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15225N/A
15225N/A<HTML
15225N/A><HEAD
15225N/A><TITLE
15225N/A>lwres_gabn</TITLE
15225N/A><META
15225N/ANAME="GENERATOR"
15225N/ACONTENT="Modular DocBook HTML Stylesheet Version 1.73
15225N/A"></HEAD
15225N/A><BODY
15225N/ACLASS="REFENTRY"
15225N/ABGCOLOR="#FFFFFF"
15225N/ATEXT="#000000"
15225N/ALINK="#0000FF"
15225N/AVLINK="#840084"
15225N/AALINK="#0000FF"
15225N/A><H1
15225N/A><A
15225N/ANAME="AEN1"
15225N/A>lwres_gabn</A
15225N/A></H1
15225N/A><DIV
15225N/ACLASS="REFNAMEDIV"
15225N/A><A
15225N/ANAME="AEN8"
15225N/A></A
15225N/A><H2
15225N/A>Name</H2
15225N/A>lwres_gabnrequest_render, lwres_gabnresponse_render, lwres_gabnrequest_parse, lwres_gabnresponse_parse, lwres_gabnresponse_free, lwres_gabnrequest_free&nbsp;--&nbsp;lightweight resolver getaddrbyname message handling</DIV
15225N/A><DIV
15225N/ACLASS="REFSYNOPSISDIV"
15225N/A><A
15225N/ANAME="AEN16"
15225N/A></A
15225N/A><H2
15225N/A>Synopsis</H2
15225N/A><DIV
15225N/ACLASS="FUNCSYNOPSIS"
15225N/A><A
15225N/ANAME="AEN17"
15225N/A></A
15225N/A><P
15225N/A></P
15225N/A><PRE
15225N/ACLASS="FUNCSYNOPSISINFO"
15225N/A>#include &lt;lwres/lwres.h&gt;</PRE
15225N/A><P
15225N/A><CODE
15225N/A><CODE
15225N/ACLASS="FUNCDEF"
15225N/A>lwres_result_t
15225N/Alwres_gabnrequest_render</CODE
15225N/A>(lwres_context_t *ctx, lwres_gabnrequest_t *req, lwres_lwpacket_t *pkt, lwres_buffer_t *b);</CODE
15225N/A></P
15225N/A><P
15225N/A><CODE
15225N/A><CODE
15225N/ACLASS="FUNCDEF"
15225N/A>lwres_result_t
15225N/Alwres_gabnresponse_render</CODE
15225N/A>(lwres_context_t *ctx, lwres_gabnresponse_t *req, lwres_lwpacket_t *pkt, lwres_buffer_t *b);</CODE
15225N/A></P
15225N/A><P
15225N/A><CODE
15225N/A><CODE
15225N/ACLASS="FUNCDEF"
15225N/A>lwres_result_t
15225N/Alwres_gabnrequest_parse</CODE
15225N/A>(lwres_context_t *ctx, lwres_buffer_t *b, lwres_lwpacket_t *pkt, lwres_gabnrequest_t **structp);</CODE
15225N/A></P
15225N/A><P
15225N/A><CODE
15225N/A><CODE
15225N/ACLASS="FUNCDEF"
15225N/A>lwres_result_t
15225N/Alwres_gabnresponse_parse</CODE
15225N/A>(lwres_context_t *ctx, lwres_buffer_t *b, lwres_lwpacket_t *pkt, lwres_gabnresponse_t **structp);</CODE
15225N/A></P
15225N/A><P
15225N/A><CODE
15225N/A><CODE
15225N/ACLASS="FUNCDEF"
15225N/A>void
15225N/Alwres_gabnresponse_free</CODE
15225N/A>(lwres_context_t *ctx, lwres_gabnresponse_t **structp);</CODE
15225N/A></P
15225N/A><P
15225N/A><CODE
15225N/A><CODE
15225N/ACLASS="FUNCDEF"
15225N/A>void
15225N/Alwres_gabnrequest_free</CODE
15225N/A>(lwres_context_t *ctx, lwres_gabnrequest_t **structp);</CODE
15225N/A></P
15225N/A><P
15225N/A></P
15225N/A></DIV
15225N/A></DIV
15225N/A><DIV
15225N/ACLASS="REFSECT1"
15225N/A><A
15225N/ANAME="AEN57"
15225N/A></A
15225N/A><H2
15225N/A>DESCRIPTION</H2
15225N/A><P
15225N/A>These are low-level routines for creating and parsing
15225N/Alightweight resolver name-to-address lookup request and
15225N/Aresponse messages.</P
15225N/A><P
15225N/A>There are four main functions for the getaddrbyname opcode.
15225N/AOne render function converts a getaddrbyname request structure &mdash;
15225N/A<SPAN
15225N/ACLASS="TYPE"
15225N/A>lwres_gabnrequest_t</SPAN
15225N/A> &mdash;
15225N/Ato the lighweight resolver's canonical format.
15225N/AIt is complemented by a parse function that converts a packet in this
15225N/Acanonical format to a getaddrbyname request structure.
15225N/AAnother render function converts the getaddrbyname response structure &mdash;
15225N/A<SPAN
15225N/ACLASS="TYPE"
15225N/A>lwres_gabnresponse_t</SPAN
15225N/A> &mdash;
15225N/Ato the canonical format.
15225N/AThis is complemented by a parse function which converts a packet in
15225N/Acanonical format to a getaddrbyname response structure.</P
15225N/A><P
15225N/A>These structures are defined in
15225N/A<TT
15225N/ACLASS="FILENAME"
15225N/A>&lt;lwres/lwres.h&gt;</TT
15225N/A>.
15225N/AThey are shown below.
15225N/A<PRE
15225N/ACLASS="PROGRAMLISTING"
15225N/A>#define LWRES_OPCODE_GETADDRSBYNAME 0x00010001U
15225N/A
15225N/Atypedef struct lwres_addr lwres_addr_t;
15225N/Atypedef LWRES_LIST(lwres_addr_t) lwres_addrlist_t;
15225N/A
15225N/Atypedef struct {
15225N/A lwres_uint32_t flags;
15225N/A lwres_uint32_t addrtypes;
15225N/A lwres_uint16_t namelen;
15225N/A char *name;
15225N/A} lwres_gabnrequest_t;
15225N/A
15225N/Atypedef struct {
15225N/A lwres_uint32_t flags;
15225N/A lwres_uint16_t naliases;
15225N/A lwres_uint16_t naddrs;
15225N/A char *realname;
15225N/A char **aliases;
15225N/A lwres_uint16_t realnamelen;
15225N/A lwres_uint16_t *aliaslen;
15225N/A lwres_addrlist_t addrs;
15225N/A void *base;
15225N/A size_t baselen;
15225N/A} lwres_gabnresponse_t;</PRE
15225N/A></P
15225N/A><P
15225N/A><TT
15225N/ACLASS="FUNCTION"
15225N/A>lwres_gabnrequest_render()</TT
15225N/A>
15225N/Auses resolver context
15225N/A<TT
15225N/ACLASS="PARAMETER"
15225N/A><I
15225N/A>ctx</I
15225N/A></TT
15225N/A>
15225N/Ato convert getaddrbyname request structure
15225N/A<TT
15225N/ACLASS="PARAMETER"
15225N/A><I
15225N/A>req</I
15225N/A></TT
15225N/A>
15225N/Ato canonical format.
15225N/AThe packet header structure
15225N/A<TT
15225N/ACLASS="PARAMETER"
15225N/A><I
15225N/A>pkt</I
15225N/A></TT
15225N/A>
15225N/Ais initialised and transferred to
15225N/Abuffer
15225N/A<TT
15225N/ACLASS="PARAMETER"
15225N/A><I
15225N/A>b</I
15225N/A></TT
15225N/A>.
15225N/A
15225N/AThe contents of
15225N/A<TT
15225N/ACLASS="PARAMETER"
15225N/A><I
15225N/A>*req</I
15225N/A></TT
15225N/A>
15225N/Aare then appended to the buffer in canonical format.
15225N/A<TT
15225N/ACLASS="FUNCTION"
15225N/A>lwres_gabnresponse_render()</TT
15225N/A>
15225N/Aperforms the same task, except it converts a getaddrbyname response structure
15225N/A<SPAN
15225N/ACLASS="TYPE"
15225N/A>lwres_gabnresponse_t</SPAN
15225N/A>
15225N/Ato the lightweight resolver's canonical format.</P
15225N/A><P
15225N/A><TT
15225N/ACLASS="FUNCTION"
15225N/A>lwres_gabnrequest_parse()</TT
15225N/A>
15225N/Auses context
15225N/A<TT
15225N/ACLASS="PARAMETER"
15225N/A><I
15225N/A>ctx</I
15225N/A></TT
15225N/A>
15225N/Ato convert the contents of packet
15225N/A<TT
15225N/ACLASS="PARAMETER"
15225N/A><I
15225N/A>pkt</I
15225N/A></TT
15225N/A>
15225N/Ato a
15225N/A<SPAN
15225N/ACLASS="TYPE"
15225N/A>lwres_gabnrequest_t</SPAN
15225N/A>
15225N/Astructure.
15225N/ABuffer
15225N/A<TT
15225N/ACLASS="PARAMETER"
15225N/A><I
15225N/A>b</I
15225N/A></TT
15225N/A>
15225N/Aprovides space to be used for storing this structure.
15225N/AWhen the function succeeds, the resulting
15225N/A<SPAN
15153N/ACLASS="TYPE"
15153N/A>lwres_gabnrequest_t</SPAN
10017N/A>
10017N/Ais made available through
10017N/A<TT
10017N/ACLASS="PARAMETER"
15153N/A><I
15153N/A>*structp</I
10017N/A></TT
10017N/A>.
10017N/A
15153N/A<TT
15153N/ACLASS="FUNCTION"
15153N/A>lwres_gabnresponse_parse()</TT
15153N/A>
15153N/Aoffers the same semantics as
15153N/A<TT
15153N/ACLASS="FUNCTION"
15153N/A>lwres_gabnrequest_parse()</TT
10017N/A>
15153N/Aexcept it yields a
10017N/A<SPAN
10017N/ACLASS="TYPE"
10017N/A>lwres_gabnresponse_t</SPAN
10017N/A>
10017N/Astructure.</P
10017N/A><P
15153N/A><TT
10017N/ACLASS="FUNCTION"
10017N/A>lwres_gabnresponse_free()</TT
10017N/A>
10017N/Aand
15153N/A<TT
10017N/ACLASS="FUNCTION"
10017N/A>lwres_gabnrequest_free()</TT
10017N/A>
10017N/Arelease the memory in resolver context
15153N/A<TT
10017N/ACLASS="PARAMETER"
10017N/A><I
10017N/A>ctx</I
10017N/A></TT
15153N/A>
15153N/Athat was allocated to the
15153N/A<SPAN
15153N/ACLASS="TYPE"
10017N/A>lwres_gabnresponse_t</SPAN
10017N/A>
10017N/Aor
10017N/A<SPAN
10017N/ACLASS="TYPE"
10017N/A>lwres_gabnrequest_t</SPAN
10017N/A>
10017N/Astructures referenced via
10017N/A<TT
10017N/ACLASS="PARAMETER"
10017N/A><I
15153N/A>structp</I
15153N/A></TT
10017N/A>.
10017N/A
10017N/AAny memory associated with ancillary buffers and strings for those
10017N/Astructures is also discarded.</P
10017N/A></DIV
10017N/A><DIV
10017N/ACLASS="REFSECT1"
10017N/A><A
15153N/ANAME="AEN93"
10017N/A></A
10017N/A><H2
10017N/A>RETURN VALUES</H2
10017N/A><P
10017N/A>The getaddrbyname opcode functions
10017N/A<TT
15153N/ACLASS="FUNCTION"
10017N/A>lwres_gabnrequest_render()</TT
10017N/A>,
10017N/A<TT
15153N/ACLASS="FUNCTION"
15153N/A>lwres_gabnresponse_render()</TT
15153N/A>
10017N/A<TT
15153N/ACLASS="FUNCTION"
15153N/A>lwres_gabnrequest_parse()</TT
15153N/A>
15153N/Aand
15153N/A<TT
15153N/ACLASS="FUNCTION"
15153N/A>lwres_gabnresponse_parse()</TT
10017N/A>
10017N/Aall return
15153N/A<SPAN
15153N/ACLASS="ERRORCODE"
10017N/A>LWRES_R_SUCCESS</SPAN
10017N/A>
10017N/Aon success.
15153N/AThey return
15153N/A<SPAN
15153N/ACLASS="ERRORCODE"
15153N/A>LWRES_R_NOMEMORY</SPAN
15153N/A>
15153N/Aif memory allocation fails.
15153N/A<SPAN
15153N/ACLASS="ERRORCODE"
15153N/A>LWRES_R_UNEXPECTEDEND</SPAN
15153N/A>
15153N/Ais returned if the available space in the buffer
15153N/A<TT
15153N/ACLASS="PARAMETER"
15153N/A><I
15153N/A>b</I
15153N/A></TT
15153N/A>
15153N/Ais too small to accommodate the packet header or the
10017N/A<SPAN
10017N/ACLASS="TYPE"
10017N/A>lwres_gabnrequest_t</SPAN
15153N/A>
15153N/Aand
15153N/A<SPAN
10017N/ACLASS="TYPE"
10017N/A>lwres_gabnresponse_t</SPAN
10017N/A>
15153N/Astructures.
15153N/A<TT
15153N/ACLASS="FUNCTION"
15153N/A>lwres_gabnrequest_parse()</TT
15153N/A>
15153N/Aand
15153N/A<TT
15153N/ACLASS="FUNCTION"
15153N/A>lwres_gabnresponse_parse()</TT
15153N/A>
10017N/Awill return
10017N/A<SPAN
10017N/ACLASS="ERRORCODE"
15153N/A>LWRES_R_UNEXPECTEDEND</SPAN
15153N/A>
10017N/Aif the buffer is not empty after decoding the received packet.
10017N/AThese functions will return
10017N/A<SPAN
15153N/ACLASS="ERRORCODE"
15153N/A>LWRES_R_FAILURE</SPAN
15153N/A>
15153N/Aif
15153N/A<TT
15153N/ACLASS="STRUCTFIELD"
15153N/A><I
15153N/A>pktflags</I
15153N/A></TT
10017N/A>
10017N/Ain the packet header structure
15153N/A<SPAN
15153N/ACLASS="TYPE"
15153N/A>lwres_lwpacket_t</SPAN
10017N/A>
10017N/Aindicate that the packet is not a response to an earlier query.</P
10017N/A></DIV
15153N/A><DIV
15153N/ACLASS="REFSECT1"
15153N/A><A
15153N/ANAME="AEN112"
15153N/A></A
15153N/A><H2
15153N/A>SEE ALSO</H2
15153N/A><P
15153N/A><SPAN
15153N/ACLASS="CITEREFENTRY"
15153N/A><SPAN
15153N/ACLASS="REFENTRYTITLE"
15153N/A>lwres_packet</SPAN
15153N/A>(3)</SPAN
15153N/A></P
15153N/A></DIV
15153N/A></BODY
15153N/A></HTML
15153N/A>
15153N/A