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diff --git a/lib/liblwres/man/lwres_noop.docbook b/lib/liblwres/man/lwres_noop.docbook new file mode 100644 index 000000000..18762e515 --- /dev/null +++ b/lib/liblwres/man/lwres_noop.docbook @@ -0,0 +1,229 @@ +<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook V4.1//EN"> +<!-- + - Copyright (C) 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 INTERNET SOFTWARE CONSORTIUM + - DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL + - IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL + - INTERNET SOFTWARE CONSORTIUM 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_noop.docbook,v 1.1 2004/03/15 20:35:25 as Exp $ --> + +<refentry> + +<refentryinfo> +<date>Jun 30, 2000</date> +</refentryinfo> + +<refmeta> +<refentrytitle>lwres_noop</refentrytitle> +<manvolnum>3</manvolnum> +<refmiscinfo>BIND9</refmiscinfo> +</refmeta> + +<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 *ctx</paramdef> +<paramdef>lwres_nooprequest_t *req</paramdef> +<paramdef>lwres_lwpacket_t *pkt</paramdef> +<paramdef>lwres_buffer_t *b</paramdef> +</funcprototype> +<funcprototype> +<funcdef> +lwres_result_t +<function>lwres_noopresponse_render</function></funcdef> +<paramdef>lwres_context_t *ctx</paramdef> +<paramdef>lwres_noopresponse_t *req</paramdef> +<paramdef>lwres_lwpacket_t *pkt</paramdef> +<paramdef>lwres_buffer_t *b</paramdef> +</funcprototype> +<funcprototype> +<funcdef> +lwres_result_t +<function>lwres_nooprequest_parse</function></funcdef> +<paramdef>lwres_context_t *ctx</paramdef> +<paramdef>lwres_buffer_t *b</paramdef> +<paramdef>lwres_lwpacket_t *pkt</paramdef> +<paramdef>lwres_nooprequest_t **structp</paramdef> +</funcprototype> +<funcprototype> +<funcdef> +lwres_result_t +<function>lwres_noopresponse_parse</function></funcdef> +<paramdef>lwres_context_t *ctx</paramdef> +<paramdef>lwres_buffer_t *b</paramdef> +<paramdef>lwres_lwpacket_t *pkt</paramdef> +<paramdef>lwres_noopresponse_t **structp</paramdef> +</funcprototype> +<funcprototype> +<funcdef> +void +<function>lwres_noopresponse_free</function></funcdef> +<paramdef>lwres_context_t *ctx</paramdef> +<paramdef>lwres_noopresponse_t **structp</paramdef> +</funcprototype> +<funcprototype> +<funcdef> +void +<function>lwres_nooprequest_free</function></funcdef> +<paramdef>lwres_context_t *ctx</paramdef> +<paramdef>lwres_nooprequest_t **structp</paramdef> +</funcprototype> +</funcsynopsis> +</refsynopsisdiv> +<refsect1> +<title>DESCRIPTION</title> +<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 lighweight 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. +<programlisting> +#define LWRES_OPCODE_NOOP 0x00000000U + +typedef struct { + lwres_uint16_t datalength; + unsigned char *data; +} lwres_nooprequest_t; + +typedef struct { + lwres_uint16_t datalength; + unsigned char *data; +} lwres_noopresponse_t; +</programlisting> +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> + +</refsect1> +<refsect1> +<title>RETURN VALUES</title> +<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> +</refsect1> +<refsect1> +<title>SEE ALSO</title> +<para> +<citerefentry> +<refentrytitle>lwres_packet</refentrytitle><manvolnum>3 +</manvolnum> +</citerefentry> +</para> +</refsect1> +</refentry> |