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diff --git a/contrib/bind9/lib/lwres/man/lwres.html b/contrib/bind9/lib/lwres/man/lwres.html deleted file mode 100644 index 1d5e57bfd248f..0000000000000 --- a/contrib/bind9/lib/lwres/man/lwres.html +++ /dev/null @@ -1,216 +0,0 @@ -<!-- - - Copyright (C) 2004, 2005 Internet Systems Consortium, Inc. ("ISC") - - Copyright (C) 2000, 2001 Internet Software Consortium. - - - - Permission to use, copy, modify, and distribute this software for any - - purpose with or without fee is hereby granted, provided that the above - - copyright notice and this permission notice appear in all copies. - - - - THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH - - REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY - - AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT, - - INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM - - LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE - - OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR - - PERFORMANCE OF THIS SOFTWARE. ---> -<!-- $Id: lwres.html,v 1.4.2.1.4.9 2005/10/13 02:33:54 marka Exp $ --> -<html> -<head> -<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1"> -<title>lwres</title> -<meta name="generator" content="DocBook XSL Stylesheets V1.69.1"> -</head> -<body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"><div class="refentry" lang="en"> -<a name="id2463721"></a><div class="titlepage"></div> -<div class="refnamediv"> -<h2>Name</h2> -<p>lwres — introduction to the lightweight resolver library</p> -</div> -<div class="refsynopsisdiv"> -<h2>Synopsis</h2> -<div class="funcsynopsis"><pre class="funcsynopsisinfo">#include <lwres/lwres.h></pre></div> -</div> -<div class="refsect1" lang="en"> -<a name="id2525832"></a><h2>DESCRIPTION</h2> -<p> -The BIND 9 lightweight resolver library is a simple, name service -independent stub resolver library. It provides hostname-to-address -and address-to-hostname lookup services to applications by -transmitting lookup requests to a resolver daemon -<span><strong class="command">lwresd</strong></span> -running on the local host. The resover daemon performs the -lookup using the DNS or possibly other name service protocols, -and returns the results to the application through the library. -The library and resolver daemon communicate using a simple -UDP-based protocol. -</p> -</div> -<div class="refsect1" lang="en"> -<a name="id2525845"></a><h2>OVERVIEW</h2> -<p> -The lwresd library implements multiple name service APIs. -The standard -<code class="function">gethostbyname()</code>, -<code class="function">gethostbyaddr()</code>, -<code class="function">gethostbyname_r()</code>, -<code class="function">gethostbyaddr_r()</code>, -<code class="function">getaddrinfo()</code>, -<code class="function">getipnodebyname()</code>, -and -<code class="function">getipnodebyaddr()</code> -functions are all supported. To allow the lwres library to coexist -with system libraries that define functions of the same name, -the library defines these functions with names prefixed by -<code class="literal">lwres_</code>. -To define the standard names, applications must include the -header file -<code class="filename"><lwres/netdb.h></code> -which contains macro definitions mapping the standard function names -into -<code class="literal">lwres_</code> -prefixed ones. Operating system vendors who integrate the lwres -library into their base distributions should rename the functions -in the library proper so that the renaming macros are not needed. -</p> -<p> -The library also provides a native API consisting of the functions -<code class="function">lwres_getaddrsbyname()</code> -and -<code class="function">lwres_getnamebyaddr()</code>. -These may be called by applications that require more detailed -control over the lookup process than the standard functions -provide. -</p> -<p> -In addition to these name service independent address lookup -functions, the library implements a new, experimental API -for looking up arbitrary DNS resource records, using the -<code class="function">lwres_getaddrsbyname()</code> -function. -</p> -<p> -Finally, there is a low-level API for converting lookup -requests and responses to and from raw lwres protocol packets. -This API can be used by clients requiring nonblocking operation, -and is also used when implementing the server side of the lwres -protocol, for example in the -<span><strong class="command">lwresd</strong></span> -resolver daemon. The use of this low-level API in clients -and servers is outlined in the following sections. -</p> -</div> -<div class="refsect1" lang="en"> -<a name="id2525909"></a><h2>CLIENT-SIDE LOW-LEVEL API CALL FLOW</h2> -<p> -When a client program wishes to make an lwres request using the -native low-level API, it typically performs the following -sequence of actions. -</p> -<p> -(1) Allocate or use an existing <span class="type">lwres_packet_t</span>, -called <code class="varname">pkt</code> below. -</p> -<p> -(2) Set <em class="structfield"><code>pkt.recvlength</code></em> to the maximum length we will accept. -This is done so the receiver of our packets knows how large our receive -buffer is. The "default" is a constant in -<code class="filename">lwres.h</code>: <code class="constant">LWRES_RECVLENGTH = 4096</code>. -</p> -<p> -(3) Set <em class="structfield"><code>pkt.serial</code></em> -to a unique serial number. This value is echoed -back to the application by the remote server. -</p> -<p> -(4) Set <em class="structfield"><code>pkt.pktflags</code></em>. Usually this is set to 0. -</p> -<p> -(5) Set <em class="structfield"><code>pkt.result</code></em> to 0. -</p> -<p> -(6) Call <code class="function">lwres_*request_render()</code>, -or marshall in the data using the primitives -such as <code class="function">lwres_packet_render()</code> -and storing the packet data. -</p> -<p> -(7) Transmit the resulting buffer. -</p> -<p> -(8) Call <code class="function">lwres_*response_parse()</code> -to parse any packets received. -</p> -<p> -(9) Verify that the opcode and serial match a request, and process the -packet specific information contained in the body. -</p> -</div> -<div class="refsect1" lang="en"> -<a name="id2526056"></a><h2>SERVER-SIDE LOW-LEVEL API CALL FLOW</h2> -<p> -When implementing the server side of the lightweight resolver -protocol using the lwres library, a sequence of actions like the -following is typically involved in processing each request packet. -</p> -<p> -Note that the same <span class="type">lwres_packet_t</span> is used -in both the <code class="function">_parse()</code> and <code class="function">_render()</code> calls, -with only a few modifications made -to the packet header's contents between uses. This method is recommended -as it keeps the serial, opcode, and other fields correct. -</p> -<p> -(1) When a packet is received, call <code class="function">lwres_*request_parse()</code> to -unmarshall it. This returns a <span class="type">lwres_packet_t</span> (also called <code class="varname">pkt</code>, below) -as well as a data specific type, such as <span class="type">lwres_gabnrequest_t</span>. -</p> -<p> -(2) Process the request in the data specific type. -</p> -<p> -(3) Set the <em class="structfield"><code>pkt.result</code></em>, -<em class="structfield"><code>pkt.recvlength</code></em> as above. All other fields can -be left untouched since they were filled in by the <code class="function">*_parse()</code> call -above. If using <code class="function">lwres_*response_render()</code>, -<em class="structfield"><code>pkt.pktflags</code></em> will be set up -properly. Otherwise, the <code class="constant">LWRES_LWPACKETFLAG_RESPONSE</code> bit should be -set. -</p> -<p> -(4) Call the data specific rendering function, such as -<code class="function">lwres_gabnresponse_render()</code>. -</p> -<p> -(5) Send the resulting packet to the client. -</p> -<p> -</p> -</div> -<div class="refsect1" lang="en"> -<a name="id2526141"></a><h2>SEE ALSO</h2> -<p> -<span class="citerefentry"><span class="refentrytitle">lwres_gethostent</span>(3)</span>, - -<span class="citerefentry"><span class="refentrytitle">lwres_getipnode</span>(3)</span>, - -<span class="citerefentry"><span class="refentrytitle">lwres_getnameinfo</span>(3)</span>, - -<span class="citerefentry"><span class="refentrytitle">lwres_noop</span>(3)</span>, - -<span class="citerefentry"><span class="refentrytitle">lwres_gabn</span>(3)</span>, - -<span class="citerefentry"><span class="refentrytitle">lwres_gnba</span>(3)</span>, - -<span class="citerefentry"><span class="refentrytitle">lwres_context</span>(3)</span>, - -<span class="citerefentry"><span class="refentrytitle">lwres_config</span>(3)</span>, - -<span class="citerefentry"><span class="refentrytitle">resolver</span>(5)</span>, - -<span class="citerefentry"><span class="refentrytitle">lwresd</span>(8)</span>. - -</p> -</div> -</div></body> -</html> |