ubase/id.c
2014-06-30 19:04:47 +01:00

141 lines
2.3 KiB
C

/* See LICENSE file for copyright and license details. */
#include <sys/types.h>
#include <ctype.h>
#include <errno.h>
#include <grp.h>
#include <limits.h>
#include <pwd.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include "util.h"
static void groupid(struct passwd *pw);
static void user(struct passwd *pw);
static void userid(uid_t id);
static void usernam(const char *nam);
static void
usage(void)
{
eprintf("usage: %s [-g] [-u] [-G] [user | uid]\n", argv0);
}
static int Gflag = 0;
int
main(int argc, char *argv[])
{
ARGBEGIN {
case 'g':
printf("%d\n", getegid());
return EXIT_SUCCESS;
case 'u':
printf("%d\n", geteuid());
return EXIT_SUCCESS;
case 'G':
Gflag = 1;
break;
default:
usage();
} ARGEND;
errno = 0;
switch (argc) {
case 0:
userid(getuid());
break;
case 1:
/* user names can't begin [0-9] */
if (isdigit(argv[0][0]))
userid(estrtol(argv[0], 0));
else
usernam(argv[0]);
break;
default:
usage();
}
return EXIT_SUCCESS;
}
static void
groupid(struct passwd *pw)
{
gid_t gid, groups[NGROUPS_MAX];
int ngroups;
int i;
ngroups = NGROUPS_MAX;
getgrouplist(pw->pw_name, pw->pw_gid, groups, &ngroups);
for (i = 0; i < ngroups; i++) {
gid = groups[i];
printf("%u", gid);
if (i < ngroups - 1)
putchar(' ');
}
putchar('\n');
}
static void
usernam(const char *nam)
{
struct passwd *pw;
errno = 0;
pw = getpwnam(nam);
if (errno != 0)
eprintf("getpwnam %s:", nam);
else if (!pw)
eprintf("getpwnam %s: no such user\n", nam);
if (Gflag)
groupid(pw);
else
user(pw);
}
static void
userid(uid_t id)
{
struct passwd *pw;
errno = 0;
pw = getpwuid(id);
if (errno != 0)
eprintf("getpwuid %d:", id);
else if (!pw)
eprintf("getpwuid %d: no such user\n", id);
if (Gflag)
groupid(pw);
else
user(pw);
}
static void
user(struct passwd *pw)
{
struct group *gr;
gid_t gid, groups[NGROUPS_MAX];
int ngroups;
int i;
printf("uid=%u(%s)", pw->pw_uid, pw->pw_name);
printf(" gid=%u", pw->pw_gid);
if (!(gr = getgrgid(pw->pw_gid)))
eprintf("getgrgid:");
printf("(%s)", gr->gr_name);
ngroups = NGROUPS_MAX;
getgrouplist(pw->pw_name, pw->pw_gid, groups, &ngroups);
for (i = 0; i < ngroups; i++) {
gid = groups[i];
printf("%s%u", !i ? " groups=" : ",", gid);
if (!(gr = getgrgid(gid)))
eprintf("getgrgid:");
printf("(%s)", gr->gr_name);
}
putchar('\n');
}