15bb6a25fSPoul-Henning Kamp<?xml version="1.0" encoding="iso-8859-1"?> 25bb6a25fSPoul-Henning Kamp<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" 35bb6a25fSPoul-Henning Kamp "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd"> 45bb6a25fSPoul-Henning Kamp<html> 55bb6a25fSPoul-Henning Kamp<head> 6cc68614dSXin LI<!-- 7cc68614dSXin LI __ __ _ 8cc68614dSXin LI ___\ \/ /_ __ __ _| |_ 9cc68614dSXin LI / _ \\ /| '_ \ / _` | __| 10cc68614dSXin LI | __// \| |_) | (_| | |_ 11cc68614dSXin LI \___/_/\_\ .__/ \__,_|\__| 12cc68614dSXin LI |_| XML parser 13cc68614dSXin LI 14cc68614dSXin LI Copyright (c) 2000 Clark Cooper <coopercc@users.sourceforge.net> 15cc68614dSXin LI Copyright (c) 2000-2004 Fred L. Drake, Jr. <fdrake@users.sourceforge.net> 16cc68614dSXin LI Copyright (c) 2002-2012 Karl Waclawek <karl@waclawek.net> 174543ef51SXin LI Copyright (c) 2017-2024 Sebastian Pipping <sebastian@pipping.org> 18cc68614dSXin LI Copyright (c) 2017 Jakub Wilk <jwilk@jwilk.net> 19cc68614dSXin LI Copyright (c) 2021 Tomas Korbar <tkorbar@redhat.com> 20cc68614dSXin LI Copyright (c) 2021 Nicolas Cavallari <nicolas.cavallari@green-communications.fr> 217ed8e142SXin LI Copyright (c) 2022 Thijs Schreijer <thijs@thijsschreijer.nl> 224543ef51SXin LI Copyright (c) 2023 Hanno Böck <hanno@gentoo.org> 234543ef51SXin LI Copyright (c) 2023 Sony Corporation / Snild Dolkow <snild@sony.com> 24cc68614dSXin LI Licensed under the MIT license: 25cc68614dSXin LI 26cc68614dSXin LI Permission is hereby granted, free of charge, to any person obtaining 27cc68614dSXin LI a copy of this software and associated documentation files (the 28cc68614dSXin LI "Software"), to deal in the Software without restriction, including 29cc68614dSXin LI without limitation the rights to use, copy, modify, merge, publish, 30cc68614dSXin LI distribute, sublicense, and/or sell copies of the Software, and to permit 31cc68614dSXin LI persons to whom the Software is furnished to do so, subject to the 32cc68614dSXin LI following conditions: 33cc68614dSXin LI 34cc68614dSXin LI The above copyright notice and this permission notice shall be included 35cc68614dSXin LI in all copies or substantial portions of the Software. 36cc68614dSXin LI 37cc68614dSXin LI THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, 38cc68614dSXin LI EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 39cc68614dSXin LI MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN 40cc68614dSXin LI NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, 41cc68614dSXin LI DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR 42cc68614dSXin LI OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE 43cc68614dSXin LI USE OR OTHER DEALINGS IN THE SOFTWARE. 44cc68614dSXin LI--> 455bb6a25fSPoul-Henning Kamp <title>Expat XML Parser</title> 465bb6a25fSPoul-Henning Kamp <meta name="author" content="Clark Cooper, coopercc@netheaven.com" /> 475bb6a25fSPoul-Henning Kamp <meta http-equiv="Content-Style-Type" content="text/css" /> 48cc68614dSXin LI <link href="ok.min.css" rel="stylesheet" type="text/css" /> 495bb6a25fSPoul-Henning Kamp <link href="style.css" rel="stylesheet" type="text/css" /> 505bb6a25fSPoul-Henning Kamp</head> 515bb6a25fSPoul-Henning Kamp<body> 52cc68614dSXin LI <div> 53cc68614dSXin LI <h1> 54cc68614dSXin LI The Expat XML Parser 55*908f215eSXin LI <small>Release 2.6.4</small> 56cc68614dSXin LI </h1> 57cc68614dSXin LI </div> 58220ed979SColeman Kane<div class="content"> 595bb6a25fSPoul-Henning Kamp 605bb6a25fSPoul-Henning Kamp<p>Expat is a library, written in C, for parsing XML documents. It's 615bb6a25fSPoul-Henning Kampthe underlying XML parser for the open source Mozilla project, Perl's 625bb6a25fSPoul-Henning Kamp<code>XML::Parser</code>, Python's <code>xml.parsers.expat</code>, and 635bb6a25fSPoul-Henning Kampother open-source XML parsers.</p> 645bb6a25fSPoul-Henning Kamp 655bb6a25fSPoul-Henning Kamp<p>This library is the creation of James Clark, who's also given us 660a48773fSEric van Gyzengroff (an nroff look-alike), Jade (an implementation of ISO's DSSSL 675bb6a25fSPoul-Henning Kampstylesheet language for SGML), XP (a Java XML parser package), XT (a 685bb6a25fSPoul-Henning KampJava XSL engine). James was also the technical lead on the XML 695bb6a25fSPoul-Henning KampWorking Group at W3C that produced the XML specification.</p> 705bb6a25fSPoul-Henning Kamp 715bb6a25fSPoul-Henning Kamp<p>This is free software, licensed under the <a 725bb6a25fSPoul-Henning Kamphref="../COPYING">MIT/X Consortium license</a>. You may download it 734543ef51SXin LIfrom <a href="https://libexpat.github.io/">the Expat home page</a>. 745bb6a25fSPoul-Henning Kamp</p> 755bb6a25fSPoul-Henning Kamp 76220ed979SColeman Kane<p>The bulk of this document was originally commissioned as an article 774543ef51SXin LIby <a href="https://www.xml.com/">XML.com</a>. They graciously allowed 78220ed979SColeman KaneClark Cooper to retain copyright and to distribute it with Expat. 79220ed979SColeman KaneThis version has been substantially extended to include documentation 80220ed979SColeman Kaneon features which have been added since the original article was 81220ed979SColeman Kanepublished, and additional information on using the original 82220ed979SColeman Kaneinterface.</p> 835bb6a25fSPoul-Henning Kamp 845bb6a25fSPoul-Henning Kamp<hr /> 855bb6a25fSPoul-Henning Kamp<h2>Table of Contents</h2> 865bb6a25fSPoul-Henning Kamp<ul> 875bb6a25fSPoul-Henning Kamp <li><a href="#overview">Overview</a></li> 885bb6a25fSPoul-Henning Kamp <li><a href="#building">Building and Installing</a></li> 895bb6a25fSPoul-Henning Kamp <li><a href="#using">Using Expat</a></li> 905bb6a25fSPoul-Henning Kamp <li><a href="#reference">Reference</a> 915bb6a25fSPoul-Henning Kamp <ul> 925bb6a25fSPoul-Henning Kamp <li><a href="#creation">Parser Creation Functions</a> 935bb6a25fSPoul-Henning Kamp <ul> 945bb6a25fSPoul-Henning Kamp <li><a href="#XML_ParserCreate">XML_ParserCreate</a></li> 955bb6a25fSPoul-Henning Kamp <li><a href="#XML_ParserCreateNS">XML_ParserCreateNS</a></li> 965bb6a25fSPoul-Henning Kamp <li><a href="#XML_ParserCreate_MM">XML_ParserCreate_MM</a></li> 975bb6a25fSPoul-Henning Kamp <li><a href="#XML_ExternalEntityParserCreate">XML_ExternalEntityParserCreate</a></li> 985bb6a25fSPoul-Henning Kamp <li><a href="#XML_ParserFree">XML_ParserFree</a></li> 995bb6a25fSPoul-Henning Kamp <li><a href="#XML_ParserReset">XML_ParserReset</a></li> 1005bb6a25fSPoul-Henning Kamp </ul> 1015bb6a25fSPoul-Henning Kamp </li> 1025bb6a25fSPoul-Henning Kamp <li><a href="#parsing">Parsing Functions</a> 1035bb6a25fSPoul-Henning Kamp <ul> 1045bb6a25fSPoul-Henning Kamp <li><a href="#XML_Parse">XML_Parse</a></li> 1055bb6a25fSPoul-Henning Kamp <li><a href="#XML_ParseBuffer">XML_ParseBuffer</a></li> 1065bb6a25fSPoul-Henning Kamp <li><a href="#XML_GetBuffer">XML_GetBuffer</a></li> 107220ed979SColeman Kane <li><a href="#XML_StopParser">XML_StopParser</a></li> 108220ed979SColeman Kane <li><a href="#XML_ResumeParser">XML_ResumeParser</a></li> 109220ed979SColeman Kane <li><a href="#XML_GetParsingStatus">XML_GetParsingStatus</a></li> 1105bb6a25fSPoul-Henning Kamp </ul> 1115bb6a25fSPoul-Henning Kamp </li> 1125bb6a25fSPoul-Henning Kamp <li><a href="#setting">Handler Setting Functions</a> 1135bb6a25fSPoul-Henning Kamp <ul> 1145bb6a25fSPoul-Henning Kamp <li><a href="#XML_SetStartElementHandler">XML_SetStartElementHandler</a></li> 1155bb6a25fSPoul-Henning Kamp <li><a href="#XML_SetEndElementHandler">XML_SetEndElementHandler</a></li> 1165bb6a25fSPoul-Henning Kamp <li><a href="#XML_SetElementHandler">XML_SetElementHandler</a></li> 1175bb6a25fSPoul-Henning Kamp <li><a href="#XML_SetCharacterDataHandler">XML_SetCharacterDataHandler</a></li> 1185bb6a25fSPoul-Henning Kamp <li><a href="#XML_SetProcessingInstructionHandler">XML_SetProcessingInstructionHandler</a></li> 1195bb6a25fSPoul-Henning Kamp <li><a href="#XML_SetCommentHandler">XML_SetCommentHandler</a></li> 1205bb6a25fSPoul-Henning Kamp <li><a href="#XML_SetStartCdataSectionHandler">XML_SetStartCdataSectionHandler</a></li> 1215bb6a25fSPoul-Henning Kamp <li><a href="#XML_SetEndCdataSectionHandler">XML_SetEndCdataSectionHandler</a></li> 1225bb6a25fSPoul-Henning Kamp <li><a href="#XML_SetCdataSectionHandler">XML_SetCdataSectionHandler</a></li> 1235bb6a25fSPoul-Henning Kamp <li><a href="#XML_SetDefaultHandler">XML_SetDefaultHandler</a></li> 1245bb6a25fSPoul-Henning Kamp <li><a href="#XML_SetDefaultHandlerExpand">XML_SetDefaultHandlerExpand</a></li> 1255bb6a25fSPoul-Henning Kamp <li><a href="#XML_SetExternalEntityRefHandler">XML_SetExternalEntityRefHandler</a></li> 126220ed979SColeman Kane <li><a href="#XML_SetExternalEntityRefHandlerArg">XML_SetExternalEntityRefHandlerArg</a></li> 1275bb6a25fSPoul-Henning Kamp <li><a href="#XML_SetSkippedEntityHandler">XML_SetSkippedEntityHandler</a></li> 1285bb6a25fSPoul-Henning Kamp <li><a href="#XML_SetUnknownEncodingHandler">XML_SetUnknownEncodingHandler</a></li> 1295bb6a25fSPoul-Henning Kamp <li><a href="#XML_SetStartNamespaceDeclHandler">XML_SetStartNamespaceDeclHandler</a></li> 1305bb6a25fSPoul-Henning Kamp <li><a href="#XML_SetEndNamespaceDeclHandler">XML_SetEndNamespaceDeclHandler</a></li> 1315bb6a25fSPoul-Henning Kamp <li><a href="#XML_SetNamespaceDeclHandler">XML_SetNamespaceDeclHandler</a></li> 1325bb6a25fSPoul-Henning Kamp <li><a href="#XML_SetXmlDeclHandler">XML_SetXmlDeclHandler</a></li> 1335bb6a25fSPoul-Henning Kamp <li><a href="#XML_SetStartDoctypeDeclHandler">XML_SetStartDoctypeDeclHandler</a></li> 1345bb6a25fSPoul-Henning Kamp <li><a href="#XML_SetEndDoctypeDeclHandler">XML_SetEndDoctypeDeclHandler</a></li> 1355bb6a25fSPoul-Henning Kamp <li><a href="#XML_SetDoctypeDeclHandler">XML_SetDoctypeDeclHandler</a></li> 1365bb6a25fSPoul-Henning Kamp <li><a href="#XML_SetElementDeclHandler">XML_SetElementDeclHandler</a></li> 1375bb6a25fSPoul-Henning Kamp <li><a href="#XML_SetAttlistDeclHandler">XML_SetAttlistDeclHandler</a></li> 1385bb6a25fSPoul-Henning Kamp <li><a href="#XML_SetEntityDeclHandler">XML_SetEntityDeclHandler</a></li> 1395bb6a25fSPoul-Henning Kamp <li><a href="#XML_SetUnparsedEntityDeclHandler">XML_SetUnparsedEntityDeclHandler</a></li> 1405bb6a25fSPoul-Henning Kamp <li><a href="#XML_SetNotationDeclHandler">XML_SetNotationDeclHandler</a></li> 1415bb6a25fSPoul-Henning Kamp <li><a href="#XML_SetNotStandaloneHandler">XML_SetNotStandaloneHandler</a></li> 1425bb6a25fSPoul-Henning Kamp </ul> 1435bb6a25fSPoul-Henning Kamp </li> 1445bb6a25fSPoul-Henning Kamp <li><a href="#position">Parse Position and Error Reporting Functions</a> 1455bb6a25fSPoul-Henning Kamp <ul> 1465bb6a25fSPoul-Henning Kamp <li><a href="#XML_GetErrorCode">XML_GetErrorCode</a></li> 1475bb6a25fSPoul-Henning Kamp <li><a href="#XML_ErrorString">XML_ErrorString</a></li> 1485bb6a25fSPoul-Henning Kamp <li><a href="#XML_GetCurrentByteIndex">XML_GetCurrentByteIndex</a></li> 1495bb6a25fSPoul-Henning Kamp <li><a href="#XML_GetCurrentLineNumber">XML_GetCurrentLineNumber</a></li> 1505bb6a25fSPoul-Henning Kamp <li><a href="#XML_GetCurrentColumnNumber">XML_GetCurrentColumnNumber</a></li> 1515bb6a25fSPoul-Henning Kamp <li><a href="#XML_GetCurrentByteCount">XML_GetCurrentByteCount</a></li> 1525bb6a25fSPoul-Henning Kamp <li><a href="#XML_GetInputContext">XML_GetInputContext</a></li> 1535bb6a25fSPoul-Henning Kamp </ul> 1545bb6a25fSPoul-Henning Kamp </li> 155cc68614dSXin LI <li> 1564543ef51SXin LI <a href="#attack-protection">Attack Protection</a> 157cc68614dSXin LI <ul> 158cc68614dSXin LI <li><a href="#XML_SetBillionLaughsAttackProtectionMaximumAmplification">XML_SetBillionLaughsAttackProtectionMaximumAmplification</a></li> 159cc68614dSXin LI <li><a href="#XML_SetBillionLaughsAttackProtectionActivationThreshold">XML_SetBillionLaughsAttackProtectionActivationThreshold</a></li> 1604543ef51SXin LI <li><a href="#XML_SetReparseDeferralEnabled">XML_SetReparseDeferralEnabled</a></li> 161cc68614dSXin LI </ul> 162cc68614dSXin LI </li> 1635bb6a25fSPoul-Henning Kamp <li><a href="#miscellaneous">Miscellaneous Functions</a> 1645bb6a25fSPoul-Henning Kamp <ul> 1655bb6a25fSPoul-Henning Kamp <li><a href="#XML_SetUserData">XML_SetUserData</a></li> 1665bb6a25fSPoul-Henning Kamp <li><a href="#XML_GetUserData">XML_GetUserData</a></li> 1675bb6a25fSPoul-Henning Kamp <li><a href="#XML_UseParserAsHandlerArg">XML_UseParserAsHandlerArg</a></li> 1685bb6a25fSPoul-Henning Kamp <li><a href="#XML_SetBase">XML_SetBase</a></li> 1695bb6a25fSPoul-Henning Kamp <li><a href="#XML_GetBase">XML_GetBase</a></li> 1705bb6a25fSPoul-Henning Kamp <li><a href="#XML_GetSpecifiedAttributeCount">XML_GetSpecifiedAttributeCount</a></li> 1715bb6a25fSPoul-Henning Kamp <li><a href="#XML_GetIdAttributeIndex">XML_GetIdAttributeIndex</a></li> 172e3466a89SXin LI <li><a href="#XML_GetAttributeInfo">XML_GetAttributeInfo</a></li> 1735bb6a25fSPoul-Henning Kamp <li><a href="#XML_SetEncoding">XML_SetEncoding</a></li> 1745bb6a25fSPoul-Henning Kamp <li><a href="#XML_SetParamEntityParsing">XML_SetParamEntityParsing</a></li> 175e3466a89SXin LI <li><a href="#XML_SetHashSalt">XML_SetHashSalt</a></li> 1765bb6a25fSPoul-Henning Kamp <li><a href="#XML_UseForeignDTD">XML_UseForeignDTD</a></li> 1775bb6a25fSPoul-Henning Kamp <li><a href="#XML_SetReturnNSTriplet">XML_SetReturnNSTriplet</a></li> 1785bb6a25fSPoul-Henning Kamp <li><a href="#XML_DefaultCurrent">XML_DefaultCurrent</a></li> 1795bb6a25fSPoul-Henning Kamp <li><a href="#XML_ExpatVersion">XML_ExpatVersion</a></li> 1805bb6a25fSPoul-Henning Kamp <li><a href="#XML_ExpatVersionInfo">XML_ExpatVersionInfo</a></li> 1815bb6a25fSPoul-Henning Kamp <li><a href="#XML_GetFeatureList">XML_GetFeatureList</a></li> 182220ed979SColeman Kane <li><a href="#XML_FreeContentModel">XML_FreeContentModel</a></li> 183220ed979SColeman Kane <li><a href="#XML_MemMalloc">XML_MemMalloc</a></li> 184220ed979SColeman Kane <li><a href="#XML_MemRealloc">XML_MemRealloc</a></li> 185220ed979SColeman Kane <li><a href="#XML_MemFree">XML_MemFree</a></li> 1865bb6a25fSPoul-Henning Kamp </ul> 1875bb6a25fSPoul-Henning Kamp </li> 1885bb6a25fSPoul-Henning Kamp </ul> 1895bb6a25fSPoul-Henning Kamp </li> 1905bb6a25fSPoul-Henning Kamp</ul> 1915bb6a25fSPoul-Henning Kamp 1925bb6a25fSPoul-Henning Kamp<hr /> 1935bb6a25fSPoul-Henning Kamp<h2><a name="overview">Overview</a></h2> 1945bb6a25fSPoul-Henning Kamp 1955bb6a25fSPoul-Henning Kamp<p>Expat is a stream-oriented parser. You register callback (or 1965bb6a25fSPoul-Henning Kamphandler) functions with the parser and then start feeding it the 1975bb6a25fSPoul-Henning Kampdocument. As the parser recognizes parts of the document, it will 1985bb6a25fSPoul-Henning Kampcall the appropriate handler for that part (if you've registered one.) 1995bb6a25fSPoul-Henning KampThe document is fed to the parser in pieces, so you can start parsing 2005bb6a25fSPoul-Henning Kampbefore you have all the document. This also allows you to parse really 2015bb6a25fSPoul-Henning Kamphuge documents that won't fit into memory.</p> 2025bb6a25fSPoul-Henning Kamp 2035bb6a25fSPoul-Henning Kamp<p>Expat can be intimidating due to the many kinds of handlers and 2045bb6a25fSPoul-Henning Kampoptions you can set. But you only need to learn four functions in 2055bb6a25fSPoul-Henning Kamporder to do 90% of what you'll want to do with it:</p> 2065bb6a25fSPoul-Henning Kamp 2075bb6a25fSPoul-Henning Kamp<dl> 2085bb6a25fSPoul-Henning Kamp 2095bb6a25fSPoul-Henning Kamp<dt><code><a href= "#XML_ParserCreate" 2105bb6a25fSPoul-Henning Kamp >XML_ParserCreate</a></code></dt> 2115bb6a25fSPoul-Henning Kamp <dd>Create a new parser object.</dd> 2125bb6a25fSPoul-Henning Kamp 2135bb6a25fSPoul-Henning Kamp<dt><code><a href= "#XML_SetElementHandler" 2145bb6a25fSPoul-Henning Kamp >XML_SetElementHandler</a></code></dt> 2155bb6a25fSPoul-Henning Kamp <dd>Set handlers for start and end tags.</dd> 2165bb6a25fSPoul-Henning Kamp 2175bb6a25fSPoul-Henning Kamp<dt><code><a href= "#XML_SetCharacterDataHandler" 2185bb6a25fSPoul-Henning Kamp >XML_SetCharacterDataHandler</a></code></dt> 2195bb6a25fSPoul-Henning Kamp <dd>Set handler for text.</dd> 2205bb6a25fSPoul-Henning Kamp 2215bb6a25fSPoul-Henning Kamp<dt><code><a href= "#XML_Parse" 2225bb6a25fSPoul-Henning Kamp >XML_Parse</a></code></dt> 2235bb6a25fSPoul-Henning Kamp <dd>Pass a buffer full of document to the parser</dd> 2245bb6a25fSPoul-Henning Kamp</dl> 2255bb6a25fSPoul-Henning Kamp 2265bb6a25fSPoul-Henning Kamp<p>These functions and others are described in the <a 2275bb6a25fSPoul-Henning Kamphref="#reference">reference</a> part of this document. The reference 2285bb6a25fSPoul-Henning Kampsection also describes in detail the parameters passed to the 2295bb6a25fSPoul-Henning Kampdifferent types of handlers.</p> 2305bb6a25fSPoul-Henning Kamp 2315bb6a25fSPoul-Henning Kamp<p>Let's look at a very simple example program that only uses 3 of the 2325bb6a25fSPoul-Henning Kampabove functions (it doesn't need to set a character handler.) The 2335bb6a25fSPoul-Henning Kampprogram <a href="../examples/outline.c">outline.c</a> prints an 2345bb6a25fSPoul-Henning Kampelement outline, indenting child elements to distinguish them from the 2355bb6a25fSPoul-Henning Kampparent element that contains them. The start handler does all the 2365bb6a25fSPoul-Henning Kampwork. It prints two indenting spaces for every level of ancestor 2375bb6a25fSPoul-Henning Kampelements, then it prints the element and attribute 2385bb6a25fSPoul-Henning Kampinformation. Finally it increments the global <code>Depth</code> 2395bb6a25fSPoul-Henning Kampvariable.</p> 2405bb6a25fSPoul-Henning Kamp 2415bb6a25fSPoul-Henning Kamp<pre class="eg"> 2425bb6a25fSPoul-Henning Kampint Depth; 2435bb6a25fSPoul-Henning Kamp 244220ed979SColeman Kanevoid XMLCALL 2455bb6a25fSPoul-Henning Kampstart(void *data, const char *el, const char **attr) { 2465bb6a25fSPoul-Henning Kamp int i; 2475bb6a25fSPoul-Henning Kamp 2485bb6a25fSPoul-Henning Kamp for (i = 0; i < Depth; i++) 2495bb6a25fSPoul-Henning Kamp printf(" "); 2505bb6a25fSPoul-Henning Kamp 2515bb6a25fSPoul-Henning Kamp printf("%s", el); 2525bb6a25fSPoul-Henning Kamp 2535bb6a25fSPoul-Henning Kamp for (i = 0; attr[i]; i += 2) { 2545bb6a25fSPoul-Henning Kamp printf(" %s='%s'", attr[i], attr[i + 1]); 2555bb6a25fSPoul-Henning Kamp } 2565bb6a25fSPoul-Henning Kamp 2575bb6a25fSPoul-Henning Kamp printf("\n"); 2585bb6a25fSPoul-Henning Kamp Depth++; 2595bb6a25fSPoul-Henning Kamp} /* End of start handler */ 2605bb6a25fSPoul-Henning Kamp</pre> 2615bb6a25fSPoul-Henning Kamp 2625bb6a25fSPoul-Henning Kamp<p>The end tag simply does the bookkeeping work of decrementing 2635bb6a25fSPoul-Henning Kamp<code>Depth</code>.</p> 2645bb6a25fSPoul-Henning Kamp<pre class="eg"> 265220ed979SColeman Kanevoid XMLCALL 2665bb6a25fSPoul-Henning Kampend(void *data, const char *el) { 2675bb6a25fSPoul-Henning Kamp Depth--; 2685bb6a25fSPoul-Henning Kamp} /* End of end handler */ 2695bb6a25fSPoul-Henning Kamp</pre> 2705bb6a25fSPoul-Henning Kamp 271220ed979SColeman Kane<p>Note the <code>XMLCALL</code> annotation used for the callbacks. 272220ed979SColeman KaneThis is used to ensure that the Expat and the callbacks are using the 273220ed979SColeman Kanesame calling convention in case the compiler options used for Expat 274220ed979SColeman Kaneitself and the client code are different. Expat tries not to care 275220ed979SColeman Kanewhat the default calling convention is, though it may require that it 276220ed979SColeman Kanebe compiled with a default convention of "cdecl" on some platforms. 277220ed979SColeman KaneFor code which uses Expat, however, the calling convention is 278220ed979SColeman Kanespecified by the <code>XMLCALL</code> annotation on most platforms; 279220ed979SColeman Kanecallbacks should be defined using this annotation.</p> 280220ed979SColeman Kane 281220ed979SColeman Kane<p>The <code>XMLCALL</code> annotation was added in Expat 1.95.7, but 282220ed979SColeman Kaneexisting working Expat applications don't need to add it (since they 283220ed979SColeman Kaneare already using the "cdecl" calling convention, or they wouldn't be 284220ed979SColeman Kaneworking). The annotation is only needed if the default calling 285220ed979SColeman Kaneconvention may be something other than "cdecl". To use the annotation 286220ed979SColeman Kanesafely with older versions of Expat, you can conditionally define it 287220ed979SColeman Kane<em>after</em> including Expat's header file:</p> 288220ed979SColeman Kane 289220ed979SColeman Kane<pre class="eg"> 290220ed979SColeman Kane#include <expat.h> 291220ed979SColeman Kane 292220ed979SColeman Kane#ifndef XMLCALL 293220ed979SColeman Kane#if defined(_MSC_EXTENSIONS) && !defined(__BEOS__) && !defined(__CYGWIN__) 294220ed979SColeman Kane#define XMLCALL __cdecl 295220ed979SColeman Kane#elif defined(__GNUC__) 296220ed979SColeman Kane#define XMLCALL __attribute__((cdecl)) 297220ed979SColeman Kane#else 298220ed979SColeman Kane#define XMLCALL 299220ed979SColeman Kane#endif 300220ed979SColeman Kane#endif 301220ed979SColeman Kane</pre> 302220ed979SColeman Kane 3035bb6a25fSPoul-Henning Kamp<p>After creating the parser, the main program just has the job of 3045bb6a25fSPoul-Henning Kampshoveling the document to the parser so that it can do its work.</p> 3055bb6a25fSPoul-Henning Kamp 3065bb6a25fSPoul-Henning Kamp<hr /> 3075bb6a25fSPoul-Henning Kamp<h2><a name="building">Building and Installing Expat</a></h2> 3085bb6a25fSPoul-Henning Kamp 3095bb6a25fSPoul-Henning Kamp<p>The Expat distribution comes as a compressed (with GNU gzip) tar 3105bb6a25fSPoul-Henning Kampfile. You may download the latest version from <a href= 3114543ef51SXin LI"https://sourceforge.net/projects/expat/" >Source Forge</a>. After 3125bb6a25fSPoul-Henning Kampunpacking this, cd into the directory. Then follow either the Win32 3135bb6a25fSPoul-Henning Kampdirections or Unix directions below.</p> 3145bb6a25fSPoul-Henning Kamp 3155bb6a25fSPoul-Henning Kamp<h3>Building under Win32</h3> 3165bb6a25fSPoul-Henning Kamp 3175bb6a25fSPoul-Henning Kamp<p>If you're using the GNU compiler under cygwin, follow the Unix 3185bb6a25fSPoul-Henning Kampdirections in the next section. Otherwise if you have Microsoft's 3196b2c1e49SXin LIDeveloper Studio installed, 3206b2c1e49SXin LIyou can use CMake to generate a <code>.sln</code> file, e.g. 3216b2c1e49SXin LI<code> 322ffd294a1SEnji Coopercmake -G"Visual Studio 16 2019" -DCMAKE_BUILD_TYPE=RelWithDebInfo . 3236b2c1e49SXin LI</code>, and build Expat using <code>msbuild /m expat.sln</code> after.</p> 3245bb6a25fSPoul-Henning Kamp 3255bb6a25fSPoul-Henning Kamp<p>Alternatively, you may download the Win32 binary package that 3265bb6a25fSPoul-Henning Kampcontains the "expat.h" include file and a pre-built DLL.</p> 3275bb6a25fSPoul-Henning Kamp 3285bb6a25fSPoul-Henning Kamp<h3>Building under Unix (or GNU)</h3> 3295bb6a25fSPoul-Henning Kamp 3305bb6a25fSPoul-Henning Kamp<p>First you'll need to run the configure shell script in order to 3315bb6a25fSPoul-Henning Kampconfigure the Makefiles and headers for your system.</p> 3325bb6a25fSPoul-Henning Kamp 3335bb6a25fSPoul-Henning Kamp<p>If you're happy with all the defaults that configure picks for you, 3345bb6a25fSPoul-Henning Kampand you have permission on your system to install into /usr/local, you 3355bb6a25fSPoul-Henning Kampcan install Expat with this sequence of commands:</p> 3365bb6a25fSPoul-Henning Kamp 3375bb6a25fSPoul-Henning Kamp<pre class="eg"> 3385bb6a25fSPoul-Henning Kamp./configure 3395bb6a25fSPoul-Henning Kampmake 3405bb6a25fSPoul-Henning Kampmake install 3415bb6a25fSPoul-Henning Kamp</pre> 3425bb6a25fSPoul-Henning Kamp 3435bb6a25fSPoul-Henning Kamp<p>There are some options that you can provide to this script, but the 3445bb6a25fSPoul-Henning Kamponly one we'll mention here is the <code>--prefix</code> option. You 3455bb6a25fSPoul-Henning Kampcan find out all the options available by running configure with just 3465bb6a25fSPoul-Henning Kampthe <code>--help</code> option.</p> 3475bb6a25fSPoul-Henning Kamp 3485bb6a25fSPoul-Henning Kamp<p>By default, the configure script sets things up so that the library 3495bb6a25fSPoul-Henning Kampgets installed in <code>/usr/local/lib</code> and the associated 3505bb6a25fSPoul-Henning Kampheader file in <code>/usr/local/include</code>. But if you were to 3515bb6a25fSPoul-Henning Kampgive the option, <code>--prefix=/home/me/mystuff</code>, then the 3525bb6a25fSPoul-Henning Kamplibrary and header would get installed in 3535bb6a25fSPoul-Henning Kamp<code>/home/me/mystuff/lib</code> and 3545bb6a25fSPoul-Henning Kamp<code>/home/me/mystuff/include</code> respectively.</p> 3555bb6a25fSPoul-Henning Kamp 356220ed979SColeman Kane<h3>Configuring Expat Using the Pre-Processor</h3> 357220ed979SColeman Kane 358220ed979SColeman Kane<p>Expat's feature set can be configured using a small number of 359ffd294a1SEnji Cooperpre-processor definitions. The symbols are:</p> 360220ed979SColeman Kane 361220ed979SColeman Kane<dl class="cpp-symbols"> 3624543ef51SXin LI<dt><a name="XML_GE">XML_GE</a></dt> 3634543ef51SXin LI<dd> 3644543ef51SXin LIAdded in Expat 2.6.0. 3654543ef51SXin LIInclude support for 3664543ef51SXin LI<a href="https://www.w3.org/TR/2006/REC-xml-20060816/#sec-physical-struct">general entities</a> 3674543ef51SXin LI(syntax <code>&e1;</code> to reference and 3684543ef51SXin LIsyntax <code><!ENTITY e1 'value1'></code> (an internal general entity) or 3694543ef51SXin LI<code><!ENTITY e2 SYSTEM 'file2'></code> (an external general entity) to declare). 3704543ef51SXin LIWith <code>XML_GE</code> enabled, general entities will be replaced by their declared replacement text; 3714543ef51SXin LIfor this to work for <em>external</em> general entities, in addition an 3724543ef51SXin LI<code><a href="#XML_SetExternalEntityRefHandler">XML_ExternalEntityRefHandler</a></code> must be set using 3734543ef51SXin LI<code><a href="#XML_SetExternalEntityRefHandler">XML_SetExternalEntityRefHandler</a></code>. 3744543ef51SXin LIAlso, enabling <code>XML_GE</code> makes 3754543ef51SXin LIthe functions <code><a href="#XML_SetBillionLaughsAttackProtectionMaximumAmplification"> 3764543ef51SXin LIXML_SetBillionLaughsAttackProtectionMaximumAmplification</a></code> and <code> 3774543ef51SXin LI<a href="#XML_SetBillionLaughsAttackProtectionActivationThreshold"> 3784543ef51SXin LIXML_SetBillionLaughsAttackProtectionActivationThreshold</a></code> available. 3794543ef51SXin LI<br/> 3804543ef51SXin LIWith <code>XML_GE</code> disabled, Expat has a smaller memory footprint and can be faster, but will 3814543ef51SXin LInot load external general entities and will replace all general entities 3824543ef51SXin LI(except the <a href="https://www.w3.org/TR/2006/REC-xml-20060816/#sec-predefined-ent">predefined five</a>: 3834543ef51SXin LI<code>amp</code>, <code>apos</code>, <code>gt</code>, <code>lt</code>, <code>quot</code>) 3844543ef51SXin LIwith a self-reference: 3854543ef51SXin LIfor example, referencing an entity <code>e1</code> via <code>&e1;</code> will be replaced 3864543ef51SXin LIby text <code>&e1;</code>. 3874543ef51SXin LI</dd> 3884543ef51SXin LI 3894543ef51SXin LI<dt><a name="XML_DTD">XML_DTD</a></dt> 390220ed979SColeman Kane<dd>Include support for using and reporting DTD-based content. If 391220ed979SColeman Kanethis is defined, default attribute values from an external DTD subset 392220ed979SColeman Kaneare reported and attribute value normalization occurs based on the 393220ed979SColeman Kanetype of attributes defined in the external subset. Without 394220ed979SColeman Kanethis, Expat has a smaller memory footprint and can be faster, but will 3954543ef51SXin LInot load external parameter entities or process conditional sections. If defined, makes 39671f0c44aSXin LIthe functions <code><a 39771f0c44aSXin LIhref="#XML_SetBillionLaughsAttackProtectionMaximumAmplification"> 39871f0c44aSXin LIXML_SetBillionLaughsAttackProtectionMaximumAmplification</a></code> and <code> 39971f0c44aSXin LI<a href="#XML_SetBillionLaughsAttackProtectionActivationThreshold"> 40071f0c44aSXin LIXML_SetBillionLaughsAttackProtectionActivationThreshold</a></code> available.</dd> 401220ed979SColeman Kane 4024543ef51SXin LI<dt><a name="XML_NS">XML_NS</a></dt> 403220ed979SColeman Kane<dd>When defined, support for the <cite><a href= 4044543ef51SXin LI"https://www.w3.org/TR/REC-xml-names/" >Namespaces in XML</a></cite> 405220ed979SColeman Kanespecification is included.</dd> 406220ed979SColeman Kane 4074543ef51SXin LI<dt><a name="XML_UNICODE">XML_UNICODE</a></dt> 408220ed979SColeman Kane<dd>When defined, character data reported to the application is 409220ed979SColeman Kaneencoded in UTF-16 using wide characters of the type 410220ed979SColeman Kane<code>XML_Char</code>. This is implied if 411220ed979SColeman Kane<code>XML_UNICODE_WCHAR_T</code> is defined.</dd> 412220ed979SColeman Kane 4134543ef51SXin LI<dt><a name="XML_UNICODE_WCHAR_T">XML_UNICODE_WCHAR_T</a></dt> 414220ed979SColeman Kane<dd>If defined, causes the <code>XML_Char</code> character type to be 415220ed979SColeman Kanedefined using the <code>wchar_t</code> type; otherwise, <code>unsigned 416220ed979SColeman Kaneshort</code> is used. Defining this implies 417220ed979SColeman Kane<code>XML_UNICODE</code>.</dd> 418220ed979SColeman Kane 4194543ef51SXin LI<dt><a name="XML_LARGE_SIZE">XML_LARGE_SIZE</a></dt> 420220ed979SColeman Kane<dd>If defined, causes the <code>XML_Size</code> and <code>XML_Index</code> 421220ed979SColeman Kaneinteger types to be at least 64 bits in size. This is intended to support 422220ed979SColeman Kaneprocessing of very large input streams, where the return values of 423220ed979SColeman Kane<code><a href="#XML_GetCurrentByteIndex" >XML_GetCurrentByteIndex</a></code>, 424220ed979SColeman Kane<code><a href="#XML_GetCurrentLineNumber" >XML_GetCurrentLineNumber</a></code> and 425220ed979SColeman Kane<code><a href="#XML_GetCurrentColumnNumber" >XML_GetCurrentColumnNumber</a></code> 426220ed979SColeman Kanecould overflow. It may not be supported by all compilers, and is turned 427220ed979SColeman Kaneoff by default.</dd> 428220ed979SColeman Kane 4294543ef51SXin LI<dt><a name="XML_CONTEXT_BYTES">XML_CONTEXT_BYTES</a></dt> 430220ed979SColeman Kane<dd>The number of input bytes of markup context which the parser will 431220ed979SColeman Kaneensure are available for reporting via <code><a href= 432220ed979SColeman Kane"#XML_GetInputContext" >XML_GetInputContext</a></code>. This is 4334543ef51SXin LInormally set to 1024, and must be set to a positive integer to enable. 4344543ef51SXin LIIf this is set to zero, the input context will not be available and <code><a 435220ed979SColeman Kanehref= "#XML_GetInputContext" >XML_GetInputContext</a></code> will 4364543ef51SXin LIalways report <code>NULL</code>. Without this, Expat has a smaller memory 437220ed979SColeman Kanefootprint and can be faster.</dd> 438220ed979SColeman Kane 4394543ef51SXin LI<dt><a name="XML_STATIC">XML_STATIC</a></dt> 440220ed979SColeman Kane<dd>On Windows, this should be set if Expat is going to be linked 441220ed979SColeman Kanestatically with the code that calls it; this is required to get all 442220ed979SColeman Kanethe right MSVC magic annotations correct. This is ignored on other 443220ed979SColeman Kaneplatforms.</dd> 444e3466a89SXin LI 4454543ef51SXin LI<dt><a name="XML_ATTR_INFO">XML_ATTR_INFO</a></dt> 4460a48773fSEric van Gyzen<dd>If defined, makes the additional function <code><a href= 447e3466a89SXin LI"#XML_GetAttributeInfo" >XML_GetAttributeInfo</a></code> available 448e3466a89SXin LIfor reporting attribute byte offsets.</dd> 449220ed979SColeman Kane</dl> 450220ed979SColeman Kane 4515bb6a25fSPoul-Henning Kamp<hr /> 4525bb6a25fSPoul-Henning Kamp<h2><a name="using">Using Expat</a></h2> 4535bb6a25fSPoul-Henning Kamp 4545bb6a25fSPoul-Henning Kamp<h3>Compiling and Linking Against Expat</h3> 4555bb6a25fSPoul-Henning Kamp 4565bb6a25fSPoul-Henning Kamp<p>Unless you installed Expat in a location not expected by your 4575bb6a25fSPoul-Henning Kampcompiler and linker, all you have to do to use Expat in your programs 4585bb6a25fSPoul-Henning Kampis to include the Expat header (<code>#include <expat.h></code>) 4595bb6a25fSPoul-Henning Kampin your files that make calls to it and to tell the linker that it 4605bb6a25fSPoul-Henning Kampneeds to link against the Expat library. On Unix systems, this would 4615bb6a25fSPoul-Henning Kampusually be done with the <code>-lexpat</code> argument. Otherwise, 4625bb6a25fSPoul-Henning Kampyou'll need to tell the compiler where to look for the Expat header 4635bb6a25fSPoul-Henning Kampand the linker where to find the Expat library. You may also need to 464220ed979SColeman Kanetake steps to tell the operating system where to find this library at 4655bb6a25fSPoul-Henning Kamprun time.</p> 4665bb6a25fSPoul-Henning Kamp 4675bb6a25fSPoul-Henning Kamp<p>On a Unix-based system, here's what a Makefile might look like when 4685bb6a25fSPoul-Henning KampExpat is installed in a standard location:</p> 4695bb6a25fSPoul-Henning Kamp 4705bb6a25fSPoul-Henning Kamp<pre class="eg"> 4715bb6a25fSPoul-Henning KampCC=cc 4725bb6a25fSPoul-Henning KampLDFLAGS= 4735bb6a25fSPoul-Henning KampLIBS= -lexpat 4745bb6a25fSPoul-Henning Kampxmlapp: xmlapp.o 4755bb6a25fSPoul-Henning Kamp $(CC) $(LDFLAGS) -o xmlapp xmlapp.o $(LIBS) 4765bb6a25fSPoul-Henning Kamp</pre> 4775bb6a25fSPoul-Henning Kamp 4785bb6a25fSPoul-Henning Kamp<p>If you installed Expat in, say, <code>/home/me/mystuff</code>, then 4795bb6a25fSPoul-Henning Kampthe Makefile would look like this:</p> 4805bb6a25fSPoul-Henning Kamp 4815bb6a25fSPoul-Henning Kamp<pre class="eg"> 4825bb6a25fSPoul-Henning KampCC=cc 4835bb6a25fSPoul-Henning KampCFLAGS= -I/home/me/mystuff/include 4845bb6a25fSPoul-Henning KampLDFLAGS= 4855bb6a25fSPoul-Henning KampLIBS= -L/home/me/mystuff/lib -lexpat 4865bb6a25fSPoul-Henning Kampxmlapp: xmlapp.o 4875bb6a25fSPoul-Henning Kamp $(CC) $(LDFLAGS) -o xmlapp xmlapp.o $(LIBS) 4885bb6a25fSPoul-Henning Kamp</pre> 4895bb6a25fSPoul-Henning Kamp 4905bb6a25fSPoul-Henning Kamp<p>You'd also have to set the environment variable 4915bb6a25fSPoul-Henning Kamp<code>LD_LIBRARY_PATH</code> to <code>/home/me/mystuff/lib</code> (or 4925bb6a25fSPoul-Henning Kampto <code>${LD_LIBRARY_PATH}:/home/me/mystuff/lib</code> if 4935bb6a25fSPoul-Henning KampLD_LIBRARY_PATH already has some directories in it) in order to run 4945bb6a25fSPoul-Henning Kampyour application.</p> 4955bb6a25fSPoul-Henning Kamp 4965bb6a25fSPoul-Henning Kamp<h3>Expat Basics</h3> 4975bb6a25fSPoul-Henning Kamp 4985bb6a25fSPoul-Henning Kamp<p>As we saw in the example in the overview, the first step in parsing 4995bb6a25fSPoul-Henning Kampan XML document with Expat is to create a parser object. There are <a 5005bb6a25fSPoul-Henning Kamphref="#creation">three functions</a> in the Expat API for creating a 5015bb6a25fSPoul-Henning Kampparser object. However, only two of these (<code><a href= 5025bb6a25fSPoul-Henning Kamp"#XML_ParserCreate" >XML_ParserCreate</a></code> and <code><a href= 5035bb6a25fSPoul-Henning Kamp"#XML_ParserCreateNS" >XML_ParserCreateNS</a></code>) can be used for 5045bb6a25fSPoul-Henning Kampconstructing a parser for a top-level document. The object returned 5055bb6a25fSPoul-Henning Kampby these functions is an opaque pointer (i.e. "expat.h" declares it as 5065bb6a25fSPoul-Henning Kampvoid *) to data with further internal structure. In order to free the 5075bb6a25fSPoul-Henning Kampmemory associated with this object you must call <code><a href= 5085bb6a25fSPoul-Henning Kamp"#XML_ParserFree" >XML_ParserFree</a></code>. Note that if you have 509220ed979SColeman Kaneprovided any <a href="#userdata">user data</a> that gets stored in the 5105bb6a25fSPoul-Henning Kampparser, then your application is responsible for freeing it prior to 5115bb6a25fSPoul-Henning Kampcalling <code>XML_ParserFree</code>.</p> 5125bb6a25fSPoul-Henning Kamp 5135bb6a25fSPoul-Henning Kamp<p>The objects returned by the parser creation functions are good for 5145bb6a25fSPoul-Henning Kampparsing only one XML document or external parsed entity. If your 5155bb6a25fSPoul-Henning Kampapplication needs to parse many XML documents, then it needs to create 5165bb6a25fSPoul-Henning Kampa parser object for each one. The best way to deal with this is to 5175bb6a25fSPoul-Henning Kampcreate a higher level object that contains all the default 5185bb6a25fSPoul-Henning Kampinitialization you want for your parser objects.</p> 5195bb6a25fSPoul-Henning Kamp 5205bb6a25fSPoul-Henning Kamp<p>Walking through a document hierarchy with a stream oriented parser 5215bb6a25fSPoul-Henning Kampwill require a good stack mechanism in order to keep track of current 5225bb6a25fSPoul-Henning Kampcontext. For instance, to answer the simple question, "What element 5235bb6a25fSPoul-Henning Kampdoes this text belong to?" requires a stack, since the parser may have 5245bb6a25fSPoul-Henning Kampdescended into other elements that are children of the current one and 5255bb6a25fSPoul-Henning Kamphas encountered this text on the way out.</p> 5265bb6a25fSPoul-Henning Kamp 5275bb6a25fSPoul-Henning Kamp<p>The things you're likely to want to keep on a stack are the 5285bb6a25fSPoul-Henning Kampcurrently opened element and it's attributes. You push this 5295bb6a25fSPoul-Henning Kampinformation onto the stack in the start handler and you pop it off in 5305bb6a25fSPoul-Henning Kampthe end handler.</p> 5315bb6a25fSPoul-Henning Kamp 5325bb6a25fSPoul-Henning Kamp<p>For some tasks, it is sufficient to just keep information on what 5335bb6a25fSPoul-Henning Kampthe depth of the stack is (or would be if you had one.) The outline 5345bb6a25fSPoul-Henning Kampprogram shown above presents one example. Another such task would be 5355bb6a25fSPoul-Henning Kampskipping over a complete element. When you see the start tag for the 5365bb6a25fSPoul-Henning Kampelement you want to skip, you set a skip flag and record the depth at 5375bb6a25fSPoul-Henning Kampwhich the element started. When the end tag handler encounters the 5385bb6a25fSPoul-Henning Kampsame depth, the skipped element has ended and the flag may be 5395bb6a25fSPoul-Henning Kampcleared. If you follow the convention that the root element starts at 5405bb6a25fSPoul-Henning Kamp1, then you can use the same variable for skip flag and skip 5415bb6a25fSPoul-Henning Kampdepth.</p> 5425bb6a25fSPoul-Henning Kamp 5435bb6a25fSPoul-Henning Kamp<pre class="eg"> 5445bb6a25fSPoul-Henning Kampvoid 5455bb6a25fSPoul-Henning Kampinit_info(Parseinfo *info) { 5465bb6a25fSPoul-Henning Kamp info->skip = 0; 5475bb6a25fSPoul-Henning Kamp info->depth = 1; 5485bb6a25fSPoul-Henning Kamp /* Other initializations here */ 5495bb6a25fSPoul-Henning Kamp} /* End of init_info */ 5505bb6a25fSPoul-Henning Kamp 551220ed979SColeman Kanevoid XMLCALL 5525bb6a25fSPoul-Henning Kamprawstart(void *data, const char *el, const char **attr) { 5535bb6a25fSPoul-Henning Kamp Parseinfo *inf = (Parseinfo *) data; 5545bb6a25fSPoul-Henning Kamp 5555bb6a25fSPoul-Henning Kamp if (! inf->skip) { 5565bb6a25fSPoul-Henning Kamp if (should_skip(inf, el, attr)) { 5575bb6a25fSPoul-Henning Kamp inf->skip = inf->depth; 5585bb6a25fSPoul-Henning Kamp } 5595bb6a25fSPoul-Henning Kamp else 5605bb6a25fSPoul-Henning Kamp start(inf, el, attr); /* This does rest of start handling */ 5615bb6a25fSPoul-Henning Kamp } 5625bb6a25fSPoul-Henning Kamp 5635bb6a25fSPoul-Henning Kamp inf->depth++; 5645bb6a25fSPoul-Henning Kamp} /* End of rawstart */ 5655bb6a25fSPoul-Henning Kamp 566220ed979SColeman Kanevoid XMLCALL 5675bb6a25fSPoul-Henning Kamprawend(void *data, const char *el) { 5685bb6a25fSPoul-Henning Kamp Parseinfo *inf = (Parseinfo *) data; 5695bb6a25fSPoul-Henning Kamp 5705bb6a25fSPoul-Henning Kamp inf->depth--; 5715bb6a25fSPoul-Henning Kamp 5725bb6a25fSPoul-Henning Kamp if (! inf->skip) 5735bb6a25fSPoul-Henning Kamp end(inf, el); /* This does rest of end handling */ 5745bb6a25fSPoul-Henning Kamp 5755bb6a25fSPoul-Henning Kamp if (inf->skip == inf->depth) 5765bb6a25fSPoul-Henning Kamp inf->skip = 0; 5775bb6a25fSPoul-Henning Kamp} /* End rawend */ 5785bb6a25fSPoul-Henning Kamp</pre> 5795bb6a25fSPoul-Henning Kamp 5805bb6a25fSPoul-Henning Kamp<p>Notice in the above example the difference in how depth is 5815bb6a25fSPoul-Henning Kampmanipulated in the start and end handlers. The end tag handler should 5825bb6a25fSPoul-Henning Kampbe the mirror image of the start tag handler. This is necessary to 5835bb6a25fSPoul-Henning Kampproperly model containment. Since, in the start tag handler, we 5845bb6a25fSPoul-Henning Kampincremented depth <em>after</em> the main body of start tag code, then 5855bb6a25fSPoul-Henning Kampin the end handler, we need to manipulate it <em>before</em> the main 5865bb6a25fSPoul-Henning Kampbody. If we'd decided to increment it first thing in the start 5875bb6a25fSPoul-Henning Kamphandler, then we'd have had to decrement it last thing in the end 5885bb6a25fSPoul-Henning Kamphandler.</p> 5895bb6a25fSPoul-Henning Kamp 5905bb6a25fSPoul-Henning Kamp<h3 id="userdata">Communicating between handlers</h3> 5915bb6a25fSPoul-Henning Kamp 5925bb6a25fSPoul-Henning Kamp<p>In order to be able to pass information between different handlers 5935bb6a25fSPoul-Henning Kampwithout using globals, you'll need to define a data structure to hold 5945bb6a25fSPoul-Henning Kampthe shared variables. You can then tell Expat (with the <code><a href= 5955bb6a25fSPoul-Henning Kamp"#XML_SetUserData" >XML_SetUserData</a></code> function) to pass a 596220ed979SColeman Kanepointer to this structure to the handlers. This is the first 597220ed979SColeman Kaneargument received by most handlers. In the <a href="#reference" 598220ed979SColeman Kane>reference section</a>, an argument to a callback function is named 599220ed979SColeman Kane<code>userData</code> and have type <code>void *</code> if the user 600220ed979SColeman Kanedata is passed; it will have the type <code>XML_Parser</code> if the 601220ed979SColeman Kaneparser itself is passed. When the parser is passed, the user data may 602220ed979SColeman Kanebe retrieved using <code><a href="#XML_GetUserData" 603220ed979SColeman Kane>XML_GetUserData</a></code>.</p> 604220ed979SColeman Kane 605220ed979SColeman Kane<p>One common case where multiple calls to a single handler may need 606220ed979SColeman Kaneto communicate using an application data structure is the case when 607220ed979SColeman Kanecontent passed to the character data handler (set by <code><a href= 608220ed979SColeman Kane"#XML_SetCharacterDataHandler" 609220ed979SColeman Kane>XML_SetCharacterDataHandler</a></code>) needs to be accumulated. A 610220ed979SColeman Kanecommon first-time mistake with any of the event-oriented interfaces to 611220ed979SColeman Kanean XML parser is to expect all the text contained in an element to be 612220ed979SColeman Kanereported by a single call to the character data handler. Expat, like 613220ed979SColeman Kanemany other XML parsers, reports such data as a sequence of calls; 614220ed979SColeman Kanethere's no way to know when the end of the sequence is reached until a 615220ed979SColeman Kanedifferent callback is made. A buffer referenced by the user data 616220ed979SColeman Kanestructure proves both an effective and convenient place to accumulate 617220ed979SColeman Kanecharacter data.</p> 618220ed979SColeman Kane 619220ed979SColeman Kane<!-- XXX example needed here --> 620220ed979SColeman Kane 6215bb6a25fSPoul-Henning Kamp 6225bb6a25fSPoul-Henning Kamp<h3>XML Version</h3> 6235bb6a25fSPoul-Henning Kamp 6245bb6a25fSPoul-Henning Kamp<p>Expat is an XML 1.0 parser, and as such never complains based on 6255bb6a25fSPoul-Henning Kampthe value of the <code>version</code> pseudo-attribute in the XML 6265bb6a25fSPoul-Henning Kampdeclaration, if present.</p> 6275bb6a25fSPoul-Henning Kamp 6285bb6a25fSPoul-Henning Kamp<p>If an application needs to check the version number (to support 6295bb6a25fSPoul-Henning Kampalternate processing), it should use the <code><a href= 6305bb6a25fSPoul-Henning Kamp"#XML_SetXmlDeclHandler" >XML_SetXmlDeclHandler</a></code> function to 6315bb6a25fSPoul-Henning Kampset a handler that uses the information in the XML declaration to 6325bb6a25fSPoul-Henning Kampdetermine what to do. This example shows how to check that only a 6335bb6a25fSPoul-Henning Kampversion number of <code>"1.0"</code> is accepted:</p> 6345bb6a25fSPoul-Henning Kamp 6355bb6a25fSPoul-Henning Kamp<pre class="eg"> 6365bb6a25fSPoul-Henning Kampstatic int wrong_version; 6375bb6a25fSPoul-Henning Kampstatic XML_Parser parser; 6385bb6a25fSPoul-Henning Kamp 639220ed979SColeman Kanestatic void XMLCALL 6405bb6a25fSPoul-Henning Kampxmldecl_handler(void *userData, 6415bb6a25fSPoul-Henning Kamp const XML_Char *version, 6425bb6a25fSPoul-Henning Kamp const XML_Char *encoding, 6435bb6a25fSPoul-Henning Kamp int standalone) 6445bb6a25fSPoul-Henning Kamp{ 6455bb6a25fSPoul-Henning Kamp static const XML_Char Version_1_0[] = {'1', '.', '0', 0}; 6465bb6a25fSPoul-Henning Kamp 6475bb6a25fSPoul-Henning Kamp int i; 6485bb6a25fSPoul-Henning Kamp 6495bb6a25fSPoul-Henning Kamp for (i = 0; i < (sizeof(Version_1_0) / sizeof(Version_1_0[0])); ++i) { 6505bb6a25fSPoul-Henning Kamp if (version[i] != Version_1_0[i]) { 6515bb6a25fSPoul-Henning Kamp wrong_version = 1; 6525bb6a25fSPoul-Henning Kamp /* also clear all other handlers: */ 6535bb6a25fSPoul-Henning Kamp XML_SetCharacterDataHandler(parser, NULL); 6545bb6a25fSPoul-Henning Kamp ... 6555bb6a25fSPoul-Henning Kamp return; 6565bb6a25fSPoul-Henning Kamp } 6575bb6a25fSPoul-Henning Kamp } 6585bb6a25fSPoul-Henning Kamp ... 6595bb6a25fSPoul-Henning Kamp} 6605bb6a25fSPoul-Henning Kamp</pre> 6615bb6a25fSPoul-Henning Kamp 6625bb6a25fSPoul-Henning Kamp<h3>Namespace Processing</h3> 6635bb6a25fSPoul-Henning Kamp 6645bb6a25fSPoul-Henning Kamp<p>When the parser is created using the <code><a href= 6655bb6a25fSPoul-Henning Kamp"#XML_ParserCreateNS" >XML_ParserCreateNS</a></code>, function, Expat 6665bb6a25fSPoul-Henning Kampperforms namespace processing. Under namespace processing, Expat 6675bb6a25fSPoul-Henning Kampconsumes <code>xmlns</code> and <code>xmlns:...</code> attributes, 6685bb6a25fSPoul-Henning Kampwhich declare namespaces for the scope of the element in which they 6695bb6a25fSPoul-Henning Kampoccur. This means that your start handler will not see these 6705bb6a25fSPoul-Henning Kampattributes. Your application can still be informed of these 6715bb6a25fSPoul-Henning Kampdeclarations by setting namespace declaration handlers with <a href= 6725bb6a25fSPoul-Henning Kamp"#XML_SetNamespaceDeclHandler" 6735bb6a25fSPoul-Henning Kamp><code>XML_SetNamespaceDeclHandler</code></a>.</p> 6745bb6a25fSPoul-Henning Kamp 6755bb6a25fSPoul-Henning Kamp<p>Element type and attribute names that belong to a given namespace 6765bb6a25fSPoul-Henning Kampare passed to the appropriate handler in expanded form. By default 6775bb6a25fSPoul-Henning Kampthis expanded form is a concatenation of the namespace URI, the 6785bb6a25fSPoul-Henning Kampseparator character (which is the 2nd argument to <code><a href= 6795bb6a25fSPoul-Henning Kamp"#XML_ParserCreateNS" >XML_ParserCreateNS</a></code>), and the local 6805bb6a25fSPoul-Henning Kampname (i.e. the part after the colon). Names with undeclared prefixes 681220ed979SColeman Kaneare not well-formed when namespace processing is enabled, and will 682220ed979SColeman Kanetrigger an error. Unprefixed attribute names are never expanded, 6835bb6a25fSPoul-Henning Kampand unprefixed element names are only expanded when they are in the 6845bb6a25fSPoul-Henning Kampscope of a default namespace.</p> 6855bb6a25fSPoul-Henning Kamp 686220ed979SColeman Kane<p>However if <code><a href= "#XML_SetReturnNSTriplet" 6875bb6a25fSPoul-Henning Kamp>XML_SetReturnNSTriplet</a></code> has been called with a non-zero 6885bb6a25fSPoul-Henning Kamp<code>do_nst</code> parameter, then the expanded form for names with 6895bb6a25fSPoul-Henning Kampan explicit prefix is a concatenation of: URI, separator, local name, 6905bb6a25fSPoul-Henning Kampseparator, prefix.</p> 6915bb6a25fSPoul-Henning Kamp 6925bb6a25fSPoul-Henning Kamp<p>You can set handlers for the start of a namespace declaration and 6935bb6a25fSPoul-Henning Kampfor the end of a scope of a declaration with the <code><a href= 6945bb6a25fSPoul-Henning Kamp"#XML_SetNamespaceDeclHandler" >XML_SetNamespaceDeclHandler</a></code> 6955bb6a25fSPoul-Henning Kampfunction. The StartNamespaceDeclHandler is called prior to the start 696220ed979SColeman Kanetag handler and the EndNamespaceDeclHandler is called after the 6975bb6a25fSPoul-Henning Kampcorresponding end tag that ends the namespace's scope. The namespace 6985bb6a25fSPoul-Henning Kampstart handler gets passed the prefix and URI for the namespace. For a 6994543ef51SXin LIdefault namespace declaration (xmlns='...'), the prefix will be 7004543ef51SXin LI<code>NULL</code>. 7014543ef51SXin LIThe URI will be <code>NULL</code> for the case where the default namespace is being 7025bb6a25fSPoul-Henning Kampunset. The namespace end handler just gets the prefix for the closing 7035bb6a25fSPoul-Henning Kampscope.</p> 7045bb6a25fSPoul-Henning Kamp 7055bb6a25fSPoul-Henning Kamp<p>These handlers are called for each declaration. So if, for 7065bb6a25fSPoul-Henning Kampinstance, a start tag had three namespace declarations, then the 7075bb6a25fSPoul-Henning KampStartNamespaceDeclHandler would be called three times before the start 7085bb6a25fSPoul-Henning Kamptag handler is called, once for each declaration.</p> 7095bb6a25fSPoul-Henning Kamp 7105bb6a25fSPoul-Henning Kamp<h3>Character Encodings</h3> 7115bb6a25fSPoul-Henning Kamp 7125bb6a25fSPoul-Henning Kamp<p>While XML is based on Unicode, and every XML processor is required 7135bb6a25fSPoul-Henning Kampto recognized UTF-8 and UTF-16 (1 and 2 byte encodings of Unicode), 7145bb6a25fSPoul-Henning Kampother encodings may be declared in XML documents or entities. For the 7155bb6a25fSPoul-Henning Kampmain document, an XML declaration may contain an encoding 7165bb6a25fSPoul-Henning Kampdeclaration:</p> 7175bb6a25fSPoul-Henning Kamp<pre> 7185bb6a25fSPoul-Henning Kamp<?xml version="1.0" encoding="ISO-8859-2"?> 7195bb6a25fSPoul-Henning Kamp</pre> 7205bb6a25fSPoul-Henning Kamp 7215bb6a25fSPoul-Henning Kamp<p>External parsed entities may begin with a text declaration, which 7225bb6a25fSPoul-Henning Kamplooks like an XML declaration with just an encoding declaration:</p> 7235bb6a25fSPoul-Henning Kamp<pre> 7245bb6a25fSPoul-Henning Kamp<?xml encoding="Big5"?> 7255bb6a25fSPoul-Henning Kamp</pre> 7265bb6a25fSPoul-Henning Kamp 7275bb6a25fSPoul-Henning Kamp<p>With Expat, you may also specify an encoding at the time of 7285bb6a25fSPoul-Henning Kampcreating a parser. This is useful when the encoding information may 7295bb6a25fSPoul-Henning Kampcome from a source outside the document itself (like a higher level 7305bb6a25fSPoul-Henning Kampprotocol.)</p> 7315bb6a25fSPoul-Henning Kamp 7325bb6a25fSPoul-Henning Kamp<p><a name="builtin_encodings"></a>There are four built-in encodings 7335bb6a25fSPoul-Henning Kampin Expat:</p> 7345bb6a25fSPoul-Henning Kamp<ul> 7355bb6a25fSPoul-Henning Kamp<li>UTF-8</li> 7365bb6a25fSPoul-Henning Kamp<li>UTF-16</li> 7375bb6a25fSPoul-Henning Kamp<li>ISO-8859-1</li> 7385bb6a25fSPoul-Henning Kamp<li>US-ASCII</li> 7395bb6a25fSPoul-Henning Kamp</ul> 7405bb6a25fSPoul-Henning Kamp 7415bb6a25fSPoul-Henning Kamp<p>Anything else discovered in an encoding declaration or in the 7425bb6a25fSPoul-Henning Kampprotocol encoding specified in the parser constructor, triggers a call 7435bb6a25fSPoul-Henning Kampto the <code>UnknownEncodingHandler</code>. This handler gets passed 7445bb6a25fSPoul-Henning Kampthe encoding name and a pointer to an <code>XML_Encoding</code> data 745220ed979SColeman Kanestructure. Your handler must fill in this structure and return 746220ed979SColeman Kane<code>XML_STATUS_OK</code> if it knows how to deal with the 747220ed979SColeman Kaneencoding. Otherwise the handler should return 748220ed979SColeman Kane<code>XML_STATUS_ERROR</code>. The handler also gets passed a pointer 749220ed979SColeman Kaneto an optional application data structure that you may indicate when 750220ed979SColeman Kaneyou set the handler.</p> 7515bb6a25fSPoul-Henning Kamp 7525bb6a25fSPoul-Henning Kamp<p>Expat places restrictions on character encodings that it can 7535bb6a25fSPoul-Henning Kampsupport by filling in the <code>XML_Encoding</code> structure. 7545bb6a25fSPoul-Henning Kampinclude file:</p> 7555bb6a25fSPoul-Henning Kamp<ol> 7565bb6a25fSPoul-Henning Kamp<li>Every ASCII character that can appear in a well-formed XML document 7575bb6a25fSPoul-Henning Kampmust be represented by a single byte, and that byte must correspond to 7585bb6a25fSPoul-Henning Kampit's ASCII encoding (except for the characters $@\^'{}~)</li> 7595bb6a25fSPoul-Henning Kamp<li>Characters must be encoded in 4 bytes or less.</li> 7605bb6a25fSPoul-Henning Kamp<li>All characters encoded must have Unicode scalar values less than or 7615bb6a25fSPoul-Henning Kampequal to 65535 (0xFFFF)<em>This does not apply to the built-in support 7625bb6a25fSPoul-Henning Kampfor UTF-16 and UTF-8</em></li> 7635bb6a25fSPoul-Henning Kamp<li>No character may be encoded by more that one distinct sequence of 7645bb6a25fSPoul-Henning Kampbytes</li> 7655bb6a25fSPoul-Henning Kamp</ol> 7665bb6a25fSPoul-Henning Kamp 7675bb6a25fSPoul-Henning Kamp<p><code>XML_Encoding</code> contains an array of integers that 7685bb6a25fSPoul-Henning Kampcorrespond to the 1st byte of an encoding sequence. If the value in 7695bb6a25fSPoul-Henning Kampthe array for a byte is zero or positive, then the byte is a single 7705bb6a25fSPoul-Henning Kampbyte encoding that encodes the Unicode scalar value contained in the 7715bb6a25fSPoul-Henning Kamparray. A -1 in this array indicates a malformed byte. If the value is 7725bb6a25fSPoul-Henning Kamp-2, -3, or -4, then the byte is the beginning of a 2, 3, or 4 byte 7735bb6a25fSPoul-Henning Kampsequence respectively. Multi-byte sequences are sent to the convert 7745bb6a25fSPoul-Henning Kampfunction pointed at in the <code>XML_Encoding</code> structure. This 7755bb6a25fSPoul-Henning Kampfunction should return the Unicode scalar value for the sequence or -1 7765bb6a25fSPoul-Henning Kampif the sequence is malformed.</p> 7775bb6a25fSPoul-Henning Kamp 7785bb6a25fSPoul-Henning Kamp<p>One pitfall that novice Expat users are likely to fall into is that 7795bb6a25fSPoul-Henning Kampalthough Expat may accept input in various encodings, the strings that 7805bb6a25fSPoul-Henning Kampit passes to the handlers are always encoded in UTF-8 or UTF-16 7815bb6a25fSPoul-Henning Kamp(depending on how Expat was compiled). Your application is responsible 7825bb6a25fSPoul-Henning Kampfor any translation of these strings into other encodings.</p> 7835bb6a25fSPoul-Henning Kamp 7845bb6a25fSPoul-Henning Kamp<h3>Handling External Entity References</h3> 7855bb6a25fSPoul-Henning Kamp 7865bb6a25fSPoul-Henning Kamp<p>Expat does not read or parse external entities directly. Note that 7875bb6a25fSPoul-Henning Kampany external DTD is a special case of an external entity. If you've 7885bb6a25fSPoul-Henning Kampset no <code>ExternalEntityRefHandler</code>, then external entity 7895bb6a25fSPoul-Henning Kampreferences are silently ignored. Otherwise, it calls your handler with 7905bb6a25fSPoul-Henning Kampthe information needed to read and parse the external entity.</p> 7915bb6a25fSPoul-Henning Kamp 7925bb6a25fSPoul-Henning Kamp<p>Your handler isn't actually responsible for parsing the entity, but 7935bb6a25fSPoul-Henning Kampit is responsible for creating a subsidiary parser with <code><a href= 7945bb6a25fSPoul-Henning Kamp"#XML_ExternalEntityParserCreate" 7955bb6a25fSPoul-Henning Kamp>XML_ExternalEntityParserCreate</a></code> that will do the job. This 7965bb6a25fSPoul-Henning Kampreturns an instance of <code>XML_Parser</code> that has handlers and 7975bb6a25fSPoul-Henning Kampother data structures initialized from the parent parser. You may then 7985bb6a25fSPoul-Henning Kampuse <code><a href= "#XML_Parse" >XML_Parse</a></code> or <code><a 7995bb6a25fSPoul-Henning Kamphref= "#XML_ParseBuffer">XML_ParseBuffer</a></code> calls against this 8005bb6a25fSPoul-Henning Kampparser. Since external entities my refer to other external entities, 8015bb6a25fSPoul-Henning Kampyour handler should be prepared to be called recursively.</p> 8025bb6a25fSPoul-Henning Kamp 8035bb6a25fSPoul-Henning Kamp<h3>Parsing DTDs</h3> 8045bb6a25fSPoul-Henning Kamp 8055bb6a25fSPoul-Henning Kamp<p>In order to parse parameter entities, before starting the parse, 8065bb6a25fSPoul-Henning Kampyou must call <code><a href= "#XML_SetParamEntityParsing" 8075bb6a25fSPoul-Henning Kamp>XML_SetParamEntityParsing</a></code> with one of the following 8085bb6a25fSPoul-Henning Kamparguments:</p> 8095bb6a25fSPoul-Henning Kamp<dl> 8105bb6a25fSPoul-Henning Kamp<dt><code>XML_PARAM_ENTITY_PARSING_NEVER</code></dt> 8115bb6a25fSPoul-Henning Kamp<dd>Don't parse parameter entities or the external subset</dd> 8125bb6a25fSPoul-Henning Kamp<dt><code>XML_PARAM_ENTITY_PARSING_UNLESS_STANDALONE</code></dt> 8130a48773fSEric van Gyzen<dd>Parse parameter entities and the external subset unless 8145bb6a25fSPoul-Henning Kamp<code>standalone</code> was set to "yes" in the XML declaration.</dd> 8155bb6a25fSPoul-Henning Kamp<dt><code>XML_PARAM_ENTITY_PARSING_ALWAYS</code></dt> 8165bb6a25fSPoul-Henning Kamp<dd>Always parse parameter entities and the external subset</dd> 8175bb6a25fSPoul-Henning Kamp</dl> 8185bb6a25fSPoul-Henning Kamp 8195bb6a25fSPoul-Henning Kamp<p>In order to read an external DTD, you also have to set an external 8205bb6a25fSPoul-Henning Kampentity reference handler as described above.</p> 8215bb6a25fSPoul-Henning Kamp 822220ed979SColeman Kane<h3 id="stop-resume">Temporarily Stopping Parsing</h3> 823220ed979SColeman Kane 824220ed979SColeman Kane<p>Expat 1.95.8 introduces a new feature: its now possible to stop 825220ed979SColeman Kaneparsing temporarily from within a handler function, even if more data 826220ed979SColeman Kanehas already been passed into the parser. Applications for this 827220ed979SColeman Kaneinclude</p> 828220ed979SColeman Kane 829220ed979SColeman Kane<ul> 8304543ef51SXin LI <li>Supporting the <a href= "https://www.w3.org/TR/xinclude/" 831220ed979SColeman Kane >XInclude</a> specification.</li> 832220ed979SColeman Kane 833220ed979SColeman Kane <li>Delaying further processing until additional information is 834220ed979SColeman Kane available from some other source.</li> 835220ed979SColeman Kane 836220ed979SColeman Kane <li>Adjusting processor load as task priorities shift within an 837220ed979SColeman Kane application.</li> 838220ed979SColeman Kane 839220ed979SColeman Kane <li>Stopping parsing completely (simply free or reset the parser 840220ed979SColeman Kane instead of resuming in the outer parsing loop). This can be useful 8410a48773fSEric van Gyzen if an application-domain error is found in the XML being parsed or if 842220ed979SColeman Kane the result of the parse is determined not to be useful after 843220ed979SColeman Kane all.</li> 844220ed979SColeman Kane</ul> 845220ed979SColeman Kane 846220ed979SColeman Kane<p>To take advantage of this feature, the main parsing loop of an 847220ed979SColeman Kaneapplication needs to support this specifically. It cannot be 848220ed979SColeman Kanesupported with a parsing loop compatible with Expat 1.95.7 or 849220ed979SColeman Kaneearlier (though existing loops will continue to work without 850220ed979SColeman Kanesupporting the stop/resume feature).</p> 851220ed979SColeman Kane 852220ed979SColeman Kane<p>An application that uses this feature for a single parser will have 853220ed979SColeman Kanethe rough structure (in pseudo-code):</p> 854220ed979SColeman Kane 855220ed979SColeman Kane<pre class="pseudocode"> 856220ed979SColeman Kanefd = open_input() 857220ed979SColeman Kanep = create_parser() 858220ed979SColeman Kane 859220ed979SColeman Kaneif parse_xml(p, fd) { 860220ed979SColeman Kane /* suspended */ 861220ed979SColeman Kane 862220ed979SColeman Kane int suspended = 1; 863220ed979SColeman Kane 864220ed979SColeman Kane while (suspended) { 865220ed979SColeman Kane do_something_else() 866220ed979SColeman Kane if ready_to_resume() { 867220ed979SColeman Kane suspended = continue_parsing(p, fd); 868220ed979SColeman Kane } 869220ed979SColeman Kane } 870220ed979SColeman Kane} 871220ed979SColeman Kane</pre> 872220ed979SColeman Kane 873220ed979SColeman Kane<p>An application that may resume any of several parsers based on 874220ed979SColeman Kaneinput (either from the XML being parsed or some other source) will 875220ed979SColeman Kanecertainly have more interesting control structures.</p> 876220ed979SColeman Kane 877220ed979SColeman Kane<p>This C function could be used for the <code>parse_xml</code> 878220ed979SColeman Kanefunction mentioned in the pseudo-code above:</p> 879220ed979SColeman Kane 880220ed979SColeman Kane<pre class="eg"> 881220ed979SColeman Kane#define BUFF_SIZE 10240 882220ed979SColeman Kane 883220ed979SColeman Kane/* Parse a document from the open file descriptor 'fd' until the parse 884220ed979SColeman Kane is complete (the document has been completely parsed, or there's 885220ed979SColeman Kane been an error), or the parse is stopped. Return non-zero when 886220ed979SColeman Kane the parse is merely suspended. 887220ed979SColeman Kane*/ 888220ed979SColeman Kaneint 889220ed979SColeman Kaneparse_xml(XML_Parser p, int fd) 890220ed979SColeman Kane{ 891220ed979SColeman Kane for (;;) { 892220ed979SColeman Kane int last_chunk; 893220ed979SColeman Kane int bytes_read; 894220ed979SColeman Kane enum XML_Status status; 895220ed979SColeman Kane 896220ed979SColeman Kane void *buff = XML_GetBuffer(p, BUFF_SIZE); 897220ed979SColeman Kane if (buff == NULL) { 898220ed979SColeman Kane /* handle error... */ 899220ed979SColeman Kane return 0; 900220ed979SColeman Kane } 901220ed979SColeman Kane bytes_read = read(fd, buff, BUFF_SIZE); 902220ed979SColeman Kane if (bytes_read < 0) { 903220ed979SColeman Kane /* handle error... */ 904220ed979SColeman Kane return 0; 905220ed979SColeman Kane } 906220ed979SColeman Kane status = XML_ParseBuffer(p, bytes_read, bytes_read == 0); 907220ed979SColeman Kane switch (status) { 908220ed979SColeman Kane case XML_STATUS_ERROR: 909220ed979SColeman Kane /* handle error... */ 910220ed979SColeman Kane return 0; 911220ed979SColeman Kane case XML_STATUS_SUSPENDED: 912220ed979SColeman Kane return 1; 913220ed979SColeman Kane } 914220ed979SColeman Kane if (bytes_read == 0) 915220ed979SColeman Kane return 0; 916220ed979SColeman Kane } 917220ed979SColeman Kane} 918220ed979SColeman Kane</pre> 919220ed979SColeman Kane 920220ed979SColeman Kane<p>The corresponding <code>continue_parsing</code> function is 921220ed979SColeman Kanesomewhat simpler, since it only need deal with the return code from 922220ed979SColeman Kane<code><a href= "#XML_ResumeParser">XML_ResumeParser</a></code>; it can 923220ed979SColeman Kanedelegate the input handling to the <code>parse_xml</code> 924220ed979SColeman Kanefunction:</p> 925220ed979SColeman Kane 926220ed979SColeman Kane<pre class="eg"> 927220ed979SColeman Kane/* Continue parsing a document which had been suspended. The 'p' and 928220ed979SColeman Kane 'fd' arguments are the same as passed to parse_xml(). Return 929220ed979SColeman Kane non-zero when the parse is suspended. 930220ed979SColeman Kane*/ 931220ed979SColeman Kaneint 932220ed979SColeman Kanecontinue_parsing(XML_Parser p, int fd) 933220ed979SColeman Kane{ 934220ed979SColeman Kane enum XML_Status status = XML_ResumeParser(p); 935220ed979SColeman Kane switch (status) { 936220ed979SColeman Kane case XML_STATUS_ERROR: 937220ed979SColeman Kane /* handle error... */ 938220ed979SColeman Kane return 0; 939220ed979SColeman Kane case XML_ERROR_NOT_SUSPENDED: 940220ed979SColeman Kane /* handle error... */ 941220ed979SColeman Kane return 0;. 942220ed979SColeman Kane case XML_STATUS_SUSPENDED: 943220ed979SColeman Kane return 1; 944220ed979SColeman Kane } 945220ed979SColeman Kane return parse_xml(p, fd); 946220ed979SColeman Kane} 947220ed979SColeman Kane</pre> 948220ed979SColeman Kane 949220ed979SColeman Kane<p>Now that we've seen what a mess the top-level parsing loop can 950220ed979SColeman Kanebecome, what have we gained? Very simply, we can now use the <code><a 951220ed979SColeman Kanehref= "#XML_StopParser" >XML_StopParser</a></code> function to stop 952220ed979SColeman Kaneparsing, without having to go to great lengths to avoid additional 953220ed979SColeman Kaneprocessing that we're expecting to ignore. As a bonus, we get to stop 954220ed979SColeman Kaneparsing <em>temporarily</em>, and come back to it when we're 955220ed979SColeman Kaneready.</p> 956220ed979SColeman Kane 957220ed979SColeman Kane<p>To stop parsing from a handler function, use the <code><a href= 958220ed979SColeman Kane"#XML_StopParser" >XML_StopParser</a></code> function. This function 959220ed979SColeman Kanetakes two arguments; the parser being stopped and a flag indicating 960220ed979SColeman Kanewhether the parse can be resumed in the future.</p> 961220ed979SColeman Kane 962220ed979SColeman Kane<!-- XXX really need more here --> 963220ed979SColeman Kane 964220ed979SColeman Kane 9655bb6a25fSPoul-Henning Kamp<hr /> 9665bb6a25fSPoul-Henning Kamp<!-- ================================================================ --> 9675bb6a25fSPoul-Henning Kamp 9685bb6a25fSPoul-Henning Kamp<h2><a name="reference">Expat Reference</a></h2> 9695bb6a25fSPoul-Henning Kamp 9705bb6a25fSPoul-Henning Kamp<h3><a name="creation">Parser Creation</a></h3> 9715bb6a25fSPoul-Henning Kamp 972cc68614dSXin LI<h4 id="XML_ParserCreate">XML_ParserCreate</h4> 973cc68614dSXin LI<pre class="fcndec"> 974220ed979SColeman KaneXML_Parser XMLCALL 9755bb6a25fSPoul-Henning KampXML_ParserCreate(const XML_Char *encoding); 9765bb6a25fSPoul-Henning Kamp</pre> 9775bb6a25fSPoul-Henning Kamp<div class="fcndef"> 9784543ef51SXin LI<p> 9794543ef51SXin LIConstruct a new parser. If encoding is non-<code>NULL</code>, it specifies a 9805bb6a25fSPoul-Henning Kampcharacter encoding to use for the document. This overrides the document 9815bb6a25fSPoul-Henning Kampencoding declaration. There are four built-in encodings: 9824543ef51SXin LI</p> 9835bb6a25fSPoul-Henning Kamp<ul> 9845bb6a25fSPoul-Henning Kamp<li>US-ASCII</li> 9855bb6a25fSPoul-Henning Kamp<li>UTF-8</li> 9865bb6a25fSPoul-Henning Kamp<li>UTF-16</li> 9875bb6a25fSPoul-Henning Kamp<li>ISO-8859-1</li> 9885bb6a25fSPoul-Henning Kamp</ul> 9894543ef51SXin LI<p> 9905bb6a25fSPoul-Henning KampAny other value will invoke a call to the UnknownEncodingHandler. 9914543ef51SXin LI</p> 9925bb6a25fSPoul-Henning Kamp</div> 9935bb6a25fSPoul-Henning Kamp 994cc68614dSXin LI<h4 id="XML_ParserCreateNS">XML_ParserCreateNS</h4> 995cc68614dSXin LI<pre class="fcndec"> 996220ed979SColeman KaneXML_Parser XMLCALL 9975bb6a25fSPoul-Henning KampXML_ParserCreateNS(const XML_Char *encoding, 9985bb6a25fSPoul-Henning Kamp XML_Char sep); 9995bb6a25fSPoul-Henning Kamp</pre> 10005bb6a25fSPoul-Henning Kamp<div class="fcndef"> 10015bb6a25fSPoul-Henning KampConstructs a new parser that has namespace processing in effect. Namespace 10025bb6a25fSPoul-Henning Kampexpanded element names and attribute names are returned as a concatenation 10035bb6a25fSPoul-Henning Kampof the namespace URI, <em>sep</em>, and the local part of the name. This 1004e3466a89SXin LImeans that you should pick a character for <em>sep</em> that can't be part 1005e3466a89SXin LIof an URI. Since Expat does not check namespace URIs for conformance, the 1006e3466a89SXin LIonly safe choice for a namespace separator is a character that is illegal 1007e3466a89SXin LIin XML. For instance, <code>'\xFF'</code> is not legal in UTF-8, and 1008e3466a89SXin LI<code>'\xFFFF'</code> is not legal in UTF-16. There is a special case when 1009e3466a89SXin LI<em>sep</em> is the null character <code>'\0'</code>: the namespace URI and 1010e3466a89SXin LIthe local part will be concatenated without any separator - this is intended 1011e3466a89SXin LIto support RDF processors. It is a programming error to use the null separator 1012e3466a89SXin LIwith <a href= "#XML_SetReturnNSTriplet">namespace triplets</a>.</div> 10135bb6a25fSPoul-Henning Kamp 10147ed8e142SXin LI<p><strong>Note:</strong> 10157ed8e142SXin LIExpat does not validate namespace URIs (beyond encoding) 10167ed8e142SXin LIagainst RFC 3986 today (and is not required to do so with regard to 10177ed8e142SXin LIthe XML 1.0 namespaces specification) but it may start doing that 10187ed8e142SXin LIin future releases. Before that, an application using Expat must 10197ed8e142SXin LIbe ready to receive namespace URIs containing non-URI characters. 10207ed8e142SXin LI</p> 10217ed8e142SXin LI 1022cc68614dSXin LI<h4 id="XML_ParserCreate_MM">XML_ParserCreate_MM</h4> 1023cc68614dSXin LI<pre class="fcndec"> 1024220ed979SColeman KaneXML_Parser XMLCALL 10255bb6a25fSPoul-Henning KampXML_ParserCreate_MM(const XML_Char *encoding, 10265bb6a25fSPoul-Henning Kamp const XML_Memory_Handling_Suite *ms, 10275bb6a25fSPoul-Henning Kamp const XML_Char *sep); 10285bb6a25fSPoul-Henning Kamp</pre> 10295bb6a25fSPoul-Henning Kamp<pre class="signature"> 10305bb6a25fSPoul-Henning Kamptypedef struct { 1031220ed979SColeman Kane void *(XMLCALL *malloc_fcn)(size_t size); 1032220ed979SColeman Kane void *(XMLCALL *realloc_fcn)(void *ptr, size_t size); 1033220ed979SColeman Kane void (XMLCALL *free_fcn)(void *ptr); 10345bb6a25fSPoul-Henning Kamp} XML_Memory_Handling_Suite; 10355bb6a25fSPoul-Henning Kamp</pre> 10365bb6a25fSPoul-Henning Kamp<div class="fcndef"> 10375bb6a25fSPoul-Henning Kamp<p>Construct a new parser using the suite of memory handling functions 10384543ef51SXin LIspecified in <code>ms</code>. If <code>ms</code> is <code>NULL</code>, then use the 10395bb6a25fSPoul-Henning Kampstandard set of memory management functions. If <code>sep</code> is 10404543ef51SXin LInon-<code>NULL</code>, then namespace processing is enabled in the created parser 10415bb6a25fSPoul-Henning Kampand the character pointed at by sep is used as the separator between 10425bb6a25fSPoul-Henning Kampthe namespace URI and the local part of the name.</p> 10435bb6a25fSPoul-Henning Kamp</div> 10445bb6a25fSPoul-Henning Kamp 1045cc68614dSXin LI<h4 id="XML_ExternalEntityParserCreate">XML_ExternalEntityParserCreate</h4> 1046cc68614dSXin LI<pre class="fcndec"> 1047220ed979SColeman KaneXML_Parser XMLCALL 10485bb6a25fSPoul-Henning KampXML_ExternalEntityParserCreate(XML_Parser p, 10495bb6a25fSPoul-Henning Kamp const XML_Char *context, 10505bb6a25fSPoul-Henning Kamp const XML_Char *encoding); 10515bb6a25fSPoul-Henning Kamp</pre> 10525bb6a25fSPoul-Henning Kamp<div class="fcndef"> 10535bb6a25fSPoul-Henning KampConstruct a new <code>XML_Parser</code> object for parsing an external 10545bb6a25fSPoul-Henning Kampgeneral entity. Context is the context argument passed in a call to a 10555bb6a25fSPoul-Henning KampExternalEntityRefHandler. Other state information such as handlers, 10565bb6a25fSPoul-Henning Kampuser data, namespace processing is inherited from the parser passed as 10575bb6a25fSPoul-Henning Kampthe 1st argument. So you shouldn't need to call any of the behavior 10585bb6a25fSPoul-Henning Kampchanging functions on this parser (unless you want it to act 10595bb6a25fSPoul-Henning Kampdifferently than the parent parser). 10605bb6a25fSPoul-Henning Kamp</div> 10615bb6a25fSPoul-Henning Kamp 1062cc68614dSXin LI<h4 id="XML_ParserFree">XML_ParserFree</h4> 1063cc68614dSXin LI<pre class="fcndec"> 1064220ed979SColeman Kanevoid XMLCALL 10655bb6a25fSPoul-Henning KampXML_ParserFree(XML_Parser p); 10665bb6a25fSPoul-Henning Kamp</pre> 10675bb6a25fSPoul-Henning Kamp<div class="fcndef"> 10685bb6a25fSPoul-Henning KampFree memory used by the parser. Your application is responsible for 10695bb6a25fSPoul-Henning Kampfreeing any memory associated with <a href="#userdata">user data</a>. 10705bb6a25fSPoul-Henning Kamp</div> 10715bb6a25fSPoul-Henning Kamp 1072cc68614dSXin LI<h4 id="XML_ParserReset">XML_ParserReset</h4> 1073cc68614dSXin LI<pre class="fcndec"> 1074220ed979SColeman KaneXML_Bool XMLCALL 1075220ed979SColeman KaneXML_ParserReset(XML_Parser p, 1076220ed979SColeman Kane const XML_Char *encoding); 10775bb6a25fSPoul-Henning Kamp</pre> 10785bb6a25fSPoul-Henning Kamp<div class="fcndef"> 10795bb6a25fSPoul-Henning KampClean up the memory structures maintained by the parser so that it may 10805bb6a25fSPoul-Henning Kampbe used again. After this has been called, <code>parser</code> is 1081220ed979SColeman Kaneready to start parsing a new document. All handlers are cleared from 1082220ed979SColeman Kanethe parser, except for the unknownEncodingHandler. The parser's external 1083220ed979SColeman Kanestate is re-initialized except for the values of ns and ns_triplets. 1084220ed979SColeman KaneThis function may not be used on a parser created using <code><a href= 10855bb6a25fSPoul-Henning Kamp"#XML_ExternalEntityParserCreate" >XML_ExternalEntityParserCreate</a 10865bb6a25fSPoul-Henning Kamp></code>; it will return <code>XML_FALSE</code> in that case. Returns 10875bb6a25fSPoul-Henning Kamp<code>XML_TRUE</code> on success. Your application is responsible for 10885bb6a25fSPoul-Henning Kampdealing with any memory associated with <a href="#userdata">user data</a>. 10895bb6a25fSPoul-Henning Kamp</div> 10905bb6a25fSPoul-Henning Kamp 10915bb6a25fSPoul-Henning Kamp<h3><a name="parsing">Parsing</a></h3> 10925bb6a25fSPoul-Henning Kamp 10935bb6a25fSPoul-Henning Kamp<p>To state the obvious: the three parsing functions <code><a href= 1094220ed979SColeman Kane"#XML_Parse" >XML_Parse</a></code>, <code><a href= "#XML_ParseBuffer"> 1095220ed979SColeman KaneXML_ParseBuffer</a></code> and <code><a href= "#XML_GetBuffer"> 1096220ed979SColeman KaneXML_GetBuffer</a></code> must not be called from within a handler 1097220ed979SColeman Kaneunless they operate on a separate parser instance, that is, one that 1098220ed979SColeman Kanedid not call the handler. For example, it is OK to call the parsing 1099220ed979SColeman Kanefunctions from within an <code>XML_ExternalEntityRefHandler</code>, 1100220ed979SColeman Kaneif they apply to the parser created by 1101220ed979SColeman Kane<code><a href= "#XML_ExternalEntityParserCreate" 11025bb6a25fSPoul-Henning Kamp>XML_ExternalEntityParserCreate</a></code>.</p> 11035bb6a25fSPoul-Henning Kamp 1104cc68614dSXin LI<p>Note: The <code>len</code> argument passed to these functions 1105220ed979SColeman Kaneshould be considerably less than the maximum value for an integer, 1106220ed979SColeman Kaneas it could create an integer overflow situation if the added 1107220ed979SColeman Kanelengths of a buffer and the unprocessed portion of the previous buffer 1108220ed979SColeman Kaneexceed the maximum integer value. Input data at the end of a buffer 1109220ed979SColeman Kanewill remain unprocessed if it is part of an XML token for which the 1110220ed979SColeman Kaneend is not part of that buffer.</p> 1111220ed979SColeman Kane 11124543ef51SXin LI<p><a name="isFinal"></a>The application <em>must</em> make a concluding 11134543ef51SXin LI<code><a href="#XML_Parse">XML_Parse</a></code> or 11144543ef51SXin LI<code><a href="#XML_ParseBuffer">XML_ParseBuffer</a></code> call 11154543ef51SXin LIwith <code>isFinal</code> set to <code>XML_TRUE</code>.</p> 11164543ef51SXin LI 1117cc68614dSXin LI<h4 id="XML_Parse">XML_Parse</h4> 1118cc68614dSXin LI<pre class="fcndec"> 1119220ed979SColeman Kaneenum XML_Status XMLCALL 11205bb6a25fSPoul-Henning KampXML_Parse(XML_Parser p, 11215bb6a25fSPoul-Henning Kamp const char *s, 11225bb6a25fSPoul-Henning Kamp int len, 11235bb6a25fSPoul-Henning Kamp int isFinal); 11245bb6a25fSPoul-Henning Kamp</pre> 11255bb6a25fSPoul-Henning Kamp<pre class="signature"> 11265bb6a25fSPoul-Henning Kampenum XML_Status { 11275bb6a25fSPoul-Henning Kamp XML_STATUS_ERROR = 0, 11285bb6a25fSPoul-Henning Kamp XML_STATUS_OK = 1 11295bb6a25fSPoul-Henning Kamp}; 11305bb6a25fSPoul-Henning Kamp</pre> 11315bb6a25fSPoul-Henning Kamp<div class="fcndef"> 11324543ef51SXin LI<p> 11335bb6a25fSPoul-Henning KampParse some more of the document. The string <code>s</code> is a buffer 11345bb6a25fSPoul-Henning Kampcontaining part (or perhaps all) of the document. The number of bytes of s 11355bb6a25fSPoul-Henning Kampthat are part of the document is indicated by <code>len</code>. This means 11364543ef51SXin LIthat <code>s</code> doesn't have to be null-terminated. It also means that 11375bb6a25fSPoul-Henning Kampif <code>len</code> is larger than the number of bytes in the block of 1138ffd294a1SEnji Coopermemory that <code>s</code> points at, then a memory fault is likely. 1139ffd294a1SEnji CooperNegative values for <code>len</code> are rejected since Expat 2.2.1. 1140ffd294a1SEnji CooperThe 11415bb6a25fSPoul-Henning Kamp<code>isFinal</code> parameter informs the parser that this is the last 11425bb6a25fSPoul-Henning Kamppiece of the document. Frequently, the last piece is empty (i.e. 11435bb6a25fSPoul-Henning Kamp<code>len</code> is zero.) 11444543ef51SXin LI</p> 11454543ef51SXin LI 11464543ef51SXin LI<p> 11475bb6a25fSPoul-Henning KampIf a parse error occurred, it returns <code>XML_STATUS_ERROR</code>. 11485bb6a25fSPoul-Henning KampOtherwise it returns <code>XML_STATUS_OK</code> value. 11494543ef51SXin LINote that regardless of the return value, there is no guarantee that all 11504543ef51SXin LIprovided input has been parsed; only after <a href="#isFinal">the 11514543ef51SXin LIconcluding call</a> will all handler callbacks and parsing errors have 11524543ef51SXin LIhappened. 11534543ef51SXin LI</p> 11544543ef51SXin LI 11554543ef51SXin LI<p> 11564543ef51SXin LISimplified, <code>XML_Parse</code> can be considered a convenience wrapper 11574543ef51SXin LIthat is pairing calls 11584543ef51SXin LIto <code><a href="#XML_GetBuffer">XML_GetBuffer</a></code> 11594543ef51SXin LIand <code><a href="#XML_ParseBuffer">XML_ParseBuffer</a></code> 11604543ef51SXin LI(when Expat is built with macro <code>XML_CONTEXT_BYTES</code> 11614543ef51SXin LIdefined to a positive value, which is both common and default). 11624543ef51SXin LI<code>XML_Parse</code> is then functionally equivalent to calling 11634543ef51SXin LI<code><a href="#XML_GetBuffer">XML_GetBuffer</a></code>, 11644543ef51SXin LI<code>memcpy</code>, and 11654543ef51SXin LI<code><a href="#XML_ParseBuffer">XML_ParseBuffer</a></code>. 11664543ef51SXin LI</p> 11674543ef51SXin LI 11684543ef51SXin LI<p> 11694543ef51SXin LITo avoid double copying of the input, direct use of functions 11704543ef51SXin LI<code><a href="#XML_GetBuffer">XML_GetBuffer</a></code> and 11714543ef51SXin LI<code><a href="#XML_ParseBuffer">XML_ParseBuffer</a></code> is advised 11724543ef51SXin LIfor most production use, e.g. 11734543ef51SXin LIif you're using <code>read</code> or similar functionality to fill your 11744543ef51SXin LIbuffers, fill directly into the buffer from 11754543ef51SXin LI<code><a href="#XML_GetBuffer">XML_GetBuffer</a></code>, 11764543ef51SXin LIthen parse with <code><a href="#XML_ParseBuffer">XML_ParseBuffer</a></code>. 11774543ef51SXin LI</p> 11785bb6a25fSPoul-Henning Kamp</div> 11795bb6a25fSPoul-Henning Kamp 1180cc68614dSXin LI<h4 id="XML_ParseBuffer">XML_ParseBuffer</h4> 1181cc68614dSXin LI<pre class="fcndec"> 1182220ed979SColeman Kaneenum XML_Status XMLCALL 11835bb6a25fSPoul-Henning KampXML_ParseBuffer(XML_Parser p, 11845bb6a25fSPoul-Henning Kamp int len, 11855bb6a25fSPoul-Henning Kamp int isFinal); 11865bb6a25fSPoul-Henning Kamp</pre> 11875bb6a25fSPoul-Henning Kamp<div class="fcndef"> 1188ffd294a1SEnji Cooper<p> 11895bb6a25fSPoul-Henning KampThis is just like <code><a href= "#XML_Parse" >XML_Parse</a></code>, 11905bb6a25fSPoul-Henning Kampexcept in this case Expat provides the buffer. By obtaining the 11915bb6a25fSPoul-Henning Kampbuffer from Expat with the <code><a href= "#XML_GetBuffer" 11925bb6a25fSPoul-Henning Kamp>XML_GetBuffer</a></code> function, the application can avoid double 11935bb6a25fSPoul-Henning Kampcopying of the input. 1194ffd294a1SEnji Cooper</p> 1195ffd294a1SEnji Cooper 1196ffd294a1SEnji Cooper<p> 1197ffd294a1SEnji CooperNegative values for <code>len</code> are rejected since Expat 2.6.3. 1198ffd294a1SEnji Cooper</p> 11995bb6a25fSPoul-Henning Kamp</div> 12005bb6a25fSPoul-Henning Kamp 1201cc68614dSXin LI<h4 id="XML_GetBuffer">XML_GetBuffer</h4> 1202cc68614dSXin LI<pre class="fcndec"> 1203220ed979SColeman Kanevoid * XMLCALL 12045bb6a25fSPoul-Henning KampXML_GetBuffer(XML_Parser p, 12055bb6a25fSPoul-Henning Kamp int len); 12065bb6a25fSPoul-Henning Kamp</pre> 12075bb6a25fSPoul-Henning Kamp<div class="fcndef"> 12085bb6a25fSPoul-Henning KampObtain a buffer of size <code>len</code> to read a piece of the document 12094543ef51SXin LIinto. A <code>NULL</code> value is returned if Expat can't allocate enough memory for 12104543ef51SXin LIthis buffer. A <code>NULL</code> value may also be returned if <code>len</code> is zero. 1211cc68614dSXin LIThis has to be called prior to every call to 12125bb6a25fSPoul-Henning Kamp<code><a href= "#XML_ParseBuffer" >XML_ParseBuffer</a></code>. A 12135bb6a25fSPoul-Henning Kamptypical use would look like this: 12145bb6a25fSPoul-Henning Kamp 12155bb6a25fSPoul-Henning Kamp<pre class="eg"> 12165bb6a25fSPoul-Henning Kampfor (;;) { 12175bb6a25fSPoul-Henning Kamp int bytes_read; 12185bb6a25fSPoul-Henning Kamp void *buff = XML_GetBuffer(p, BUFF_SIZE); 12195bb6a25fSPoul-Henning Kamp if (buff == NULL) { 12205bb6a25fSPoul-Henning Kamp /* handle error */ 12215bb6a25fSPoul-Henning Kamp } 12225bb6a25fSPoul-Henning Kamp 12235bb6a25fSPoul-Henning Kamp bytes_read = read(docfd, buff, BUFF_SIZE); 12245bb6a25fSPoul-Henning Kamp if (bytes_read < 0) { 12255bb6a25fSPoul-Henning Kamp /* handle error */ 12265bb6a25fSPoul-Henning Kamp } 12275bb6a25fSPoul-Henning Kamp 12285bb6a25fSPoul-Henning Kamp if (! XML_ParseBuffer(p, bytes_read, bytes_read == 0)) { 12295bb6a25fSPoul-Henning Kamp /* handle parse error */ 12305bb6a25fSPoul-Henning Kamp } 12315bb6a25fSPoul-Henning Kamp 12325bb6a25fSPoul-Henning Kamp if (bytes_read == 0) 12335bb6a25fSPoul-Henning Kamp break; 12345bb6a25fSPoul-Henning Kamp} 12355bb6a25fSPoul-Henning Kamp</pre> 12365bb6a25fSPoul-Henning Kamp</div> 12375bb6a25fSPoul-Henning Kamp 1238cc68614dSXin LI<h4 id="XML_StopParser">XML_StopParser</h4> 1239cc68614dSXin LI<pre class="fcndec"> 1240220ed979SColeman Kaneenum XML_Status XMLCALL 1241220ed979SColeman KaneXML_StopParser(XML_Parser p, 1242220ed979SColeman Kane XML_Bool resumable); 1243220ed979SColeman Kane</pre> 1244220ed979SColeman Kane<div class="fcndef"> 1245220ed979SColeman Kane 1246220ed979SColeman Kane<p>Stops parsing, causing <code><a href= "#XML_Parse" 1247220ed979SColeman Kane>XML_Parse</a></code> or <code><a href= "#XML_ParseBuffer" 1248220ed979SColeman Kane>XML_ParseBuffer</a></code> to return. Must be called from within a 1249220ed979SColeman Kanecall-back handler, except when aborting (when <code>resumable</code> 1250220ed979SColeman Kaneis <code>XML_FALSE</code>) an already suspended parser. Some 1251220ed979SColeman Kanecall-backs may still follow because they would otherwise get 1252cc68614dSXin LIlost, including</p> 1253220ed979SColeman Kane<ul> 1254220ed979SColeman Kane <li> the end element handler for empty elements when stopped in the 1255220ed979SColeman Kane start element handler,</li> 1256220ed979SColeman Kane <li> the end namespace declaration handler when stopped in the end 1257220ed979SColeman Kane element handler,</li> 1258220ed979SColeman Kane <li> the character data handler when stopped in the character data handler 1259220ed979SColeman Kane while making multiple call-backs on a contiguous chunk of characters,</li> 1260220ed979SColeman Kane</ul> 1261cc68614dSXin LI<p>and possibly others.</p> 1262220ed979SColeman Kane 1263220ed979SColeman Kane<p>This can be called from most handlers, including DTD related 1264220ed979SColeman Kanecall-backs, except when parsing an external parameter entity and 1265220ed979SColeman Kane<code>resumable</code> is <code>XML_TRUE</code>. Returns 1266220ed979SColeman Kane<code>XML_STATUS_OK</code> when successful, 1267220ed979SColeman Kane<code>XML_STATUS_ERROR</code> otherwise. The possible error codes 1268220ed979SColeman Kaneare:</p> 1269220ed979SColeman Kane<dl> 1270220ed979SColeman Kane <dt><code>XML_ERROR_SUSPENDED</code></dt> 1271220ed979SColeman Kane <dd>when suspending an already suspended parser.</dd> 1272220ed979SColeman Kane <dt><code>XML_ERROR_FINISHED</code></dt> 1273220ed979SColeman Kane <dd>when the parser has already finished.</dd> 1274220ed979SColeman Kane <dt><code>XML_ERROR_SUSPEND_PE</code></dt> 1275220ed979SColeman Kane <dd>when suspending while parsing an external PE.</dd> 1276220ed979SColeman Kane</dl> 1277220ed979SColeman Kane 1278220ed979SColeman Kane<p>Since the stop/resume feature requires application support in the 1279220ed979SColeman Kaneouter parsing loop, it is an error to call this function for a parser 1280220ed979SColeman Kanenot being handled appropriately; see <a href= "#stop-resume" 1281220ed979SColeman Kane>Temporarily Stopping Parsing</a> for more information.</p> 1282220ed979SColeman Kane 1283220ed979SColeman Kane<p>When <code>resumable</code> is <code>XML_TRUE</code> then parsing 1284220ed979SColeman Kaneis <em>suspended</em>, that is, <code><a href= "#XML_Parse" 1285220ed979SColeman Kane>XML_Parse</a></code> and <code><a href= "#XML_ParseBuffer" 1286220ed979SColeman Kane>XML_ParseBuffer</a></code> return <code>XML_STATUS_SUSPENDED</code>. 1287220ed979SColeman KaneOtherwise, parsing is <em>aborted</em>, that is, <code><a href= 1288220ed979SColeman Kane"#XML_Parse" >XML_Parse</a></code> and <code><a href= 1289220ed979SColeman Kane"#XML_ParseBuffer" >XML_ParseBuffer</a></code> return 1290220ed979SColeman Kane<code>XML_STATUS_ERROR</code> with error code 1291220ed979SColeman Kane<code>XML_ERROR_ABORTED</code>.</p> 1292220ed979SColeman Kane 1293220ed979SColeman Kane<p><strong>Note:</strong> 1294220ed979SColeman KaneThis will be applied to the current parser instance only, that is, if 1295220ed979SColeman Kanethere is a parent parser then it will continue parsing when the 1296220ed979SColeman Kaneexternal entity reference handler returns. It is up to the 1297220ed979SColeman Kaneimplementation of that handler to call <code><a href= 1298220ed979SColeman Kane"#XML_StopParser" >XML_StopParser</a></code> on the parent parser 1299220ed979SColeman Kane(recursively), if one wants to stop parsing altogether.</p> 1300220ed979SColeman Kane 1301220ed979SColeman Kane<p>When suspended, parsing can be resumed by calling <code><a href= 1302220ed979SColeman Kane"#XML_ResumeParser" >XML_ResumeParser</a></code>.</p> 1303220ed979SColeman Kane 1304220ed979SColeman Kane<p>New in Expat 1.95.8.</p> 1305220ed979SColeman Kane</div> 1306220ed979SColeman Kane 1307cc68614dSXin LI<h4 id="XML_ResumeParser">XML_ResumeParser</h4> 1308cc68614dSXin LI<pre class="fcndec"> 1309220ed979SColeman Kaneenum XML_Status XMLCALL 1310220ed979SColeman KaneXML_ResumeParser(XML_Parser p); 1311220ed979SColeman Kane</pre> 1312220ed979SColeman Kane<div class="fcndef"> 1313220ed979SColeman Kane<p>Resumes parsing after it has been suspended with <code><a href= 1314220ed979SColeman Kane"#XML_StopParser" >XML_StopParser</a></code>. Must not be called from 1315220ed979SColeman Kanewithin a handler call-back. Returns same status codes as <code><a 1316220ed979SColeman Kanehref= "#XML_Parse">XML_Parse</a></code> or <code><a href= 1317220ed979SColeman Kane"#XML_ParseBuffer" >XML_ParseBuffer</a></code>. An additional error 1318220ed979SColeman Kanecode, <code>XML_ERROR_NOT_SUSPENDED</code>, will be returned if the 1319220ed979SColeman Kaneparser was not currently suspended.</p> 1320220ed979SColeman Kane 1321220ed979SColeman Kane<p><strong>Note:</strong> 1322220ed979SColeman KaneThis must be called on the most deeply nested child parser instance 1323220ed979SColeman Kanefirst, and on its parent parser only after the child parser has 1324220ed979SColeman Kanefinished, to be applied recursively until the document entity's parser 1325220ed979SColeman Kaneis restarted. That is, the parent parser will not resume by itself 1326220ed979SColeman Kaneand it is up to the application to call <code><a href= 1327220ed979SColeman Kane"#XML_ResumeParser" >XML_ResumeParser</a></code> on it at the 1328220ed979SColeman Kaneappropriate moment.</p> 1329220ed979SColeman Kane 1330220ed979SColeman Kane<p>New in Expat 1.95.8.</p> 1331220ed979SColeman Kane</div> 1332220ed979SColeman Kane 1333cc68614dSXin LI<h4 id="XML_GetParsingStatus">XML_GetParsingStatus</h4> 1334cc68614dSXin LI<pre class="fcndec"> 1335220ed979SColeman Kanevoid XMLCALL 1336220ed979SColeman KaneXML_GetParsingStatus(XML_Parser p, 1337220ed979SColeman Kane XML_ParsingStatus *status); 1338220ed979SColeman Kane</pre> 1339220ed979SColeman Kane<pre class="signature"> 1340220ed979SColeman Kaneenum XML_Parsing { 1341220ed979SColeman Kane XML_INITIALIZED, 1342220ed979SColeman Kane XML_PARSING, 1343220ed979SColeman Kane XML_FINISHED, 1344220ed979SColeman Kane XML_SUSPENDED 1345220ed979SColeman Kane}; 1346220ed979SColeman Kane 1347220ed979SColeman Kanetypedef struct { 1348220ed979SColeman Kane enum XML_Parsing parsing; 1349220ed979SColeman Kane XML_Bool finalBuffer; 1350220ed979SColeman Kane} XML_ParsingStatus; 1351220ed979SColeman Kane</pre> 1352220ed979SColeman Kane<div class="fcndef"> 1353220ed979SColeman Kane<p>Returns status of parser with respect to being initialized, 1354220ed979SColeman Kaneparsing, finished, or suspended, and whether the final buffer is being 1355220ed979SColeman Kaneprocessed. The <code>status</code> parameter <em>must not</em> be 13564543ef51SXin LI<code>NULL</code>.</p> 1357220ed979SColeman Kane 1358220ed979SColeman Kane<p>New in Expat 1.95.8.</p> 1359220ed979SColeman Kane</div> 1360220ed979SColeman Kane 1361220ed979SColeman Kane 13625bb6a25fSPoul-Henning Kamp<h3><a name="setting">Handler Setting</a></h3> 13635bb6a25fSPoul-Henning Kamp 13645bb6a25fSPoul-Henning Kamp<p>Although handlers are typically set prior to parsing and left alone, an 13655bb6a25fSPoul-Henning Kampapplication may choose to set or change the handler for a parsing event 13665bb6a25fSPoul-Henning Kampwhile the parse is in progress. For instance, your application may choose 13675bb6a25fSPoul-Henning Kampto ignore all text not descended from a <code>para</code> element. One 13685bb6a25fSPoul-Henning Kampway it could do this is to set the character handler when a para start tag 13695bb6a25fSPoul-Henning Kampis seen, and unset it for the corresponding end tag.</p> 13705bb6a25fSPoul-Henning Kamp 13714543ef51SXin LI<p>A handler may be <em>unset</em> by providing a <code>NULL</code> pointer to the 13725bb6a25fSPoul-Henning Kampappropriate handler setter. None of the handler setting functions have 13735bb6a25fSPoul-Henning Kampa return value.</p> 13745bb6a25fSPoul-Henning Kamp 13755bb6a25fSPoul-Henning Kamp<p>Your handlers will be receiving strings in arrays of type 1376220ed979SColeman Kane<code>XML_Char</code>. This type is conditionally defined in expat.h as 1377220ed979SColeman Kaneeither <code>char</code>, <code>wchar_t</code> or <code>unsigned short</code>. 1378220ed979SColeman KaneThe former implies UTF-8 encoding, the latter two imply UTF-16 encoding. 1379220ed979SColeman KaneNote that you'll receive them in this form independent of the original 1380220ed979SColeman Kaneencoding of the document.</p> 13815bb6a25fSPoul-Henning Kamp 13825bb6a25fSPoul-Henning Kamp<div class="handler"> 1383cc68614dSXin LI<h4 id="XML_SetStartElementHandler">XML_SetStartElementHandler</h4> 1384cc68614dSXin LI<pre class="setter"> 1385220ed979SColeman Kanevoid XMLCALL 13865bb6a25fSPoul-Henning KampXML_SetStartElementHandler(XML_Parser p, 13875bb6a25fSPoul-Henning Kamp XML_StartElementHandler start); 13885bb6a25fSPoul-Henning Kamp</pre> 13895bb6a25fSPoul-Henning Kamp<pre class="signature"> 13905bb6a25fSPoul-Henning Kamptypedef void 1391220ed979SColeman Kane(XMLCALL *XML_StartElementHandler)(void *userData, 13925bb6a25fSPoul-Henning Kamp const XML_Char *name, 13935bb6a25fSPoul-Henning Kamp const XML_Char **atts); 13945bb6a25fSPoul-Henning Kamp</pre> 13955bb6a25fSPoul-Henning Kamp<p>Set handler for start (and empty) tags. Attributes are passed to the start 13965bb6a25fSPoul-Henning Kamphandler as a pointer to a vector of char pointers. Each attribute seen in 13975bb6a25fSPoul-Henning Kampa start (or empty) tag occupies 2 consecutive places in this vector: the 13985bb6a25fSPoul-Henning Kampattribute name followed by the attribute value. These pairs are terminated 13994543ef51SXin LIby a <code>NULL</code> pointer.</p> 14005bb6a25fSPoul-Henning Kamp<p>Note that an empty tag generates a call to both start and end handlers 14015bb6a25fSPoul-Henning Kamp(in that order).</p> 14025bb6a25fSPoul-Henning Kamp</div> 14035bb6a25fSPoul-Henning Kamp 14045bb6a25fSPoul-Henning Kamp<div class="handler"> 1405cc68614dSXin LI<h4 id="XML_SetEndElementHandler">XML_SetEndElementHandler</h4> 1406cc68614dSXin LI<pre class="setter"> 1407220ed979SColeman Kanevoid XMLCALL 14085bb6a25fSPoul-Henning KampXML_SetEndElementHandler(XML_Parser p, 14095bb6a25fSPoul-Henning Kamp XML_EndElementHandler); 14105bb6a25fSPoul-Henning Kamp</pre> 14115bb6a25fSPoul-Henning Kamp<pre class="signature"> 14125bb6a25fSPoul-Henning Kamptypedef void 1413220ed979SColeman Kane(XMLCALL *XML_EndElementHandler)(void *userData, 14145bb6a25fSPoul-Henning Kamp const XML_Char *name); 14155bb6a25fSPoul-Henning Kamp</pre> 14165bb6a25fSPoul-Henning Kamp<p>Set handler for end (and empty) tags. As noted above, an empty tag 14175bb6a25fSPoul-Henning Kampgenerates a call to both start and end handlers.</p> 14185bb6a25fSPoul-Henning Kamp</div> 14195bb6a25fSPoul-Henning Kamp 14205bb6a25fSPoul-Henning Kamp<div class="handler"> 1421cc68614dSXin LI<h4 id="XML_SetElementHandler">XML_SetElementHandler</h4> 1422cc68614dSXin LI<pre class="setter"> 1423220ed979SColeman Kanevoid XMLCALL 14245bb6a25fSPoul-Henning KampXML_SetElementHandler(XML_Parser p, 14255bb6a25fSPoul-Henning Kamp XML_StartElementHandler start, 14265bb6a25fSPoul-Henning Kamp XML_EndElementHandler end); 14275bb6a25fSPoul-Henning Kamp</pre> 14285bb6a25fSPoul-Henning Kamp<p>Set handlers for start and end tags with one call.</p> 14295bb6a25fSPoul-Henning Kamp</div> 14305bb6a25fSPoul-Henning Kamp 14315bb6a25fSPoul-Henning Kamp<div class="handler"> 1432cc68614dSXin LI<h4 id="XML_SetCharacterDataHandler">XML_SetCharacterDataHandler</h4> 1433cc68614dSXin LI<pre class="setter"> 1434220ed979SColeman Kanevoid XMLCALL 14355bb6a25fSPoul-Henning KampXML_SetCharacterDataHandler(XML_Parser p, 14365bb6a25fSPoul-Henning Kamp XML_CharacterDataHandler charhndl) 14375bb6a25fSPoul-Henning Kamp</pre> 14385bb6a25fSPoul-Henning Kamp<pre class="signature"> 14395bb6a25fSPoul-Henning Kamptypedef void 1440220ed979SColeman Kane(XMLCALL *XML_CharacterDataHandler)(void *userData, 14415bb6a25fSPoul-Henning Kamp const XML_Char *s, 14425bb6a25fSPoul-Henning Kamp int len); 14435bb6a25fSPoul-Henning Kamp</pre> 14445bb6a25fSPoul-Henning Kamp<p>Set a text handler. The string your handler receives 1445cc68614dSXin LIis <em>NOT null-terminated</em>. You have to use the length argument 14465bb6a25fSPoul-Henning Kampto deal with the end of the string. A single block of contiguous text 14475bb6a25fSPoul-Henning Kampfree of markup may still result in a sequence of calls to this handler. 14485bb6a25fSPoul-Henning KampIn other words, if you're searching for a pattern in the text, it may 14494543ef51SXin LIbe split across calls to this handler. Note: Setting this handler to <code>NULL</code> 1450220ed979SColeman Kanemay <em>NOT immediately</em> terminate call-backs if the parser is currently 1451220ed979SColeman Kaneprocessing such a single block of contiguous markup-free text, as the parser 1452220ed979SColeman Kanewill continue calling back until the end of the block is reached.</p> 14535bb6a25fSPoul-Henning Kamp</div> 14545bb6a25fSPoul-Henning Kamp 14555bb6a25fSPoul-Henning Kamp<div class="handler"> 1456cc68614dSXin LI<h4 id="XML_SetProcessingInstructionHandler">XML_SetProcessingInstructionHandler</h4> 1457cc68614dSXin LI<pre class="setter"> 1458220ed979SColeman Kanevoid XMLCALL 14595bb6a25fSPoul-Henning KampXML_SetProcessingInstructionHandler(XML_Parser p, 14605bb6a25fSPoul-Henning Kamp XML_ProcessingInstructionHandler proc) 14615bb6a25fSPoul-Henning Kamp</pre> 14625bb6a25fSPoul-Henning Kamp<pre class="signature"> 14635bb6a25fSPoul-Henning Kamptypedef void 1464220ed979SColeman Kane(XMLCALL *XML_ProcessingInstructionHandler)(void *userData, 14655bb6a25fSPoul-Henning Kamp const XML_Char *target, 14665bb6a25fSPoul-Henning Kamp const XML_Char *data); 14675bb6a25fSPoul-Henning Kamp 14685bb6a25fSPoul-Henning Kamp</pre> 14695bb6a25fSPoul-Henning Kamp<p>Set a handler for processing instructions. The target is the first word 14705bb6a25fSPoul-Henning Kampin the processing instruction. The data is the rest of the characters in 14715bb6a25fSPoul-Henning Kampit after skipping all whitespace after the initial word.</p> 14725bb6a25fSPoul-Henning Kamp</div> 14735bb6a25fSPoul-Henning Kamp 14745bb6a25fSPoul-Henning Kamp<div class="handler"> 1475cc68614dSXin LI<h4 id="XML_SetCommentHandler">XML_SetCommentHandler</h4> 1476cc68614dSXin LI<pre class="setter"> 1477220ed979SColeman Kanevoid XMLCALL 14785bb6a25fSPoul-Henning KampXML_SetCommentHandler(XML_Parser p, 14795bb6a25fSPoul-Henning Kamp XML_CommentHandler cmnt) 14805bb6a25fSPoul-Henning Kamp</pre> 14815bb6a25fSPoul-Henning Kamp<pre class="signature"> 14825bb6a25fSPoul-Henning Kamptypedef void 1483220ed979SColeman Kane(XMLCALL *XML_CommentHandler)(void *userData, 14845bb6a25fSPoul-Henning Kamp const XML_Char *data); 14855bb6a25fSPoul-Henning Kamp</pre> 14865bb6a25fSPoul-Henning Kamp<p>Set a handler for comments. The data is all text inside the comment 14875bb6a25fSPoul-Henning Kampdelimiters.</p> 14885bb6a25fSPoul-Henning Kamp</div> 14895bb6a25fSPoul-Henning Kamp 14905bb6a25fSPoul-Henning Kamp<div class="handler"> 1491cc68614dSXin LI<h4 id="XML_SetStartCdataSectionHandler">XML_SetStartCdataSectionHandler</h4> 1492cc68614dSXin LI<pre class="setter"> 1493220ed979SColeman Kanevoid XMLCALL 14945bb6a25fSPoul-Henning KampXML_SetStartCdataSectionHandler(XML_Parser p, 14955bb6a25fSPoul-Henning Kamp XML_StartCdataSectionHandler start); 14965bb6a25fSPoul-Henning Kamp</pre> 14975bb6a25fSPoul-Henning Kamp<pre class="signature"> 14985bb6a25fSPoul-Henning Kamptypedef void 1499220ed979SColeman Kane(XMLCALL *XML_StartCdataSectionHandler)(void *userData); 15005bb6a25fSPoul-Henning Kamp</pre> 15015bb6a25fSPoul-Henning Kamp<p>Set a handler that gets called at the beginning of a CDATA section.</p> 15025bb6a25fSPoul-Henning Kamp</div> 15035bb6a25fSPoul-Henning Kamp 15045bb6a25fSPoul-Henning Kamp<div class="handler"> 1505cc68614dSXin LI<h4 id="XML_SetEndCdataSectionHandler">XML_SetEndCdataSectionHandler</h4> 1506cc68614dSXin LI<pre class="setter"> 1507220ed979SColeman Kanevoid XMLCALL 15085bb6a25fSPoul-Henning KampXML_SetEndCdataSectionHandler(XML_Parser p, 15095bb6a25fSPoul-Henning Kamp XML_EndCdataSectionHandler end); 15105bb6a25fSPoul-Henning Kamp</pre> 15115bb6a25fSPoul-Henning Kamp<pre class="signature"> 15125bb6a25fSPoul-Henning Kamptypedef void 1513220ed979SColeman Kane(XMLCALL *XML_EndCdataSectionHandler)(void *userData); 15145bb6a25fSPoul-Henning Kamp</pre> 15155bb6a25fSPoul-Henning Kamp<p>Set a handler that gets called at the end of a CDATA section.</p> 15165bb6a25fSPoul-Henning Kamp</div> 15175bb6a25fSPoul-Henning Kamp 15185bb6a25fSPoul-Henning Kamp<div class="handler"> 1519cc68614dSXin LI<h4 id="XML_SetCdataSectionHandler">XML_SetCdataSectionHandler</h4> 1520cc68614dSXin LI<pre class="setter"> 1521220ed979SColeman Kanevoid XMLCALL 15225bb6a25fSPoul-Henning KampXML_SetCdataSectionHandler(XML_Parser p, 15235bb6a25fSPoul-Henning Kamp XML_StartCdataSectionHandler start, 15245bb6a25fSPoul-Henning Kamp XML_EndCdataSectionHandler end) 15255bb6a25fSPoul-Henning Kamp</pre> 15265bb6a25fSPoul-Henning Kamp<p>Sets both CDATA section handlers with one call.</p> 15275bb6a25fSPoul-Henning Kamp</div> 15285bb6a25fSPoul-Henning Kamp 15295bb6a25fSPoul-Henning Kamp<div class="handler"> 1530cc68614dSXin LI<h4 id="XML_SetDefaultHandler">XML_SetDefaultHandler</h4> 1531cc68614dSXin LI<pre class="setter"> 1532220ed979SColeman Kanevoid XMLCALL 15335bb6a25fSPoul-Henning KampXML_SetDefaultHandler(XML_Parser p, 15345bb6a25fSPoul-Henning Kamp XML_DefaultHandler hndl) 15355bb6a25fSPoul-Henning Kamp</pre> 15365bb6a25fSPoul-Henning Kamp<pre class="signature"> 15375bb6a25fSPoul-Henning Kamptypedef void 1538220ed979SColeman Kane(XMLCALL *XML_DefaultHandler)(void *userData, 15395bb6a25fSPoul-Henning Kamp const XML_Char *s, 15405bb6a25fSPoul-Henning Kamp int len); 15415bb6a25fSPoul-Henning Kamp</pre> 15425bb6a25fSPoul-Henning Kamp 15435bb6a25fSPoul-Henning Kamp<p>Sets a handler for any characters in the document which wouldn't 15445bb6a25fSPoul-Henning Kampotherwise be handled. This includes both data for which no handlers 15455bb6a25fSPoul-Henning Kampcan be set (like some kinds of DTD declarations) and data which could 15465bb6a25fSPoul-Henning Kampbe reported but which currently has no handler set. The characters 15475bb6a25fSPoul-Henning Kampare passed exactly as they were present in the XML document except 15485bb6a25fSPoul-Henning Kampthat they will be encoded in UTF-8 or UTF-16. Line boundaries are not 15495bb6a25fSPoul-Henning Kampnormalized. Note that a byte order mark character is not passed to the 15505bb6a25fSPoul-Henning Kampdefault handler. There are no guarantees about how characters are 15515bb6a25fSPoul-Henning Kampdivided between calls to the default handler: for example, a comment 15525bb6a25fSPoul-Henning Kampmight be split between multiple calls. Setting the handler with 15535bb6a25fSPoul-Henning Kampthis call has the side effect of turning off expansion of references 15545bb6a25fSPoul-Henning Kampto internally defined general entities. Instead these references are 15555bb6a25fSPoul-Henning Kamppassed to the default handler.</p> 15565bb6a25fSPoul-Henning Kamp 15575bb6a25fSPoul-Henning Kamp<p>See also <code><a 15585bb6a25fSPoul-Henning Kamphref="#XML_DefaultCurrent">XML_DefaultCurrent</a></code>.</p> 15595bb6a25fSPoul-Henning Kamp</div> 15605bb6a25fSPoul-Henning Kamp 15615bb6a25fSPoul-Henning Kamp<div class="handler"> 1562cc68614dSXin LI<h4 id="XML_SetDefaultHandlerExpand">XML_SetDefaultHandlerExpand</h4> 1563cc68614dSXin LI<pre class="setter"> 1564220ed979SColeman Kanevoid XMLCALL 15655bb6a25fSPoul-Henning KampXML_SetDefaultHandlerExpand(XML_Parser p, 15665bb6a25fSPoul-Henning Kamp XML_DefaultHandler hndl) 15675bb6a25fSPoul-Henning Kamp</pre> 15685bb6a25fSPoul-Henning Kamp<pre class="signature"> 15695bb6a25fSPoul-Henning Kamptypedef void 1570220ed979SColeman Kane(XMLCALL *XML_DefaultHandler)(void *userData, 15715bb6a25fSPoul-Henning Kamp const XML_Char *s, 15725bb6a25fSPoul-Henning Kamp int len); 15735bb6a25fSPoul-Henning Kamp</pre> 15745bb6a25fSPoul-Henning Kamp<p>This sets a default handler, but doesn't inhibit the expansion of 15755bb6a25fSPoul-Henning Kampinternal entity references. The entity reference will not be passed 15765bb6a25fSPoul-Henning Kampto the default handler.</p> 15775bb6a25fSPoul-Henning Kamp 15785bb6a25fSPoul-Henning Kamp<p>See also <code><a 15795bb6a25fSPoul-Henning Kamphref="#XML_DefaultCurrent">XML_DefaultCurrent</a></code>.</p> 15805bb6a25fSPoul-Henning Kamp</div> 15815bb6a25fSPoul-Henning Kamp 15825bb6a25fSPoul-Henning Kamp<div class="handler"> 1583cc68614dSXin LI<h4 id="XML_SetExternalEntityRefHandler">XML_SetExternalEntityRefHandler</h4> 1584cc68614dSXin LI<pre class="setter"> 1585220ed979SColeman Kanevoid XMLCALL 15865bb6a25fSPoul-Henning KampXML_SetExternalEntityRefHandler(XML_Parser p, 15875bb6a25fSPoul-Henning Kamp XML_ExternalEntityRefHandler hndl) 15885bb6a25fSPoul-Henning Kamp</pre> 15895bb6a25fSPoul-Henning Kamp<pre class="signature"> 15905bb6a25fSPoul-Henning Kamptypedef int 1591220ed979SColeman Kane(XMLCALL *XML_ExternalEntityRefHandler)(XML_Parser p, 15925bb6a25fSPoul-Henning Kamp const XML_Char *context, 15935bb6a25fSPoul-Henning Kamp const XML_Char *base, 15945bb6a25fSPoul-Henning Kamp const XML_Char *systemId, 15955bb6a25fSPoul-Henning Kamp const XML_Char *publicId); 15965bb6a25fSPoul-Henning Kamp</pre> 15975bb6a25fSPoul-Henning Kamp<p>Set an external entity reference handler. This handler is also 15985bb6a25fSPoul-Henning Kampcalled for processing an external DTD subset if parameter entity parsing 15995bb6a25fSPoul-Henning Kampis in effect. (See <a href="#XML_SetParamEntityParsing"> 16005bb6a25fSPoul-Henning Kamp<code>XML_SetParamEntityParsing</code></a>.)</p> 16015bb6a25fSPoul-Henning Kamp 1602220ed979SColeman Kane<p>The <code>context</code> parameter specifies the parsing context in 1603220ed979SColeman Kanethe format expected by the <code>context</code> argument to <code><a 1604220ed979SColeman Kanehref="#XML_ExternalEntityParserCreate" 1605220ed979SColeman Kane>XML_ExternalEntityParserCreate</a></code>. <code>code</code> is 1606220ed979SColeman Kanevalid only until the handler returns, so if the referenced entity is 16074543ef51SXin LIto be parsed later, it must be copied. <code>context</code> is <code>NULL</code> 1608220ed979SColeman Kaneonly when the entity is a parameter entity, which is how one can 1609220ed979SColeman Kanedifferentiate between general and parameter entities.</p> 16105bb6a25fSPoul-Henning Kamp 1611220ed979SColeman Kane<p>The <code>base</code> parameter is the base to use for relative 1612220ed979SColeman Kanesystem identifiers. It is set by <code><a 16134543ef51SXin LIhref="#XML_SetBase">XML_SetBase</a></code> and may be <code>NULL</code>. The 1614220ed979SColeman Kane<code>publicId</code> parameter is the public id given in the entity 16154543ef51SXin LIdeclaration and may be <code>NULL</code>. <code>systemId</code> is the system 16164543ef51SXin LIidentifier specified in the entity declaration and is never <code>NULL</code>.</p> 16175bb6a25fSPoul-Henning Kamp 1618220ed979SColeman Kane<p>There are a couple of ways in which this handler differs from 1619220ed979SColeman Kaneothers. First, this handler returns a status indicator (an 1620220ed979SColeman Kaneinteger). <code>XML_STATUS_OK</code> should be returned for successful 1621220ed979SColeman Kanehandling of the external entity reference. Returning 1622220ed979SColeman Kane<code>XML_STATUS_ERROR</code> indicates failure, and causes the 1623220ed979SColeman Kanecalling parser to return an 1624220ed979SColeman Kane<code>XML_ERROR_EXTERNAL_ENTITY_HANDLING</code> error.</p> 16255bb6a25fSPoul-Henning Kamp 1626220ed979SColeman Kane<p>Second, instead of having the user data as its first argument, it 1627220ed979SColeman Kanereceives the parser that encountered the entity reference. This, along 1628220ed979SColeman Kanewith the context parameter, may be used as arguments to a call to 1629220ed979SColeman Kane<code><a href= "#XML_ExternalEntityParserCreate" 1630220ed979SColeman Kane>XML_ExternalEntityParserCreate</a></code>. Using the returned 1631220ed979SColeman Kaneparser, the body of the external entity can be recursively parsed.</p> 16325bb6a25fSPoul-Henning Kamp 16335bb6a25fSPoul-Henning Kamp<p>Since this handler may be called recursively, it should not be saving 16345bb6a25fSPoul-Henning Kampinformation into global or static variables.</p> 16355bb6a25fSPoul-Henning Kamp</div> 16365bb6a25fSPoul-Henning Kamp 1637cc68614dSXin LI<h4 id="XML_SetExternalEntityRefHandlerArg">XML_SetExternalEntityRefHandlerArg</h4> 1638cc68614dSXin LI<pre class="fcndec"> 1639220ed979SColeman Kanevoid XMLCALL 1640220ed979SColeman KaneXML_SetExternalEntityRefHandlerArg(XML_Parser p, 1641220ed979SColeman Kane void *arg) 1642220ed979SColeman Kane</pre> 1643220ed979SColeman Kane<div class="fcndef"> 1644220ed979SColeman Kane<p>Set the argument passed to the ExternalEntityRefHandler. If 16454543ef51SXin LI<code>arg</code> is not <code>NULL</code>, it is the new value passed to the 1646220ed979SColeman Kanehandler set using <code><a href="#XML_SetExternalEntityRefHandler" 1647220ed979SColeman Kane>XML_SetExternalEntityRefHandler</a></code>; if <code>arg</code> is 16484543ef51SXin LI<code>NULL</code>, the argument passed to the handler function will be the parser 1649220ed979SColeman Kaneobject itself.</p> 1650220ed979SColeman Kane 1651220ed979SColeman Kane<p><strong>Note:</strong> 1652220ed979SColeman KaneThe type of <code>arg</code> and the type of the first argument to the 1653220ed979SColeman KaneExternalEntityRefHandler do not match. This function takes a 1654220ed979SColeman Kane<code>void *</code> to be passed to the handler, while the handler 1655220ed979SColeman Kaneaccepts an <code>XML_Parser</code>. This is a historical accident, 1656220ed979SColeman Kanebut will not be corrected before Expat 2.0 (at the earliest) to avoid 1657220ed979SColeman Kanecausing compiler warnings for code that's known to work with this 1658220ed979SColeman KaneAPI. It is the responsibility of the application code to know the 1659220ed979SColeman Kaneactual type of the argument passed to the handler and to manage it 1660220ed979SColeman Kaneproperly.</p> 1661220ed979SColeman Kane</div> 1662220ed979SColeman Kane 16635bb6a25fSPoul-Henning Kamp<div class="handler"> 1664cc68614dSXin LI<h4 id="XML_SetSkippedEntityHandler">XML_SetSkippedEntityHandler</h4> 1665cc68614dSXin LI<pre class="setter"> 1666220ed979SColeman Kanevoid XMLCALL 16675bb6a25fSPoul-Henning KampXML_SetSkippedEntityHandler(XML_Parser p, 16685bb6a25fSPoul-Henning Kamp XML_SkippedEntityHandler handler) 16695bb6a25fSPoul-Henning Kamp</pre> 16705bb6a25fSPoul-Henning Kamp<pre class="signature"> 16715bb6a25fSPoul-Henning Kamptypedef void 1672220ed979SColeman Kane(XMLCALL *XML_SkippedEntityHandler)(void *userData, 16735bb6a25fSPoul-Henning Kamp const XML_Char *entityName, 16745bb6a25fSPoul-Henning Kamp int is_parameter_entity); 16755bb6a25fSPoul-Henning Kamp</pre> 16765bb6a25fSPoul-Henning Kamp<p>Set a skipped entity handler. This is called in two situations:</p> 16775bb6a25fSPoul-Henning Kamp<ol> 16785bb6a25fSPoul-Henning Kamp <li>An entity reference is encountered for which no declaration 16795bb6a25fSPoul-Henning Kamp has been read <em>and</em> this is not an error.</li> 16805bb6a25fSPoul-Henning Kamp <li>An internal entity reference is read, but not expanded, because 16815bb6a25fSPoul-Henning Kamp <a href="#XML_SetDefaultHandler"><code>XML_SetDefaultHandler</code></a> 16825bb6a25fSPoul-Henning Kamp has been called.</li> 16835bb6a25fSPoul-Henning Kamp</ol> 16845bb6a25fSPoul-Henning Kamp<p>The <code>is_parameter_entity</code> argument will be non-zero for 1685cc68614dSXin LIa parameter entity and zero for a general entity.</p> <p>Note: Skipped 16865bb6a25fSPoul-Henning Kampparameter entities in declarations and skipped general entities in 16875bb6a25fSPoul-Henning Kampattribute values cannot be reported, because the event would be out of 16885bb6a25fSPoul-Henning Kampsync with the reporting of the declarations or attribute values</p> 16895bb6a25fSPoul-Henning Kamp</div> 16905bb6a25fSPoul-Henning Kamp 16915bb6a25fSPoul-Henning Kamp<div class="handler"> 1692cc68614dSXin LI<h4 id="XML_SetUnknownEncodingHandler">XML_SetUnknownEncodingHandler</h4> 1693cc68614dSXin LI<pre class="setter"> 1694220ed979SColeman Kanevoid XMLCALL 16955bb6a25fSPoul-Henning KampXML_SetUnknownEncodingHandler(XML_Parser p, 16965bb6a25fSPoul-Henning Kamp XML_UnknownEncodingHandler enchandler, 16975bb6a25fSPoul-Henning Kamp void *encodingHandlerData) 16985bb6a25fSPoul-Henning Kamp</pre> 16995bb6a25fSPoul-Henning Kamp<pre class="signature"> 17005bb6a25fSPoul-Henning Kamptypedef int 1701220ed979SColeman Kane(XMLCALL *XML_UnknownEncodingHandler)(void *encodingHandlerData, 17025bb6a25fSPoul-Henning Kamp const XML_Char *name, 17035bb6a25fSPoul-Henning Kamp XML_Encoding *info); 17045bb6a25fSPoul-Henning Kamp 17055bb6a25fSPoul-Henning Kamptypedef struct { 17065bb6a25fSPoul-Henning Kamp int map[256]; 17075bb6a25fSPoul-Henning Kamp void *data; 1708220ed979SColeman Kane int (XMLCALL *convert)(void *data, const char *s); 1709220ed979SColeman Kane void (XMLCALL *release)(void *data); 17105bb6a25fSPoul-Henning Kamp} XML_Encoding; 17115bb6a25fSPoul-Henning Kamp</pre> 1712220ed979SColeman Kane<p>Set a handler to deal with encodings other than the <a 1713220ed979SColeman Kanehref="#builtin_encodings">built in set</a>. This should be done before 17145bb6a25fSPoul-Henning Kamp<code><a href= "#XML_Parse" >XML_Parse</a></code> or <code><a href= 17155bb6a25fSPoul-Henning Kamp"#XML_ParseBuffer" >XML_ParseBuffer</a></code> have been called on the 1716220ed979SColeman Kanegiven parser.</p> <p>If the handler knows how to deal with an encoding 1717220ed979SColeman Kanewith the given name, it should fill in the <code>info</code> data 1718220ed979SColeman Kanestructure and return <code>XML_STATUS_OK</code>. Otherwise it 1719220ed979SColeman Kaneshould return <code>XML_STATUS_ERROR</code>. The handler will be called 1720220ed979SColeman Kaneat most once per parsed (external) entity. The optional application 1721220ed979SColeman Kanedata pointer <code>encodingHandlerData</code> will be passed back to 1722220ed979SColeman Kanethe handler.</p> 17235bb6a25fSPoul-Henning Kamp 17240a48773fSEric van Gyzen<p>The map array contains information for every possible leading 17255bb6a25fSPoul-Henning Kampbyte in a byte sequence. If the corresponding value is >= 0, then it's 17265bb6a25fSPoul-Henning Kampa single byte sequence and the byte encodes that Unicode value. If the 17275bb6a25fSPoul-Henning Kampvalue is -1, then that byte is invalid as the initial byte in a sequence. 17285bb6a25fSPoul-Henning KampIf the value is -n, where n is an integer > 1, then n is the number of 17295bb6a25fSPoul-Henning Kampbytes in the sequence and the actual conversion is accomplished by a 17305bb6a25fSPoul-Henning Kampcall to the function pointed at by convert. This function may return -1 17314543ef51SXin LIif the sequence itself is invalid. The convert pointer may be <code>NULL</code> if 17325bb6a25fSPoul-Henning Kampthere are only single byte codes. The data parameter passed to the convert 17335bb6a25fSPoul-Henning Kampfunction is the data pointer from <code>XML_Encoding</code>. The 1734cc68614dSXin LIstring s is <em>NOT</em> null-terminated and points at the sequence of 17355bb6a25fSPoul-Henning Kampbytes to be converted.</p> 17365bb6a25fSPoul-Henning Kamp 17375bb6a25fSPoul-Henning Kamp<p>The function pointed at by <code>release</code> is called by the 17384543ef51SXin LIparser when it is finished with the encoding. It may be <code>NULL</code>.</p> 17395bb6a25fSPoul-Henning Kamp</div> 17405bb6a25fSPoul-Henning Kamp 17415bb6a25fSPoul-Henning Kamp<div class="handler"> 1742cc68614dSXin LI<h4 id="XML_SetStartNamespaceDeclHandler">XML_SetStartNamespaceDeclHandler</h4> 1743cc68614dSXin LI<pre class="setter"> 1744220ed979SColeman Kanevoid XMLCALL 17455bb6a25fSPoul-Henning KampXML_SetStartNamespaceDeclHandler(XML_Parser p, 17465bb6a25fSPoul-Henning Kamp XML_StartNamespaceDeclHandler start); 17475bb6a25fSPoul-Henning Kamp</pre> 17485bb6a25fSPoul-Henning Kamp<pre class="signature"> 17495bb6a25fSPoul-Henning Kamptypedef void 1750220ed979SColeman Kane(XMLCALL *XML_StartNamespaceDeclHandler)(void *userData, 17515bb6a25fSPoul-Henning Kamp const XML_Char *prefix, 17525bb6a25fSPoul-Henning Kamp const XML_Char *uri); 17535bb6a25fSPoul-Henning Kamp</pre> 17545bb6a25fSPoul-Henning Kamp<p>Set a handler to be called when a namespace is declared. Namespace 17555bb6a25fSPoul-Henning Kampdeclarations occur inside start tags. But the namespace declaration start 17565bb6a25fSPoul-Henning Kamphandler is called before the start tag handler for each namespace declared 17575bb6a25fSPoul-Henning Kampin that start tag.</p> 17585bb6a25fSPoul-Henning Kamp</div> 17595bb6a25fSPoul-Henning Kamp 17605bb6a25fSPoul-Henning Kamp<div class="handler"> 1761cc68614dSXin LI<h4 id="XML_SetEndNamespaceDeclHandler">XML_SetEndNamespaceDeclHandler</h4> 1762cc68614dSXin LI<pre class="setter"> 1763220ed979SColeman Kanevoid XMLCALL 17645bb6a25fSPoul-Henning KampXML_SetEndNamespaceDeclHandler(XML_Parser p, 17655bb6a25fSPoul-Henning Kamp XML_EndNamespaceDeclHandler end); 17665bb6a25fSPoul-Henning Kamp</pre> 17675bb6a25fSPoul-Henning Kamp<pre class="signature"> 17685bb6a25fSPoul-Henning Kamptypedef void 1769220ed979SColeman Kane(XMLCALL *XML_EndNamespaceDeclHandler)(void *userData, 17705bb6a25fSPoul-Henning Kamp const XML_Char *prefix); 17715bb6a25fSPoul-Henning Kamp</pre> 17725bb6a25fSPoul-Henning Kamp<p>Set a handler to be called when leaving the scope of a namespace 17735bb6a25fSPoul-Henning Kampdeclaration. This will be called, for each namespace declaration, 17745bb6a25fSPoul-Henning Kampafter the handler for the end tag of the element in which the 17755bb6a25fSPoul-Henning Kampnamespace was declared.</p> 17765bb6a25fSPoul-Henning Kamp</div> 17775bb6a25fSPoul-Henning Kamp 17785bb6a25fSPoul-Henning Kamp<div class="handler"> 1779cc68614dSXin LI<h4 id="XML_SetNamespaceDeclHandler">XML_SetNamespaceDeclHandler</h4> 1780cc68614dSXin LI<pre class="setter"> 1781220ed979SColeman Kanevoid XMLCALL 17825bb6a25fSPoul-Henning KampXML_SetNamespaceDeclHandler(XML_Parser p, 17835bb6a25fSPoul-Henning Kamp XML_StartNamespaceDeclHandler start, 17845bb6a25fSPoul-Henning Kamp XML_EndNamespaceDeclHandler end) 17855bb6a25fSPoul-Henning Kamp</pre> 1786220ed979SColeman Kane<p>Sets both namespace declaration handlers with a single call.</p> 17875bb6a25fSPoul-Henning Kamp</div> 17885bb6a25fSPoul-Henning Kamp 17895bb6a25fSPoul-Henning Kamp<div class="handler"> 1790cc68614dSXin LI<h4 id="XML_SetXmlDeclHandler">XML_SetXmlDeclHandler</h4> 1791cc68614dSXin LI<pre class="setter"> 1792220ed979SColeman Kanevoid XMLCALL 17935bb6a25fSPoul-Henning KampXML_SetXmlDeclHandler(XML_Parser p, 17945bb6a25fSPoul-Henning Kamp XML_XmlDeclHandler xmldecl); 17955bb6a25fSPoul-Henning Kamp</pre> 17965bb6a25fSPoul-Henning Kamp<pre class="signature"> 17975bb6a25fSPoul-Henning Kamptypedef void 1798220ed979SColeman Kane(XMLCALL *XML_XmlDeclHandler)(void *userData, 17995bb6a25fSPoul-Henning Kamp const XML_Char *version, 18005bb6a25fSPoul-Henning Kamp const XML_Char *encoding, 18015bb6a25fSPoul-Henning Kamp int standalone); 18025bb6a25fSPoul-Henning Kamp</pre> 18035bb6a25fSPoul-Henning Kamp<p>Sets a handler that is called for XML declarations and also for 18045bb6a25fSPoul-Henning Kamptext declarations discovered in external entities. The way to 18054543ef51SXin LIdistinguish is that the <code>version</code> parameter will be <code>NULL</code> 18064543ef51SXin LIfor text declarations. The <code>encoding</code> parameter may be <code>NULL</code> 18075bb6a25fSPoul-Henning Kampfor an XML declaration. The <code>standalone</code> argument will 18085bb6a25fSPoul-Henning Kampcontain -1, 0, or 1 indicating respectively that there was no 18095bb6a25fSPoul-Henning Kampstandalone parameter in the declaration, that it was given as no, or 18105bb6a25fSPoul-Henning Kampthat it was given as yes.</p> 18115bb6a25fSPoul-Henning Kamp</div> 18125bb6a25fSPoul-Henning Kamp 18135bb6a25fSPoul-Henning Kamp<div class="handler"> 1814cc68614dSXin LI<h4 id="XML_SetStartDoctypeDeclHandler">XML_SetStartDoctypeDeclHandler</h4> 1815cc68614dSXin LI<pre class="setter"> 1816220ed979SColeman Kanevoid XMLCALL 18175bb6a25fSPoul-Henning KampXML_SetStartDoctypeDeclHandler(XML_Parser p, 18185bb6a25fSPoul-Henning Kamp XML_StartDoctypeDeclHandler start); 18195bb6a25fSPoul-Henning Kamp</pre> 18205bb6a25fSPoul-Henning Kamp<pre class="signature"> 18215bb6a25fSPoul-Henning Kamptypedef void 1822220ed979SColeman Kane(XMLCALL *XML_StartDoctypeDeclHandler)(void *userData, 18235bb6a25fSPoul-Henning Kamp const XML_Char *doctypeName, 18245bb6a25fSPoul-Henning Kamp const XML_Char *sysid, 18255bb6a25fSPoul-Henning Kamp const XML_Char *pubid, 18265bb6a25fSPoul-Henning Kamp int has_internal_subset); 18275bb6a25fSPoul-Henning Kamp</pre> 18285bb6a25fSPoul-Henning Kamp<p>Set a handler that is called at the start of a DOCTYPE declaration, 18295bb6a25fSPoul-Henning Kampbefore any external or internal subset is parsed. Both <code>sysid</code> 18304543ef51SXin LIand <code>pubid</code> may be <code>NULL</code>. The <code>has_internal_subset</code> 18315bb6a25fSPoul-Henning Kampwill be non-zero if the DOCTYPE declaration has an internal subset.</p> 18325bb6a25fSPoul-Henning Kamp</div> 18335bb6a25fSPoul-Henning Kamp 18345bb6a25fSPoul-Henning Kamp<div class="handler"> 1835cc68614dSXin LI<h4 id="XML_SetEndDoctypeDeclHandler">XML_SetEndDoctypeDeclHandler</h4> 1836cc68614dSXin LI<pre class="setter"> 1837220ed979SColeman Kanevoid XMLCALL 18385bb6a25fSPoul-Henning KampXML_SetEndDoctypeDeclHandler(XML_Parser p, 18395bb6a25fSPoul-Henning Kamp XML_EndDoctypeDeclHandler end); 18405bb6a25fSPoul-Henning Kamp</pre> 18415bb6a25fSPoul-Henning Kamp<pre class="signature"> 18425bb6a25fSPoul-Henning Kamptypedef void 1843220ed979SColeman Kane(XMLCALL *XML_EndDoctypeDeclHandler)(void *userData); 18445bb6a25fSPoul-Henning Kamp</pre> 18455bb6a25fSPoul-Henning Kamp<p>Set a handler that is called at the end of a DOCTYPE declaration, 18465bb6a25fSPoul-Henning Kampafter parsing any external subset.</p> 18475bb6a25fSPoul-Henning Kamp</div> 18485bb6a25fSPoul-Henning Kamp 18495bb6a25fSPoul-Henning Kamp<div class="handler"> 1850cc68614dSXin LI<h4 id="XML_SetDoctypeDeclHandler">XML_SetDoctypeDeclHandler</h4> 1851cc68614dSXin LI<pre class="setter"> 1852220ed979SColeman Kanevoid XMLCALL 18535bb6a25fSPoul-Henning KampXML_SetDoctypeDeclHandler(XML_Parser p, 18545bb6a25fSPoul-Henning Kamp XML_StartDoctypeDeclHandler start, 18555bb6a25fSPoul-Henning Kamp XML_EndDoctypeDeclHandler end); 18565bb6a25fSPoul-Henning Kamp</pre> 18575bb6a25fSPoul-Henning Kamp<p>Set both doctype handlers with one call.</p> 18585bb6a25fSPoul-Henning Kamp</div> 18595bb6a25fSPoul-Henning Kamp 18605bb6a25fSPoul-Henning Kamp<div class="handler"> 1861cc68614dSXin LI<h4 id="XML_SetElementDeclHandler">XML_SetElementDeclHandler</h4> 1862cc68614dSXin LI<pre class="setter"> 1863220ed979SColeman Kanevoid XMLCALL 18645bb6a25fSPoul-Henning KampXML_SetElementDeclHandler(XML_Parser p, 18655bb6a25fSPoul-Henning Kamp XML_ElementDeclHandler eldecl); 18665bb6a25fSPoul-Henning Kamp</pre> 18675bb6a25fSPoul-Henning Kamp<pre class="signature"> 18685bb6a25fSPoul-Henning Kamptypedef void 1869220ed979SColeman Kane(XMLCALL *XML_ElementDeclHandler)(void *userData, 18705bb6a25fSPoul-Henning Kamp const XML_Char *name, 18715bb6a25fSPoul-Henning Kamp XML_Content *model); 18725bb6a25fSPoul-Henning Kamp</pre> 18735bb6a25fSPoul-Henning Kamp<pre class="signature"> 18745bb6a25fSPoul-Henning Kampenum XML_Content_Type { 18755bb6a25fSPoul-Henning Kamp XML_CTYPE_EMPTY = 1, 18765bb6a25fSPoul-Henning Kamp XML_CTYPE_ANY, 18775bb6a25fSPoul-Henning Kamp XML_CTYPE_MIXED, 18785bb6a25fSPoul-Henning Kamp XML_CTYPE_NAME, 18795bb6a25fSPoul-Henning Kamp XML_CTYPE_CHOICE, 18805bb6a25fSPoul-Henning Kamp XML_CTYPE_SEQ 18815bb6a25fSPoul-Henning Kamp}; 18825bb6a25fSPoul-Henning Kamp 18835bb6a25fSPoul-Henning Kampenum XML_Content_Quant { 18845bb6a25fSPoul-Henning Kamp XML_CQUANT_NONE, 18855bb6a25fSPoul-Henning Kamp XML_CQUANT_OPT, 18865bb6a25fSPoul-Henning Kamp XML_CQUANT_REP, 18875bb6a25fSPoul-Henning Kamp XML_CQUANT_PLUS 18885bb6a25fSPoul-Henning Kamp}; 18895bb6a25fSPoul-Henning Kamp 18905bb6a25fSPoul-Henning Kamptypedef struct XML_cp XML_Content; 18915bb6a25fSPoul-Henning Kamp 18925bb6a25fSPoul-Henning Kampstruct XML_cp { 18935bb6a25fSPoul-Henning Kamp enum XML_Content_Type type; 18945bb6a25fSPoul-Henning Kamp enum XML_Content_Quant quant; 18955bb6a25fSPoul-Henning Kamp const XML_Char * name; 18965bb6a25fSPoul-Henning Kamp unsigned int numchildren; 18975bb6a25fSPoul-Henning Kamp XML_Content * children; 18985bb6a25fSPoul-Henning Kamp}; 18995bb6a25fSPoul-Henning Kamp</pre> 19005bb6a25fSPoul-Henning Kamp<p>Sets a handler for element declarations in a DTD. The handler gets 19015bb6a25fSPoul-Henning Kampcalled with the name of the element in the declaration and a pointer 19027ed8e142SXin LIto a structure that contains the element model. It's the user code's 19037ed8e142SXin LIresponsibility to free model when finished with it. See <code> 19047ed8e142SXin LI<a href="#XML_FreeContentModel">XML_FreeContentModel</a></code>. 19057ed8e142SXin LIThere is no need to free the model from the handler, it can be kept 19067ed8e142SXin LIaround and freed at a later stage.</p> 19075bb6a25fSPoul-Henning Kamp 19085bb6a25fSPoul-Henning Kamp<p>The <code>model</code> argument is the root of a tree of 19095bb6a25fSPoul-Henning Kamp<code>XML_Content</code> nodes. If <code>type</code> equals 19105bb6a25fSPoul-Henning Kamp<code>XML_CTYPE_EMPTY</code> or <code>XML_CTYPE_ANY</code>, then 19115bb6a25fSPoul-Henning Kamp<code>quant</code> will be <code>XML_CQUANT_NONE</code>, and the other 19124543ef51SXin LIfields will be zero or <code>NULL</code>. If <code>type</code> is 19135bb6a25fSPoul-Henning Kamp<code>XML_CTYPE_MIXED</code>, then <code>quant</code> will be 19145bb6a25fSPoul-Henning Kamp<code>XML_CQUANT_NONE</code> or <code>XML_CQUANT_REP</code> and 19155bb6a25fSPoul-Henning Kamp<code>numchildren</code> will contain the number of elements that are 19165bb6a25fSPoul-Henning Kampallowed to be mixed in and <code>children</code> points to an array of 19175bb6a25fSPoul-Henning Kamp<code>XML_Content</code> structures that will all have type 19185bb6a25fSPoul-Henning KampXML_CTYPE_NAME with no quantification. Only the root node can be type 19195bb6a25fSPoul-Henning Kamp<code>XML_CTYPE_EMPTY</code>, <code>XML_CTYPE_ANY</code>, or 19205bb6a25fSPoul-Henning Kamp<code>XML_CTYPE_MIXED</code>.</p> 19215bb6a25fSPoul-Henning Kamp 19225bb6a25fSPoul-Henning Kamp<p>For type <code>XML_CTYPE_NAME</code>, the <code>name</code> field 19235bb6a25fSPoul-Henning Kamppoints to the name and the <code>numchildren</code> and 19244543ef51SXin LI<code>children</code> fields will be zero and <code>NULL</code>. The 19255bb6a25fSPoul-Henning Kamp<code>quant</code> field will indicate any quantifiers placed on the 19265bb6a25fSPoul-Henning Kampname.</p> 19275bb6a25fSPoul-Henning Kamp 19285bb6a25fSPoul-Henning Kamp<p>Types <code>XML_CTYPE_CHOICE</code> and <code>XML_CTYPE_SEQ</code> 19295bb6a25fSPoul-Henning Kampindicate a choice or sequence respectively. The 19305bb6a25fSPoul-Henning Kamp<code>numchildren</code> field indicates how many nodes in the choice 19315bb6a25fSPoul-Henning Kampor sequence and <code>children</code> points to the nodes.</p> 19325bb6a25fSPoul-Henning Kamp</div> 19335bb6a25fSPoul-Henning Kamp 19345bb6a25fSPoul-Henning Kamp<div class="handler"> 1935cc68614dSXin LI<h4 id="XML_SetAttlistDeclHandler">XML_SetAttlistDeclHandler</h4> 1936cc68614dSXin LI<pre class="setter"> 1937220ed979SColeman Kanevoid XMLCALL 19385bb6a25fSPoul-Henning KampXML_SetAttlistDeclHandler(XML_Parser p, 19395bb6a25fSPoul-Henning Kamp XML_AttlistDeclHandler attdecl); 19405bb6a25fSPoul-Henning Kamp</pre> 19415bb6a25fSPoul-Henning Kamp<pre class="signature"> 19425bb6a25fSPoul-Henning Kamptypedef void 1943220ed979SColeman Kane(XMLCALL *XML_AttlistDeclHandler)(void *userData, 19445bb6a25fSPoul-Henning Kamp const XML_Char *elname, 19455bb6a25fSPoul-Henning Kamp const XML_Char *attname, 19465bb6a25fSPoul-Henning Kamp const XML_Char *att_type, 19475bb6a25fSPoul-Henning Kamp const XML_Char *dflt, 19485bb6a25fSPoul-Henning Kamp int isrequired); 19495bb6a25fSPoul-Henning Kamp</pre> 19505bb6a25fSPoul-Henning Kamp<p>Set a handler for attlist declarations in the DTD. This handler is 19515bb6a25fSPoul-Henning Kampcalled for <em>each</em> attribute. So a single attlist declaration 19525bb6a25fSPoul-Henning Kampwith multiple attributes declared will generate multiple calls to this 19535bb6a25fSPoul-Henning Kamphandler. The <code>elname</code> parameter returns the name of the 19545bb6a25fSPoul-Henning Kampelement for which the attribute is being declared. The attribute name 19555bb6a25fSPoul-Henning Kampis in the <code>attname</code> parameter. The attribute type is in the 19565bb6a25fSPoul-Henning Kamp<code>att_type</code> parameter. It is the string representing the 19575bb6a25fSPoul-Henning Kamptype in the declaration with whitespace removed.</p> 19585bb6a25fSPoul-Henning Kamp 19595bb6a25fSPoul-Henning Kamp<p>The <code>dflt</code> parameter holds the default value. It will be 19604543ef51SXin LI<code>NULL</code> in the case of "#IMPLIED" or "#REQUIRED" attributes. You can 19615bb6a25fSPoul-Henning Kampdistinguish these two cases by checking the <code>isrequired</code> 19625bb6a25fSPoul-Henning Kampparameter, which will be true in the case of "#REQUIRED" attributes. 19635bb6a25fSPoul-Henning KampAttributes which are "#FIXED" will have also have a true 19644543ef51SXin LI<code>isrequired</code>, but they will have the non-<code>NULL</code> fixed value 19655bb6a25fSPoul-Henning Kampin the <code>dflt</code> parameter.</p> 19665bb6a25fSPoul-Henning Kamp</div> 19675bb6a25fSPoul-Henning Kamp 19685bb6a25fSPoul-Henning Kamp<div class="handler"> 1969cc68614dSXin LI<h4 id="XML_SetEntityDeclHandler">XML_SetEntityDeclHandler</h4> 1970cc68614dSXin LI<pre class="setter"> 1971220ed979SColeman Kanevoid XMLCALL 19725bb6a25fSPoul-Henning KampXML_SetEntityDeclHandler(XML_Parser p, 19735bb6a25fSPoul-Henning Kamp XML_EntityDeclHandler handler); 19745bb6a25fSPoul-Henning Kamp</pre> 19755bb6a25fSPoul-Henning Kamp<pre class="signature"> 19765bb6a25fSPoul-Henning Kamptypedef void 1977220ed979SColeman Kane(XMLCALL *XML_EntityDeclHandler)(void *userData, 19785bb6a25fSPoul-Henning Kamp const XML_Char *entityName, 19795bb6a25fSPoul-Henning Kamp int is_parameter_entity, 19805bb6a25fSPoul-Henning Kamp const XML_Char *value, 19815bb6a25fSPoul-Henning Kamp int value_length, 19825bb6a25fSPoul-Henning Kamp const XML_Char *base, 19835bb6a25fSPoul-Henning Kamp const XML_Char *systemId, 19845bb6a25fSPoul-Henning Kamp const XML_Char *publicId, 19855bb6a25fSPoul-Henning Kamp const XML_Char *notationName); 19865bb6a25fSPoul-Henning Kamp</pre> 19875bb6a25fSPoul-Henning Kamp<p>Sets a handler that will be called for all entity declarations. 19885bb6a25fSPoul-Henning KampThe <code>is_parameter_entity</code> argument will be non-zero in the 19895bb6a25fSPoul-Henning Kampcase of parameter entities and zero otherwise.</p> 19905bb6a25fSPoul-Henning Kamp 19915bb6a25fSPoul-Henning Kamp<p>For internal entities (<code><!ENTITY foo "bar"></code>), 19924543ef51SXin LI<code>value</code> will be non-<code>NULL</code> and <code>systemId</code>, 19934543ef51SXin LI<code>publicId</code>, and <code>notationName</code> will all be <code>NULL</code>. 19944543ef51SXin LIThe value string is <em>not</em> null-terminated; the length is 19955bb6a25fSPoul-Henning Kampprovided in the <code>value_length</code> parameter. Do not use 19965bb6a25fSPoul-Henning Kamp<code>value_length</code> to test for internal entities, since it is 19975bb6a25fSPoul-Henning Kamplegal to have zero-length values. Instead check for whether or not 19984543ef51SXin LI<code>value</code> is <code>NULL</code>.</p> <p>The <code>notationName</code> 19994543ef51SXin LIargument will have a non-<code>NULL</code> value only for unparsed entity 20005bb6a25fSPoul-Henning Kampdeclarations.</p> 20015bb6a25fSPoul-Henning Kamp</div> 20025bb6a25fSPoul-Henning Kamp 20035bb6a25fSPoul-Henning Kamp<div class="handler"> 2004cc68614dSXin LI<h4 id="XML_SetUnparsedEntityDeclHandler">XML_SetUnparsedEntityDeclHandler</h4> 2005cc68614dSXin LI<pre class="setter"> 2006220ed979SColeman Kanevoid XMLCALL 20075bb6a25fSPoul-Henning KampXML_SetUnparsedEntityDeclHandler(XML_Parser p, 20085bb6a25fSPoul-Henning Kamp XML_UnparsedEntityDeclHandler h) 20095bb6a25fSPoul-Henning Kamp</pre> 20105bb6a25fSPoul-Henning Kamp<pre class="signature"> 20115bb6a25fSPoul-Henning Kamptypedef void 2012220ed979SColeman Kane(XMLCALL *XML_UnparsedEntityDeclHandler)(void *userData, 20135bb6a25fSPoul-Henning Kamp const XML_Char *entityName, 20145bb6a25fSPoul-Henning Kamp const XML_Char *base, 20155bb6a25fSPoul-Henning Kamp const XML_Char *systemId, 20165bb6a25fSPoul-Henning Kamp const XML_Char *publicId, 20175bb6a25fSPoul-Henning Kamp const XML_Char *notationName); 20185bb6a25fSPoul-Henning Kamp</pre> 20195bb6a25fSPoul-Henning Kamp<p>Set a handler that receives declarations of unparsed entities. These 20205bb6a25fSPoul-Henning Kampare entity declarations that have a notation (NDATA) field:</p> 20215bb6a25fSPoul-Henning Kamp 20225bb6a25fSPoul-Henning Kamp<div id="eg"><pre> 20235bb6a25fSPoul-Henning Kamp<!ENTITY logo SYSTEM "images/logo.gif" NDATA gif> 20245bb6a25fSPoul-Henning Kamp</pre></div> 20255bb6a25fSPoul-Henning Kamp<p>This handler is obsolete and is provided for backwards 20265bb6a25fSPoul-Henning Kampcompatibility. Use instead <a href= "#XML_SetEntityDeclHandler" 20275bb6a25fSPoul-Henning Kamp>XML_SetEntityDeclHandler</a>.</p> 20285bb6a25fSPoul-Henning Kamp</div> 20295bb6a25fSPoul-Henning Kamp 20305bb6a25fSPoul-Henning Kamp<div class="handler"> 2031cc68614dSXin LI<h4 id="XML_SetNotationDeclHandler">XML_SetNotationDeclHandler</h4> 2032cc68614dSXin LI<pre class="setter"> 2033220ed979SColeman Kanevoid XMLCALL 20345bb6a25fSPoul-Henning KampXML_SetNotationDeclHandler(XML_Parser p, 20355bb6a25fSPoul-Henning Kamp XML_NotationDeclHandler h) 20365bb6a25fSPoul-Henning Kamp</pre> 20375bb6a25fSPoul-Henning Kamp<pre class="signature"> 20385bb6a25fSPoul-Henning Kamptypedef void 2039220ed979SColeman Kane(XMLCALL *XML_NotationDeclHandler)(void *userData, 20405bb6a25fSPoul-Henning Kamp const XML_Char *notationName, 20415bb6a25fSPoul-Henning Kamp const XML_Char *base, 20425bb6a25fSPoul-Henning Kamp const XML_Char *systemId, 20435bb6a25fSPoul-Henning Kamp const XML_Char *publicId); 20445bb6a25fSPoul-Henning Kamp</pre> 20455bb6a25fSPoul-Henning Kamp<p>Set a handler that receives notation declarations.</p> 20465bb6a25fSPoul-Henning Kamp</div> 20475bb6a25fSPoul-Henning Kamp 20485bb6a25fSPoul-Henning Kamp<div class="handler"> 2049cc68614dSXin LI<h4 id="XML_SetNotStandaloneHandler">XML_SetNotStandaloneHandler</h4> 2050cc68614dSXin LI<pre class="setter"> 2051220ed979SColeman Kanevoid XMLCALL 20525bb6a25fSPoul-Henning KampXML_SetNotStandaloneHandler(XML_Parser p, 20535bb6a25fSPoul-Henning Kamp XML_NotStandaloneHandler h) 20545bb6a25fSPoul-Henning Kamp</pre> 20555bb6a25fSPoul-Henning Kamp<pre class="signature"> 20565bb6a25fSPoul-Henning Kamptypedef int 2057220ed979SColeman Kane(XMLCALL *XML_NotStandaloneHandler)(void *userData); 20585bb6a25fSPoul-Henning Kamp</pre> 20595bb6a25fSPoul-Henning Kamp<p>Set a handler that is called if the document is not "standalone". 20605bb6a25fSPoul-Henning KampThis happens when there is an external subset or a reference to a 20615bb6a25fSPoul-Henning Kampparameter entity, but does not have standalone set to "yes" in an XML 2062220ed979SColeman Kanedeclaration. If this handler returns <code>XML_STATUS_ERROR</code>, 2063220ed979SColeman Kanethen the parser will throw an <code>XML_ERROR_NOT_STANDALONE</code> 2064220ed979SColeman Kaneerror.</p> 20655bb6a25fSPoul-Henning Kamp</div> 20665bb6a25fSPoul-Henning Kamp 20675bb6a25fSPoul-Henning Kamp<h3><a name="position">Parse position and error reporting functions</a></h3> 20685bb6a25fSPoul-Henning Kamp 20695bb6a25fSPoul-Henning Kamp<p>These are the functions you'll want to call when the parse 2070220ed979SColeman Kanefunctions return <code>XML_STATUS_ERROR</code> (a parse error has 2071220ed979SColeman Kaneoccurred), although the position reporting functions are useful outside 2072220ed979SColeman Kaneof errors. The position reported is the byte position (in the original 2073220ed979SColeman Kanedocument or entity encoding) of the first of the sequence of 2074220ed979SColeman Kanecharacters that generated the current event (or the error that caused 2075220ed979SColeman Kanethe parse functions to return <code>XML_STATUS_ERROR</code>.) The 2076cc68614dSXin LIexceptions are callbacks triggered by declarations in the document 2077220ed979SColeman Kaneprologue, in which case they exact position reported is somewhere in the 2078220ed979SColeman Kanerelevant markup, but not necessarily as meaningful as for other 2079220ed979SColeman Kaneevents.</p> 20805bb6a25fSPoul-Henning Kamp 20815bb6a25fSPoul-Henning Kamp<p>The position reporting functions are accurate only outside of the 20825bb6a25fSPoul-Henning KampDTD. In other words, they usually return bogus information when 20835bb6a25fSPoul-Henning Kampcalled from within a DTD declaration handler.</p> 20845bb6a25fSPoul-Henning Kamp 2085cc68614dSXin LI<h4 id="XML_GetErrorCode">XML_GetErrorCode</h4> 2086cc68614dSXin LI<pre class="fcndec"> 2087220ed979SColeman Kaneenum XML_Error XMLCALL 20885bb6a25fSPoul-Henning KampXML_GetErrorCode(XML_Parser p); 20895bb6a25fSPoul-Henning Kamp</pre> 20905bb6a25fSPoul-Henning Kamp<div class="fcndef"> 20915bb6a25fSPoul-Henning KampReturn what type of error has occurred. 20925bb6a25fSPoul-Henning Kamp</div> 20935bb6a25fSPoul-Henning Kamp 2094cc68614dSXin LI<h4 id="XML_ErrorString">XML_ErrorString</h4> 2095cc68614dSXin LI<pre class="fcndec"> 2096220ed979SColeman Kaneconst XML_LChar * XMLCALL 2097220ed979SColeman KaneXML_ErrorString(enum XML_Error code); 20985bb6a25fSPoul-Henning Kamp</pre> 20995bb6a25fSPoul-Henning Kamp<div class="fcndef"> 21005bb6a25fSPoul-Henning KampReturn a string describing the error corresponding to code. 21015bb6a25fSPoul-Henning KampThe code should be one of the enums that can be returned from 21025bb6a25fSPoul-Henning Kamp<code><a href= "#XML_GetErrorCode" >XML_GetErrorCode</a></code>. 21035bb6a25fSPoul-Henning Kamp</div> 21045bb6a25fSPoul-Henning Kamp 2105cc68614dSXin LI<h4 id="XML_GetCurrentByteIndex">XML_GetCurrentByteIndex</h4> 2106cc68614dSXin LI<pre class="fcndec"> 2107220ed979SColeman KaneXML_Index XMLCALL 21085bb6a25fSPoul-Henning KampXML_GetCurrentByteIndex(XML_Parser p); 21095bb6a25fSPoul-Henning Kamp</pre> 21105bb6a25fSPoul-Henning Kamp<div class="fcndef"> 2111220ed979SColeman KaneReturn the byte offset of the position. This always corresponds to 2112220ed979SColeman Kanethe values returned by <code><a href= "#XML_GetCurrentLineNumber" 2113220ed979SColeman Kane>XML_GetCurrentLineNumber</a></code> and <code><a href= 2114220ed979SColeman Kane"#XML_GetCurrentColumnNumber" >XML_GetCurrentColumnNumber</a></code>. 21155bb6a25fSPoul-Henning Kamp</div> 21165bb6a25fSPoul-Henning Kamp 2117cc68614dSXin LI<h4 id="XML_GetCurrentLineNumber">XML_GetCurrentLineNumber</h4> 2118cc68614dSXin LI<pre class="fcndec"> 2119220ed979SColeman KaneXML_Size XMLCALL 21205bb6a25fSPoul-Henning KampXML_GetCurrentLineNumber(XML_Parser p); 21215bb6a25fSPoul-Henning Kamp</pre> 21225bb6a25fSPoul-Henning Kamp<div class="fcndef"> 2123220ed979SColeman KaneReturn the line number of the position. The first line is reported as 2124220ed979SColeman Kane<code>1</code>. 21255bb6a25fSPoul-Henning Kamp</div> 21265bb6a25fSPoul-Henning Kamp 2127cc68614dSXin LI<h4 id="XML_GetCurrentColumnNumber">XML_GetCurrentColumnNumber</h4> 2128cc68614dSXin LI<pre class="fcndec"> 2129220ed979SColeman KaneXML_Size XMLCALL 21305bb6a25fSPoul-Henning KampXML_GetCurrentColumnNumber(XML_Parser p); 21315bb6a25fSPoul-Henning Kamp</pre> 21325bb6a25fSPoul-Henning Kamp<div class="fcndef"> 21335bb6a25fSPoul-Henning KampReturn the offset, from the beginning of the current line, of 21345bb6a25fSPoul-Henning Kampthe position. 21355bb6a25fSPoul-Henning Kamp</div> 21365bb6a25fSPoul-Henning Kamp 2137cc68614dSXin LI<h4 id="XML_GetCurrentByteCount">XML_GetCurrentByteCount</h4> 2138cc68614dSXin LI<pre class="fcndec"> 2139220ed979SColeman Kaneint XMLCALL 21405bb6a25fSPoul-Henning KampXML_GetCurrentByteCount(XML_Parser p); 21415bb6a25fSPoul-Henning Kamp</pre> 21425bb6a25fSPoul-Henning Kamp<div class="fcndef"> 21435bb6a25fSPoul-Henning KampReturn the number of bytes in the current event. Returns 21445bb6a25fSPoul-Henning Kamp<code>0</code> if the event is inside a reference to an internal 21455bb6a25fSPoul-Henning Kampentity and for the end-tag event for empty element tags (the later can 21465bb6a25fSPoul-Henning Kampbe used to distinguish empty-element tags from empty elements using 21475bb6a25fSPoul-Henning Kampseparate start and end tags). 21485bb6a25fSPoul-Henning Kamp</div> 21495bb6a25fSPoul-Henning Kamp 2150cc68614dSXin LI<h4 id="XML_GetInputContext">XML_GetInputContext</h4> 2151cc68614dSXin LI<pre class="fcndec"> 2152220ed979SColeman Kaneconst char * XMLCALL 21535bb6a25fSPoul-Henning KampXML_GetInputContext(XML_Parser p, 21545bb6a25fSPoul-Henning Kamp int *offset, 21555bb6a25fSPoul-Henning Kamp int *size); 21565bb6a25fSPoul-Henning Kamp</pre> 21575bb6a25fSPoul-Henning Kamp<div class="fcndef"> 21585bb6a25fSPoul-Henning Kamp 21595bb6a25fSPoul-Henning Kamp<p>Returns the parser's input buffer, sets the integer pointed at by 21605bb6a25fSPoul-Henning Kamp<code>offset</code> to the offset within this buffer of the current 21615bb6a25fSPoul-Henning Kampparse position, and set the integer pointed at by <code>size</code> to 21625bb6a25fSPoul-Henning Kampthe size of the returned buffer.</p> 21635bb6a25fSPoul-Henning Kamp 21645bb6a25fSPoul-Henning Kamp<p>This should only be called from within a handler during an active 21655bb6a25fSPoul-Henning Kampparse and the returned buffer should only be referred to from within 21665bb6a25fSPoul-Henning Kampthe handler that made the call. This input buffer contains the 21675bb6a25fSPoul-Henning Kampuntranslated bytes of the input.</p> 21685bb6a25fSPoul-Henning Kamp 21695bb6a25fSPoul-Henning Kamp<p>Only a limited amount of context is kept, so if the event 21705bb6a25fSPoul-Henning Kamptriggering a call spans over a very large amount of input, the actual 21715bb6a25fSPoul-Henning Kampparse position may be before the beginning of the buffer.</p> 2172220ed979SColeman Kane 21734543ef51SXin LI<p>If <code>XML_CONTEXT_BYTES</code> is zero, this will always 21744543ef51SXin LIreturn <code>NULL</code>.</p> 21755bb6a25fSPoul-Henning Kamp</div> 21765bb6a25fSPoul-Henning Kamp 21774543ef51SXin LI<h3><a name="attack-protection">Attack Protection</a><a name="billion-laughs"></a></h3> 2178cc68614dSXin LI 2179cc68614dSXin LI<h4 id="XML_SetBillionLaughsAttackProtectionMaximumAmplification">XML_SetBillionLaughsAttackProtectionMaximumAmplification</h4> 2180cc68614dSXin LI<pre class="fcndec"> 2181cc68614dSXin LI/* Added in Expat 2.4.0. */ 2182cc68614dSXin LIXML_Bool XMLCALL 2183cc68614dSXin LIXML_SetBillionLaughsAttackProtectionMaximumAmplification(XML_Parser p, 2184cc68614dSXin LI float maximumAmplificationFactor); 2185cc68614dSXin LI</pre> 2186cc68614dSXin LI<div class="fcndef"> 2187cc68614dSXin LI <p> 2188cc68614dSXin LI Sets the maximum tolerated amplification factor 2189cc68614dSXin LI for protection against 2190cc68614dSXin LI <a href="https://en.wikipedia.org/wiki/Billion_laughs_attack">billion laughs attacks</a> 2191cc68614dSXin LI (default: <code>100.0</code>) 2192cc68614dSXin LI of parser <code>p</code> to <code>maximumAmplificationFactor</code>, and 2193cc68614dSXin LI returns <code>XML_TRUE</code> upon success and <code>XML_FALSE</code> upon error. 2194cc68614dSXin LI </p> 2195cc68614dSXin LI 2196cc68614dSXin LI The amplification factor is calculated as .. 2197cc68614dSXin LI <pre> 2198cc68614dSXin LI amplification := (direct + indirect) / direct 2199cc68614dSXin LI </pre> 2200cc68614dSXin LI .. while parsing, whereas 2201cc68614dSXin LI <code>direct</code> is the number of bytes read from the primary document in parsing and 2202cc68614dSXin LI <code>indirect</code> is the number of bytes added by expanding entities and reading of external DTD files, combined. 2203cc68614dSXin LI 2204cc68614dSXin LI <p>For a call to <code>XML_SetBillionLaughsAttackProtectionMaximumAmplification</code> to succeed:</p> 2205cc68614dSXin LI <ul> 2206cc68614dSXin LI <li>parser <code>p</code> must be a non-<code>NULL</code> root parser (without any parent parsers) and</li> 2207cc68614dSXin LI <li><code>maximumAmplificationFactor</code> must be non-<code>NaN</code> and greater than or equal to <code>1.0</code>.</li> 2208cc68614dSXin LI </ul> 2209cc68614dSXin LI 2210cc68614dSXin LI <p> 2211cc68614dSXin LI <strong>Note:</strong> 2212cc68614dSXin LI If you ever need to increase this value for non-attack payload, 2213cc68614dSXin LI please <a href="https://github.com/libexpat/libexpat/issues">file a bug report</a>. 2214cc68614dSXin LI </p> 2215cc68614dSXin LI 2216cc68614dSXin LI <p> 2217cc68614dSXin LI <strong>Note:</strong> 2218cc68614dSXin LI Peak amplifications 2219cc68614dSXin LI of factor 15,000 for the entire payload and 2220cc68614dSXin LI of factor 30,000 in the middle of parsing 2221cc68614dSXin LI have been observed with small benign files in practice. 2222cc68614dSXin LI 2223cc68614dSXin LI So if you do reduce the maximum allowed amplification, 2224cc68614dSXin LI please make sure that the activation threshold is still big enough 2225cc68614dSXin LI to not end up with undesired false positives (i.e. benign files being rejected). 2226cc68614dSXin LI </p> 2227cc68614dSXin LI</div> 2228cc68614dSXin LI 2229cc68614dSXin LI<h4 id="XML_SetBillionLaughsAttackProtectionActivationThreshold">XML_SetBillionLaughsAttackProtectionActivationThreshold</h4> 2230cc68614dSXin LI<pre class="fcndec"> 2231cc68614dSXin LI/* Added in Expat 2.4.0. */ 2232cc68614dSXin LIXML_Bool XMLCALL 2233cc68614dSXin LIXML_SetBillionLaughsAttackProtectionActivationThreshold(XML_Parser p, 2234cc68614dSXin LI unsigned long long activationThresholdBytes); 2235cc68614dSXin LI</pre> 2236cc68614dSXin LI<div class="fcndef"> 2237cc68614dSXin LI <p> 2238cc68614dSXin LI Sets number of output bytes (including amplification from entity expansion and reading DTD files) 2239cc68614dSXin LI needed to activate protection against 2240cc68614dSXin LI <a href="https://en.wikipedia.org/wiki/Billion_laughs_attack">billion laughs attacks</a> 2241cc68614dSXin LI (default: <code>8 MiB</code>) 2242cc68614dSXin LI of parser <code>p</code> to <code>activationThresholdBytes</code>, and 2243cc68614dSXin LI returns <code>XML_TRUE</code> upon success and <code>XML_FALSE</code> upon error. 2244cc68614dSXin LI </p> 2245cc68614dSXin LI 2246cc68614dSXin LI <p>For a call to <code>XML_SetBillionLaughsAttackProtectionActivationThreshold</code> to succeed:</p> 2247cc68614dSXin LI <ul> 2248cc68614dSXin LI <li>parser <code>p</code> must be a non-<code>NULL</code> root parser (without any parent parsers).</li> 2249cc68614dSXin LI </ul> 2250cc68614dSXin LI 2251cc68614dSXin LI <p> 2252cc68614dSXin LI <strong>Note:</strong> 2253cc68614dSXin LI If you ever need to increase this value for non-attack payload, 2254cc68614dSXin LI please <a href="https://github.com/libexpat/libexpat/issues">file a bug report</a>. 2255cc68614dSXin LI </p> 2256cc68614dSXin LI 2257cc68614dSXin LI <p> 2258cc68614dSXin LI <strong>Note:</strong> 2259cc68614dSXin LI Activation thresholds below 4 MiB are known to break support for 2260cc68614dSXin LI <a href="https://en.wikipedia.org/wiki/Darwin_Information_Typing_Architecture">DITA</a> 1.3 payload 2261cc68614dSXin LI and are hence not recommended. 2262cc68614dSXin LI </p> 2263cc68614dSXin LI</div> 2264cc68614dSXin LI 22654543ef51SXin LI<h4 id="XML_SetReparseDeferralEnabled">XML_SetReparseDeferralEnabled</h4> 22664543ef51SXin LI<pre class="fcndec"> 22674543ef51SXin LI/* Added in Expat 2.6.0. */ 22684543ef51SXin LIXML_Bool XMLCALL 22694543ef51SXin LIXML_SetReparseDeferralEnabled(XML_Parser parser, XML_Bool enabled); 22704543ef51SXin LI</pre> 22714543ef51SXin LI<div class="fcndef"> 22724543ef51SXin LI <p> 22734543ef51SXin LI Large tokens may require many parse calls before enough data is available for Expat to parse it in full. 22744543ef51SXin LI If Expat retried parsing the token on every parse call, parsing could take quadratic time. 22754543ef51SXin LI To avoid this, Expat only retries once a significant amount of new data is available. 22764543ef51SXin LI This function allows disabling this behavior. 22774543ef51SXin LI </p> 22784543ef51SXin LI <p> 22794543ef51SXin LI The <code>enabled</code> argument should be <code>XML_TRUE</code> or <code>XML_FALSE</code>. 22804543ef51SXin LI </p> 22814543ef51SXin LI <p> 22824543ef51SXin LI Returns <code>XML_TRUE</code> on success, and <code>XML_FALSE</code> on error. 22834543ef51SXin LI </p> 22844543ef51SXin LI</div> 22854543ef51SXin LI 22865bb6a25fSPoul-Henning Kamp<h3><a name="miscellaneous">Miscellaneous functions</a></h3> 22875bb6a25fSPoul-Henning Kamp 22885bb6a25fSPoul-Henning Kamp<p>The functions in this section either obtain state information from 22890a48773fSEric van Gyzenthe parser or can be used to dynamically set parser options.</p> 22905bb6a25fSPoul-Henning Kamp 2291cc68614dSXin LI<h4 id="XML_SetUserData">XML_SetUserData</h4> 2292cc68614dSXin LI<pre class="fcndec"> 2293220ed979SColeman Kanevoid XMLCALL 22945bb6a25fSPoul-Henning KampXML_SetUserData(XML_Parser p, 22955bb6a25fSPoul-Henning Kamp void *userData); 22965bb6a25fSPoul-Henning Kamp</pre> 22975bb6a25fSPoul-Henning Kamp<div class="fcndef"> 22985bb6a25fSPoul-Henning KampThis sets the user data pointer that gets passed to handlers. It 22995bb6a25fSPoul-Henning Kampoverwrites any previous value for this pointer. Note that the 23005bb6a25fSPoul-Henning Kampapplication is responsible for freeing the memory associated with 23015bb6a25fSPoul-Henning Kamp<code>userData</code> when it is finished with the parser. So if you 23025bb6a25fSPoul-Henning Kampcall this when there's already a pointer there, and you haven't freed 23035bb6a25fSPoul-Henning Kampthe memory associated with it, then you've probably just leaked 23045bb6a25fSPoul-Henning Kampmemory. 23055bb6a25fSPoul-Henning Kamp</div> 23065bb6a25fSPoul-Henning Kamp 2307cc68614dSXin LI<h4 id="XML_GetUserData">XML_GetUserData</h4> 2308cc68614dSXin LI<pre class="fcndec"> 2309220ed979SColeman Kanevoid * XMLCALL 23105bb6a25fSPoul-Henning KampXML_GetUserData(XML_Parser p); 23115bb6a25fSPoul-Henning Kamp</pre> 23125bb6a25fSPoul-Henning Kamp<div class="fcndef"> 23135bb6a25fSPoul-Henning KampThis returns the user data pointer that gets passed to handlers. 23145bb6a25fSPoul-Henning KampIt is actually implemented as a macro. 23155bb6a25fSPoul-Henning Kamp</div> 23165bb6a25fSPoul-Henning Kamp 2317cc68614dSXin LI<h4 id="XML_UseParserAsHandlerArg">XML_UseParserAsHandlerArg</h4> 2318cc68614dSXin LI<pre class="fcndec"> 2319220ed979SColeman Kanevoid XMLCALL 23205bb6a25fSPoul-Henning KampXML_UseParserAsHandlerArg(XML_Parser p); 23215bb6a25fSPoul-Henning Kamp</pre> 23225bb6a25fSPoul-Henning Kamp<div class="fcndef"> 2323220ed979SColeman KaneAfter this is called, handlers receive the parser in their 2324220ed979SColeman Kane<code>userData</code> arguments. The user data can still be obtained 2325220ed979SColeman Kaneusing the <code><a href= "#XML_GetUserData" 2326220ed979SColeman Kane>XML_GetUserData</a></code> function. 23275bb6a25fSPoul-Henning Kamp</div> 23285bb6a25fSPoul-Henning Kamp 2329cc68614dSXin LI<h4 id="XML_SetBase">XML_SetBase</h4> 2330cc68614dSXin LI<pre class="fcndec"> 2331220ed979SColeman Kaneenum XML_Status XMLCALL 23325bb6a25fSPoul-Henning KampXML_SetBase(XML_Parser p, 23335bb6a25fSPoul-Henning Kamp const XML_Char *base); 23345bb6a25fSPoul-Henning Kamp</pre> 23355bb6a25fSPoul-Henning Kamp<div class="fcndef"> 23365bb6a25fSPoul-Henning KampSet the base to be used for resolving relative URIs in system 2337220ed979SColeman Kaneidentifiers. The return value is <code>XML_STATUS_ERROR</code> if 2338220ed979SColeman Kanethere's no memory to store base, otherwise it's 2339220ed979SColeman Kane<code>XML_STATUS_OK</code>. 23405bb6a25fSPoul-Henning Kamp</div> 23415bb6a25fSPoul-Henning Kamp 2342cc68614dSXin LI<h4 id="XML_GetBase">XML_GetBase</h4> 2343cc68614dSXin LI<pre class="fcndec"> 2344220ed979SColeman Kaneconst XML_Char * XMLCALL 23455bb6a25fSPoul-Henning KampXML_GetBase(XML_Parser p); 23465bb6a25fSPoul-Henning Kamp</pre> 23475bb6a25fSPoul-Henning Kamp<div class="fcndef"> 23485bb6a25fSPoul-Henning KampReturn the base for resolving relative URIs. 23495bb6a25fSPoul-Henning Kamp</div> 23505bb6a25fSPoul-Henning Kamp 2351cc68614dSXin LI<h4 id="XML_GetSpecifiedAttributeCount">XML_GetSpecifiedAttributeCount</h4> 2352cc68614dSXin LI<pre class="fcndec"> 2353220ed979SColeman Kaneint XMLCALL 23545bb6a25fSPoul-Henning KampXML_GetSpecifiedAttributeCount(XML_Parser p); 23555bb6a25fSPoul-Henning Kamp</pre> 23565bb6a25fSPoul-Henning Kamp<div class="fcndef"> 23575bb6a25fSPoul-Henning KampWhen attributes are reported to the start handler in the atts vector, 23585bb6a25fSPoul-Henning Kampattributes that were explicitly set in the element occur before any 23595bb6a25fSPoul-Henning Kampattributes that receive their value from default information in an 23605bb6a25fSPoul-Henning KampATTLIST declaration. This function returns the number of attributes 23615bb6a25fSPoul-Henning Kampthat were explicitly set times two, thus giving the offset in the 23625bb6a25fSPoul-Henning Kamp<code>atts</code> array passed to the start tag handler of the first 23635bb6a25fSPoul-Henning Kampattribute set due to defaults. It supplies information for the last 23645bb6a25fSPoul-Henning Kampcall to a start handler. If called inside a start handler, then that 23655bb6a25fSPoul-Henning Kampmeans the current call. 23665bb6a25fSPoul-Henning Kamp</div> 23675bb6a25fSPoul-Henning Kamp 2368cc68614dSXin LI<h4 id="XML_GetIdAttributeIndex">XML_GetIdAttributeIndex</h4> 2369cc68614dSXin LI<pre class="fcndec"> 2370220ed979SColeman Kaneint XMLCALL 23715bb6a25fSPoul-Henning KampXML_GetIdAttributeIndex(XML_Parser p); 23725bb6a25fSPoul-Henning Kamp</pre> 23735bb6a25fSPoul-Henning Kamp<div class="fcndef"> 23745bb6a25fSPoul-Henning KampReturns the index of the ID attribute passed in the atts array in the 23755bb6a25fSPoul-Henning Kamplast call to <code><a href= "#XML_StartElementHandler" 23765bb6a25fSPoul-Henning Kamp>XML_StartElementHandler</a></code>, or -1 if there is no ID 23775bb6a25fSPoul-Henning Kampattribute. If called inside a start handler, then that means the 23785bb6a25fSPoul-Henning Kampcurrent call. 23795bb6a25fSPoul-Henning Kamp</div> 23805bb6a25fSPoul-Henning Kamp 2381cc68614dSXin LI<h4 id="XML_GetAttributeInfo">XML_GetAttributeInfo</h4> 2382cc68614dSXin LI<pre class="fcndec"> 2383e3466a89SXin LIconst XML_AttrInfo * XMLCALL 2384e3466a89SXin LIXML_GetAttributeInfo(XML_Parser parser); 2385e3466a89SXin LI</pre> 2386e3466a89SXin LI<pre class="signature"> 2387e3466a89SXin LItypedef struct { 2388e3466a89SXin LI XML_Index nameStart; /* Offset to beginning of the attribute name. */ 2389e3466a89SXin LI XML_Index nameEnd; /* Offset after the attribute name's last byte. */ 2390e3466a89SXin LI XML_Index valueStart; /* Offset to beginning of the attribute value. */ 2391e3466a89SXin LI XML_Index valueEnd; /* Offset after the attribute value's last byte. */ 2392e3466a89SXin LI} XML_AttrInfo; 2393e3466a89SXin LI</pre> 2394e3466a89SXin LI<div class="fcndef"> 2395e3466a89SXin LIReturns an array of <code>XML_AttrInfo</code> structures for the 2396e3466a89SXin LIattribute/value pairs passed in the last call to the 2397e3466a89SXin LI<code>XML_StartElementHandler</code> that were specified 2398e3466a89SXin LIin the start-tag rather than defaulted. Each attribute/value pair counts 2399e3466a89SXin LIas 1; thus the number of entries in the array is 2400e3466a89SXin LI<code>XML_GetSpecifiedAttributeCount(parser) / 2</code>. 2401e3466a89SXin LI</div> 2402e3466a89SXin LI 2403cc68614dSXin LI<h4 id="XML_SetEncoding">XML_SetEncoding</h4> 2404cc68614dSXin LI<pre class="fcndec"> 2405220ed979SColeman Kaneenum XML_Status XMLCALL 24065bb6a25fSPoul-Henning KampXML_SetEncoding(XML_Parser p, 24075bb6a25fSPoul-Henning Kamp const XML_Char *encoding); 24085bb6a25fSPoul-Henning Kamp</pre> 24095bb6a25fSPoul-Henning Kamp<div class="fcndef"> 24105bb6a25fSPoul-Henning KampSet the encoding to be used by the parser. It is equivalent to 24114543ef51SXin LIpassing a non-<code>NULL</code> encoding argument to the parser creation functions. 24125bb6a25fSPoul-Henning KampIt must not be called after <code><a href= "#XML_Parse" 24135bb6a25fSPoul-Henning Kamp>XML_Parse</a></code> or <code><a href= "#XML_ParseBuffer" 24145bb6a25fSPoul-Henning Kamp>XML_ParseBuffer</a></code> have been called on the given parser. 2415220ed979SColeman KaneReturns <code>XML_STATUS_OK</code> on success or 2416220ed979SColeman Kane<code>XML_STATUS_ERROR</code> on error. 24175bb6a25fSPoul-Henning Kamp</div> 24185bb6a25fSPoul-Henning Kamp 2419cc68614dSXin LI<h4 id="XML_SetParamEntityParsing">XML_SetParamEntityParsing</h4> 2420cc68614dSXin LI<pre class="fcndec"> 2421220ed979SColeman Kaneint XMLCALL 24225bb6a25fSPoul-Henning KampXML_SetParamEntityParsing(XML_Parser p, 24235bb6a25fSPoul-Henning Kamp enum XML_ParamEntityParsing code); 24245bb6a25fSPoul-Henning Kamp</pre> 24255bb6a25fSPoul-Henning Kamp<div class="fcndef"> 24265bb6a25fSPoul-Henning KampThis enables parsing of parameter entities, including the external 24275bb6a25fSPoul-Henning Kampparameter entity that is the external DTD subset, according to 24285bb6a25fSPoul-Henning Kamp<code>code</code>. 24295bb6a25fSPoul-Henning KampThe choices for <code>code</code> are: 24305bb6a25fSPoul-Henning Kamp<ul> 24315bb6a25fSPoul-Henning Kamp<li><code>XML_PARAM_ENTITY_PARSING_NEVER</code></li> 24325bb6a25fSPoul-Henning Kamp<li><code>XML_PARAM_ENTITY_PARSING_UNLESS_STANDALONE</code></li> 24335bb6a25fSPoul-Henning Kamp<li><code>XML_PARAM_ENTITY_PARSING_ALWAYS</code></li> 24345bb6a25fSPoul-Henning Kamp</ul> 2435e3466a89SXin LI<b>Note:</b> If <code>XML_SetParamEntityParsing</code> is called after 2436e3466a89SXin LI<code>XML_Parse</code> or <code>XML_ParseBuffer</code>, then it has 2437e3466a89SXin LIno effect and will always return 0. 2438e3466a89SXin LI</div> 2439e3466a89SXin LI 2440cc68614dSXin LI<h4 id="XML_SetHashSalt">XML_SetHashSalt</h4> 2441cc68614dSXin LI<pre class="fcndec"> 2442e3466a89SXin LIint XMLCALL 2443e3466a89SXin LIXML_SetHashSalt(XML_Parser p, 2444e3466a89SXin LI unsigned long hash_salt); 2445e3466a89SXin LI</pre> 2446e3466a89SXin LI<div class="fcndef"> 2447e3466a89SXin LISets the hash salt to use for internal hash calculations. 2448e3466a89SXin LIHelps in preventing DoS attacks based on predicting hash 2449e3466a89SXin LIfunction behavior. In order to have an effect this must be called 2450e3466a89SXin LIbefore parsing has started. Returns 1 if successful, 0 when called 2451e3466a89SXin LIafter <code>XML_Parse</code> or <code>XML_ParseBuffer</code>. 2452be8aff81SXin LI<p><b>Note:</b> This call is optional, as the parser will auto-generate 24536b2c1e49SXin LIa new random salt value if no value has been set at the start of parsing.</p> 2454be8aff81SXin LI<p><b>Note:</b> One should not call <code>XML_SetHashSalt</code> with a 2455be8aff81SXin LIhash salt value of 0, as this value is used as sentinel value to indicate 2456be8aff81SXin LIthat <code>XML_SetHashSalt</code> has <b>not</b> been called. Consequently 2457be8aff81SXin LIsuch a call will have no effect, even if it returns 1.</p> 24585bb6a25fSPoul-Henning Kamp</div> 24595bb6a25fSPoul-Henning Kamp 2460cc68614dSXin LI<h4 id="XML_UseForeignDTD">XML_UseForeignDTD</h4> 2461cc68614dSXin LI<pre class="fcndec"> 2462220ed979SColeman Kaneenum XML_Error XMLCALL 24635bb6a25fSPoul-Henning KampXML_UseForeignDTD(XML_Parser parser, XML_Bool useDTD); 24645bb6a25fSPoul-Henning Kamp</pre> 24655bb6a25fSPoul-Henning Kamp<div class="fcndef"> 24665bb6a25fSPoul-Henning Kamp<p>This function allows an application to provide an external subset 24675bb6a25fSPoul-Henning Kampfor the document type declaration for documents which do not specify 24685bb6a25fSPoul-Henning Kampan external subset of their own. For documents which specify an 24695bb6a25fSPoul-Henning Kampexternal subset in their DOCTYPE declaration, the application-provided 24705bb6a25fSPoul-Henning Kampsubset will be ignored. If the document does not contain a DOCTYPE 24715bb6a25fSPoul-Henning Kampdeclaration at all and <code>useDTD</code> is true, the 24725bb6a25fSPoul-Henning Kampapplication-provided subset will be parsed, but the 24735bb6a25fSPoul-Henning Kamp<code>startDoctypeDeclHandler</code> and 24745bb6a25fSPoul-Henning Kamp<code>endDoctypeDeclHandler</code> functions, if set, will not be 24755bb6a25fSPoul-Henning Kampcalled. The setting of parameter entity parsing, controlled using 24765bb6a25fSPoul-Henning Kamp<code><a href= "#XML_SetParamEntityParsing" 24775bb6a25fSPoul-Henning Kamp>XML_SetParamEntityParsing</a></code>, will be honored.</p> 24785bb6a25fSPoul-Henning Kamp 24795bb6a25fSPoul-Henning Kamp<p>The application-provided external subset is read by calling the 24805bb6a25fSPoul-Henning Kampexternal entity reference handler set via <code><a href= 24815bb6a25fSPoul-Henning Kamp"#XML_SetExternalEntityRefHandler" 24825bb6a25fSPoul-Henning Kamp>XML_SetExternalEntityRefHandler</a></code> with both 24834543ef51SXin LI<code>publicId</code> and <code>systemId</code> set to <code>NULL</code>.</p> 24845bb6a25fSPoul-Henning Kamp 24855bb6a25fSPoul-Henning Kamp<p>If this function is called after parsing has begun, it returns 24865bb6a25fSPoul-Henning Kamp<code>XML_ERROR_CANT_CHANGE_FEATURE_ONCE_PARSING</code> and ignores 24875bb6a25fSPoul-Henning Kamp<code>useDTD</code>. If called when Expat has been compiled without 24885bb6a25fSPoul-Henning KampDTD support, it returns 24895bb6a25fSPoul-Henning Kamp<code>XML_ERROR_FEATURE_REQUIRES_XML_DTD</code>. Otherwise, it 24905bb6a25fSPoul-Henning Kampreturns <code>XML_ERROR_NONE</code>.</p> 2491220ed979SColeman Kane 2492220ed979SColeman Kane<p><b>Note:</b> For the purpose of checking WFC: Entity Declared, passing 2493220ed979SColeman Kane<code>useDTD == XML_TRUE</code> will make the parser behave as if 2494220ed979SColeman Kanethe document had a DTD with an external subset. This holds true even if 2495220ed979SColeman Kanethe external entity reference handler returns without action.</p> 24965bb6a25fSPoul-Henning Kamp</div> 24975bb6a25fSPoul-Henning Kamp 2498cc68614dSXin LI<h4 id="XML_SetReturnNSTriplet">XML_SetReturnNSTriplet</h4> 2499cc68614dSXin LI<pre class="fcndec"> 2500220ed979SColeman Kanevoid XMLCALL 25015bb6a25fSPoul-Henning KampXML_SetReturnNSTriplet(XML_Parser parser, 25025bb6a25fSPoul-Henning Kamp int do_nst); 25035bb6a25fSPoul-Henning Kamp</pre> 25045bb6a25fSPoul-Henning Kamp<div class="fcndef"> 25055bb6a25fSPoul-Henning Kamp<p> 25065bb6a25fSPoul-Henning KampThis function only has an effect when using a parser created with 25075bb6a25fSPoul-Henning Kamp<code><a href= "#XML_ParserCreateNS" >XML_ParserCreateNS</a></code>, 25085bb6a25fSPoul-Henning Kampi.e. when namespace processing is in effect. The <code>do_nst</code> 25095bb6a25fSPoul-Henning Kampsets whether or not prefixes are returned with names qualified with a 25105bb6a25fSPoul-Henning Kampnamespace prefix. If this function is called with <code>do_nst</code> 25115bb6a25fSPoul-Henning Kampnon-zero, then afterwards namespace qualified names (that is qualified 25125bb6a25fSPoul-Henning Kampwith a prefix as opposed to belonging to a default namespace) are 25135bb6a25fSPoul-Henning Kampreturned as a triplet with the three parts separated by the namespace 25145bb6a25fSPoul-Henning Kampseparator specified when the parser was created. The order of 25155bb6a25fSPoul-Henning Kampreturned parts is URI, local name, and prefix.</p> <p>If 25165bb6a25fSPoul-Henning Kamp<code>do_nst</code> is zero, then namespaces are reported in the 25175bb6a25fSPoul-Henning Kampdefault manner, URI then local_name separated by the namespace 25185bb6a25fSPoul-Henning Kampseparator.</p> 25195bb6a25fSPoul-Henning Kamp</div> 25205bb6a25fSPoul-Henning Kamp 2521cc68614dSXin LI<h4 id="XML_DefaultCurrent">XML_DefaultCurrent</h4> 2522cc68614dSXin LI<pre class="fcndec"> 2523220ed979SColeman Kanevoid XMLCALL 25245bb6a25fSPoul-Henning KampXML_DefaultCurrent(XML_Parser parser); 25255bb6a25fSPoul-Henning Kamp</pre> 25265bb6a25fSPoul-Henning Kamp<div class="fcndef"> 25275bb6a25fSPoul-Henning KampThis can be called within a handler for a start element, end element, 25285bb6a25fSPoul-Henning Kampprocessing instruction or character data. It causes the corresponding 25295bb6a25fSPoul-Henning Kampmarkup to be passed to the default handler set by <code><a 25305bb6a25fSPoul-Henning Kamphref="#XML_SetDefaultHandler" >XML_SetDefaultHandler</a></code> or 25315bb6a25fSPoul-Henning Kamp<code><a href="#XML_SetDefaultHandlerExpand" 25325bb6a25fSPoul-Henning Kamp>XML_SetDefaultHandlerExpand</a></code>. It does nothing if there is 25335bb6a25fSPoul-Henning Kampnot a default handler. 25345bb6a25fSPoul-Henning Kamp</div> 25355bb6a25fSPoul-Henning Kamp 2536cc68614dSXin LI<h4 id="XML_ExpatVersion">XML_ExpatVersion</h4> 2537cc68614dSXin LI<pre class="fcndec"> 2538220ed979SColeman KaneXML_LChar * XMLCALL 25395bb6a25fSPoul-Henning KampXML_ExpatVersion(); 25405bb6a25fSPoul-Henning Kamp</pre> 25415bb6a25fSPoul-Henning Kamp<div class="fcndef"> 25425bb6a25fSPoul-Henning KampReturn the library version as a string (e.g. <code>"expat_1.95.1"</code>). 25435bb6a25fSPoul-Henning Kamp</div> 25445bb6a25fSPoul-Henning Kamp 2545cc68614dSXin LI<h4 id="XML_ExpatVersionInfo">XML_ExpatVersionInfo</h4> 2546cc68614dSXin LI<pre class="fcndec"> 2547220ed979SColeman Kanestruct XML_Expat_Version XMLCALL 25485bb6a25fSPoul-Henning KampXML_ExpatVersionInfo(); 25495bb6a25fSPoul-Henning Kamp</pre> 25505bb6a25fSPoul-Henning Kamp<pre class="signature"> 25515bb6a25fSPoul-Henning Kamptypedef struct { 25525bb6a25fSPoul-Henning Kamp int major; 25535bb6a25fSPoul-Henning Kamp int minor; 25545bb6a25fSPoul-Henning Kamp int micro; 25555bb6a25fSPoul-Henning Kamp} XML_Expat_Version; 25565bb6a25fSPoul-Henning Kamp</pre> 25575bb6a25fSPoul-Henning Kamp<div class="fcndef"> 25585bb6a25fSPoul-Henning KampReturn the library version information as a structure. 25595bb6a25fSPoul-Henning KampSome macros are also defined that support compile-time tests of the 25605bb6a25fSPoul-Henning Kamplibrary version: 25615bb6a25fSPoul-Henning Kamp<ul> 25625bb6a25fSPoul-Henning Kamp<li><code>XML_MAJOR_VERSION</code></li> 25635bb6a25fSPoul-Henning Kamp<li><code>XML_MINOR_VERSION</code></li> 25645bb6a25fSPoul-Henning Kamp<li><code>XML_MICRO_VERSION</code></li> 25655bb6a25fSPoul-Henning Kamp</ul> 25665bb6a25fSPoul-Henning KampTesting these constants is currently the best way to determine if 25675bb6a25fSPoul-Henning Kampparticular parts of the Expat API are available. 25685bb6a25fSPoul-Henning Kamp</div> 25695bb6a25fSPoul-Henning Kamp 2570cc68614dSXin LI<h4 id="XML_GetFeatureList">XML_GetFeatureList</h4> 2571cc68614dSXin LI<pre class="fcndec"> 2572220ed979SColeman Kaneconst XML_Feature * XMLCALL 25735bb6a25fSPoul-Henning KampXML_GetFeatureList(); 25745bb6a25fSPoul-Henning Kamp</pre> 25755bb6a25fSPoul-Henning Kamp<pre class="signature"> 25765bb6a25fSPoul-Henning Kampenum XML_FeatureEnum { 25775bb6a25fSPoul-Henning Kamp XML_FEATURE_END = 0, 25785bb6a25fSPoul-Henning Kamp XML_FEATURE_UNICODE, 25795bb6a25fSPoul-Henning Kamp XML_FEATURE_UNICODE_WCHAR_T, 25805bb6a25fSPoul-Henning Kamp XML_FEATURE_DTD, 25815bb6a25fSPoul-Henning Kamp XML_FEATURE_CONTEXT_BYTES, 25825bb6a25fSPoul-Henning Kamp XML_FEATURE_MIN_SIZE, 25835bb6a25fSPoul-Henning Kamp XML_FEATURE_SIZEOF_XML_CHAR, 2584220ed979SColeman Kane XML_FEATURE_SIZEOF_XML_LCHAR, 2585220ed979SColeman Kane XML_FEATURE_NS, 2586220ed979SColeman Kane XML_FEATURE_LARGE_SIZE 25875bb6a25fSPoul-Henning Kamp}; 25885bb6a25fSPoul-Henning Kamp 25895bb6a25fSPoul-Henning Kamptypedef struct { 25905bb6a25fSPoul-Henning Kamp enum XML_FeatureEnum feature; 25915bb6a25fSPoul-Henning Kamp XML_LChar *name; 25925bb6a25fSPoul-Henning Kamp long int value; 25935bb6a25fSPoul-Henning Kamp} XML_Feature; 25945bb6a25fSPoul-Henning Kamp</pre> 25955bb6a25fSPoul-Henning Kamp<div class="fcndef"> 25965bb6a25fSPoul-Henning Kamp<p>Returns a list of "feature" records, providing details on how 25975bb6a25fSPoul-Henning KampExpat was configured at compile time. Most applications should not 25985bb6a25fSPoul-Henning Kampneed to worry about this, but this information is otherwise not 25995bb6a25fSPoul-Henning Kampavailable from Expat. This function allows code that does need to 26005bb6a25fSPoul-Henning Kampcheck these features to do so at runtime.</p> 26015bb6a25fSPoul-Henning Kamp 26025bb6a25fSPoul-Henning Kamp<p>The return value is an array of <code>XML_Feature</code>, 26035bb6a25fSPoul-Henning Kampterminated by a record with a <code>feature</code> of 26044543ef51SXin LI<code>XML_FEATURE_END</code> and <code>name</code> of <code>NULL</code>, 26055bb6a25fSPoul-Henning Kampidentifying the feature-test macros Expat was compiled with. Since an 26065bb6a25fSPoul-Henning Kampapplication that requires this kind of information needs to determine 26075bb6a25fSPoul-Henning Kampthe type of character the <code>name</code> points to, records for the 26085bb6a25fSPoul-Henning Kamp<code>XML_FEATURE_SIZEOF_XML_CHAR</code> and 26095bb6a25fSPoul-Henning Kamp<code>XML_FEATURE_SIZEOF_XML_LCHAR</code> will be located at the 26105bb6a25fSPoul-Henning Kampbeginning of the list, followed by <code>XML_FEATURE_UNICODE</code> 26115bb6a25fSPoul-Henning Kampand <code>XML_FEATURE_UNICODE_WCHAR_T</code>, if they are present at 26125bb6a25fSPoul-Henning Kampall.</p> 26135bb6a25fSPoul-Henning Kamp 26145bb6a25fSPoul-Henning Kamp<p>Some features have an associated value. If there isn't an 26155bb6a25fSPoul-Henning Kampassociated value, the <code>value</code> field is set to 0. At this 26165bb6a25fSPoul-Henning Kamptime, the following features have been defined to have values:</p> 26175bb6a25fSPoul-Henning Kamp 26185bb6a25fSPoul-Henning Kamp<dl> 26195bb6a25fSPoul-Henning Kamp <dt><code>XML_FEATURE_SIZEOF_XML_CHAR</code></dt> 26205bb6a25fSPoul-Henning Kamp <dd>The number of bytes occupied by one <code>XML_Char</code> 26215bb6a25fSPoul-Henning Kamp character.</dd> 26225bb6a25fSPoul-Henning Kamp <dt><code>XML_FEATURE_SIZEOF_XML_LCHAR</code></dt> 26235bb6a25fSPoul-Henning Kamp <dd>The number of bytes occupied by one <code>XML_LChar</code> 26245bb6a25fSPoul-Henning Kamp character.</dd> 26255bb6a25fSPoul-Henning Kamp <dt><code>XML_FEATURE_CONTEXT_BYTES</code></dt> 26265bb6a25fSPoul-Henning Kamp <dd>The maximum number of characters of context which can be 26275bb6a25fSPoul-Henning Kamp reported by <code><a href= "#XML_GetInputContext" 26285bb6a25fSPoul-Henning Kamp >XML_GetInputContext</a></code>.</dd> 26295bb6a25fSPoul-Henning Kamp</dl> 26305bb6a25fSPoul-Henning Kamp</div> 26315bb6a25fSPoul-Henning Kamp 2632cc68614dSXin LI<h4 id="XML_FreeContentModel">XML_FreeContentModel</h4> 2633cc68614dSXin LI<pre class="fcndec"> 2634220ed979SColeman Kanevoid XMLCALL 2635220ed979SColeman KaneXML_FreeContentModel(XML_Parser parser, XML_Content *model); 2636220ed979SColeman Kane</pre> 2637220ed979SColeman Kane<div class="fcndef"> 2638220ed979SColeman KaneFunction to deallocate the <code>model</code> argument passed to the 2639220ed979SColeman Kane<code>XML_ElementDeclHandler</code> callback set using <code><a 2640220ed979SColeman Kanehref="#XML_SetElementDeclHandler" >XML_ElementDeclHandler</a></code>. 2641220ed979SColeman KaneThis function should not be used for any other purpose. 2642220ed979SColeman Kane</div> 2643220ed979SColeman Kane 2644220ed979SColeman Kane<p>The following functions allow external code to share the memory 2645220ed979SColeman Kaneallocator an <code>XML_Parser</code> has been configured to use. This 2646220ed979SColeman Kaneis especially useful for third-party libraries that interact with a 2647220ed979SColeman Kaneparser object created by application code, or heavily layered 2648220ed979SColeman Kaneapplications. This can be essential when using dynamically loaded 2649220ed979SColeman Kanelibraries which use different C standard libraries (this can happen on 2650220ed979SColeman KaneWindows, at least).</p> 2651220ed979SColeman Kane 2652cc68614dSXin LI<h4 id="XML_MemMalloc">XML_MemMalloc</h4> 2653cc68614dSXin LI<pre class="fcndec"> 2654220ed979SColeman Kanevoid * XMLCALL 2655220ed979SColeman KaneXML_MemMalloc(XML_Parser parser, size_t size); 2656220ed979SColeman Kane</pre> 2657220ed979SColeman Kane<div class="fcndef"> 2658220ed979SColeman KaneAllocate <code>size</code> bytes of memory using the allocator the 2659220ed979SColeman Kane<code>parser</code> object has been configured to use. Returns a 26604543ef51SXin LIpointer to the memory or <code>NULL</code> on failure. Memory allocated in this 2661220ed979SColeman Kaneway must be freed using <code><a href="#XML_MemFree" 2662220ed979SColeman Kane>XML_MemFree</a></code>. 2663220ed979SColeman Kane</div> 2664220ed979SColeman Kane 2665cc68614dSXin LI<h4 id="XML_MemRealloc">XML_MemRealloc</h4> 2666cc68614dSXin LI<pre class="fcndec"> 2667220ed979SColeman Kanevoid * XMLCALL 2668220ed979SColeman KaneXML_MemRealloc(XML_Parser parser, void *ptr, size_t size); 2669220ed979SColeman Kane</pre> 2670220ed979SColeman Kane<div class="fcndef"> 2671220ed979SColeman KaneAllocate <code>size</code> bytes of memory using the allocator the 2672220ed979SColeman Kane<code>parser</code> object has been configured to use. 2673220ed979SColeman Kane<code>ptr</code> must point to a block of memory allocated by <code><a 2674220ed979SColeman Kanehref="#XML_MemMalloc" >XML_MemMalloc</a></code> or 26754543ef51SXin LI<code>XML_MemRealloc</code>, or be <code>NULL</code>. This function tries to 2676220ed979SColeman Kaneexpand the block pointed to by <code>ptr</code> if possible. Returns 26774543ef51SXin LIa pointer to the memory or <code>NULL</code> on failure. On success, the original 2678220ed979SColeman Kaneblock has either been expanded or freed. On failure, the original 2679220ed979SColeman Kaneblock has not been freed; the caller is responsible for freeing the 2680220ed979SColeman Kaneoriginal block. Memory allocated in this way must be freed using 2681220ed979SColeman Kane<code><a href="#XML_MemFree" 2682220ed979SColeman Kane>XML_MemFree</a></code>. 2683220ed979SColeman Kane</div> 2684220ed979SColeman Kane 2685cc68614dSXin LI<h4 id="XML_MemFree">XML_MemFree</h4> 2686cc68614dSXin LI<pre class="fcndec"> 2687220ed979SColeman Kanevoid XMLCALL 2688220ed979SColeman KaneXML_MemFree(XML_Parser parser, void *ptr); 2689220ed979SColeman Kane</pre> 2690220ed979SColeman Kane<div class="fcndef"> 2691220ed979SColeman KaneFree a block of memory pointed to by <code>ptr</code>. The block must 2692220ed979SColeman Kanehave been allocated by <code><a href="#XML_MemMalloc" 26934543ef51SXin LI>XML_MemMalloc</a></code> or <code>XML_MemRealloc</code>, or be <code>NULL</code>. 2694220ed979SColeman Kane</div> 2695220ed979SColeman Kane 26965bb6a25fSPoul-Henning Kamp<hr /> 2697cc68614dSXin LI 2698cc68614dSXin LI <div class="footer"> 2699cc68614dSXin LI Found a bug in the documentation? 2700cc68614dSXin LI <a href="https://github.com/libexpat/libexpat/issues">Please file a bug report.</a> 2701cc68614dSXin LI </div> 2702cc68614dSXin LI 2703220ed979SColeman Kane</div> 27045bb6a25fSPoul-Henning Kamp</body> 27055bb6a25fSPoul-Henning Kamp</html> 2706
