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diff --git a/lib/lwres/man/lwres_noop.docbook b/lib/lwres/man/lwres_noop.docbook new file mode 100644 index 0000000..64ab392 --- /dev/null +++ b/lib/lwres/man/lwres_noop.docbook @@ -0,0 +1,249 @@ +<!DOCTYPE book [ +<!ENTITY mdash "—">]> +<!-- + - Copyright (C) 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/. + - + - See the COPYRIGHT file distributed with this work for additional + - information regarding copyright ownership. +--> + +<!-- Converted by db4-upgrade version 1.0 --> +<refentry xmlns:db="http://docbook.org/ns/docbook" version="5.0"> + <info> + <date>2007-06-18</date> + </info> + <refentryinfo> + <corpname>ISC</corpname> + <corpauthor>Internet Systems Consortium, Inc.</corpauthor> + </refentryinfo> + + <refmeta> + <refentrytitle>lwres_noop</refentrytitle> + <manvolnum>3</manvolnum> + <refmiscinfo>BIND9</refmiscinfo> + </refmeta> + + <docinfo> + <copyright> + <year>2000</year> + <year>2001</year> + <year>2004</year> + <year>2005</year> + <year>2007</year> + <year>2014</year> + <year>2015</year> + <year>2016</year> + <year>2018</year> + <year>2019</year> + <holder>Internet Systems Consortium, Inc. ("ISC")</holder> + </copyright> + </docinfo> + + <refnamediv> + <refname>lwres_nooprequest_render</refname> + <refname>lwres_noopresponse_render</refname> + <refname>lwres_nooprequest_parse</refname> + <refname>lwres_noopresponse_parse</refname> + <refname>lwres_noopresponse_free</refname> + <refname>lwres_nooprequest_free</refname> + <refpurpose>lightweight resolver no-op message handling</refpurpose> + </refnamediv> + <refsynopsisdiv> + <funcsynopsis> +<funcsynopsisinfo> +#include <lwres/lwres.h></funcsynopsisinfo> +<funcprototype> + <funcdef> +lwres_result_t +<function>lwres_nooprequest_render</function></funcdef> + <paramdef>lwres_context_t *<parameter>ctx</parameter></paramdef> + <paramdef>lwres_nooprequest_t *<parameter>req</parameter></paramdef> + <paramdef>lwres_lwpacket_t *<parameter>pkt</parameter></paramdef> + <paramdef>lwres_buffer_t *<parameter>b</parameter></paramdef> + </funcprototype> +<funcprototype> + <funcdef> +lwres_result_t +<function>lwres_noopresponse_render</function></funcdef> + <paramdef>lwres_context_t *<parameter>ctx</parameter></paramdef> + <paramdef>lwres_noopresponse_t *<parameter>req</parameter></paramdef> + <paramdef>lwres_lwpacket_t *<parameter>pkt</parameter></paramdef> + <paramdef>lwres_buffer_t *<parameter>b</parameter></paramdef> + </funcprototype> +<funcprototype> + <funcdef> +lwres_result_t +<function>lwres_nooprequest_parse</function></funcdef> + <paramdef>lwres_context_t *<parameter>ctx</parameter></paramdef> + <paramdef>lwres_buffer_t *<parameter>b</parameter></paramdef> + <paramdef>lwres_lwpacket_t *<parameter>pkt</parameter></paramdef> + <paramdef>lwres_nooprequest_t **<parameter>structp</parameter></paramdef> + </funcprototype> +<funcprototype> + <funcdef> +lwres_result_t +<function>lwres_noopresponse_parse</function></funcdef> + <paramdef>lwres_context_t *<parameter>ctx</parameter></paramdef> + <paramdef>lwres_buffer_t *<parameter>b</parameter></paramdef> + <paramdef>lwres_lwpacket_t *<parameter>pkt</parameter></paramdef> + <paramdef>lwres_noopresponse_t **<parameter>structp</parameter></paramdef> + </funcprototype> +<funcprototype> + <funcdef> +void +<function>lwres_noopresponse_free</function></funcdef> + <paramdef>lwres_context_t *<parameter>ctx</parameter></paramdef> + <paramdef>lwres_noopresponse_t **<parameter>structp</parameter></paramdef> + </funcprototype> +<funcprototype> + <funcdef> +void +<function>lwres_nooprequest_free</function></funcdef> + <paramdef>lwres_context_t *<parameter>ctx</parameter></paramdef> + <paramdef>lwres_nooprequest_t **<parameter>structp</parameter></paramdef> + </funcprototype> +</funcsynopsis> + </refsynopsisdiv> + <refsection><info><title>DESCRIPTION</title></info> + + <para> + These are low-level routines for creating and parsing + lightweight resolver no-op request and response messages. + </para> + <para> + The no-op message is analogous to a <command>ping</command> + 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. + </para> + <para> + There are four main functions for the no-op opcode. + One render function converts a no-op request structure — + <type>lwres_nooprequest_t</type> — + 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 — + <type>lwres_noopresponse_t</type> + to the canonical format. + This is complemented by a parse function which converts a packet in + canonical format to a no-op response structure. + </para> + <para> + These structures are defined in + <filename>lwres/lwres.h</filename>. + + They are shown below. + </para> + <para><programlisting> +#define LWRES_OPCODE_NOOP 0x00000000U +</programlisting> + </para> + <para><programlisting> +typedef struct { + uint16_t datalength; + unsigned char *data; +} lwres_nooprequest_t; +</programlisting> + </para> + <para><programlisting> +typedef struct { + uint16_t datalength; + unsigned char *data; +} lwres_noopresponse_t; +</programlisting> + </para> + <para> + 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. + </para> + + <para><function>lwres_nooprequest_render()</function> + uses resolver context <parameter>ctx</parameter> to convert + no-op request structure <parameter>req</parameter> to canonical + format. The packet header structure <parameter>pkt</parameter> + is initialised and transferred to buffer + <parameter>b</parameter>. The contents of + <parameter>*req</parameter> are then appended to the buffer in + canonical format. + <function>lwres_noopresponse_render()</function> performs the + same task, except it converts a no-op response structure + <type>lwres_noopresponse_t</type> to the lightweight resolver's + canonical format. + </para> + + <para><function>lwres_nooprequest_parse()</function> + uses context <parameter>ctx</parameter> to convert the contents + of packet <parameter>pkt</parameter> to a + <type>lwres_nooprequest_t</type> structure. Buffer + <parameter>b</parameter> provides space to be used for storing + this structure. When the function succeeds, the resulting + <type>lwres_nooprequest_t</type> is made available through + <parameter>*structp</parameter>. + <function>lwres_noopresponse_parse()</function> offers the same + semantics as <function>lwres_nooprequest_parse()</function> + except it yields a <type>lwres_noopresponse_t</type> structure. + </para> + + <para><function>lwres_noopresponse_free()</function> + and <function>lwres_nooprequest_free()</function> release the + memory in resolver context <parameter>ctx</parameter> that was + allocated to the <type>lwres_noopresponse_t</type> or + <type>lwres_nooprequest_t</type> structures referenced via + <parameter>structp</parameter>. + </para> + + </refsection> + <refsection><info><title>RETURN VALUES</title></info> + + <para> + The no-op opcode functions + <function>lwres_nooprequest_render()</function>, + + <function>lwres_noopresponse_render()</function> + <function>lwres_nooprequest_parse()</function> + and + <function>lwres_noopresponse_parse()</function> + all return + <errorcode>LWRES_R_SUCCESS</errorcode> + on success. + They return + <errorcode>LWRES_R_NOMEMORY</errorcode> + if memory allocation fails. + <errorcode>LWRES_R_UNEXPECTEDEND</errorcode> + is returned if the available space in the buffer + <parameter>b</parameter> + is too small to accommodate the packet header or the + <type>lwres_nooprequest_t</type> + and + <type>lwres_noopresponse_t</type> + structures. + <function>lwres_nooprequest_parse()</function> + and + <function>lwres_noopresponse_parse()</function> + will return + <errorcode>LWRES_R_UNEXPECTEDEND</errorcode> + if the buffer is not empty after decoding the received packet. + These functions will return + <errorcode>LWRES_R_FAILURE</errorcode> + if + <constant>pktflags</constant> + in the packet header structure + <type>lwres_lwpacket_t</type> + indicate that the packet is not a response to an earlier query. + </para> + </refsection> + <refsection><info><title>SEE ALSO</title></info> + + <para><citerefentry> + <refentrytitle>lwres_packet</refentrytitle><manvolnum>3</manvolnum> + </citerefentry> + </para> + </refsection> +</refentry> |