getlogin.c revision 746f551ddc191f00808cd4121966c1ee42d5b74f
/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License (the "License").
* You may not use this file except in compliance with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* Copyright (c) 2013 Gary Mills
*
* Copyright 2008 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
/* Copyright (c) 1988 AT&T */
/* All Rights Reserved */
#pragma weak _getlogin = getloginx
#pragma weak _getlogin_r = getloginx_r
#include "lint.h"
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <string.h>
#include <stdlib.h>
#include <limits.h>
#include "utmpx.h"
#include <unistd.h>
#include <errno.h>
#include <thread.h>
#include <synch.h>
#include <mtlib.h>
#include "tsd.h"
/* Revert the renames done in unistd.h */
#ifdef __PRAGMA_REDEFINE_EXTNAME
#pragma redefine_extname getlogint getlogin
#pragma redefine_extname getlogint_r getlogin_r
#pragma redefine_extname __posix_getlogint_r __posix_getlogin_r
#else /* __PRAGMA_REDEFINE_EXTNAME */
#ifdef getlogin
#undef getlogin
#endif /* getlogin */
#ifdef getlogin_r
#undef getlogin_r
#endif /* getlogin_r */
#ifdef __posix_getlogin_r
#undef __posix_getlogin_r
#endif /* __posix_getlogin_r */
#define getlogint getlogin
#define getlogint_r getlogin_r
#define __posix_getlogint_r __posix_getlogin_r
#endif /* __PRAGMA_REDEFINE_EXTNAME */
extern char *getlogint(void);
extern char *getlogint_r(char *, int);
extern int __posix_getlogint_r(char *, int);
/*
* Use the full length of a login name.
* The utmpx interface provides for a 32 character login name.
*/
#define NMAX (sizeof (((struct utmpx *)0)->ut_user))
/*
* Common function
*/
static char *
getl_r_common(char *answer, size_t namelen, size_t maxlen)
{
int uf;
off64_t me;
struct futmpx ubuf;
if ((me = (off64_t)ttyslot()) < 0)
return (NULL);
if ((uf = open64(UTMPX_FILE, 0)) < 0)
return (NULL);
(void) lseek64(uf, me * sizeof (ubuf), SEEK_SET);
if (read(uf, &ubuf, sizeof (ubuf)) != sizeof (ubuf)) {
(void) close(uf);
return (NULL);
}
(void) close(uf);
if (ubuf.ut_user[0] == '\0')
return (NULL);
/* Insufficient buffer size */
if (namelen < strnlen(&ubuf.ut_user[0], maxlen)) {
errno = ERANGE;
return (NULL);
}
(void) strncpy(&answer[0], &ubuf.ut_user[0], maxlen);
answer[maxlen] = '\0';
return (&answer[0]);
}
/*
* POSIX.1c Draft-6 version of the function getlogin_r.
* It was implemented by Solaris 2.3.
*/
char *
getlogint_r(char *answer, int namelen)
{
return (getl_r_common(answer, (size_t)namelen, LOGNAME_MAX_TRAD));
}
/*
* POSIX.1c standard version of the function getlogin_r.
* User gets it via static getlogin_r from the header file.
*/
int
__posix_getlogint_r(char *name, int namelen)
{
int nerrno = 0;
int oerrno = errno;
errno = 0;
if (getl_r_common(name, (size_t)namelen, LOGNAME_MAX_TRAD) == NULL) {
if (errno == 0)
nerrno = EINVAL;
else
nerrno = errno;
}
errno = oerrno;
return (nerrno);
}
char *
getlogint(void)
{
char *answer = tsdalloc(_T_LOGIN, LOGIN_NAME_MAX_TRAD, NULL);
if (answer == NULL)
return (NULL);
return (getl_r_common(answer, LOGIN_NAME_MAX_TRAD, LOGNAME_MAX_TRAD));
}
/*
* POSIX.1c Draft-6 version of the function getlogin_r.
* It was implemented by Solaris 2.3.
* For extended login names, selected by redefine_extname in unistd.h.
*/
char *
getloginx_r(char *answer, int namelen)
{
return (getl_r_common(answer, (size_t)namelen, NMAX));
}
/*
* POSIX.1c standard version of the function getlogin_r.
* User gets it via static getlogin_r from the header file.
* For extended login names, selected by redefine_extname in unistd.h.
*/
int
__posix_getloginx_r(char *name, int namelen)
{
int nerrno = 0;
int oerrno = errno;
errno = 0;
if (getl_r_common(name, (size_t)namelen, NMAX) == NULL) {
if (errno == 0)
nerrno = EINVAL;
else
nerrno = errno;
}
errno = oerrno;
return (nerrno);
}
/*
* For extended login names, selected by redefine_extname in unistd.h.
*/
char *
getloginx(void)
{
char *answer = tsdalloc(_T_LOGIN, LOGIN_NAME_MAX, NULL);
if (answer == NULL)
return (NULL);
return (getl_r_common(answer, LOGIN_NAME_MAX, NMAX));
}