1 /*
2 * Copyright (c) 1988, 1993
3 * The Regents of the University of California. All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 3. Neither the name of the University nor the names of its contributors
14 * may be used to endorse or promote products derived from this software
15 * without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 *
29 * $FreeBSD: src/lib/libc/gen/getlogin.c,v 1.4.2.1 2001/03/05 09:06:50 obrien Exp $
30 *
31 * @(#)getlogin.c 8.1 (Berkeley) 6/4/93
32 */
33
34 #include <sys/param.h>
35 #include <errno.h>
36 #include <pwd.h>
37 #include <stdio.h>
38 #include <string.h>
39 #include <unistd.h>
40 #include "namespace.h"
41 #include <pthread.h>
42 #include "un-namespace.h"
43
44 #include "libc_private.h"
45
46 #define THREAD_LOCK() if (__isthreaded) _pthread_mutex_lock(&logname_mutex)
47 #define THREAD_UNLOCK() if (__isthreaded) _pthread_mutex_unlock(&logname_mutex)
48
49 extern int _getlogin(char *, size_t);
50
51 int _logname_valid; /* known to setlogin() */
52 static pthread_mutex_t logname_mutex = PTHREAD_MUTEX_INITIALIZER;
53
54 static char *
getlogin_basic(int * status)55 getlogin_basic(int *status)
56 {
57 static char logname[MAXLOGNAME];
58
59 if (_logname_valid == 0) {
60 if (_getlogin(logname, sizeof(logname)) < 0) {
61 *status = errno;
62 return (NULL);
63 }
64 _logname_valid = 1;
65 }
66 *status = 0;
67 return (*logname ? logname : NULL);
68 }
69
70 char *
getlogin(void)71 getlogin(void)
72 {
73 char *result;
74 int status;
75
76 THREAD_LOCK();
77 result = getlogin_basic(&status);
78 THREAD_UNLOCK();
79 return (result);
80 }
81
82 int
getlogin_r(char * logname,size_t namelen)83 getlogin_r(char *logname, size_t namelen)
84 {
85 char *result;
86 size_t len;
87 int status;
88
89 THREAD_LOCK();
90 result = getlogin_basic(&status);
91 if (status == 0) {
92 if ((len = strlen(result) + 1) > namelen)
93 status = ERANGE;
94 else
95 strncpy(logname, result, len);
96 }
97 THREAD_UNLOCK();
98 return (status);
99 }
100