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59 lines
2.4 KiB
59 lines
2.4 KiB
<?xml version="1.0" encoding="UTF-8"?>
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<!DOCTYPE section PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
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"http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
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<section id="to_parser" xmlns:xi="http://www.w3.org/2001/XInclude">
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<sectioninfo>
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<revhistory>
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<revision>
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<revnumber>$Revision$</revnumber>
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<date>$Date$</date>
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</revision>
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</revhistory>
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</sectioninfo>
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<title>To Header Field Parser</title>
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<para>
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Purpose of this parser is to parse body of To header field. The parser
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can be found in file <filename>parse_to.c</filename> under
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<filename>parser</filename> subdirectory.
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</para>
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<para>
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Main function is <function>parse_to</function> but there is no need to
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call the function explicitly. Every time the parser finds a To header
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field, this function will be called automatically. Result of the parser
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is <structname>to_body</structname> structure. Pointer to the structure
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will be stored in <structfield>parsed</structfield> field of
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<structname>hdr_field</structname> structure. Since the pointer is
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<type>void*</type>, there is a convenience macro
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<function>get_to</function> in file <filename>parse_to.h</filename>
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that will do the necessary type-casting and will return pointer to
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<structname>to_body</structname> structure.
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</para>
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<para>
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The parser itself is a finite state machine that will parse To body
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according to the grammar defined in <acronym>RFC3261</acronym> and
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store result in <structname>to_body</structname> structure.
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</para>
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<para>
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The parser gets called automatically from function
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<function>get_hdr_field</function> in file
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<filename>msg_parser.c</filename>. The function first creates and
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initializes an instance of <structname>to_body</structname> structure,
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then calls <function>parse_to</function> function with the structure as
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a parameter and if everything went OK, puts the pointer to the
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structure in <structfield>parsed</structfield> field of
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<structname>hdr_field</structname> structure representing the parsed To
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header field.
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</para>
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<para>
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The newly created structure will be freed when the message is being
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destroyed, see function <function>clean_hdr_field</function> in file
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<filename>hf.c</filename> for more details.
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</para>
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<para>
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See <xref linkend="to_body"/> for detailed description of the data
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structure produced by this parser.
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</para>
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</section>
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