/* Copyright (C) 1998-2018 Free Software Foundation, Inc.

   This file is part of the GNU C Library.

   Contributed by Zack Weinberg <zack@rabi.phys.columbia.edu>, 1998.

   The GNU C Library is free software; you can redistribute it and/or

   modify it under the terms of the GNU Lesser General Public

   License as published by the Free Software Foundation; either

   version 2.1 of the License, or (at your option) any later version.

   The GNU C Library 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

   Lesser General Public License for more details.

   You should have received a copy of the GNU Lesser General Public

   License along with the GNU C Library; if not, see

   <http://www.gnu.org/licenses/>.  */

#include <errno.h>

#include <fcntl.h>

#include <stdlib.h>

#include <unistd.h>

#include <paths.h>

#include <sys/statfs.h>

#include "linux_fsinfo.h"

/* Path to the master pseudo terminal cloning device.  */

#define _PATH_DEVPTMX _PATH_DEV "ptmx"

/* Directory containing the UNIX98 pseudo terminals.  */

#define _PATH_DEVPTS _PATH_DEV "pts"

/* Prototype for function that opens BSD-style master pseudo-terminals.  */

extern int __bsd_getpt (void) attribute_hidden;

/* Open a master pseudo terminal and return its file descriptor.  */

int

__posix_openpt (int oflag)

{

  static int have_no_dev_ptmx;

  int fd;

  if (!have_no_dev_ptmx)

    {

      fd = __open (_PATH_DEVPTMX, oflag);

      if (fd != -1)

	{

	  struct statfs fsbuf;

	  static int devpts_mounted;

	  /* Check that the /dev/pts filesystem is mounted

	     or if /dev is a devfs filesystem (this implies /dev/pts).  */

	  if (devpts_mounted

	      || (__statfs (_PATH_DEVPTS, &fsbuf) == 0

		  && fsbuf.f_type == DEVPTS_SUPER_MAGIC)

	      || (__statfs (_PATH_DEV, &fsbuf) == 0

		  && fsbuf.f_type == DEVFS_SUPER_MAGIC))

	    {

	      /* Everything is ok.  */

	      devpts_mounted = 1;

	      return fd;

	    }

	  /* If /dev/pts is not mounted then the UNIX98 pseudo terminals

	     are not usable.  */

	  __close (fd);

	  have_no_dev_ptmx = 1;

	  __set_errno (ENOENT);

	}

      else

	{

	  if (errno == ENOENT || errno == ENODEV)

	    have_no_dev_ptmx = 1;

	  else

	    return -1;

	}

    }

  else

    __set_errno (ENOENT);

  return -1;

}

weak_alias (__posix_openpt, posix_openpt)

int

__getpt (void)

{

  int fd = __posix_openpt (O_RDWR);

  if (fd == -1)

    fd = __bsd_getpt ();

  return fd;

}

#define PTYNAME1 "pqrstuvwxyzabcde";

#define PTYNAME2 "0123456789abcdef";

#define __getpt __bsd_getpt

#define HAVE_POSIX_OPENPT

#include <sysdeps/unix/bsd/getpt.c>