/* vi:set ts=8 sts=4 sw=4 noet:
 *
 * VIM - Vi IMproved		by Bram Moolenaar
 *
 * Do ":help uganda"  in Vim to read copying and usage conditions.
 * Do ":help credits" in Vim to see a list of people who contributed.
 * See README.txt for an overview of the Vim source code.
 */
/*
 * The stuff in this file mostly comes from the "screen" program.
 * Included with permission from Juergen Weigert.
 * Copied from "pty.c".  "putenv.c" was used for putenv() in misc2.c.
 *
 * It has been modified to work better with Vim.
 * The parts that are not used in Vim have been deleted.
 * See the "screen" sources for the complete stuff.
 *
 * This specific version is distibuted under the Vim license (attribution by
 * Juergen Weigert), the GPL applies to the original version, see the
 * copyright notice below.
 */

/* Copyright (c) 1993
 *	Juergen Weigert (jnweiger@immd4.informatik.uni-erlangen.de)
 *	Michael Schroeder (mlschroe@immd4.informatik.uni-erlangen.de)
 * Copyright (c) 1987 Oliver Laumann
 *
 * 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, 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 (see the file COPYING); if not, write to the
 * Free Software Foundation, Inc.,
 * 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA
 */

#include "vim.h"

#if defined(FEAT_JOB_CHANNEL)

#include <signal.h>

#ifdef __CYGWIN32__
#include <sys/termios.h>
#endif

#ifdef HAVE_SYS_IOCTL_H
#include <sys/ioctl.h>
#endif

#if HAVE_STROPTS_H
#include <sys/types.h>
#ifdef sinix
#define buf_T __system_buf_t__
#endif
#include <stropts.h>
#ifdef sinix
#undef buf_T
#endif
#ifdef SUN_SYSTEM
#include <sys/conf.h>
#if defined(HAVE_SYS_PTMS_H) && defined(HAVE_SVR4_PTYS)
#include <sys/ptms.h>
#endif
#endif
#endif

#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif

#if HAVE_TERMIO_H
#include <termio.h>
#else
#ifdef HAVE_TERMIOS_H
#include <termios.h>
#endif
#endif

#if HAVE_SYS_STREAM_H
#include <sys/stream.h>
#endif

#if HAVE_SYS_PTEM_H
#include <sys/ptem.h>
#endif

#if !defined(SUN_SYSTEM) && !defined(VMS)
#include <sys/ioctl.h>
#endif

#if defined(SUN_SYSTEM) && defined(LOCKPTY) && !defined(TIOCEXCL)
#include <sys/ttold.h>
#endif

#ifdef ISC
#include <sys/pty.h>
#include <sys/sioctl.h>
#include <sys/tty.h>
#endif

#ifdef sgi
#include <sys/sysmacros.h>
#endif

#if defined(_INCLUDE_HPUX_SOURCE) && !defined(hpux)
#define hpux
#endif

/*
 * if no PTYRANGE[01] is in the config file, we pick a default
 */
#ifndef PTYRANGE0
#define PTYRANGE0 "qprs"
#endif
#ifndef PTYRANGE1
#define PTYRANGE1 "0123456789abcdef"
#endif

/* SVR4 pseudo ttys don't seem to work with SCO-5 */
#ifdef M_UNIX
#undef HAVE_SVR4_PTYS
#endif

/*
 *  Open all ptys with O_NOCTTY, just to be on the safe side.
 */
#ifndef O_NOCTTY
#define O_NOCTTY 0
#endif

#if defined(HAVE_SVR4_PTYS) || defined(HAVE_POSIX_OPENPT)
// These should be in stdlib.h, but it depends on _XOPEN_SOURCE.
char *ptsname(int);
int unlockpt(int);
int grantpt(int);
int posix_openpt(int flags);
#endif

static void
initmaster(int f UNUSED)
{
#ifndef VMS
#ifdef POSIX
  tcflush(f, TCIOFLUSH);
#else
#ifdef TIOCFLUSH
  (void)ioctl(f, TIOCFLUSH, (char *)0);
#endif
#endif
#ifdef LOCKPTY
  (void)ioctl(f, TIOCEXCL, (char *)0);
#endif
#endif
}

/*
 * This causes a hang on some systems, but is required for a properly working
 * pty on others.  Needs to be tuned...
 */
int setup_slavepty(int fd)
{
  if (fd < 0)
    return 0;
#if defined(I_PUSH) && defined(HAVE_SVR4_PTYS) && !defined(sgi) && !defined(linux) && !defined(__osf__) && !defined(M_UNIX)
#if defined(HAVE_SYS_PTEM_H) || defined(hpux)
  if (ioctl(fd, I_PUSH, "ptem") != 0)
    return -1;
#endif
  if (ioctl(fd, I_PUSH, "ldterm") != 0)
    return -1;
#ifdef SUN_SYSTEM
  if (ioctl(fd, I_PUSH, "ttcompat") != 0)
    return -1;
#endif
#endif
  return 0;
}

#if defined(HAVE_POSIX_OPENPT) && !defined(PTY_DONE)
#define PTY_DONE
int mch_openpty(char **ttyn)
{
  int f;
  char *m;
  RETSIGTYPE(*sigcld)
  SIGPROTOARG;
  static char TtyName[32]; // used for opening a new pty-pair

  if ((f = posix_openpt(O_RDWR | O_NOCTTY | O_EXTRA)) == -1)
    return -1;

  // SIGCHLD set to SIG_DFL for grantpt() because it fork()s and
  // exec()s pt_chmod
  sigcld = signal(SIGCHLD, SIG_DFL);
  if ((m = ptsname(f)) == NULL || grantpt(f) || unlockpt(f))
  {
    signal(SIGCHLD, sigcld);
    close(f);
    return -1;
  }
  signal(SIGCHLD, sigcld);
  vim_strncpy((char_u *)TtyName, (char_u *)m, sizeof(TtyName) - 1);
  initmaster(f);
  *ttyn = TtyName;
  return f;
}
#endif

#if defined(OSX) && !defined(PTY_DONE)
#define PTY_DONE
int mch_openpty(char **ttyn)
{
  int f;
  static char TtyName[32];

  if ((f = open_controlling_pty(TtyName)) < 0)
    return -1;
  initmaster(f);
  *ttyn = TtyName;
  return f;
}
#endif

#if (defined(sequent) || defined(_SEQUENT_)) && defined(HAVE_GETPSEUDOTTY) && !defined(PTY_DONE)
#define PTY_DONE
int mch_openpty(char **ttyn)
{
  char *m, *s;
  int f;
  /* used for opening a new pty-pair: */
  static char PtyName[32];
  static char TtyName[32];

  if ((f = getpseudotty(&s, &m)) < 0)
    return -1;
#ifdef _SEQUENT_
  fvhangup(s);
#endif
  vim_strncpy((char_u *)PtyName, (char_u *)m, sizeof(PtyName) - 1);
  vim_strncpy((char_u *)TtyName, (char_u *)s, sizeof(TtyName) - 1);
  initmaster(f);
  *ttyn = TtyName;
  return f;
}
#endif

#if defined(__sgi) && !defined(PTY_DONE)
#define PTY_DONE
int mch_openpty(char **ttyn)
{
  int f;
  char *name;
  RETSIGTYPE(*sigcld)
  SIGPROTOARG;

  /*
     * SIGCHLD set to SIG_DFL for _getpty() because it may fork() and
     * exec() /usr/adm/mkpts
     */
  sigcld = signal(SIGCHLD, SIG_DFL);
  name = _getpty(&f, O_RDWR | O_NONBLOCK | O_EXTRA, 0600, 0);
  signal(SIGCHLD, sigcld);

  if (name == 0)
    return -1;
  initmaster(f);
  *ttyn = name;
  return f;
}
#endif

#if defined(MIPS) && defined(HAVE_DEV_PTC) && !defined(PTY_DONE)
#define PTY_DONE
int mch_openpty(char **ttyn)
{
  int f;
  stat_T buf;
  /* used for opening a new pty-pair: */
  static char TtyName[32];

  if ((f = open("/dev/ptc", O_RDWR | O_NOCTTY | O_NONBLOCK | O_EXTRA, 0)) < 0)
    return -1;
  if (mch_fstat(f, &buf) < 0)
  {
    close(f);
    return -1;
  }
  sprintf(TtyName, "/dev/ttyq%d", minor(buf.st_rdev));
  initmaster(f);
  *ttyn = TtyName;
  return f;
}
#endif

#if defined(HAVE_SVR4_PTYS) && !defined(PTY_DONE) && !defined(hpux) && !(defined(MACOS_X) && !defined(MAC_OS_X_VERSION_10_6))

/* NOTE: Even though HPUX can have /dev/ptmx, the code below doesn't work!
 * Same for Mac OS X Leopard (10.5). */
#define PTY_DONE
int mch_openpty(char **ttyn)
{
  int f;
  char *m;
  RETSIGTYPE(*sigcld)
  SIGPROTOARG;
  /* used for opening a new pty-pair: */
  static char TtyName[32];

  if ((f = open("/dev/ptmx", O_RDWR | O_NOCTTY | O_EXTRA, 0)) == -1)
    return -1;

  /*
     * SIGCHLD set to SIG_DFL for grantpt() because it fork()s and
     * exec()s pt_chmod
     */
  sigcld = signal(SIGCHLD, SIG_DFL);
  if ((m = ptsname(f)) == NULL || grantpt(f) || unlockpt(f))
  {
    signal(SIGCHLD, sigcld);
    close(f);
    return -1;
  }
  signal(SIGCHLD, sigcld);
  vim_strncpy((char_u *)TtyName, (char_u *)m, sizeof(TtyName) - 1);
  initmaster(f);
  *ttyn = TtyName;
  return f;
}
#endif

#if defined(_AIX) && defined(HAVE_DEV_PTC) && !defined(PTY_DONE)
#define PTY_DONE

#ifdef _IBMR2
int aixhack = -1;
#endif

int mch_openpty(char **ttyn)
{
  int f;
  /* used for opening a new pty-pair: */
  static char TtyName[32];

  /* a dumb looking loop replaced by mycrofts code: */
  if ((f = open("/dev/ptc", O_RDWR | O_NOCTTY | O_EXTRA)) < 0)
    return -1;
  vim_strncpy((char_u *)TtyName, (char_u *)ttyname(f), sizeof(TtyName) - 1);
  if (geteuid() != ROOT_UID && mch_access(TtyName, R_OK | W_OK))
  {
    close(f);
    return -1;
  }
  initmaster(f);
#ifdef _IBMR2
  if (aixhack >= 0)
    close(aixhack);
  if ((aixhack = open(TtyName, O_RDWR | O_NOCTTY | O_EXTRA, 0)) < 0)
  {
    close(f);
    return -1;
  }
#endif
  *ttyn = TtyName;
  return f;
}
#endif

#ifndef PTY_DONE

#ifdef hpux
static char PtyProto[] = "/dev/ptym/ptyXY";
static char TtyProto[] = "/dev/pty/ttyXY";
#else
#ifdef __BEOS__
static char PtyProto[] = "/dev/pt/XY";
static char TtyProto[] = "/dev/tt/XY";
#else
static char PtyProto[] = "/dev/ptyXY";
static char TtyProto[] = "/dev/ttyXY";
#endif
#endif

int mch_openpty(char **ttyn)
{
  char *p, *q, *l, *d;
  int f;
  /* used for opening a new pty-pair: */
  static char PtyName[32];
  static char TtyName[32];

  strcpy(PtyName, PtyProto);
  strcpy(TtyName, TtyProto);
  for (p = PtyName; *p != 'X'; p++)
    ;
  for (q = TtyName; *q != 'X'; q++)
    ;
  for (l = PTYRANGE0; (*p = *l) != '\0'; l++)
  {
    for (d = PTYRANGE1; (p[1] = *d) != '\0'; d++)
    {
      if ((f = open(PtyName, O_RDWR | O_NOCTTY | O_EXTRA, 0)) == -1)
        continue;
      q[0] = *l;
      q[1] = *d;
      if (geteuid() != ROOT_UID && mch_access(TtyName, R_OK | W_OK))
      {
        close(f);
        continue;
      }
#if defined(SUN_SYSTEM) && defined(TIOCGPGRP) && !defined(SUNOS3)
      /* Hack to ensure that the slave side of the pty is
	     * unused. May not work in anything other than SunOS4.1
	     */
      {
        int pgrp;

        /* tcgetpgrp does not work (uses TIOCGETPGRP)! */
        if (ioctl(f, TIOCGPGRP, (char *)&pgrp) != -1 || errno != EIO)
        {
          close(f);
          continue;
        }
      }
#endif
      initmaster(f);
      *ttyn = TtyName;
      return f;
    }
  }
  return -1;
}
#endif

/*
 * Call isatty(fd), except for SunOS where it's done differently.
 */
int mch_isatty(int fd)
{
#if defined(I_STR) && defined(HAVE_SYS_PTMS_H) && defined(HAVE_SVR4_PTYS) && defined(SUN_SYSTEM)
  // On SunOS, isatty() for /dev/ptmx returns false or sometimes can hang up
  // in the inner ioctl(), and therefore first determine whether "fd" is a
  // master device.
  struct strioctl istr;

  istr.ic_cmd = ISPTM;
  istr.ic_timout = 0;
  istr.ic_dp = NULL;
  istr.ic_len = 0;

  if (ioctl(fd, I_STR, &istr) == 0)
    // Trick: return 2 in order to advice the caller that "fd" is a master
    // device. cf. src/os_unix.c:get_tty_fd()
    return 2;
#endif
  return isatty(fd);
}

#endif /* FEAT_JOB_CHANNEL */