ubase/id.c
2015-04-26 10:40:09 +01:00

177 lines
2.9 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 int gflag = 0;
static int uflag = 0;
static int Gflag = 0;
static int nflag = 0;
static void
groupid(struct passwd *pw)
{
gid_t gid, groups[NGROUPS_MAX];
struct group *gr;
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];
if (nflag) {
if (!(gr = getgrgid(gid)))
eprintf("getgrgid:");
printf("%s", gr->gr_name);
} else
printf("%u", gid);
if (i < ngroups - 1)
putchar(' ');
}
putchar('\n');
}
static void
user(struct passwd *pw)
{
struct group *gr;
gid_t gid, groups[NGROUPS_MAX];
int ngroups;
int i;
if (uflag) {
if (nflag)
printf("%s\n", pw->pw_name);
else
printf("%u\n", pw->pw_uid);
return;
} else if (gflag) {
if (nflag) {
if (!(gr = getgrgid(pw->pw_gid)))
eprintf("getgrgid:");
printf("%s\n", gr->gr_name);
} else
printf("%u\n", pw->pw_gid);
return;
}
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');
}
static void
usernam(const char *nam)
{
struct passwd *pw;
errno = 0;
pw = getpwnam(nam);
if (!pw) {
if (errno)
eprintf("getpwnam %s:", nam);
else
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 (!pw) {
if (errno)
eprintf("getpwuid %d:", id);
else
eprintf("getpwuid %d: no such user\n", id);
}
if (Gflag)
groupid(pw);
else
user(pw);
}
static void
usage(void)
{
eprintf("usage: %s [-n] [-g | -u | -G] [user | uid]\n", argv0);
}
int
main(int argc, char *argv[])
{
ARGBEGIN {
case 'g':
gflag = 1;
break;
case 'u':
uflag = 1;
break;
case 'G':
Gflag = 1;
break;
case 'n':
nflag = 1;
break;
default:
usage();
} ARGEND;
/* ensure that only one of -g, -u, or -G was specified */
if (gflag + uflag + Gflag > 1)
usage();
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 0;
}