != htonl(OFPCR12_ROLE_SLAVE)) {
+ return OFPERR_OFPRRFC_BAD_ROLE;
+ }
+
+ rr->role = ntohl(orr->role);
+ if (raw == OFPRAW_OFPT12_ROLE_REQUEST
+ ? orr->role == htonl(OFPCR12_ROLE_NOCHANGE)
+ : orr->generation_id == htonll(UINT64_MAX)) {
+ rr->have_generation_id = false;
+ rr->generation_id = 0;
+ } else {
+ rr->have_generation_id = true;
+ rr->generation_id = ntohll(orr->generation_id);
+ }
+ } else if (raw == OFPRAW_NXT_ROLE_REQUEST ||
+ raw == OFPRAW_NXT_ROLE_REPLY) {
+ const struct nx_role_request *nrr = b.l3;
+
+ BUILD_ASSERT(NX_ROLE_OTHER + 1 == OFPCR12_ROLE_EQUAL);
+ BUILD_ASSERT(NX_ROLE_MASTER + 1 == OFPCR12_ROLE_MASTER);
+ BUILD_ASSERT(NX_ROLE_SLAVE + 1 == OFPCR12_ROLE_SLAVE);
+
+ if (nrr->role != htonl(NX_ROLE_OTHER) &&
+ nrr->role != htonl(NX_ROLE_MASTER) &&
+ nrr->role != htonl(NX_ROLE_SLAVE)) {
+ return OFPERR_OFPRRFC_BAD_ROLE;
+ }
+
+ rr->role = ntohl(nrr->role) + 1;
+ rr->have_generation_id = false;
+ rr->generation_id = 0;
+ } else {
+ NOT_REACHED();
+ }
+
+ return 0;
+}
+
+/* Returns an encoded form of a role reply suitable for the "request" in a
+ * buffer owned by the caller. */
+struct ofpbuf *
+ofputil_encode_role_reply(const struct ofp_header *request,
+ const struct ofputil_role_request *rr)
+{
+ struct ofpbuf *buf;
+ enum ofpraw raw;
+
+ raw = ofpraw_decode_assert(request);
+ if (raw == OFPRAW_OFPT12_ROLE_REQUEST) {
+ struct ofp12_role_request *orr;
+
+ buf = ofpraw_alloc_reply(OFPRAW_OFPT12_ROLE_REPLY, request, 0);
+ orr = ofpbuf_put_zeros(buf, sizeof *orr);
+
+ orr->role = htonl(rr->role);
+ orr->generation_id = htonll(rr->have_generation_id
+ ? rr->generation_id
+ : UINT64_MAX);
+ } else if (raw == OFPRAW_NXT_ROLE_REQUEST) {
+ struct nx_role_request *nrr;
+
+ BUILD_ASSERT(NX_ROLE_OTHER == OFPCR12_ROLE_EQUAL - 1);
+ BUILD_ASSERT(NX_ROLE_MASTER == OFPCR12_ROLE_MASTER - 1);
+ BUILD_ASSERT(NX_ROLE_SLAVE == OFPCR12_ROLE_SLAVE - 1);
+
+ buf = ofpraw_alloc_reply(OFPRAW_NXT_ROLE_REPLY, request, 0);
+ nrr = ofpbuf_put_zeros(buf, sizeof *nrr);
+ nrr->role = htonl(rr->role - 1);
+ } else {
+ NOT_REACHED();
+ }
+
+ return buf;
+}
+\f