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
|
#include "command.h"
#include "lslib.h"
#include <grp.h>
#include <pwd.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <errno.h>
static void help (void) {
printf("Usage: id [USER]\n\n");
printf("Print information about the USER\n");
}
COMMAND(user_id) {
uid_t uid;
gid_t gid, *groups;
int ngroups, i;
struct passwd* pw;
struct group* ugr;
parse_help(argc, argv, help);
if (argc < 1) {
uid = getuid();
pw = getpwuid(uid);
} else {
pw = getpwnam(argv[0]);
}
if(pw == NULL){
if (errno == 0) {
error("user not found");
} else {
error("failed to fetch groups");
}
}
uid = pw->pw_uid;
ngroups = 0;
getgrouplist(pw->pw_name, pw->pw_gid, NULL, &ngroups);
groups = xalloc(sizeof(gid_t) * ngroups);
getgrouplist(pw->pw_name, pw->pw_gid, groups, &ngroups);
gid = pw->pw_gid;
ugr = getgrgid(gid);
printf("uid=%d(%s) gid=%d(%s) ",
uid, ugr->gr_name, gid, ugr->gr_name);
if (ngroups > 0) {
printf("groups=");
}
for (i = 0; i < ngroups; i++){
struct group* gr = getgrgid(groups[i]);
if(gr == NULL) {
free(groups);
error("failed to fetch groups");
}
printf("%d(%s)", gr->gr_gid, gr->gr_name);
if (i + 1 < ngroups) putchar(',');
}
printf("\b\n");
free(groups);
return EXIT_SUCCESS;
}
|
