/* Serial interface for local (hardwired) serial ports on Un*x like systems
   Copyright 1992, 1993 Free Software Foundation, Inc.

This file is part of GDB.

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., 675 Mass Ave, Cambridge, MA 02139, USA.  */

#include "defs.h"
#include "serial.h"
#include <fcntl.h>
#include <sys/types.h>

#if !defined (HAVE_TERMIOS) && !defined (HAVE_TERMIO) && !defined (HAVE_SGTTY)
#define HAVE_SGTTY
#endif

#ifdef HAVE_TERMIOS
#include <termios.h>
#include <unistd.h>

struct hardwire_ttystate
{
  struct termios termios;
  pid_t process_group;
};
#endif

#ifdef HAVE_TERMIO
#include <termio.h>

struct hardwire_ttystate
{
  struct termio termio;
  int process_group;
};
#endif

#ifdef HAVE_SGTTY
/* Needed for the code which uses select().  We would include <sys/select.h>
   too if it existed on all systems.  */
#include <sys/time.h>

#include <sgtty.h>

struct hardwire_ttystate
{
  struct sgttyb sgttyb;
  struct tchars tc;
  struct ltchars ltc;
  /* Line discipline flags.  */
  int lmode;

#ifdef SHORT_PGRP
  /* This is only used for the ultra.  Does it have pid_t?  */
  short process_group;
#else
  int process_group;
#endif
};
#endif

static int hardwire_open PARAMS ((serial_t scb, const char *name));
static void hardwire_raw PARAMS ((serial_t scb));
static int wait_for PARAMS ((serial_t scb, int timeout));
static int hardwire_readchar PARAMS ((serial_t scb, int timeout));
static int rate_to_code PARAMS ((int rate));
static int hardwire_setbaudrate PARAMS ((serial_t scb, int rate));
static int hardwire_write PARAMS ((serial_t scb, const char *str, int len));
static void hardwire_restore PARAMS ((serial_t scb));
static void hardwire_close PARAMS ((serial_t scb));
static int get_tty_state PARAMS ((serial_t scb, struct hardwire_ttystate *state));
static int set_tty_state PARAMS ((serial_t scb, struct hardwire_ttystate *state));
static serial_ttystate hardwire_get_tty_state PARAMS ((serial_t scb));
static int hardwire_set_tty_state PARAMS ((serial_t scb, serial_ttystate state));

/* Open up a real live device for serial I/O */

static int
hardwire_open(scb, name)
     serial_t scb;
     const char *name;
{
  scb->fd = open (name, O_RDWR);
  if (scb->fd < 0)
    return -1;

  return 0;
}

static int
get_tty_state(scb, state)
     serial_t scb;
     struct hardwire_ttystate *state;
{
#ifdef HAVE_TERMIOS
  pid_t new_process_group;

  if (tcgetattr(scb->fd, &state->termios) < 0)
    return -1;

  if (!job_control)
    return 0;

  new_process_group = tcgetpgrp (scb->fd);
  if (new_process_group == (pid_t)-1)
    return -1;
  state->process_group = new_process_group;
  return 0;
#endif

#ifdef HAVE_TERMIO
  if (ioctl (scb->fd, TCGETA, &state->termio) < 0)
    return -1;

  if (!job_control)
    return 0;

  return ioctl (scb->fd, TIOCGPGRP, &state->process_group);
#endif

#ifdef HAVE_SGTTY
  if (ioctl (scb->fd, TIOCGETP, &state->sgttyb) < 0)
    return -1;
  if (ioctl (scb->fd, TIOCGETC, &state->tc) < 0)
    return -1;
  if (ioctl (scb->fd, TIOCGLTC, &state->ltc) < 0)
    return -1;
  if (ioctl (scb->fd, TIOCLGET, &state->lmode) < 0)
    return -1;

  if (!job_control)
    return 0;

  return ioctl (scb->fd, TIOCGPGRP, &state->process_group);
#endif
}

static int
set_tty_state(scb, state)
     serial_t scb;
     struct hardwire_ttystate *state;
{
#ifdef HAVE_TERMIOS
  if (tcsetattr(scb->fd, TCSANOW, &state->termios) < 0)
    return -1;

  if (!job_control)
    return 0;

  /* Need to ignore errors, at least if attach_flag is set.  */
  tcsetpgrp (scb->fd, state->process_group);
  return 0;
#endif

#ifdef HAVE_TERMIO
  if (ioctl (scb->fd, TCSETA, &state->termio) < 0)
    return -1;

  if (!job_control)
    return 0;

  /* Need to ignore errors, at least if attach_flag is set.  */
  ioctl (scb->fd, TIOCSPGRP, &state->process_group);
  return 0;
#endif

#ifdef HAVE_SGTTY
  if (ioctl (scb->fd, TIOCSETN, &state->sgttyb) < 0)
    return -1;

  if (!job_control)
    return 0;

  /* Need to ignore errors, at least if attach_flag is set.  */
  ioctl (scb->fd, TIOCSPGRP, &state->process_group);
  return 0;
#endif
}

static serial_ttystate
hardwire_get_tty_state(scb)
     serial_t scb;
{
  struct hardwire_ttystate *state;

  state = (struct hardwire_ttystate *)xmalloc(sizeof *state);

  if (get_tty_state(scb, state))
    return NULL;

  return (serial_ttystate)state;
}

static int
hardwire_set_tty_state(scb, ttystate)
     serial_t scb;
     serial_ttystate ttystate;
{
  struct hardwire_ttystate *state;

  state = (struct hardwire_ttystate *)ttystate;

  return set_tty_state(scb, state);
}

static int
hardwire_noflush_set_tty_state (scb, new_ttystate, old_ttystate)
     serial_t scb;
     serial_ttystate new_ttystate;
     serial_ttystate old_ttystate;
{
  struct hardwire_ttystate new_state;
  struct hardwire_ttystate *state = (struct hardwire_ttystate *) old_ttystate;

  new_state = *(struct hardwire_ttystate *)new_ttystate;

#ifdef HAVE_TERMIOS
  /* I'm not sure whether this is necessary; the manpage makes no mention
     of discarding input when switching to/from ICANON.  */
  if (state->termios.c_lflag & ICANON)
    new_state.termios.c_lflag |= ICANON;
  else
    new_state.termios.c_lflag &= ~ICANON;
#endif

#ifdef HAVE_TERMIO
  /* I'm not sure whether this is necessary; the manpage makes no mention
     of discarding input when switching to/from ICANON.  */
  if (state->termio.c_lflag & ICANON)
    new_state.termio.c_lflag |= ICANON;
  else
    new_state.termio.c_lflag &= ~ICANON;
#endif

#ifdef HAVE_SGTTY
  if (state->sgttyb.sg_flags & RAW)
    new_state.sgttyb.sg_flags |= RAW;
  else
    new_state.sgttyb.sg_flags &= ~RAW;

  /* I'm not sure whether this is necessary; the manpage just mentions
     RAW not CBREAK.  */
  if (state->sgttyb.sg_flags & CBREAK)
    new_state.sgttyb.sg_flags |= CBREAK;
  else
    new_state.sgttyb.sg_flags &= ~CBREAK;
#endif

  return set_tty_state (scb, &new_state);
}

static void
hardwire_print_tty_state (scb, ttystate)
     serial_t scb;
     serial_ttystate ttystate;
{
  struct hardwire_ttystate *state = (struct hardwire_ttystate *) ttystate;
  int i;

  printf_filtered ("Process group = %d\n", state->process_group);

#ifdef HAVE_TERMIOS
  printf_filtered ("c_iflag = 0x%x, c_oflag = 0x%x,\n",
		   state->termios.c_iflag, state->termios.c_oflag);
  printf_filtered ("c_cflag = 0x%x, c_lflag = 0x%x\n",
		   state->termios.c_cflag, state->termios.c_lflag);
#if 0
  /* This not in POSIX, and is not really documented by those systems
     which have it (at least not Sun).  */
  printf_filtered ("c_line = 0x%x.\n", state->termios.c_line);
#endif
  printf_filtered ("c_cc: ");
  for (i = 0; i < NCCS; i += 1)
    printf_filtered ("0x%x ", state->termios.c_cc[i]);
  printf_filtered ("\n");
#endif

#ifdef HAVE_TERMIO
  printf_filtered ("c_iflag = 0x%x, c_oflag = 0x%x,\n",
		   state->termio.c_iflag, state->termio.c_oflag);
  printf_filtered ("c_cflag = 0x%x, c_lflag = 0x%x, c_line = 0x%x.\n",
		   state->termio.c_cflag, state->termio.c_lflag,
		   state->termio.c_line);
  printf_filtered ("c_cc: ");
  for (i = 0; i < NCC; i += 1)
    printf_filtered ("0x%x ", state->termio.c_cc[i]);
  printf_filtered ("\n");
#endif

#ifdef HAVE_SGTTY
  printf_filtered ("sgttyb.sg_flags = 0x%x.\n", state->sgttyb.sg_flags);

  printf_filtered ("tchars: ");
  for (i = 0; i < (int)sizeof (struct tchars); i++)
    printf_filtered ("0x%x ", ((unsigned char *)&state->tc)[i]);
  printf_filtered ("\n");

  printf_filtered ("ltchars: ");
  for (i = 0; i < (int)sizeof (struct ltchars); i++)
    printf_filtered ("0x%x ", ((unsigned char *)&state->ltc)[i]);
  printf_filtered ("\n");

  printf_filtered ("lmode:  0x%x\n", state->lmode);
#endif
}

static int
hardwire_flush_output (scb)
     serial_t scb;
{
#ifdef HAVE_TERMIOS
  return tcflush (scb->fd, TCOFLUSH);
#endif

#ifdef HAVE_TERMIO
  return ioctl (scb->fd, TCFLSH, 1);
#endif

#ifdef HAVE_SGTTY
  /* This flushes both input and output, but we can't do better.  */
  return ioctl (scb->fd, TIOCFLUSH, 0);
#endif  
}

static void
hardwire_raw(scb)
     serial_t scb;
{
  struct hardwire_ttystate state;

  if (get_tty_state(scb, &state))
    fprintf(stderr, "get_tty_state failed: %s\n", safe_strerror(errno));

#ifdef HAVE_TERMIOS
  state.termios.c_iflag = 0;
  state.termios.c_oflag = 0;
  state.termios.c_lflag = 0;
  state.termios.c_cflag &= ~(CSIZE|PARENB);
  state.termios.c_cflag |= CS8;
  state.termios.c_cc[VMIN] = 0;
  state.termios.c_cc[VTIME] = 0;
#endif

#ifdef HAVE_TERMIO
  state.termio.c_iflag = 0;
  state.termio.c_oflag = 0;
  state.termio.c_lflag = 0;
  state.termio.c_cflag &= ~(CSIZE|PARENB);
  state.termio.c_cflag |= CS8;
  state.termio.c_cc[VMIN] = 0;
  state.termio.c_cc[VTIME] = 0;
#endif

#ifdef HAVE_SGTTY
  state.sgttyb.sg_flags |= RAW | ANYP;
  state.sgttyb.sg_flags &= ~(CBREAK | ECHO);
#endif

  scb->current_timeout = 0;

  if (set_tty_state (scb, &state))
    fprintf(stderr, "set_tty_state failed: %s\n", safe_strerror(errno));
}

/* Wait for input on scb, with timeout seconds.  Returns 0 on success,
   otherwise SERIAL_TIMEOUT or SERIAL_ERROR.

   For termio{s}, we actually just setup VTIME if necessary, and let the
   timeout occur in the read() in hardwire_read().
 */

static int
wait_for(scb, timeout)
     serial_t scb;
     int timeout;
{
  int numfds;

#ifdef HAVE_SGTTY
  struct timeval tv;
  fd_set readfds;

  FD_ZERO (&readfds);

  tv.tv_sec = timeout;
  tv.tv_usec = 0;

  FD_SET(scb->fd, &readfds);

  while (1)
    {
      if (timeout >= 0)
	numfds = select(scb->fd+1, &readfds, 0, 0, &tv);
      else
	numfds = select(scb->fd+1, &readfds, 0, 0, 0);

      if (numfds <= 0)
	if (numfds == 0)
	  return SERIAL_TIMEOUT;
	else if (errno == EINTR)
	  continue;
	else
	  return SERIAL_ERROR;	/* Got an error from select or poll */

      return 0;
    }

#endif	/* HAVE_SGTTY */

#if defined HAVE_TERMIO || defined HAVE_TERMIOS
  if (timeout == scb->current_timeout)
    return 0;

  {
    struct hardwire_ttystate state;

    if (get_tty_state(scb, &state))
      fprintf(stderr, "get_tty_state failed: %s\n", safe_strerror(errno));

#ifdef HAVE_TERMIOS
    state.termios.c_cc[VTIME] = timeout * 10;
#endif

#ifdef HAVE_TERMIO
    state.termio.c_cc[VTIME] = timeout * 10;
#endif

    scb->current_timeout = timeout;

    if (set_tty_state (scb, &state))
      fprintf(stderr, "set_tty_state failed: %s\n", safe_strerror(errno));

    return 0;
  }
#endif	/* HAVE_TERMIO || HAVE_TERMIOS */
}

/* Read a character with user-specified timeout.  TIMEOUT is number of seconds
   to wait, or -1 to wait forever.  Use timeout of 0 to effect a poll.  Returns
   char if successful.  Returns -2 if timeout expired, EOF if line dropped
   dead, or -3 for any other error (see errno in that case). */

static int
hardwire_readchar(scb, timeout)
     serial_t scb;
     int timeout;
{
  int status;

  if (scb->bufcnt-- > 0)
    return *scb->bufp++;

  status = wait_for(scb, timeout);

  if (status < 0)
    return status;

  scb->bufcnt = read(scb->fd, scb->buf, BUFSIZ);

  if (scb->bufcnt <= 0)
    if (scb->bufcnt == 0)
      return SERIAL_TIMEOUT;	/* 0 chars means timeout [may need to
				   distinguish between EOF & timeouts
				   someday] */
    else
      return SERIAL_ERROR;	/* Got an error from read */

  scb->bufcnt--;
  scb->bufp = scb->buf;
  return *scb->bufp++;
}

#ifndef B19200
#define B19200 EXTA
#endif

#ifndef B38400
#define B38400 EXTB
#endif

/* Translate baud rates from integers to damn B_codes.  Unix should
   have outgrown this crap years ago, but even POSIX wouldn't buck it.  */

static struct
{
  int rate;
  int code;
}
baudtab[] =
{
  {50, B50},
  {75, B75},
  {110, B110},
  {134, B134},
  {150, B150},
  {200, B200},
  {300, B300},
  {600, B600},
  {1200, B1200},
  {1800, B1800},
  {2400, B2400},
  {4800, B4800},
  {9600, B9600},
  {19200, B19200},
  {38400, B38400},
  {-1, -1},
};

static int 
rate_to_code(rate)
     int rate;
{
  int i;

  for (i = 0; baudtab[i].rate != -1; i++)
    if (rate == baudtab[i].rate)  
      return baudtab[i].code;

  return -1;
}

static int
hardwire_setbaudrate(scb, rate)
     serial_t scb;
     int rate;
{
  struct hardwire_ttystate state;

  if (get_tty_state(scb, &state))
    return -1;

#ifdef HAVE_TERMIOS
  cfsetospeed (&state.termios, rate_to_code (rate));
  cfsetispeed (&state.termios, rate_to_code (rate));
#endif

#ifdef HAVE_TERMIO
#ifndef CIBAUD
#define CIBAUD CBAUD
#endif

  state.termio.c_cflag &= ~(CBAUD | CIBAUD);
  state.termio.c_cflag |= rate_to_code (rate);
#endif

#ifdef HAVE_SGTTY
  state.sgttyb.sg_ispeed = rate_to_code (rate);
  state.sgttyb.sg_ospeed = rate_to_code (rate);
#endif

  return set_tty_state (scb, &state);
}

static int
hardwire_set_process_group (scb, ttystate, group)
     serial_t scb;
     serial_ttystate ttystate;
     int group;
{
  ((struct hardwire_ttystate *)ttystate)->process_group = group;
  return 0;
}

static int
hardwire_write(scb, str, len)
     serial_t scb;
     const char *str;
     int len;
{
  int cc;

  while (len > 0)
    {
      cc = write(scb->fd, str, len);

      if (cc < 0)
	return 1;
      len -= cc;
      str += cc;
    }
  return 0;
}

static void
hardwire_close(scb)
     serial_t scb;
{
  if (scb->fd < 0)
    return;

  close(scb->fd);
  scb->fd = -1;
}

static struct serial_ops hardwire_ops =
{
  "hardwire",
  0,
  hardwire_open,
  hardwire_close,
  hardwire_readchar,
  hardwire_write,
  hardwire_flush_output,
  hardwire_raw,
  hardwire_get_tty_state,
  hardwire_set_tty_state,
  hardwire_print_tty_state,
  hardwire_noflush_set_tty_state,
  hardwire_setbaudrate,
  hardwire_set_process_group
};

int job_control;
#if defined (HAVE_TERMIOS)
#include <unistd.h>
#endif

/* This is here because this is where we figure out whether we (probably)
   have job control.  Just using job_control only does part of it because
   setpgid or setpgrp might not exist on a system without job control.
   It might be considered misplaced (on the other hand, process groups and
   job control are closely related to ttys).

   For a more clean implementation, in libiberty, put a setpgid which merely
   calls setpgrp and a setpgrp which does nothing (any system with job control
   will have one or the other).  */
int
gdb_setpgid ()
{
  int retval = 0;
  if (job_control)
    {
#if defined (NEED_POSIX_SETPGID) || defined (HAVE_TERMIOS)
      /* Do all systems with termios have setpgid?  I hope so.  */
      retval = setpgid (0, 0);
#else
#if defined (TIOCGPGRP)
#if defined(USG) && !defined(SETPGRP_ARGS)
      retval = setpgrp ();
#else
      retval = setpgrp (getpid (), getpid ());
#endif /* USG */
#endif /* TIOCGPGRP.  */
#endif /* NEED_POSIX_SETPGID */
    }
  return retval;
}

void
_initialize_ser_hardwire ()
{
  serial_add_interface (&hardwire_ops);

  /* OK, figure out whether we have job control.  */

#if defined (HAVE_TERMIOS)
  /* Do all systems with termios have the POSIX way of identifying job
     control?  I hope so.  */
#ifdef _POSIX_JOB_CONTROL
  /* AIX defines _POSIX_JOB_CONTROL to an empty string, so I guess
     defining _POSIX_JOB_CONTROL to 0 to mean no job control doesn't work
     (I don't have the standard handy).  */
  job_control = 1;
#else
  job_control = sysconf (_SC_JOB_CONTROL);
#endif

#else /* not termios.  */

#ifdef TIOCGPGRP
  job_control = 1;
#else
  job_control = 0;
#endif /* TIOCGPGRP */

#endif /* not termios.  */
}