/* -*- c++ -*- */
/*
 * Copyright 2001,2003,2004 Free Software Foundation, Inc.
 * 
 * This file is part of GNU Radio
 * 
 * GNU Radio 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.
 * 
 * GNU Radio 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.
 * 
 * You should have received a copy of the GNU General Public License
 * along with GNU Radio; see the file COPYING.  If not, write to
 * the Free Software Foundation, Inc., 51 Franklin Street,
 * Boston, MA 02110-1301, USA.
 */

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
#include <ppio_ppdev.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <stdlib.h>
#include <iostream>
#include <errno.h>
#include <stdio.h>
#include <stdexcept>
#ifdef HAVE_LINUX_PPDEV_H
#include <sys/ioctl.h>
#include <linux/ppdev.h>
#include <linux/parport.h>
#include <sstream>
#else
// #warn "ppio_ppdev is not functional on this platform"
#endif

// These control port bits are active low.
// We toggle them so that this weirdness doesn't get get propagated
// through our interface.

static int CP_ACTIVE_LOW_BITS	= 0x0B;

// These status port bits are active low.
// We toggle them so that this weirdness doesn't get get propagated
// through our interface.

static int SP_ACTIVE_LOW_BITS	= 0x80;

#ifndef HAVE_LINUX_PPDEV_H		// use stubs

ppio_ppdev::ppio_ppdev (int which)
{
  std::cerr << "ppio_ppdev: Not implemented on this platform\n";
  throw std::runtime_error ("not implmeneted");
}

ppio_ppdev::~ppio_ppdev ()
{
}

void 
ppio_ppdev::write_data (unsigned char v)
{
}

unsigned char
ppio_ppdev::read_data ()
{
  return 0;
}

void 
ppio_ppdev::write_control (unsigned char v)
{
}

unsigned char
ppio_ppdev::read_control ()
{
  return 0;
}

unsigned char
ppio_ppdev::read_status ()
{
  return 0;
}

void
ppio_ppdev::lock ()
{
}

void
ppio_ppdev::unlock ()
{
}

#else		

// The real code...

ppio_ppdev::ppio_ppdev (int which)
{
  std::ostringstream filename;
  filename << "/dev/parport" << which;
  const char *c_filename = filename.str().c_str();

  if ((d_fd = open (c_filename, O_RDWR)) < 0){
    int my_errno = errno;
    perror (c_filename);
    if (my_errno == ENOENT){
      std::cerr << "Does the device file " << c_filename << " exist?\n";
      std::cerr << "If not, as root execute: \n";
      std::cerr << "  # mknod " << c_filename << " c 99 0\n";
      std::cerr << "  # chmod 666 " << c_filename << std::endl;
    }
    throw std::runtime_error ("open");
  }

  int mode = IEEE1284_MODE_COMPAT;
  if (ioctl (d_fd, PPSETMODE, &mode) != 0){
    perror ("ppio_ppdev: PPSETMODE");
    close (d_fd);
    throw std::runtime_error ("PPSETMODE");
  }
}

ppio_ppdev::~ppio_ppdev ()
{
  close (d_fd);
}


void 
ppio_ppdev::write_data (unsigned char v)
{
  if (ioctl (d_fd, PPWDATA, &v) != 0){
    perror ("ppio_ppdev: PPWDATA");
    throw std::runtime_error ("PPWDATA");
  }
}

unsigned char
ppio_ppdev::read_data ()
{
  unsigned char v;

  if (ioctl (d_fd, PPRDATA, &v) != 0){
    perror ("ppio_ppdev: PPRDATA");
    throw std::runtime_error ("PPRDATA");
  }
  return v;
}

void 
ppio_ppdev::write_control (unsigned char v)
{
  unsigned char ctrl = v ^ CP_ACTIVE_LOW_BITS;
  if (ioctl (d_fd, PPWCONTROL, &ctrl) != 0){
    perror ("ppio_ppdev: PPWCONTROL");
    throw std::runtime_error ("PPWCONTROL");
  }
}

unsigned char
ppio_ppdev::read_control ()
{
  unsigned char ctrl;
  if (ioctl (d_fd, PPRCONTROL, &ctrl) != 0){
    perror ("ppio_ppdev: PPRCONTROL");
    throw std::runtime_error ("PPRCONTROL");
  }

  return ctrl ^ CP_ACTIVE_LOW_BITS;
}

unsigned char
ppio_ppdev::read_status ()
{
  unsigned char status;
  if (ioctl (d_fd, PPRSTATUS, &status) != 0){
    perror ("ppio_ppdev: PPRSTATUS");
    throw std::runtime_error ("PPRSTATUS");
  }

  return status ^ SP_ACTIVE_LOW_BITS;
}

void
ppio_ppdev::lock ()
{
  if (ioctl (d_fd, PPCLAIM) != 0){
    perror ("ppio_ppdev: PPCLAIM");
    throw std::runtime_error ("PPCLAIM");
  }
}

void
ppio_ppdev::unlock ()
{
  if (ioctl (d_fd, PPRELEASE) != 0){
    perror ("ppio_ppdev: PPRELEASE");
    throw std::runtime_error ("PPRELEASE");
  }
}

#endif

ppio_ppdev_sptr
make_ppio_ppdev (int which)
{
  return ppio_ppdev_sptr (new ppio_ppdev (which));
}