libnl  3.2.24-rc1
handlers.h
1 /*
2  * netlink/handlers.c default netlink message handlers
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 #ifndef NETLINK_HANDLERS_H_
13 #define NETLINK_HANDLERS_H_
14 
15 #include <stdio.h>
16 #include <stdint.h>
17 #include <sys/types.h>
18 #include <netlink/netlink-compat.h>
19 #include <netlink/netlink-kernel.h>
20 
21 #ifdef __cplusplus
22 extern "C" {
23 #endif
24 
25 struct nl_cb;
26 struct nl_sock;
27 struct nl_msg;
28 struct ucred;
29 
30 /**
31  * @name Callback Typedefs
32  * @{
33  */
34 
35 /**
36  * nl_recvmsgs() callback for message processing customization
37  * @ingroup cb
38  * @arg msg netlink message being processed
39  * @arg arg argument passwd on through caller
40  */
41 typedef int (*nl_recvmsg_msg_cb_t)(struct nl_msg *msg, void *arg);
42 
43 /**
44  * nl_recvmsgs() callback for error message processing customization
45  * @ingroup cb
46  * @arg nla netlink address of the peer
47  * @arg nlerr netlink error message being processed
48  * @arg arg argument passed on through caller
49  */
50 typedef int (*nl_recvmsg_err_cb_t)(struct sockaddr_nl *nla,
51  struct nlmsgerr *nlerr, void *arg);
52 
53 /** @} */
54 
55 /**
56  * Callback actions
57  * @ingroup cb
58  */
59 enum nl_cb_action {
60  /** Proceed with wathever would come next */
61  NL_OK,
62  /** Skip this message */
63  NL_SKIP,
64  /** Stop parsing altogether and discard remaining messages */
65  NL_STOP,
66 };
67 
68 /**
69  * Callback kinds
70  * @ingroup cb
71  */
72 enum nl_cb_kind {
73  /** Default handlers (quiet) */
74  NL_CB_DEFAULT,
75  /** Verbose default handlers (error messages printed) */
76  NL_CB_VERBOSE,
77  /** Debug handlers for debugging */
78  NL_CB_DEBUG,
79  /** Customized handler specified by the user */
80  NL_CB_CUSTOM,
81  __NL_CB_KIND_MAX,
82 };
83 
84 #define NL_CB_KIND_MAX (__NL_CB_KIND_MAX - 1)
85 
86 /**
87  * Callback types
88  * @ingroup cb
89  */
90 enum nl_cb_type {
91  /** Message is valid */
92  NL_CB_VALID,
93  /** Last message in a series of multi part messages received */
94  NL_CB_FINISH,
95  /** Report received that data was lost */
96  NL_CB_OVERRUN,
97  /** Message wants to be skipped */
98  NL_CB_SKIPPED,
99  /** Message is an acknowledge */
100  NL_CB_ACK,
101  /** Called for every message received */
102  NL_CB_MSG_IN,
103  /** Called for every message sent out except for nl_sendto() */
104  NL_CB_MSG_OUT,
105  /** Message is malformed and invalid */
106  NL_CB_INVALID,
107  /** Called instead of internal sequence number checking */
108  NL_CB_SEQ_CHECK,
109  /** Sending of an acknowledge message has been requested */
110  NL_CB_SEND_ACK,
111  /** Flag NLM_F_DUMP_INTR is set in message */
112  NL_CB_DUMP_INTR,
113  __NL_CB_TYPE_MAX,
114 };
115 
116 #define NL_CB_TYPE_MAX (__NL_CB_TYPE_MAX - 1)
117 
118 extern struct nl_cb * nl_cb_alloc(enum nl_cb_kind);
119 extern struct nl_cb * nl_cb_clone(struct nl_cb *);
120 extern struct nl_cb * nl_cb_get(struct nl_cb *);
121 extern void nl_cb_put(struct nl_cb *);
122 
123 extern int nl_cb_set(struct nl_cb *, enum nl_cb_type, enum nl_cb_kind,
124  nl_recvmsg_msg_cb_t, void *);
125 extern int nl_cb_set_all(struct nl_cb *, enum nl_cb_kind,
126  nl_recvmsg_msg_cb_t, void *);
127 extern int nl_cb_err(struct nl_cb *, enum nl_cb_kind, nl_recvmsg_err_cb_t,
128  void *);
129 
130 extern void nl_cb_overwrite_recvmsgs(struct nl_cb *,
131  int (*func)(struct nl_sock *,
132  struct nl_cb *));
133 extern void nl_cb_overwrite_recv(struct nl_cb *,
134  int (*func)(struct nl_sock *,
135  struct sockaddr_nl *,
136  unsigned char **,
137  struct ucred **));
138 extern void nl_cb_overwrite_send(struct nl_cb *,
139  int (*func)(struct nl_sock *,
140  struct nl_msg *));
141 
142 extern enum nl_cb_type nl_cb_active_type(struct nl_cb *cb);
143 
144 #ifdef __cplusplus
145 }
146 #endif
147 
148 #endif