libnl 3.5.0

nl-monitor.c
1 /* SPDX-License-Identifier: LGPL-2.1-only */
2 /*
3 * src/nl-monitor.c Monitor events
4 *
5 * This library is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU Lesser General Public
7 * License as published by the Free Software Foundation version 2.1
8 * of the License.
9 *
10 * Copyright (c) 2003-2009 Thomas Graf <tgraf@suug.ch>
11 */
12
13 #include <netlink/cli/utils.h>
14 #include <netlink/cli/link.h>
15
16 #include <linux/rtnetlink.h>
17
18 static const struct {
19 enum rtnetlink_groups gr_id;
20 const char* gr_name;
21 } known_groups[] = {
22 { RTNLGRP_LINK, "link" },
23 { RTNLGRP_NOTIFY, "notify" },
24 { RTNLGRP_NEIGH, "neigh" },
25 { RTNLGRP_TC, "tc" },
26 { RTNLGRP_IPV4_IFADDR, "ipv4-ifaddr" },
27 { RTNLGRP_IPV4_MROUTE, "ipv4-mroute" },
28 { RTNLGRP_IPV4_ROUTE, "ipv4-route" },
29 { RTNLGRP_IPV6_IFADDR, "ipv6-ifaddr" },
30 { RTNLGRP_IPV6_MROUTE, "ipv6-mroute" },
31 { RTNLGRP_IPV6_ROUTE, "ipv6-route" },
32 { RTNLGRP_IPV6_IFINFO, "ipv6-ifinfo" },
33 { RTNLGRP_DECnet_IFADDR, "decnet-ifaddr" },
34 { RTNLGRP_DECnet_ROUTE, "decnet-route" },
35 { RTNLGRP_IPV6_PREFIX, "ipv6-prefix" },
36 { RTNLGRP_IPV4_NETCONF, "ipv4-netconf" },
37 { RTNLGRP_IPV6_NETCONF, "ipv6-netconf" },
38 { RTNLGRP_MPLS_NETCONF, "mpls-netconf" },
39 { RTNLGRP_NONE, NULL }
40 };
41
42 static void obj_input(struct nl_object *obj, void *arg)
43 {
44 nl_object_dump(obj, arg);
45 }
46
47 static int event_input(struct nl_msg *msg, void *arg)
48 {
49 if (nl_msg_parse(msg, &obj_input, arg) < 0)
50 fprintf(stderr, "<<EVENT>> Unknown message type\n");
51
52 /* Exit nl_recvmsgs_def() and return to the main select() */
53 return NL_STOP;
54 }
55
56 static void print_usage(void)
57 {
58 int i;
59
60 printf(
61 "Usage: nl-monitor [OPTION] [<groups>]\n"
62 "\n"
63 "Options\n"
64 " -f, --format=TYPE Output format { brief | details | stats }\n"
65 " -h, --help Show this help.\n"
66 "\n"
67 );
68 printf("Known groups:");
69 for (i = 0; known_groups[i].gr_id != RTNLGRP_NONE; i++)
70 printf(" %s", known_groups[i].gr_name);
71 printf("\n");
72 exit(0);
73 }
74
75 int main(int argc, char *argv[])
76 {
77 struct nl_dump_params dp = {
78 .dp_type = NL_DUMP_STATS,
79 .dp_fd = stdout,
80 .dp_dump_msgtype = 1,
81 };
82
83 struct nl_sock *sock;
84 int err = 1;
85 int i, idx;
86
87 sock = nl_cli_alloc_socket();
88 nl_socket_disable_seq_check(sock);
89 nl_socket_modify_cb(sock, NL_CB_VALID, NL_CB_CUSTOM, event_input, &dp);
90
91 for (;;) {
92 int c, optidx = 0;
93 static struct option long_opts[] = {
94 { "format", 1, 0, 'f' },
95 { 0, 0, 0, 0 }
96 };
97
98 c = getopt_long(argc, argv, "f:h", long_opts, &optidx);
99 if (c == -1)
100 break;
101
102 switch (c) {
103 case 'f':
104 dp.dp_type = nl_cli_parse_dumptype(optarg);
105 break;
106 default:
107 print_usage();
108 break;
109 }
110 }
111
112 nl_cli_connect(sock, NETLINK_ROUTE);
113
114 for (idx = optind; argc > idx; idx++) {
115 for (i = 0; known_groups[i].gr_id != RTNLGRP_NONE; i++) {
116 if (!strcmp(argv[idx], known_groups[i].gr_name)) {
117
118 if ((err = nl_socket_add_membership(sock, known_groups[i].gr_id)) < 0) {
119 nl_cli_fatal(err, "%s: %s\n", argv[idx],
120 nl_geterror(err));
121 }
122
123 break;
124 }
125 }
126 if (known_groups[i].gr_id == RTNLGRP_NONE)
127 fprintf(stderr, "Warning: Unknown group: %s\n", argv[idx]);
128 }
129
130 nl_cli_link_alloc_cache(sock);
131
132 while (1) {
133 fd_set rfds;
134 int fd, retval;
135
136 fd = nl_socket_get_fd(sock);
137
138 FD_ZERO(&rfds);
139 FD_SET(fd, &rfds);
140 /* wait for an incoming message on the netlink socket */
141 retval = select(fd+1, &rfds, NULL, NULL, NULL);
142
143 if (retval) {
144 /* FD_ISSET(fd, &rfds) will be true */
145 nl_recvmsgs_default(sock);
146 }
147 }
148
149 return 0;
150 }
NL_CB_CUSTOM
Customized handler specified by the user.
Definition: handlers.h:83
nl_socket_get_fd
int nl_socket_get_fd(const struct nl_sock *sk)
Return the file descriptor of the backing socket.
Definition: socket.c:584
nl_dump_params::dp_type
enum nl_dump_type dp_type
Specifies the type of dump that is requested.
Definition: types.h:38
NL_STOP
Stop parsing altogether and discard remaining messages.
Definition: handlers.h:68
nl_socket_modify_cb
int nl_socket_modify_cb(struct nl_sock *sk, enum nl_cb_type type, enum nl_cb_kind kind, nl_recvmsg_msg_cb_t func, void *arg)
Modify the callback handler associated with the socket.
Definition: socket.c:771
nl_object_dump
void nl_object_dump(struct nl_object *obj, struct nl_dump_params *params)
Dump this object according to the specified parameters.
Definition: object.c:289
nl_socket_disable_seq_check
void nl_socket_disable_seq_check(struct nl_sock *sk)
Disable sequence number checking.
Definition: socket.c:283
nl_recvmsgs_default
int nl_recvmsgs_default(struct nl_sock *sk)
Receive a set of message from a netlink socket using handlers in nl_sock.
Definition: nl.c:1094
NL_CB_VALID
Message is valid.
Definition: handlers.h:95
nl_cli_fatal
void nl_cli_fatal(int err, const char *fmt,...)
Print error message and quit application.
Definition: utils.c:78
nl_dump_params
Dumping parameters.
Definition: types.h:33
NL_DUMP_STATS
Dump all attributes including statistics.
Definition: types.h:24