kamailio/doc/tutorials/serdev/msg_start.xml

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<!DOCTYPE section PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN" 
   "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">

<section id="msg_start" xmlns:xi="http://www.w3.org/2001/XInclude">
    <sectioninfo>
	<revhistory>
	    <revision>
		<revnumber>$Revision$</revnumber>
		<date>$Date$</date>
	    </revision>
	</revhistory>
    </sectioninfo>

    <title>Structure <structname>msg_start</structname></title>
    <para>
	The structure represents the first line of a <acronym>SIP</acronym>
	request or response.
    </para>
    <para>
	The structure is defined in file <filename>parse_fline.h</filename>
	under <filename>parser</filename> subdirectory.
    </para>
    
    <para>
	<emphasis>Structure Declaration</emphasis>
	<programlisting>
struct msg_start {
    int type;                        /* Type of the Message - Request/Response */
    union {
        struct {
            str method;              /* Method string */
            str uri;                 /* Request URI */
            str version;             /* SIP version */
            int method_value;        /* Parsed method */
        } request;

        struct {
            str version;             /* SIP version */
            str status;              /* Reply status */
            str reason;              /* Reply reason phrase */
            unsigned int statuscode; /* Status code */
        } reply;
    }u;
};
	</programlisting>
    </para>
    <para>
	<emphasis>Description of Request Related Fields:</emphasis>
	<itemizedlist>
	    <listitem>
		<para>
		    <structfield>type</structfield> - Type of the message -
		    REQUEST or RESPONSE.
		</para>
	    </listitem>
	    <listitem>
		<para>
		    <structfield>method</structfield> - Name of method (same as
		    in the message).
		</para>
	    </listitem>
	    <listitem>
		<para>
		    <structfield>uri</structfield> - Request <acronym>URI</acronym>.
		</para>
	    </listitem>
	    <listitem>
		<para>
		    <structfield>version</structfield> - Version string.
		</para>
	    </listitem>
	    <listitem>
		<para>
		    <structfield>method_value</structfield> - Parsed
		    method. Field method which is of type <type>str</type> will
		    be converted to integer and stored here. This is good for
		    comparison, integer comparison is much faster then string
		    comparison.
		</para>
	    </listitem>
	</itemizedlist>
    </para>

    <para>
	<emphasis>Description of Response Related Fields:</emphasis>
	<itemizedlist>
	    <listitem>
		<para>
		    <structfield>version</structfield> - Version string.
		</para>
	    </listitem>
	    <listitem>
		<para>
		    <structfield>status</structfield> - Response status code as
		    string.
		</para>
	    </listitem>
	    <listitem>
		<para>
		    <structfield>reason</structfield> - Response reason string
		    as in the message.
		</para>
	    </listitem>
	    <listitem>
		<para>
		    <structfield>statuscode</structfield> - Response status
		    code converted to integer.
		</para>
	    </listitem>
	</itemizedlist>
    </para>
</section>