modem.cpp

/*
    KMLOCfg
 
    A utility to configure the ELSA MicroLink(tm) Office modem.
 
    Copyright (C) 2000 Oliver Gantz <Oliver.Gantz@epost.de>
 
    This program 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 of the License, or
    (at your option) any later version.
 
    This program 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 this program; if not, write to the Free Software
    Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
 
    ------
    ELSA and MicroLink are trademarks of ELSA AG, Aachen.
*/
 
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
 
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/ioctl.h>
#include <sys/file.h>
#include <fcntl.h>
#include <termios.h>
#include <unistd.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <signal.h>
#include <pwd.h>
#include <errno.h>
 
#include <tqglobal.h>
 
#include <tdelocale.h>
#include <kdebug.h>
 
#include "modem.h"
 
 
#ifndef CSOH
#define CSOH  01
#endif
 
#ifndef CSTX
#define CSTX  02
#endif
 
#ifndef CEOT
#define CEOT  04
#endif
 
#ifndef CACK
#define CACK  06
#endif
 
#ifndef CNAK
#define CNAK 025
#endif
 
#ifndef CCAN
#define CCAN 030
#endif
 
 
 
Modem::Modem( KandyPrefs *kprefs, TQObject *parent, const char *name ) :
  TQObject(parent, name), fd(-1)
{
  mOpen = false;
 
  prefs = kprefs;
 
  timer = new TQTimer( this, "modemtimer" );
  TQ_CHECK_PTR( timer );
  connect( timer, TQ_SIGNAL( timeout() ), TQ_SLOT( timerDone() ) );
 
  init();
  xreset();
}
 
 
Modem::~Modem()
{
  close();
}
 
 
void Modem::setSpeed( int speed )
{
  switch ( speed ) {
    case 300:
      cspeed = B300;
      break;
    case 600:
      cspeed = B600;
      break;
    case 1200:
      cspeed = B1200;
      break;
    case 2400:
      cspeed = B2400;
      break;
    case 4800:
      cspeed = B4800;
      break;
    case 9600:
      cspeed = B9600;
      break;
    case 19200:
      cspeed = B19200;
      break;
    case 38400:
      cspeed = B38400;
      break;
    case 57600:
      cspeed = B57600;
      break;
    case 115200:
      cspeed = B115200;
      break;
    case 230400:
      cspeed = B230400;
      break;
    default:
#ifdef MODEM_DEBUG
      fprintf(stderr, "Modem: setSpeed(): fallback to default speed.\n");
#endif
      cspeed = B38400;
  }
}
 
 
void Modem::setData( int data )
{
  cflag &= ~CSIZE;
 
  switch ( data ) {
    case 5:
      cflag |= CS5;
      break;
    case 6:
      cflag |= CS6;
      break;
    case 7:
      cflag |= CS7;
      break;
    default:
      cflag |= CS8;
  }
}
 
 
void Modem::setParity( char parity )
{
  cflag &= ~( PARENB | PARODD );
 
  if ( parity == 'E' )
    cflag |= PARENB;
  else if ( parity == 'O' )
    cflag |= PARENB | PARODD;
}
 
 
void Modem::setStop( int stop )
{
  if (stop == 2)
    cflag |= CSTOPB;
  else
    cflag &= ~CSTOPB;
}
 
 
bool Modem::open()
{
  struct termios tty;
 
  close();
 
    if (fd == -1)
    {
        TQCString dev = TQFile::encodeName( (*prefs).serialDevice() );
        const char *fdev = dev.data();
        if ( ( fd = ::open( fdev, O_RDWR | O_NOCTTY | O_NONBLOCK ) ) == -1 ) {
            emit errorMessage( i18n( "Unable to open device '%1'. "
                                                            "Please check that you have sufficient permissions." )
                                                            .arg( fdev ) );
            return false;
        }
    }
 
  if ( !lockDevice() )
    return false;
 
  tcflush( fd, TCIOFLUSH );
  if ( tcgetattr( fd, &init_tty ) == -1 ) {
    int errnumber = errno;
    emit errorMessage( i18n( "Communication setup failed (tcgetattr code: %1)" )
        .arg(strerror(errnumber)) );
        unlockDevice();
    ::close( fd );
    fd = -1;
    return false;
  }
 
  memset( &tty, 0, sizeof( tty ) );
  tty.c_iflag = IGNBRK | IGNPAR;
  tty.c_oflag = 0;
  tty.c_cflag = cflag;
  tty.c_lflag = 0;
  cfsetospeed( &tty, cspeed );
  cfsetispeed( &tty, cspeed );
  tcdrain( fd );
 
  if ( tcsetattr( fd, TCSANOW, &tty ) == -1 ) {
    emit errorMessage( i18n( "tcsetattr() failed." ) );
        unlockDevice();
    ::close( fd );
    fd = -1;
    return false;
  }
 
  sn = new TQSocketNotifier( fd, TQSocketNotifier::Read, this,
                            "modemsocketnotifier" );
  TQ_CHECK_PTR( sn );
  connect( sn, TQ_SIGNAL( activated( int ) ), TQ_SLOT( readChar( int ) ) );
 
  mOpen = true;
 
  return true;
}
 
 
void Modem::close()
{
  timer->stop();
 
  delete sn;
  sn = 0;
 
  unlockDevice();
 
  if ( fd ) {
    tcflush( fd, TCIOFLUSH );
    tcsetattr( fd, TCSANOW, &init_tty );
    ::close( fd );
    fd = -1;
  }
 
  xreset();
 
  mOpen = false;
}
 
 
void Modem::flush()
{
  if ( fd != -1) {
    tcflush( fd, TCIOFLUSH );
    bufpos = 0;
  }
}
 
bool Modem::lockDevice()
{
  if (is_locked)
    return true;
 
    if (flock(fd, LOCK_EX))
    {
      // Locking failed
    is_locked = false;
    emit errorMessage(i18n("Unable to lock device '%1'.").arg((*prefs).serialDevice()));
    }
    else
    {
    is_locked = true;
  }
 
    return is_locked;
}
 
 
void Modem::unlockDevice()
{
  if (fd != -1 && is_locked)
  {
        flock(fd, LOCK_UN);
        is_locked = false;
    }
}
 
 
bool Modem::dsrOn()
{
  int flags;
 
 
  if ( fd == -1 ) {
#ifdef MODEM_DEBUG
    fprintf( stderr, "Modem: dsrOn(): File not open.\n" );
#endif
    return false;
  }
 
  if ( ioctl( fd, TIOCMGET, &flags ) == -1 ) {
#ifdef MODEM_DEBUG
    fprintf( stderr, "Modem: dsrOn(): ioctl() failed.\n" );
#endif
    return false;
  }
 
  return ( flags & TIOCM_DSR ) != 0;
}
 
 
bool Modem::ctsOn()
{
  int flags;
 
 
  if ( fd == -1 ) {
#ifdef MODEM_DEBUG
    fprintf( stderr, "Modem: ctsOn(): File not open.\n" );
#endif
    return false;
  }
 
  if ( ioctl( fd, TIOCMGET, &flags ) == -1) {
#ifdef MODEM_DEBUG
    fprintf( stderr, "Modem: ctsOn(): ioctl() failed.\n" );
#endif
    return false;
  }
 
  return ( flags & TIOCM_CTS ) != 0;
}
 
 
void Modem::writeChar( const char c )
{
  write( fd, (const void *) &c, 1 );
}
 
 
void Modem::writeLine( const char *line )
{
  kdDebug() << "Modem::writeLine(): " << line << endl;
 
  write( fd, (const void *) line, strlen( line ) );
  writeChar( '\r' );
}
 
 
void Modem::timerStart( int msec )
{
  timer->start( msec, true );
}
 
 
void Modem::receiveXModem( bool crc )
{
  disconnect( sn, 0, this, 0 );
  connect( sn, TQ_SIGNAL( activated( int ) ), TQ_SLOT( readXChar( int ) ) );
 
  xcrc = crc;
 
  if ( xcrc ) {
    writeChar( 'C' );
    xstate = 1;
    timerStart( 3000 );
  } else {
    writeChar( CNAK );
    xstate = 5;
    timerStart( 10000 );
  }
 
  xblock = 1;
}
 
 
void Modem::abortXModem()
{
  timer->stop();
  writeChar( CCAN );
  xreset();
  emit xmodemDone( false );
}
 
 
void Modem::timerDone()
{
#ifdef MODEM_DEBUG
  fprintf( stderr, "Modem: timeout, xstate = %d.\n", xstate );
#endif
 
  switch ( xstate ) {
    case  0:            /* non-XModem mode  */
      emit timeout();
      break;
 
    case  1:            /* 1st 'C' sent     */
    case  2:            /* 2nd 'C' sent     */
    case  3:            /* 3rd 'C' sent     */
      writeChar( 'C' );
      xstate++;
      timerStart( 1000 );   /* Should be 3000 in original XModem    */
      break;
 
    case  4:            /* 4th 'C' sent     */
      xcrc = false;
 
    case  5:            /* 1st <NAK> sent   */
    case  6:            /* 2nd <NAK> sent   */
    case  7:            /* 3rd <NAK> sent   */
    case  8:            /* 4th <NAK> sent   */
    case  9:            /* 5th <NAK> sent   */
      writeChar( CNAK );
      xstate++;
      timerStart( 1000 );   /* Should be 10000 in original XModem   */
      break;
 
    case 10:            /* 6th <NAK> sent   */
      xreset();
      emit xmodemDone( false );
      break;
 
    default:            /* pending XModem block */
      writeChar( CNAK );
      xstate = 5;
      timerStart( 1000 );   /* Should be 10000 in original XModem   */
    }
}
 
 
void Modem::readChar( int )
{
  uchar c;
 
 
  while ( read( fd, (void *) &c, 1 ) == 1 ) {
    if ( c == '\n' ) {
      buffer[ bufpos ] = 0;
      bufpos = 0;
      emit gotLine( (const char *) buffer );
      break;
    } else
    if ( ( bufpos < 1000 ) && ( c != '\r' ) )
      buffer[ bufpos++ ] = c;
  }
}
 
 
void Modem::readXChar( int )
{
  uchar c;
  static uchar crc_hi, block, cblock;
 
 
  while ( read( fd, (void *) &c, 1 ) == 1 ) {
    switch ( xstate ) {
      case  1:  /* 1st 'C' sent     */
      case  2:  /* 2nd 'C' sent     */
      case  3:  /* 3rd 'C' sent     */
      case  4:  /* 4th 'C' sent     */
      case  5:  /* 1st <NAK> sent   */
      case  6:  /* 2nd <NAK> sent   */
      case  7:  /* 3rd <NAK> sent   */
      case  8:  /* 4th <NAK> sent   */
      case  9:  /* 5th <NAK> sent   */
      case 10:  /* 6th <NAK> sent   */
    if ( c == CSOH ) {
      timerStart( 1000 );
      xsize = 128;
      xstate = 11;
    } else
    if ( c == CSTX ) {
      timerStart( 1000 );
      xsize = 1024;
      xstate = 11;
        } else
    if ( c == CEOT ) {
      timer->stop();
      writeChar( CACK );
      xreset();
      emit xmodemDone( true );
    } else
      timerStart( 1000 );
    break;
 
      case 11:  /* <SOH> or <STX> received   */
    timerStart( 1000 );
    block = c;
    xstate++;
    break;
 
      case 12:  /* block number received    */
    timerStart( 1000 );
    cblock = c;
    xstate++;
    bufpos = 0;
    break;
 
      case 13:  /* complement block number received */
    timerStart( 1000 );
    buffer[ bufpos++ ] = c;
    if ( bufpos == xsize ) {
      bufpos = 0;
      xstate++;
      if ( !xcrc )
        xstate++;
    }
    break;
 
      case 14:  /* data block received  */
    timerStart( 1000 );
    crc_hi = c;
    xstate++;
    break;
 
      case 15:  /* crc high-byte received   */
    timerStart( 10000 );
    xstate = 4;
    if ( (uchar) ( block ^ cblock ) != 0xff ) {
      writeChar( CNAK );
      break;
    }
    if ( block+1 == xblock ) {
      writeChar( CACK );
      break;
    }
    if ( block != xblock ) {
      timer->stop();
      writeChar( CCAN );
      xreset();
      emit xmodemDone( false );
      break;
    }
    if ( xcrc ) {
      if ( ( (ushort) crc_hi << 8 | (ushort) c ) != calcCRC() ) {
        writeChar( CNAK );
        break;
      }
    } else {
      if ( c != calcChecksum() ) {
        writeChar( CNAK );
        break;
      }
    }
    writeChar( CACK );
    xblock++;
    emit gotXBlock( buffer, xsize );
    break;
 
      default:
    break;
    }
  }
}
 
 
void Modem::init()
{
  is_locked = false;
 
  fd = -1;
  sn = 0;
 
  cspeed = B38400;
 
  // No flow control
  cflag = CS8 | CREAD | CLOCAL;
  // cflag = CS8 | CREAD | CLOCAL | CRTSCTS;
 
  bufpos = 0;
}
 
 
void Modem::xreset()
{
  bufpos = 0;
 
  xstate = 0;
  xcrc = false;
  xblock = 0;
  xsize = 0;
 
  if ( sn ) {
    disconnect( sn, 0, this, 0 );
    connect( sn, TQ_SIGNAL( activated( int ) ), TQ_SLOT( readChar( int ) ) );
  }
}
 
 
uchar Modem::calcChecksum()
{
  int i;
  uchar c = 0;
 
 
  for ( i = 0; i < xsize; i++ )
    c += buffer[ i ];
 
  return c;
}
 
 
ushort Modem::calcCRC()
{
  int i, j;
  ushort c = 0;
 
 
  for ( i = 0; i < xsize; i++ ) {
    c ^= (ushort) buffer[ i ] << 8;
    for ( j = 0; j < 8; j++ )
      if ( c & 0x8000 )
        c = c << 1 ^ 0x1021;
      else
    c <<= 1;
  }
 
  return c;
}
 
#include "modem.moc"