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_EXIT;
  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_FIB_MAGIC, "fib-magic" },
  62                 { RTNLGRP_NONE, NULL }
  63         };
  64
  65         if (nltool_init(argc, argv) < 0)
  66                 return -1;
  67
  68         nlh = nl_handle_alloc_nondefault(nltool_cbset);
  69         if (nlh == NULL)
  70                 return -1;
  71
  72         nl_disable_sequence_check(nlh);
  73
  74         nl_cb_set(nl_handle_get_cb(nlh), NL_CB_VALID, NL_CB_CUSTOM,
  75                   event_input, NULL);
  76
  77         if (argc > 1 && !strcasecmp(argv[1], "-h")) {
  78                 printf("Usage: nl-monitor [<groups>]\n");
  79
  80                 printf("Known groups:");
  81                 for (i = 0; known_groups[i].gr_id != RTNLGRP_NONE; i++)
  82                         printf(" %s", known_groups[i].gr_name);
  83                 printf("\n");
  84                 return 2;
  85         }
  86
  87         nl_join_groups(nlh, RTMGRP_LINK);
  88
  89         if (nl_connect(nlh, NETLINK_ROUTE) < 0) {
  90                 fprintf(stderr, "%s\n", nl_geterror());
  91                 goto errout;
  92         }
  93
  94         for (idx = 1; argc > idx; idx++) {
  95                 for (i = 0; known_groups[i].gr_id != RTNLGRP_NONE; i++) {
  96                         if (!strcmp(argv[idx], known_groups[i].gr_name)) {
  97
  98                                 if (nl_join_group(nlh, known_groups[i].gr_id) < 0) {
  99                                         fprintf(stderr, "%s: %s\n", argv[idx], nl_geterror());
 100                                         goto errout;
 101                                 }
 102
 103                                 break;
 104                         }
 105                 }
 106                 if (known_groups[i].gr_id == RTNLGRP_NONE)
 107                         fprintf(stderr, "Warning: Unknown group: %s\n", argv[idx]);
 108         }
 109
 110         if ((link_cache = rtnl_link_alloc_cache(nlh)) == NULL) {
 111                 fprintf(stderr, "%s\n", nl_geterror());
 112                 goto errout_close;
 113         }
 114
 115         nl_cache_mngt_provide(link_cache);
 116
 117         while (1) {
 118                 fd_set rfds;
 119                 int fd, retval;
 120
 121                 fd = nl_handle_get_fd(nlh);
 122
 123                 FD_ZERO(&rfds);
 124                 FD_SET(fd, &rfds);
 125                 /* wait for an incoming message on the netlink socket */
 126                 retval = select(fd+1, &rfds, NULL, NULL, NULL);
 127
 128                 if (retval) {
 129                         /* FD_ISSET(fd, &rfds) will be true */
 130                         nl_recvmsgs_def(nlh);
 131                 }
 132         }
 133
 134         nl_cache_free(link_cache);
 135 errout_close:
 136         nl_close(nlh);
 137 errout:
 138         return err;
 139 }