1/* Copyright (C) 1997-2021 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
3 Contributed by Mark Kettenis <kettenis@phys.uva.nl>, 1997.
4
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Lesser General Public
7 License as published by the Free Software Foundation; either
8 version 2.1 of the License, or (at your option) any later version.
9
10 The GNU C Library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Lesser General Public License for more details.
14
15 You should have received a copy of the GNU Lesser General Public
16 License along with the GNU C Library; if not, see
17 <https://www.gnu.org/licenses/>. */
18
19#include <libc-lock.h>
20#include <stdlib.h>
21#include <string.h>
22#include <utmp.h>
23
24#include "utmp-private.h"
25
26
27/* This is the default name. */
28static const char default_file_name[] = _PATH_UTMP;
29
30/* Current file name. */
31const char *__libc_utmp_file_name = (const char *) default_file_name;
32
33/* We have to use the lock in getutent_r.c. */
34__libc_lock_define (extern, __libc_utmp_lock attribute_hidden)
35
36
37int
38__utmpname (const char *file)
39{
40 int result = -1;
41
42 __libc_lock_lock (__libc_utmp_lock);
43
44 /* Close the old file. */
45 __libc_endutent ();
46
47 if (strcmp (file, __libc_utmp_file_name) != 0)
48 {
49 if (strcmp (file, default_file_name) == 0)
50 {
51 free ((char *) __libc_utmp_file_name);
52
53 __libc_utmp_file_name = default_file_name;
54 }
55 else
56 {
57 char *file_name = __strdup (file);
58 if (file_name == NULL)
59 /* Out of memory. */
60 goto done;
61
62 if (__libc_utmp_file_name != default_file_name)
63 free ((char *) __libc_utmp_file_name);
64
65 __libc_utmp_file_name = file_name;
66 }
67 }
68
69 result = 0;
70
71done:
72 __libc_lock_unlock (__libc_utmp_lock);
73 return result;
74}
75weak_alias (__utmpname, utmpname)
76