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
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
|
/*
* No copyright is claimed. This code is in the public domain; do with
* it what you wish.
*/
#include <stdlib.h>
#include <assert.h>
#include "c.h"
#include "pwdutils.h"
#include "xalloc.h"
/* Returns allocated passwd and allocated pwdbuf to store passwd strings
* fields. In case of error returns NULL and set errno, for unknown user set
* errno to EINVAL
*/
struct passwd *xgetpwnam(const char *username, char **pwdbuf)
{
struct passwd *pwd = NULL, *res = NULL;
int rc;
assert(pwdbuf);
assert(username);
*pwdbuf = xmalloc(UL_GETPW_BUFSIZ);
pwd = xcalloc(1, sizeof(struct passwd));
errno = 0;
rc = getpwnam_r(username, pwd, *pwdbuf, UL_GETPW_BUFSIZ, &res);
if (rc != 0) {
errno = rc;
goto failed;
}
if (!res) {
errno = EINVAL;
goto failed;
}
return pwd;
failed:
free(pwd);
free(*pwdbuf);
return NULL;
}
/* Returns allocated group and allocated grpbuf to store group strings
* fields. In case of error returns NULL and set errno, for unknown group set
* errno to EINVAL
*/
struct group *xgetgrnam(const char *groupname, char **grpbuf)
{
struct group *grp = NULL, *res = NULL;
int rc;
assert(grpbuf);
assert(groupname);
*grpbuf = xmalloc(UL_GETPW_BUFSIZ);
grp = xcalloc(1, sizeof(struct group));
errno = 0;
rc = getgrnam_r(groupname, grp, *grpbuf, UL_GETPW_BUFSIZ, &res);
if (rc != 0) {
errno = rc;
goto failed;
}
if (!res) {
errno = EINVAL;
goto failed;
}
return grp;
failed:
free(grp);
free(*grpbuf);
return NULL;
}
struct passwd *xgetpwuid(uid_t uid, char **pwdbuf)
{
struct passwd *pwd = NULL, *res = NULL;
int rc;
assert(pwdbuf);
*pwdbuf = xmalloc(UL_GETPW_BUFSIZ);
pwd = xcalloc(1, sizeof(struct passwd));
errno = 0;
rc = getpwuid_r(uid, pwd, *pwdbuf, UL_GETPW_BUFSIZ, &res);
if (rc != 0) {
errno = rc;
goto failed;
}
if (!res) {
errno = EINVAL;
goto failed;
}
return pwd;
failed:
free(pwd);
free(*pwdbuf);
return NULL;
}
char *xgetlogin(void)
{
struct passwd *pw = NULL;
uid_t ruid;
/* GNU Hurd implementation has an extension where a process can exist in a
* non-conforming environment, and thus be outside the realms of POSIX
* process identifiers; on this platform, getuid() fails with a status of
* (uid_t)(-1) and sets errno if a program is run from a non-conforming
* environment.
*
* http://austingroupbugs.net/view.php?id=511
*
* The same implementation is useful for other systems, since getlogin(3)
* shouldn't be used as actual identification.
*/
errno = 0;
ruid = getuid();
if (errno == 0)
pw = getpwuid(ruid);
if (pw && pw->pw_name && *pw->pw_name)
return xstrdup(pw->pw_name);
return NULL;
}
#ifdef TEST_PROGRAM
int main(int argc, char *argv[])
{
char *buf = NULL;
struct passwd *pwd = NULL;
if (argc != 2) {
fprintf(stderr, "usage: %s <username>\n", argv[0]);
return EXIT_FAILURE;
}
pwd = xgetpwnam(argv[1], &buf);
if (!pwd)
err(EXIT_FAILURE, "failed to get %s pwd entry", argv[1]);
printf("Username: %s\n", pwd->pw_name);
printf("UID: %d\n", pwd->pw_uid);
printf("HOME: %s\n", pwd->pw_dir);
printf("GECO: %s\n", pwd->pw_gecos);
free(pwd);
free(buf);
printf("Current: %s\n", (buf = xgetlogin()));
free(buf);
return EXIT_SUCCESS;
}
#endif /* TEST_PROGRAM */
|
