lib/rtnetlink.h

   1 /*
   2  * Copyright (c) 2009 Nicira Networks.
   3  *
   4  * Licensed under the Apache License, Version 2.0 (the "License");
   5  * you may not use this file except in compliance with the License.
   6  * You may obtain a copy of the License at:
   7  *
   8  *     http://www.apache.org/licenses/LICENSE-2.0
   9  *
  10  * Unless required by applicable law or agreed to in writing, software
  11  * distributed under the License is distributed on an "AS IS" BASIS,
  12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  13  * See the License for the specific language governing permissions and
  14  * limitations under the License.
  15  */
  16
  17 #ifndef RTNETLINK_H
  18 #define RTNETLINK_H 1
  19
  20 /* These functions are Linux specific, so they should be used directly only by
  21  * Linux-specific code. */
  22
  23 #include "list.h"
  24
  25 /* A digested version of an rtnetlink message sent down by the kernel to
  26  * indicate that a network device has been created or destroyed or changed.  */
  27 struct rtnetlink_change {
  28     /* Copied from struct nlmsghdr. */
  29     int nlmsg_type;             /* e.g. RTM_NEWLINK, RTM_DELLINK. */
  30
  31     /* Copied from struct ifinfomsg. */
  32     int ifi_index;              /* Index of network device. */
  33
  34     /* Extracted from Netlink attributes. */
  35     const char *ifname;         /* Name of network device. */
  36     int master_ifindex;         /* Ifindex of datapath master (0 if none). */
  37 };
  38
  39 /* Function called to report that a netdev has changed.  'change' describes the
  40  * specific change.  It may be null if the buffer of change information
  41  * overflowed, in which case the function must assume that every device may
  42  * have changed.  'aux' is as specified in the call to
  43  * rtnetlink_notifier_register().  */
  44 typedef void rtnetlink_notify_func(const struct rtnetlink_change *, void *aux);
  45
  46 struct rtnetlink_notifier {
  47     struct list node;
  48     rtnetlink_notify_func *cb;
  49     void *aux;
  50 };
  51
  52 int rtnetlink_notifier_register(struct rtnetlink_notifier *,
  53                                 rtnetlink_notify_func *, void *aux);
  54 void rtnetlink_notifier_unregister(struct rtnetlink_notifier *);
  55 void rtnetlink_notifier_run(void);
  56 void rtnetlink_notifier_wait(void);
  57
  58 #endif /* rtnetlink.h */