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diff --git a/lib/liblwres/man/lwres_noop.html b/lib/liblwres/man/lwres_noop.html new file mode 100644 index 000000000..fdb5da103 --- /dev/null +++ b/lib/liblwres/man/lwres_noop.html @@ -0,0 +1,409 @@ +<!-- + - 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 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. +--> +<HTML +><HEAD +><TITLE +>lwres_noop</TITLE +><META +NAME="GENERATOR" +CONTENT="Modular DocBook HTML Stylesheet Version 1.61 +"></HEAD +><BODY +CLASS="REFENTRY" +BGCOLOR="#FFFFFF" +TEXT="#000000" +LINK="#0000FF" +VLINK="#840084" +ALINK="#0000FF" +><H1 +><A +NAME="AEN1" +>lwres_noop</A +></H1 +><DIV +CLASS="REFNAMEDIV" +><A +NAME="AEN8" +></A +><H2 +>Name</H2 +>lwres_nooprequest_render, lwres_noopresponse_render, lwres_nooprequest_parse, lwres_noopresponse_parse, lwres_noopresponse_free, lwres_nooprequest_free -- lightweight resolver no-op message handling</DIV +><DIV +CLASS="REFSYNOPSISDIV" +><A +NAME="AEN16" +></A +><H2 +>Synopsis</H2 +><DIV +CLASS="FUNCSYNOPSIS" +><A +NAME="AEN17" +></A +><P +></P +><PRE +CLASS="FUNCSYNOPSISINFO" +>#include <lwres/lwres.h></PRE +><P +><CODE +><CODE +CLASS="FUNCDEF" +>lwres_result_t +lwres_nooprequest_render</CODE +>(lwres_context_t *ctx, lwres_nooprequest_t *req, lwres_lwpacket_t *pkt, lwres_buffer_t *b);</CODE +></P +><P +><CODE +><CODE +CLASS="FUNCDEF" +>lwres_result_t +lwres_noopresponse_render</CODE +>(lwres_context_t *ctx, lwres_noopresponse_t *req, lwres_lwpacket_t *pkt, lwres_buffer_t *b);</CODE +></P +><P +><CODE +><CODE +CLASS="FUNCDEF" +>lwres_result_t +lwres_nooprequest_parse</CODE +>(lwres_context_t *ctx, lwres_buffer_t *b, lwres_lwpacket_t *pkt, lwres_nooprequest_t **structp);</CODE +></P +><P +><CODE +><CODE +CLASS="FUNCDEF" +>lwres_result_t +lwres_noopresponse_parse</CODE +>(lwres_context_t *ctx, lwres_buffer_t *b, lwres_lwpacket_t *pkt, lwres_noopresponse_t **structp);</CODE +></P +><P +><CODE +><CODE +CLASS="FUNCDEF" +>void +lwres_noopresponse_free</CODE +>(lwres_context_t *ctx, lwres_noopresponse_t **structp);</CODE +></P +><P +><CODE +><CODE +CLASS="FUNCDEF" +>void +lwres_nooprequest_free</CODE +>(lwres_context_t *ctx, lwres_nooprequest_t **structp);</CODE +></P +><P +></P +></DIV +></DIV +><DIV +CLASS="REFSECT1" +><A +NAME="AEN57" +></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 <B +CLASS="COMMAND" +>ping</B +> 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 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 — +<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 +<TT +CLASS="FILENAME" +>lwres/lwres.h</TT +>. + +They are shown below. +<PRE +CLASS="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;</PRE +> +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 +><TT +CLASS="FUNCTION" +>lwres_nooprequest_render()</TT +> uses resolver +context <TT +CLASS="PARAMETER" +><I +>ctx</I +></TT +> to convert no-op request structure +<TT +CLASS="PARAMETER" +><I +>req</I +></TT +> to canonical format. The packet header +structure <TT +CLASS="PARAMETER" +><I +>pkt</I +></TT +> is initialised and transferred to +buffer <TT +CLASS="PARAMETER" +><I +>b</I +></TT +>. The contents of +<TT +CLASS="PARAMETER" +><I +>*req</I +></TT +> are then appended to the buffer in +canonical format. <TT +CLASS="FUNCTION" +>lwres_noopresponse_render()</TT +> +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 +><TT +CLASS="FUNCTION" +>lwres_nooprequest_parse()</TT +> uses context +<TT +CLASS="PARAMETER" +><I +>ctx</I +></TT +> to convert the contents of packet +<TT +CLASS="PARAMETER" +><I +>pkt</I +></TT +> to a <SPAN +CLASS="TYPE" +>lwres_nooprequest_t</SPAN +> +structure. Buffer <TT +CLASS="PARAMETER" +><I +>b</I +></TT +> 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 +<TT +CLASS="PARAMETER" +><I +>*structp</I +></TT +>. +<TT +CLASS="FUNCTION" +>lwres_noopresponse_parse()</TT +> offers the same +semantics as <TT +CLASS="FUNCTION" +>lwres_nooprequest_parse()</TT +> except it +yields a <SPAN +CLASS="TYPE" +>lwres_noopresponse_t</SPAN +> structure.</P +><P +><TT +CLASS="FUNCTION" +>lwres_noopresponse_free()</TT +> and +<TT +CLASS="FUNCTION" +>lwres_nooprequest_free()</TT +> release the memory in +resolver context <TT +CLASS="PARAMETER" +><I +>ctx</I +></TT +> that was allocated to the +<SPAN +CLASS="TYPE" +>lwres_noopresponse_t</SPAN +> or <SPAN +CLASS="TYPE" +>lwres_nooprequest_t</SPAN +> +structures referenced via <TT +CLASS="PARAMETER" +><I +>structp</I +></TT +>.</P +></DIV +><DIV +CLASS="REFSECT1" +><A +NAME="AEN95" +></A +><H2 +>RETURN VALUES</H2 +><P +>The no-op opcode functions +<TT +CLASS="FUNCTION" +>lwres_nooprequest_render()</TT +>, + +<TT +CLASS="FUNCTION" +>lwres_noopresponse_render()</TT +> +<TT +CLASS="FUNCTION" +>lwres_nooprequest_parse()</TT +> +and +<TT +CLASS="FUNCTION" +>lwres_noopresponse_parse()</TT +> +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 +<TT +CLASS="PARAMETER" +><I +>b</I +></TT +> +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. +<TT +CLASS="FUNCTION" +>lwres_nooprequest_parse()</TT +> +and +<TT +CLASS="FUNCTION" +>lwres_noopresponse_parse()</TT +> +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 +<TT +CLASS="CONSTANT" +>pktflags</TT +> +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="REFSECT1" +><A +NAME="AEN114" +></A +><H2 +>SEE ALSO</H2 +><P +><SPAN +CLASS="CITEREFENTRY" +><SPAN +CLASS="REFENTRYTITLE" +>lwres_packet</SPAN +>(3)</SPAN +></P +></DIV +></BODY +></HTML +>
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