/*
  //  PLP - An implementation of the PSION link protocol
  //
  //
  //  The code in this file was written by Rudolf Koenig
  //  (rfkoenig@immd4.informatik.uni-erlangen.de). (from his p3nfs code)
  //  The Copyright remains his
  //  
  //
  //  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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  //
  //  e-mail philip.proudman@btinternet.com
  */


#include <stdio.h>
#include <fcntl.h>
#include <unistd.h>	/* for usleep() */
#include <string.h>	/* for bzero() */
#include <termios.h>
#if defined(linux) || defined(_IBMR2) || defined(__NetBSD__)
# include <sys/ioctl.h>	/* for ioctl() */
#endif
#include <sys/errno.h>
#ifdef sun
# include <sys/ttold.h>	/* sun has TIOCEXCL there */
#endif
#if defined (__SVR4)
#include <stdlib.h>
#endif

static struct termios sti;

#ifndef hpux
# define mflag int
#else /* hpux */
# include <sys/termiox.h>
# include <sys/modem.h>
#endif


/*
#if !defined(CRTSCTS) && defined(_IBMR2)
#define CRTSCTS 0x80000000
#endif
*/

#ifdef __sgi
#define CRTSCTS CNEW_RTSCTS
#endif

#ifndef O_NOCTTY
# define O_NOCTTY 0
#endif

int init_serial(const char *dev, int speed, int debug, int background)
{
  int fd, baud, clocal;
  struct termios ti;
#ifdef hpux
  struct termiox tx;
#endif
  static struct baudRate { int speed, baud; } btable[] =
    {
      { 9600,	B9600},

#ifdef B19200
      { 19200,	B19200},
#else
# ifdef EXTA
      { 19200,	EXTA},
# endif
#endif

#ifdef B38400
      { 38400,	B38400},
#else
# ifdef EXTB
      { 38400,	EXTB},
# endif
#endif

# ifdef B57600
      { 57600,	B57600},
# endif
# ifdef B115200
      { 115200,	B115200},
# endif
      { 4800,	B4800},
      { 2400,	B2400},
      { 1200,	B1200},
      { 300, 	B300},
      { 75,	B75},
      { 50,	B50},
      {0,0}
    }, *bptr;
  
  if(speed)
    {
      for (bptr = btable; bptr->speed; bptr++)
	if (bptr->speed == speed)
	  break;
      if (!bptr->baud)
	{
	  fprintf(stderr, "Cannot match selected speed %d\n", speed);
	  exit(1);
	}
      baud = bptr->baud;
    }
  else
    {
      baud = 0;
    }

  if(background)
    {
      int uid, euid;

      if(debug) printf("using %s...\n", dev);
      euid = geteuid();
      uid = getuid();

#ifdef hpux
#define seteuid(a) setresuid(-1, a, -1)
#endif

      clocal = CLOCAL;
      if (seteuid(uid))
	{
	  perror("seteuid"); exit(1);
	}
      if((fd = open(dev, O_RDWR | O_NDELAY | O_NOCTTY , 0)) < 0)
	{
	  perror(dev); exit(1);
	}
      if (seteuid(euid))
	{
	  perror("seteuid back"); exit(1);
	}

      if(debug) printf("open done\n");
#ifdef TIOCEXCL
      ioctl(fd, TIOCEXCL, (char *) 0);	/* additional open() calls shall fail */
#else
      fprintf(stderr, "WARNING: opened %s non-exclusive!\n", dev);
#endif
    }
  else
    {
      char *f;

      fd = dup(0);

      if(tcgetattr(fd, &ti) < 0)
        {
	  perror("tcgetattr serial");
	  exit(1);
	}
      sti = ti ;      /* Save the state for shutdown time */
      clocal = ti.c_cflag & CLOCAL ;  /* and for setup */

      close(0);				/* Let's close 0,1,2 */
      f = "/dev/null";
      if(open(f, O_RDONLY, 0) != 0)
        {
	  perror(f); exit(0);
	}
      close(1);
      f = "/tmp/p3nfsd.out";
      if(open(f, O_WRONLY|O_CREAT|O_APPEND, 0666) != 1)
        {
	  perror(f); exit(0);
	}
      fprintf(stderr, "p3nfsd: output written to %s\n", f);
      close(2);
      dup(1);
    }
  
  memset(&ti, 0, sizeof(struct termios));
#if defined(hpux) || defined(_IBMR2)
  ti.c_cflag = CS8 | HUPCL | clocal | CREAD;
#endif
#if defined(sun) || defined(linux) || defined(__sgi) || defined(__NetBSD__) || defined(__FreeBSD__)
  ti.c_cflag = CS8 | HUPCL | clocal | CRTSCTS | CREAD;
  ti.c_iflag = IGNBRK | IGNPAR;
  ti.c_cc[VMIN] = 1;
  ti.c_cc[VTIME] = 0;
#endif
  cfsetispeed(&ti, baud);
  cfsetospeed(&ti, baud);

  if(tcsetattr(fd, TCSADRAIN, &ti) < 0)
    perror("tcsetattr TCSADRAIN");

#ifdef hpux
  bzero(&tx, sizeof(struct termiox));
  tx.x_hflag = RTSXOFF | CTSXON;
  if (ioctl(fd, TCSETXW, &tx) < 0)
    perror("TCSETXW");
#endif

#if defined(_IBMR2)
  ioctl(fd, TXDELCD, "dtr");
  ioctl(fd, TXDELCD, "xon");
  ioctl(fd, TXADDCD, "rts");  /* That's how AIX does CRTSCTS */
#endif

  return fd;
}

void ser_exit(int fd)
{
  struct termios ti;
  if(tcgetattr(fd, &ti) < 0) {
    perror("TCGETSW");
  }
  ti.c_cflag &= ~CRTSCTS;
  if(tcsetattr(fd, TCSANOW, &ti) < 0) {
    perror("TCSETSW");
  }
  (void) close(fd);
}