#include <stdio.h>
#include <errno.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <string.h>
#include <stdlib.h>
#include <unistd.h>

int port = 8000;
int one = 1;

struct sockaddr_in lst_a;
int lst_fd, srv_fd;
int lbuf;

char buf[1024];

void die_msg(const char *msg)
{
	if (msg)
		fprintf(stderr, "%s\n", msg);
	exit(1);
}

void die_err(const char *msg)
{
	perror(msg);
	exit(1);
}

int main(int argc, char **argv)
{
	if (argc > 1)
		port = atol(argv[1]);

	if ((lst_fd = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP)) == -1)
		die_err("socket");

	if ((setsockopt(lst_fd, SOL_SOCKET, SO_REUSEADDR, &one, sizeof(one))) == -1)
		die_err("setsockopt");

	bzero((char *)&lst_a, sizeof(lst_a));
	lst_a.sin_family      = AF_INET;
	lst_a.sin_addr.s_addr = htonl(INADDR_ANY);
	lst_a.sin_port        = htons(port);
	if (bind(lst_fd, (struct sockaddr *)&lst_a, sizeof(lst_a)) == -1)
		die_err("bind");

	if (listen(lst_fd, 1) == -1)
		die_err("listen");

	if ((srv_fd = accept(lst_fd, NULL, NULL)) == -1)
		die_err("accept");

	fprintf(stderr, "accept() returns %d\n", srv_fd);

	if ((lbuf = recv(srv_fd, buf, sizeof(buf), 0)) == -1)
		die_err("recv");

	fprintf(stderr, "recv() returns %d\n", lbuf);

	/* now let's pretend some processing time. If the sender sends any more
	 * data during the sleep(), it causes the response to be truncated.
	 */
	sleep(1);

	send(srv_fd, "block1\n", 7, 0);
	send(srv_fd, "block2\n", 7, 0);
	//shutdown(srv_fd, SHUT_WR);
	close(srv_fd);
	return 0;
}