+static int client_append_fqdn_option(DHCPMessage *message, size_t optlen, size_t *optoffset,
+ const char *fqdn) {
+ uint8_t buffer[3 + DHCP_MAX_FQDN_LENGTH];
+ int r;
+
+ buffer[0] = DHCP_FQDN_FLAG_S | /* Request server to perform A RR DNS updates */
+ DHCP_FQDN_FLAG_E; /* Canonical wire format */
+ buffer[1] = 0; /* RCODE1 (deprecated) */
+ buffer[2] = 0; /* RCODE2 (deprecated) */
+
+ r = dns_name_to_wire_format(fqdn, buffer + 3, sizeof(buffer) - 3);
+ if (r > 0)
+ r = dhcp_option_append(message, optlen, optoffset, 0,
+ DHCP_OPTION_FQDN, 3 + r, buffer);
+
+ return r;
+}
+