/*
   * Copyright (C) 2002 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)

   * Licensed under the GPL
   */
  
  #include <stdlib.h>

  #include <unistd.h>

  #include <errno.h>

  #include <fcntl.h>

  #include "kern_util.h"

  #include "os.h"

  
  struct grantpt_info {
  	int fd;
  	int res;
  	int err;
  };
  
  static void grantpt_cb(void *arg)
  {
  	struct grantpt_info *info = arg;
  
  	info->res = grantpt(info->fd);
  	info->err = errno;
  }
  
  int get_pty(void)
  {
  	struct grantpt_info info;

  	int fd, err;
  
  	fd = open("/dev/ptmx", O_RDWR);
  	if (fd < 0) {
  		err = -errno;
  		printk(UM_KERN_ERR "get_pty : Couldn't open /dev/ptmx - "
  		       "err = %d
  ", errno);
  		return err;

  	}
  
  	info.fd = fd;
  	initial_thread_cb(grantpt_cb, &info);

  	if (info.res < 0) {
  		err = -info.err;
  		printk(UM_KERN_ERR "get_pty : Couldn't grant pty - "
  		       "errno = %d
  ", -info.err);
  		goto out;

  	}

  
  	if (unlockpt(fd) < 0) {
  		err = -errno;
  		printk(UM_KERN_ERR "get_pty : Couldn't unlock pty - "
  		       "errno = %d
  ", errno);
  		goto out;

  	}

  	return fd;
  out:
  	close(fd);
  	return err;

  }