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
|
/* some musl versions incorrectly mark fgetpwent() as a GNU extension */
#define _GNU_SOURCE
#include <assert.h> /* assert */
#include <errno.h> /* ENOENT, ERANGE */
#include <pthread.h> /* pthread_mutex_* */
#include <pwd.h> /* fgetpwent, getpwent, struct passwd */
#include <stddef.h> /* NULL, size_t */
#include <stdio.h> /* FILE */
#include <string.h> /* memcpy, stpcpy, strlcpy, strlen */
static pthread_mutex_t pwent_mutex = PTHREAD_MUTEX_INITIALIZER;
static int __fgetpwent_r(FILE *stream, struct passwd *pwd, char *buf,
size_t len, struct passwd **result)
{
struct passwd *pwtmp;
char *cursor = buf, *end = buf + len;
*result = NULL;
pthread_mutex_lock(&pwent_mutex);
pwtmp = stream != NULL ? fgetpwent(stream) : getpwent();
if (pwtmp == NULL) {
pthread_mutex_unlock(&pwent_mutex);
return ENOENT;
}
memcpy(pwd, pwtmp, sizeof(*pwd));
if (pwtmp->pw_name != NULL) {
pwd->pw_name = cursor;
cursor += strlcpy(cursor, pwtmp->pw_name, end - cursor) + 1;
if (cursor > end) {
goto err_unlock;
}
}
if (pwtmp->pw_passwd != NULL) {
pwd->pw_passwd = cursor;
cursor += strlcpy(cursor, pwtmp->pw_passwd, end - cursor) + 1;
if (cursor > end) {
goto err_unlock;
}
}
if (pwtmp->pw_gecos != NULL) {
pwd->pw_gecos = cursor;
cursor += strlcpy(cursor, pwtmp->pw_gecos, end - cursor) + 1;
if (cursor > end) {
goto err_unlock;
}
}
if (pwtmp->pw_dir != NULL) {
pwd->pw_dir = cursor;
cursor += strlcpy(cursor, pwtmp->pw_dir, end - cursor) + 1;
if (cursor > end) {
goto err_unlock;
}
}
if (pwtmp->pw_shell != NULL) {
pwd->pw_shell = cursor;
cursor += strlcpy(cursor, pwtmp->pw_shell, end - cursor) + 1;
if (cursor > end) {
goto err_unlock;
}
}
pthread_mutex_unlock(&pwent_mutex);
*result = pwd;
return 0;
err_unlock:
pthread_mutex_unlock(&pwent_mutex);
return ERANGE;
}
/**
* Get passwd file entry.
*/
int fgetpwent_r(FILE *stream, struct passwd *pwd, char *buf, size_t len,
struct passwd **result)
{
assert(stream != NULL);
return __fgetpwent_r(stream, pwd, buf, len, result);
}
/**
* Get user database entry.
*
* LSB 5.0: LSB-Core-generic/baselib-getpwent-r-1.html
*/
int getpwent_r(struct passwd *pwd, char *buf, size_t len,
struct passwd **result)
{
return __fgetpwent_r(NULL, pwd, buf, len, result);
}
|
