xref: /freebsd/lib/libc/gen/getlogin.c (revision 9768746b)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 1988, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. Neither the name of the University nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  */
31 
32 #include <sys/cdefs.h>
33 __SCCSID("@(#)getlogin.c	8.1 (Berkeley) 6/4/93");
34 __FBSDID("$FreeBSD$");
35 
36 #include <sys/param.h>
37 #include <errno.h>
38 #include <pwd.h>
39 #include <stdio.h>
40 #include <string.h>
41 #include <unistd.h>
42 #include "namespace.h"
43 #include <pthread.h>
44 #include "un-namespace.h"
45 
46 #include "libc_private.h"
47 
48 extern int		_getlogin(char *, int);
49 
50 char *
51 getlogin(void)
52 {
53 	static char logname[MAXLOGNAME];
54 
55 	if (_getlogin(logname, sizeof(logname)) < 0)
56 		return (NULL);
57 	return (logname[0] != '\0' ? logname : NULL);
58 }
59 
60 int
61 getlogin_r(char *logname, size_t namelen)
62 {
63 	char tmpname[MAXLOGNAME];
64 	int	len;
65 
66 	if (namelen < 1)
67 		return (ERANGE);
68 	logname[0] = '\0';
69 
70 	if (_getlogin(tmpname, sizeof(tmpname)) < 0)
71 		return (errno);
72 	len = strlen(tmpname) + 1;
73 	if (len > namelen)
74 		return (ERANGE);
75 	strlcpy(logname, tmpname, len);
76 	return (0);
77 }
78 
79 /* FreeBSD 12 and earlier compat. */
80 int
81 __getlogin_r_fbsd12(char *logname, int namelen)
82 {
83 	if (namelen < 1)
84 		return (ERANGE);
85 	return (getlogin_r(logname, namelen));
86 }
87 __sym_compat(getlogin_r, __getlogin_r_fbsd12, FBSD_1.0);
88