/* serial.c
 * This file contains the function sgetch () which reads a
 * character from stdin while listening to the serial port.
 */

/* Copyright (C) 1999 Jonathan duSaint
 *
 * This file is part of Tap, an interactive program for reading and
 * writing data to the serial port to facilitate the reverse
 * engineering of communication protocols.
 *
 * Tap is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2, or (at your option)
 * any later version.
 *
 * Tap is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
 * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public
 * License for more details.
 *
 * The GNU General Public License is generally kept in a file called
 * COPYING or LICENSE.  If you do not have a copy of the license, write
 * to the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
 */

#include "tap.h"

/* This function reads a fixed number of chars from the serial port
 * and then writes it to wherever it needs to go. */
void
read_serial_data (void)
{
  int data_read;

  data_read = read (serial_port_fd, serial_buffer, serial_buffer_size);

  write_to_output_window (data_read);
  write_to_capture_register (data_read);
  write_to_capture_file (data_read);
}

/* This function reads a character from stdin while listening to
 * the serial port (if one is open).
 */
int
sgetch (void)
{
  fd_set readfs;
  int ret, highest_port = 1, fds;

  for (;;)
    {
      /* set focus to input_window */
      wrefresh (input_window);

      FD_ZERO (&readfs);
      FD_SET (0, &readfs); /* always listen to stdin */

      if (port != NULL)
	{ /* if a serial port is open */
	  FD_SET (serial_port_fd, &readfs);
	  highest_port = serial_port_fd + 1;
	}

      fds = select (highest_port, &readfs, NULL, NULL, NULL);

      if (fds < 0)
	{ /* error */
	  /* for now just ignore it */
	}
      else if (fds > 0)
	{
	  if (FD_ISSET (0, &readfs))
	    {
	      ret = wgetch (input_window);
	      return (ret);
	    }
	  else if (FD_ISSET (serial_port_fd, &readfs))
	    {
	      read_serial_data (); /* and reloop */
	    }
	}
    }

  return (ret);
}