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
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
|
/*
* SPDX-FileCopyrightText: 1990 - 1994, Julianne Frances Haugh
* SPDX-FileCopyrightText: 1996 - 1998, Marek Michałkiewicz
* SPDX-FileCopyrightText: 2005 , Tomasz Kłoczko
* SPDX-FileCopyrightText: 2008 , Nicolas François
*
* SPDX-License-Identifier: BSD-3-Clause
*/
#include <config.h>
#ident "$Id$"
#include <stdio.h>
#include <sys/types.h>
#include <grp.h>
#include "defines.h"
#include "prototypes.h"
#define NFIELDS 4
/*
* list - turn a comma-separated string into an array of (char *)'s
*
* list() converts the comma-separated list of member names into
* an array of character pointers.
*
* WARNING: I profiled this once with and without strchr() calls
* and found that using a register variable and an explicit loop
* works best. For large /etc/group files, this is a major win.
*
* FINALLY added dynamic allocation. Still need to fix sgetsgent().
* --marekm
*/
static char **list (char *s)
{
static char **members = 0;
static int size = 0; /* max members + 1 */
int i;
char **rbuf;
i = 0;
for (;;) {
/* check if there is room for another pointer (to a group
member name, or terminating NULL). */
if (i >= size) {
size = i + 100; /* at least: i + 1 */
if (members) {
rbuf =
realloc (members, size * sizeof (char *));
} else {
/* for old (before ANSI C) implementations of
realloc() that don't handle NULL properly */
rbuf = malloc (size * sizeof (char *));
}
if (!rbuf) {
free (members);
members = 0;
size = 0;
return (char **) 0;
}
members = rbuf;
}
if (!s || s[0] == '\0')
break;
members[i++] = s;
while (('\0' != *s) && (',' != *s)) {
s++;
}
if ('\0' != *s) {
*s++ = '\0';
}
}
members[i] = (char *) 0;
return members;
}
struct group *sgetgrent (const char *buf)
{
static char *grpbuf = 0;
static size_t size = 0;
static char *grpfields[NFIELDS];
static struct group grent;
int i;
char *cp;
if (strlen (buf) + 1 > size) {
/* no need to use realloc() here - just free it and
allocate a larger block */
free (grpbuf);
size = strlen (buf) + 1000; /* at least: strlen(buf) + 1 */
grpbuf = malloc (size);
if (!grpbuf) {
size = 0;
return 0;
}
}
strcpy (grpbuf, buf);
cp = strrchr (grpbuf, '\n');
if (NULL != cp) {
*cp = '\0';
}
for (cp = grpbuf, i = 0; (i < NFIELDS) && (NULL != cp); i++) {
grpfields[i] = cp;
cp = strchr (cp, ':');
if (NULL != cp) {
*cp = '\0';
cp++;
}
}
if (i < (NFIELDS - 1) || *grpfields[2] == '\0' || cp != NULL) {
return (struct group *) 0;
}
grent.gr_name = grpfields[0];
grent.gr_passwd = grpfields[1];
if (get_gid (grpfields[2], &grent.gr_gid) == 0) {
return (struct group *) 0;
}
grent.gr_mem = list (grpfields[3]);
if (NULL == grent.gr_mem) {
return (struct group *) 0; /* out of memory */
}
return &grent;
}
|
