#include <ostream.h>
#include <errno.h>
#include <stdlib.h>
#include <unistd.h>
#include <fcntl.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/ioctl.h>
#include <netinet/in.h>

void
my_perror(const char* msg)
{
    cerr << msg << ": "
	<< strerror(errno) << " (" << errno << ")" << endl;
}

void
waitSelect(int fd)
{
    
    fd_set wrfds;
    FD_ZERO(&wrfds);
    FD_SET(fd, &wrfds);

    int r = ::select(fd + 1, NULL, &wrfds, NULL, NULL);
    
    cerr << "select = " << r << endl;
    cerr << "fd_isset = " << (int)(FD_ISSET(fd, &wrfds)) << endl;
    
    if (r <= 0) {
	my_perror("select");
	exit(1);
    }
}

int
main(int argc, char* argv[])
{
    int fd, r;
    
    if (argc < 2) {
	cerr << "Usage: connect <port> [nonblock]" << endl;
	exit(2);
    }
    
    bool nonblock = (argc > 2);
    int port = ::atoi(argv[1]);

    while (1) {

	cerr << "sleep..." << endl;
	sleep(1);
	
	cerr << "starting connect" << endl;

	fd = ::socket(PF_INET, SOCK_STREAM, 0);
	if (fd == -1) {
	    my_perror("socket");
	    exit(1);
	}

	cerr << "fd = " << fd << endl;

	if (nonblock) {
	    ::fcntl(fd, F_SETFL, ::fcntl(fd, F_GETFL) | O_NONBLOCK);
	}

	sockaddr_in sin;
	sin.sin_family = AF_INET;
	sin.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
	sin.sin_port = htons(port);
	::memset(sin.sin_zero, 0, sizeof(sin.sin_zero));

	if (::connect(fd, (sockaddr*)&sin, sizeof(sin)) != 0) {
	    if (errno != EINPROGRESS) {
		my_perror("connect");
		::close(fd);
		continue;
	    }

	    my_perror("connect");

	    cerr << "waiting for connect..." << endl;
	    
	    waitSelect(fd);

	    cerr << "waiting over" << endl;
	    
	    int sockError = 0;
	    socklen_t sockErrorLen = sizeof(sockError);
	    if (::getsockopt(fd, SOL_SOCKET, SO_ERROR,
		&sockError, &sockErrorLen) == -1) {
		my_perror("getsockopt SO_ERROR");
		exit(1);
	    }

	    if (sockError != 0) {
		cerr << "connect: " << strerror(sockError)
		    << " (" << sockError << ")" << endl;

		::close(fd);
		continue;
	    }

	    cerr << "connected" << endl;

	} else {
	    cerr << "connected straight away" << endl;
	}

	::fcntl(fd, F_SETFL, ::fcntl(fd, F_GETFL) & ~O_NONBLOCK);

	while (1) {
	    char buffer[256];
	    r = ::read(fd, buffer, sizeof(buffer));
	    
	    cerr << "read = " << r << endl;
		// blocking read from socket
	    
	    if (r <= 0)
		break;
	}

	::close(fd);
	    
	if (r < 0)
	    my_perror("read");
	else
	    cerr << "EOF" << endl;

    }
}