shadow/lib/utent.c
Alejandro Colomar e2df287aad Don't redefine errno(3)
It is Undefined Behavior to declare errno (see NOTES in its manual page).
Instead of using the errno dummy declaration, use one that doesn't need
a comment.

Signed-off-by: Alejandro Colomar <alx@kernel.org>
2022-12-22 11:43:29 +01:00

71 lines
1.1 KiB
C

/*
* SPDX-FileCopyrightText: 1993 - 1994, Julianne Frances Haugh
* SPDX-FileCopyrightText: 1996 - 1998, Marek Michałkiewicz
* SPDX-FileCopyrightText: 2005 , Tomasz Kłoczko
*
* SPDX-License-Identifier: BSD-3-Clause
*/
#include <config.h>
#ifndef HAVE_GETUTENT
#include "defines.h"
#include <stdio.h>
#include <fcntl.h>
#include <utmp.h>
#ifndef lint
static char rcsid[] = "$Id$";
#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 ISO_C_forbids_an_empty_translation_unit;
#endif