#include <unistd.h>
#include <stdlib.h>
#include <stdio.h>
#include <sys/select.h>
#include <sys/ioctl.h>
#include <errno.h>
#include <termios.h>

static struct termios term_attributes;

int 
tty_cbreak (int fd, struct termios *orig)
{
  struct termios buf;
   
  if (tcgetattr (fd, &buf) < 0)
    return -1;

  /* Save the original state, for resetting later */
  *orig = buf;
      
  buf.c_lflag &= ~(ECHO | ICANON);
  buf.c_iflag &= ~(ICRNL | INLCR);
  buf.c_cc[VMIN] = 1;
  buf.c_cc[VTIME] = 0;

#if defined (VLNEXT) && defined (_POSIX_VDISABLE)
  buf.c_cc[VLNEXT] = _POSIX_VDISABLE;
#endif

#if defined (VDSUSP) && defined (_POSIX_VDISABLE)
  buf.c_cc[VDSUSP] = _POSIX_VDISABLE;
#endif

  if (tcsetattr (fd, TCSAFLUSH, &buf) < 0)
    return -1;

  return 0;   
}

int 
tty_set_attributes (int fd, struct termios *buf)
{
  if (tcsetattr (fd, TCSAFLUSH, buf) < 0)
    return -1;
      
  return 0;   
}

int
user_input_loop ()
{
   fprintf (stderr, "In user_input_loop\r\n");
   return 0;
}

static int
main_loop (void)
{
  fd_set rset;
  int max = STDIN_FILENO;
  int val;

  for (;;)
  {
     /* Reset the fd_set, and watch for input from GDB or stdin */
     FD_ZERO (&rset);

     FD_SET (STDIN_FILENO, &rset);

     /* Wait for input */
     val =select (max + 1, &rset, NULL, NULL, NULL);
     fprintf (stderr, "Select return value:%d\r\n", val);
     if (val == -1)
     {
        if (errno == EINTR)
           continue;
        else
        {
           fprintf (stderr, __FILE__, __LINE__,
                 "select failed: %s", strerror (errno));
           return -1;
        }
     }

     /* Input received:  Handle it */
     if (FD_ISSET (STDIN_FILENO, &rset)) {
        if (user_input_loop () == -1)
           return -1;
        return 0;
     }
  }

  return 0;
}

int
main (int argc, char *argv[])
{
  if (tty_cbreak (STDIN_FILENO, &term_attributes) == -1)
    {
      fprintf (stderr, __FILE__, __LINE__, "tty_cbreak error");
      exit (-1);
    }

  /* Enter main loop */
  main_loop ();

  if (tty_set_attributes (STDIN_FILENO, &term_attributes) == -1)
    fprintf (stderr, __FILE__, __LINE__, "tty_reset error");

  return 0;
}