#ifndef MSG_H#define MSG_H#define LEN_MSG 1000#define LEN_DGRAM 1500#define LEN_NAME 64#include <semaphore.h>#include "ipmsg.h"#include <arpa/inet.h>//#include "comm.h"#include <pthread.h>#define INIT_MSGLIST(msglist)  { init_msg(&(msglist).head_msg,IPMSG_NOOPERATION); \					(msglist).tail_msg_ptr = &(msglist).head_msg;}					struct msg_info{	unsigned int version;	unsigned int packet_no;	char 		sender[LEN_NAME];	char 		host[LEN_NAME];	unsigned int command;	char	        extended[LEN_MSG];	struct sockaddr_in peer;	struct msg_info *next;	/*for extended use*/};struct msg_list{              struct msg_info head_msg;        struct msg_info *tail_msg_ptr;} ;extern struct msg_list ipmsg_msglist;extern sem_t NE_MSGLIST, NF_MSGLIST; extern pthread_mutex_t MUTEX_MSGLIST;extern int init_msg(struct msg_info *msg,unsigned int COMMAND);extern int parse_msg(char *buf,size_t buf_len,struct msg_info *msg);extern int form_msg(char *buf,size_t buf_len,struct msg_info *msg);extern struct msg_info * get_head_msg(struct msg_list *msglist);extern int add_tail_msg(struct msg_list *msglist,struct msg_info *msg);extern int free_msglist(struct msg_list *msglist);#endif  /*MSG_H*/