1/*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
7 *
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or https://opensource.org/licenses/CDDL-1.0.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
12 *
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 *
19 * CDDL HEADER END
20 */
21/*
22 * Copyright 2006 Ricardo Correia.  All rights reserved.
23 * Use is subject to license terms.
24 */
25
26#include <unistd.h>
27#include <stdio.h>
28#include <errno.h>
29#include <stdlib.h>
30#include <limits.h>
31#include <string.h>
32
33#include <zone.h>
34
35zoneid_t
36getzoneid(void)
37{
38	char path[PATH_MAX];
39	char buf[128] = { '\0' };
40	char *cp;
41
42	int c = snprintf(path, sizeof (path), "/proc/self/ns/user");
43	/* This API doesn't have any error checking... */
44	if (c < 0 || c >= sizeof (path))
45		return (GLOBAL_ZONEID);
46
47	ssize_t r = readlink(path, buf, sizeof (buf) - 1);
48	if (r < 0)
49		return (GLOBAL_ZONEID);
50
51	cp = strchr(buf, '[');
52	if (cp == NULL)
53		return (GLOBAL_ZONEID);
54	cp++;
55
56	unsigned long n = strtoul(cp, NULL, 10);
57	if (n == ULONG_MAX && errno == ERANGE)
58		return (GLOBAL_ZONEID);
59	zoneid_t z = (zoneid_t)n;
60
61	return (z);
62}
63