api.c revision a7469ce758fac3631df6ce72eb3f89150070e7f8 
1/*
2 * lib/route/link/api.c		Link Info API
3 *
4 *	This library is free software; you can redistribute it and/or
5 *	modify it under the terms of the GNU Lesser General Public
6 *	License as published by the Free Software Foundation version 2.1
7 *	of the License.
8 *
9 * Copyright (c) 2003-2008 Thomas Graf <tgraf@suug.ch>
10 */
11
12/**
13 * @ingroup link
14 * @defgroup link_info Link Info API
15 * @brief
16 *
17 * @par 1) Registering/Unregistering a new link info type
18 * @code
19 * static struct rtnl_link_info_ops vlan_info_ops = {
20 * 	.io_name		= "vlan",
21 * 	.io_alloc		= vlan_alloc,
22 * 	.io_parse		= vlan_parse,
23 * 	.io_dump[NL_DUMP_BRIEF]	= vlan_dump_brief,
24 * 	.io_dump[NL_DUMP_FULL]	= vlan_dump_full,
25 * 	.io_free		= vlan_free,
26 * };
27 *
28 * static void __init vlan_init(void)
29 * {
30 * 	rtnl_link_register_info(&vlan_info_ops);
31 * }
32 *
33 * static void __exit vlan_exit(void)
34 * {
35 * 	rtnl_link_unregister_info(&vlan_info_ops);
36 * }
37 * @endcode
38 *
39 * @{
40 */
41
42#include <netlink-local.h>
43#include <netlink/netlink.h>
44#include <netlink/utils.h>
45#include <netlink/route/link.h>
46#include <netlink/route/link/info-api.h>
47
48static struct rtnl_link_info_ops *info_ops;
49
50struct rtnl_link_info_ops *rtnl_link_info_ops_lookup(const char *name)
51{
52	struct rtnl_link_info_ops *ops;
53
54	for (ops = info_ops; ops; ops = ops->io_next)
55		if (!strcmp(ops->io_name, name))
56			return ops;
57
58	return NULL;
59}
60
61int rtnl_link_register_info(struct rtnl_link_info_ops *ops)
62{
63	if (ops->io_name == NULL)
64		return nl_error(EINVAL, "No name specified");
65
66	if (rtnl_link_info_ops_lookup(ops->io_name))
67		return nl_error(EEXIST, "Link info operations already exist");
68
69	NL_DBG(1, "Registered link info operations %s\n", ops->io_name);
70
71	ops->io_next = info_ops;
72	info_ops = ops;
73
74	return 0;
75}
76
77int rtnl_link_unregister_info(struct rtnl_link_info_ops *ops)
78{
79	struct rtnl_link_info_ops *t, **tp;
80
81	for (tp = &info_ops; (t=*tp) != NULL; tp = &t->io_next)
82		if (t == ops)
83			break;
84
85	if (!t)
86		return nl_error(ENOENT, "No such link info operations");
87
88	if (t->io_refcnt > 0)
89		return nl_error(EBUSY, "Info operations in use");
90
91	NL_DBG(1, "Unregistered link info perations %s\n", ops->io_name);
92
93	*tp = t->io_next;
94	return 0;
95}
96
97/** @} */
98
99