libnl  3.2.24-rc1
nl-monitor.c
1 /*
2  * src/nl-monitor.c Monitor events
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) 2003-2009 Thomas Graf <tgraf@suug.ch>
10  */
11 
12 #include <netlink/cli/utils.h>
13 #include <netlink/cli/link.h>
14 
15 static void obj_input(struct nl_object *obj, void *arg)
16 {
17  struct nl_dump_params dp = {
19  .dp_fd = stdout,
20  .dp_dump_msgtype = 1,
21  };
22 
23  nl_object_dump(obj, &dp);
24 }
25 
26 static int event_input(struct nl_msg *msg, void *arg)
27 {
28  if (nl_msg_parse(msg, &obj_input, NULL) < 0)
29  fprintf(stderr, "<<EVENT>> Unknown message type\n");
30 
31  /* Exit nl_recvmsgs_def() and return to the main select() */
32  return NL_STOP;
33 }
34 
35 int main(int argc, char *argv[])
36 {
37  struct nl_sock *sock;
38  struct nl_cache *link_cache;
39  int err = 1;
40  int i, idx;
41 
42  static const struct {
43  enum rtnetlink_groups gr_id;
44  const char* gr_name;
45  } known_groups[] = {
46  { RTNLGRP_LINK, "link" },
47  { RTNLGRP_NOTIFY, "notify" },
48  { RTNLGRP_NEIGH, "neigh" },
49  { RTNLGRP_TC, "tc" },
50  { RTNLGRP_IPV4_IFADDR, "ipv4-ifaddr" },
51  { RTNLGRP_IPV4_MROUTE, "ipv4-mroute" },
52  { RTNLGRP_IPV4_ROUTE, "ipv4-route" },
53  { RTNLGRP_IPV6_IFADDR, "ipv6-ifaddr" },
54  { RTNLGRP_IPV6_MROUTE, "ipv6-mroute" },
55  { RTNLGRP_IPV6_ROUTE, "ipv6-route" },
56  { RTNLGRP_IPV6_IFINFO, "ipv6-ifinfo" },
57  { RTNLGRP_DECnet_IFADDR, "decnet-ifaddr" },
58  { RTNLGRP_DECnet_ROUTE, "decnet-route" },
59  { RTNLGRP_IPV6_PREFIX, "ipv6-prefix" },
60  { RTNLGRP_NONE, NULL }
61  };
62 
63  sock = nl_cli_alloc_socket();
65  nl_socket_modify_cb(sock, NL_CB_VALID, NL_CB_CUSTOM, event_input, NULL);
66 
67  if (argc > 1 && !strcasecmp(argv[1], "-h")) {
68  printf("Usage: nl-monitor [<groups>]\n");
69 
70  printf("Known groups:");
71  for (i = 0; known_groups[i].gr_id != RTNLGRP_NONE; i++)
72  printf(" %s", known_groups[i].gr_name);
73  printf("\n");
74  return 2;
75  }
76 
77  nl_cli_connect(sock, NETLINK_ROUTE);
78 
79  for (idx = 1; argc > idx; idx++) {
80  for (i = 0; known_groups[i].gr_id != RTNLGRP_NONE; i++) {
81  if (!strcmp(argv[idx], known_groups[i].gr_name)) {
82 
83  if ((err = nl_socket_add_membership(sock, known_groups[i].gr_id)) < 0) {
84  nl_cli_fatal(err, "%s: %s\n", argv[idx],
85  nl_geterror(err));
86  }
87 
88  break;
89  }
90  }
91  if (known_groups[i].gr_id == RTNLGRP_NONE)
92  fprintf(stderr, "Warning: Unknown group: %s\n", argv[idx]);
93  }
94 
95  link_cache = nl_cli_link_alloc_cache(sock);
96 
97  while (1) {
98  fd_set rfds;
99  int fd, retval;
100 
101  fd = nl_socket_get_fd(sock);
102 
103  FD_ZERO(&rfds);
104  FD_SET(fd, &rfds);
105  /* wait for an incoming message on the netlink socket */
106  retval = select(fd+1, &rfds, NULL, NULL, NULL);
107 
108  if (retval) {
109  /* FD_ISSET(fd, &rfds) will be true */
110  nl_recvmsgs_default(sock);
111  }
112  }
113 
114  return 0;
115 }