1/* Copyright (C) 1991-2023 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
3
4 The GNU C Library is free software; you can redistribute it and/or
5 modify it under the terms of the GNU Lesser General Public
6 License as published by the Free Software Foundation; either
7 version 2.1 of the License, or (at your option) any later version.
8
9 The GNU C Library is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 Lesser General Public License for more details.
13
14 You should have received a copy of the GNU Lesser General Public
15 License along with the GNU C Library; if not, see
16 <https://www.gnu.org/licenses/>. */
17
18#include <errno.h>
19#include <nss.h>
20#include <stdio.h>
21#include <string.h>
22#include <grp.h>
23
24#define flockfile(s) _IO_flockfile (s)
25#define funlockfile(s) _IO_funlockfile (s)
26
27#define _S(x) x ? x : ""
28
29/* Write an entry to the given stream.
30 This must know the format of the group file. */
31int
32putgrent (const struct group *gr, FILE *stream)
33{
34 int retval;
35
36 if (__glibc_unlikely (gr == NULL) || __glibc_unlikely (stream == NULL)
37 || gr->gr_name == NULL || !__nss_valid_field (gr->gr_name)
38 || !__nss_valid_field (gr->gr_passwd)
39 || !__nss_valid_list_field (gr->gr_mem))
40 {
41 __set_errno (EINVAL);
42 return -1;
43 }
44
45 flockfile (stream);
46
47 if (gr->gr_name[0] == '+' || gr->gr_name[0] == '-')
48 retval = fprintf (stream, "%s:%s::",
49 gr->gr_name, _S (gr->gr_passwd));
50 else
51 retval = fprintf (stream, "%s:%s:%lu:",
52 gr->gr_name, _S (gr->gr_passwd),
53 (unsigned long int) gr->gr_gid);
54 if (__builtin_expect (retval, 0) < 0)
55 {
56 funlockfile (stream);
57 return -1;
58 }
59
60 if (gr->gr_mem != NULL)
61 {
62 for (size_t i = 0; gr->gr_mem[i] != NULL; i++)
63 if (fprintf (stream, i == 0 ? "%s" : ",%s", gr->gr_mem[i]) < 0)
64 {
65 /* What else can we do? */
66 funlockfile (stream);
67 return -1;
68 }
69 }
70
71 retval = fputc_unlocked ('\n', stream);
72
73 funlockfile (stream);
74
75 return retval < 0 ? -1 : 0;
76}
77