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/*
 * Copyright (c) 1993 - 1994, Julianne Frances Haugh
 * Copyright (c) 1996 - 1998, Marek Michałkiewicz
 * Copyright (c) 2005       , Tomasz Kłoczko
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. The name of the copyright holders or contributors may not be used to
 *    endorse or promote products derived from this software without
 *    specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
 * PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT
 * HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include <config.h>

#ifndef	HAVE_GETUTENT

#include "defines.h"
#include <stdio.h>
#include <fcntl.h>
#include <utmp.h>

#ifndef	lint
static char rcsid[] = "$Id: utent.c 3181 2010-03-23 08:56:52Z nekral-guest $";
#endif

static int utmp_fd = -1;
static struct utmp utmp_buf;

/*
 * setutent - open or rewind the utmp file
 */

void setutent (void)
{
	if (utmp_fd == -1)
		if ((utmp_fd = open (_UTMP_FILE, O_RDWR)) == -1)
			utmp_fd = open (_UTMP_FILE, O_RDONLY);

	if (utmp_fd != -1)
		lseek (utmp_fd, (off_t) 0L, SEEK_SET);
}

/*
 * endutent - close the utmp file
 */

void endutent (void)
{
	if (utmp_fd != -1)
		close (utmp_fd);

	utmp_fd = -1;
}

/*
 * getutent - get the next record from the utmp file
 */

struct utmp *getutent (void)
{
	if (utmp_fd == -1)
		setutent ();

	if (utmp_fd == -1)
		return 0;

	if (read (utmp_fd, &utmp_buf, sizeof utmp_buf) != sizeof utmp_buf)
		return 0;

	return &utmp_buf;
}
#else
extern int errno;		/* warning: ANSI C forbids an empty source file */
#endif