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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 e4bbc098fa16..000000000000 --- a/contrib/bind9/lib/lwres/man/lwres.html +++ /dev/null @@ -1,218 +0,0 @@ -<!-- - - Copyright (C) 2004, 2005, 2007 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 1.5.18.18 2007/01/30 00:23:45 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 V1.71.1"> -</head> -<body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"><div class="refentry" lang="en"> -<a name="id2476275"></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="id2543348"></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="id2543361"></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="id2543425"></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="id2543573"></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="id2543656"></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> |