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diff --git a/lib/lwres/man/lwres_noop.html b/lib/lwres/man/lwres_noop.html new file mode 100644 index 0000000..0e9cea7 --- /dev/null +++ b/lib/lwres/man/lwres_noop.html @@ -0,0 +1,298 @@ +<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> +<!-- + - Copyright (C) 2000, 2001, 2004, 2005, 2007, 2014-2016, 2018, 2019 Internet Systems Consortium, Inc. ("ISC") + - + - This Source Code Form is subject to the terms of the Mozilla Public + - License, v. 2.0. If a copy of the MPL was not distributed with this + - file, You can obtain one at http://mozilla.org/MPL/2.0/. +--> +<html lang="en"> +<head> +<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1"> +<title>lwres_noop</title> +<meta name="generator" content="DocBook XSL Stylesheets V1.78.1"> +</head> +<body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"><div class="refentry"> +<a name="id-1"></a><div class="titlepage"></div> + + + + + + + + <div class="refnamediv"> +<h2>Name</h2> +<p> + lwres_nooprequest_render, + lwres_noopresponse_render, + lwres_nooprequest_parse, + lwres_noopresponse_parse, + lwres_noopresponse_free, + lwres_nooprequest_free + — lightweight resolver no-op message handling + </p> +</div> + <div class="refsynopsisdiv"> +<h2>Synopsis</h2> + <div class="funcsynopsis"> +<pre class="funcsynopsisinfo"> +#include <lwres/lwres.h></pre> +<table border="0" class="funcprototype-table" summary="Function synopsis" style="cellspacing: 0; cellpadding: 0;"> +<tr> +<td><code class="funcdef"> +lwres_result_t +<b class="fsfunc">lwres_nooprequest_render</b>(</code></td> +<td>lwres_context_t *<var class="pdparam">ctx</var>, </td> +</tr> +<tr> +<td> </td> +<td>lwres_nooprequest_t *<var class="pdparam">req</var>, </td> +</tr> +<tr> +<td> </td> +<td>lwres_lwpacket_t *<var class="pdparam">pkt</var>, </td> +</tr> +<tr> +<td> </td> +<td>lwres_buffer_t *<var class="pdparam">b</var><code>)</code>;</td> +</tr> +</table> +<div class="funcprototype-spacer"> </div> +<table border="0" class="funcprototype-table" summary="Function synopsis" style="cellspacing: 0; cellpadding: 0;"> +<tr> +<td><code class="funcdef"> +lwres_result_t +<b class="fsfunc">lwres_noopresponse_render</b>(</code></td> +<td>lwres_context_t *<var class="pdparam">ctx</var>, </td> +</tr> +<tr> +<td> </td> +<td>lwres_noopresponse_t *<var class="pdparam">req</var>, </td> +</tr> +<tr> +<td> </td> +<td>lwres_lwpacket_t *<var class="pdparam">pkt</var>, </td> +</tr> +<tr> +<td> </td> +<td>lwres_buffer_t *<var class="pdparam">b</var><code>)</code>;</td> +</tr> +</table> +<div class="funcprototype-spacer"> </div> +<table border="0" class="funcprototype-table" summary="Function synopsis" style="cellspacing: 0; cellpadding: 0;"> +<tr> +<td><code class="funcdef"> +lwres_result_t +<b class="fsfunc">lwres_nooprequest_parse</b>(</code></td> +<td>lwres_context_t *<var class="pdparam">ctx</var>, </td> +</tr> +<tr> +<td> </td> +<td>lwres_buffer_t *<var class="pdparam">b</var>, </td> +</tr> +<tr> +<td> </td> +<td>lwres_lwpacket_t *<var class="pdparam">pkt</var>, </td> +</tr> +<tr> +<td> </td> +<td>lwres_nooprequest_t **<var class="pdparam">structp</var><code>)</code>;</td> +</tr> +</table> +<div class="funcprototype-spacer"> </div> +<table border="0" class="funcprototype-table" summary="Function synopsis" style="cellspacing: 0; cellpadding: 0;"> +<tr> +<td><code class="funcdef"> +lwres_result_t +<b class="fsfunc">lwres_noopresponse_parse</b>(</code></td> +<td>lwres_context_t *<var class="pdparam">ctx</var>, </td> +</tr> +<tr> +<td> </td> +<td>lwres_buffer_t *<var class="pdparam">b</var>, </td> +</tr> +<tr> +<td> </td> +<td>lwres_lwpacket_t *<var class="pdparam">pkt</var>, </td> +</tr> +<tr> +<td> </td> +<td>lwres_noopresponse_t **<var class="pdparam">structp</var><code>)</code>;</td> +</tr> +</table> +<div class="funcprototype-spacer"> </div> +<table border="0" class="funcprototype-table" summary="Function synopsis" style="cellspacing: 0; cellpadding: 0;"> +<tr> +<td><code class="funcdef"> +void +<b class="fsfunc">lwres_noopresponse_free</b>(</code></td> +<td>lwres_context_t *<var class="pdparam">ctx</var>, </td> +</tr> +<tr> +<td> </td> +<td>lwres_noopresponse_t **<var class="pdparam">structp</var><code>)</code>;</td> +</tr> +</table> +<div class="funcprototype-spacer"> </div> +<table border="0" class="funcprototype-table" summary="Function synopsis" style="cellspacing: 0; cellpadding: 0;"> +<tr> +<td><code class="funcdef"> +void +<b class="fsfunc">lwres_nooprequest_free</b>(</code></td> +<td>lwres_context_t *<var class="pdparam">ctx</var>, </td> +</tr> +<tr> +<td> </td> +<td>lwres_nooprequest_t **<var class="pdparam">structp</var><code>)</code>;</td> +</tr> +</table> +<div class="funcprototype-spacer"> </div> +</div> + </div> + <div class="refsection"> +<a name="id-1.7"></a><h2>DESCRIPTION</h2> + + <p> + These are low-level routines for creating and parsing + lightweight resolver no-op request and response messages. + </p> + <p> + The no-op message is analogous to a <span class="command"><strong>ping</strong></span> + packet: + a packet is sent to the resolver daemon and is simply echoed back. + The opcode is intended to allow a client to determine if the server is + operational or not. + </p> + <p> + There are four main functions for the no-op opcode. + One render function converts a no-op request structure — + <span class="type">lwres_nooprequest_t</span> — + to the lightweight resolver's canonical format. + It is complemented by a parse function that converts a packet in this + canonical format to a no-op request structure. + Another render function converts the no-op response structure — + <span class="type">lwres_noopresponse_t</span> + to the canonical format. + This is complemented by a parse function which converts a packet in + canonical format to a no-op response structure. + </p> + <p> + These structures are defined in + <code class="filename">lwres/lwres.h</code>. + + They are shown below. + </p> + <pre class="programlisting"> +#define LWRES_OPCODE_NOOP 0x00000000U +</pre> +<p> + </p> + <pre class="programlisting"> +typedef struct { + uint16_t datalength; + unsigned char *data; +} lwres_nooprequest_t; +</pre> +<p> + </p> + <pre class="programlisting"> +typedef struct { + uint16_t datalength; + unsigned char *data; +} lwres_noopresponse_t; +</pre> +<p> + </p> + <p> + Although the structures have different types, they are identical. + This is because the no-op opcode simply echos whatever data was sent: + the response is therefore identical to the request. + </p> + + <p><code class="function">lwres_nooprequest_render()</code> + uses resolver context <em class="parameter"><code>ctx</code></em> to convert + no-op request structure <em class="parameter"><code>req</code></em> to canonical + format. The packet header structure <em class="parameter"><code>pkt</code></em> + is initialised and transferred to buffer + <em class="parameter"><code>b</code></em>. The contents of + <em class="parameter"><code>*req</code></em> are then appended to the buffer in + canonical format. + <code class="function">lwres_noopresponse_render()</code> performs the + same task, except it converts a no-op response structure + <span class="type">lwres_noopresponse_t</span> to the lightweight resolver's + canonical format. + </p> + + <p><code class="function">lwres_nooprequest_parse()</code> + uses context <em class="parameter"><code>ctx</code></em> to convert the contents + of packet <em class="parameter"><code>pkt</code></em> to a + <span class="type">lwres_nooprequest_t</span> structure. Buffer + <em class="parameter"><code>b</code></em> provides space to be used for storing + this structure. When the function succeeds, the resulting + <span class="type">lwres_nooprequest_t</span> is made available through + <em class="parameter"><code>*structp</code></em>. + <code class="function">lwres_noopresponse_parse()</code> offers the same + semantics as <code class="function">lwres_nooprequest_parse()</code> + except it yields a <span class="type">lwres_noopresponse_t</span> structure. + </p> + + <p><code class="function">lwres_noopresponse_free()</code> + and <code class="function">lwres_nooprequest_free()</code> release the + memory in resolver context <em class="parameter"><code>ctx</code></em> that was + allocated to the <span class="type">lwres_noopresponse_t</span> or + <span class="type">lwres_nooprequest_t</span> structures referenced via + <em class="parameter"><code>structp</code></em>. + </p> + + </div> + <div class="refsection"> +<a name="id-1.8"></a><h2>RETURN VALUES</h2> + + <p> + The no-op opcode functions + <code class="function">lwres_nooprequest_render()</code>, + + <code class="function">lwres_noopresponse_render()</code> + <code class="function">lwres_nooprequest_parse()</code> + and + <code class="function">lwres_noopresponse_parse()</code> + all return + <span class="errorcode">LWRES_R_SUCCESS</span> + on success. + They return + <span class="errorcode">LWRES_R_NOMEMORY</span> + if memory allocation fails. + <span class="errorcode">LWRES_R_UNEXPECTEDEND</span> + is returned if the available space in the buffer + <em class="parameter"><code>b</code></em> + is too small to accommodate the packet header or the + <span class="type">lwres_nooprequest_t</span> + and + <span class="type">lwres_noopresponse_t</span> + structures. + <code class="function">lwres_nooprequest_parse()</code> + and + <code class="function">lwres_noopresponse_parse()</code> + will return + <span class="errorcode">LWRES_R_UNEXPECTEDEND</span> + if the buffer is not empty after decoding the received packet. + These functions will return + <span class="errorcode">LWRES_R_FAILURE</span> + if + <code class="constant">pktflags</code> + in the packet header structure + <span class="type">lwres_lwpacket_t</span> + indicate that the packet is not a response to an earlier query. + </p> + </div> + <div class="refsection"> +<a name="id-1.9"></a><h2>SEE ALSO</h2> + + <p><span class="citerefentry"> + <span class="refentrytitle">lwres_packet</span>(3) + </span> + </p> + </div> +</div></body> +</html> |