src/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) 2003-2006 Thomas Graf <tgraf@suug.ch>
  10  */
  11
  12 #include "utils.h"
  13 #include <netlink/route/link.h>
  14 #include <netlink/route/addr.h>
  15
  16 static void obj_input(struct nl_object *obj, void *arg)
  17 {
  18         struct nl_dump_params dp = {
  19                 .dp_type = NL_DUMP_STATS,
  20                 .dp_fd = stdout,
  21                 .dp_dump_msgtype = 1,
  22         };
  23
  24         nl_object_dump(obj, &dp);
  25 }
  26
  27 static int event_input(struct nl_msg *msg, void *arg)
  28 {
  29         if (nl_msg_parse(msg, &obj_input, NULL) < 0)
  30                 fprintf(stderr, "<<EVENT>> Unknown message type\n");
  31
  32         /* Exit nl_recvmsgs_def() and return to the main select() */
  33         return NL_STOP;
  34 }
  35
  36 int main(int argc, char *argv[])
  37 {
  38         struct nl_handle *nlh;
  39         struct nl_cache *link_cache;
  40         int err = 1;
  41         int i, idx;
  42
  43         static const struct {
  44                 enum rtnetlink_groups gr_id;
  45                 const char* gr_name;
  46         } known_groups[] = {
  47                 { RTNLGRP_LINK, "link" },
  48                 { RTNLGRP_NOTIFY, "notify" },
  49                 { RTNLGRP_NEIGH, "neigh" },
  50                 { RTNLGRP_TC, "tc" },
  51                 { RTNLGRP_IPV4_IFADDR, "ipv4-ifaddr" },
  52                 { RTNLGRP_IPV4_MROUTE, "ipv4-mroute" },
  53                 { RTNLGRP_IPV4_ROUTE, "ipv4-route" },
  54                 { RTNLGRP_IPV6_IFADDR, "ipv6-ifaddr" },
  55                 { RTNLGRP_IPV6_MROUTE, "ipv6-mroute" },
  56                 { RTNLGRP_IPV6_ROUTE, "ipv6-route" },
  57                 { RTNLGRP_IPV6_IFINFO, "ipv6-ifinfo" },
  58                 { RTNLGRP_DECnet_IFADDR, "decnet-ifaddr" },
  59                 { RTNLGRP_DECnet_ROUTE, "decnet-route" },
  60                 { RTNLGRP_IPV6_PREFIX, "ipv6-prefix" },
  61                 { RTNLGRP_NONE, NULL }
  62         };
  63
  64         if (nltool_init(argc, argv) < 0)
  65                 return -1;
  66
  67         nlh = nltool_alloc_handle();
  68         if (nlh == NULL)
  69                 return -1;
  70
  71         nl_disable_sequence_check(nlh);
  72
  73         nl_socket_modify_cb(nlh, NL_CB_VALID, NL_CB_CUSTOM, event_input, NULL);
  74
  75         if (argc > 1 && !strcasecmp(argv[1], "-h")) {
  76                 printf("Usage: nl-monitor [<groups>]\n");
  77
  78                 printf("Known groups:");
  79                 for (i = 0; known_groups[i].gr_id != RTNLGRP_NONE; i++)
  80                         printf(" %s", known_groups[i].gr_name);
  81                 printf("\n");
  82                 return 2;
  83         }
  84
  85         if (nl_connect(nlh, NETLINK_ROUTE) < 0) {
  86                 fprintf(stderr, "%s\n", nl_geterror());
  87                 goto errout;
  88         }
  89
  90         for (idx = 1; argc > idx; idx++) {
  91                 for (i = 0; known_groups[i].gr_id != RTNLGRP_NONE; i++) {
  92                         if (!strcmp(argv[idx], known_groups[i].gr_name)) {
  93
  94                                 if (nl_socket_add_membership(nlh, known_groups[i].gr_id) < 0) {
  95                                         fprintf(stderr, "%s: %s\n", argv[idx], nl_geterror());
  96                                         goto errout;
  97                                 }
  98
  99                                 break;
 100                         }
 101                 }
 102                 if (known_groups[i].gr_id == RTNLGRP_NONE)
 103                         fprintf(stderr, "Warning: Unknown group: %s\n", argv[idx]);
 104         }
 105
 106         if ((link_cache = rtnl_link_alloc_cache(nlh)) == NULL) {
 107                 fprintf(stderr, "%s\n", nl_geterror());
 108                 goto errout_close;
 109         }
 110
 111         nl_cache_mngt_provide(link_cache);
 112
 113         while (1) {
 114                 fd_set rfds;
 115                 int fd, retval;
 116
 117                 fd = nl_socket_get_fd(nlh);
 118
 119                 FD_ZERO(&rfds);
 120                 FD_SET(fd, &rfds);
 121                 /* wait for an incoming message on the netlink socket */
 122                 retval = select(fd+1, &rfds, NULL, NULL, NULL);
 123
 124                 if (retval) {
 125                         /* FD_ISSET(fd, &rfds) will be true */
 126                         nl_recvmsgs_default(nlh);
 127                 }
 128         }
 129
 130         nl_cache_free(link_cache);
 131 errout_close:
 132         nl_close(nlh);
 133 errout:
 134         return err;
 135 }