#include <sys/types.h>
#include <sys/time.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <netdb.h>
#include <stdio.h>
#include <uprobe.h>

void printsockaddr(struct sockaddr_in *arg)
{
    struct hostent *hp;
    printf("  sockaddr_in: ");
    printf("Domain=%d, ", arg->sin_family);
    hp=gethostbyaddr(&(arg->sin_addr), sizeof(arg->sin_addr), AF_INET);
    printf("Hostname=%s, ", hp->h_name);
    printf("Port=%d, ", ntohs(arg->sin_port));
    printf("Address=%s,\n", inet_ntoa(arg->sin_addr));
}

help_msg()
{
	printf("format: coord -[d] sec usec tosec tousec pktsize sender receiver portno\n");
	printf("          option: d set debug mode\n");
}

main(argc, argv)
int argc;
char *argv[];
{
	int sock; 
	struct sockaddr_in dst;
	struct sockaddr_in src;
	struct sockaddr_in coord;
	struct timeval timeout;
	struct timeval starttime;
	char coordinator[100];
	char sender[100];
	char receiver[100];
	struct hostent *hp, *gethostbyname();
	Union Uprobemsg upmsg;
	struct Uprobereq upreq;
	struct Uprobereport uprep;
	int sequenceno = 0;

	int n;
	char toBuf[1024];
	char fromBuf[1024];
	char buf[1024];
	char hostname[64];
	extern char *optarg;
	extern int   optind;
	int option_exist = 0;
	int c;
	int debug = 0;
	int toPort_no;
	int length;
	int flag = 1;

	fd_set readfds;
	struct timeval to;
	int state = 1;
	int retry = 3;
	int r;
	int maxfdpl;
	int i;

	/* process command line args */
	while ((c=getopt(argc,argv,"d:")) != EOF)
	{
		option_exist = 1;
		switch(c)
		{
		case 'd':
			debug = 1;
			if (debug)
				printf("turn on debug mode.\n");
			break;

		case '?':
			help_msg();
			exit (1);
		default:
			fprintf (stderr, "unrecognized arg >%s<\n", optarg);
			help_msg();
			exit (1);
		}
	}

	starttime.tv_sec = atol(argv[optind++]);
	starttime.tv_usec = atol(argv[optind++]);
	timeout.tv_sec = atol(argv[optind++]);
	timeout.tv_usec = atol(argv[optind++]);
	if (gethostname(coordinator, sizeof(coordinator)) {
		perror("gethostname error!");
		exit(3);
	}
	strcpy(sender, argv[optind++]);
	strcpy(receiver, argv[optind++]);
	printf("starttime is set to %d sec %d usec\n", 
		starttime.tv_sec, starttime.tv_usec);
	printf("timeout is set to %d sec %d usec\n", 
		timeout.tv_sec, timeout.tv_usec);
	printf("coordinator is %s\n", 
		coordinator);
	printf("sender is %s\n", 
		sender);
	printf("receiver is %s\n", 
		receiver);
	if ((toPort_no = atoi(argv[optind])) < 1025) toPort_no = 1025;

	printf("port_no=%d\n", toPort_no);


	/* create socket from which to read */
	sock = socket(AF_INET, SOCK_DGRAM, 0);
	if (sock < 0) {
		perror("opening datagram socket");
		exit(1);
	}
	/* create name structure using IPPORT_USERRESERVED  */
	coord.sin_family = AF_INET;
	coord.sin_addr.s_addr = IPPORT_USERRESERVED;
	coord.sin_port = htons(toPort_no);  
	/* port no. < 1024 IPPORT_RESERVED is for privillege process */
	/* here just initialized it, it will be assigned value after call */
	/* getsockname() */
	if (bind(sock, &coord, sizeof(struct sockaddr_in))) {
		perror("binding name to datagram socket");
		exit(1);
	}
	length = sizeof(coord);
	if (getsockname(sock, &coord, &length)) {
		perror("getting socket name");
		exit(1);
	}
	/* Find assigned port value and print out. */
	printf("socket has port #%d\n", ntohs(from.sin_port));

	/* construct name of the socket to send to 
	 * gethostbyname() returns a structure including the network address
	 * of the specified host from /etc/hosts. The port number is taken from
	 * the cmd line
	 * create name structure for the UNIX domain socket 
	 * use the name from cmd argument 
	 */
	hp = gethostbyname(coordinator);
	if (hp == 0) {
		fprintf(stderr, "%s: unknown host", receiver);
		exit(2);
	}
	bcopy(hp->h_addr, &coord.sin_addr, hp->h_length);
	coord.sin_family = AF_INET;
	coord.sin_port = htons(toPort_no);
	hp = gethostbyname(receiver);
	if (hp == 0) {
		fprintf(stderr, "%s: unknown host", receiver);
		exit(2);
	}
	bcopy(hp->h_addr, &dst.sin_addr, hp->h_length);
	dst.sin_family = AF_INET;
	dst.sin_port = htons(toPort_no);
	hp = gethostbyname(sender);
	if (hp == 0) {
		fprintf(stderr, "%s: unknown host", sender);
		exit(2);
	}
	bcopy(hp->h_addr, &src.sin_addr, hp->h_length);
	src.sin_family = AF_INET;
	src.sin_port = htons(toPort_no);
	upr.msgtype = UPROBEREQ;
	upr.sequence = sequenceno++;
	bcopy(&coord, &upr.coord, sizeof(coord));
	bcopy(&src, &upr.src, sizeof(src));
	bcopy(&dst, &upr.dst, sizeof(dst));
	printf("upr.coord value is\n");
	printsockaddr(&upr.coord);
	printf("upr.src value is\n");
	printsockaddr(&upr.src);
	printf("upr.dst value is\n");
	printsockaddr(&upr.dst);
	

	while (flag) {
	printf("Enter state %d\n", state);
	switch(state) {
	case 1:
		printf("Enter the message=");
		gets(toBuf);
		if (strcmp(toBuf, "$") == 0) state = 4;
		else {
			state = 2;
			r = retry;
			}
		break;
	case 2:
		if (sendto(sock, toBuf, strlen(toBuf), 0, &to, sizeof(to)) < 0) 
			perror("sending datagram message");
		state = 3;
		break;
	case 3:
		FD_ZERO(&readfds);
		FD_SET(0, &readfds);
		FD_SET(sock, &readfds);
		maxfdpl = sock+1;
		if ((i=select(maxfdpl, &readfds, 0, 0, &timeout)) < 0)  {
			perror("select error"); exit(1);
		}
		if (i==0) {
			printf("timeout!");
			if (r == 0) state = 4;
			else {
				r--;
				printf("retry %d\n", r);
				state = 2;
			}
		}
		if (FD_ISSET(0, &readfds)) {
			gets(buf);
			if (strcmp(buf, "$") == 0) state = 4;
			else {
				printf("user input =%s != $, neglect it\n", buf);
			}
		}
		if (FD_ISSET(sock, &readfds)) {
			n = recv(sock, fromBuf, sizeof(fromBuf), 0);
			if (n <= 0) {
				perror("error in recv()"); exit(1);
			}
			printf("received ack =%s\n", fromBuf);
			state = 1;
		}
		break;
	case 4:
		flag = 0;
		printf("exit to while loop\n");
		break;
	default:
		printf("incorrect state!\n");
		flag = 0;
		break;
	}
	}
	close(sock);
}