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
|
/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License (the "License").
* You may not use this file except in compliance with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* Copyright (c) 2017, Lawrence Livermore National Security, LLC.
*/
#include <fcntl.h>
#include <stdlib.h>
#include <stdio.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/systeminfo.h>
static unsigned long
get_spl_hostid(void)
{
FILE *f;
unsigned long hostid;
char *env;
/*
* Allow the hostid to be subverted for testing.
*/
env = getenv("ZFS_HOSTID");
if (env) {
hostid = strtoull(env, NULL, 0);
return (hostid & HOSTID_MASK);
}
f = fopen("/sys/module/spl/parameters/spl_hostid", "r");
if (!f)
return (0);
if (fscanf(f, "%lu", &hostid) != 1)
hostid = 0;
fclose(f);
return (hostid & HOSTID_MASK);
}
unsigned long
get_system_hostid(void)
{
unsigned long system_hostid = get_spl_hostid();
/*
* We do not use the library call gethostid() because
* it generates a hostid value that the kernel is
* unaware of, if the spl_hostid module parameter has not
* been set and there is no system hostid file (e.g.
* /etc/hostid). The kernel and userspace must agree.
* See comments above hostid_read() in the SPL.
*/
if (system_hostid == 0) {
int fd, rc;
unsigned long hostid;
int hostid_size = 4; /* 4 bytes regardless of arch */
fd = open("/etc/hostid", O_RDONLY);
if (fd >= 0) {
rc = read(fd, &hostid, hostid_size);
if (rc > 0)
system_hostid = (hostid & HOSTID_MASK);
close(fd);
}
}
return (system_hostid);
}
|
