/* * bim.{cc,hh} -- element reads and writes packets to/from * ABACOM BIM-4xx-RS232 radios * Robert Morris * * Copyright (c) 1999-2000 Massachusetts Institute of Technology * * Permission is hereby granted, free of charge, to any person obtaining a * copy of this software and associated documentation files (the "Software"), * to deal in the Software without restriction, subject to the conditions * listed in the Click LICENSE file. These conditions include: you must * preserve this copyright notice, and you cannot mention the copyright * holders in advertising related to the Software without their permission. * The Software is provided WITHOUT ANY WARRANTY, EXPRESS OR IMPLIED. This * notice is a summary of the Click LICENSE file; the license in that file is * legally binding. */#include <click/config.h>#include "bim.hh"#include <click/error.hh>#include <click/packet.hh>#include <click/confparse.hh>#include <click/glue.hh>#include "bim-proto.hh"#include <click/standard/scheduleinfo.hh>#include <unistd.h>#include <termios.h>#include <fcntl.h>#include <sys/ioctl.h>CLICK_DECLSBIM::BIM()  : _task(this){  _speed = 9600;  _fd = -1;  _len = _started = _escaped = 0;}BIM::~BIM(){  if(_fd >= 0)    close(_fd);}intBIM::configure(Vector<String> &conf, ErrorHandler *errh){  if (cp_va_kparse(conf, this, errh,		   "DEVNAME", cpkP+cpkM, cpString, &_dev,		   "BAUD", cpkP, cpInteger, &_speed,		   cpEnd) < 0)    return -1;  if(_speed == 4800)    _speed = B4800;  else if(_speed == 9600)    _speed = B9600;  else if(_speed == 19200)    _speed = B19200;  else if(_speed == 38400)    _speed = B38400;  else {    return errh->error("bad speed %d", _speed);  }  return 0;}intBIM::initialize(ErrorHandler *errh){  if (_fd >= 0)    return 0;  else if (!_dev)    return errh->error("device name not set");  char *dname = _dev.mutable_c_str();  _fd = open(dname, O_RDWR|O_NONBLOCK, 0);  if(_fd < 0)    return errh->error("%s: %s", dname, strerror(errno));  ioctl(_fd, TIOCEXCL, 0);  struct termios t;  if(tcgetattr(_fd, &t) < 0)    return errh->error("bad tcgetattr");  t.c_iflag = IGNBRK;  t.c_oflag = 0;  t.c_cflag = CS8|CREAD|HUPCL|CLOCAL;  t.c_lflag = 0;  cfsetispeed(&t, _speed);  cfsetospeed(&t, _speed);  if(tcsetattr(_fd, TCSANOW, &t) < 0)    return errh->error("can't set terminal characteristics");#ifdef FIONBIO  int yes = 1;  if(ioctl(_fd, FIONBIO, &yes) < 0)    return errh->error("can't set non-blocking IO");#else  return errh->error("not configured for non-blocking IO");#endif#ifdef TCIOFLUSH  tcflush(_fd, TCIOFLUSH);#elif defined(TIOCFLUSH)  tcflush(_fd, TIOCFLUSH);#else  return errh->error("this architecture has no TIOCFLUSH");#endif  ScheduleInfo::join_scheduler(this, &_task, errh);  add_select(_fd, SELECT_READ | SELECT_WRITE);  return 0;}voidBIM::selected(int fd){  int cc, i;  char b[128];  if (fd != _fd)    return;  cc = read(_fd, b, sizeof(b));  for(i = 0; i < cc; i++)    got_char(b[i] & 0xff);}voidBIM::got_char(int c){  if(_started == 0 && _escaped == 0 && c == BIM_ESC){    _escaped = 1;  } else if(_escaped && c == BIM_ESC_START){    _escaped = 0;    _started = 1;    _len = 0;  } else if(_started && !_escaped && c == BIM_ESC){    _escaped = 1;  } else if(_started && _escaped && c == BIM_ESC_END){    Packet *p = Packet::make(_buf, _len);    output(0).push(p);    _escaped = _started = _len = 0;  } else if(_started && _escaped && c == BIM_ESC_ESC){    _buf[_len++] = BIM_ESC;    _escaped = 0;  } else if(_started && !_escaped && c != BIM_ESC){    _buf[_len++] = c;  } else if(_started || _escaped){    fprintf(stderr, "bim: framing error, st %d es %d _len %d c %02x\n",            _started, _escaped, _len, c);    _started = _escaped = _len = 0;  }  if(_len > 1024){    fprintf(stderr, "bim: incoming packet too large\n");    _len = _started = 0;  }}boolBIM::run_task(Task *){  Packet *p = input(0).pull();  if (p)    push(0, p);  _task.fast_reschedule();  return p != 0;}voidBIM::push(int, Packet *p){  send_packet(p->data(), p->length());  p->kill();}voidBIM::send_packet(const unsigned char buf[], unsigned int len){  unsigned int i, j;  char big[2048];  if(len > 1024){    fprintf(stderr, "bim: packet too large\n");    return;  }  j = 0;  for(i = 0; i < 13; i++){    big[j++] = 'U'; /* preamble 01010101 */  }  big[j++] = 0xff; /* sync */  big[j++] = BIM_ESC;  big[j++] = BIM_ESC_START;  for(i = 0; i < len; i++){    int c = buf[i] & 0xff;    if(c == BIM_ESC){      big[j++] = BIM_ESC;      big[j++] = BIM_ESC_ESC;    } else {      big[j++] = c;    }  }  big[j++] = BIM_ESC;  big[j++] = BIM_ESC_END;  if(write(_fd, big, j) != (int) j){    perror("bim: write rs232");  }#if 0  {    FILE *fp = fopen("foo", "a");    if(fp){      double a = 0.5;      int by, bi;      for(by = 0; by < j; by++){        for(bi = 0; bi < 8; bi++){          int bit = (big[by] >> bi) & 1;          a = (a * 0.9) + (bit * 0.1);          fprintf(fp, "%.5f\n", a);        }      }      fprintf(fp, "\n");      fclose(fp);    }  }#endif}CLICK_ENDDECLSEXPORT_ELEMENT(BIM)ELEMENT_REQUIRES(userlevel)