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<h1>lib/cache_mngr.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/cache_mngr.c Cache Manager</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) 2003-2007 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 cache_mngt</span>
<a name="l00014"></a>00014 <span class="comment"> * @defgroup cache_mngr Manager</span>
<a name="l00015"></a>00015 <span class="comment"> * @brief Helps keeping caches up to date.</span>
<a name="l00016"></a>00016 <span class="comment"> *</span>
<a name="l00017"></a>00017 <span class="comment"> * The purpose of a cache manager is to keep track of caches and</span>
<a name="l00018"></a>00018 <span class="comment"> * automatically receive event notifications to keep the caches</span>
<a name="l00019"></a>00019 <span class="comment"> * up to date with the kernel state. Each manager has exactly one</span>
<a name="l00020"></a>00020 <span class="comment"> * netlink socket assigned which limits the scope of each manager</span>
<a name="l00021"></a>00021 <span class="comment"> * to exactly one netlink family. Therefore all caches committed</span>
<a name="l00022"></a>00022 <span class="comment"> * to a manager must be part of the same netlink family. Due to the</span>
<a name="l00023"></a>00023 <span class="comment"> * nature of a manager, it is not possible to have a cache maintain</span>
<a name="l00024"></a>00024 <span class="comment"> * two instances of the same cache type. The socket is subscribed</span>
<a name="l00025"></a>00025 <span class="comment"> * to the event notification group of each cache and also put into</span>
<a name="l00026"></a>00026 <span class="comment"> * non-blocking mode. Functions exist to poll() on the socket to</span>
<a name="l00027"></a>00027 <span class="comment"> * wait for new events to be received.</span>
<a name="l00028"></a>00028 <span class="comment"> *</span>
<a name="l00029"></a>00029 <span class="comment"> * @code</span>
<a name="l00030"></a>00030 <span class="comment"> * App libnl Kernel</span>
<a name="l00031"></a>00031 <span class="comment"> * | |</span>
<a name="l00032"></a>00032 <span class="comment"> * +-----------------+ [ notification, link change ]</span>
<a name="l00033"></a>00033 <span class="comment"> * | | Cache Manager | | [ (IFF_UP | IFF_RUNNING) ]</span>
<a name="l00034"></a>00034 <span class="comment"> * | | |</span>
<a name="l00035"></a>00035 <span class="comment"> * | | +------------+| | | [ notification, new addr ]</span>
<a name="l00036"></a>00036 <span class="comment"> * <-------|---| route/link |<-------(async)--+ [ 10.0.1.1/32 dev eth1 ]</span>
<a name="l00037"></a>00037 <span class="comment"> * | | +------------+| | |</span>
<a name="l00038"></a>00038 <span class="comment"> * | +------------+| |</span>
<a name="l00039"></a>00039 <span class="comment"> * <---|---|---| route/addr |<------|-(async)--------------+</span>
<a name="l00040"></a>00040 <span class="comment"> * | +------------+|</span>
<a name="l00041"></a>00041 <span class="comment"> * | | +------------+| |</span>
<a name="l00042"></a>00042 <span class="comment"> * <-------|---| ... ||</span>
<a name="l00043"></a>00043 <span class="comment"> * | | +------------+| |</span>
<a name="l00044"></a>00044 <span class="comment"> * +-----------------+</span>
<a name="l00045"></a>00045 <span class="comment"> * | |</span>
<a name="l00046"></a>00046 <span class="comment"> * @endcode</span>
<a name="l00047"></a>00047 <span class="comment"> *</span>
<a name="l00048"></a>00048 <span class="comment"> * @par 1) Creating a new cache manager</span>
<a name="l00049"></a>00049 <span class="comment"> * @code</span>
<a name="l00050"></a>00050 <span class="comment"> * struct nl_cache_mngr *mngr;</span>
<a name="l00051"></a>00051 <span class="comment"> *</span>
<a name="l00052"></a>00052 <span class="comment"> * // Allocate a new cache manager for RTNETLINK and automatically</span>
<a name="l00053"></a>00053 <span class="comment"> * // provide the caches added to the manager.</span>
<a name="l00054"></a>00054 <span class="comment"> * mngr = nl_cache_mngr_alloc(NETLINK_ROUTE, NL_AUTO_PROVIDE);</span>
<a name="l00055"></a>00055 <span class="comment"> * @endcode</span>
<a name="l00056"></a>00056 <span class="comment"> *</span>
<a name="l00057"></a>00057 <span class="comment"> * @par 2) Keep track of a cache</span>
<a name="l00058"></a>00058 <span class="comment"> * @code</span>
<a name="l00059"></a>00059 <span class="comment"> * struct nl_cache *cache;</span>
<a name="l00060"></a>00060 <span class="comment"> *</span>
<a name="l00061"></a>00061 <span class="comment"> * // Create a new cache for links/interfaces and ask the manager to</span>
<a name="l00062"></a>00062 <span class="comment"> * // keep it up to date for us. This will trigger a full dump request</span>
<a name="l00063"></a>00063 <span class="comment"> * // to initially fill the cache.</span>
<a name="l00064"></a>00064 <span class="comment"> * cache = nl_cache_mngr_add(mngr, "route/link");</span>
<a name="l00065"></a>00065 <span class="comment"> * @endcode</span>
<a name="l00066"></a>00066 <span class="comment"> *</span>
<a name="l00067"></a>00067 <span class="comment"> * @par 3) Make the manager receive updates</span>
<a name="l00068"></a>00068 <span class="comment"> * @code</span>
<a name="l00069"></a>00069 <span class="comment"> * // Give the manager the ability to receive updates, will call poll()</span>
<a name="l00070"></a>00070 <span class="comment"> * // with a timeout of 5 seconds.</span>
<a name="l00071"></a>00071 <span class="comment"> * if (nl_cache_mngr_poll(mngr, 5000) > 0) {</span>
<a name="l00072"></a>00072 <span class="comment"> * // Manager received at least one update, dump cache?</span>
<a name="l00073"></a>00073 <span class="comment"> * nl_cache_dump(cache, ...);</span>
<a name="l00074"></a>00074 <span class="comment"> * }</span>
<a name="l00075"></a>00075 <span class="comment"> * @endcode</span>
<a name="l00076"></a>00076 <span class="comment"> *</span>
<a name="l00077"></a>00077 <span class="comment"> * @par 4) Release cache manager</span>
<a name="l00078"></a>00078 <span class="comment"> * @code</span>
<a name="l00079"></a>00079 <span class="comment"> * nl_cache_mngr_free(mngr);</span>
<a name="l00080"></a>00080 <span class="comment"> * @endcode</span>
<a name="l00081"></a>00081 <span class="comment"> * @{</span>
<a name="l00082"></a>00082 <span class="comment"> */</span>
<a name="l00083"></a>00083
<a name="l00084"></a>00084 <span class="preprocessor">#include <netlink-local.h></span>
<a name="l00085"></a>00085 <span class="preprocessor">#include <netlink/netlink.h></span>
<a name="l00086"></a>00086 <span class="preprocessor">#include <netlink/cache.h></span>
<a name="l00087"></a>00087 <span class="preprocessor">#include <netlink/utils.h></span>
<a name="l00088"></a>00088
<a name="l00089"></a>00089 <span class="keyword">static</span> <span class="keywordtype">int</span> include_cb(<span class="keyword">struct</span> nl_object *obj, <span class="keyword">struct</span> <a class="code" href="structnl__parser__param.html">nl_parser_param</a> *p)
<a name="l00090"></a>00090 {
<a name="l00091"></a>00091 <span class="keyword">struct </span>nl_cache_assoc *ca = p->pp_arg;
<a name="l00092"></a>00092
<a name="l00093"></a>00093 NL_DBG(2, <span class="stringliteral">"Including object %p into cache %p\n"</span>, obj, ca->ca_cache);
<a name="l00094"></a>00094 <span class="preprocessor">#ifdef NL_DEBUG</span>
<a name="l00095"></a>00095 <span class="preprocessor"></span> <span class="keywordflow">if</span> (<a class="code" href="group__utils.html#ga2e170840b2132881f543285ea6323f52" title="Debug level.">nl_debug</a> >= 4)
<a name="l00096"></a>00096 <a class="code" href="group__object.html#ga22a8e9cfa628d4346de3655523fd90b3" title="Dump this object according to the specified parameters.">nl_object_dump</a>(obj, &nl_debug_dp);
<a name="l00097"></a>00097 <span class="preprocessor">#endif</span>
<a name="l00098"></a>00098 <span class="preprocessor"></span> <span class="keywordflow">return</span> nl_cache_include(ca->ca_cache, obj, ca->ca_change);
<a name="l00099"></a>00099 }
<a name="l00100"></a>00100
<a name="l00101"></a>00101 <span class="keyword">static</span> <span class="keywordtype">int</span> event_input(<span class="keyword">struct</span> nl_msg *msg, <span class="keywordtype">void</span> *arg)
<a name="l00102"></a>00102 {
<a name="l00103"></a>00103 <span class="keyword">struct </span>nl_cache_mngr *mngr = arg;
<a name="l00104"></a>00104 <span class="keywordtype">int</span> protocol = nlmsg_get_proto(msg);
<a name="l00105"></a>00105 <span class="keywordtype">int</span> type = <a class="code" href="group__msg.html#gaa5f29579d86d2bdab26c312b44b56de7" title="Return actual netlink message.">nlmsg_hdr</a>(msg)-><a class="code" href="structnlmsghdr.html#a7232c4e6cb513010e64887b7eebf8823" title="Message type (content type)">nlmsg_type</a>;
<a name="l00106"></a>00106 <span class="keyword">struct </span><a class="code" href="structnl__cache__ops.html" title="Cache Operations.">nl_cache_ops</a> *ops;
<a name="l00107"></a>00107 <span class="keywordtype">int</span> i, n;
<a name="l00108"></a>00108 <span class="keyword">struct </span><a class="code" href="structnl__parser__param.html">nl_parser_param</a> p = {
<a name="l00109"></a>00109 .pp_cb = include_cb,
<a name="l00110"></a>00110 };
<a name="l00111"></a>00111
<a name="l00112"></a>00112 NL_DBG(2, <span class="stringliteral">"Cache manager %p, handling new message %p as event\n"</span>,
<a name="l00113"></a>00113 mngr, msg);
<a name="l00114"></a>00114 <span class="preprocessor">#ifdef NL_DEBUG</span>
<a name="l00115"></a>00115 <span class="preprocessor"></span> <span class="keywordflow">if</span> (<a class="code" href="group__utils.html#ga2e170840b2132881f543285ea6323f52" title="Debug level.">nl_debug</a> >= 4)
<a name="l00116"></a>00116 <a class="code" href="group__msg.html#ga062de3af7d634b7638c053e4ba67a7eb" title="Dump message in human readable format to file descriptor.">nl_msg_dump</a>(msg, stderr);
<a name="l00117"></a>00117 <span class="preprocessor">#endif</span>
<a name="l00118"></a>00118 <span class="preprocessor"></span>
<a name="l00119"></a>00119 <span class="keywordflow">if</span> (mngr->cm_protocol != protocol)
<a name="l00120"></a>00120 BUG();
<a name="l00121"></a>00121
<a name="l00122"></a>00122 <span class="keywordflow">for</span> (i = 0; i < mngr->cm_nassocs; i++) {
<a name="l00123"></a>00123 <span class="keywordflow">if</span> (mngr->cm_assocs[i].ca_cache) {
<a name="l00124"></a>00124 ops = mngr->cm_assocs[i].ca_cache->c_ops;
<a name="l00125"></a>00125 <span class="keywordflow">for</span> (n = 0; ops->co_msgtypes[n].<a class="code" href="structnl__msgtype.html#a2b51527c3258ef4231b84d856a7c4164" title="Netlink message type.">mt_id</a> >= 0; n++)
<a name="l00126"></a>00126 <span class="keywordflow">if</span> (ops->co_msgtypes[n].<a class="code" href="structnl__msgtype.html#a2b51527c3258ef4231b84d856a7c4164" title="Netlink message type.">mt_id</a> == type)
<a name="l00127"></a>00127 <span class="keywordflow">goto</span> found;
<a name="l00128"></a>00128 }
<a name="l00129"></a>00129 }
<a name="l00130"></a>00130
<a name="l00131"></a>00131 <span class="keywordflow">return</span> <a class="code" href="group__cb.html#gga0c50cb29c507b3d7e8bc7d76c74675f8af77d78aac004c6d4bee57741d3a295ae" title="Skip this message.">NL_SKIP</a>;
<a name="l00132"></a>00132
<a name="l00133"></a>00133 found:
<a name="l00134"></a>00134 NL_DBG(2, <span class="stringliteral">"Associated message %p to cache %p\n"</span>,
<a name="l00135"></a>00135 msg, mngr->cm_assocs[i].ca_cache);
<a name="l00136"></a>00136 p.pp_arg = &mngr->cm_assocs[i];
<a name="l00137"></a>00137
<a name="l00138"></a>00138 <span class="keywordflow">return</span> nl_cache_parse(ops, NULL, <a class="code" href="group__msg.html#gaa5f29579d86d2bdab26c312b44b56de7" title="Return actual netlink message.">nlmsg_hdr</a>(msg), &p);
<a name="l00139"></a>00139 }
<a name="l00140"></a>00140 <span class="comment"></span>
<a name="l00141"></a>00141 <span class="comment">/**</span>
<a name="l00142"></a>00142 <span class="comment"> * Allocate new cache manager</span>
<a name="l00143"></a>00143 <span class="comment"> * @arg handle Netlink socket/handle to be used</span>
<a name="l00144"></a>00144 <span class="comment"> * @arg protocol Netlink Protocol this manager is used for</span>
<a name="l00145"></a>00145 <span class="comment"> * @arg flags Flags</span>
<a name="l00146"></a>00146 <span class="comment"> *</span>
<a name="l00147"></a>00147 <span class="comment"> * @return Newly allocated cache manager or NULL on failure.</span>
<a name="l00148"></a>00148 <span class="comment"> */</span>
<a name="l00149"></a><a class="code" href="group__cache__mngr.html#gacb350ed929ffe7d01fb8bc2f872b8b19">00149</a> <span class="keyword">struct </span>nl_cache_mngr *<a class="code" href="group__cache__mngr.html#gacb350ed929ffe7d01fb8bc2f872b8b19" title="Allocate new cache manager.">nl_cache_mngr_alloc</a>(<span class="keyword">struct</span> nl_handle *handle,
<a name="l00150"></a>00150 <span class="keywordtype">int</span> protocol, <span class="keywordtype">int</span> flags)
<a name="l00151"></a>00151 {
<a name="l00152"></a>00152 <span class="keyword">struct </span>nl_cache_mngr *mngr;
<a name="l00153"></a>00153
<a name="l00154"></a>00154 <span class="keywordflow">if</span> (handle == NULL)
<a name="l00155"></a>00155 BUG();
<a name="l00156"></a>00156
<a name="l00157"></a>00157 mngr = calloc(1, <span class="keyword">sizeof</span>(*mngr));
<a name="l00158"></a>00158 <span class="keywordflow">if</span> (!mngr)
<a name="l00159"></a>00159 <span class="keywordflow">goto</span> enomem;
<a name="l00160"></a>00160
<a name="l00161"></a>00161 mngr->cm_handle = handle;
<a name="l00162"></a>00162 mngr->cm_nassocs = 32;
<a name="l00163"></a>00163 mngr->cm_protocol = protocol;
<a name="l00164"></a>00164 mngr->cm_flags = flags;
<a name="l00165"></a>00165 mngr->cm_assocs = calloc(mngr->cm_nassocs,
<a name="l00166"></a>00166 <span class="keyword">sizeof</span>(<span class="keyword">struct</span> nl_cache_assoc));
<a name="l00167"></a>00167 <span class="keywordflow">if</span> (!mngr->cm_assocs)
<a name="l00168"></a>00168 <span class="keywordflow">goto</span> enomem;
<a name="l00169"></a>00169
<a name="l00170"></a>00170
<a name="l00171"></a>00171 <a class="code" href="group__socket.html#ga6ae4e46ad6ea991e92dd0cc2653ff371" title="Modify the callback handler associated to the socket.">nl_socket_modify_cb</a>(mngr->cm_handle, <a class="code" href="group__cb.html#gga3f60f4515ada826d2bf16395ee722363a6e1f371d16186a460f25ea9bb1306c47" title="Message is valid.">NL_CB_VALID</a>, <a class="code" href="group__cb.html#ggaba3fabad0c62db483941101e1a18d14da22448271a402b4c4a55733ef4884c038" title="Customized handler specified by the user.">NL_CB_CUSTOM</a>,
<a name="l00172"></a>00172 event_input, mngr);
<a name="l00173"></a>00173
<a name="l00174"></a>00174 <span class="comment">/* Required to receive async event notifications */</span>
<a name="l00175"></a>00175 <a class="code" href="group__socket.html#ga0ff2f43147e3a4547f7109578b3ca422" title="Disable sequence number checking.">nl_disable_sequence_check</a>(mngr->cm_handle);
<a name="l00176"></a>00176
<a name="l00177"></a>00177 <span class="keywordflow">if</span> (<a class="code" href="group__nl.html#ga68655d7fa8bd1944bec4761c95e576e9" title="Create and connect netlink socket.">nl_connect</a>(mngr->cm_handle, protocol) < 0)
<a name="l00178"></a>00178 <span class="keywordflow">goto</span> errout;
<a name="l00179"></a>00179
<a name="l00180"></a>00180 <span class="keywordflow">if</span> (<a class="code" href="group__socket.html#gafbf20258be9d18116a9179c76cdd2637" title="Set file descriptor of socket handle to non-blocking state.">nl_socket_set_nonblocking</a>(mngr->cm_handle) < 0)
<a name="l00181"></a>00181 <span class="keywordflow">goto</span> errout;
<a name="l00182"></a>00182
<a name="l00183"></a>00183 NL_DBG(1, <span class="stringliteral">"Allocated cache manager %p, protocol %d, %d caches\n"</span>,
<a name="l00184"></a>00184 mngr, protocol, mngr->cm_nassocs);
<a name="l00185"></a>00185
<a name="l00186"></a>00186 <span class="keywordflow">return</span> mngr;
<a name="l00187"></a>00187
<a name="l00188"></a>00188 enomem:
<a name="l00189"></a>00189 nl_errno(ENOMEM);
<a name="l00190"></a>00190 errout:
<a name="l00191"></a>00191 <a class="code" href="group__cache__mngr.html#ga3c3ff6903e0fd29c620cc9b7a47e5a99" title="Free cache manager.">nl_cache_mngr_free</a>(mngr);
<a name="l00192"></a>00192 <span class="keywordflow">return</span> NULL;
<a name="l00193"></a>00193 }
<a name="l00194"></a>00194 <span class="comment"></span>
<a name="l00195"></a>00195 <span class="comment">/**</span>
<a name="l00196"></a>00196 <span class="comment"> * Add cache responsibility to cache manager</span>
<a name="l00197"></a>00197 <span class="comment"> * @arg mngr Cache manager.</span>
<a name="l00198"></a>00198 <span class="comment"> * @arg name Name of cache to keep track of</span>
<a name="l00199"></a>00199 <span class="comment"> * @arg cb Function to be called upon changes.</span>
<a name="l00200"></a>00200 <span class="comment"> *</span>
<a name="l00201"></a>00201 <span class="comment"> * Allocates a new cache of the specified type and adds it to the manager.</span>
<a name="l00202"></a>00202 <span class="comment"> * The operation will trigger a full dump request from the kernel to</span>
<a name="l00203"></a>00203 <span class="comment"> * initially fill the contents of the cache. The manager will subscribe</span>
<a name="l00204"></a>00204 <span class="comment"> * to the notification group of the cache to keep track of any further</span>
<a name="l00205"></a>00205 <span class="comment"> * changes.</span>
<a name="l00206"></a>00206 <span class="comment"> *</span>
<a name="l00207"></a>00207 <span class="comment"> * @return The newly allocated cache or NULL on failure.</span>
<a name="l00208"></a>00208 <span class="comment"> */</span>
<a name="l00209"></a><a class="code" href="group__cache__mngr.html#ga68610a013ae88504ba9ff1dffb8464c0">00209</a> <span class="keyword">struct </span>nl_cache *<a class="code" href="group__cache__mngr.html#ga68610a013ae88504ba9ff1dffb8464c0" title="Add cache responsibility to cache manager.">nl_cache_mngr_add</a>(<span class="keyword">struct</span> nl_cache_mngr *mngr, <span class="keyword">const</span> <span class="keywordtype">char</span> *name,
<a name="l00210"></a>00210 change_func_t cb)
<a name="l00211"></a>00211 {
<a name="l00212"></a>00212 <span class="keyword">struct </span><a class="code" href="structnl__cache__ops.html" title="Cache Operations.">nl_cache_ops</a> *ops;
<a name="l00213"></a>00213 <span class="keyword">struct </span>nl_cache *cache;
<a name="l00214"></a>00214 <span class="keyword">struct </span><a class="code" href="structnl__af__group.html" title="Address family to netlink group association.">nl_af_group</a> *grp;
<a name="l00215"></a>00215 <span class="keywordtype">int</span> err, i;
<a name="l00216"></a>00216
<a name="l00217"></a>00217 ops = <a class="code" href="group__cache__mngt.html#ga7657cf661e569b4b43842a82e409b5fd" title="Lookup the set cache operations of a certain cache type.">nl_cache_ops_lookup</a>(name);
<a name="l00218"></a>00218 <span class="keywordflow">if</span> (!ops) {
<a name="l00219"></a>00219 nl_error(ENOENT, <span class="stringliteral">"Unknown cache type"</span>);
<a name="l00220"></a>00220 <span class="keywordflow">return</span> NULL;
<a name="l00221"></a>00221 }
<a name="l00222"></a>00222
<a name="l00223"></a>00223 <span class="keywordflow">if</span> (ops->co_protocol != mngr->cm_protocol) {
<a name="l00224"></a>00224 nl_error(EINVAL, <span class="stringliteral">"Netlink protocol mismatch"</span>);
<a name="l00225"></a>00225 <span class="keywordflow">return</span> NULL;
<a name="l00226"></a>00226 }
<a name="l00227"></a>00227
<a name="l00228"></a>00228 <span class="keywordflow">if</span> (ops->co_groups == NULL) {
<a name="l00229"></a>00229 nl_error(EOPNOTSUPP, NULL);
<a name="l00230"></a>00230 <span class="keywordflow">return</span> NULL;
<a name="l00231"></a>00231 }
<a name="l00232"></a>00232
<a name="l00233"></a>00233 <span class="keywordflow">for</span> (i = 0; i < mngr->cm_nassocs; i++) {
<a name="l00234"></a>00234 <span class="keywordflow">if</span> (mngr->cm_assocs[i].ca_cache &&
<a name="l00235"></a>00235 mngr->cm_assocs[i].ca_cache->c_ops == ops) {
<a name="l00236"></a>00236 nl_error(EEXIST, <span class="stringliteral">"Cache of this type already managed"</span>);
<a name="l00237"></a>00237 <span class="keywordflow">return</span> NULL;
<a name="l00238"></a>00238 }
<a name="l00239"></a>00239 }
<a name="l00240"></a>00240
<a name="l00241"></a>00241 retry:
<a name="l00242"></a>00242 <span class="keywordflow">for</span> (i = 0; i < mngr->cm_nassocs; i++)
<a name="l00243"></a>00243 <span class="keywordflow">if</span> (!mngr->cm_assocs[i].ca_cache)
<a name="l00244"></a>00244 <span class="keywordflow">break</span>;
<a name="l00245"></a>00245
<a name="l00246"></a>00246 <span class="keywordflow">if</span> (i >= mngr->cm_nassocs) {
<a name="l00247"></a>00247 mngr->cm_nassocs += 16;
<a name="l00248"></a>00248 mngr->cm_assocs = realloc(mngr->cm_assocs,
<a name="l00249"></a>00249 mngr->cm_nassocs *
<a name="l00250"></a>00250 <span class="keyword">sizeof</span>(<span class="keyword">struct</span> nl_cache_assoc));
<a name="l00251"></a>00251 <span class="keywordflow">if</span> (mngr->cm_assocs == NULL) {
<a name="l00252"></a>00252 nl_errno(ENOMEM);
<a name="l00253"></a>00253 <span class="keywordflow">return</span> NULL;
<a name="l00254"></a>00254 } <span class="keywordflow">else</span> {
<a name="l00255"></a>00255 NL_DBG(1, <span class="stringliteral">"Increased capacity of cache manager %p "</span> \
<a name="l00256"></a>00256 <span class="stringliteral">"to %d\n"</span>, mngr, mngr->cm_nassocs);
<a name="l00257"></a>00257 <span class="keywordflow">goto</span> retry;
<a name="l00258"></a>00258 }
<a name="l00259"></a>00259 }
<a name="l00260"></a>00260
<a name="l00261"></a>00261 cache = <a class="code" href="group__cache.html#ga9520ae0f2158db3c081f34c851d92252" title="Allocate an empty cache.">nl_cache_alloc</a>(ops);
<a name="l00262"></a>00262 <span class="keywordflow">if</span> (!cache) {
<a name="l00263"></a>00263 nl_errno(ENOMEM);
<a name="l00264"></a>00264 <span class="keywordflow">return</span> NULL;
<a name="l00265"></a>00265 }
<a name="l00266"></a>00266
<a name="l00267"></a>00267 <span class="keywordflow">for</span> (grp = ops->co_groups; grp-><a class="code" href="structnl__af__group.html#a8b51cf29b78960889696f161d5a852f8" title="Netlink group identifier.">ag_group</a>; grp++) {
<a name="l00268"></a>00268 err = <a class="code" href="group__socket.html#ga3d0fb09feebd7fe9d919437aef47239a" title="Join a group.">nl_socket_add_membership</a>(mngr->cm_handle, grp-><a class="code" href="structnl__af__group.html#a8b51cf29b78960889696f161d5a852f8" title="Netlink group identifier.">ag_group</a>);
<a name="l00269"></a>00269 <span class="keywordflow">if</span> (err < 0)
<a name="l00270"></a>00270 <span class="keywordflow">goto</span> errout_free_cache;
<a name="l00271"></a>00271 }
<a name="l00272"></a>00272
<a name="l00273"></a>00273 err = <a class="code" href="group__cache.html#gaf5bd584017847e6ef69ec36739a6aaf0" title="(Re)fill a cache with the contents in the kernel.">nl_cache_refill</a>(mngr->cm_handle, cache);
<a name="l00274"></a>00274 <span class="keywordflow">if</span> (err < 0)
<a name="l00275"></a>00275 <span class="keywordflow">goto</span> errout_drop_membership;
<a name="l00276"></a>00276
<a name="l00277"></a>00277 mngr->cm_assocs[i].ca_cache = cache;
<a name="l00278"></a>00278 mngr->cm_assocs[i].ca_change = cb;
<a name="l00279"></a>00279
<a name="l00280"></a>00280 <span class="keywordflow">if</span> (mngr->cm_flags & NL_AUTO_PROVIDE)
<a name="l00281"></a>00281 <a class="code" href="group__cache__mngt.html#ga6a5f7016b2aa9485979e2de38076014d" title="Provide a cache for global use.">nl_cache_mngt_provide</a>(cache);
<a name="l00282"></a>00282
<a name="l00283"></a>00283 NL_DBG(1, <span class="stringliteral">"Added cache %p <%s> to cache manager %p\n"</span>,
<a name="l00284"></a>00284 cache, nl_cache_name(cache), mngr);
<a name="l00285"></a>00285
<a name="l00286"></a>00286 <span class="keywordflow">return</span> cache;
<a name="l00287"></a>00287
<a name="l00288"></a>00288 errout_drop_membership:
<a name="l00289"></a>00289 <span class="keywordflow">for</span> (grp = ops->co_groups; grp-><a class="code" href="structnl__af__group.html#a8b51cf29b78960889696f161d5a852f8" title="Netlink group identifier.">ag_group</a>; grp++)
<a name="l00290"></a>00290 <a class="code" href="group__socket.html#ga0114b0736393662d10296a0480ebd49d" title="Leave a group.">nl_socket_drop_membership</a>(mngr->cm_handle, grp-><a class="code" href="structnl__af__group.html#a8b51cf29b78960889696f161d5a852f8" title="Netlink group identifier.">ag_group</a>);
<a name="l00291"></a>00291 errout_free_cache:
<a name="l00292"></a>00292 <a class="code" href="group__cache.html#ga530c896db26d72001d011114b1e6cfaa" title="Free a cache.">nl_cache_free</a>(cache);
<a name="l00293"></a>00293
<a name="l00294"></a>00294 <span class="keywordflow">return</span> NULL;
<a name="l00295"></a>00295 }
<a name="l00296"></a>00296 <span class="comment"></span>
<a name="l00297"></a>00297 <span class="comment">/**</span>
<a name="l00298"></a>00298 <span class="comment"> * Get file descriptor</span>
<a name="l00299"></a>00299 <span class="comment"> * @arg mngr Cache Manager</span>
<a name="l00300"></a>00300 <span class="comment"> *</span>
<a name="l00301"></a>00301 <span class="comment"> * Get the file descriptor of the socket associated to the manager.</span>
<a name="l00302"></a>00302 <span class="comment"> * This can be used to change socket options or monitor activity</span>
<a name="l00303"></a>00303 <span class="comment"> * using poll()/select().</span>
<a name="l00304"></a>00304 <span class="comment"> */</span>
<a name="l00305"></a><a class="code" href="group__cache__mngr.html#gac49581d90c6e7be9f3fa7fe009a88e80">00305</a> <span class="keywordtype">int</span> <a class="code" href="group__cache__mngr.html#gac49581d90c6e7be9f3fa7fe009a88e80" title="Get file descriptor.">nl_cache_mngr_get_fd</a>(<span class="keyword">struct</span> nl_cache_mngr *mngr)
<a name="l00306"></a>00306 {
<a name="l00307"></a>00307 <span class="keywordflow">return</span> nl_socket_get_fd(mngr->cm_handle);
<a name="l00308"></a>00308 }
<a name="l00309"></a>00309 <span class="comment"></span>
<a name="l00310"></a>00310 <span class="comment">/**</span>
<a name="l00311"></a>00311 <span class="comment"> * Check for event notifications</span>
<a name="l00312"></a>00312 <span class="comment"> * @arg mngr Cache Manager</span>
<a name="l00313"></a>00313 <span class="comment"> * @arg timeout Upper limit poll() will block, in milliseconds.</span>
<a name="l00314"></a>00314 <span class="comment"> *</span>
<a name="l00315"></a>00315 <span class="comment"> * Causes poll() to be called to check for new event notifications</span>
<a name="l00316"></a>00316 <span class="comment"> * being available. Automatically receives and handles available</span>
<a name="l00317"></a>00317 <span class="comment"> * notifications.</span>
<a name="l00318"></a>00318 <span class="comment"> *</span>
<a name="l00319"></a>00319 <span class="comment"> * This functionally is ideally called regularly during an idle</span>
<a name="l00320"></a>00320 <span class="comment"> * period.</span>
<a name="l00321"></a>00321 <span class="comment"> *</span>
<a name="l00322"></a>00322 <span class="comment"> * @return A positive value if at least one update was handled, 0</span>
<a name="l00323"></a>00323 <span class="comment"> * for none, or a negative error code.</span>
<a name="l00324"></a>00324 <span class="comment"> */</span>
<a name="l00325"></a><a class="code" href="group__cache__mngr.html#ga544e06be5c3cf48fa761677e152f64f6">00325</a> <span class="keywordtype">int</span> <a class="code" href="group__cache__mngr.html#ga544e06be5c3cf48fa761677e152f64f6" title="Check for event notifications.">nl_cache_mngr_poll</a>(<span class="keyword">struct</span> nl_cache_mngr *mngr, <span class="keywordtype">int</span> timeout)
<a name="l00326"></a>00326 {
<a name="l00327"></a>00327 <span class="keywordtype">int</span> ret;
<a name="l00328"></a>00328 <span class="keyword">struct </span>pollfd fds = {
<a name="l00329"></a>00329 .fd = nl_socket_get_fd(mngr->cm_handle),
<a name="l00330"></a>00330 .events = POLLIN,
<a name="l00331"></a>00331 };
<a name="l00332"></a>00332
<a name="l00333"></a>00333 NL_DBG(3, <span class="stringliteral">"Cache manager %p, poll() fd %d\n"</span>, mngr, fds.fd);
<a name="l00334"></a>00334 ret = poll(&fds, 1, timeout);
<a name="l00335"></a>00335 NL_DBG(3, <span class="stringliteral">"Cache manager %p, poll() returned %d\n"</span>, mngr, ret);
<a name="l00336"></a>00336 <span class="keywordflow">if</span> (ret < 0)
<a name="l00337"></a>00337 <span class="keywordflow">return</span> nl_errno(errno);
<a name="l00338"></a>00338
<a name="l00339"></a>00339 <span class="keywordflow">if</span> (ret == 0)
<a name="l00340"></a>00340 <span class="keywordflow">return</span> 0;
<a name="l00341"></a>00341
<a name="l00342"></a>00342 <span class="keywordflow">return</span> <a class="code" href="group__cache__mngr.html#gaea5a5c62599aefaf9a540f770a5b1fd4" title="Receive available event notifications.">nl_cache_mngr_data_ready</a>(mngr);
<a name="l00343"></a>00343 }
<a name="l00344"></a>00344 <span class="comment"></span>
<a name="l00345"></a>00345 <span class="comment">/**</span>
<a name="l00346"></a>00346 <span class="comment"> * Receive available event notifications</span>
<a name="l00347"></a>00347 <span class="comment"> * @arg mngr Cache manager</span>
<a name="l00348"></a>00348 <span class="comment"> *</span>
<a name="l00349"></a>00349 <span class="comment"> * This function can be called if the socket associated to the manager</span>
<a name="l00350"></a>00350 <span class="comment"> * contains updates to be received. This function should not be used</span>
<a name="l00351"></a>00351 <span class="comment"> * if nl_cache_mngr_poll() is used.</span>
<a name="l00352"></a>00352 <span class="comment"> *</span>
<a name="l00353"></a>00353 <span class="comment"> * @return A positive value if at least one update was handled, 0</span>
<a name="l00354"></a>00354 <span class="comment"> * for none, or a negative error code.</span>
<a name="l00355"></a>00355 <span class="comment"> */</span>
<a name="l00356"></a><a class="code" href="group__cache__mngr.html#gaea5a5c62599aefaf9a540f770a5b1fd4">00356</a> <span class="keywordtype">int</span> <a class="code" href="group__cache__mngr.html#gaea5a5c62599aefaf9a540f770a5b1fd4" title="Receive available event notifications.">nl_cache_mngr_data_ready</a>(<span class="keyword">struct</span> nl_cache_mngr *mngr)
<a name="l00357"></a>00357 {
<a name="l00358"></a>00358 <span class="keywordtype">int</span> err;
<a name="l00359"></a>00359
<a name="l00360"></a>00360 err = <a class="code" href="group__nl.html#gab287fc77c46d80c4e22bc87494cbf853" title="Receive a set of message from a netlink socket using handlers in nl_handle.">nl_recvmsgs_default</a>(mngr->cm_handle);
<a name="l00361"></a>00361 <span class="keywordflow">if</span> (err < 0)
<a name="l00362"></a>00362 <span class="keywordflow">return</span> err;
<a name="l00363"></a>00363
<a name="l00364"></a>00364 <span class="keywordflow">return</span> 1;
<a name="l00365"></a>00365 }
<a name="l00366"></a>00366 <span class="comment"></span>
<a name="l00367"></a>00367 <span class="comment">/**</span>
<a name="l00368"></a>00368 <span class="comment"> * Free cache manager</span>
<a name="l00369"></a>00369 <span class="comment"> * @arg mngr Cache manager</span>
<a name="l00370"></a>00370 <span class="comment"> *</span>
<a name="l00371"></a>00371 <span class="comment"> * Release all resources after usage of a cache manager.</span>
<a name="l00372"></a>00372 <span class="comment"> */</span>
<a name="l00373"></a><a class="code" href="group__cache__mngr.html#ga3c3ff6903e0fd29c620cc9b7a47e5a99">00373</a> <span class="keywordtype">void</span> <a class="code" href="group__cache__mngr.html#ga3c3ff6903e0fd29c620cc9b7a47e5a99" title="Free cache manager.">nl_cache_mngr_free</a>(<span class="keyword">struct</span> nl_cache_mngr *mngr)
<a name="l00374"></a>00374 {
<a name="l00375"></a>00375 <span class="keywordflow">if</span> (!mngr)
<a name="l00376"></a>00376 <span class="keywordflow">return</span>;
<a name="l00377"></a>00377
<a name="l00378"></a>00378 <span class="keywordflow">if</span> (mngr->cm_handle) {
<a name="l00379"></a>00379 <a class="code" href="group__nl.html#ga25039e93db5ab64ce4345ffe14379530" title="Close/Disconnect netlink socket.">nl_close</a>(mngr->cm_handle);
<a name="l00380"></a>00380 <a class="code" href="group__socket.html#gaf73c4d1d895ec4cd19f504aae96219b5" title="Destroy netlink handle.">nl_handle_destroy</a>(mngr->cm_handle);
<a name="l00381"></a>00381 }
<a name="l00382"></a>00382
<a name="l00383"></a>00383 free(mngr->cm_assocs);
<a name="l00384"></a>00384 free(mngr);
<a name="l00385"></a>00385
<a name="l00386"></a>00386 NL_DBG(1, <span class="stringliteral">"Cache manager %p freed\n"</span>, mngr);
<a name="l00387"></a>00387 }
<a name="l00388"></a>00388 <span class="comment"></span>
<a name="l00389"></a>00389 <span class="comment">/** @} */</span>
</pre></div></div>
</div>
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