firmware-utils: move bcm_tag.h here
[openwrt/svn-archive/archive.git] / package / libnl-tiny / src / handlers.c
1 /*
2 * lib/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) 2003-2008 Thomas Graf <tgraf@suug.ch>
10 */
11
12 /**
13 * @ingroup core
14 * @defgroup cb Callbacks/Customization
15 *
16 * @details
17 * @par 1) Setting up a callback set
18 * @code
19 * // Allocate a callback set and initialize it to the verbose default set
20 * struct nl_cb *cb = nl_cb_alloc(NL_CB_VERBOSE);
21 *
22 * // Modify the set to call my_func() for all valid messages
23 * nl_cb_set(cb, NL_CB_VALID, NL_CB_CUSTOM, my_func, NULL);
24 *
25 * // Set the error message handler to the verbose default implementation
26 * // and direct it to print all errors to the given file descriptor.
27 * FILE *file = fopen(...);
28 * nl_cb_err(cb, NL_CB_VERBOSE, NULL, file);
29 * @endcode
30 * @{
31 */
32
33 #include <netlink-local.h>
34 #include <netlink/netlink.h>
35 #include <netlink/utils.h>
36 #include <netlink/msg.h>
37 #include <netlink/handlers.h>
38
39 /**
40 * @name Callback Handle Management
41 * @{
42 */
43
44 /**
45 * Allocate a new callback handle
46 * @arg kind callback kind to be used for initialization
47 * @return Newly allocated callback handle or NULL
48 */
49 struct nl_cb *nl_cb_alloc(enum nl_cb_kind kind)
50 {
51 int i;
52 struct nl_cb *cb;
53
54 if (kind < 0 || kind > NL_CB_KIND_MAX)
55 return NULL;
56
57 cb = calloc(1, sizeof(*cb));
58 if (!cb)
59 return NULL;
60
61 cb->cb_refcnt = 1;
62
63 for (i = 0; i <= NL_CB_TYPE_MAX; i++)
64 nl_cb_set(cb, i, kind, NULL, NULL);
65
66 nl_cb_err(cb, kind, NULL, NULL);
67
68 return cb;
69 }
70
71 /**
72 * Clone an existing callback handle
73 * @arg orig original callback handle
74 * @return Newly allocated callback handle being a duplicate of
75 * orig or NULL
76 */
77 struct nl_cb *nl_cb_clone(struct nl_cb *orig)
78 {
79 struct nl_cb *cb;
80
81 cb = nl_cb_alloc(NL_CB_DEFAULT);
82 if (!cb)
83 return NULL;
84
85 memcpy(cb, orig, sizeof(*orig));
86 cb->cb_refcnt = 1;
87
88 return cb;
89 }
90
91 void nl_cb_put(struct nl_cb *cb)
92 {
93 if (!cb)
94 return;
95
96 cb->cb_refcnt--;
97
98 if (cb->cb_refcnt < 0)
99 BUG();
100
101 if (cb->cb_refcnt <= 0)
102 free(cb);
103 }
104
105 /** @} */
106
107 /**
108 * @name Callback Setup
109 * @{
110 */
111
112 /**
113 * Set up a callback
114 * @arg cb callback set
115 * @arg type callback to modify
116 * @arg kind kind of implementation
117 * @arg func callback function (NL_CB_CUSTOM)
118 * @arg arg argument passed to callback
119 *
120 * @return 0 on success or a negative error code
121 */
122 int nl_cb_set(struct nl_cb *cb, enum nl_cb_type type, enum nl_cb_kind kind,
123 nl_recvmsg_msg_cb_t func, void *arg)
124 {
125 if (type < 0 || type > NL_CB_TYPE_MAX)
126 return -NLE_RANGE;
127
128 if (kind < 0 || kind > NL_CB_KIND_MAX)
129 return -NLE_RANGE;
130
131 if (kind == NL_CB_CUSTOM) {
132 cb->cb_set[type] = func;
133 cb->cb_args[type] = arg;
134 }
135
136 return 0;
137 }
138
139 /**
140 * Set up an error callback
141 * @arg cb callback set
142 * @arg kind kind of callback
143 * @arg func callback function
144 * @arg arg argument to be passed to callback function
145 */
146 int nl_cb_err(struct nl_cb *cb, enum nl_cb_kind kind,
147 nl_recvmsg_err_cb_t func, void *arg)
148 {
149 if (kind < 0 || kind > NL_CB_KIND_MAX)
150 return -NLE_RANGE;
151
152 if (kind == NL_CB_CUSTOM) {
153 cb->cb_err = func;
154 cb->cb_err_arg = arg;
155 }
156
157 return 0;
158 }
159
160 /** @} */
161
162 /** @} */