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/* $OpenBSD: login.c,v 1.10 2005/08/02 21:46:23 espie Exp $ */
/*
* Copyright (c) 1988, 1993
* The Regents of the University of California. 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. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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 <sys/types.h>
#include <fcntl.h>
#include <unistd.h>
#include <stdlib.h>
#include <utmp.h>
#include <stdio.h>
#include <string.h>
#include "util.h"
void
login(struct utmp *utp)
{
struct utmp old_ut;
register int fd;
int tty;
tty = ttyslot();
if (tty > 0 && (fd = open(_PATH_UTMP, O_RDWR|O_CREAT, 0644)) >= 0) {
(void)lseek(fd, (off_t)(tty * sizeof(struct utmp)), SEEK_SET);
/*
* Prevent luser from zero'ing out ut_host.
* If the new ut_line is empty but the old one is not
* and ut_line and ut_name match, preserve the old ut_line.
*/
if (read(fd, &old_ut, sizeof(struct utmp)) ==
sizeof(struct utmp) && utp->ut_host[0] == '\0' &&
old_ut.ut_host[0] != '\0' &&
strncmp(old_ut.ut_line, utp->ut_line, UT_LINESIZE) == 0 &&
strncmp(old_ut.ut_name, utp->ut_name, UT_NAMESIZE) == 0)
(void)memcpy(utp->ut_host, old_ut.ut_host, UT_HOSTSIZE);
(void)lseek(fd, (off_t)(tty * sizeof(struct utmp)), SEEK_SET);
(void)write(fd, utp, sizeof(struct utmp));
(void)close(fd);
}
if ((fd = open(_PATH_WTMP, O_WRONLY|O_APPEND, 0)) >= 0) {
(void)write(fd, utp, sizeof(struct utmp));
(void)close(fd);
}
}
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