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<h1>lib/genl/genl.c</h1> </div>
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<div class="fragment"><pre class="fragment"><a name="l00001"></a>00001 <span class="comment">/*</span>
<a name="l00002"></a>00002 <span class="comment"> * lib/genl/genl.c Generic Netlink</span>
<a name="l00003"></a>00003 <span class="comment"> *</span>
<a name="l00004"></a>00004 <span class="comment"> * This library is free software; you can redistribute it and/or</span>
<a name="l00005"></a>00005 <span class="comment"> * modify it under the terms of the GNU Lesser General Public</span>
<a name="l00006"></a>00006 <span class="comment"> * License as published by the Free Software Foundation version 2.1</span>
<a name="l00007"></a>00007 <span class="comment"> * of the License.</span>
<a name="l00008"></a>00008 <span class="comment"> *</span>
<a name="l00009"></a>00009 <span class="comment"> * Copyright (c) 2003-2006 Thomas Graf <tgraf@suug.ch></span>
<a name="l00010"></a>00010 <span class="comment"> */</span>
<a name="l00011"></a>00011 <span class="comment"></span>
<a name="l00012"></a>00012 <span class="comment">/**</span>
<a name="l00013"></a>00013 <span class="comment"> * @ingroup nlfam</span>
<a name="l00014"></a>00014 <span class="comment"> * @defgroup genl Generic Netlink</span>
<a name="l00015"></a>00015 <span class="comment"> *</span>
<a name="l00016"></a>00016 <span class="comment"> * @par Message Format</span>
<a name="l00017"></a>00017 <span class="comment"> * @code</span>
<a name="l00018"></a>00018 <span class="comment"> * <------- NLMSG_ALIGN(hlen) ------> <---- NLMSG_ALIGN(len) ---></span>
<a name="l00019"></a>00019 <span class="comment"> * +----------------------------+- - -+- - - - - - - - - - -+- - -+</span>
<a name="l00020"></a>00020 <span class="comment"> * | Header | Pad | Payload | Pad |</span>
<a name="l00021"></a>00021 <span class="comment"> * | struct nlmsghdr | | | |</span>
<a name="l00022"></a>00022 <span class="comment"> * +----------------------------+- - -+- - - - - - - - - - -+- - -+</span>
<a name="l00023"></a>00023 <span class="comment"> * @endcode</span>
<a name="l00024"></a>00024 <span class="comment"> * @code</span>
<a name="l00025"></a>00025 <span class="comment"> * <-------- GENL_HDRLEN -------> <--- hdrlen --></span>
<a name="l00026"></a>00026 <span class="comment"> * <------- genlmsg_len(ghdr) ------></span>
<a name="l00027"></a>00027 <span class="comment"> * +------------------------+- - -+---------------+- - -+------------+</span>
<a name="l00028"></a>00028 <span class="comment"> * | Generic Netlink Header | Pad | Family Header | Pad | Attributes |</span>
<a name="l00029"></a>00029 <span class="comment"> * | struct genlmsghdr | | | | |</span>
<a name="l00030"></a>00030 <span class="comment"> * +------------------------+- - -+---------------+- - -+------------+</span>
<a name="l00031"></a>00031 <span class="comment"> * genlmsg_data(ghdr)--------------^ ^</span>
<a name="l00032"></a>00032 <span class="comment"> * genlmsg_attrdata(ghdr, hdrlen)-------------------------</span>
<a name="l00033"></a>00033 <span class="comment"> * @endcode</span>
<a name="l00034"></a>00034 <span class="comment"> *</span>
<a name="l00035"></a>00035 <span class="comment"> * @par Example</span>
<a name="l00036"></a>00036 <span class="comment"> * @code</span>
<a name="l00037"></a>00037 <span class="comment"> * #include <netlink/netlink.h></span>
<a name="l00038"></a>00038 <span class="comment"> * #include <netlink/genl/genl.h></span>
<a name="l00039"></a>00039 <span class="comment"> * #include <netlink/genl/ctrl.h></span>
<a name="l00040"></a>00040 <span class="comment"> *</span>
<a name="l00041"></a>00041 <span class="comment"> * struct nl_handle *sock;</span>
<a name="l00042"></a>00042 <span class="comment"> * struct nl_msg *msg;</span>
<a name="l00043"></a>00043 <span class="comment"> * int family;</span>
<a name="l00044"></a>00044 <span class="comment"> *</span>
<a name="l00045"></a>00045 <span class="comment"> * // Allocate a new netlink socket</span>
<a name="l00046"></a>00046 <span class="comment"> * sock = nl_handle_alloc();</span>
<a name="l00047"></a>00047 <span class="comment"> *</span>
<a name="l00048"></a>00048 <span class="comment"> * // Connect to generic netlink socket on kernel side</span>
<a name="l00049"></a>00049 <span class="comment"> * genl_connect(sock);</span>
<a name="l00050"></a>00050 <span class="comment"> *</span>
<a name="l00051"></a>00051 <span class="comment"> * // Ask kernel to resolve family name to family id</span>
<a name="l00052"></a>00052 <span class="comment"> * family = genl_ctrl_resolve(sock, "generic_netlink_family_name");</span>
<a name="l00053"></a>00053 <span class="comment"> *</span>
<a name="l00054"></a>00054 <span class="comment"> * // Construct a generic netlink by allocating a new message, fill in</span>
<a name="l00055"></a>00055 <span class="comment"> * // the header and append a simple integer attribute.</span>
<a name="l00056"></a>00056 <span class="comment"> * msg = nlmsg_alloc();</span>
<a name="l00057"></a>00057 <span class="comment"> * genlmsg_put(msg, NL_AUTO_PID, NL_AUTO_SEQ, family, 0, NLM_F_ECHO,</span>
<a name="l00058"></a>00058 <span class="comment"> * CMD_FOO_GET, FOO_VERSION);</span>
<a name="l00059"></a>00059 <span class="comment"> * nla_put_u32(msg, ATTR_FOO, 123);</span>
<a name="l00060"></a>00060 <span class="comment"> *</span>
<a name="l00061"></a>00061 <span class="comment"> * // Send message over netlink socket</span>
<a name="l00062"></a>00062 <span class="comment"> * nl_send_auto_complete(sock, msg);</span>
<a name="l00063"></a>00063 <span class="comment"> *</span>
<a name="l00064"></a>00064 <span class="comment"> * // Free message</span>
<a name="l00065"></a>00065 <span class="comment"> * nlmsg_free(msg);</span>
<a name="l00066"></a>00066 <span class="comment"> *</span>
<a name="l00067"></a>00067 <span class="comment"> * // Prepare socket to receive the answer by specifying the callback</span>
<a name="l00068"></a>00068 <span class="comment"> * // function to be called for valid messages.</span>
<a name="l00069"></a>00069 <span class="comment"> * nl_socket_modify_cb(sock, NL_CB_VALID, NL_CB_CUSTOM, parse_cb, NULL);</span>
<a name="l00070"></a>00070 <span class="comment"> *</span>
<a name="l00071"></a>00071 <span class="comment"> * // Wait for the answer and receive it</span>
<a name="l00072"></a>00072 <span class="comment"> * nl_recvmsgs_default(sock);</span>
<a name="l00073"></a>00073 <span class="comment"> *</span>
<a name="l00074"></a>00074 <span class="comment"> * static int parse_cb(struct nl_msg *msg, void *arg)</span>
<a name="l00075"></a>00075 <span class="comment"> * {</span>
<a name="l00076"></a>00076 <span class="comment"> * struct nlmsghdr *nlh = nlmsg_hdr(msg);</span>
<a name="l00077"></a>00077 <span class="comment"> * struct nlattr *attrs[ATTR_MAX+1];</span>
<a name="l00078"></a>00078 <span class="comment"> *</span>
<a name="l00079"></a>00079 <span class="comment"> * // Validate message and parse attributes</span>
<a name="l00080"></a>00080 <span class="comment"> * genlmsg_parse(nlh, 0, attrs, ATTR_MAX, policy);</span>
<a name="l00081"></a>00081 <span class="comment"> *</span>
<a name="l00082"></a>00082 <span class="comment"> * if (attrs[ATTR_FOO]) {</span>
<a name="l00083"></a>00083 <span class="comment"> * uint32_t value = nla_get_u32(attrs[ATTR_FOO]);</span>
<a name="l00084"></a>00084 <span class="comment"> * ...</span>
<a name="l00085"></a>00085 <span class="comment"> * }</span>
<a name="l00086"></a>00086 <span class="comment"> *</span>
<a name="l00087"></a>00087 <span class="comment"> * return 0;</span>
<a name="l00088"></a>00088 <span class="comment"> * }</span>
<a name="l00089"></a>00089 <span class="comment"> * @endcode</span>
<a name="l00090"></a>00090 <span class="comment"> * @{</span>
<a name="l00091"></a>00091 <span class="comment"> */</span>
<a name="l00092"></a>00092
<a name="l00093"></a>00093 <span class="preprocessor">#include <netlink-generic.h></span>
<a name="l00094"></a>00094 <span class="preprocessor">#include <netlink/netlink.h></span>
<a name="l00095"></a>00095 <span class="preprocessor">#include <netlink/genl/genl.h></span>
<a name="l00096"></a>00096 <span class="preprocessor">#include <netlink/utils.h></span>
<a name="l00097"></a>00097 <span class="comment"></span>
<a name="l00098"></a>00098 <span class="comment">/**</span>
<a name="l00099"></a>00099 <span class="comment"> * @name Socket Creating</span>
<a name="l00100"></a>00100 <span class="comment"> * @{</span>
<a name="l00101"></a>00101 <span class="comment"> */</span>
<a name="l00102"></a>00102
<a name="l00103"></a>00103 <span class="keywordtype">int</span> genl_connect(<span class="keyword">struct</span> nl_handle *handle)
<a name="l00104"></a>00104 {
<a name="l00105"></a>00105 <span class="keywordflow">return</span> <a class="code" href="group__nl.html#ga68655d7fa8bd1944bec4761c95e576e9" title="Create and connect netlink socket.">nl_connect</a>(handle, NETLINK_GENERIC);
<a name="l00106"></a>00106 }
<a name="l00107"></a>00107 <span class="comment"></span>
<a name="l00108"></a>00108 <span class="comment">/** @} */</span>
<a name="l00109"></a>00109 <span class="comment"></span>
<a name="l00110"></a>00110 <span class="comment">/**</span>
<a name="l00111"></a>00111 <span class="comment"> * @name Sending</span>
<a name="l00112"></a>00112 <span class="comment"> * @{</span>
<a name="l00113"></a>00113 <span class="comment"> */</span>
<a name="l00114"></a>00114 <span class="comment"></span>
<a name="l00115"></a>00115 <span class="comment">/**</span>
<a name="l00116"></a>00116 <span class="comment"> * Send trivial generic netlink message</span>
<a name="l00117"></a>00117 <span class="comment"> * @arg handle Netlink handle.</span>
<a name="l00118"></a>00118 <span class="comment"> * @arg family Generic netlink family</span>
<a name="l00119"></a>00119 <span class="comment"> * @arg cmd Command</span>
<a name="l00120"></a>00120 <span class="comment"> * @arg version Version</span>
<a name="l00121"></a>00121 <span class="comment"> * @arg flags Additional netlink message flags.</span>
<a name="l00122"></a>00122 <span class="comment"> *</span>
<a name="l00123"></a>00123 <span class="comment"> * Fills out a routing netlink request message and sends it out</span>
<a name="l00124"></a>00124 <span class="comment"> * using nl_send_simple().</span>
<a name="l00125"></a>00125 <span class="comment"> *</span>
<a name="l00126"></a>00126 <span class="comment"> * @return 0 on success or a negative error code.</span>
<a name="l00127"></a>00127 <span class="comment"> */</span>
<a name="l00128"></a><a class="code" href="group__genl.html#ga3454e19240e23a023ea469f780d9899d">00128</a> <span class="keywordtype">int</span> <a class="code" href="group__genl.html#ga3454e19240e23a023ea469f780d9899d" title="Send trivial generic netlink message.">genl_send_simple</a>(<span class="keyword">struct</span> nl_handle *handle, <span class="keywordtype">int</span> family, <span class="keywordtype">int</span> cmd,
<a name="l00129"></a>00129 <span class="keywordtype">int</span> version, <span class="keywordtype">int</span> flags)
<a name="l00130"></a>00130 {
<a name="l00131"></a>00131 <span class="keyword">struct </span>genlmsghdr hdr = {
<a name="l00132"></a>00132 .cmd = cmd,
<a name="l00133"></a>00133 .version = version,
<a name="l00134"></a>00134 };
<a name="l00135"></a>00135
<a name="l00136"></a>00136 <span class="keywordflow">return</span> <a class="code" href="group__nl.html#ga73ed88a505f2d67bcf328183fe1e692a" title="Send simple netlink message using nl_send_auto_complete()">nl_send_simple</a>(handle, family, flags, &hdr, <span class="keyword">sizeof</span>(hdr));
<a name="l00137"></a>00137 }
<a name="l00138"></a>00138 <span class="comment"></span>
<a name="l00139"></a>00139 <span class="comment">/** @} */</span>
<a name="l00140"></a>00140
<a name="l00141"></a>00141 <span class="comment"></span>
<a name="l00142"></a>00142 <span class="comment">/**</span>
<a name="l00143"></a>00143 <span class="comment"> * @name Message Parsing</span>
<a name="l00144"></a>00144 <span class="comment"> * @{</span>
<a name="l00145"></a>00145 <span class="comment"> */</span>
<a name="l00146"></a>00146
<a name="l00147"></a>00147 <span class="keywordtype">int</span> genlmsg_valid_hdr(<span class="keyword">struct</span> <a class="code" href="structnlmsghdr.html" title="Netlink message header.">nlmsghdr</a> *nlh, <span class="keywordtype">int</span> hdrlen)
<a name="l00148"></a>00148 {
<a name="l00149"></a>00149 <span class="keyword">struct </span>genlmsghdr *ghdr;
<a name="l00150"></a>00150
<a name="l00151"></a>00151 <span class="keywordflow">if</span> (!nlmsg_valid_hdr(nlh, GENL_HDRLEN))
<a name="l00152"></a>00152 <span class="keywordflow">return</span> 0;
<a name="l00153"></a>00153
<a name="l00154"></a>00154 ghdr = <a class="code" href="group__msg.html#gae44a904bb40c8b5f5ff31539c21cfa5a" title="head of message payload">nlmsg_data</a>(nlh);
<a name="l00155"></a>00155 <span class="keywordflow">if</span> (<a class="code" href="group__genl.html#ga33ac98a8facab52d3cfd3382ef5b1289" title="Get lenght of message payload.">genlmsg_len</a>(ghdr) < NLMSG_ALIGN(hdrlen))
<a name="l00156"></a>00156 <span class="keywordflow">return</span> 0;
<a name="l00157"></a>00157
<a name="l00158"></a>00158 <span class="keywordflow">return</span> 1;
<a name="l00159"></a>00159 }
<a name="l00160"></a>00160
<a name="l00161"></a>00161 <span class="keywordtype">int</span> genlmsg_validate(<span class="keyword">struct</span> <a class="code" href="structnlmsghdr.html" title="Netlink message header.">nlmsghdr</a> *nlh, <span class="keywordtype">int</span> hdrlen, <span class="keywordtype">int</span> maxtype,
<a name="l00162"></a>00162 <span class="keyword">struct</span> <a class="code" href="structnla__policy.html" title="attribute validation policy">nla_policy</a> *policy)
<a name="l00163"></a>00163 {
<a name="l00164"></a>00164 <span class="keyword">struct </span>genlmsghdr *ghdr;
<a name="l00165"></a>00165
<a name="l00166"></a>00166 <span class="keywordflow">if</span> (!genlmsg_valid_hdr(nlh, hdrlen))
<a name="l00167"></a>00167 <span class="keywordflow">return</span> nl_errno(EINVAL);
<a name="l00168"></a>00168
<a name="l00169"></a>00169 ghdr = <a class="code" href="group__msg.html#gae44a904bb40c8b5f5ff31539c21cfa5a" title="head of message payload">nlmsg_data</a>(nlh);
<a name="l00170"></a>00170 <span class="keywordflow">return</span> <a class="code" href="group__attr.html#ga5d8d5930b012e61c8d8e4ba6b3038c36" title="Validate a stream of attributes.">nla_validate</a>(<a class="code" href="group__genl.html#ga800671a530b4c7a6fca7b5b43c8ca5aa" title="Get head of attribute data.">genlmsg_attrdata</a>(ghdr, hdrlen),
<a name="l00171"></a>00171 <a class="code" href="group__genl.html#gabdae2ebb53a8c98adb2446d33c74e1e5" title="Get length of attribute data.">genlmsg_attrlen</a>(ghdr, hdrlen), maxtype, policy);
<a name="l00172"></a>00172 }
<a name="l00173"></a>00173
<a name="l00174"></a>00174 <span class="keywordtype">int</span> genlmsg_parse(<span class="keyword">struct</span> <a class="code" href="structnlmsghdr.html" title="Netlink message header.">nlmsghdr</a> *nlh, <span class="keywordtype">int</span> hdrlen, <span class="keyword">struct</span> nlattr *tb[],
<a name="l00175"></a>00175 <span class="keywordtype">int</span> maxtype, <span class="keyword">struct</span> <a class="code" href="structnla__policy.html" title="attribute validation policy">nla_policy</a> *policy)
<a name="l00176"></a>00176 {
<a name="l00177"></a>00177 <span class="keyword">struct </span>genlmsghdr *ghdr;
<a name="l00178"></a>00178
<a name="l00179"></a>00179 <span class="keywordflow">if</span> (!genlmsg_valid_hdr(nlh, hdrlen))
<a name="l00180"></a>00180 <span class="keywordflow">return</span> nl_errno(EINVAL);
<a name="l00181"></a>00181
<a name="l00182"></a>00182 ghdr = <a class="code" href="group__msg.html#gae44a904bb40c8b5f5ff31539c21cfa5a" title="head of message payload">nlmsg_data</a>(nlh);
<a name="l00183"></a>00183 <span class="keywordflow">return</span> <a class="code" href="group__attr.html#gaa7ad544b5a93034602a442eb26cda92c" title="Parse a stream of attributes into a tb buffer.">nla_parse</a>(tb, maxtype, <a class="code" href="group__genl.html#ga800671a530b4c7a6fca7b5b43c8ca5aa" title="Get head of attribute data.">genlmsg_attrdata</a>(ghdr, hdrlen),
<a name="l00184"></a>00184 <a class="code" href="group__genl.html#gabdae2ebb53a8c98adb2446d33c74e1e5" title="Get length of attribute data.">genlmsg_attrlen</a>(ghdr, hdrlen), policy);
<a name="l00185"></a>00185 }
<a name="l00186"></a>00186 <span class="comment"></span>
<a name="l00187"></a>00187 <span class="comment">/**</span>
<a name="l00188"></a>00188 <span class="comment"> * Get head of message payload</span>
<a name="l00189"></a>00189 <span class="comment"> * @arg gnlh genetlink messsage header</span>
<a name="l00190"></a>00190 <span class="comment"> */</span>
<a name="l00191"></a><a class="code" href="group__genl.html#ga8924deee081eaae1011d5b5ecc497478">00191</a> <span class="keywordtype">void</span> *<a class="code" href="group__genl.html#ga8924deee081eaae1011d5b5ecc497478" title="Get head of message payload.">genlmsg_data</a>(<span class="keyword">const</span> <span class="keyword">struct</span> genlmsghdr *gnlh)
<a name="l00192"></a>00192 {
<a name="l00193"></a>00193 <span class="keywordflow">return</span> ((<span class="keywordtype">unsigned</span> <span class="keywordtype">char</span> *) gnlh + GENL_HDRLEN);
<a name="l00194"></a>00194 }
<a name="l00195"></a>00195 <span class="comment"></span>
<a name="l00196"></a>00196 <span class="comment">/**</span>
<a name="l00197"></a>00197 <span class="comment"> * Get lenght of message payload</span>
<a name="l00198"></a>00198 <span class="comment"> * @arg gnlh genetlink message header</span>
<a name="l00199"></a>00199 <span class="comment"> */</span>
<a name="l00200"></a><a class="code" href="group__genl.html#ga33ac98a8facab52d3cfd3382ef5b1289">00200</a> <span class="keywordtype">int</span> <a class="code" href="group__genl.html#ga33ac98a8facab52d3cfd3382ef5b1289" title="Get lenght of message payload.">genlmsg_len</a>(<span class="keyword">const</span> <span class="keyword">struct</span> genlmsghdr *gnlh)
<a name="l00201"></a>00201 {
<a name="l00202"></a>00202 <span class="keyword">struct </span><a class="code" href="structnlmsghdr.html" title="Netlink message header.">nlmsghdr</a> *nlh = (<span class="keyword">struct </span><a class="code" href="structnlmsghdr.html" title="Netlink message header.">nlmsghdr</a> *)((<span class="keywordtype">unsigned</span> <span class="keywordtype">char</span> *)gnlh -
<a name="l00203"></a>00203 NLMSG_HDRLEN);
<a name="l00204"></a>00204 <span class="keywordflow">return</span> (nlh-><a class="code" href="structnlmsghdr.html#a5a3fdb3436743ec73e75471c899fd4bc" title="Length of message including header.">nlmsg_len</a> - GENL_HDRLEN - NLMSG_HDRLEN);
<a name="l00205"></a>00205 }
<a name="l00206"></a>00206 <span class="comment"></span>
<a name="l00207"></a>00207 <span class="comment">/**</span>
<a name="l00208"></a>00208 <span class="comment"> * Get head of attribute data</span>
<a name="l00209"></a>00209 <span class="comment"> * @arg gnlh generic netlink message header</span>
<a name="l00210"></a>00210 <span class="comment"> * @arg hdrlen length of family specific header</span>
<a name="l00211"></a>00211 <span class="comment"> */</span>
<a name="l00212"></a><a class="code" href="group__genl.html#ga800671a530b4c7a6fca7b5b43c8ca5aa">00212</a> <span class="keyword">struct </span>nlattr *<a class="code" href="group__genl.html#ga800671a530b4c7a6fca7b5b43c8ca5aa" title="Get head of attribute data.">genlmsg_attrdata</a>(<span class="keyword">const</span> <span class="keyword">struct</span> genlmsghdr *gnlh, <span class="keywordtype">int</span> hdrlen)
<a name="l00213"></a>00213 {
<a name="l00214"></a>00214 <span class="keywordflow">return</span> <a class="code" href="group__genl.html#ga8924deee081eaae1011d5b5ecc497478" title="Get head of message payload.">genlmsg_data</a>(gnlh) + NLMSG_ALIGN(hdrlen);
<a name="l00215"></a>00215 }
<a name="l00216"></a>00216 <span class="comment"></span>
<a name="l00217"></a>00217 <span class="comment">/**</span>
<a name="l00218"></a>00218 <span class="comment"> * Get length of attribute data</span>
<a name="l00219"></a>00219 <span class="comment"> * @arg gnlh generic netlink message header</span>
<a name="l00220"></a>00220 <span class="comment"> * @arg hdrlen length of family specific header</span>
<a name="l00221"></a>00221 <span class="comment"> */</span>
<a name="l00222"></a><a class="code" href="group__genl.html#gabdae2ebb53a8c98adb2446d33c74e1e5">00222</a> <span class="keywordtype">int</span> <a class="code" href="group__genl.html#gabdae2ebb53a8c98adb2446d33c74e1e5" title="Get length of attribute data.">genlmsg_attrlen</a>(<span class="keyword">const</span> <span class="keyword">struct</span> genlmsghdr *gnlh, <span class="keywordtype">int</span> hdrlen)
<a name="l00223"></a>00223 {
<a name="l00224"></a>00224 <span class="keywordflow">return</span> <a class="code" href="group__genl.html#ga33ac98a8facab52d3cfd3382ef5b1289" title="Get lenght of message payload.">genlmsg_len</a>(gnlh) - NLMSG_ALIGN(hdrlen);
<a name="l00225"></a>00225 }
<a name="l00226"></a>00226 <span class="comment"></span>
<a name="l00227"></a>00227 <span class="comment">/** @} */</span>
<a name="l00228"></a>00228 <span class="comment"></span>
<a name="l00229"></a>00229 <span class="comment">/**</span>
<a name="l00230"></a>00230 <span class="comment"> * @name Message Building</span>
<a name="l00231"></a>00231 <span class="comment"> * @{</span>
<a name="l00232"></a>00232 <span class="comment"> */</span>
<a name="l00233"></a>00233 <span class="comment"></span>
<a name="l00234"></a>00234 <span class="comment">/**</span>
<a name="l00235"></a>00235 <span class="comment"> * Add generic netlink header to netlink message</span>
<a name="l00236"></a>00236 <span class="comment"> * @arg msg netlink message</span>
<a name="l00237"></a>00237 <span class="comment"> * @arg pid netlink process id or NL_AUTO_PID</span>
<a name="l00238"></a>00238 <span class="comment"> * @arg seq sequence number of message or NL_AUTO_SEQ</span>
<a name="l00239"></a>00239 <span class="comment"> * @arg family generic netlink family</span>
<a name="l00240"></a>00240 <span class="comment"> * @arg hdrlen length of user specific header</span>
<a name="l00241"></a>00241 <span class="comment"> * @arg flags message flags</span>
<a name="l00242"></a>00242 <span class="comment"> * @arg cmd generic netlink command</span>
<a name="l00243"></a>00243 <span class="comment"> * @arg version protocol version</span>
<a name="l00244"></a>00244 <span class="comment"> *</span>
<a name="l00245"></a>00245 <span class="comment"> * Returns pointer to user specific header.</span>
<a name="l00246"></a>00246 <span class="comment"> */</span>
<a name="l00247"></a><a class="code" href="group__genl.html#ga59cab79b0fb5c86a041b0220461d78dd">00247</a> <span class="keywordtype">void</span> *<a class="code" href="group__genl.html#ga59cab79b0fb5c86a041b0220461d78dd" title="Add generic netlink header to netlink message.">genlmsg_put</a>(<span class="keyword">struct</span> nl_msg *msg, uint32_t pid, uint32_t seq, <span class="keywordtype">int</span> family,
<a name="l00248"></a>00248 <span class="keywordtype">int</span> hdrlen, <span class="keywordtype">int</span> flags, uint8_t cmd, uint8_t version)
<a name="l00249"></a>00249 {
<a name="l00250"></a>00250 <span class="keyword">struct </span><a class="code" href="structnlmsghdr.html" title="Netlink message header.">nlmsghdr</a> *nlh;
<a name="l00251"></a>00251 <span class="keyword">struct </span>genlmsghdr hdr = {
<a name="l00252"></a>00252 .cmd = cmd,
<a name="l00253"></a>00253 .version = version,
<a name="l00254"></a>00254 };
<a name="l00255"></a>00255
<a name="l00256"></a>00256 nlh = <a class="code" href="group__msg.html#ga16919a9a8579f8b538b0376781c1839d" title="Add a netlink message header to a netlink message.">nlmsg_put</a>(msg, pid, seq, family, GENL_HDRLEN + hdrlen, flags);
<a name="l00257"></a>00257 <span class="keywordflow">if</span> (nlh == NULL)
<a name="l00258"></a>00258 <span class="keywordflow">return</span> NULL;
<a name="l00259"></a>00259
<a name="l00260"></a>00260 memcpy(<a class="code" href="group__msg.html#gae44a904bb40c8b5f5ff31539c21cfa5a" title="head of message payload">nlmsg_data</a>(nlh), &hdr, <span class="keyword">sizeof</span>(hdr));
<a name="l00261"></a>00261 NL_DBG(2, <span class="stringliteral">"msg %p: Added generic netlink header cmd=%d version=%d\n"</span>,
<a name="l00262"></a>00262 msg, cmd, version);
<a name="l00263"></a>00263
<a name="l00264"></a>00264 <span class="keywordflow">return</span> <a class="code" href="group__msg.html#gae44a904bb40c8b5f5ff31539c21cfa5a" title="head of message payload">nlmsg_data</a>(nlh) + GENL_HDRLEN;
<a name="l00265"></a>00265 }
<a name="l00266"></a>00266 <span class="comment"></span>
<a name="l00267"></a>00267 <span class="comment">/** @} */</span>
<a name="l00268"></a>00268 <span class="comment"></span>
<a name="l00269"></a>00269 <span class="comment">/** @} */</span>
</pre></div></div>
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