package/libnl-tiny/src/include/netlink/socket.h

   1 /*
   2  * netlink/socket.h             Netlink Socket
   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) 2003-2008 Thomas Graf <tgraf@suug.ch>
  10  */
  11
  12 #ifndef NETLINK_SOCKET_H_
  13 #define NETLINK_SOCKET_H_
  14
  15 #include <netlink/types.h>
  16 #include <netlink/handlers.h>
  17
  18 #ifdef __cplusplus
  19 extern "C" {
  20 #endif
  21
  22 #define NL_SOCK_BUFSIZE_SET     (1<<0)
  23 #define NL_SOCK_PASSCRED        (1<<1)
  24 #define NL_OWN_PORT             (1<<2)
  25 #define NL_MSG_PEEK             (1<<3)
  26 #define NL_NO_AUTO_ACK          (1<<4)
  27
  28 struct nl_cb;
  29 struct nl_sock
  30 {
  31         struct sockaddr_nl      s_local;
  32         struct sockaddr_nl      s_peer;
  33         int                     s_fd;
  34         int                     s_proto;
  35         unsigned int            s_seq_next;
  36         unsigned int            s_seq_expect;
  37         int                     s_flags;
  38         struct nl_cb *          s_cb;
  39 };
  40
  41
  42 extern struct nl_sock * nl_socket_alloc(void);
  43 extern struct nl_sock * nl_socket_alloc_cb(struct nl_cb *);
  44 extern void             nl_socket_free(struct nl_sock *);
  45
  46 extern void             nl_socket_set_local_port(struct nl_sock *, uint32_t);
  47
  48 extern int              nl_socket_add_memberships(struct nl_sock *, int, ...);
  49 extern int              nl_socket_drop_memberships(struct nl_sock *, int, ...);
  50
  51 extern int              nl_socket_set_buffer_size(struct nl_sock *, int, int);
  52 extern int              nl_socket_set_passcred(struct nl_sock *, int);
  53 extern int              nl_socket_recv_pktinfo(struct nl_sock *, int);
  54
  55 extern void             nl_socket_disable_seq_check(struct nl_sock *);
  56
  57 extern int              nl_socket_set_nonblocking(struct nl_sock *);
  58
  59 /**
  60  * Use next sequence number
  61  * @arg sk              Netlink socket.
  62  *
  63  * Uses the next available sequence number and increases the counter
  64  * by one for subsequent calls.
  65  *
  66  * @return Unique serial sequence number
  67  */
  68 static inline unsigned int nl_socket_use_seq(struct nl_sock *sk)
  69 {
  70         return sk->s_seq_next++;
  71 }
  72
  73 /**
  74  * Disable automatic request for ACK
  75  * @arg sk              Netlink socket.
  76  *
  77  * The default behaviour of a socket is to request an ACK for
  78  * each message sent to allow for the caller to synchronize to
  79  * the completion of the netlink operation. This function
  80  * disables this behaviour and will result in requests being
  81  * sent which will not have the NLM_F_ACK flag set automatically.
  82  * However, it is still possible for the caller to set the
  83  * NLM_F_ACK flag explicitely.
  84  */
  85 static inline void nl_socket_disable_auto_ack(struct nl_sock *sk)
  86 {
  87         sk->s_flags |= NL_NO_AUTO_ACK;
  88 }
  89
  90 /**
  91  * Enable automatic request for ACK (default)
  92  * @arg sk              Netlink socket.
  93  * @see nl_socket_disable_auto_ack
  94  */
  95 static inline void nl_socket_enable_auto_ack(struct nl_sock *sk)
  96 {
  97         sk->s_flags &= ~NL_NO_AUTO_ACK;
  98 }
  99
 100 /**
 101  * @name Source Idenficiation
 102  * @{
 103  */
 104
 105 static inline uint32_t nl_socket_get_local_port(struct nl_sock *sk)
 106 {
 107         return sk->s_local.nl_pid;
 108 }
 109
 110 /**
 111  * Join multicast groups (deprecated)
 112  * @arg sk              Netlink socket.
 113  * @arg groups          Bitmask of groups to join.
 114  *
 115  * This function defines the old way of joining multicast group which
 116  * has to be done prior to calling nl_connect(). It works on any kernel
 117  * version but is very limited as only 32 groups can be joined.
 118  */
 119 static inline void nl_join_groups(struct nl_sock *sk, int groups)
 120 {
 121         sk->s_local.nl_groups |= groups;
 122 }
 123
 124 /**
 125  * @name Peer Identfication
 126  * @{
 127  */
 128
 129 static inline uint32_t nl_socket_get_peer_port(struct nl_sock *sk)
 130 {
 131         return sk->s_peer.nl_pid;
 132 }
 133
 134 static inline void nl_socket_set_peer_port(struct nl_sock *sk, uint32_t port)
 135 {
 136         sk->s_peer.nl_pid = port;
 137 }
 138
 139 /** @} */
 140
 141 /**
 142  * @name File Descriptor
 143  * @{
 144  */
 145
 146 static inline int nl_socket_get_fd(struct nl_sock *sk)
 147 {
 148         return sk->s_fd;
 149 }
 150
 151 /**
 152  * Enable use of MSG_PEEK when reading from socket
 153  * @arg sk              Netlink socket.
 154  */
 155 static inline void nl_socket_enable_msg_peek(struct nl_sock *sk)
 156 {
 157         sk->s_flags |= NL_MSG_PEEK;
 158 }
 159
 160 /**
 161  * Disable use of MSG_PEEK when reading from socket
 162  * @arg sk              Netlink socket.
 163  */
 164 static inline void nl_socket_disable_msg_peek(struct nl_sock *sk)
 165 {
 166         sk->s_flags &= ~NL_MSG_PEEK;
 167 }
 168
 169 /**
 170  * @name Callback Handler
 171  * @{
 172  */
 173
 174 static inline struct nl_cb *nl_socket_get_cb(struct nl_sock *sk)
 175 {
 176         return nl_cb_get(sk->s_cb);
 177 }
 178
 179 static inline void nl_socket_set_cb(struct nl_sock *sk, struct nl_cb *cb)
 180 {
 181         nl_cb_put(sk->s_cb);
 182         sk->s_cb = nl_cb_get(cb);
 183 }
 184
 185 /**
 186  * Modify the callback handler associated to the socket
 187  * @arg sk              Netlink socket.
 188  * @arg type            which type callback to set
 189  * @arg kind            kind of callback
 190  * @arg func            callback function
 191  * @arg arg             argument to be passwd to callback function
 192  *
 193  * @see nl_cb_set
 194  */
 195 static inline int nl_socket_modify_cb(struct nl_sock *sk, enum nl_cb_type type,
 196                         enum nl_cb_kind kind, nl_recvmsg_msg_cb_t func,
 197                         void *arg)
 198 {
 199         return nl_cb_set(sk->s_cb, type, kind, func, arg);
 200 }
 201
 202 /** @} */
 203
 204 static inline int nl_socket_add_membership(struct nl_sock *sk, int group)
 205 {
 206         return nl_socket_add_memberships(sk, group, 0);
 207 }
 208
 209
 210 static inline int nl_socket_drop_membership(struct nl_sock *sk, int group)
 211 {
 212         return nl_socket_drop_memberships(sk, group, 0);
 213 }
 214
 215
 216
 217 #ifdef __cplusplus
 218 }
 219 #endif
 220
 221 #endif