blob: 02f9c7d6430e313038939df7b0d0c92ce1beb81e (
plain) (
blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
|
/* Copyright (C) 2009-2022 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<https://www.gnu.org/licenses/>. */
#include <errno.h>
#include <libc-lock.h>
#include <gshadow.h>
#include <stdio.h>
#include <stdlib.h>
/* A reasonable size for a buffer to start with. */
#define BUFLEN_SPWD 1024
/* We need to protect the dynamic buffer handling. */
__libc_lock_define_initialized (static, lock);
libc_freeres_ptr (static char *buffer);
/* Read one shadow entry from the given stream. */
struct sgrp *
fgetsgent (FILE *stream)
{
static size_t buffer_size;
static struct sgrp resbuf;
fpos_t pos;
struct sgrp *result;
int save;
if (fgetpos (stream, &pos) != 0)
return NULL;
/* Get lock. */
__libc_lock_lock (lock);
/* Allocate buffer if not yet available. */
if (buffer == NULL)
{
buffer_size = BUFLEN_SPWD;
buffer = malloc (buffer_size);
}
while (buffer != NULL
&& (__fgetsgent_r (stream, &resbuf, buffer, buffer_size, &result)
== ERANGE))
{
char *new_buf;
buffer_size += BUFLEN_SPWD;
new_buf = realloc (buffer, buffer_size);
if (new_buf == NULL)
{
/* We are out of memory. Free the current buffer so that the
process gets a chance for a normal termination. */
save = errno;
free (buffer);
__set_errno (save);
}
buffer = new_buf;
/* Reset the stream. */
if (fsetpos (stream, &pos) != 0)
buffer = NULL;
}
if (buffer == NULL)
result = NULL;
/* Release lock. Preserve error value. */
save = errno;
__libc_lock_unlock (lock);
__set_errno (save);
return result;
}
|