SIP_HANDLER
SIP_HANDLER("INVITE", process_invite_request, process_invite_response),
SIP_HANDLER("UPDATE", process_sdp, process_update_response),
SIP_HANDLER("ACK", process_sdp, NULL),
SIP_HANDLER("PRACK", process_sdp, process_prack_response),
SIP_HANDLER("BYE", process_bye_request, NULL),
SIP_HANDLER("REGISTER", process_register_request, process_register_response),