#ifndef _SIP_CTRL#define _SIP_CTRL#include"sip_message.h"#include"sdp.h"int SendRegister(char* msg, char* username,  char* sevr_addr);int SendUnRegister(char* msg);int SendInvite(char* msg, char* username, char* called, int rtpport);int SendTrying(char* msg);int SendRinging(char* msg);int SendOK(char* msg);int SendAck(char* msg);int SendBye(char* msg);int SendCancel(char* msg);int SendBusy(char* msg, char* r_msg);int SendRequestTerminate(char* msg);int RecvRequest(enum method request, char* msg, RECV_INFO* info);int RecvResponse(enum method response, char* msg, RECV_INFO* info);int RecvInvite(char* msg, RECV_INFO* info);int RecvOK(char* msg, RECV_INFO* info);int RecvAck(char* msg, RECV_INFO* info);int RecvBye(char* msg, RECV_INFO* info);int RecvCancel(char* msg, RECV_INFO* info);void Make_Via(char* via, char* addr, int seq);void save_message(char* msg, SAVE_MSG* s_msg);void Finish(SAVE_MSG* msg, STACK_INFO* info);#endif