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<div class="title">ldns-mx.c</div> </div>
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<a href="ldns-mx_8c.html">Go to the documentation of this file.</a><div class="fragment"><pre class="fragment"><a name="l00001"></a>00001 <span class="comment">/*</span>
<a name="l00002"></a>00002 <span class="comment"> * mx is a small program that prints out the mx records</span>
<a name="l00003"></a>00003 <span class="comment"> * for a particular domain</span>
<a name="l00004"></a>00004 <span class="comment"> * (c) NLnet Labs, 2005 - 2008</span>
<a name="l00005"></a>00005 <span class="comment"> * See the file LICENSE for the license</span>
<a name="l00006"></a>00006 <span class="comment"> */</span>
<a name="l00007"></a>00007
<a name="l00008"></a>00008 <span class="preprocessor">#include "config.h"</span>
<a name="l00009"></a>00009
<a name="l00010"></a>00010 <span class="preprocessor">#include <<a class="code" href="ldns_8h.html" title="Including this file will include all ldns files, and define some lookup tables.">ldns/ldns.h</a>></span>
<a name="l00011"></a>00011
<a name="l00012"></a>00012 <span class="keyword">static</span> <span class="keywordtype">int</span>
<a name="l00013"></a>00013 usage(FILE *fp, <span class="keywordtype">char</span> *prog) {
<a name="l00014"></a>00014 fprintf(fp, <span class="stringliteral">"%s domain\n"</span>, prog);
<a name="l00015"></a>00015 fprintf(fp, <span class="stringliteral">" print out the mx for domain\n"</span>);
<a name="l00016"></a>00016 <span class="keywordflow">return</span> 0;
<a name="l00017"></a>00017 }
<a name="l00018"></a>00018
<a name="l00019"></a>00019 <span class="keywordtype">int</span>
<a name="l00020"></a><a class="code" href="ldns-mx_8c.html#a0ddf1224851353fc92bfbff6f499fa97">00020</a> <a class="code" href="linktest_8c.html#a840291bc02cba5474a4cb46a9b9566fe">main</a>(<span class="keywordtype">int</span> argc, <span class="keywordtype">char</span> *argv[])
<a name="l00021"></a>00021 {
<a name="l00022"></a>00022 <a class="code" href="structldns__struct__resolver.html" title="DNS stub resolver structure.">ldns_resolver</a> *res;
<a name="l00023"></a>00023 <a class="code" href="structldns__struct__rdf.html" title="Resource record data field.">ldns_rdf</a> *domain;
<a name="l00024"></a>00024 <a class="code" href="structldns__struct__pkt.html" title="DNS packet.">ldns_pkt</a> *p;
<a name="l00025"></a>00025 <a class="code" href="structldns__struct__rr__list.html" title="List or Set of Resource Records.">ldns_rr_list</a> *mx;
<a name="l00026"></a>00026 <a class="code" href="error_8h.html#aaa6d98f86f535cf87b83b89e91f488f9">ldns_status</a> s;
<a name="l00027"></a>00027
<a name="l00028"></a>00028 p = NULL;
<a name="l00029"></a>00029 mx = NULL;
<a name="l00030"></a>00030 domain = NULL;
<a name="l00031"></a>00031 res = NULL;
<a name="l00032"></a>00032
<a name="l00033"></a>00033 <span class="keywordflow">if</span> (argc != 2) {
<a name="l00034"></a>00034 usage(stdout, argv[0]);
<a name="l00035"></a>00035 exit(EXIT_FAILURE);
<a name="l00036"></a>00036 } <span class="keywordflow">else</span> {
<a name="l00037"></a>00037 <span class="comment">/* create a rdf from the command line arg */</span>
<a name="l00038"></a>00038 domain = <a class="code" href="dname_8c.html#af4963d4ae086b1d77a58c6f757a00462" title="creates a new dname rdf from a string.">ldns_dname_new_frm_str</a>(argv[1]);
<a name="l00039"></a>00039 <span class="keywordflow">if</span> (!domain) {
<a name="l00040"></a>00040 usage(stdout, argv[0]);
<a name="l00041"></a>00041 exit(EXIT_FAILURE);
<a name="l00042"></a>00042 }
<a name="l00043"></a>00043 }
<a name="l00044"></a>00044
<a name="l00045"></a>00045 <span class="comment">/* create a new resolver from /etc/resolv.conf */</span>
<a name="l00046"></a>00046 s = <a class="code" href="resolver_8c.html#a783fdb0e6523eb6c1f4a1563b32ac135" title="Configure a resolver by means of a resolv.conf file The file may be NULL in which case there will be ...">ldns_resolver_new_frm_file</a>(&res, NULL);
<a name="l00047"></a>00047
<a name="l00048"></a>00048 <span class="keywordflow">if</span> (s != <a class="code" href="error_8h.html#a11f34802bb1624af46054952e3b853afac58492ee3fc8d23f33c79824ed08c465">LDNS_STATUS_OK</a>) {
<a name="l00049"></a>00049 exit(EXIT_FAILURE);
<a name="l00050"></a>00050 }
<a name="l00051"></a>00051
<a name="l00052"></a>00052 <span class="comment">/* use the resolver to send a query for the mx </span>
<a name="l00053"></a>00053 <span class="comment"> * records of the domain given on the command line</span>
<a name="l00054"></a>00054 <span class="comment"> */</span>
<a name="l00055"></a>00055 p = <a class="code" href="resolver_8c.html#a11ed37ad2349dbdc0ce6fbb618091d10" title="Send a query to a nameserver.">ldns_resolver_query</a>(res,
<a name="l00056"></a>00056 domain,
<a name="l00057"></a>00057 <a class="code" href="rr_8h.html#a640100112b0009efe3d61bbf799b33daaf13c7ee3899f0484210333da33db2a6c" title="mail exchange">LDNS_RR_TYPE_MX</a>,
<a name="l00058"></a>00058 <a class="code" href="rr_8h.html#adc72070b39f210fae670577de8136600a2ad89c0befc939420e3b1157c07a8b46" title="the Internet">LDNS_RR_CLASS_IN</a>,
<a name="l00059"></a>00059 <a class="code" href="packet_8h.html#adbf4098a01ab543ebbcbd329103cc8d9">LDNS_RD</a>);
<a name="l00060"></a>00060
<a name="l00061"></a>00061 <a class="code" href="rdata_8c.html#a47cb2779f76f2f6561ff8ede8e41afec" title="frees a rdf structure _and_ frees the data.">ldns_rdf_deep_free</a>(domain);
<a name="l00062"></a>00062
<a name="l00063"></a>00063 <span class="keywordflow">if</span> (!p) {
<a name="l00064"></a>00064 exit(EXIT_FAILURE);
<a name="l00065"></a>00065 } <span class="keywordflow">else</span> {
<a name="l00066"></a>00066 <span class="comment">/* retrieve the MX records from the answer section of that</span>
<a name="l00067"></a>00067 <span class="comment"> * packet</span>
<a name="l00068"></a>00068 <span class="comment"> */</span>
<a name="l00069"></a>00069 mx = <a class="code" href="packet_8c.html#aff953969fdd5f6bbbae10569f3455505" title="return all the rr with a specific type from a packet.">ldns_pkt_rr_list_by_type</a>(p,
<a name="l00070"></a>00070 <a class="code" href="rr_8h.html#a640100112b0009efe3d61bbf799b33daaf13c7ee3899f0484210333da33db2a6c" title="mail exchange">LDNS_RR_TYPE_MX</a>,
<a name="l00071"></a>00071 <a class="code" href="packet_8h.html#adad42096a5200b78a988227bd8c59b71a80effb31e9d19e57c89b79424a0b08ec">LDNS_SECTION_ANSWER</a>);
<a name="l00072"></a>00072 <span class="keywordflow">if</span> (!mx) {
<a name="l00073"></a>00073 fprintf(stderr,
<a name="l00074"></a>00074 <span class="stringliteral">" *** invalid answer name %s after MX query for %s\n"</span>,
<a name="l00075"></a>00075 argv[1], argv[1]);
<a name="l00076"></a>00076 <a class="code" href="packet_8c.html#a05bd6d99b1f608238c67b84449724c16" title="frees the packet structure and all data that it contains.">ldns_pkt_free</a>(p);
<a name="l00077"></a>00077 <a class="code" href="resolver_8c.html#afddfa77c8dccef423178c340b9817401" title="Frees the allocated space for this resolver and all it's data.">ldns_resolver_deep_free</a>(res);
<a name="l00078"></a>00078 exit(EXIT_FAILURE);
<a name="l00079"></a>00079 } <span class="keywordflow">else</span> {
<a name="l00080"></a>00080 <a class="code" href="rr_8c.html#a59fd6b0801f57bd952d1c69386677095" title="sorts an rr_list (canonical wire format).">ldns_rr_list_sort</a>(mx);
<a name="l00081"></a>00081 <a class="code" href="host2str_8c.html#ac2840486d0b166f4af59360deb18600b" title="print a rr_list to output">ldns_rr_list_print</a>(stdout, mx);
<a name="l00082"></a>00082 <a class="code" href="rr_8c.html#a25181bd133a53f132abce4eefd8e33af" title="frees an rr_list structure and all rrs contained therein.">ldns_rr_list_deep_free</a>(mx);
<a name="l00083"></a>00083 }
<a name="l00084"></a>00084 }
<a name="l00085"></a>00085 <a class="code" href="packet_8c.html#a05bd6d99b1f608238c67b84449724c16" title="frees the packet structure and all data that it contains.">ldns_pkt_free</a>(p);
<a name="l00086"></a>00086 <a class="code" href="resolver_8c.html#afddfa77c8dccef423178c340b9817401" title="Frees the allocated space for this resolver and all it's data.">ldns_resolver_deep_free</a>(res);
<a name="l00087"></a>00087 <span class="keywordflow">return</span> 0;
<a name="l00088"></a>00088 }
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