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      5  1.1  tron <head>
      6  1.1  tron <!-- Copyright 1999,2000 Clark Cooper <coopercc (a] netheaven.com>
      7  1.1  tron      All rights reserved.
      8  1.1  tron      This is free software. You may distribute or modify according to
      9  1.1  tron      the terms of the MIT/X License -->
     10  1.1  tron   <title>Expat XML Parser</title>
     11  1.1  tron   <meta name="author" content="Clark Cooper, coopercc (a] netheaven.com" />
     12  1.1  tron   <meta http-equiv="Content-Style-Type" content="text/css" />
     13  1.1  tron   <link href="style.css" rel="stylesheet" type="text/css" />
     14  1.1  tron </head>
     15  1.1  tron <body>
     16  1.1  tron   <table cellspacing="0" cellpadding="0" width="100%">
     17  1.1  tron     <tr>
     18  1.1  tron       <td class="corner"><img src="expat.png" alt="(Expat logo)" /></td>
     19  1.1  tron       <td class="banner"><h1>The Expat XML Parser</h1></td>
     20  1.1  tron     </tr>
     21  1.1  tron     <tr>
     22  1.1  tron       <td class="releaseno">Release 2.0.1</td>
     23  1.1  tron       <td></td>
     24  1.1  tron     </tr>
     25  1.1  tron   </table>
     26  1.1  tron <div class="content">
     27  1.1  tron 
     28  1.1  tron <p>Expat is a library, written in C, for parsing XML documents. It's
     29  1.1  tron the underlying XML parser for the open source Mozilla project, Perl's
     30  1.1  tron <code>XML::Parser</code>, Python's <code>xml.parsers.expat</code>, and
     31  1.1  tron other open-source XML parsers.</p>
     32  1.1  tron 
     33  1.1  tron <p>This library is the creation of James Clark, who's also given us
     34  1.1  tron groff (an nroff look-alike), Jade (an implemention of ISO's DSSSL
     35  1.1  tron stylesheet language for SGML), XP (a Java XML parser package), XT (a
     36  1.1  tron Java XSL engine).  James was also the technical lead on the XML
     37  1.1  tron Working Group at W3C that produced the XML specification.</p>
     38  1.1  tron 
     39  1.1  tron <p>This is free software, licensed under the <a
     40  1.1  tron href="../COPYING">MIT/X Consortium license</a>. You may download it
     41  1.1  tron from <a href="http://www.libexpat.org/">the Expat home page</a>.
     42  1.1  tron </p>
     43  1.1  tron 
     44  1.1  tron <p>The bulk of this document was originally commissioned as an article
     45  1.1  tron by <a href="http://www.xml.com/">XML.com</a>. They graciously allowed
     46  1.1  tron Clark Cooper to retain copyright and to distribute it with Expat.
     47  1.1  tron This version has been substantially extended to include documentation
     48  1.1  tron on features which have been added since the original article was
     49  1.1  tron published, and additional information on using the original
     50  1.1  tron interface.</p>
     51  1.1  tron 
     52  1.1  tron <hr />
     53  1.1  tron <h2>Table of Contents</h2>
     54  1.1  tron <ul>
     55  1.1  tron   <li><a href="#overview">Overview</a></li>
     56  1.1  tron   <li><a href="#building">Building and Installing</a></li>
     57  1.1  tron   <li><a href="#using">Using Expat</a></li>
     58  1.1  tron   <li><a href="#reference">Reference</a>
     59  1.1  tron   <ul>
     60  1.1  tron     <li><a href="#creation">Parser Creation Functions</a>
     61  1.1  tron     <ul>
     62  1.1  tron       <li><a href="#XML_ParserCreate">XML_ParserCreate</a></li>
     63  1.1  tron       <li><a href="#XML_ParserCreateNS">XML_ParserCreateNS</a></li>
     64  1.1  tron       <li><a href="#XML_ParserCreate_MM">XML_ParserCreate_MM</a></li>
     65  1.1  tron       <li><a href="#XML_ExternalEntityParserCreate">XML_ExternalEntityParserCreate</a></li>
     66  1.1  tron       <li><a href="#XML_ParserFree">XML_ParserFree</a></li>
     67  1.1  tron       <li><a href="#XML_ParserReset">XML_ParserReset</a></li>
     68  1.1  tron     </ul>
     69  1.1  tron     </li>
     70  1.1  tron     <li><a href="#parsing">Parsing Functions</a>
     71  1.1  tron     <ul>
     72  1.1  tron       <li><a href="#XML_Parse">XML_Parse</a></li>
     73  1.1  tron       <li><a href="#XML_ParseBuffer">XML_ParseBuffer</a></li>
     74  1.1  tron       <li><a href="#XML_GetBuffer">XML_GetBuffer</a></li>
     75  1.1  tron       <li><a href="#XML_StopParser">XML_StopParser</a></li>
     76  1.1  tron       <li><a href="#XML_ResumeParser">XML_ResumeParser</a></li>
     77  1.1  tron       <li><a href="#XML_GetParsingStatus">XML_GetParsingStatus</a></li>
     78  1.1  tron     </ul>
     79  1.1  tron     </li>
     80  1.1  tron     <li><a href="#setting">Handler Setting Functions</a>
     81  1.1  tron     <ul>
     82  1.1  tron       <li><a href="#XML_SetStartElementHandler">XML_SetStartElementHandler</a></li>
     83  1.1  tron       <li><a href="#XML_SetEndElementHandler">XML_SetEndElementHandler</a></li>
     84  1.1  tron       <li><a href="#XML_SetElementHandler">XML_SetElementHandler</a></li>
     85  1.1  tron       <li><a href="#XML_SetCharacterDataHandler">XML_SetCharacterDataHandler</a></li>
     86  1.1  tron       <li><a href="#XML_SetProcessingInstructionHandler">XML_SetProcessingInstructionHandler</a></li>
     87  1.1  tron       <li><a href="#XML_SetCommentHandler">XML_SetCommentHandler</a></li>
     88  1.1  tron       <li><a href="#XML_SetStartCdataSectionHandler">XML_SetStartCdataSectionHandler</a></li>
     89  1.1  tron       <li><a href="#XML_SetEndCdataSectionHandler">XML_SetEndCdataSectionHandler</a></li>
     90  1.1  tron       <li><a href="#XML_SetCdataSectionHandler">XML_SetCdataSectionHandler</a></li>
     91  1.1  tron       <li><a href="#XML_SetDefaultHandler">XML_SetDefaultHandler</a></li>
     92  1.1  tron       <li><a href="#XML_SetDefaultHandlerExpand">XML_SetDefaultHandlerExpand</a></li>
     93  1.1  tron       <li><a href="#XML_SetExternalEntityRefHandler">XML_SetExternalEntityRefHandler</a></li>
     94  1.1  tron       <li><a href="#XML_SetExternalEntityRefHandlerArg">XML_SetExternalEntityRefHandlerArg</a></li>
     95  1.1  tron       <li><a href="#XML_SetSkippedEntityHandler">XML_SetSkippedEntityHandler</a></li>
     96  1.1  tron       <li><a href="#XML_SetUnknownEncodingHandler">XML_SetUnknownEncodingHandler</a></li>
     97  1.1  tron       <li><a href="#XML_SetStartNamespaceDeclHandler">XML_SetStartNamespaceDeclHandler</a></li>
     98  1.1  tron       <li><a href="#XML_SetEndNamespaceDeclHandler">XML_SetEndNamespaceDeclHandler</a></li>
     99  1.1  tron       <li><a href="#XML_SetNamespaceDeclHandler">XML_SetNamespaceDeclHandler</a></li>
    100  1.1  tron       <li><a href="#XML_SetXmlDeclHandler">XML_SetXmlDeclHandler</a></li>		  
    101  1.1  tron       <li><a href="#XML_SetStartDoctypeDeclHandler">XML_SetStartDoctypeDeclHandler</a></li>
    102  1.1  tron       <li><a href="#XML_SetEndDoctypeDeclHandler">XML_SetEndDoctypeDeclHandler</a></li>
    103  1.1  tron       <li><a href="#XML_SetDoctypeDeclHandler">XML_SetDoctypeDeclHandler</a></li>
    104  1.1  tron       <li><a href="#XML_SetElementDeclHandler">XML_SetElementDeclHandler</a></li>
    105  1.1  tron       <li><a href="#XML_SetAttlistDeclHandler">XML_SetAttlistDeclHandler</a></li>
    106  1.1  tron       <li><a href="#XML_SetEntityDeclHandler">XML_SetEntityDeclHandler</a></li>
    107  1.1  tron       <li><a href="#XML_SetUnparsedEntityDeclHandler">XML_SetUnparsedEntityDeclHandler</a></li>
    108  1.1  tron       <li><a href="#XML_SetNotationDeclHandler">XML_SetNotationDeclHandler</a></li>
    109  1.1  tron       <li><a href="#XML_SetNotStandaloneHandler">XML_SetNotStandaloneHandler</a></li>
    110  1.1  tron     </ul>
    111  1.1  tron     </li>
    112  1.1  tron     <li><a href="#position">Parse Position and Error Reporting Functions</a>
    113  1.1  tron     <ul>
    114  1.1  tron       <li><a href="#XML_GetErrorCode">XML_GetErrorCode</a></li>
    115  1.1  tron       <li><a href="#XML_ErrorString">XML_ErrorString</a></li>
    116  1.1  tron       <li><a href="#XML_GetCurrentByteIndex">XML_GetCurrentByteIndex</a></li>
    117  1.1  tron       <li><a href="#XML_GetCurrentLineNumber">XML_GetCurrentLineNumber</a></li>
    118  1.1  tron       <li><a href="#XML_GetCurrentColumnNumber">XML_GetCurrentColumnNumber</a></li>
    119  1.1  tron       <li><a href="#XML_GetCurrentByteCount">XML_GetCurrentByteCount</a></li>
    120  1.1  tron       <li><a href="#XML_GetInputContext">XML_GetInputContext</a></li>
    121  1.1  tron     </ul>
    122  1.1  tron     </li>
    123  1.1  tron     <li><a href="#miscellaneous">Miscellaneous Functions</a>
    124  1.1  tron     <ul>
    125  1.1  tron       <li><a href="#XML_SetUserData">XML_SetUserData</a></li>
    126  1.1  tron       <li><a href="#XML_GetUserData">XML_GetUserData</a></li>
    127  1.1  tron       <li><a href="#XML_UseParserAsHandlerArg">XML_UseParserAsHandlerArg</a></li>
    128  1.1  tron       <li><a href="#XML_SetBase">XML_SetBase</a></li>
    129  1.1  tron       <li><a href="#XML_GetBase">XML_GetBase</a></li>
    130  1.1  tron       <li><a href="#XML_GetSpecifiedAttributeCount">XML_GetSpecifiedAttributeCount</a></li>
    131  1.1  tron       <li><a href="#XML_GetIdAttributeIndex">XML_GetIdAttributeIndex</a></li>
    132  1.1  tron       <li><a href="#XML_SetEncoding">XML_SetEncoding</a></li>
    133  1.1  tron       <li><a href="#XML_SetParamEntityParsing">XML_SetParamEntityParsing</a></li>
    134  1.1  tron       <li><a href="#XML_UseForeignDTD">XML_UseForeignDTD</a></li>
    135  1.1  tron       <li><a href="#XML_SetReturnNSTriplet">XML_SetReturnNSTriplet</a></li>
    136  1.1  tron       <li><a href="#XML_DefaultCurrent">XML_DefaultCurrent</a></li>
    137  1.1  tron       <li><a href="#XML_ExpatVersion">XML_ExpatVersion</a></li>
    138  1.1  tron       <li><a href="#XML_ExpatVersionInfo">XML_ExpatVersionInfo</a></li>
    139  1.1  tron       <li><a href="#XML_GetFeatureList">XML_GetFeatureList</a></li>
    140  1.1  tron       <li><a href="#XML_FreeContentModel">XML_FreeContentModel</a></li>
    141  1.1  tron       <li><a href="#XML_MemMalloc">XML_MemMalloc</a></li>
    142  1.1  tron       <li><a href="#XML_MemRealloc">XML_MemRealloc</a></li>
    143  1.1  tron       <li><a href="#XML_MemFree">XML_MemFree</a></li>
    144  1.1  tron     </ul>
    145  1.1  tron     </li>
    146  1.1  tron   </ul>  
    147  1.1  tron   </li>
    148  1.1  tron </ul>
    149  1.1  tron 
    150  1.1  tron <hr />
    151  1.1  tron <h2><a name="overview">Overview</a></h2>
    152  1.1  tron 
    153  1.1  tron <p>Expat is a stream-oriented parser. You register callback (or
    154  1.1  tron handler) functions with the parser and then start feeding it the
    155  1.1  tron document.  As the parser recognizes parts of the document, it will
    156  1.1  tron call the appropriate handler for that part (if you've registered one.) 
    157  1.1  tron The document is fed to the parser in pieces, so you can start parsing
    158  1.1  tron before you have all the document. This also allows you to parse really
    159  1.1  tron huge documents that won't fit into memory.</p>
    160  1.1  tron 
    161  1.1  tron <p>Expat can be intimidating due to the many kinds of handlers and
    162  1.1  tron options you can set. But you only need to learn four functions in
    163  1.1  tron order to do 90% of what you'll want to do with it:</p>
    164  1.1  tron 
    165  1.1  tron <dl>
    166  1.1  tron 
    167  1.1  tron <dt><code><a href= "#XML_ParserCreate"
    168  1.1  tron              >XML_ParserCreate</a></code></dt>
    169  1.1  tron   <dd>Create a new parser object.</dd>
    170  1.1  tron 
    171  1.1  tron <dt><code><a href= "#XML_SetElementHandler"
    172  1.1  tron              >XML_SetElementHandler</a></code></dt>
    173  1.1  tron   <dd>Set handlers for start and end tags.</dd>
    174  1.1  tron 
    175  1.1  tron <dt><code><a href= "#XML_SetCharacterDataHandler"
    176  1.1  tron              >XML_SetCharacterDataHandler</a></code></dt>
    177  1.1  tron   <dd>Set handler for text.</dd>
    178  1.1  tron 
    179  1.1  tron <dt><code><a href= "#XML_Parse"
    180  1.1  tron              >XML_Parse</a></code></dt>
    181  1.1  tron   <dd>Pass a buffer full of document to the parser</dd>
    182  1.1  tron </dl>
    183  1.1  tron 
    184  1.1  tron <p>These functions and others are described in the <a
    185  1.1  tron href="#reference">reference</a> part of this document. The reference
    186  1.1  tron section also describes in detail the parameters passed to the
    187  1.1  tron different types of handlers.</p>
    188  1.1  tron 
    189  1.1  tron <p>Let's look at a very simple example program that only uses 3 of the
    190  1.1  tron above functions (it doesn't need to set a character handler.) The
    191  1.1  tron program <a href="../examples/outline.c">outline.c</a> prints an
    192  1.1  tron element outline, indenting child elements to distinguish them from the
    193  1.1  tron parent element that contains them. The start handler does all the
    194  1.1  tron work.  It prints two indenting spaces for every level of ancestor
    195  1.1  tron elements, then it prints the element and attribute
    196  1.1  tron information. Finally it increments the global <code>Depth</code>
    197  1.1  tron variable.</p>
    198  1.1  tron 
    199  1.1  tron <pre class="eg">
    200  1.1  tron int Depth;
    201  1.1  tron 
    202  1.1  tron void XMLCALL
    203  1.1  tron start(void *data, const char *el, const char **attr) {
    204  1.1  tron   int i;
    205  1.1  tron 
    206  1.1  tron   for (i = 0; i &lt; Depth; i++)
    207  1.1  tron     printf("  ");
    208  1.1  tron 
    209  1.1  tron   printf("%s", el);
    210  1.1  tron 
    211  1.1  tron   for (i = 0; attr[i]; i += 2) {
    212  1.1  tron     printf(" %s='%s'", attr[i], attr[i + 1]);
    213  1.1  tron   }
    214  1.1  tron 
    215  1.1  tron   printf("\n");
    216  1.1  tron   Depth++;
    217  1.1  tron }  /* End of start handler */
    218  1.1  tron </pre>
    219  1.1  tron 
    220  1.1  tron <p>The end tag simply does the bookkeeping work of decrementing
    221  1.1  tron <code>Depth</code>.</p>
    222  1.1  tron <pre class="eg">
    223  1.1  tron void XMLCALL
    224  1.1  tron end(void *data, const char *el) {
    225  1.1  tron   Depth--;
    226  1.1  tron }  /* End of end handler */
    227  1.1  tron </pre>
    228  1.1  tron 
    229  1.1  tron <p>Note the <code>XMLCALL</code> annotation used for the callbacks.
    230  1.1  tron This is used to ensure that the Expat and the callbacks are using the
    231  1.1  tron same calling convention in case the compiler options used for Expat
    232  1.1  tron itself and the client code are different.  Expat tries not to care
    233  1.1  tron what the default calling convention is, though it may require that it
    234  1.1  tron be compiled with a default convention of "cdecl" on some platforms.
    235  1.1  tron For code which uses Expat, however, the calling convention is
    236  1.1  tron specified by the <code>XMLCALL</code> annotation on most platforms;
    237  1.1  tron callbacks should be defined using this annotation.</p>
    238  1.1  tron 
    239  1.1  tron <p>The <code>XMLCALL</code> annotation was added in Expat 1.95.7, but
    240  1.1  tron existing working Expat applications don't need to add it (since they
    241  1.1  tron are already using the "cdecl" calling convention, or they wouldn't be
    242  1.1  tron working).  The annotation is only needed if the default calling
    243  1.1  tron convention may be something other than "cdecl".  To use the annotation
    244  1.1  tron safely with older versions of Expat, you can conditionally define it
    245  1.1  tron <em>after</em> including Expat's header file:</p>
    246  1.1  tron 
    247  1.1  tron <pre class="eg">
    248  1.1  tron #include &lt;expat.h&gt;
    249  1.1  tron 
    250  1.1  tron #ifndef XMLCALL
    251  1.1  tron #if defined(_MSC_EXTENSIONS) &amp;&amp; !defined(__BEOS__) &amp;&amp; !defined(__CYGWIN__)
    252  1.1  tron #define XMLCALL __cdecl
    253  1.1  tron #elif defined(__GNUC__)
    254  1.1  tron #define XMLCALL __attribute__((cdecl))
    255  1.1  tron #else
    256  1.1  tron #define XMLCALL
    257  1.1  tron #endif
    258  1.1  tron #endif
    259  1.1  tron </pre>
    260  1.1  tron 
    261  1.1  tron <p>After creating the parser, the main program just has the job of
    262  1.1  tron shoveling the document to the parser so that it can do its work.</p>
    263  1.1  tron 
    264  1.1  tron <hr />
    265  1.1  tron <h2><a name="building">Building and Installing Expat</a></h2>
    266  1.1  tron 
    267  1.1  tron <p>The Expat distribution comes as a compressed (with GNU gzip) tar
    268  1.1  tron file.  You may download the latest version from <a href=
    269  1.1  tron "http://sourceforge.net/projects/expat/" >Source Forge</a>.  After
    270  1.1  tron unpacking this, cd into the directory. Then follow either the Win32
    271  1.1  tron directions or Unix directions below.</p>
    272  1.1  tron 
    273  1.1  tron <h3>Building under Win32</h3>
    274  1.1  tron 
    275  1.1  tron <p>If you're using the GNU compiler under cygwin, follow the Unix
    276  1.1  tron directions in the next section. Otherwise if you have Microsoft's
    277  1.1  tron Developer Studio installed, then from Windows Explorer double-click on
    278  1.1  tron "expat.dsp" in the lib directory and build and install in the usual
    279  1.1  tron manner.</p>
    280  1.1  tron 
    281  1.1  tron <p>Alternatively, you may download the Win32 binary package that
    282  1.1  tron contains the "expat.h" include file and a pre-built DLL.</p>
    283  1.1  tron 
    284  1.1  tron <h3>Building under Unix (or GNU)</h3>
    285  1.1  tron 
    286  1.1  tron <p>First you'll need to run the configure shell script in order to
    287  1.1  tron configure the Makefiles and headers for your system.</p>
    288  1.1  tron 
    289  1.1  tron <p>If you're happy with all the defaults that configure picks for you,
    290  1.1  tron and you have permission on your system to install into /usr/local, you
    291  1.1  tron can install Expat with this sequence of commands:</p>
    292  1.1  tron 
    293  1.1  tron <pre class="eg">
    294  1.1  tron ./configure
    295  1.1  tron make
    296  1.1  tron make install
    297  1.1  tron </pre>
    298  1.1  tron 
    299  1.1  tron <p>There are some options that you can provide to this script, but the
    300  1.1  tron only one we'll mention here is the <code>--prefix</code> option. You
    301  1.1  tron can find out all the options available by running configure with just
    302  1.1  tron the <code>--help</code> option.</p>
    303  1.1  tron 
    304  1.1  tron <p>By default, the configure script sets things up so that the library
    305  1.1  tron gets installed in <code>/usr/local/lib</code> and the associated
    306  1.1  tron header file in <code>/usr/local/include</code>.  But if you were to
    307  1.1  tron give the option, <code>--prefix=/home/me/mystuff</code>, then the
    308  1.1  tron library and header would get installed in
    309  1.1  tron <code>/home/me/mystuff/lib</code> and
    310  1.1  tron <code>/home/me/mystuff/include</code> respectively.</p>
    311  1.1  tron 
    312  1.1  tron <h3>Configuring Expat Using the Pre-Processor</h3>
    313  1.1  tron 
    314  1.1  tron <p>Expat's feature set can be configured using a small number of
    315  1.1  tron pre-processor definitions.  The definition of this symbols does not
    316  1.1  tron affect the set of entry points for Expat, only the behavior of the API
    317  1.1  tron and the definition of character types in the case of
    318  1.1  tron <code>XML_UNICODE_WCHAR_T</code>.  The symbols are:</p>
    319  1.1  tron 
    320  1.1  tron <dl class="cpp-symbols">
    321  1.1  tron <dt>XML_DTD</dt>
    322  1.1  tron <dd>Include support for using and reporting DTD-based content.  If
    323  1.1  tron this is defined, default attribute values from an external DTD subset
    324  1.1  tron are reported and attribute value normalization occurs based on the
    325  1.1  tron type of attributes defined in the external subset.  Without
    326  1.1  tron this, Expat has a smaller memory footprint and can be faster, but will
    327  1.1  tron not load external entities or process conditional sections.  This does
    328  1.1  tron not affect the set of functions available in the API.</dd>
    329  1.1  tron 
    330  1.1  tron <dt>XML_NS</dt>
    331  1.1  tron <dd>When defined, support for the <cite><a href=
    332  1.1  tron "http://www.w3.org/TR/REC-xml-names/" >Namespaces in XML</a></cite>
    333  1.1  tron specification is included.</dd>
    334  1.1  tron 
    335  1.1  tron <dt>XML_UNICODE</dt>
    336  1.1  tron <dd>When defined, character data reported to the application is
    337  1.1  tron encoded in UTF-16 using wide characters of the type
    338  1.1  tron <code>XML_Char</code>.  This is implied if
    339  1.1  tron <code>XML_UNICODE_WCHAR_T</code> is defined.</dd>
    340  1.1  tron 
    341  1.1  tron <dt>XML_UNICODE_WCHAR_T</dt>
    342  1.1  tron <dd>If defined, causes the <code>XML_Char</code> character type to be
    343  1.1  tron defined using the <code>wchar_t</code> type; otherwise, <code>unsigned
    344  1.1  tron short</code> is used.  Defining this implies
    345  1.1  tron <code>XML_UNICODE</code>.</dd>
    346  1.1  tron 
    347  1.1  tron <dt>XML_LARGE_SIZE</dt>
    348  1.1  tron <dd>If defined, causes the <code>XML_Size</code> and <code>XML_Index</code>
    349  1.1  tron integer types to be at least 64 bits in size. This is intended to support
    350  1.1  tron processing of very large input streams, where the return values of
    351  1.1  tron <code><a href="#XML_GetCurrentByteIndex" >XML_GetCurrentByteIndex</a></code>,
    352  1.1  tron <code><a href="#XML_GetCurrentLineNumber" >XML_GetCurrentLineNumber</a></code> and
    353  1.1  tron <code><a href="#XML_GetCurrentColumnNumber" >XML_GetCurrentColumnNumber</a></code>
    354  1.1  tron could overflow. It may not be supported by all compilers, and is turned
    355  1.1  tron off by default.</dd>
    356  1.1  tron 
    357  1.1  tron <dt>XML_CONTEXT_BYTES</dt>
    358  1.1  tron <dd>The number of input bytes of markup context which the parser will
    359  1.1  tron ensure are available for reporting via <code><a href=
    360  1.1  tron "#XML_GetInputContext" >XML_GetInputContext</a></code>.  This is
    361  1.1  tron normally set to 1024, and must be set to a positive interger.  If this
    362  1.1  tron is not defined, the input context will not be available and <code><a
    363  1.1  tron href= "#XML_GetInputContext" >XML_GetInputContext</a></code> will
    364  1.1  tron always report NULL.  Without this, Expat has a smaller memory
    365  1.1  tron footprint and can be faster.</dd>
    366  1.1  tron 
    367  1.1  tron <dt>XML_STATIC</dt>
    368  1.1  tron <dd>On Windows, this should be set if Expat is going to be linked
    369  1.1  tron statically with the code that calls it; this is required to get all
    370  1.1  tron the right MSVC magic annotations correct.  This is ignored on other
    371  1.1  tron platforms.</dd>
    372  1.1  tron </dl>
    373  1.1  tron 
    374  1.1  tron <hr />
    375  1.1  tron <h2><a name="using">Using Expat</a></h2>
    376  1.1  tron 
    377  1.1  tron <h3>Compiling and Linking Against Expat</h3>
    378  1.1  tron 
    379  1.1  tron <p>Unless you installed Expat in a location not expected by your
    380  1.1  tron compiler and linker, all you have to do to use Expat in your programs
    381  1.1  tron is to include the Expat header (<code>#include &lt;expat.h&gt;</code>)
    382  1.1  tron in your files that make calls to it and to tell the linker that it
    383  1.1  tron needs to link against the Expat library.  On Unix systems, this would
    384  1.1  tron usually be done with the <code>-lexpat</code> argument.  Otherwise,
    385  1.1  tron you'll need to tell the compiler where to look for the Expat header
    386  1.1  tron and the linker where to find the Expat library.  You may also need to
    387  1.1  tron take steps to tell the operating system where to find this library at
    388  1.1  tron run time.</p>
    389  1.1  tron 
    390  1.1  tron <p>On a Unix-based system, here's what a Makefile might look like when
    391  1.1  tron Expat is installed in a standard location:</p>
    392  1.1  tron 
    393  1.1  tron <pre class="eg">
    394  1.1  tron CC=cc
    395  1.1  tron LDFLAGS=
    396  1.1  tron LIBS= -lexpat
    397  1.1  tron xmlapp: xmlapp.o
    398  1.1  tron         $(CC) $(LDFLAGS) -o xmlapp xmlapp.o $(LIBS)
    399  1.1  tron </pre>
    400  1.1  tron 
    401  1.1  tron <p>If you installed Expat in, say, <code>/home/me/mystuff</code>, then
    402  1.1  tron the Makefile would look like this:</p>
    403  1.1  tron 
    404  1.1  tron <pre class="eg">
    405  1.1  tron CC=cc
    406  1.1  tron CFLAGS= -I/home/me/mystuff/include
    407  1.1  tron LDFLAGS=
    408  1.1  tron LIBS= -L/home/me/mystuff/lib -lexpat
    409  1.1  tron xmlapp: xmlapp.o
    410  1.1  tron         $(CC) $(LDFLAGS) -o xmlapp xmlapp.o $(LIBS)
    411  1.1  tron </pre>
    412  1.1  tron 
    413  1.1  tron <p>You'd also have to set the environment variable
    414  1.1  tron <code>LD_LIBRARY_PATH</code> to <code>/home/me/mystuff/lib</code> (or
    415  1.1  tron to <code>${LD_LIBRARY_PATH}:/home/me/mystuff/lib</code> if
    416  1.1  tron LD_LIBRARY_PATH already has some directories in it) in order to run
    417  1.1  tron your application.</p>
    418  1.1  tron 
    419  1.1  tron <h3>Expat Basics</h3>
    420  1.1  tron 
    421  1.1  tron <p>As we saw in the example in the overview, the first step in parsing
    422  1.1  tron an XML document with Expat is to create a parser object. There are <a
    423  1.1  tron href="#creation">three functions</a> in the Expat API for creating a
    424  1.1  tron parser object.  However, only two of these (<code><a href=
    425  1.1  tron "#XML_ParserCreate" >XML_ParserCreate</a></code> and <code><a href=
    426  1.1  tron "#XML_ParserCreateNS" >XML_ParserCreateNS</a></code>) can be used for
    427  1.1  tron constructing a parser for a top-level document.  The object returned
    428  1.1  tron by these functions is an opaque pointer (i.e. "expat.h" declares it as
    429  1.1  tron void *) to data with further internal structure. In order to free the
    430  1.1  tron memory associated with this object you must call <code><a href=
    431  1.1  tron "#XML_ParserFree" >XML_ParserFree</a></code>. Note that if you have
    432  1.1  tron provided any <a href="#userdata">user data</a> that gets stored in the
    433  1.1  tron parser, then your application is responsible for freeing it prior to
    434  1.1  tron calling <code>XML_ParserFree</code>.</p>
    435  1.1  tron 
    436  1.1  tron <p>The objects returned by the parser creation functions are good for
    437  1.1  tron parsing only one XML document or external parsed entity. If your
    438  1.1  tron application needs to parse many XML documents, then it needs to create
    439  1.1  tron a parser object for each one. The best way to deal with this is to
    440  1.1  tron create a higher level object that contains all the default
    441  1.1  tron initialization you want for your parser objects.</p>
    442  1.1  tron 
    443  1.1  tron <p>Walking through a document hierarchy with a stream oriented parser
    444  1.1  tron will require a good stack mechanism in order to keep track of current
    445  1.1  tron context.  For instance, to answer the simple question, "What element
    446  1.1  tron does this text belong to?" requires a stack, since the parser may have
    447  1.1  tron descended into other elements that are children of the current one and
    448  1.1  tron has encountered this text on the way out.</p>
    449  1.1  tron 
    450  1.1  tron <p>The things you're likely to want to keep on a stack are the
    451  1.1  tron currently opened element and it's attributes. You push this
    452  1.1  tron information onto the stack in the start handler and you pop it off in
    453  1.1  tron the end handler.</p>
    454  1.1  tron 
    455  1.1  tron <p>For some tasks, it is sufficient to just keep information on what
    456  1.1  tron the depth of the stack is (or would be if you had one.) The outline
    457  1.1  tron program shown above presents one example. Another such task would be
    458  1.1  tron skipping over a complete element. When you see the start tag for the
    459  1.1  tron element you want to skip, you set a skip flag and record the depth at
    460  1.1  tron which the element started.  When the end tag handler encounters the
    461  1.1  tron same depth, the skipped element has ended and the flag may be
    462  1.1  tron cleared. If you follow the convention that the root element starts at
    463  1.1  tron 1, then you can use the same variable for skip flag and skip
    464  1.1  tron depth.</p>
    465  1.1  tron 
    466  1.1  tron <pre class="eg">
    467  1.1  tron void
    468  1.1  tron init_info(Parseinfo *info) {
    469  1.1  tron   info->skip = 0;
    470  1.1  tron   info->depth = 1;
    471  1.1  tron   /* Other initializations here */
    472  1.1  tron }  /* End of init_info */
    473  1.1  tron 
    474  1.1  tron void XMLCALL
    475  1.1  tron rawstart(void *data, const char *el, const char **attr) {
    476  1.1  tron   Parseinfo *inf = (Parseinfo *) data;
    477  1.1  tron 
    478  1.1  tron   if (! inf->skip) {
    479  1.1  tron     if (should_skip(inf, el, attr)) {
    480  1.1  tron       inf->skip = inf->depth;
    481  1.1  tron     }
    482  1.1  tron     else
    483  1.1  tron       start(inf, el, attr);     /* This does rest of start handling */
    484  1.1  tron   }
    485  1.1  tron 
    486  1.1  tron   inf->depth++;
    487  1.1  tron }  /* End of rawstart */
    488  1.1  tron 
    489  1.1  tron void XMLCALL
    490  1.1  tron rawend(void *data, const char *el) {
    491  1.1  tron   Parseinfo *inf = (Parseinfo *) data;
    492  1.1  tron 
    493  1.1  tron   inf->depth--;
    494  1.1  tron 
    495  1.1  tron   if (! inf->skip)
    496  1.1  tron     end(inf, el);              /* This does rest of end handling */
    497  1.1  tron 
    498  1.1  tron   if (inf->skip == inf->depth)
    499  1.1  tron     inf->skip = 0;
    500  1.1  tron }  /* End rawend */
    501  1.1  tron </pre>
    502  1.1  tron 
    503  1.1  tron <p>Notice in the above example the difference in how depth is
    504  1.1  tron manipulated in the start and end handlers. The end tag handler should
    505  1.1  tron be the mirror image of the start tag handler. This is necessary to
    506  1.1  tron properly model containment. Since, in the start tag handler, we
    507  1.1  tron incremented depth <em>after</em> the main body of start tag code, then
    508  1.1  tron in the end handler, we need to manipulate it <em>before</em> the main
    509  1.1  tron body.  If we'd decided to increment it first thing in the start
    510  1.1  tron handler, then we'd have had to decrement it last thing in the end
    511  1.1  tron handler.</p>
    512  1.1  tron 
    513  1.1  tron <h3 id="userdata">Communicating between handlers</h3>
    514  1.1  tron 
    515  1.1  tron <p>In order to be able to pass information between different handlers
    516  1.1  tron without using globals, you'll need to define a data structure to hold
    517  1.1  tron the shared variables. You can then tell Expat (with the <code><a href=
    518  1.1  tron "#XML_SetUserData" >XML_SetUserData</a></code> function) to pass a
    519  1.1  tron pointer to this structure to the handlers.  This is the first
    520  1.1  tron argument received by most handlers.  In the <a href="#reference"
    521  1.1  tron >reference section</a>, an argument to a callback function is named
    522  1.1  tron <code>userData</code> and have type <code>void *</code> if the user
    523  1.1  tron data is passed; it will have the type <code>XML_Parser</code> if the
    524  1.1  tron parser itself is passed.  When the parser is passed, the user data may
    525  1.1  tron be retrieved using <code><a href="#XML_GetUserData"
    526  1.1  tron >XML_GetUserData</a></code>.</p>
    527  1.1  tron 
    528  1.1  tron <p>One common case where multiple calls to a single handler may need
    529  1.1  tron to communicate using an application data structure is the case when
    530  1.1  tron content passed to the character data handler (set by <code><a href=
    531  1.1  tron "#XML_SetCharacterDataHandler"
    532  1.1  tron >XML_SetCharacterDataHandler</a></code>) needs to be accumulated.  A
    533  1.1  tron common first-time mistake with any of the event-oriented interfaces to
    534  1.1  tron an XML parser is to expect all the text contained in an element to be
    535  1.1  tron reported by a single call to the character data handler.  Expat, like
    536  1.1  tron many other XML parsers, reports such data as a sequence of calls;
    537  1.1  tron there's no way to know when the end of the sequence is reached until a
    538  1.1  tron different callback is made.  A buffer referenced by the user data
    539  1.1  tron structure proves both an effective and convenient place to accumulate
    540  1.1  tron character data.</p>
    541  1.1  tron 
    542  1.1  tron <!-- XXX example needed here -->
    543  1.1  tron 
    544  1.1  tron 
    545  1.1  tron <h3>XML Version</h3>
    546  1.1  tron 
    547  1.1  tron <p>Expat is an XML 1.0 parser, and as such never complains based on
    548  1.1  tron the value of the <code>version</code> pseudo-attribute in the XML
    549  1.1  tron declaration, if present.</p>
    550  1.1  tron 
    551  1.1  tron <p>If an application needs to check the version number (to support
    552  1.1  tron alternate processing), it should use the <code><a href=
    553  1.1  tron "#XML_SetXmlDeclHandler" >XML_SetXmlDeclHandler</a></code> function to
    554  1.1  tron set a handler that uses the information in the XML declaration to
    555  1.1  tron determine what to do.  This example shows how to check that only a
    556  1.1  tron version number of <code>"1.0"</code> is accepted:</p>
    557  1.1  tron 
    558  1.1  tron <pre class="eg">
    559  1.1  tron static int wrong_version;
    560  1.1  tron static XML_Parser parser;
    561  1.1  tron 
    562  1.1  tron static void XMLCALL
    563  1.1  tron xmldecl_handler(void            *userData,
    564  1.1  tron                 const XML_Char  *version,
    565  1.1  tron                 const XML_Char  *encoding,
    566  1.1  tron                 int              standalone)
    567  1.1  tron {
    568  1.1  tron   static const XML_Char Version_1_0[] = {'1', '.', '0', 0};
    569  1.1  tron 
    570  1.1  tron   int i;
    571  1.1  tron 
    572  1.1  tron   for (i = 0; i &lt; (sizeof(Version_1_0) / sizeof(Version_1_0[0])); ++i) {
    573  1.1  tron     if (version[i] != Version_1_0[i]) {
    574  1.1  tron       wrong_version = 1;
    575  1.1  tron       /* also clear all other handlers: */
    576  1.1  tron       XML_SetCharacterDataHandler(parser, NULL);
    577  1.1  tron       ...
    578  1.1  tron       return;
    579  1.1  tron     }
    580  1.1  tron   }
    581  1.1  tron   ...
    582  1.1  tron }
    583  1.1  tron </pre>
    584  1.1  tron 
    585  1.1  tron <h3>Namespace Processing</h3>
    586  1.1  tron 
    587  1.1  tron <p>When the parser is created using the <code><a href=
    588  1.1  tron "#XML_ParserCreateNS" >XML_ParserCreateNS</a></code>, function, Expat
    589  1.1  tron performs namespace processing. Under namespace processing, Expat
    590  1.1  tron consumes <code>xmlns</code> and <code>xmlns:...</code> attributes,
    591  1.1  tron which declare namespaces for the scope of the element in which they
    592  1.1  tron occur. This means that your start handler will not see these
    593  1.1  tron attributes.  Your application can still be informed of these
    594  1.1  tron declarations by setting namespace declaration handlers with <a href=
    595  1.1  tron "#XML_SetNamespaceDeclHandler"
    596  1.1  tron ><code>XML_SetNamespaceDeclHandler</code></a>.</p>
    597  1.1  tron 
    598  1.1  tron <p>Element type and attribute names that belong to a given namespace
    599  1.1  tron are passed to the appropriate handler in expanded form. By default
    600  1.1  tron this expanded form is a concatenation of the namespace URI, the
    601  1.1  tron separator character (which is the 2nd argument to <code><a href=
    602  1.1  tron "#XML_ParserCreateNS" >XML_ParserCreateNS</a></code>), and the local
    603  1.1  tron name (i.e. the part after the colon). Names with undeclared prefixes
    604  1.1  tron are not well-formed when namespace processing is enabled, and will
    605  1.1  tron trigger an error. Unprefixed attribute names are never expanded,
    606  1.1  tron and unprefixed element names are only expanded when they are in the
    607  1.1  tron scope of a default namespace.</p>
    608  1.1  tron 
    609  1.1  tron <p>However if <code><a href= "#XML_SetReturnNSTriplet"
    610  1.1  tron >XML_SetReturnNSTriplet</a></code> has been called with a non-zero
    611  1.1  tron <code>do_nst</code> parameter, then the expanded form for names with
    612  1.1  tron an explicit prefix is a concatenation of: URI, separator, local name,
    613  1.1  tron separator, prefix.</p>
    614  1.1  tron 
    615  1.1  tron <p>You can set handlers for the start of a namespace declaration and
    616  1.1  tron for the end of a scope of a declaration with the <code><a href=
    617  1.1  tron "#XML_SetNamespaceDeclHandler" >XML_SetNamespaceDeclHandler</a></code>
    618  1.1  tron function.  The StartNamespaceDeclHandler is called prior to the start
    619  1.1  tron tag handler and the EndNamespaceDeclHandler is called after the
    620  1.1  tron corresponding end tag that ends the namespace's scope.  The namespace
    621  1.1  tron start handler gets passed the prefix and URI for the namespace.  For a
    622  1.1  tron default namespace declaration (xmlns='...'), the prefix will be null.
    623  1.1  tron The URI will be null for the case where the default namespace is being
    624  1.1  tron unset.  The namespace end handler just gets the prefix for the closing
    625  1.1  tron scope.</p>
    626  1.1  tron 
    627  1.1  tron <p>These handlers are called for each declaration. So if, for
    628  1.1  tron instance, a start tag had three namespace declarations, then the
    629  1.1  tron StartNamespaceDeclHandler would be called three times before the start
    630  1.1  tron tag handler is called, once for each declaration.</p>
    631  1.1  tron 
    632  1.1  tron <h3>Character Encodings</h3>
    633  1.1  tron 
    634  1.1  tron <p>While XML is based on Unicode, and every XML processor is required
    635  1.1  tron to recognized UTF-8 and UTF-16 (1 and 2 byte encodings of Unicode),
    636  1.1  tron other encodings may be declared in XML documents or entities. For the
    637  1.1  tron main document, an XML declaration may contain an encoding
    638  1.1  tron declaration:</p>
    639  1.1  tron <pre>
    640  1.1  tron &lt;?xml version="1.0" encoding="ISO-8859-2"?&gt;
    641  1.1  tron </pre>
    642  1.1  tron 
    643  1.1  tron <p>External parsed entities may begin with a text declaration, which
    644  1.1  tron looks like an XML declaration with just an encoding declaration:</p>
    645  1.1  tron <pre>
    646  1.1  tron &lt;?xml encoding="Big5"?&gt;
    647  1.1  tron </pre>
    648  1.1  tron 
    649  1.1  tron <p>With Expat, you may also specify an encoding at the time of
    650  1.1  tron creating a parser. This is useful when the encoding information may
    651  1.1  tron come from a source outside the document itself (like a higher level
    652  1.1  tron protocol.)</p>
    653  1.1  tron 
    654  1.1  tron <p><a name="builtin_encodings"></a>There are four built-in encodings
    655  1.1  tron in Expat:</p>
    656  1.1  tron <ul>
    657  1.1  tron <li>UTF-8</li>
    658  1.1  tron <li>UTF-16</li>
    659  1.1  tron <li>ISO-8859-1</li>
    660  1.1  tron <li>US-ASCII</li>
    661  1.1  tron </ul>
    662  1.1  tron 
    663  1.1  tron <p>Anything else discovered in an encoding declaration or in the
    664  1.1  tron protocol encoding specified in the parser constructor, triggers a call
    665  1.1  tron to the <code>UnknownEncodingHandler</code>. This handler gets passed
    666  1.1  tron the encoding name and a pointer to an <code>XML_Encoding</code> data
    667  1.1  tron structure. Your handler must fill in this structure and return
    668  1.1  tron <code>XML_STATUS_OK</code> if it knows how to deal with the
    669  1.1  tron encoding. Otherwise the handler should return
    670  1.1  tron <code>XML_STATUS_ERROR</code>.  The handler also gets passed a pointer
    671  1.1  tron to an optional application data structure that you may indicate when
    672  1.1  tron you set the handler.</p>
    673  1.1  tron 
    674  1.1  tron <p>Expat places restrictions on character encodings that it can
    675  1.1  tron support by filling in the <code>XML_Encoding</code> structure.
    676  1.1  tron include file:</p>
    677  1.1  tron <ol>
    678  1.1  tron <li>Every ASCII character that can appear in a well-formed XML document
    679  1.1  tron must be represented by a single byte, and that byte must correspond to
    680  1.1  tron it's ASCII encoding (except for the characters $@\^'{}~)</li>
    681  1.1  tron <li>Characters must be encoded in 4 bytes or less.</li>
    682  1.1  tron <li>All characters encoded must have Unicode scalar values less than or
    683  1.1  tron equal to 65535 (0xFFFF)<em>This does not apply to the built-in support
    684  1.1  tron for UTF-16 and UTF-8</em></li>
    685  1.1  tron <li>No character may be encoded by more that one distinct sequence of
    686  1.1  tron bytes</li>
    687  1.1  tron </ol>
    688  1.1  tron 
    689  1.1  tron <p><code>XML_Encoding</code> contains an array of integers that
    690  1.1  tron correspond to the 1st byte of an encoding sequence. If the value in
    691  1.1  tron the array for a byte is zero or positive, then the byte is a single
    692  1.1  tron byte encoding that encodes the Unicode scalar value contained in the
    693  1.1  tron array. A -1 in this array indicates a malformed byte. If the value is
    694  1.1  tron -2, -3, or -4, then the byte is the beginning of a 2, 3, or 4 byte
    695  1.1  tron sequence respectively. Multi-byte sequences are sent to the convert
    696  1.1  tron function pointed at in the <code>XML_Encoding</code> structure. This
    697  1.1  tron function should return the Unicode scalar value for the sequence or -1
    698  1.1  tron if the sequence is malformed.</p>
    699  1.1  tron 
    700  1.1  tron <p>One pitfall that novice Expat users are likely to fall into is that
    701  1.1  tron although Expat may accept input in various encodings, the strings that
    702  1.1  tron it passes to the handlers are always encoded in UTF-8 or UTF-16
    703  1.1  tron (depending on how Expat was compiled). Your application is responsible
    704  1.1  tron for any translation of these strings into other encodings.</p>
    705  1.1  tron 
    706  1.1  tron <h3>Handling External Entity References</h3>
    707  1.1  tron 
    708  1.1  tron <p>Expat does not read or parse external entities directly. Note that
    709  1.1  tron any external DTD is a special case of an external entity.  If you've
    710  1.1  tron set no <code>ExternalEntityRefHandler</code>, then external entity
    711  1.1  tron references are silently ignored. Otherwise, it calls your handler with
    712  1.1  tron the information needed to read and parse the external entity.</p>
    713  1.1  tron 
    714  1.1  tron <p>Your handler isn't actually responsible for parsing the entity, but
    715  1.1  tron it is responsible for creating a subsidiary parser with <code><a href=
    716  1.1  tron "#XML_ExternalEntityParserCreate"
    717  1.1  tron >XML_ExternalEntityParserCreate</a></code> that will do the job. This
    718  1.1  tron returns an instance of <code>XML_Parser</code> that has handlers and
    719  1.1  tron other data structures initialized from the parent parser. You may then
    720  1.1  tron use <code><a href= "#XML_Parse" >XML_Parse</a></code> or <code><a
    721  1.1  tron href= "#XML_ParseBuffer">XML_ParseBuffer</a></code> calls against this
    722  1.1  tron parser.  Since external entities my refer to other external entities,
    723  1.1  tron your handler should be prepared to be called recursively.</p>
    724  1.1  tron 
    725  1.1  tron <h3>Parsing DTDs</h3>
    726  1.1  tron 
    727  1.1  tron <p>In order to parse parameter entities, before starting the parse,
    728  1.1  tron you must call <code><a href= "#XML_SetParamEntityParsing"
    729  1.1  tron >XML_SetParamEntityParsing</a></code> with one of the following
    730  1.1  tron arguments:</p>
    731  1.1  tron <dl>
    732  1.1  tron <dt><code>XML_PARAM_ENTITY_PARSING_NEVER</code></dt>
    733  1.1  tron <dd>Don't parse parameter entities or the external subset</dd>
    734  1.1  tron <dt><code>XML_PARAM_ENTITY_PARSING_UNLESS_STANDALONE</code></dt>
    735  1.1  tron <dd>Parse parameter entites and the external subset unless
    736  1.1  tron <code>standalone</code> was set to "yes" in the XML declaration.</dd>
    737  1.1  tron <dt><code>XML_PARAM_ENTITY_PARSING_ALWAYS</code></dt>
    738  1.1  tron <dd>Always parse parameter entities and the external subset</dd>
    739  1.1  tron </dl>
    740  1.1  tron 
    741  1.1  tron <p>In order to read an external DTD, you also have to set an external
    742  1.1  tron entity reference handler as described above.</p>
    743  1.1  tron 
    744  1.1  tron <h3 id="stop-resume">Temporarily Stopping Parsing</h3>
    745  1.1  tron 
    746  1.1  tron <p>Expat 1.95.8 introduces a new feature: its now possible to stop
    747  1.1  tron parsing temporarily from within a handler function, even if more data
    748  1.1  tron has already been passed into the parser.  Applications for this
    749  1.1  tron include</p>
    750  1.1  tron 
    751  1.1  tron <ul>
    752  1.1  tron   <li>Supporting the <a href= "http://www.w3.org/TR/xinclude/"
    753  1.1  tron   >XInclude</a> specification.</li>
    754  1.1  tron 
    755  1.1  tron   <li>Delaying further processing until additional information is
    756  1.1  tron   available from some other source.</li>
    757  1.1  tron 
    758  1.1  tron   <li>Adjusting processor load as task priorities shift within an
    759  1.1  tron   application.</li>
    760  1.1  tron 
    761  1.1  tron   <li>Stopping parsing completely (simply free or reset the parser
    762  1.1  tron   instead of resuming in the outer parsing loop).  This can be useful
    763  1.1  tron   if a application-domain error is found in the XML being parsed or if
    764  1.1  tron   the result of the parse is determined not to be useful after
    765  1.1  tron   all.</li>
    766  1.1  tron </ul>
    767  1.1  tron 
    768  1.1  tron <p>To take advantage of this feature, the main parsing loop of an
    769  1.1  tron application needs to support this specifically.  It cannot be
    770  1.1  tron supported with a parsing loop compatible with Expat 1.95.7 or
    771  1.1  tron earlier (though existing loops will continue to work without
    772  1.1  tron supporting the stop/resume feature).</p>
    773  1.1  tron 
    774  1.1  tron <p>An application that uses this feature for a single parser will have
    775  1.1  tron the rough structure (in pseudo-code):</p>
    776  1.1  tron 
    777  1.1  tron <pre class="pseudocode">
    778  1.1  tron fd = open_input()
    779  1.1  tron p = create_parser()
    780  1.1  tron 
    781  1.1  tron if parse_xml(p, fd) {
    782  1.1  tron   /* suspended */
    783  1.1  tron 
    784  1.1  tron   int suspended = 1;
    785  1.1  tron 
    786  1.1  tron   while (suspended) {
    787  1.1  tron     do_something_else()
    788  1.1  tron     if ready_to_resume() {
    789  1.1  tron       suspended = continue_parsing(p, fd);
    790  1.1  tron     }
    791  1.1  tron   }
    792  1.1  tron }
    793  1.1  tron </pre>
    794  1.1  tron 
    795  1.1  tron <p>An application that may resume any of several parsers based on
    796  1.1  tron input (either from the XML being parsed or some other source) will
    797  1.1  tron certainly have more interesting control structures.</p>
    798  1.1  tron 
    799  1.1  tron <p>This C function could be used for the <code>parse_xml</code>
    800  1.1  tron function mentioned in the pseudo-code above:</p>
    801  1.1  tron 
    802  1.1  tron <pre class="eg">
    803  1.1  tron #define BUFF_SIZE 10240
    804  1.1  tron 
    805  1.1  tron /* Parse a document from the open file descriptor 'fd' until the parse
    806  1.1  tron    is complete (the document has been completely parsed, or there's
    807  1.1  tron    been an error), or the parse is stopped.  Return non-zero when
    808  1.1  tron    the parse is merely suspended.
    809  1.1  tron */
    810  1.1  tron int
    811  1.1  tron parse_xml(XML_Parser p, int fd)
    812  1.1  tron {
    813  1.1  tron   for (;;) {
    814  1.1  tron     int last_chunk;
    815  1.1  tron     int bytes_read;
    816  1.1  tron     enum XML_Status status;
    817  1.1  tron 
    818  1.1  tron     void *buff = XML_GetBuffer(p, BUFF_SIZE);
    819  1.1  tron     if (buff == NULL) {
    820  1.1  tron       /* handle error... */
    821  1.1  tron       return 0;
    822  1.1  tron     }
    823  1.1  tron     bytes_read = read(fd, buff, BUFF_SIZE);
    824  1.1  tron     if (bytes_read &lt; 0) {
    825  1.1  tron       /* handle error... */
    826  1.1  tron       return 0;
    827  1.1  tron     }
    828  1.1  tron     status = XML_ParseBuffer(p, bytes_read, bytes_read == 0);
    829  1.1  tron     switch (status) {
    830  1.1  tron       case XML_STATUS_ERROR:
    831  1.1  tron         /* handle error... */
    832  1.1  tron         return 0;
    833  1.1  tron       case XML_STATUS_SUSPENDED:
    834  1.1  tron         return 1;
    835  1.1  tron     }
    836  1.1  tron     if (bytes_read == 0)
    837  1.1  tron       return 0;
    838  1.1  tron   }
    839  1.1  tron }
    840  1.1  tron </pre>
    841  1.1  tron 
    842  1.1  tron <p>The corresponding <code>continue_parsing</code> function is
    843  1.1  tron somewhat simpler, since it only need deal with the return code from
    844  1.1  tron <code><a href= "#XML_ResumeParser">XML_ResumeParser</a></code>; it can
    845  1.1  tron delegate the input handling to the <code>parse_xml</code>
    846  1.1  tron function:</p>
    847  1.1  tron 
    848  1.1  tron <pre class="eg">
    849  1.1  tron /* Continue parsing a document which had been suspended.  The 'p' and
    850  1.1  tron    'fd' arguments are the same as passed to parse_xml().  Return
    851  1.1  tron    non-zero when the parse is suspended.
    852  1.1  tron */
    853  1.1  tron int
    854  1.1  tron continue_parsing(XML_Parser p, int fd)
    855  1.1  tron {
    856  1.1  tron   enum XML_Status status = XML_ResumeParser(p);
    857  1.1  tron   switch (status) {
    858  1.1  tron     case XML_STATUS_ERROR:
    859  1.1  tron       /* handle error... */
    860  1.1  tron       return 0;
    861  1.1  tron     case XML_ERROR_NOT_SUSPENDED:
    862  1.1  tron       /* handle error... */
    863  1.1  tron       return 0;.
    864  1.1  tron     case XML_STATUS_SUSPENDED:
    865  1.1  tron       return 1;
    866  1.1  tron   }
    867  1.1  tron   return parse_xml(p, fd);
    868  1.1  tron }
    869  1.1  tron </pre>
    870  1.1  tron 
    871  1.1  tron <p>Now that we've seen what a mess the top-level parsing loop can
    872  1.1  tron become, what have we gained?  Very simply, we can now use the <code><a
    873  1.1  tron href= "#XML_StopParser" >XML_StopParser</a></code> function to stop
    874  1.1  tron parsing, without having to go to great lengths to avoid additional
    875  1.1  tron processing that we're expecting to ignore.  As a bonus, we get to stop
    876  1.1  tron parsing <em>temporarily</em>, and come back to it when we're
    877  1.1  tron ready.</p>
    878  1.1  tron 
    879  1.1  tron <p>To stop parsing from a handler function, use the <code><a href=
    880  1.1  tron "#XML_StopParser" >XML_StopParser</a></code> function.  This function
    881  1.1  tron takes two arguments; the parser being stopped and a flag indicating
    882  1.1  tron whether the parse can be resumed in the future.</p>
    883  1.1  tron 
    884  1.1  tron <!-- XXX really need more here -->
    885  1.1  tron 
    886  1.1  tron 
    887  1.1  tron <hr />
    888  1.1  tron <!-- ================================================================ -->
    889  1.1  tron 
    890  1.1  tron <h2><a name="reference">Expat Reference</a></h2>
    891  1.1  tron 
    892  1.1  tron <h3><a name="creation">Parser Creation</a></h3>
    893  1.1  tron 
    894  1.1  tron <pre class="fcndec" id="XML_ParserCreate">
    895  1.1  tron XML_Parser XMLCALL
    896  1.1  tron XML_ParserCreate(const XML_Char *encoding);
    897  1.1  tron </pre>
    898  1.1  tron <div class="fcndef">
    899  1.1  tron Construct a new parser. If encoding is non-null, it specifies a
    900  1.1  tron character encoding to use for the document. This overrides the document
    901  1.1  tron encoding declaration. There are four built-in encodings:
    902  1.1  tron <ul>
    903  1.1  tron <li>US-ASCII</li>
    904  1.1  tron <li>UTF-8</li>
    905  1.1  tron <li>UTF-16</li>
    906  1.1  tron <li>ISO-8859-1</li>
    907  1.1  tron </ul>
    908  1.1  tron Any other value will invoke a call to the UnknownEncodingHandler.
    909  1.1  tron </div>
    910  1.1  tron 
    911  1.1  tron <pre class="fcndec" id="XML_ParserCreateNS">
    912  1.1  tron XML_Parser XMLCALL
    913  1.1  tron XML_ParserCreateNS(const XML_Char *encoding,
    914  1.1  tron                    XML_Char sep);
    915  1.1  tron </pre>
    916  1.1  tron <div class="fcndef">
    917  1.1  tron Constructs a new parser that has namespace processing in effect. Namespace
    918  1.1  tron expanded element names and attribute names are returned as a concatenation
    919  1.1  tron of the namespace URI, <em>sep</em>, and the local part of the name. This
    920  1.1  tron means that you should pick a character for <em>sep</em> that can't be
    921  1.1  tron part of a legal URI. There is a special case when <em>sep</em> is the null
    922  1.1  tron character <code>'\0'</code>: the namespace URI and the local part will be
    923  1.1  tron concatenated without any separator - this is intended to support RDF processors.
    924  1.1  tron It is a programming error to use the null separator with 
    925  1.1  tron <a href= "#XML_SetReturnNSTriplet">namespace triplets</a>.</div>
    926  1.1  tron 
    927  1.1  tron <pre class="fcndec" id="XML_ParserCreate_MM">
    928  1.1  tron XML_Parser XMLCALL
    929  1.1  tron XML_ParserCreate_MM(const XML_Char *encoding,
    930  1.1  tron                     const XML_Memory_Handling_Suite *ms,
    931  1.1  tron 		    const XML_Char *sep);
    932  1.1  tron </pre>
    933  1.1  tron <pre class="signature">
    934  1.1  tron typedef struct {
    935  1.1  tron   void *(XMLCALL *malloc_fcn)(size_t size);
    936  1.1  tron   void *(XMLCALL *realloc_fcn)(void *ptr, size_t size);
    937  1.1  tron   void (XMLCALL *free_fcn)(void *ptr);
    938  1.1  tron } XML_Memory_Handling_Suite;
    939  1.1  tron </pre>
    940  1.1  tron <div class="fcndef">
    941  1.1  tron <p>Construct a new parser using the suite of memory handling functions
    942  1.1  tron specified in <code>ms</code>. If <code>ms</code> is NULL, then use the
    943  1.1  tron standard set of memory management functions. If <code>sep</code> is
    944  1.1  tron non NULL, then namespace processing is enabled in the created parser
    945  1.1  tron and the character pointed at by sep is used as the separator between
    946  1.1  tron the namespace URI and the local part of the name.</p>
    947  1.1  tron </div>
    948  1.1  tron 
    949  1.1  tron <pre class="fcndec" id="XML_ExternalEntityParserCreate">
    950  1.1  tron XML_Parser XMLCALL
    951  1.1  tron XML_ExternalEntityParserCreate(XML_Parser p,
    952  1.1  tron                                const XML_Char *context,
    953  1.1  tron                                const XML_Char *encoding);
    954  1.1  tron </pre>
    955  1.1  tron <div class="fcndef">
    956  1.1  tron Construct a new <code>XML_Parser</code> object for parsing an external
    957  1.1  tron general entity. Context is the context argument passed in a call to a
    958  1.1  tron ExternalEntityRefHandler. Other state information such as handlers,
    959  1.1  tron user data, namespace processing is inherited from the parser passed as
    960  1.1  tron the 1st argument. So you shouldn't need to call any of the behavior
    961  1.1  tron changing functions on this parser (unless you want it to act
    962  1.1  tron differently than the parent parser).
    963  1.1  tron </div>
    964  1.1  tron 
    965  1.1  tron <pre class="fcndec" id="XML_ParserFree">
    966  1.1  tron void XMLCALL
    967  1.1  tron XML_ParserFree(XML_Parser p);
    968  1.1  tron </pre>
    969  1.1  tron <div class="fcndef">
    970  1.1  tron Free memory used by the parser. Your application is responsible for
    971  1.1  tron freeing any memory associated with <a href="#userdata">user data</a>.
    972  1.1  tron </div>
    973  1.1  tron 
    974  1.1  tron <pre class="fcndec" id="XML_ParserReset">
    975  1.1  tron XML_Bool XMLCALL
    976  1.1  tron XML_ParserReset(XML_Parser p,
    977  1.1  tron                 const XML_Char *encoding);
    978  1.1  tron </pre>
    979  1.1  tron <div class="fcndef">
    980  1.1  tron Clean up the memory structures maintained by the parser so that it may
    981  1.1  tron be used again.  After this has been called, <code>parser</code> is
    982  1.1  tron ready to start parsing a new document.  All handlers are cleared from
    983  1.1  tron the parser, except for the unknownEncodingHandler.  The parser's external
    984  1.1  tron state is re-initialized except for the values of ns and ns_triplets.
    985  1.1  tron This function may not be used on a parser created using <code><a href=
    986  1.1  tron "#XML_ExternalEntityParserCreate" >XML_ExternalEntityParserCreate</a
    987  1.1  tron ></code>; it will return <code>XML_FALSE</code> in that case.  Returns
    988  1.1  tron <code>XML_TRUE</code> on success.  Your application is responsible for
    989  1.1  tron dealing with any memory associated with <a href="#userdata">user data</a>.
    990  1.1  tron </div>
    991  1.1  tron 
    992  1.1  tron <h3><a name="parsing">Parsing</a></h3>
    993  1.1  tron 
    994  1.1  tron <p>To state the obvious: the three parsing functions <code><a href=
    995  1.1  tron "#XML_Parse" >XML_Parse</a></code>, <code><a href= "#XML_ParseBuffer">
    996  1.1  tron XML_ParseBuffer</a></code> and <code><a href= "#XML_GetBuffer">
    997  1.1  tron XML_GetBuffer</a></code> must not be called from within a handler
    998  1.1  tron unless they operate on a separate parser instance, that is, one that
    999  1.1  tron did not call the handler. For example, it is OK to call the parsing
   1000  1.1  tron functions from within an <code>XML_ExternalEntityRefHandler</code>,
   1001  1.1  tron if they apply to the parser created by
   1002  1.1  tron <code><a href= "#XML_ExternalEntityParserCreate"
   1003  1.1  tron >XML_ExternalEntityParserCreate</a></code>.</p>
   1004  1.1  tron 
   1005  1.1  tron <p>Note: the <code>len</code> argument passed to these functions
   1006  1.1  tron should be considerably less than the maximum value for an integer,
   1007  1.1  tron as it could create an integer overflow situation if the added
   1008  1.1  tron lengths of a buffer and the unprocessed portion of the previous buffer
   1009  1.1  tron exceed the maximum integer value. Input data at the end of a buffer
   1010  1.1  tron will remain unprocessed if it is part of an XML token for which the
   1011  1.1  tron end is not part of that buffer.</p>
   1012  1.1  tron 
   1013  1.1  tron <pre class="fcndec" id="XML_Parse">
   1014  1.1  tron enum XML_Status XMLCALL
   1015  1.1  tron XML_Parse(XML_Parser p,
   1016  1.1  tron           const char *s,
   1017  1.1  tron           int len,
   1018  1.1  tron           int isFinal);
   1019  1.1  tron </pre>
   1020  1.1  tron <pre class="signature">
   1021  1.1  tron enum XML_Status {
   1022  1.1  tron   XML_STATUS_ERROR = 0,
   1023  1.1  tron   XML_STATUS_OK = 1
   1024  1.1  tron };
   1025  1.1  tron </pre>
   1026  1.1  tron <div class="fcndef">
   1027  1.1  tron Parse some more of the document. The string <code>s</code> is a buffer
   1028  1.1  tron containing part (or perhaps all) of the document. The number of bytes of s
   1029  1.1  tron that are part of the document is indicated by <code>len</code>. This means
   1030  1.1  tron that <code>s</code> doesn't have to be null terminated. It also means that
   1031  1.1  tron if <code>len</code> is larger than the number of bytes in the block of
   1032  1.1  tron memory that <code>s</code> points at, then a memory fault is likely. The
   1033  1.1  tron <code>isFinal</code> parameter informs the parser that this is the last
   1034  1.1  tron piece of the document. Frequently, the last piece is empty (i.e.
   1035  1.1  tron <code>len</code> is zero.)
   1036  1.1  tron If a parse error occurred, it returns <code>XML_STATUS_ERROR</code>.
   1037  1.1  tron Otherwise it returns <code>XML_STATUS_OK</code> value.
   1038  1.1  tron </div>
   1039  1.1  tron 
   1040  1.1  tron <pre class="fcndec" id="XML_ParseBuffer">
   1041  1.1  tron enum XML_Status XMLCALL
   1042  1.1  tron XML_ParseBuffer(XML_Parser p,
   1043  1.1  tron                 int len,
   1044  1.1  tron                 int isFinal);
   1045  1.1  tron </pre>
   1046  1.1  tron <div class="fcndef">
   1047  1.1  tron This is just like <code><a href= "#XML_Parse" >XML_Parse</a></code>,
   1048  1.1  tron except in this case Expat provides the buffer.  By obtaining the
   1049  1.1  tron buffer from Expat with the <code><a href= "#XML_GetBuffer"
   1050  1.1  tron >XML_GetBuffer</a></code> function, the application can avoid double
   1051  1.1  tron copying of the input.
   1052  1.1  tron </div>
   1053  1.1  tron 
   1054  1.1  tron <pre class="fcndec" id="XML_GetBuffer">
   1055  1.1  tron void * XMLCALL
   1056  1.1  tron XML_GetBuffer(XML_Parser p,
   1057  1.1  tron               int len);
   1058  1.1  tron </pre>
   1059  1.1  tron <div class="fcndef">
   1060  1.1  tron Obtain a buffer of size <code>len</code> to read a piece of the document
   1061  1.1  tron into. A NULL value is returned if Expat can't allocate enough memory for
   1062  1.1  tron this buffer. This has to be called prior to every call to
   1063  1.1  tron <code><a href= "#XML_ParseBuffer" >XML_ParseBuffer</a></code>. A
   1064  1.1  tron typical use would look like this:
   1065  1.1  tron 
   1066  1.1  tron <pre class="eg">
   1067  1.1  tron for (;;) {
   1068  1.1  tron   int bytes_read;
   1069  1.1  tron   void *buff = XML_GetBuffer(p, BUFF_SIZE);
   1070  1.1  tron   if (buff == NULL) {
   1071  1.1  tron     /* handle error */
   1072  1.1  tron   }
   1073  1.1  tron 
   1074  1.1  tron   bytes_read = read(docfd, buff, BUFF_SIZE);
   1075  1.1  tron   if (bytes_read &lt; 0) {
   1076  1.1  tron     /* handle error */
   1077  1.1  tron   }
   1078  1.1  tron 
   1079  1.1  tron   if (! XML_ParseBuffer(p, bytes_read, bytes_read == 0)) {
   1080  1.1  tron     /* handle parse error */
   1081  1.1  tron   }
   1082  1.1  tron 
   1083  1.1  tron   if (bytes_read == 0)
   1084  1.1  tron     break;
   1085  1.1  tron }
   1086  1.1  tron </pre>
   1087  1.1  tron </div>
   1088  1.1  tron 
   1089  1.1  tron <pre class="fcndec" id="XML_StopParser">
   1090  1.1  tron enum XML_Status XMLCALL
   1091  1.1  tron XML_StopParser(XML_Parser p,
   1092  1.1  tron                XML_Bool resumable);
   1093  1.1  tron </pre>
   1094  1.1  tron <div class="fcndef">
   1095  1.1  tron 
   1096  1.1  tron <p>Stops parsing, causing <code><a href= "#XML_Parse"
   1097  1.1  tron >XML_Parse</a></code> or <code><a href= "#XML_ParseBuffer"
   1098  1.1  tron >XML_ParseBuffer</a></code> to return.  Must be called from within a
   1099  1.1  tron call-back handler, except when aborting (when <code>resumable</code>
   1100  1.1  tron is <code>XML_FALSE</code>) an already suspended parser.  Some
   1101  1.1  tron call-backs may still follow because they would otherwise get
   1102  1.1  tron lost, including
   1103  1.1  tron <ul>
   1104  1.1  tron   <li> the end element handler for empty elements when stopped in the
   1105  1.1  tron        start element handler,</li>
   1106  1.1  tron   <li> the end namespace declaration handler when stopped in the end
   1107  1.1  tron        element handler,</li>
   1108  1.1  tron   <li> the character data handler when stopped in the character data handler
   1109  1.1  tron        while making multiple call-backs on a contiguous chunk of characters,</li>
   1110  1.1  tron </ul>
   1111  1.1  tron and possibly others.</p>
   1112  1.1  tron 
   1113  1.1  tron <p>This can be called from most handlers, including DTD related
   1114  1.1  tron call-backs, except when parsing an external parameter entity and
   1115  1.1  tron <code>resumable</code> is <code>XML_TRUE</code>.  Returns
   1116  1.1  tron <code>XML_STATUS_OK</code> when successful,
   1117  1.1  tron <code>XML_STATUS_ERROR</code> otherwise.  The possible error codes
   1118  1.1  tron are:</p>
   1119  1.1  tron <dl>
   1120  1.1  tron   <dt><code>XML_ERROR_SUSPENDED</code></dt>
   1121  1.1  tron   <dd>when suspending an already suspended parser.</dd>
   1122  1.1  tron   <dt><code>XML_ERROR_FINISHED</code></dt>
   1123  1.1  tron   <dd>when the parser has already finished.</dd>
   1124  1.1  tron   <dt><code>XML_ERROR_SUSPEND_PE</code></dt>
   1125  1.1  tron   <dd>when suspending while parsing an external PE.</dd>
   1126  1.1  tron </dl>
   1127  1.1  tron 
   1128  1.1  tron <p>Since the stop/resume feature requires application support in the
   1129  1.1  tron outer parsing loop, it is an error to call this function for a parser
   1130  1.1  tron not being handled appropriately; see <a href= "#stop-resume"
   1131  1.1  tron >Temporarily Stopping Parsing</a> for more information.</p>
   1132  1.1  tron 
   1133  1.1  tron <p>When <code>resumable</code> is <code>XML_TRUE</code> then parsing
   1134  1.1  tron is <em>suspended</em>, that is, <code><a href= "#XML_Parse"
   1135  1.1  tron >XML_Parse</a></code> and <code><a href= "#XML_ParseBuffer"
   1136  1.1  tron >XML_ParseBuffer</a></code> return <code>XML_STATUS_SUSPENDED</code>.
   1137  1.1  tron Otherwise, parsing is <em>aborted</em>, that is, <code><a href=
   1138  1.1  tron "#XML_Parse" >XML_Parse</a></code> and <code><a href=
   1139  1.1  tron "#XML_ParseBuffer" >XML_ParseBuffer</a></code> return
   1140  1.1  tron <code>XML_STATUS_ERROR</code> with error code
   1141  1.1  tron <code>XML_ERROR_ABORTED</code>.</p>
   1142  1.1  tron 
   1143  1.1  tron <p><strong>Note:</strong>
   1144  1.1  tron This will be applied to the current parser instance only, that is, if
   1145  1.1  tron there is a parent parser then it will continue parsing when the
   1146  1.1  tron external entity reference handler returns.  It is up to the
   1147  1.1  tron implementation of that handler to call <code><a href=
   1148  1.1  tron "#XML_StopParser" >XML_StopParser</a></code> on the parent parser
   1149  1.1  tron (recursively), if one wants to stop parsing altogether.</p>
   1150  1.1  tron 
   1151  1.1  tron <p>When suspended, parsing can be resumed by calling <code><a href=
   1152  1.1  tron "#XML_ResumeParser" >XML_ResumeParser</a></code>.</p>
   1153  1.1  tron 
   1154  1.1  tron <p>New in Expat 1.95.8.</p>
   1155  1.1  tron </div>
   1156  1.1  tron 
   1157  1.1  tron <pre class="fcndec" id="XML_ResumeParser">
   1158  1.1  tron enum XML_Status XMLCALL
   1159  1.1  tron XML_ResumeParser(XML_Parser p);
   1160  1.1  tron </pre>
   1161  1.1  tron <div class="fcndef">
   1162  1.1  tron <p>Resumes parsing after it has been suspended with <code><a href=
   1163  1.1  tron "#XML_StopParser" >XML_StopParser</a></code>.  Must not be called from
   1164  1.1  tron within a handler call-back.  Returns same status codes as <code><a
   1165  1.1  tron href= "#XML_Parse">XML_Parse</a></code> or <code><a href=
   1166  1.1  tron "#XML_ParseBuffer" >XML_ParseBuffer</a></code>.  An additional error
   1167  1.1  tron code, <code>XML_ERROR_NOT_SUSPENDED</code>, will be returned if the
   1168  1.1  tron parser was not currently suspended.</p>
   1169  1.1  tron 
   1170  1.1  tron <p><strong>Note:</strong>
   1171  1.1  tron This must be called on the most deeply nested child parser instance
   1172  1.1  tron first, and on its parent parser only after the child parser has
   1173  1.1  tron finished, to be applied recursively until the document entity's parser
   1174  1.1  tron is restarted.  That is, the parent parser will not resume by itself
   1175  1.1  tron and it is up to the application to call <code><a href=
   1176  1.1  tron "#XML_ResumeParser" >XML_ResumeParser</a></code> on it at the
   1177  1.1  tron appropriate moment.</p>
   1178  1.1  tron 
   1179  1.1  tron <p>New in Expat 1.95.8.</p>
   1180  1.1  tron </div>
   1181  1.1  tron 
   1182  1.1  tron <pre class="fcndec" id="XML_GetParsingStatus">
   1183  1.1  tron void XMLCALL
   1184  1.1  tron XML_GetParsingStatus(XML_Parser p,
   1185  1.1  tron                      XML_ParsingStatus *status);
   1186  1.1  tron </pre>
   1187  1.1  tron <pre class="signature">
   1188  1.1  tron enum XML_Parsing {
   1189  1.1  tron   XML_INITIALIZED,
   1190  1.1  tron   XML_PARSING,
   1191  1.1  tron   XML_FINISHED,
   1192  1.1  tron   XML_SUSPENDED
   1193  1.1  tron };
   1194  1.1  tron 
   1195  1.1  tron typedef struct {
   1196  1.1  tron   enum XML_Parsing parsing;
   1197  1.1  tron   XML_Bool finalBuffer;
   1198  1.1  tron } XML_ParsingStatus;
   1199  1.1  tron </pre>
   1200  1.1  tron <div class="fcndef">
   1201  1.1  tron <p>Returns status of parser with respect to being initialized,
   1202  1.1  tron parsing, finished, or suspended, and whether the final buffer is being
   1203  1.1  tron processed.  The <code>status</code> parameter <em>must not</em> be
   1204  1.1  tron NULL.</p>
   1205  1.1  tron 
   1206  1.1  tron <p>New in Expat 1.95.8.</p>
   1207  1.1  tron </div>
   1208  1.1  tron 
   1209  1.1  tron 
   1210  1.1  tron <h3><a name="setting">Handler Setting</a></h3>
   1211  1.1  tron 
   1212  1.1  tron <p>Although handlers are typically set prior to parsing and left alone, an
   1213  1.1  tron application may choose to set or change the handler for a parsing event
   1214  1.1  tron while the parse is in progress. For instance, your application may choose
   1215  1.1  tron to ignore all text not descended from a <code>para</code> element. One
   1216  1.1  tron way it could do this is to set the character handler when a para start tag
   1217  1.1  tron is seen, and unset it for the corresponding end tag.</p>
   1218  1.1  tron 
   1219  1.1  tron <p>A handler may be <em>unset</em> by providing a NULL pointer to the
   1220  1.1  tron appropriate handler setter. None of the handler setting functions have
   1221  1.1  tron a return value.</p>
   1222  1.1  tron 
   1223  1.1  tron <p>Your handlers will be receiving strings in arrays of type
   1224  1.1  tron <code>XML_Char</code>. This type is conditionally defined in expat.h as
   1225  1.1  tron either <code>char</code>, <code>wchar_t</code> or <code>unsigned short</code>.
   1226  1.1  tron The former implies UTF-8 encoding, the latter two imply UTF-16 encoding.
   1227  1.1  tron Note that you'll receive them in this form independent of the original
   1228  1.1  tron encoding of the document.</p>
   1229  1.1  tron 
   1230  1.1  tron <div class="handler">
   1231  1.1  tron <pre class="setter" id="XML_SetStartElementHandler">
   1232  1.1  tron void XMLCALL
   1233  1.1  tron XML_SetStartElementHandler(XML_Parser p,
   1234  1.1  tron                            XML_StartElementHandler start);
   1235  1.1  tron </pre>
   1236  1.1  tron <pre class="signature">
   1237  1.1  tron typedef void
   1238  1.1  tron (XMLCALL *XML_StartElementHandler)(void *userData,
   1239  1.1  tron                                    const XML_Char *name,
   1240  1.1  tron                                    const XML_Char **atts);
   1241  1.1  tron </pre>
   1242  1.1  tron <p>Set handler for start (and empty) tags. Attributes are passed to the start
   1243  1.1  tron handler as a pointer to a vector of char pointers. Each attribute seen in
   1244  1.1  tron a start (or empty) tag occupies 2 consecutive places in this vector: the
   1245  1.1  tron attribute name followed by the attribute value. These pairs are terminated
   1246  1.1  tron by a null pointer.</p>
   1247  1.1  tron <p>Note that an empty tag generates a call to both start and end handlers
   1248  1.1  tron (in that order).</p>
   1249  1.1  tron </div>
   1250  1.1  tron 
   1251  1.1  tron <div class="handler">
   1252  1.1  tron <pre class="setter" id="XML_SetEndElementHandler">
   1253  1.1  tron void XMLCALL
   1254  1.1  tron XML_SetEndElementHandler(XML_Parser p,
   1255  1.1  tron                          XML_EndElementHandler);
   1256  1.1  tron </pre>
   1257  1.1  tron <pre class="signature">
   1258  1.1  tron typedef void
   1259  1.1  tron (XMLCALL *XML_EndElementHandler)(void *userData,
   1260  1.1  tron                                  const XML_Char *name);
   1261  1.1  tron </pre>
   1262  1.1  tron <p>Set handler for end (and empty) tags. As noted above, an empty tag
   1263  1.1  tron generates a call to both start and end handlers.</p>
   1264  1.1  tron </div>
   1265  1.1  tron 
   1266  1.1  tron <div class="handler">
   1267  1.1  tron <pre class="setter" id="XML_SetElementHandler">
   1268  1.1  tron void XMLCALL
   1269  1.1  tron XML_SetElementHandler(XML_Parser p,
   1270  1.1  tron                       XML_StartElementHandler start,
   1271  1.1  tron                       XML_EndElementHandler end);
   1272  1.1  tron </pre>
   1273  1.1  tron <p>Set handlers for start and end tags with one call.</p>
   1274  1.1  tron </div>
   1275  1.1  tron 
   1276  1.1  tron <div class="handler">
   1277  1.1  tron <pre class="setter" id="XML_SetCharacterDataHandler">
   1278  1.1  tron void XMLCALL
   1279  1.1  tron XML_SetCharacterDataHandler(XML_Parser p,
   1280  1.1  tron                             XML_CharacterDataHandler charhndl)
   1281  1.1  tron </pre>
   1282  1.1  tron <pre class="signature">
   1283  1.1  tron typedef void
   1284  1.1  tron (XMLCALL *XML_CharacterDataHandler)(void *userData,
   1285  1.1  tron                                     const XML_Char *s,
   1286  1.1  tron                                     int len);
   1287  1.1  tron </pre>
   1288  1.1  tron <p>Set a text handler. The string your handler receives
   1289  1.1  tron is <em>NOT nul-terminated</em>. You have to use the length argument
   1290  1.1  tron to deal with the end of the string. A single block of contiguous text
   1291  1.1  tron free of markup may still result in a sequence of calls to this handler.
   1292  1.1  tron In other words, if you're searching for a pattern in the text, it may
   1293  1.1  tron be split across calls to this handler. Note: Setting this handler to NULL
   1294  1.1  tron may <em>NOT immediately</em> terminate call-backs if the parser is currently
   1295  1.1  tron processing such a single block of contiguous markup-free text, as the parser
   1296  1.1  tron will continue calling back until the end of the block is reached.</p>
   1297  1.1  tron </div>
   1298  1.1  tron 
   1299  1.1  tron <div class="handler">
   1300  1.1  tron <pre class="setter" id="XML_SetProcessingInstructionHandler">
   1301  1.1  tron void XMLCALL
   1302  1.1  tron XML_SetProcessingInstructionHandler(XML_Parser p,
   1303  1.1  tron                                     XML_ProcessingInstructionHandler proc)
   1304  1.1  tron </pre>
   1305  1.1  tron <pre class="signature">
   1306  1.1  tron typedef void
   1307  1.1  tron (XMLCALL *XML_ProcessingInstructionHandler)(void *userData,
   1308  1.1  tron                                             const XML_Char *target,
   1309  1.1  tron                                             const XML_Char *data);
   1310  1.1  tron 
   1311  1.1  tron </pre>
   1312  1.1  tron <p>Set a handler for processing instructions. The target is the first word
   1313  1.1  tron in the processing instruction. The data is the rest of the characters in
   1314  1.1  tron it after skipping all whitespace after the initial word.</p>
   1315  1.1  tron </div>
   1316  1.1  tron 
   1317  1.1  tron <div class="handler">
   1318  1.1  tron <pre class="setter" id="XML_SetCommentHandler">
   1319  1.1  tron void XMLCALL
   1320  1.1  tron XML_SetCommentHandler(XML_Parser p,
   1321  1.1  tron                       XML_CommentHandler cmnt)
   1322  1.1  tron </pre>
   1323  1.1  tron <pre class="signature">
   1324  1.1  tron typedef void
   1325  1.1  tron (XMLCALL *XML_CommentHandler)(void *userData,
   1326  1.1  tron                               const XML_Char *data);
   1327  1.1  tron </pre>
   1328  1.1  tron <p>Set a handler for comments. The data is all text inside the comment
   1329  1.1  tron delimiters.</p>
   1330  1.1  tron </div>
   1331  1.1  tron 
   1332  1.1  tron <div class="handler">
   1333  1.1  tron <pre class="setter" id="XML_SetStartCdataSectionHandler">
   1334  1.1  tron void XMLCALL
   1335  1.1  tron XML_SetStartCdataSectionHandler(XML_Parser p,
   1336  1.1  tron                                 XML_StartCdataSectionHandler start);
   1337  1.1  tron </pre>
   1338  1.1  tron <pre class="signature">
   1339  1.1  tron typedef void
   1340  1.1  tron (XMLCALL *XML_StartCdataSectionHandler)(void *userData);
   1341  1.1  tron </pre>
   1342  1.1  tron <p>Set a handler that gets called at the beginning of a CDATA section.</p>
   1343  1.1  tron </div>
   1344  1.1  tron 
   1345  1.1  tron <div class="handler">
   1346  1.1  tron <pre class="setter" id="XML_SetEndCdataSectionHandler">
   1347  1.1  tron void XMLCALL
   1348  1.1  tron XML_SetEndCdataSectionHandler(XML_Parser p,
   1349  1.1  tron                               XML_EndCdataSectionHandler end);
   1350  1.1  tron </pre>
   1351  1.1  tron <pre class="signature">
   1352  1.1  tron typedef void
   1353  1.1  tron (XMLCALL *XML_EndCdataSectionHandler)(void *userData);
   1354  1.1  tron </pre>
   1355  1.1  tron <p>Set a handler that gets called at the end of a CDATA section.</p>
   1356  1.1  tron </div>
   1357  1.1  tron 
   1358  1.1  tron <div class="handler">
   1359  1.1  tron <pre class="setter" id="XML_SetCdataSectionHandler">
   1360  1.1  tron void XMLCALL
   1361  1.1  tron XML_SetCdataSectionHandler(XML_Parser p,
   1362  1.1  tron                            XML_StartCdataSectionHandler start,
   1363  1.1  tron                            XML_EndCdataSectionHandler end)
   1364  1.1  tron </pre>
   1365  1.1  tron <p>Sets both CDATA section handlers with one call.</p>
   1366  1.1  tron </div>
   1367  1.1  tron 
   1368  1.1  tron <div class="handler">
   1369  1.1  tron <pre class="setter" id="XML_SetDefaultHandler">
   1370  1.1  tron void XMLCALL
   1371  1.1  tron XML_SetDefaultHandler(XML_Parser p,
   1372  1.1  tron                       XML_DefaultHandler hndl)
   1373  1.1  tron </pre>
   1374  1.1  tron <pre class="signature">
   1375  1.1  tron typedef void
   1376  1.1  tron (XMLCALL *XML_DefaultHandler)(void *userData,
   1377  1.1  tron                               const XML_Char *s,
   1378  1.1  tron                               int len);
   1379  1.1  tron </pre>
   1380  1.1  tron 
   1381  1.1  tron <p>Sets a handler for any characters in the document which wouldn't
   1382  1.1  tron otherwise be handled. This includes both data for which no handlers
   1383  1.1  tron can be set (like some kinds of DTD declarations) and data which could
   1384  1.1  tron be reported but which currently has no handler set.  The characters
   1385  1.1  tron are passed exactly as they were present in the XML document except
   1386  1.1  tron that they will be encoded in UTF-8 or UTF-16. Line boundaries are not
   1387  1.1  tron normalized. Note that a byte order mark character is not passed to the
   1388  1.1  tron default handler. There are no guarantees about how characters are
   1389  1.1  tron divided between calls to the default handler: for example, a comment
   1390  1.1  tron might be split between multiple calls.  Setting the handler with
   1391  1.1  tron this call has the side effect of turning off expansion of references
   1392  1.1  tron to internally defined general entities. Instead these references are
   1393  1.1  tron passed to the default handler.</p>
   1394  1.1  tron 
   1395  1.1  tron <p>See also <code><a
   1396  1.1  tron href="#XML_DefaultCurrent">XML_DefaultCurrent</a></code>.</p>
   1397  1.1  tron </div>
   1398  1.1  tron 
   1399  1.1  tron <div class="handler">
   1400  1.1  tron <pre class="setter" id="XML_SetDefaultHandlerExpand">
   1401  1.1  tron void XMLCALL
   1402  1.1  tron XML_SetDefaultHandlerExpand(XML_Parser p,
   1403  1.1  tron                             XML_DefaultHandler hndl)
   1404  1.1  tron </pre>
   1405  1.1  tron <pre class="signature">
   1406  1.1  tron typedef void
   1407  1.1  tron (XMLCALL *XML_DefaultHandler)(void *userData,
   1408  1.1  tron                               const XML_Char *s,
   1409  1.1  tron                               int len);
   1410  1.1  tron </pre>
   1411  1.1  tron <p>This sets a default handler, but doesn't inhibit the expansion of
   1412  1.1  tron internal entity references.  The entity reference will not be passed
   1413  1.1  tron to the default handler.</p>
   1414  1.1  tron 
   1415  1.1  tron <p>See also <code><a
   1416  1.1  tron href="#XML_DefaultCurrent">XML_DefaultCurrent</a></code>.</p>
   1417  1.1  tron </div>
   1418  1.1  tron 
   1419  1.1  tron <div class="handler">
   1420  1.1  tron <pre class="setter" id="XML_SetExternalEntityRefHandler">
   1421  1.1  tron void XMLCALL
   1422  1.1  tron XML_SetExternalEntityRefHandler(XML_Parser p,
   1423  1.1  tron                                 XML_ExternalEntityRefHandler hndl)
   1424  1.1  tron </pre>
   1425  1.1  tron <pre class="signature">
   1426  1.1  tron typedef int
   1427  1.1  tron (XMLCALL *XML_ExternalEntityRefHandler)(XML_Parser p,
   1428  1.1  tron                                         const XML_Char *context,
   1429  1.1  tron                                         const XML_Char *base,
   1430  1.1  tron                                         const XML_Char *systemId,
   1431  1.1  tron                                         const XML_Char *publicId);
   1432  1.1  tron </pre>
   1433  1.1  tron <p>Set an external entity reference handler. This handler is also
   1434  1.1  tron called for processing an external DTD subset if parameter entity parsing
   1435  1.1  tron is in effect. (See <a href="#XML_SetParamEntityParsing">
   1436  1.1  tron <code>XML_SetParamEntityParsing</code></a>.)</p>
   1437  1.1  tron 
   1438  1.1  tron <p>The <code>context</code> parameter specifies the parsing context in
   1439  1.1  tron the format expected by the <code>context</code> argument to <code><a
   1440  1.1  tron href="#XML_ExternalEntityParserCreate"
   1441  1.1  tron >XML_ExternalEntityParserCreate</a></code>.  <code>code</code> is
   1442  1.1  tron valid only until the handler returns, so if the referenced entity is
   1443  1.1  tron to be parsed later, it must be copied.  <code>context</code> is NULL
   1444  1.1  tron only when the entity is a parameter entity, which is how one can
   1445  1.1  tron differentiate between general and parameter entities.</p>
   1446  1.1  tron 
   1447  1.1  tron <p>The <code>base</code> parameter is the base to use for relative
   1448  1.1  tron system identifiers.  It is set by <code><a
   1449  1.1  tron href="#XML_SetBase">XML_SetBase</a></code> and may be NULL. The
   1450  1.1  tron <code>publicId</code> parameter is the public id given in the entity
   1451  1.1  tron declaration and may be NULL.  <code>systemId</code> is the system
   1452  1.1  tron identifier specified in the entity declaration and is never NULL.</p>
   1453  1.1  tron 
   1454  1.1  tron <p>There are a couple of ways in which this handler differs from
   1455  1.1  tron others.  First, this handler returns a status indicator (an
   1456  1.1  tron integer). <code>XML_STATUS_OK</code> should be returned for successful
   1457  1.1  tron handling of the external entity reference.  Returning
   1458  1.1  tron <code>XML_STATUS_ERROR</code> indicates failure, and causes the
   1459  1.1  tron calling parser to return an
   1460  1.1  tron <code>XML_ERROR_EXTERNAL_ENTITY_HANDLING</code> error.</p>
   1461  1.1  tron 
   1462  1.1  tron <p>Second, instead of having the user data as its first argument, it
   1463  1.1  tron receives the parser that encountered the entity reference. This, along
   1464  1.1  tron with the context parameter, may be used as arguments to a call to
   1465  1.1  tron <code><a href= "#XML_ExternalEntityParserCreate"
   1466  1.1  tron >XML_ExternalEntityParserCreate</a></code>.  Using the returned
   1467  1.1  tron parser, the body of the external entity can be recursively parsed.</p>
   1468  1.1  tron 
   1469  1.1  tron <p>Since this handler may be called recursively, it should not be saving
   1470  1.1  tron information into global or static variables.</p>
   1471  1.1  tron </div>
   1472  1.1  tron 
   1473  1.1  tron <pre class="fcndec" id="XML_SetExternalEntityRefHandlerArg">
   1474  1.1  tron void XMLCALL
   1475  1.1  tron XML_SetExternalEntityRefHandlerArg(XML_Parser p,
   1476  1.1  tron                                    void *arg)
   1477  1.1  tron </pre>
   1478  1.1  tron <div class="fcndef">
   1479  1.1  tron <p>Set the argument passed to the ExternalEntityRefHandler.  If
   1480  1.1  tron <code>arg</code> is not NULL, it is the new value passed to the
   1481  1.1  tron handler set using <code><a href="#XML_SetExternalEntityRefHandler"
   1482  1.1  tron >XML_SetExternalEntityRefHandler</a></code>; if <code>arg</code> is
   1483  1.1  tron NULL, the argument passed to the handler function will be the parser
   1484  1.1  tron object itself.</p>
   1485  1.1  tron 
   1486  1.1  tron <p><strong>Note:</strong>
   1487  1.1  tron The type of <code>arg</code> and the type of the first argument to the
   1488  1.1  tron ExternalEntityRefHandler do not match.  This function takes a
   1489  1.1  tron <code>void *</code> to be passed to the handler, while the handler
   1490  1.1  tron accepts an <code>XML_Parser</code>.  This is a historical accident,
   1491  1.1  tron but will not be corrected before Expat 2.0 (at the earliest) to avoid
   1492  1.1  tron causing compiler warnings for code that's known to work with this
   1493  1.1  tron API.  It is the responsibility of the application code to know the
   1494  1.1  tron actual type of the argument passed to the handler and to manage it
   1495  1.1  tron properly.</p>
   1496  1.1  tron </div>
   1497  1.1  tron 
   1498  1.1  tron <div class="handler">
   1499  1.1  tron <pre class="setter" id="XML_SetSkippedEntityHandler">
   1500  1.1  tron void XMLCALL
   1501  1.1  tron XML_SetSkippedEntityHandler(XML_Parser p,
   1502  1.1  tron                             XML_SkippedEntityHandler handler)
   1503  1.1  tron </pre>
   1504  1.1  tron <pre class="signature">
   1505  1.1  tron typedef void
   1506  1.1  tron (XMLCALL *XML_SkippedEntityHandler)(void *userData,
   1507  1.1  tron                                     const XML_Char *entityName,
   1508  1.1  tron                                     int is_parameter_entity);
   1509  1.1  tron </pre>
   1510  1.1  tron <p>Set a skipped entity handler. This is called in two situations:</p>
   1511  1.1  tron <ol>
   1512  1.1  tron    <li>An entity reference is encountered for which no declaration
   1513  1.1  tron        has been read <em>and</em> this is not an error.</li>
   1514  1.1  tron    <li>An internal entity reference is read, but not expanded, because
   1515  1.1  tron        <a href="#XML_SetDefaultHandler"><code>XML_SetDefaultHandler</code></a>
   1516  1.1  tron 	   has been called.</li>
   1517  1.1  tron </ol>
   1518  1.1  tron <p>The <code>is_parameter_entity</code> argument will be non-zero for
   1519  1.1  tron a parameter entity and zero for a general entity.</p> <p>Note: skipped
   1520  1.1  tron parameter entities in declarations and skipped general entities in
   1521  1.1  tron attribute values cannot be reported, because the event would be out of
   1522  1.1  tron sync with the reporting of the declarations or attribute values</p>
   1523  1.1  tron </div>
   1524  1.1  tron 
   1525  1.1  tron <div class="handler">
   1526  1.1  tron <pre class="setter" id="XML_SetUnknownEncodingHandler">
   1527  1.1  tron void XMLCALL
   1528  1.1  tron XML_SetUnknownEncodingHandler(XML_Parser p,
   1529  1.1  tron                               XML_UnknownEncodingHandler enchandler,
   1530  1.1  tron 			      void *encodingHandlerData)
   1531  1.1  tron </pre>
   1532  1.1  tron <pre class="signature">
   1533  1.1  tron typedef int
   1534  1.1  tron (XMLCALL *XML_UnknownEncodingHandler)(void *encodingHandlerData,
   1535  1.1  tron                                       const XML_Char *name,
   1536  1.1  tron                                       XML_Encoding *info);
   1537  1.1  tron 
   1538  1.1  tron typedef struct {
   1539  1.1  tron   int map[256];
   1540  1.1  tron   void *data;
   1541  1.1  tron   int (XMLCALL *convert)(void *data, const char *s);
   1542  1.1  tron   void (XMLCALL *release)(void *data);
   1543  1.1  tron } XML_Encoding;
   1544  1.1  tron </pre>
   1545  1.1  tron <p>Set a handler to deal with encodings other than the <a
   1546  1.1  tron href="#builtin_encodings">built in set</a>. This should be done before
   1547  1.1  tron <code><a href= "#XML_Parse" >XML_Parse</a></code> or <code><a href=
   1548  1.1  tron "#XML_ParseBuffer" >XML_ParseBuffer</a></code> have been called on the
   1549  1.1  tron given parser.</p> <p>If the handler knows how to deal with an encoding
   1550  1.1  tron with the given name, it should fill in the <code>info</code> data
   1551  1.1  tron structure and return <code>XML_STATUS_OK</code>. Otherwise it
   1552  1.1  tron should return <code>XML_STATUS_ERROR</code>. The handler will be called
   1553  1.1  tron at most once per parsed (external) entity. The optional application
   1554  1.1  tron data pointer <code>encodingHandlerData</code> will be passed back to
   1555  1.1  tron the handler.</p>
   1556  1.1  tron 
   1557  1.1  tron <p>The map array contains information for every possible possible leading
   1558  1.1  tron byte in a byte sequence. If the corresponding value is &gt;= 0, then it's
   1559  1.1  tron a single byte sequence and the byte encodes that Unicode value. If the
   1560  1.1  tron value is -1, then that byte is invalid as the initial byte in a sequence.
   1561  1.1  tron If the value is -n, where n is an integer &gt; 1, then n is the number of
   1562  1.1  tron bytes in the sequence and the actual conversion is accomplished by a
   1563  1.1  tron call to the function pointed at by convert. This function may return -1
   1564  1.1  tron if the sequence itself is invalid. The convert pointer may be null if
   1565  1.1  tron there are only single byte codes. The data parameter passed to the convert
   1566  1.1  tron function is the data pointer from <code>XML_Encoding</code>. The
   1567  1.1  tron string s is <em>NOT</em> nul-terminated and points at the sequence of
   1568  1.1  tron bytes to be converted.</p>
   1569  1.1  tron 
   1570  1.1  tron <p>The function pointed at by <code>release</code> is called by the
   1571  1.1  tron parser when it is finished with the encoding. It may be NULL.</p>
   1572  1.1  tron </div>
   1573  1.1  tron 
   1574  1.1  tron <div class="handler">
   1575  1.1  tron <pre class="setter" id="XML_SetStartNamespaceDeclHandler">
   1576  1.1  tron void XMLCALL
   1577  1.1  tron XML_SetStartNamespaceDeclHandler(XML_Parser p,
   1578  1.1  tron 			         XML_StartNamespaceDeclHandler start);
   1579  1.1  tron </pre>
   1580  1.1  tron <pre class="signature">
   1581  1.1  tron typedef void
   1582  1.1  tron (XMLCALL *XML_StartNamespaceDeclHandler)(void *userData,
   1583  1.1  tron                                          const XML_Char *prefix,
   1584  1.1  tron                                          const XML_Char *uri);
   1585  1.1  tron </pre>
   1586  1.1  tron <p>Set a handler to be called when a namespace is declared. Namespace
   1587  1.1  tron declarations occur inside start tags. But the namespace declaration start
   1588  1.1  tron handler is called before the start tag handler for each namespace declared
   1589  1.1  tron in that start tag.</p>
   1590  1.1  tron </div>
   1591  1.1  tron 
   1592  1.1  tron <div class="handler">
   1593  1.1  tron <pre class="setter" id="XML_SetEndNamespaceDeclHandler">
   1594  1.1  tron void XMLCALL
   1595  1.1  tron XML_SetEndNamespaceDeclHandler(XML_Parser p,
   1596  1.1  tron 			       XML_EndNamespaceDeclHandler end);
   1597  1.1  tron </pre>
   1598  1.1  tron <pre class="signature">
   1599  1.1  tron typedef void
   1600  1.1  tron (XMLCALL *XML_EndNamespaceDeclHandler)(void *userData,
   1601  1.1  tron                                        const XML_Char *prefix);
   1602  1.1  tron </pre>
   1603  1.1  tron <p>Set a handler to be called when leaving the scope of a namespace
   1604  1.1  tron declaration. This will be called, for each namespace declaration,
   1605  1.1  tron after the handler for the end tag of the element in which the
   1606  1.1  tron namespace was declared.</p>
   1607  1.1  tron </div>
   1608  1.1  tron 
   1609  1.1  tron <div class="handler">
   1610  1.1  tron <pre class="setter" id="XML_SetNamespaceDeclHandler">
   1611  1.1  tron void XMLCALL
   1612  1.1  tron XML_SetNamespaceDeclHandler(XML_Parser p,
   1613  1.1  tron                             XML_StartNamespaceDeclHandler start,
   1614  1.1  tron                             XML_EndNamespaceDeclHandler end)
   1615  1.1  tron </pre>
   1616  1.1  tron <p>Sets both namespace declaration handlers with a single call.</p>
   1617  1.1  tron </div>
   1618  1.1  tron 
   1619  1.1  tron <div class="handler">
   1620  1.1  tron <pre class="setter" id="XML_SetXmlDeclHandler">
   1621  1.1  tron void XMLCALL
   1622  1.1  tron XML_SetXmlDeclHandler(XML_Parser p,
   1623  1.1  tron 		      XML_XmlDeclHandler xmldecl);
   1624  1.1  tron </pre>
   1625  1.1  tron <pre class="signature">
   1626  1.1  tron typedef void
   1627  1.1  tron (XMLCALL *XML_XmlDeclHandler)(void            *userData,
   1628  1.1  tron                               const XML_Char  *version,
   1629  1.1  tron                               const XML_Char  *encoding,
   1630  1.1  tron                               int             standalone);
   1631  1.1  tron </pre>
   1632  1.1  tron <p>Sets a handler that is called for XML declarations and also for
   1633  1.1  tron text declarations discovered in external entities. The way to
   1634  1.1  tron distinguish is that the <code>version</code> parameter will be NULL
   1635  1.1  tron for text declarations. The <code>encoding</code> parameter may be NULL
   1636  1.1  tron for an XML declaration. The <code>standalone</code> argument will
   1637  1.1  tron contain -1, 0, or 1 indicating respectively that there was no
   1638  1.1  tron standalone parameter in the declaration, that it was given as no, or
   1639  1.1  tron that it was given as yes.</p>
   1640  1.1  tron </div>
   1641  1.1  tron 
   1642  1.1  tron <div class="handler">
   1643  1.1  tron <pre class="setter" id="XML_SetStartDoctypeDeclHandler">
   1644  1.1  tron void XMLCALL
   1645  1.1  tron XML_SetStartDoctypeDeclHandler(XML_Parser p,
   1646  1.1  tron 			       XML_StartDoctypeDeclHandler start);
   1647  1.1  tron </pre>
   1648  1.1  tron <pre class="signature">
   1649  1.1  tron typedef void
   1650  1.1  tron (XMLCALL *XML_StartDoctypeDeclHandler)(void           *userData,
   1651  1.1  tron                                        const XML_Char *doctypeName,
   1652  1.1  tron                                        const XML_Char *sysid,
   1653  1.1  tron                                        const XML_Char *pubid,
   1654  1.1  tron                                        int            has_internal_subset);
   1655  1.1  tron </pre>
   1656  1.1  tron <p>Set a handler that is called at the start of a DOCTYPE declaration,
   1657  1.1  tron before any external or internal subset is parsed. Both <code>sysid</code>
   1658  1.1  tron and <code>pubid</code> may be NULL. The <code>has_internal_subset</code>
   1659  1.1  tron will be non-zero if the DOCTYPE declaration has an internal subset.</p>
   1660  1.1  tron </div>
   1661  1.1  tron 
   1662  1.1  tron <div class="handler">
   1663  1.1  tron <pre class="setter" id="XML_SetEndDoctypeDeclHandler">
   1664  1.1  tron void XMLCALL
   1665  1.1  tron XML_SetEndDoctypeDeclHandler(XML_Parser p,
   1666  1.1  tron 			     XML_EndDoctypeDeclHandler end);
   1667  1.1  tron </pre>
   1668  1.1  tron <pre class="signature">
   1669  1.1  tron typedef void
   1670  1.1  tron (XMLCALL *XML_EndDoctypeDeclHandler)(void *userData);
   1671  1.1  tron </pre>
   1672  1.1  tron <p>Set a handler that is called at the end of a DOCTYPE declaration,
   1673  1.1  tron after parsing any external subset.</p>
   1674  1.1  tron </div>
   1675  1.1  tron 
   1676  1.1  tron <div class="handler">
   1677  1.1  tron <pre class="setter" id="XML_SetDoctypeDeclHandler">
   1678  1.1  tron void XMLCALL
   1679  1.1  tron XML_SetDoctypeDeclHandler(XML_Parser p,
   1680  1.1  tron 			  XML_StartDoctypeDeclHandler start,
   1681  1.1  tron 			  XML_EndDoctypeDeclHandler end);
   1682  1.1  tron </pre>
   1683  1.1  tron <p>Set both doctype handlers with one call.</p>
   1684  1.1  tron </div>
   1685  1.1  tron 
   1686  1.1  tron <div class="handler">
   1687  1.1  tron <pre class="setter" id="XML_SetElementDeclHandler">
   1688  1.1  tron void XMLCALL
   1689  1.1  tron XML_SetElementDeclHandler(XML_Parser p,
   1690  1.1  tron 			  XML_ElementDeclHandler eldecl);
   1691  1.1  tron </pre>
   1692  1.1  tron <pre class="signature">
   1693  1.1  tron typedef void
   1694  1.1  tron (XMLCALL *XML_ElementDeclHandler)(void *userData,
   1695  1.1  tron                                   const XML_Char *name,
   1696  1.1  tron                                   XML_Content *model);
   1697  1.1  tron </pre>
   1698  1.1  tron <pre class="signature">
   1699  1.1  tron enum XML_Content_Type {
   1700  1.1  tron   XML_CTYPE_EMPTY = 1,
   1701  1.1  tron   XML_CTYPE_ANY,
   1702  1.1  tron   XML_CTYPE_MIXED,
   1703  1.1  tron   XML_CTYPE_NAME,
   1704  1.1  tron   XML_CTYPE_CHOICE,
   1705  1.1  tron   XML_CTYPE_SEQ
   1706  1.1  tron };
   1707  1.1  tron 
   1708  1.1  tron enum XML_Content_Quant {
   1709  1.1  tron   XML_CQUANT_NONE,
   1710  1.1  tron   XML_CQUANT_OPT,
   1711  1.1  tron   XML_CQUANT_REP,
   1712  1.1  tron   XML_CQUANT_PLUS
   1713  1.1  tron };
   1714  1.1  tron 
   1715  1.1  tron typedef struct XML_cp XML_Content;
   1716  1.1  tron 
   1717  1.1  tron struct XML_cp {
   1718  1.1  tron   enum XML_Content_Type		type;
   1719  1.1  tron   enum XML_Content_Quant	quant;
   1720  1.1  tron   const XML_Char *		name;
   1721  1.1  tron   unsigned int			numchildren;
   1722  1.1  tron   XML_Content *			children;
   1723  1.1  tron };
   1724  1.1  tron </pre>
   1725  1.1  tron <p>Sets a handler for element declarations in a DTD. The handler gets
   1726  1.1  tron called with the name of the element in the declaration and a pointer
   1727  1.1  tron to a structure that contains the element model. It is the
   1728  1.1  tron application's responsibility to free this data structure using
   1729  1.1  tron <code><a href="#XML_FreeContentModel"
   1730  1.1  tron >XML_FreeContentModel</a></code>.</p>
   1731  1.1  tron 
   1732  1.1  tron <p>The <code>model</code> argument is the root of a tree of
   1733  1.1  tron <code>XML_Content</code> nodes. If <code>type</code> equals
   1734  1.1  tron <code>XML_CTYPE_EMPTY</code> or <code>XML_CTYPE_ANY</code>, then
   1735  1.1  tron <code>quant</code> will be <code>XML_CQUANT_NONE</code>, and the other
   1736  1.1  tron fields will be zero or NULL.  If <code>type</code> is
   1737  1.1  tron <code>XML_CTYPE_MIXED</code>, then <code>quant</code> will be
   1738  1.1  tron <code>XML_CQUANT_NONE</code> or <code>XML_CQUANT_REP</code> and
   1739  1.1  tron <code>numchildren</code> will contain the number of elements that are
   1740  1.1  tron allowed to be mixed in and <code>children</code> points to an array of
   1741  1.1  tron <code>XML_Content</code> structures that will all have type
   1742  1.1  tron XML_CTYPE_NAME with no quantification.  Only the root node can be type
   1743  1.1  tron <code>XML_CTYPE_EMPTY</code>, <code>XML_CTYPE_ANY</code>, or
   1744  1.1  tron <code>XML_CTYPE_MIXED</code>.</p>
   1745  1.1  tron 
   1746  1.1  tron <p>For type <code>XML_CTYPE_NAME</code>, the <code>name</code> field
   1747  1.1  tron points to the name and the <code>numchildren</code> and
   1748  1.1  tron <code>children</code> fields will be zero and NULL. The
   1749  1.1  tron <code>quant</code> field will indicate any quantifiers placed on the
   1750  1.1  tron name.</p>
   1751  1.1  tron 
   1752  1.1  tron <p>Types <code>XML_CTYPE_CHOICE</code> and <code>XML_CTYPE_SEQ</code>
   1753  1.1  tron indicate a choice or sequence respectively. The
   1754  1.1  tron <code>numchildren</code> field indicates how many nodes in the choice
   1755  1.1  tron or sequence and <code>children</code> points to the nodes.</p>
   1756  1.1  tron </div>
   1757  1.1  tron 
   1758  1.1  tron <div class="handler">
   1759  1.1  tron <pre class="setter" id="XML_SetAttlistDeclHandler">
   1760  1.1  tron void XMLCALL
   1761  1.1  tron XML_SetAttlistDeclHandler(XML_Parser p,
   1762  1.1  tron                           XML_AttlistDeclHandler attdecl);
   1763  1.1  tron </pre>
   1764  1.1  tron <pre class="signature">
   1765  1.1  tron typedef void
   1766  1.1  tron (XMLCALL *XML_AttlistDeclHandler)(void           *userData,
   1767  1.1  tron                                   const XML_Char *elname,
   1768  1.1  tron                                   const XML_Char *attname,
   1769  1.1  tron                                   const XML_Char *att_type,
   1770  1.1  tron                                   const XML_Char *dflt,
   1771  1.1  tron                                   int            isrequired);
   1772  1.1  tron </pre>
   1773  1.1  tron <p>Set a handler for attlist declarations in the DTD. This handler is
   1774  1.1  tron called for <em>each</em> attribute. So a single attlist declaration
   1775  1.1  tron with multiple attributes declared will generate multiple calls to this
   1776  1.1  tron handler. The <code>elname</code> parameter returns the name of the
   1777  1.1  tron element for which the attribute is being declared. The attribute name
   1778  1.1  tron is in the <code>attname</code> parameter. The attribute type is in the
   1779  1.1  tron <code>att_type</code> parameter.  It is the string representing the
   1780  1.1  tron type in the declaration with whitespace removed.</p>
   1781  1.1  tron 
   1782  1.1  tron <p>The <code>dflt</code> parameter holds the default value. It will be
   1783  1.1  tron NULL in the case of "#IMPLIED" or "#REQUIRED" attributes. You can
   1784  1.1  tron distinguish these two cases by checking the <code>isrequired</code>
   1785  1.1  tron parameter, which will be true in the case of "#REQUIRED" attributes.
   1786  1.1  tron Attributes which are "#FIXED" will have also have a true
   1787  1.1  tron <code>isrequired</code>, but they will have the non-NULL fixed value
   1788  1.1  tron in the <code>dflt</code> parameter.</p>
   1789  1.1  tron </div>
   1790  1.1  tron 
   1791  1.1  tron <div class="handler">
   1792  1.1  tron <pre class="setter" id="XML_SetEntityDeclHandler">
   1793  1.1  tron void XMLCALL
   1794  1.1  tron XML_SetEntityDeclHandler(XML_Parser p,
   1795  1.1  tron 			 XML_EntityDeclHandler handler);
   1796  1.1  tron </pre>
   1797  1.1  tron <pre class="signature">
   1798  1.1  tron typedef void
   1799  1.1  tron (XMLCALL *XML_EntityDeclHandler)(void           *userData,
   1800  1.1  tron                                  const XML_Char *entityName,
   1801  1.1  tron                                  int            is_parameter_entity,
   1802  1.1  tron                                  const XML_Char *value,
   1803  1.1  tron                                  int            value_length, 
   1804  1.1  tron                                  const XML_Char *base,
   1805  1.1  tron                                  const XML_Char *systemId,
   1806  1.1  tron                                  const XML_Char *publicId,
   1807  1.1  tron                                  const XML_Char *notationName);
   1808  1.1  tron </pre>
   1809  1.1  tron <p>Sets a handler that will be called for all entity declarations.
   1810  1.1  tron The <code>is_parameter_entity</code> argument will be non-zero in the
   1811  1.1  tron case of parameter entities and zero otherwise.</p>
   1812  1.1  tron 
   1813  1.1  tron <p>For internal entities (<code>&lt;!ENTITY foo "bar"&gt;</code>),
   1814  1.1  tron <code>value</code> will be non-NULL and <code>systemId</code>,
   1815  1.1  tron <code>publicId</code>, and <code>notationName</code> will all be NULL.
   1816  1.1  tron The value string is <em>not</em> NULL terminated; the length is
   1817  1.1  tron provided in the <code>value_length</code> parameter. Do not use
   1818  1.1  tron <code>value_length</code> to test for internal entities, since it is
   1819  1.1  tron legal to have zero-length values. Instead check for whether or not
   1820  1.1  tron <code>value</code> is NULL.</p> <p>The <code>notationName</code>
   1821  1.1  tron argument will have a non-NULL value only for unparsed entity
   1822  1.1  tron declarations.</p>
   1823  1.1  tron </div>
   1824  1.1  tron 
   1825  1.1  tron <div class="handler">
   1826  1.1  tron <pre class="setter" id="XML_SetUnparsedEntityDeclHandler">
   1827  1.1  tron void XMLCALL
   1828  1.1  tron XML_SetUnparsedEntityDeclHandler(XML_Parser p,
   1829  1.1  tron                                  XML_UnparsedEntityDeclHandler h)
   1830  1.1  tron </pre>
   1831  1.1  tron <pre class="signature">
   1832  1.1  tron typedef void
   1833  1.1  tron (XMLCALL *XML_UnparsedEntityDeclHandler)(void *userData,
   1834  1.1  tron                                          const XML_Char *entityName, 
   1835  1.1  tron                                          const XML_Char *base,
   1836  1.1  tron                                          const XML_Char *systemId,
   1837  1.1  tron                                          const XML_Char *publicId,
   1838  1.1  tron                                          const XML_Char *notationName);
   1839  1.1  tron </pre>
   1840  1.1  tron <p>Set a handler that receives declarations of unparsed entities. These
   1841  1.1  tron are entity declarations that have a notation (NDATA) field:</p>
   1842  1.1  tron 
   1843  1.1  tron <div id="eg"><pre>
   1844  1.1  tron &lt;!ENTITY logo SYSTEM "images/logo.gif" NDATA gif&gt;
   1845  1.1  tron </pre></div>
   1846  1.1  tron <p>This handler is obsolete and is provided for backwards
   1847  1.1  tron compatibility.  Use instead <a href= "#XML_SetEntityDeclHandler"
   1848  1.1  tron >XML_SetEntityDeclHandler</a>.</p>
   1849  1.1  tron </div>
   1850  1.1  tron 
   1851  1.1  tron <div class="handler">
   1852  1.1  tron <pre class="setter" id="XML_SetNotationDeclHandler">
   1853  1.1  tron void XMLCALL
   1854  1.1  tron XML_SetNotationDeclHandler(XML_Parser p,
   1855  1.1  tron                            XML_NotationDeclHandler h)
   1856  1.1  tron </pre>
   1857  1.1  tron <pre class="signature">
   1858  1.1  tron typedef void
   1859  1.1  tron (XMLCALL *XML_NotationDeclHandler)(void *userData, 
   1860  1.1  tron                                    const XML_Char *notationName,
   1861  1.1  tron                                    const XML_Char *base,
   1862  1.1  tron                                    const XML_Char *systemId,
   1863  1.1  tron                                    const XML_Char *publicId);
   1864  1.1  tron </pre>
   1865  1.1  tron <p>Set a handler that receives notation declarations.</p>
   1866  1.1  tron </div>
   1867  1.1  tron 
   1868  1.1  tron <div class="handler">
   1869  1.1  tron <pre class="setter" id="XML_SetNotStandaloneHandler">
   1870  1.1  tron void XMLCALL
   1871  1.1  tron XML_SetNotStandaloneHandler(XML_Parser p,
   1872  1.1  tron                             XML_NotStandaloneHandler h)
   1873  1.1  tron </pre>
   1874  1.1  tron <pre class="signature">
   1875  1.1  tron typedef int 
   1876  1.1  tron (XMLCALL *XML_NotStandaloneHandler)(void *userData);
   1877  1.1  tron </pre>
   1878  1.1  tron <p>Set a handler that is called if the document is not "standalone".
   1879  1.1  tron This happens when there is an external subset or a reference to a
   1880  1.1  tron parameter entity, but does not have standalone set to "yes" in an XML
   1881  1.1  tron declaration.  If this handler returns <code>XML_STATUS_ERROR</code>,
   1882  1.1  tron then the parser will throw an <code>XML_ERROR_NOT_STANDALONE</code>
   1883  1.1  tron error.</p>
   1884  1.1  tron </div>
   1885  1.1  tron 
   1886  1.1  tron <h3><a name="position">Parse position and error reporting functions</a></h3>
   1887  1.1  tron 
   1888  1.1  tron <p>These are the functions you'll want to call when the parse
   1889  1.1  tron functions return <code>XML_STATUS_ERROR</code> (a parse error has
   1890  1.1  tron occurred), although the position reporting functions are useful outside
   1891  1.1  tron of errors. The position reported is the byte position (in the original
   1892  1.1  tron document or entity encoding) of the first of the sequence of
   1893  1.1  tron characters that generated the current event (or the error that caused
   1894  1.1  tron the parse functions to return <code>XML_STATUS_ERROR</code>.)  The
   1895  1.1  tron exceptions are callbacks trigged by declarations in the document
   1896  1.1  tron prologue, in which case they exact position reported is somewhere in the
   1897  1.1  tron relevant markup, but not necessarily as meaningful as for other
   1898  1.1  tron events.</p>
   1899  1.1  tron 
   1900  1.1  tron <p>The position reporting functions are accurate only outside of the
   1901  1.1  tron DTD.  In other words, they usually return bogus information when
   1902  1.1  tron called from within a DTD declaration handler.</p>
   1903  1.1  tron 
   1904  1.1  tron <pre class="fcndec" id="XML_GetErrorCode">
   1905  1.1  tron enum XML_Error XMLCALL
   1906  1.1  tron XML_GetErrorCode(XML_Parser p);
   1907  1.1  tron </pre>
   1908  1.1  tron <div class="fcndef">
   1909  1.1  tron Return what type of error has occurred.
   1910  1.1  tron </div>
   1911  1.1  tron 
   1912  1.1  tron <pre class="fcndec" id="XML_ErrorString">
   1913  1.1  tron const XML_LChar * XMLCALL
   1914  1.1  tron XML_ErrorString(enum XML_Error code);
   1915  1.1  tron </pre>
   1916  1.1  tron <div class="fcndef">
   1917  1.1  tron Return a string describing the error corresponding to code.
   1918  1.1  tron The code should be one of the enums that can be returned from
   1919  1.1  tron <code><a href= "#XML_GetErrorCode" >XML_GetErrorCode</a></code>.
   1920  1.1  tron </div>
   1921  1.1  tron 
   1922  1.1  tron <pre class="fcndec" id="XML_GetCurrentByteIndex">
   1923  1.1  tron XML_Index XMLCALL
   1924  1.1  tron XML_GetCurrentByteIndex(XML_Parser p);
   1925  1.1  tron </pre>
   1926  1.1  tron <div class="fcndef">
   1927  1.1  tron Return the byte offset of the position.  This always corresponds to
   1928  1.1  tron the values returned by <code><a href= "#XML_GetCurrentLineNumber"
   1929  1.1  tron >XML_GetCurrentLineNumber</a></code> and <code><a href=
   1930  1.1  tron "#XML_GetCurrentColumnNumber" >XML_GetCurrentColumnNumber</a></code>.
   1931  1.1  tron </div>
   1932  1.1  tron 
   1933  1.1  tron <pre class="fcndec" id="XML_GetCurrentLineNumber">
   1934  1.1  tron XML_Size XMLCALL
   1935  1.1  tron XML_GetCurrentLineNumber(XML_Parser p);
   1936  1.1  tron </pre>
   1937  1.1  tron <div class="fcndef">
   1938  1.1  tron Return the line number of the position.  The first line is reported as
   1939  1.1  tron <code>1</code>.
   1940  1.1  tron </div>
   1941  1.1  tron 
   1942  1.1  tron <pre class="fcndec" id="XML_GetCurrentColumnNumber">
   1943  1.1  tron XML_Size XMLCALL
   1944  1.1  tron XML_GetCurrentColumnNumber(XML_Parser p);
   1945  1.1  tron </pre>
   1946  1.1  tron <div class="fcndef">
   1947  1.1  tron Return the offset, from the beginning of the current line, of
   1948  1.1  tron the position.
   1949  1.1  tron </div>
   1950  1.1  tron 
   1951  1.1  tron <pre class="fcndec" id="XML_GetCurrentByteCount">
   1952  1.1  tron int XMLCALL
   1953  1.1  tron XML_GetCurrentByteCount(XML_Parser p);
   1954  1.1  tron </pre>
   1955  1.1  tron <div class="fcndef">
   1956  1.1  tron Return the number of bytes in the current event. Returns
   1957  1.1  tron <code>0</code> if the event is inside a reference to an internal
   1958  1.1  tron entity and for the end-tag event for empty element tags (the later can
   1959  1.1  tron be used to distinguish empty-element tags from empty elements using
   1960  1.1  tron separate start and end tags).
   1961  1.1  tron </div>
   1962  1.1  tron 
   1963  1.1  tron <pre class="fcndec" id="XML_GetInputContext">
   1964  1.1  tron const char * XMLCALL
   1965  1.1  tron XML_GetInputContext(XML_Parser p,
   1966  1.1  tron                     int *offset,
   1967  1.1  tron                     int *size);
   1968  1.1  tron </pre>
   1969  1.1  tron <div class="fcndef">
   1970  1.1  tron 
   1971  1.1  tron <p>Returns the parser's input buffer, sets the integer pointed at by
   1972  1.1  tron <code>offset</code> to the offset within this buffer of the current
   1973  1.1  tron parse position, and set the integer pointed at by <code>size</code> to
   1974  1.1  tron the size of the returned buffer.</p>
   1975  1.1  tron 
   1976  1.1  tron <p>This should only be called from within a handler during an active
   1977  1.1  tron parse and the returned buffer should only be referred to from within
   1978  1.1  tron the handler that made the call. This input buffer contains the
   1979  1.1  tron untranslated bytes of the input.</p>
   1980  1.1  tron 
   1981  1.1  tron <p>Only a limited amount of context is kept, so if the event
   1982  1.1  tron triggering a call spans over a very large amount of input, the actual
   1983  1.1  tron parse position may be before the beginning of the buffer.</p>
   1984  1.1  tron 
   1985  1.1  tron <p>If <code>XML_CONTEXT_BYTES</code> is not defined, this will always
   1986  1.1  tron return NULL.</p>
   1987  1.1  tron </div>
   1988  1.1  tron 
   1989  1.1  tron <h3><a name="miscellaneous">Miscellaneous functions</a></h3>
   1990  1.1  tron 
   1991  1.1  tron <p>The functions in this section either obtain state information from
   1992  1.1  tron the parser or can be used to dynamicly set parser options.</p>
   1993  1.1  tron 
   1994  1.1  tron <pre class="fcndec" id="XML_SetUserData">
   1995  1.1  tron void XMLCALL
   1996  1.1  tron XML_SetUserData(XML_Parser p,
   1997  1.1  tron                 void *userData);
   1998  1.1  tron </pre>
   1999  1.1  tron <div class="fcndef">
   2000  1.1  tron This sets the user data pointer that gets passed to handlers.  It
   2001  1.1  tron overwrites any previous value for this pointer. Note that the
   2002  1.1  tron application is responsible for freeing the memory associated with
   2003  1.1  tron <code>userData</code> when it is finished with the parser. So if you
   2004  1.1  tron call this when there's already a pointer there, and you haven't freed
   2005  1.1  tron the memory associated with it, then you've probably just leaked
   2006  1.1  tron memory.
   2007  1.1  tron </div>
   2008  1.1  tron 
   2009  1.1  tron <pre class="fcndec" id="XML_GetUserData">
   2010  1.1  tron void * XMLCALL
   2011  1.1  tron XML_GetUserData(XML_Parser p);
   2012  1.1  tron </pre>
   2013  1.1  tron <div class="fcndef">
   2014  1.1  tron This returns the user data pointer that gets passed to handlers.
   2015  1.1  tron It is actually implemented as a macro.
   2016  1.1  tron </div>
   2017  1.1  tron 
   2018  1.1  tron <pre class="fcndec" id="XML_UseParserAsHandlerArg">
   2019  1.1  tron void XMLCALL
   2020  1.1  tron XML_UseParserAsHandlerArg(XML_Parser p);
   2021  1.1  tron </pre>
   2022  1.1  tron <div class="fcndef">
   2023  1.1  tron After this is called, handlers receive the parser in their
   2024  1.1  tron <code>userData</code> arguments.  The user data can still be obtained
   2025  1.1  tron using the <code><a href= "#XML_GetUserData"
   2026  1.1  tron >XML_GetUserData</a></code> function.
   2027  1.1  tron </div>
   2028  1.1  tron 
   2029  1.1  tron <pre class="fcndec" id="XML_SetBase">
   2030  1.1  tron enum XML_Status XMLCALL
   2031  1.1  tron XML_SetBase(XML_Parser p,
   2032  1.1  tron             const XML_Char *base);
   2033  1.1  tron </pre>
   2034  1.1  tron <div class="fcndef">
   2035  1.1  tron Set the base to be used for resolving relative URIs in system
   2036  1.1  tron identifiers.  The return value is <code>XML_STATUS_ERROR</code> if
   2037  1.1  tron there's no memory to store base, otherwise it's
   2038  1.1  tron <code>XML_STATUS_OK</code>.
   2039  1.1  tron </div>
   2040  1.1  tron 
   2041  1.1  tron <pre class="fcndec" id="XML_GetBase">
   2042  1.1  tron const XML_Char * XMLCALL
   2043  1.1  tron XML_GetBase(XML_Parser p);
   2044  1.1  tron </pre>
   2045  1.1  tron <div class="fcndef">
   2046  1.1  tron Return the base for resolving relative URIs.
   2047  1.1  tron </div>
   2048  1.1  tron 
   2049  1.1  tron <pre class="fcndec" id="XML_GetSpecifiedAttributeCount">
   2050  1.1  tron int XMLCALL
   2051  1.1  tron XML_GetSpecifiedAttributeCount(XML_Parser p);
   2052  1.1  tron </pre>
   2053  1.1  tron <div class="fcndef">
   2054  1.1  tron When attributes are reported to the start handler in the atts vector,
   2055  1.1  tron attributes that were explicitly set in the element occur before any
   2056  1.1  tron attributes that receive their value from default information in an
   2057  1.1  tron ATTLIST declaration. This function returns the number of attributes
   2058  1.1  tron that were explicitly set times two, thus giving the offset in the
   2059  1.1  tron <code>atts</code> array passed to the start tag handler of the first
   2060  1.1  tron attribute set due to defaults. It supplies information for the last
   2061  1.1  tron call to a start handler. If called inside a start handler, then that
   2062  1.1  tron means the current call.
   2063  1.1  tron </div>
   2064  1.1  tron 
   2065  1.1  tron <pre class="fcndec" id="XML_GetIdAttributeIndex">
   2066  1.1  tron int XMLCALL
   2067  1.1  tron XML_GetIdAttributeIndex(XML_Parser p);
   2068  1.1  tron </pre>
   2069  1.1  tron <div class="fcndef">
   2070  1.1  tron Returns the index of the ID attribute passed in the atts array in the
   2071  1.1  tron last call to <code><a href= "#XML_StartElementHandler"
   2072  1.1  tron >XML_StartElementHandler</a></code>, or -1 if there is no ID
   2073  1.1  tron attribute. If called inside a start handler, then that means the
   2074  1.1  tron current call.
   2075  1.1  tron </div>
   2076  1.1  tron 
   2077  1.1  tron <pre class="fcndec" id="XML_SetEncoding">
   2078  1.1  tron enum XML_Status XMLCALL
   2079  1.1  tron XML_SetEncoding(XML_Parser p,
   2080  1.1  tron                 const XML_Char *encoding);
   2081  1.1  tron </pre>
   2082  1.1  tron <div class="fcndef">
   2083  1.1  tron Set the encoding to be used by the parser. It is equivalent to
   2084  1.1  tron passing a non-null encoding argument to the parser creation functions.
   2085  1.1  tron It must not be called after <code><a href= "#XML_Parse"
   2086  1.1  tron >XML_Parse</a></code> or <code><a href= "#XML_ParseBuffer"
   2087  1.1  tron >XML_ParseBuffer</a></code> have been called on the given parser.
   2088  1.1  tron Returns <code>XML_STATUS_OK</code> on success or
   2089  1.1  tron <code>XML_STATUS_ERROR</code> on error.
   2090  1.1  tron </div>
   2091  1.1  tron 
   2092  1.1  tron <pre class="fcndec" id="XML_SetParamEntityParsing">
   2093  1.1  tron int XMLCALL
   2094  1.1  tron XML_SetParamEntityParsing(XML_Parser p,
   2095  1.1  tron                           enum XML_ParamEntityParsing code);
   2096  1.1  tron </pre>
   2097  1.1  tron <div class="fcndef">
   2098  1.1  tron This enables parsing of parameter entities, including the external
   2099  1.1  tron parameter entity that is the external DTD subset, according to
   2100  1.1  tron <code>code</code>.
   2101  1.1  tron The choices for <code>code</code> are:
   2102  1.1  tron <ul>
   2103  1.1  tron <li><code>XML_PARAM_ENTITY_PARSING_NEVER</code></li>
   2104  1.1  tron <li><code>XML_PARAM_ENTITY_PARSING_UNLESS_STANDALONE</code></li>
   2105  1.1  tron <li><code>XML_PARAM_ENTITY_PARSING_ALWAYS</code></li>
   2106  1.1  tron </ul>
   2107  1.1  tron </div>
   2108  1.1  tron 
   2109  1.1  tron <pre class="fcndec" id="XML_UseForeignDTD">
   2110  1.1  tron enum XML_Error XMLCALL
   2111  1.1  tron XML_UseForeignDTD(XML_Parser parser, XML_Bool useDTD);
   2112  1.1  tron </pre>
   2113  1.1  tron <div class="fcndef">
   2114  1.1  tron <p>This function allows an application to provide an external subset
   2115  1.1  tron for the document type declaration for documents which do not specify
   2116  1.1  tron an external subset of their own.  For documents which specify an
   2117  1.1  tron external subset in their DOCTYPE declaration, the application-provided
   2118  1.1  tron subset will be ignored.  If the document does not contain a DOCTYPE
   2119  1.1  tron declaration at all and <code>useDTD</code> is true, the
   2120  1.1  tron application-provided subset will be parsed, but the
   2121  1.1  tron <code>startDoctypeDeclHandler</code> and
   2122  1.1  tron <code>endDoctypeDeclHandler</code> functions, if set, will not be
   2123  1.1  tron called.  The setting of parameter entity parsing, controlled using
   2124  1.1  tron <code><a href= "#XML_SetParamEntityParsing"
   2125  1.1  tron >XML_SetParamEntityParsing</a></code>, will be honored.</p>
   2126  1.1  tron 
   2127  1.1  tron <p>The application-provided external subset is read by calling the
   2128  1.1  tron external entity reference handler set via <code><a href=
   2129  1.1  tron "#XML_SetExternalEntityRefHandler"
   2130  1.1  tron >XML_SetExternalEntityRefHandler</a></code> with both
   2131  1.1  tron <code>publicId</code> and <code>systemId</code> set to NULL.</p>
   2132  1.1  tron 
   2133  1.1  tron <p>If this function is called after parsing has begun, it returns
   2134  1.1  tron <code>XML_ERROR_CANT_CHANGE_FEATURE_ONCE_PARSING</code> and ignores
   2135  1.1  tron <code>useDTD</code>.  If called when Expat has been compiled without
   2136  1.1  tron DTD support, it returns
   2137  1.1  tron <code>XML_ERROR_FEATURE_REQUIRES_XML_DTD</code>.  Otherwise, it
   2138  1.1  tron returns <code>XML_ERROR_NONE</code>.</p>
   2139  1.1  tron 
   2140  1.1  tron <p><b>Note:</b> For the purpose of checking WFC: Entity Declared, passing
   2141  1.1  tron <code>useDTD == XML_TRUE</code> will make the parser behave as if
   2142  1.1  tron the document had a DTD with an external subset. This holds true even if
   2143  1.1  tron the external entity reference handler returns without action.</p>
   2144  1.1  tron </div>
   2145  1.1  tron 
   2146  1.1  tron <pre class="fcndec" id="XML_SetReturnNSTriplet">
   2147  1.1  tron void XMLCALL
   2148  1.1  tron XML_SetReturnNSTriplet(XML_Parser parser,
   2149  1.1  tron                        int        do_nst);
   2150  1.1  tron </pre>
   2151  1.1  tron <div class="fcndef">
   2152  1.1  tron <p>
   2153  1.1  tron This function only has an effect when using a parser created with
   2154  1.1  tron <code><a href= "#XML_ParserCreateNS" >XML_ParserCreateNS</a></code>,
   2155  1.1  tron i.e. when namespace processing is in effect. The <code>do_nst</code>
   2156  1.1  tron sets whether or not prefixes are returned with names qualified with a
   2157  1.1  tron namespace prefix. If this function is called with <code>do_nst</code>
   2158  1.1  tron non-zero, then afterwards namespace qualified names (that is qualified
   2159  1.1  tron with a prefix as opposed to belonging to a default namespace) are
   2160  1.1  tron returned as a triplet with the three parts separated by the namespace
   2161  1.1  tron separator specified when the parser was created.  The order of
   2162  1.1  tron returned parts is URI, local name, and prefix.</p> <p>If
   2163  1.1  tron <code>do_nst</code> is zero, then namespaces are reported in the
   2164  1.1  tron default manner, URI then local_name separated by the namespace
   2165  1.1  tron separator.</p>
   2166  1.1  tron </div>
   2167  1.1  tron 
   2168  1.1  tron <pre class="fcndec" id="XML_DefaultCurrent">
   2169  1.1  tron void XMLCALL
   2170  1.1  tron XML_DefaultCurrent(XML_Parser parser);
   2171  1.1  tron </pre>
   2172  1.1  tron <div class="fcndef">
   2173  1.1  tron This can be called within a handler for a start element, end element,
   2174  1.1  tron processing instruction or character data.  It causes the corresponding
   2175  1.1  tron markup to be passed to the default handler set by <code><a
   2176  1.1  tron href="#XML_SetDefaultHandler" >XML_SetDefaultHandler</a></code> or
   2177  1.1  tron <code><a href="#XML_SetDefaultHandlerExpand"
   2178  1.1  tron >XML_SetDefaultHandlerExpand</a></code>.  It does nothing if there is
   2179  1.1  tron not a default handler.
   2180  1.1  tron </div>
   2181  1.1  tron 
   2182  1.1  tron <pre class="fcndec" id="XML_ExpatVersion">
   2183  1.1  tron XML_LChar * XMLCALL
   2184  1.1  tron XML_ExpatVersion();
   2185  1.1  tron </pre>
   2186  1.1  tron <div class="fcndef">
   2187  1.1  tron Return the library version as a string (e.g. <code>"expat_1.95.1"</code>).
   2188  1.1  tron </div>
   2189  1.1  tron 
   2190  1.1  tron <pre class="fcndec" id="XML_ExpatVersionInfo">
   2191  1.1  tron struct XML_Expat_Version XMLCALL
   2192  1.1  tron XML_ExpatVersionInfo();
   2193  1.1  tron </pre>
   2194  1.1  tron <pre class="signature">
   2195  1.1  tron typedef struct {
   2196  1.1  tron   int major;
   2197  1.1  tron   int minor;
   2198  1.1  tron   int micro;
   2199  1.1  tron } XML_Expat_Version;
   2200  1.1  tron </pre>
   2201  1.1  tron <div class="fcndef">
   2202  1.1  tron Return the library version information as a structure.
   2203  1.1  tron Some macros are also defined that support compile-time tests of the
   2204  1.1  tron library version:
   2205  1.1  tron <ul>
   2206  1.1  tron <li><code>XML_MAJOR_VERSION</code></li>
   2207  1.1  tron <li><code>XML_MINOR_VERSION</code></li>
   2208  1.1  tron <li><code>XML_MICRO_VERSION</code></li>
   2209  1.1  tron </ul>
   2210  1.1  tron Testing these constants is currently the best way to determine if
   2211  1.1  tron particular parts of the Expat API are available.
   2212  1.1  tron </div>
   2213  1.1  tron 
   2214  1.1  tron <pre class="fcndec" id="XML_GetFeatureList">
   2215  1.1  tron const XML_Feature * XMLCALL
   2216  1.1  tron XML_GetFeatureList();
   2217  1.1  tron </pre>
   2218  1.1  tron <pre class="signature">
   2219  1.1  tron enum XML_FeatureEnum {
   2220  1.1  tron   XML_FEATURE_END = 0,
   2221  1.1  tron   XML_FEATURE_UNICODE,
   2222  1.1  tron   XML_FEATURE_UNICODE_WCHAR_T,
   2223  1.1  tron   XML_FEATURE_DTD,
   2224  1.1  tron   XML_FEATURE_CONTEXT_BYTES,
   2225  1.1  tron   XML_FEATURE_MIN_SIZE,
   2226  1.1  tron   XML_FEATURE_SIZEOF_XML_CHAR,
   2227  1.1  tron   XML_FEATURE_SIZEOF_XML_LCHAR,
   2228  1.1  tron   XML_FEATURE_NS,
   2229  1.1  tron   XML_FEATURE_LARGE_SIZE
   2230  1.1  tron };
   2231  1.1  tron 
   2232  1.1  tron typedef struct {
   2233  1.1  tron   enum XML_FeatureEnum  feature;
   2234  1.1  tron   XML_LChar            *name;
   2235  1.1  tron   long int              value;
   2236  1.1  tron } XML_Feature;
   2237  1.1  tron </pre>
   2238  1.1  tron <div class="fcndef">
   2239  1.1  tron <p>Returns a list of "feature" records, providing details on how
   2240  1.1  tron Expat was configured at compile time.  Most applications should not
   2241  1.1  tron need to worry about this, but this information is otherwise not
   2242  1.1  tron available from Expat.  This function allows code that does need to
   2243  1.1  tron check these features to do so at runtime.</p>
   2244  1.1  tron 
   2245  1.1  tron <p>The return value is an array of <code>XML_Feature</code>,
   2246  1.1  tron terminated by a record with a <code>feature</code> of
   2247  1.1  tron <code>XML_FEATURE_END</code> and <code>name</code> of NULL,
   2248  1.1  tron identifying the feature-test macros Expat was compiled with.  Since an
   2249  1.1  tron application that requires this kind of information needs to determine
   2250  1.1  tron the type of character the <code>name</code> points to, records for the
   2251  1.1  tron <code>XML_FEATURE_SIZEOF_XML_CHAR</code> and
   2252  1.1  tron <code>XML_FEATURE_SIZEOF_XML_LCHAR</code> will be located at the
   2253  1.1  tron beginning of the list, followed by <code>XML_FEATURE_UNICODE</code>
   2254  1.1  tron and <code>XML_FEATURE_UNICODE_WCHAR_T</code>, if they are present at
   2255  1.1  tron all.</p>
   2256  1.1  tron 
   2257  1.1  tron <p>Some features have an associated value.  If there isn't an
   2258  1.1  tron associated value, the <code>value</code> field is set to 0.  At this
   2259  1.1  tron time, the following features have been defined to have values:</p>
   2260  1.1  tron 
   2261  1.1  tron <dl>
   2262  1.1  tron   <dt><code>XML_FEATURE_SIZEOF_XML_CHAR</code></dt>
   2263  1.1  tron   <dd>The number of bytes occupied by one <code>XML_Char</code>
   2264  1.1  tron   character.</dd>
   2265  1.1  tron   <dt><code>XML_FEATURE_SIZEOF_XML_LCHAR</code></dt>
   2266  1.1  tron   <dd>The number of bytes occupied by one <code>XML_LChar</code>
   2267  1.1  tron   character.</dd>
   2268  1.1  tron   <dt><code>XML_FEATURE_CONTEXT_BYTES</code></dt>
   2269  1.1  tron   <dd>The maximum number of characters of context which can be
   2270  1.1  tron   reported by <code><a href= "#XML_GetInputContext"
   2271  1.1  tron   >XML_GetInputContext</a></code>.</dd>
   2272  1.1  tron </dl>
   2273  1.1  tron </div>
   2274  1.1  tron 
   2275  1.1  tron <pre class="fcndec" id="XML_FreeContentModel">
   2276  1.1  tron void XMLCALL
   2277  1.1  tron XML_FreeContentModel(XML_Parser parser, XML_Content *model);
   2278  1.1  tron </pre>
   2279  1.1  tron <div class="fcndef">
   2280  1.1  tron Function to deallocate the <code>model</code> argument passed to the
   2281  1.1  tron <code>XML_ElementDeclHandler</code> callback set using <code><a
   2282  1.1  tron href="#XML_SetElementDeclHandler" >XML_ElementDeclHandler</a></code>.
   2283  1.1  tron This function should not be used for any other purpose.
   2284  1.1  tron </div>
   2285  1.1  tron 
   2286  1.1  tron <p>The following functions allow external code to share the memory
   2287  1.1  tron allocator an <code>XML_Parser</code> has been configured to use.  This
   2288  1.1  tron is especially useful for third-party libraries that interact with a
   2289  1.1  tron parser object created by application code, or heavily layered
   2290  1.1  tron applications.  This can be essential when using dynamically loaded
   2291  1.1  tron libraries which use different C standard libraries (this can happen on
   2292  1.1  tron Windows, at least).</p>
   2293  1.1  tron 
   2294  1.1  tron <pre class="fcndec" id="XML_MemMalloc">
   2295  1.1  tron void * XMLCALL
   2296  1.1  tron XML_MemMalloc(XML_Parser parser, size_t size);
   2297  1.1  tron </pre>
   2298  1.1  tron <div class="fcndef">
   2299  1.1  tron Allocate <code>size</code> bytes of memory using the allocator the
   2300  1.1  tron <code>parser</code> object has been configured to use.  Returns a
   2301  1.1  tron pointer to the memory or NULL on failure.  Memory allocated in this
   2302  1.1  tron way must be freed using <code><a href="#XML_MemFree"
   2303  1.1  tron >XML_MemFree</a></code>.
   2304  1.1  tron </div>
   2305  1.1  tron 
   2306  1.1  tron <pre class="fcndec" id="XML_MemRealloc">
   2307  1.1  tron void * XMLCALL
   2308  1.1  tron XML_MemRealloc(XML_Parser parser, void *ptr, size_t size);
   2309  1.1  tron </pre>
   2310  1.1  tron <div class="fcndef">
   2311  1.1  tron Allocate <code>size</code> bytes of memory using the allocator the
   2312  1.1  tron <code>parser</code> object has been configured to use.
   2313  1.1  tron <code>ptr</code> must point to a block of memory allocated by <code><a
   2314  1.1  tron href="#XML_MemMalloc" >XML_MemMalloc</a></code> or
   2315  1.1  tron <code>XML_MemRealloc</code>, or be NULL.  This function tries to
   2316  1.1  tron expand the block pointed to by <code>ptr</code> if possible.  Returns
   2317  1.1  tron a pointer to the memory or NULL on failure.  On success, the original
   2318  1.1  tron block has either been expanded or freed.  On failure, the original
   2319  1.1  tron block has not been freed; the caller is responsible for freeing the
   2320  1.1  tron original block.  Memory allocated in this way must be freed using
   2321  1.1  tron <code><a href="#XML_MemFree"
   2322  1.1  tron >XML_MemFree</a></code>.
   2323  1.1  tron </div>
   2324  1.1  tron 
   2325  1.1  tron <pre class="fcndec" id="XML_MemFree">
   2326  1.1  tron void XMLCALL
   2327  1.1  tron XML_MemFree(XML_Parser parser, void *ptr);
   2328  1.1  tron </pre>
   2329  1.1  tron <div class="fcndef">
   2330  1.1  tron Free a block of memory pointed to by <code>ptr</code>.  The block must
   2331  1.1  tron have been allocated by <code><a href="#XML_MemMalloc"
   2332  1.1  tron >XML_MemMalloc</a></code> or <code>XML_MemRealloc</code>, or be NULL.
   2333  1.1  tron </div>
   2334  1.1  tron 
   2335  1.1  tron <hr />
   2336  1.1  tron <p><a href="http://validator.w3.org/check/referer"><img
   2337  1.1  tron         src="valid-xhtml10.png" alt="Valid XHTML 1.0!"
   2338  1.1  tron         height="31" width="88" class="noborder" /></a></p>
   2339  1.1  tron </div>
   2340  1.1  tron </body>
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