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The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	1	<?xml version="1.0" encoding="iso-8859-1"?>
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Elliott Hughes	33bf975	2021-08-10 17:33:34 -0700	[diff] [blame]	6	<!--
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				14	Copyright (c) 2000 Clark Cooper <coopercc@users.sourceforge.net>
				15	Copyright (c) 2000-2004 Fred L. Drake, Jr. <fdrake@users.sourceforge.net>
				16	Copyright (c) 2002-2012 Karl Waclawek <karl@waclawek.net>
				17	Copyright (c) 2017-2021 Sebastian Pipping <sebastian@pipping.org>
				18	Copyright (c) 2017 Jakub Wilk <jwilk@jwilk.net>
				19	Copyright (c) 2021 Tomas Korbar <tkorbar@redhat.com>
				20	Licensed under the MIT license:
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The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	41	<title>Expat XML Parser</title>
				42	<meta name="author" content="Clark Cooper, coopercc@netheaven.com" />
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Elliott Hughes	33bf975	2021-08-10 17:33:34 -0700	[diff] [blame]	44	<link href="ok.min.css" rel="stylesheet" type="text/css" />
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	45	<link href="style.css" rel="stylesheet" type="text/css" />
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				47	<body>
Elliott Hughes	33bf975	2021-08-10 17:33:34 -0700	[diff] [blame]	48	<div>
				49	<h1>
				50	The Expat XML Parser
				51	<small>Release 2.4.1</small>
				52	</h1>
				53	</div>
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	54	<div class="content">
				55
				56	<p>Expat is a library, written in C, for parsing XML documents. It's
				57	the underlying XML parser for the open source Mozilla project, Perl's
				58	<code>XML::Parser</code>, Python's <code>xml.parsers.expat</code>, and
				59	other open-source XML parsers.</p>
				60
				61	<p>This library is the creation of James Clark, who's also given us
Elliott Hughes	7247294	2018-01-10 08:36:10 -0800	[diff] [blame]	62	groff (an nroff look-alike), Jade (an implementation of ISO's DSSSL
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	63	stylesheet language for SGML), XP (a Java XML parser package), XT (a
				64	Java XSL engine). James was also the technical lead on the XML
				65	Working Group at W3C that produced the XML specification.</p>
				66
				67	<p>This is free software, licensed under the <a
				68	href="../COPYING">MIT/X Consortium license</a>. You may download it
				69	from <a href="http://www.libexpat.org/">the Expat home page</a>.
				70	</p>
				71
				72	<p>The bulk of this document was originally commissioned as an article
				73	by <a href="http://www.xml.com/">XML.com</a>. They graciously allowed
				74	Clark Cooper to retain copyright and to distribute it with Expat.
				75	This version has been substantially extended to include documentation
				76	on features which have been added since the original article was
				77	published, and additional information on using the original
				78	interface.</p>
				79
				80	<hr />
				81	<h2>Table of Contents</h2>
				82	<ul>
				83	<li><a href="#overview">Overview</a></li>
				84	<li><a href="#building">Building and Installing</a></li>
				85	<li><a href="#using">Using Expat</a></li>
				86	<li><a href="#reference">Reference</a>
				87	<ul>
				88	<li><a href="#creation">Parser Creation Functions</a>
				89	<ul>
				90	<li><a href="#XML_ParserCreate">XML_ParserCreate</a></li>
				91	<li><a href="#XML_ParserCreateNS">XML_ParserCreateNS</a></li>
				92	<li><a href="#XML_ParserCreate_MM">XML_ParserCreate_MM</a></li>
				93	<li><a href="#XML_ExternalEntityParserCreate">XML_ExternalEntityParserCreate</a></li>
				94	<li><a href="#XML_ParserFree">XML_ParserFree</a></li>
				95	<li><a href="#XML_ParserReset">XML_ParserReset</a></li>
				96	</ul>
				97	</li>
				98	<li><a href="#parsing">Parsing Functions</a>
				99	<ul>
				100	<li><a href="#XML_Parse">XML_Parse</a></li>
				101	<li><a href="#XML_ParseBuffer">XML_ParseBuffer</a></li>
				102	<li><a href="#XML_GetBuffer">XML_GetBuffer</a></li>
				103	<li><a href="#XML_StopParser">XML_StopParser</a></li>
				104	<li><a href="#XML_ResumeParser">XML_ResumeParser</a></li>
				105	<li><a href="#XML_GetParsingStatus">XML_GetParsingStatus</a></li>
				106	</ul>
				107	</li>
				108	<li><a href="#setting">Handler Setting Functions</a>
				109	<ul>
				110	<li><a href="#XML_SetStartElementHandler">XML_SetStartElementHandler</a></li>
				111	<li><a href="#XML_SetEndElementHandler">XML_SetEndElementHandler</a></li>
				112	<li><a href="#XML_SetElementHandler">XML_SetElementHandler</a></li>
				113	<li><a href="#XML_SetCharacterDataHandler">XML_SetCharacterDataHandler</a></li>
				114	<li><a href="#XML_SetProcessingInstructionHandler">XML_SetProcessingInstructionHandler</a></li>
				115	<li><a href="#XML_SetCommentHandler">XML_SetCommentHandler</a></li>
				116	<li><a href="#XML_SetStartCdataSectionHandler">XML_SetStartCdataSectionHandler</a></li>
				117	<li><a href="#XML_SetEndCdataSectionHandler">XML_SetEndCdataSectionHandler</a></li>
				118	<li><a href="#XML_SetCdataSectionHandler">XML_SetCdataSectionHandler</a></li>
				119	<li><a href="#XML_SetDefaultHandler">XML_SetDefaultHandler</a></li>
				120	<li><a href="#XML_SetDefaultHandlerExpand">XML_SetDefaultHandlerExpand</a></li>
				121	<li><a href="#XML_SetExternalEntityRefHandler">XML_SetExternalEntityRefHandler</a></li>
				122	<li><a href="#XML_SetExternalEntityRefHandlerArg">XML_SetExternalEntityRefHandlerArg</a></li>
				123	<li><a href="#XML_SetSkippedEntityHandler">XML_SetSkippedEntityHandler</a></li>
				124	<li><a href="#XML_SetUnknownEncodingHandler">XML_SetUnknownEncodingHandler</a></li>
				125	<li><a href="#XML_SetStartNamespaceDeclHandler">XML_SetStartNamespaceDeclHandler</a></li>
				126	<li><a href="#XML_SetEndNamespaceDeclHandler">XML_SetEndNamespaceDeclHandler</a></li>
				127	<li><a href="#XML_SetNamespaceDeclHandler">XML_SetNamespaceDeclHandler</a></li>
				128	<li><a href="#XML_SetXmlDeclHandler">XML_SetXmlDeclHandler</a></li>
				129	<li><a href="#XML_SetStartDoctypeDeclHandler">XML_SetStartDoctypeDeclHandler</a></li>
				130	<li><a href="#XML_SetEndDoctypeDeclHandler">XML_SetEndDoctypeDeclHandler</a></li>
				131	<li><a href="#XML_SetDoctypeDeclHandler">XML_SetDoctypeDeclHandler</a></li>
				132	<li><a href="#XML_SetElementDeclHandler">XML_SetElementDeclHandler</a></li>
				133	<li><a href="#XML_SetAttlistDeclHandler">XML_SetAttlistDeclHandler</a></li>
				134	<li><a href="#XML_SetEntityDeclHandler">XML_SetEntityDeclHandler</a></li>
				135	<li><a href="#XML_SetUnparsedEntityDeclHandler">XML_SetUnparsedEntityDeclHandler</a></li>
				136	<li><a href="#XML_SetNotationDeclHandler">XML_SetNotationDeclHandler</a></li>
				137	<li><a href="#XML_SetNotStandaloneHandler">XML_SetNotStandaloneHandler</a></li>
				138	</ul>
				139	</li>
				140	<li><a href="#position">Parse Position and Error Reporting Functions</a>
				141	<ul>
				142	<li><a href="#XML_GetErrorCode">XML_GetErrorCode</a></li>
				143	<li><a href="#XML_ErrorString">XML_ErrorString</a></li>
				144	<li><a href="#XML_GetCurrentByteIndex">XML_GetCurrentByteIndex</a></li>
				145	<li><a href="#XML_GetCurrentLineNumber">XML_GetCurrentLineNumber</a></li>
				146	<li><a href="#XML_GetCurrentColumnNumber">XML_GetCurrentColumnNumber</a></li>
				147	<li><a href="#XML_GetCurrentByteCount">XML_GetCurrentByteCount</a></li>
				148	<li><a href="#XML_GetInputContext">XML_GetInputContext</a></li>
				149	</ul>
				150	</li>
Elliott Hughes	33bf975	2021-08-10 17:33:34 -0700	[diff] [blame]	151	<li>
				152	<a href="#billion-laughs">Billion Laughs Attack Protection</a>
				153	<ul>
				154	<li><a href="#XML_SetBillionLaughsAttackProtectionMaximumAmplification">XML_SetBillionLaughsAttackProtectionMaximumAmplification</a></li>
				155	<li><a href="#XML_SetBillionLaughsAttackProtectionActivationThreshold">XML_SetBillionLaughsAttackProtectionActivationThreshold</a></li>
				156	</ul>
				157	</li>
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	158	<li><a href="#miscellaneous">Miscellaneous Functions</a>
				159	<ul>
				160	<li><a href="#XML_SetUserData">XML_SetUserData</a></li>
				161	<li><a href="#XML_GetUserData">XML_GetUserData</a></li>
				162	<li><a href="#XML_UseParserAsHandlerArg">XML_UseParserAsHandlerArg</a></li>
				163	<li><a href="#XML_SetBase">XML_SetBase</a></li>
				164	<li><a href="#XML_GetBase">XML_GetBase</a></li>
				165	<li><a href="#XML_GetSpecifiedAttributeCount">XML_GetSpecifiedAttributeCount</a></li>
				166	<li><a href="#XML_GetIdAttributeIndex">XML_GetIdAttributeIndex</a></li>
Elliott Hughes	35e432d	2012-09-09 14:23:38 -0700	[diff] [blame]	167	<li><a href="#XML_GetAttributeInfo">XML_GetAttributeInfo</a></li>
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	168	<li><a href="#XML_SetEncoding">XML_SetEncoding</a></li>
				169	<li><a href="#XML_SetParamEntityParsing">XML_SetParamEntityParsing</a></li>
Elliott Hughes	35e432d	2012-09-09 14:23:38 -0700	[diff] [blame]	170	<li><a href="#XML_SetHashSalt">XML_SetHashSalt</a></li>
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	171	<li><a href="#XML_UseForeignDTD">XML_UseForeignDTD</a></li>
				172	<li><a href="#XML_SetReturnNSTriplet">XML_SetReturnNSTriplet</a></li>
				173	<li><a href="#XML_DefaultCurrent">XML_DefaultCurrent</a></li>
				174	<li><a href="#XML_ExpatVersion">XML_ExpatVersion</a></li>
				175	<li><a href="#XML_ExpatVersionInfo">XML_ExpatVersionInfo</a></li>
				176	<li><a href="#XML_GetFeatureList">XML_GetFeatureList</a></li>
				177	<li><a href="#XML_FreeContentModel">XML_FreeContentModel</a></li>
				178	<li><a href="#XML_MemMalloc">XML_MemMalloc</a></li>
				179	<li><a href="#XML_MemRealloc">XML_MemRealloc</a></li>
				180	<li><a href="#XML_MemFree">XML_MemFree</a></li>
				181	</ul>
				182	</li>
				183	</ul>
				184	</li>
				185	</ul>
				186
				187	<hr />
				188	<h2><a name="overview">Overview</a></h2>
				189
				190	<p>Expat is a stream-oriented parser. You register callback (or
				191	handler) functions with the parser and then start feeding it the
				192	document. As the parser recognizes parts of the document, it will
				193	call the appropriate handler for that part (if you've registered one.)
				194	The document is fed to the parser in pieces, so you can start parsing
				195	before you have all the document. This also allows you to parse really
				196	huge documents that won't fit into memory.</p>
				197
				198	<p>Expat can be intimidating due to the many kinds of handlers and
				199	options you can set. But you only need to learn four functions in
				200	order to do 90% of what you'll want to do with it:</p>
				201
				202	<dl>
				203
				204	<dt><code><a href= "#XML_ParserCreate"
				205	>XML_ParserCreate</a></code></dt>
				206	<dd>Create a new parser object.</dd>
				207
				208	<dt><code><a href= "#XML_SetElementHandler"
				209	>XML_SetElementHandler</a></code></dt>
				210	<dd>Set handlers for start and end tags.</dd>
				211
				212	<dt><code><a href= "#XML_SetCharacterDataHandler"
				213	>XML_SetCharacterDataHandler</a></code></dt>
				214	<dd>Set handler for text.</dd>
				215
				216	<dt><code><a href= "#XML_Parse"
				217	>XML_Parse</a></code></dt>
				218	<dd>Pass a buffer full of document to the parser</dd>
				219	</dl>
				220
				221	<p>These functions and others are described in the <a
				222	href="#reference">reference</a> part of this document. The reference
				223	section also describes in detail the parameters passed to the
				224	different types of handlers.</p>
				225
				226	<p>Let's look at a very simple example program that only uses 3 of the
				227	above functions (it doesn't need to set a character handler.) The
				228	program <a href="../examples/outline.c">outline.c</a> prints an
				229	element outline, indenting child elements to distinguish them from the
				230	parent element that contains them. The start handler does all the
				231	work. It prints two indenting spaces for every level of ancestor
				232	elements, then it prints the element and attribute
				233	information. Finally it increments the global <code>Depth</code>
				234	variable.</p>
				235
				236	<pre class="eg">
				237	int Depth;
				238
				239	void XMLCALL
				240	start(void data, const char el, const char **attr) {
				241	int i;
				242
				243	for (i = 0; i < Depth; i++)
				244	printf(" ");
				245
				246	printf("%s", el);
				247
				248	for (i = 0; attr[i]; i += 2) {
				249	printf(" %s='%s'", attr[i], attr[i + 1]);
				250	}
				251
				252	printf("\n");
				253	Depth++;
				254	} /* End of start handler */
				255	</pre>
				256
				257	<p>The end tag simply does the bookkeeping work of decrementing
				258	<code>Depth</code>.</p>
				259	<pre class="eg">
				260	void XMLCALL
				261	end(void data, const char el) {
				262	Depth--;
				263	} /* End of end handler */
				264	</pre>
				265
				266	<p>Note the <code>XMLCALL</code> annotation used for the callbacks.
				267	This is used to ensure that the Expat and the callbacks are using the
				268	same calling convention in case the compiler options used for Expat
				269	itself and the client code are different. Expat tries not to care
				270	what the default calling convention is, though it may require that it
				271	be compiled with a default convention of "cdecl" on some platforms.
				272	For code which uses Expat, however, the calling convention is
				273	specified by the <code>XMLCALL</code> annotation on most platforms;
				274	callbacks should be defined using this annotation.</p>
				275
				276	<p>The <code>XMLCALL</code> annotation was added in Expat 1.95.7, but
				277	existing working Expat applications don't need to add it (since they
				278	are already using the "cdecl" calling convention, or they wouldn't be
				279	working). The annotation is only needed if the default calling
				280	convention may be something other than "cdecl". To use the annotation
				281	safely with older versions of Expat, you can conditionally define it
				282	<em>after</em> including Expat's header file:</p>
				283
				284	<pre class="eg">
				285	#include <expat.h>
				286
				287	#ifndef XMLCALL
				288	#if defined(_MSC_EXTENSIONS) && !defined(__BEOS__) && !defined(__CYGWIN__)
				289	#define XMLCALL __cdecl
				290	#elif defined(__GNUC__)
				291	#define XMLCALL __attribute__((cdecl))
				292	#else
				293	#define XMLCALL
				294	#endif
				295	#endif
				296	</pre>
				297
				298	<p>After creating the parser, the main program just has the job of
				299	shoveling the document to the parser so that it can do its work.</p>
				300
				301	<hr />
				302	<h2><a name="building">Building and Installing Expat</a></h2>
				303
				304	<p>The Expat distribution comes as a compressed (with GNU gzip) tar
				305	file. You may download the latest version from <a href=
				306	"http://sourceforge.net/projects/expat/" >Source Forge</a>. After
				307	unpacking this, cd into the directory. Then follow either the Win32
				308	directions or Unix directions below.</p>
				309
				310	<h3>Building under Win32</h3>
				311
				312	<p>If you're using the GNU compiler under cygwin, follow the Unix
				313	directions in the next section. Otherwise if you have Microsoft's
Haibo Huang	40a7191	2019-10-11 11:13:39 -0700	[diff] [blame]	314	Developer Studio installed,
				315	you can use CMake to generate a <code>.sln</code> file, e.g.
				316	<code>
				317	cmake -G"Visual Studio 15 2017" -DCMAKE_BUILD_TYPE=RelWithDebInfo .
				318	</code>, and build Expat using <code>msbuild /m expat.sln</code> after.</p>
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	319
				320	<p>Alternatively, you may download the Win32 binary package that
				321	contains the "expat.h" include file and a pre-built DLL.</p>
				322
				323	<h3>Building under Unix (or GNU)</h3>
				324
				325	<p>First you'll need to run the configure shell script in order to
				326	configure the Makefiles and headers for your system.</p>
				327
				328	<p>If you're happy with all the defaults that configure picks for you,
				329	and you have permission on your system to install into /usr/local, you
				330	can install Expat with this sequence of commands:</p>
				331
				332	<pre class="eg">
				333	./configure
				334	make
				335	make install
				336	</pre>
				337
				338	<p>There are some options that you can provide to this script, but the
				339	only one we'll mention here is the <code>--prefix</code> option. You
				340	can find out all the options available by running configure with just
				341	the <code>--help</code> option.</p>
				342
				343	<p>By default, the configure script sets things up so that the library
				344	gets installed in <code>/usr/local/lib</code> and the associated
				345	header file in <code>/usr/local/include</code>. But if you were to
				346	give the option, <code>--prefix=/home/me/mystuff</code>, then the
				347	library and header would get installed in
				348	<code>/home/me/mystuff/lib</code> and
				349	<code>/home/me/mystuff/include</code> respectively.</p>
				350
				351	<h3>Configuring Expat Using the Pre-Processor</h3>
				352
				353	<p>Expat's feature set can be configured using a small number of
				354	pre-processor definitions. The definition of this symbols does not
				355	affect the set of entry points for Expat, only the behavior of the API
				356	and the definition of character types in the case of
				357	<code>XML_UNICODE_WCHAR_T</code>. The symbols are:</p>
				358
				359	<dl class="cpp-symbols">
				360	<dt>XML_DTD</dt>
				361	<dd>Include support for using and reporting DTD-based content. If
				362	this is defined, default attribute values from an external DTD subset
				363	are reported and attribute value normalization occurs based on the
				364	type of attributes defined in the external subset. Without
				365	this, Expat has a smaller memory footprint and can be faster, but will
				366	not load external entities or process conditional sections. This does
				367	not affect the set of functions available in the API.</dd>
				368
				369	<dt>XML_NS</dt>
				370	<dd>When defined, support for the <cite><a href=
				371	"http://www.w3.org/TR/REC-xml-names/" >Namespaces in XML</a></cite>
				372	specification is included.</dd>
				373
				374	<dt>XML_UNICODE</dt>
				375	<dd>When defined, character data reported to the application is
				376	encoded in UTF-16 using wide characters of the type
				377	<code>XML_Char</code>. This is implied if
				378	<code>XML_UNICODE_WCHAR_T</code> is defined.</dd>
				379
				380	<dt>XML_UNICODE_WCHAR_T</dt>
				381	<dd>If defined, causes the <code>XML_Char</code> character type to be
				382	defined using the <code>wchar_t</code> type; otherwise, <code>unsigned
				383	short</code> is used. Defining this implies
				384	<code>XML_UNICODE</code>.</dd>
				385
				386	<dt>XML_LARGE_SIZE</dt>
				387	<dd>If defined, causes the <code>XML_Size</code> and <code>XML_Index</code>
				388	integer types to be at least 64 bits in size. This is intended to support
				389	processing of very large input streams, where the return values of
				390	<code><a href="#XML_GetCurrentByteIndex" >XML_GetCurrentByteIndex</a></code>,
				391	<code><a href="#XML_GetCurrentLineNumber" >XML_GetCurrentLineNumber</a></code> and
				392	<code><a href="#XML_GetCurrentColumnNumber" >XML_GetCurrentColumnNumber</a></code>
				393	could overflow. It may not be supported by all compilers, and is turned
				394	off by default.</dd>
				395
				396	<dt>XML_CONTEXT_BYTES</dt>
				397	<dd>The number of input bytes of markup context which the parser will
				398	ensure are available for reporting via <code><a href=
				399	"#XML_GetInputContext" >XML_GetInputContext</a></code>. This is
Elliott Hughes	7247294	2018-01-10 08:36:10 -0800	[diff] [blame]	400	normally set to 1024, and must be set to a positive integer. If this
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	401	is not defined, the input context will not be available and <code><a
				402	href= "#XML_GetInputContext" >XML_GetInputContext</a></code> will
				403	always report NULL. Without this, Expat has a smaller memory
				404	footprint and can be faster.</dd>
				405
				406	<dt>XML_STATIC</dt>
				407	<dd>On Windows, this should be set if Expat is going to be linked
				408	statically with the code that calls it; this is required to get all
				409	the right MSVC magic annotations correct. This is ignored on other
				410	platforms.</dd>
Elliott Hughes	35e432d	2012-09-09 14:23:38 -0700	[diff] [blame]	411
				412	<dt>XML_ATTR_INFO</dt>
Elliott Hughes	7247294	2018-01-10 08:36:10 -0800	[diff] [blame]	413	<dd>If defined, makes the additional function <code><a href=
Elliott Hughes	35e432d	2012-09-09 14:23:38 -0700	[diff] [blame]	414	"#XML_GetAttributeInfo" >XML_GetAttributeInfo</a></code> available
				415	for reporting attribute byte offsets.</dd>
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	416	</dl>
				417
				418	<hr />
				419	<h2><a name="using">Using Expat</a></h2>
				420
				421	<h3>Compiling and Linking Against Expat</h3>
				422
				423	<p>Unless you installed Expat in a location not expected by your
				424	compiler and linker, all you have to do to use Expat in your programs
				425	is to include the Expat header (<code>#include <expat.h></code>)
				426	in your files that make calls to it and to tell the linker that it
				427	needs to link against the Expat library. On Unix systems, this would
				428	usually be done with the <code>-lexpat</code> argument. Otherwise,
				429	you'll need to tell the compiler where to look for the Expat header
				430	and the linker where to find the Expat library. You may also need to
Elliott Hughes	d07d5a7	2009-09-25 16:04:37 -0700	[diff] [blame]	431	take steps to tell the operating system where to find this library at
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	432	run time.</p>
				433
				434	<p>On a Unix-based system, here's what a Makefile might look like when
				435	Expat is installed in a standard location:</p>
				436
				437	<pre class="eg">
				438	CC=cc
				439	LDFLAGS=
				440	LIBS= -lexpat
				441	xmlapp: xmlapp.o
				442	$(CC) $(LDFLAGS) -o xmlapp xmlapp.o $(LIBS)
				443	</pre>
				444
				445	<p>If you installed Expat in, say, <code>/home/me/mystuff</code>, then
				446	the Makefile would look like this:</p>
				447
				448	<pre class="eg">
				449	CC=cc
				450	CFLAGS= -I/home/me/mystuff/include
				451	LDFLAGS=
				452	LIBS= -L/home/me/mystuff/lib -lexpat
				453	xmlapp: xmlapp.o
				454	$(CC) $(LDFLAGS) -o xmlapp xmlapp.o $(LIBS)
				455	</pre>
				456
				457	<p>You'd also have to set the environment variable
				458	<code>LD_LIBRARY_PATH</code> to <code>/home/me/mystuff/lib</code> (or
				459	to <code>${LD_LIBRARY_PATH}:/home/me/mystuff/lib</code> if
				460	LD_LIBRARY_PATH already has some directories in it) in order to run
				461	your application.</p>
				462
				463	<h3>Expat Basics</h3>
				464
				465	<p>As we saw in the example in the overview, the first step in parsing
				466	an XML document with Expat is to create a parser object. There are <a
				467	href="#creation">three functions</a> in the Expat API for creating a
				468	parser object. However, only two of these (<code><a href=
				469	"#XML_ParserCreate" >XML_ParserCreate</a></code> and <code><a href=
				470	"#XML_ParserCreateNS" >XML_ParserCreateNS</a></code>) can be used for
				471	constructing a parser for a top-level document. The object returned
				472	by these functions is an opaque pointer (i.e. "expat.h" declares it as
				473	void *) to data with further internal structure. In order to free the
				474	memory associated with this object you must call <code><a href=
				475	"#XML_ParserFree" >XML_ParserFree</a></code>. Note that if you have
				476	provided any <a href="#userdata">user data</a> that gets stored in the
				477	parser, then your application is responsible for freeing it prior to
				478	calling <code>XML_ParserFree</code>.</p>
				479
				480	<p>The objects returned by the parser creation functions are good for
				481	parsing only one XML document or external parsed entity. If your
				482	application needs to parse many XML documents, then it needs to create
				483	a parser object for each one. The best way to deal with this is to
				484	create a higher level object that contains all the default
				485	initialization you want for your parser objects.</p>
				486
				487	<p>Walking through a document hierarchy with a stream oriented parser
				488	will require a good stack mechanism in order to keep track of current
				489	context. For instance, to answer the simple question, "What element
				490	does this text belong to?" requires a stack, since the parser may have
				491	descended into other elements that are children of the current one and
				492	has encountered this text on the way out.</p>
				493
				494	<p>The things you're likely to want to keep on a stack are the
				495	currently opened element and it's attributes. You push this
				496	information onto the stack in the start handler and you pop it off in
				497	the end handler.</p>
				498
				499	<p>For some tasks, it is sufficient to just keep information on what
				500	the depth of the stack is (or would be if you had one.) The outline
				501	program shown above presents one example. Another such task would be
				502	skipping over a complete element. When you see the start tag for the
				503	element you want to skip, you set a skip flag and record the depth at
				504	which the element started. When the end tag handler encounters the
				505	same depth, the skipped element has ended and the flag may be
				506	cleared. If you follow the convention that the root element starts at
				507	1, then you can use the same variable for skip flag and skip
				508	depth.</p>
				509
				510	<pre class="eg">
				511	void
				512	init_info(Parseinfo *info) {
				513	info->skip = 0;
				514	info->depth = 1;
				515	/* Other initializations here */
				516	} /* End of init_info */
				517
				518	void XMLCALL
				519	rawstart(void data, const char el, const char **attr) {
				520	Parseinfo inf = (Parseinfo ) data;
				521
				522	if (! inf->skip) {
				523	if (should_skip(inf, el, attr)) {
				524	inf->skip = inf->depth;
				525	}
				526	else
				527	start(inf, el, attr); /* This does rest of start handling */
				528	}
				529
				530	inf->depth++;
				531	} /* End of rawstart */
				532
				533	void XMLCALL
				534	rawend(void data, const char el) {
				535	Parseinfo inf = (Parseinfo ) data;
				536
				537	inf->depth--;
				538
				539	if (! inf->skip)
				540	end(inf, el); /* This does rest of end handling */
				541
				542	if (inf->skip == inf->depth)
				543	inf->skip = 0;
				544	} /* End rawend */
				545	</pre>
				546
				547	<p>Notice in the above example the difference in how depth is
				548	manipulated in the start and end handlers. The end tag handler should
				549	be the mirror image of the start tag handler. This is necessary to
				550	properly model containment. Since, in the start tag handler, we
				551	incremented depth <em>after</em> the main body of start tag code, then
				552	in the end handler, we need to manipulate it <em>before</em> the main
				553	body. If we'd decided to increment it first thing in the start
				554	handler, then we'd have had to decrement it last thing in the end
				555	handler.</p>
				556
				557	<h3 id="userdata">Communicating between handlers</h3>
				558
				559	<p>In order to be able to pass information between different handlers
				560	without using globals, you'll need to define a data structure to hold
				561	the shared variables. You can then tell Expat (with the <code><a href=
				562	"#XML_SetUserData" >XML_SetUserData</a></code> function) to pass a
				563	pointer to this structure to the handlers. This is the first
				564	argument received by most handlers. In the <a href="#reference"
				565	>reference section</a>, an argument to a callback function is named
				566	<code>userData</code> and have type <code>void *</code> if the user
				567	data is passed; it will have the type <code>XML_Parser</code> if the
				568	parser itself is passed. When the parser is passed, the user data may
				569	be retrieved using <code><a href="#XML_GetUserData"
				570	>XML_GetUserData</a></code>.</p>
				571
				572	<p>One common case where multiple calls to a single handler may need
				573	to communicate using an application data structure is the case when
				574	content passed to the character data handler (set by <code><a href=
				575	"#XML_SetCharacterDataHandler"
				576	>XML_SetCharacterDataHandler</a></code>) needs to be accumulated. A
				577	common first-time mistake with any of the event-oriented interfaces to
				578	an XML parser is to expect all the text contained in an element to be
				579	reported by a single call to the character data handler. Expat, like
				580	many other XML parsers, reports such data as a sequence of calls;
				581	there's no way to know when the end of the sequence is reached until a
				582	different callback is made. A buffer referenced by the user data
				583	structure proves both an effective and convenient place to accumulate
				584	character data.</p>
				585
				586	<!-- XXX example needed here -->
				587
				588
				589	<h3>XML Version</h3>
				590
				591	<p>Expat is an XML 1.0 parser, and as such never complains based on
				592	the value of the <code>version</code> pseudo-attribute in the XML
				593	declaration, if present.</p>
				594
				595	<p>If an application needs to check the version number (to support
				596	alternate processing), it should use the <code><a href=
				597	"#XML_SetXmlDeclHandler" >XML_SetXmlDeclHandler</a></code> function to
				598	set a handler that uses the information in the XML declaration to
				599	determine what to do. This example shows how to check that only a
				600	version number of <code>"1.0"</code> is accepted:</p>
				601
				602	<pre class="eg">
				603	static int wrong_version;
				604	static XML_Parser parser;
				605
				606	static void XMLCALL
				607	xmldecl_handler(void *userData,
				608	const XML_Char *version,
				609	const XML_Char *encoding,
				610	int standalone)
				611	{
				612	static const XML_Char Version_1_0[] = {'1', '.', '0', 0};
				613
				614	int i;
				615
				616	for (i = 0; i < (sizeof(Version_1_0) / sizeof(Version_1_0[0])); ++i) {
				617	if (version[i] != Version_1_0[i]) {
				618	wrong_version = 1;
				619	/* also clear all other handlers: */
				620	XML_SetCharacterDataHandler(parser, NULL);
				621	...
				622	return;
				623	}
				624	}
				625	...
				626	}
				627	</pre>
				628
				629	<h3>Namespace Processing</h3>
				630
				631	<p>When the parser is created using the <code><a href=
				632	"#XML_ParserCreateNS" >XML_ParserCreateNS</a></code>, function, Expat
				633	performs namespace processing. Under namespace processing, Expat
				634	consumes <code>xmlns</code> and <code>xmlns:...</code> attributes,
				635	which declare namespaces for the scope of the element in which they
				636	occur. This means that your start handler will not see these
				637	attributes. Your application can still be informed of these
				638	declarations by setting namespace declaration handlers with <a href=
				639	"#XML_SetNamespaceDeclHandler"
				640	><code>XML_SetNamespaceDeclHandler</code></a>.</p>
				641
				642	<p>Element type and attribute names that belong to a given namespace
				643	are passed to the appropriate handler in expanded form. By default
				644	this expanded form is a concatenation of the namespace URI, the
				645	separator character (which is the 2nd argument to <code><a href=
				646	"#XML_ParserCreateNS" >XML_ParserCreateNS</a></code>), and the local
				647	name (i.e. the part after the colon). Names with undeclared prefixes
				648	are not well-formed when namespace processing is enabled, and will
				649	trigger an error. Unprefixed attribute names are never expanded,
				650	and unprefixed element names are only expanded when they are in the
				651	scope of a default namespace.</p>
				652
				653	<p>However if <code><a href= "#XML_SetReturnNSTriplet"
				654	>XML_SetReturnNSTriplet</a></code> has been called with a non-zero
				655	<code>do_nst</code> parameter, then the expanded form for names with
				656	an explicit prefix is a concatenation of: URI, separator, local name,
				657	separator, prefix.</p>
				658
				659	<p>You can set handlers for the start of a namespace declaration and
				660	for the end of a scope of a declaration with the <code><a href=
				661	"#XML_SetNamespaceDeclHandler" >XML_SetNamespaceDeclHandler</a></code>
				662	function. The StartNamespaceDeclHandler is called prior to the start
				663	tag handler and the EndNamespaceDeclHandler is called after the
				664	corresponding end tag that ends the namespace's scope. The namespace
				665	start handler gets passed the prefix and URI for the namespace. For a
				666	default namespace declaration (xmlns='...'), the prefix will be null.
				667	The URI will be null for the case where the default namespace is being
				668	unset. The namespace end handler just gets the prefix for the closing
				669	scope.</p>
				670
				671	<p>These handlers are called for each declaration. So if, for
				672	instance, a start tag had three namespace declarations, then the
				673	StartNamespaceDeclHandler would be called three times before the start
				674	tag handler is called, once for each declaration.</p>
				675
				676	<h3>Character Encodings</h3>
				677
				678	<p>While XML is based on Unicode, and every XML processor is required
				679	to recognized UTF-8 and UTF-16 (1 and 2 byte encodings of Unicode),
				680	other encodings may be declared in XML documents or entities. For the
				681	main document, an XML declaration may contain an encoding
				682	declaration:</p>
				683	<pre>
				684	<?xml version="1.0" encoding="ISO-8859-2"?>
				685	</pre>
				686
				687	<p>External parsed entities may begin with a text declaration, which
				688	looks like an XML declaration with just an encoding declaration:</p>
				689	<pre>
				690	<?xml encoding="Big5"?>
				691	</pre>
				692
				693	<p>With Expat, you may also specify an encoding at the time of
				694	creating a parser. This is useful when the encoding information may
				695	come from a source outside the document itself (like a higher level
				696	protocol.)</p>
				697
				698	<p><a name="builtin_encodings"></a>There are four built-in encodings
				699	in Expat:</p>
				700	<ul>
				701	<li>UTF-8</li>
				702	<li>UTF-16</li>
				703	<li>ISO-8859-1</li>
				704	<li>US-ASCII</li>
				705	</ul>
				706
				707	<p>Anything else discovered in an encoding declaration or in the
				708	protocol encoding specified in the parser constructor, triggers a call
				709	to the <code>UnknownEncodingHandler</code>. This handler gets passed
				710	the encoding name and a pointer to an <code>XML_Encoding</code> data
				711	structure. Your handler must fill in this structure and return
				712	<code>XML_STATUS_OK</code> if it knows how to deal with the
				713	encoding. Otherwise the handler should return
				714	<code>XML_STATUS_ERROR</code>. The handler also gets passed a pointer
				715	to an optional application data structure that you may indicate when
				716	you set the handler.</p>
				717
				718	<p>Expat places restrictions on character encodings that it can
				719	support by filling in the <code>XML_Encoding</code> structure.
				720	include file:</p>
				721	<ol>
				722	<li>Every ASCII character that can appear in a well-formed XML document
				723	must be represented by a single byte, and that byte must correspond to
				724	it's ASCII encoding (except for the characters $@\^'{}~)</li>
				725	<li>Characters must be encoded in 4 bytes or less.</li>
				726	<li>All characters encoded must have Unicode scalar values less than or
				727	equal to 65535 (0xFFFF)<em>This does not apply to the built-in support
				728	for UTF-16 and UTF-8</em></li>
				729	<li>No character may be encoded by more that one distinct sequence of
				730	bytes</li>
				731	</ol>
				732
				733	<p><code>XML_Encoding</code> contains an array of integers that
				734	correspond to the 1st byte of an encoding sequence. If the value in
				735	the array for a byte is zero or positive, then the byte is a single
				736	byte encoding that encodes the Unicode scalar value contained in the
				737	array. A -1 in this array indicates a malformed byte. If the value is
				738	-2, -3, or -4, then the byte is the beginning of a 2, 3, or 4 byte
				739	sequence respectively. Multi-byte sequences are sent to the convert
				740	function pointed at in the <code>XML_Encoding</code> structure. This
				741	function should return the Unicode scalar value for the sequence or -1
				742	if the sequence is malformed.</p>
				743
				744	<p>One pitfall that novice Expat users are likely to fall into is that
				745	although Expat may accept input in various encodings, the strings that
				746	it passes to the handlers are always encoded in UTF-8 or UTF-16
				747	(depending on how Expat was compiled). Your application is responsible
				748	for any translation of these strings into other encodings.</p>
				749
				750	<h3>Handling External Entity References</h3>
				751
				752	<p>Expat does not read or parse external entities directly. Note that
				753	any external DTD is a special case of an external entity. If you've
				754	set no <code>ExternalEntityRefHandler</code>, then external entity
				755	references are silently ignored. Otherwise, it calls your handler with
				756	the information needed to read and parse the external entity.</p>
				757
				758	<p>Your handler isn't actually responsible for parsing the entity, but
				759	it is responsible for creating a subsidiary parser with <code><a href=
				760	"#XML_ExternalEntityParserCreate"
				761	>XML_ExternalEntityParserCreate</a></code> that will do the job. This
				762	returns an instance of <code>XML_Parser</code> that has handlers and
				763	other data structures initialized from the parent parser. You may then
				764	use <code><a href= "#XML_Parse" >XML_Parse</a></code> or <code><a
				765	href= "#XML_ParseBuffer">XML_ParseBuffer</a></code> calls against this
				766	parser. Since external entities my refer to other external entities,
				767	your handler should be prepared to be called recursively.</p>
				768
				769	<h3>Parsing DTDs</h3>
				770
				771	<p>In order to parse parameter entities, before starting the parse,
				772	you must call <code><a href= "#XML_SetParamEntityParsing"
				773	>XML_SetParamEntityParsing</a></code> with one of the following
				774	arguments:</p>
				775	<dl>
				776	<dt><code>XML_PARAM_ENTITY_PARSING_NEVER</code></dt>
				777	<dd>Don't parse parameter entities or the external subset</dd>
				778	<dt><code>XML_PARAM_ENTITY_PARSING_UNLESS_STANDALONE</code></dt>
Elliott Hughes	7247294	2018-01-10 08:36:10 -0800	[diff] [blame]	779	<dd>Parse parameter entities and the external subset unless
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	780	<code>standalone</code> was set to "yes" in the XML declaration.</dd>
				781	<dt><code>XML_PARAM_ENTITY_PARSING_ALWAYS</code></dt>
				782	<dd>Always parse parameter entities and the external subset</dd>
				783	</dl>
				784
				785	<p>In order to read an external DTD, you also have to set an external
				786	entity reference handler as described above.</p>
				787
				788	<h3 id="stop-resume">Temporarily Stopping Parsing</h3>
				789
				790	<p>Expat 1.95.8 introduces a new feature: its now possible to stop
				791	parsing temporarily from within a handler function, even if more data
				792	has already been passed into the parser. Applications for this
				793	include</p>
				794
				795	<ul>
				796	<li>Supporting the <a href= "http://www.w3.org/TR/xinclude/"
				797	>XInclude</a> specification.</li>
				798
				799	<li>Delaying further processing until additional information is
				800	available from some other source.</li>
				801
				802	<li>Adjusting processor load as task priorities shift within an
				803	application.</li>
				804
				805	<li>Stopping parsing completely (simply free or reset the parser
				806	instead of resuming in the outer parsing loop). This can be useful
Elliott Hughes	7247294	2018-01-10 08:36:10 -0800	[diff] [blame]	807	if an application-domain error is found in the XML being parsed or if
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	808	the result of the parse is determined not to be useful after
				809	all.</li>
				810	</ul>
				811
				812	<p>To take advantage of this feature, the main parsing loop of an
				813	application needs to support this specifically. It cannot be
				814	supported with a parsing loop compatible with Expat 1.95.7 or
				815	earlier (though existing loops will continue to work without
				816	supporting the stop/resume feature).</p>
				817
				818	<p>An application that uses this feature for a single parser will have
				819	the rough structure (in pseudo-code):</p>
				820
				821	<pre class="pseudocode">
				822	fd = open_input()
				823	p = create_parser()
				824
				825	if parse_xml(p, fd) {
				826	/* suspended */
				827
				828	int suspended = 1;
				829
				830	while (suspended) {
				831	do_something_else()
				832	if ready_to_resume() {
				833	suspended = continue_parsing(p, fd);
				834	}
				835	}
				836	}
				837	</pre>
				838
				839	<p>An application that may resume any of several parsers based on
				840	input (either from the XML being parsed or some other source) will
				841	certainly have more interesting control structures.</p>
				842
				843	<p>This C function could be used for the <code>parse_xml</code>
				844	function mentioned in the pseudo-code above:</p>
				845
				846	<pre class="eg">
				847	#define BUFF_SIZE 10240
				848
				849	/* Parse a document from the open file descriptor 'fd' until the parse
				850	is complete (the document has been completely parsed, or there's
				851	been an error), or the parse is stopped. Return non-zero when
				852	the parse is merely suspended.
				853	*/
				854	int
				855	parse_xml(XML_Parser p, int fd)
				856	{
				857	for (;;) {
				858	int last_chunk;
				859	int bytes_read;
				860	enum XML_Status status;
				861
				862	void *buff = XML_GetBuffer(p, BUFF_SIZE);
				863	if (buff == NULL) {
				864	/* handle error... */
				865	return 0;
				866	}
				867	bytes_read = read(fd, buff, BUFF_SIZE);
				868	if (bytes_read < 0) {
				869	/* handle error... */
				870	return 0;
				871	}
				872	status = XML_ParseBuffer(p, bytes_read, bytes_read == 0);
				873	switch (status) {
				874	case XML_STATUS_ERROR:
				875	/* handle error... */
				876	return 0;
				877	case XML_STATUS_SUSPENDED:
				878	return 1;
				879	}
				880	if (bytes_read == 0)
				881	return 0;
				882	}
				883	}
				884	</pre>
				885
				886	<p>The corresponding <code>continue_parsing</code> function is
				887	somewhat simpler, since it only need deal with the return code from
				888	<code><a href= "#XML_ResumeParser">XML_ResumeParser</a></code>; it can
				889	delegate the input handling to the <code>parse_xml</code>
				890	function:</p>
				891
				892	<pre class="eg">
				893	/* Continue parsing a document which had been suspended. The 'p' and
				894	'fd' arguments are the same as passed to parse_xml(). Return
				895	non-zero when the parse is suspended.
				896	*/
				897	int
				898	continue_parsing(XML_Parser p, int fd)
				899	{
				900	enum XML_Status status = XML_ResumeParser(p);
				901	switch (status) {
				902	case XML_STATUS_ERROR:
				903	/* handle error... */
				904	return 0;
				905	case XML_ERROR_NOT_SUSPENDED:
				906	/* handle error... */
				907	return 0;.
				908	case XML_STATUS_SUSPENDED:
				909	return 1;
				910	}
				911	return parse_xml(p, fd);
				912	}
				913	</pre>
				914
				915	<p>Now that we've seen what a mess the top-level parsing loop can
				916	become, what have we gained? Very simply, we can now use the <code><a
				917	href= "#XML_StopParser" >XML_StopParser</a></code> function to stop
				918	parsing, without having to go to great lengths to avoid additional
				919	processing that we're expecting to ignore. As a bonus, we get to stop
				920	parsing <em>temporarily</em>, and come back to it when we're
				921	ready.</p>
				922
				923	<p>To stop parsing from a handler function, use the <code><a href=
				924	"#XML_StopParser" >XML_StopParser</a></code> function. This function
				925	takes two arguments; the parser being stopped and a flag indicating
				926	whether the parse can be resumed in the future.</p>
				927
				928	<!-- XXX really need more here -->
				929
				930
				931	<hr />
				932	<!-- ================================================================ -->
				933
				934	<h2><a name="reference">Expat Reference</a></h2>
				935
				936	<h3><a name="creation">Parser Creation</a></h3>
				937
Elliott Hughes	33bf975	2021-08-10 17:33:34 -0700	[diff] [blame]	938	<h4 id="XML_ParserCreate">XML_ParserCreate</h4>
				939	<pre class="fcndec">
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	940	XML_Parser XMLCALL
				941	XML_ParserCreate(const XML_Char *encoding);
				942	</pre>
				943	<div class="fcndef">
				944	Construct a new parser. If encoding is non-null, it specifies a
				945	character encoding to use for the document. This overrides the document
				946	encoding declaration. There are four built-in encodings:
				947	<ul>
				948	<li>US-ASCII</li>
				949	<li>UTF-8</li>
				950	<li>UTF-16</li>
				951	<li>ISO-8859-1</li>
				952	</ul>
				953	Any other value will invoke a call to the UnknownEncodingHandler.
				954	</div>
				955
Elliott Hughes	33bf975	2021-08-10 17:33:34 -0700	[diff] [blame]	956	<h4 id="XML_ParserCreateNS">XML_ParserCreateNS</h4>
				957	<pre class="fcndec">
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	958	XML_Parser XMLCALL
				959	XML_ParserCreateNS(const XML_Char *encoding,
				960	XML_Char sep);
				961	</pre>
				962	<div class="fcndef">
				963	Constructs a new parser that has namespace processing in effect. Namespace
				964	expanded element names and attribute names are returned as a concatenation
				965	of the namespace URI, <em>sep</em>, and the local part of the name. This
Elliott Hughes	35e432d	2012-09-09 14:23:38 -0700	[diff] [blame]	966	means that you should pick a character for <em>sep</em> that can't be part
				967	of an URI. Since Expat does not check namespace URIs for conformance, the
				968	only safe choice for a namespace separator is a character that is illegal
				969	in XML. For instance, <code>'\xFF'</code> is not legal in UTF-8, and
				970	<code>'\xFFFF'</code> is not legal in UTF-16. There is a special case when
				971	<em>sep</em> is the null character <code>'\0'</code>: the namespace URI and
				972	the local part will be concatenated without any separator - this is intended
				973	to support RDF processors. It is a programming error to use the null separator
				974	with <a href= "#XML_SetReturnNSTriplet">namespace triplets</a>.</div>
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	975
Elliott Hughes	33bf975	2021-08-10 17:33:34 -0700	[diff] [blame]	976	<h4 id="XML_ParserCreate_MM">XML_ParserCreate_MM</h4>
				977	<pre class="fcndec">
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	978	XML_Parser XMLCALL
				979	XML_ParserCreate_MM(const XML_Char *encoding,
				980	const XML_Memory_Handling_Suite *ms,
				981	const XML_Char *sep);
				982	</pre>
				983	<pre class="signature">
				984	typedef struct {
				985	void (XMLCALL malloc_fcn)(size_t size);
				986	void (XMLCALL realloc_fcn)(void *ptr, size_t size);
				987	void (XMLCALL free_fcn)(void ptr);
				988	} XML_Memory_Handling_Suite;
				989	</pre>
				990	<div class="fcndef">
				991	<p>Construct a new parser using the suite of memory handling functions
				992	specified in <code>ms</code>. If <code>ms</code> is NULL, then use the
				993	standard set of memory management functions. If <code>sep</code> is
				994	non NULL, then namespace processing is enabled in the created parser
				995	and the character pointed at by sep is used as the separator between
				996	the namespace URI and the local part of the name.</p>
				997	</div>
				998
Elliott Hughes	33bf975	2021-08-10 17:33:34 -0700	[diff] [blame]	999	<h4 id="XML_ExternalEntityParserCreate">XML_ExternalEntityParserCreate</h4>
				1000	<pre class="fcndec">
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	1001	XML_Parser XMLCALL
				1002	XML_ExternalEntityParserCreate(XML_Parser p,
				1003	const XML_Char *context,
				1004	const XML_Char *encoding);
				1005	</pre>
				1006	<div class="fcndef">
				1007	Construct a new <code>XML_Parser</code> object for parsing an external
				1008	general entity. Context is the context argument passed in a call to a
				1009	ExternalEntityRefHandler. Other state information such as handlers,
				1010	user data, namespace processing is inherited from the parser passed as
				1011	the 1st argument. So you shouldn't need to call any of the behavior
				1012	changing functions on this parser (unless you want it to act
				1013	differently than the parent parser).
				1014	</div>
				1015
Elliott Hughes	33bf975	2021-08-10 17:33:34 -0700	[diff] [blame]	1016	<h4 id="XML_ParserFree">XML_ParserFree</h4>
				1017	<pre class="fcndec">
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	1018	void XMLCALL
				1019	XML_ParserFree(XML_Parser p);
				1020	</pre>
				1021	<div class="fcndef">
				1022	Free memory used by the parser. Your application is responsible for
				1023	freeing any memory associated with <a href="#userdata">user data</a>.
				1024	</div>
				1025
Elliott Hughes	33bf975	2021-08-10 17:33:34 -0700	[diff] [blame]	1026	<h4 id="XML_ParserReset">XML_ParserReset</h4>
				1027	<pre class="fcndec">
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	1028	XML_Bool XMLCALL
				1029	XML_ParserReset(XML_Parser p,
				1030	const XML_Char *encoding);
				1031	</pre>
				1032	<div class="fcndef">
				1033	Clean up the memory structures maintained by the parser so that it may
				1034	be used again. After this has been called, <code>parser</code> is
				1035	ready to start parsing a new document. All handlers are cleared from
				1036	the parser, except for the unknownEncodingHandler. The parser's external
				1037	state is re-initialized except for the values of ns and ns_triplets.
				1038	This function may not be used on a parser created using <code><a href=
				1039	"#XML_ExternalEntityParserCreate" >XML_ExternalEntityParserCreate</a
				1040	></code>; it will return <code>XML_FALSE</code> in that case. Returns
				1041	<code>XML_TRUE</code> on success. Your application is responsible for
				1042	dealing with any memory associated with <a href="#userdata">user data</a>.
				1043	</div>
				1044
				1045	<h3><a name="parsing">Parsing</a></h3>
				1046
				1047	<p>To state the obvious: the three parsing functions <code><a href=
				1048	"#XML_Parse" >XML_Parse</a></code>, <code><a href= "#XML_ParseBuffer">
				1049	XML_ParseBuffer</a></code> and <code><a href= "#XML_GetBuffer">
				1050	XML_GetBuffer</a></code> must not be called from within a handler
				1051	unless they operate on a separate parser instance, that is, one that
				1052	did not call the handler. For example, it is OK to call the parsing
				1053	functions from within an <code>XML_ExternalEntityRefHandler</code>,
				1054	if they apply to the parser created by
				1055	<code><a href= "#XML_ExternalEntityParserCreate"
				1056	>XML_ExternalEntityParserCreate</a></code>.</p>
				1057
Elliott Hughes	33bf975	2021-08-10 17:33:34 -0700	[diff] [blame]	1058	<p>Note: The <code>len</code> argument passed to these functions
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	1059	should be considerably less than the maximum value for an integer,
				1060	as it could create an integer overflow situation if the added
				1061	lengths of a buffer and the unprocessed portion of the previous buffer
				1062	exceed the maximum integer value. Input data at the end of a buffer
				1063	will remain unprocessed if it is part of an XML token for which the
				1064	end is not part of that buffer.</p>
				1065
Elliott Hughes	33bf975	2021-08-10 17:33:34 -0700	[diff] [blame]	1066	<h4 id="XML_Parse">XML_Parse</h4>
				1067	<pre class="fcndec">
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	1068	enum XML_Status XMLCALL
				1069	XML_Parse(XML_Parser p,
				1070	const char *s,
				1071	int len,
				1072	int isFinal);
				1073	</pre>
				1074	<pre class="signature">
				1075	enum XML_Status {
				1076	XML_STATUS_ERROR = 0,
				1077	XML_STATUS_OK = 1
				1078	};
				1079	</pre>
				1080	<div class="fcndef">
				1081	Parse some more of the document. The string <code>s</code> is a buffer
				1082	containing part (or perhaps all) of the document. The number of bytes of s
				1083	that are part of the document is indicated by <code>len</code>. This means
				1084	that <code>s</code> doesn't have to be null terminated. It also means that
				1085	if <code>len</code> is larger than the number of bytes in the block of
				1086	memory that <code>s</code> points at, then a memory fault is likely. The
				1087	<code>isFinal</code> parameter informs the parser that this is the last
				1088	piece of the document. Frequently, the last piece is empty (i.e.
				1089	<code>len</code> is zero.)
				1090	If a parse error occurred, it returns <code>XML_STATUS_ERROR</code>.
				1091	Otherwise it returns <code>XML_STATUS_OK</code> value.
				1092	</div>
				1093
Elliott Hughes	33bf975	2021-08-10 17:33:34 -0700	[diff] [blame]	1094	<h4 id="XML_ParseBuffer">XML_ParseBuffer</h4>
				1095	<pre class="fcndec">
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	1096	enum XML_Status XMLCALL
				1097	XML_ParseBuffer(XML_Parser p,
				1098	int len,
				1099	int isFinal);
				1100	</pre>
				1101	<div class="fcndef">
				1102	This is just like <code><a href= "#XML_Parse" >XML_Parse</a></code>,
				1103	except in this case Expat provides the buffer. By obtaining the
				1104	buffer from Expat with the <code><a href= "#XML_GetBuffer"
				1105	>XML_GetBuffer</a></code> function, the application can avoid double
				1106	copying of the input.
				1107	</div>
				1108
Elliott Hughes	33bf975	2021-08-10 17:33:34 -0700	[diff] [blame]	1109	<h4 id="XML_GetBuffer">XML_GetBuffer</h4>
				1110	<pre class="fcndec">
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	1111	void * XMLCALL
				1112	XML_GetBuffer(XML_Parser p,
				1113	int len);
				1114	</pre>
				1115	<div class="fcndef">
				1116	Obtain a buffer of size <code>len</code> to read a piece of the document
				1117	into. A NULL value is returned if Expat can't allocate enough memory for
				1118	this buffer. This has to be called prior to every call to
				1119	<code><a href= "#XML_ParseBuffer" >XML_ParseBuffer</a></code>. A
				1120	typical use would look like this:
				1121
				1122	<pre class="eg">
				1123	for (;;) {
				1124	int bytes_read;
				1125	void *buff = XML_GetBuffer(p, BUFF_SIZE);
				1126	if (buff == NULL) {
				1127	/* handle error */
				1128	}
				1129
				1130	bytes_read = read(docfd, buff, BUFF_SIZE);
				1131	if (bytes_read < 0) {
				1132	/* handle error */
				1133	}
				1134
				1135	if (! XML_ParseBuffer(p, bytes_read, bytes_read == 0)) {
				1136	/* handle parse error */
				1137	}
				1138
				1139	if (bytes_read == 0)
				1140	break;
				1141	}
				1142	</pre>
				1143	</div>
				1144
Elliott Hughes	33bf975	2021-08-10 17:33:34 -0700	[diff] [blame]	1145	<h4 id="XML_StopParser">XML_StopParser</h4>
				1146	<pre class="fcndec">
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	1147	enum XML_Status XMLCALL
				1148	XML_StopParser(XML_Parser p,
				1149	XML_Bool resumable);
				1150	</pre>
				1151	<div class="fcndef">
				1152
				1153	<p>Stops parsing, causing <code><a href= "#XML_Parse"
				1154	>XML_Parse</a></code> or <code><a href= "#XML_ParseBuffer"
				1155	>XML_ParseBuffer</a></code> to return. Must be called from within a
				1156	call-back handler, except when aborting (when <code>resumable</code>
				1157	is <code>XML_FALSE</code>) an already suspended parser. Some
				1158	call-backs may still follow because they would otherwise get
Elliott Hughes	33bf975	2021-08-10 17:33:34 -0700	[diff] [blame]	1159	lost, including</p>
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	1160	<ul>
				1161	<li> the end element handler for empty elements when stopped in the
				1162	start element handler,</li>
Elliott Hughes	d07d5a7	2009-09-25 16:04:37 -0700	[diff] [blame]	1163	<li> the end namespace declaration handler when stopped in the end
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	1164	element handler,</li>
Elliott Hughes	d07d5a7	2009-09-25 16:04:37 -0700	[diff] [blame]	1165	<li> the character data handler when stopped in the character data handler
				1166	while making multiple call-backs on a contiguous chunk of characters,</li>
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	1167	</ul>
Elliott Hughes	33bf975	2021-08-10 17:33:34 -0700	[diff] [blame]	1168	<p>and possibly others.</p>
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	1169
				1170	<p>This can be called from most handlers, including DTD related
				1171	call-backs, except when parsing an external parameter entity and
				1172	<code>resumable</code> is <code>XML_TRUE</code>. Returns
				1173	<code>XML_STATUS_OK</code> when successful,
				1174	<code>XML_STATUS_ERROR</code> otherwise. The possible error codes
				1175	are:</p>
				1176	<dl>
				1177	<dt><code>XML_ERROR_SUSPENDED</code></dt>
				1178	<dd>when suspending an already suspended parser.</dd>
				1179	<dt><code>XML_ERROR_FINISHED</code></dt>
				1180	<dd>when the parser has already finished.</dd>
				1181	<dt><code>XML_ERROR_SUSPEND_PE</code></dt>
				1182	<dd>when suspending while parsing an external PE.</dd>
				1183	</dl>
				1184
				1185	<p>Since the stop/resume feature requires application support in the
				1186	outer parsing loop, it is an error to call this function for a parser
				1187	not being handled appropriately; see <a href= "#stop-resume"
				1188	>Temporarily Stopping Parsing</a> for more information.</p>
				1189
				1190	<p>When <code>resumable</code> is <code>XML_TRUE</code> then parsing
				1191	is <em>suspended</em>, that is, <code><a href= "#XML_Parse"
				1192	>XML_Parse</a></code> and <code><a href= "#XML_ParseBuffer"
				1193	>XML_ParseBuffer</a></code> return <code>XML_STATUS_SUSPENDED</code>.
				1194	Otherwise, parsing is <em>aborted</em>, that is, <code><a href=
				1195	"#XML_Parse" >XML_Parse</a></code> and <code><a href=
				1196	"#XML_ParseBuffer" >XML_ParseBuffer</a></code> return
				1197	<code>XML_STATUS_ERROR</code> with error code
				1198	<code>XML_ERROR_ABORTED</code>.</p>
				1199
				1200	<p><strong>Note:</strong>
				1201	This will be applied to the current parser instance only, that is, if
				1202	there is a parent parser then it will continue parsing when the
				1203	external entity reference handler returns. It is up to the
				1204	implementation of that handler to call <code><a href=
				1205	"#XML_StopParser" >XML_StopParser</a></code> on the parent parser
				1206	(recursively), if one wants to stop parsing altogether.</p>
				1207
				1208	<p>When suspended, parsing can be resumed by calling <code><a href=
				1209	"#XML_ResumeParser" >XML_ResumeParser</a></code>.</p>
				1210
				1211	<p>New in Expat 1.95.8.</p>
				1212	</div>
				1213
Elliott Hughes	33bf975	2021-08-10 17:33:34 -0700	[diff] [blame]	1214	<h4 id="XML_ResumeParser">XML_ResumeParser</h4>
				1215	<pre class="fcndec">
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	1216	enum XML_Status XMLCALL
				1217	XML_ResumeParser(XML_Parser p);
				1218	</pre>
				1219	<div class="fcndef">
				1220	<p>Resumes parsing after it has been suspended with <code><a href=
				1221	"#XML_StopParser" >XML_StopParser</a></code>. Must not be called from
				1222	within a handler call-back. Returns same status codes as <code><a
				1223	href= "#XML_Parse">XML_Parse</a></code> or <code><a href=
				1224	"#XML_ParseBuffer" >XML_ParseBuffer</a></code>. An additional error
				1225	code, <code>XML_ERROR_NOT_SUSPENDED</code>, will be returned if the
				1226	parser was not currently suspended.</p>
				1227
				1228	<p><strong>Note:</strong>
				1229	This must be called on the most deeply nested child parser instance
				1230	first, and on its parent parser only after the child parser has
				1231	finished, to be applied recursively until the document entity's parser
				1232	is restarted. That is, the parent parser will not resume by itself
				1233	and it is up to the application to call <code><a href=
				1234	"#XML_ResumeParser" >XML_ResumeParser</a></code> on it at the
				1235	appropriate moment.</p>
				1236
				1237	<p>New in Expat 1.95.8.</p>
				1238	</div>
				1239
Elliott Hughes	33bf975	2021-08-10 17:33:34 -0700	[diff] [blame]	1240	<h4 id="XML_GetParsingStatus">XML_GetParsingStatus</h4>
				1241	<pre class="fcndec">
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	1242	void XMLCALL
				1243	XML_GetParsingStatus(XML_Parser p,
				1244	XML_ParsingStatus *status);
				1245	</pre>
				1246	<pre class="signature">
				1247	enum XML_Parsing {
				1248	XML_INITIALIZED,
				1249	XML_PARSING,
				1250	XML_FINISHED,
				1251	XML_SUSPENDED
				1252	};
				1253
				1254	typedef struct {
				1255	enum XML_Parsing parsing;
				1256	XML_Bool finalBuffer;
				1257	} XML_ParsingStatus;
				1258	</pre>
				1259	<div class="fcndef">
				1260	<p>Returns status of parser with respect to being initialized,
				1261	parsing, finished, or suspended, and whether the final buffer is being
				1262	processed. The <code>status</code> parameter <em>must not</em> be
				1263	NULL.</p>
				1264
				1265	<p>New in Expat 1.95.8.</p>
				1266	</div>
				1267
				1268
				1269	<h3><a name="setting">Handler Setting</a></h3>
				1270
				1271	<p>Although handlers are typically set prior to parsing and left alone, an
				1272	application may choose to set or change the handler for a parsing event
				1273	while the parse is in progress. For instance, your application may choose
				1274	to ignore all text not descended from a <code>para</code> element. One
				1275	way it could do this is to set the character handler when a para start tag
				1276	is seen, and unset it for the corresponding end tag.</p>
				1277
				1278	<p>A handler may be <em>unset</em> by providing a NULL pointer to the
				1279	appropriate handler setter. None of the handler setting functions have
				1280	a return value.</p>
				1281
				1282	<p>Your handlers will be receiving strings in arrays of type
				1283	<code>XML_Char</code>. This type is conditionally defined in expat.h as
				1284	either <code>char</code>, <code>wchar_t</code> or <code>unsigned short</code>.
				1285	The former implies UTF-8 encoding, the latter two imply UTF-16 encoding.
				1286	Note that you'll receive them in this form independent of the original
				1287	encoding of the document.</p>
				1288
				1289	<div class="handler">
Elliott Hughes	33bf975	2021-08-10 17:33:34 -0700	[diff] [blame]	1290	<h4 id="XML_SetStartElementHandler">XML_SetStartElementHandler</h4>
				1291	<pre class="setter">
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	1292	void XMLCALL
				1293	XML_SetStartElementHandler(XML_Parser p,
				1294	XML_StartElementHandler start);
				1295	</pre>
				1296	<pre class="signature">
				1297	typedef void
				1298	(XMLCALL XML_StartElementHandler)(void userData,
				1299	const XML_Char *name,
				1300	const XML_Char **atts);
				1301	</pre>
				1302	<p>Set handler for start (and empty) tags. Attributes are passed to the start
				1303	handler as a pointer to a vector of char pointers. Each attribute seen in
				1304	a start (or empty) tag occupies 2 consecutive places in this vector: the
				1305	attribute name followed by the attribute value. These pairs are terminated
				1306	by a null pointer.</p>
				1307	<p>Note that an empty tag generates a call to both start and end handlers
				1308	(in that order).</p>
				1309	</div>
				1310
				1311	<div class="handler">
Elliott Hughes	33bf975	2021-08-10 17:33:34 -0700	[diff] [blame]	1312	<h4 id="XML_SetEndElementHandler">XML_SetEndElementHandler</h4>
				1313	<pre class="setter">
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	1314	void XMLCALL
				1315	XML_SetEndElementHandler(XML_Parser p,
				1316	XML_EndElementHandler);
				1317	</pre>
				1318	<pre class="signature">
				1319	typedef void
				1320	(XMLCALL XML_EndElementHandler)(void userData,
				1321	const XML_Char *name);
				1322	</pre>
				1323	<p>Set handler for end (and empty) tags. As noted above, an empty tag
				1324	generates a call to both start and end handlers.</p>
				1325	</div>
				1326
				1327	<div class="handler">
Elliott Hughes	33bf975	2021-08-10 17:33:34 -0700	[diff] [blame]	1328	<h4 id="XML_SetElementHandler">XML_SetElementHandler</h4>
				1329	<pre class="setter">
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	1330	void XMLCALL
				1331	XML_SetElementHandler(XML_Parser p,
				1332	XML_StartElementHandler start,
				1333	XML_EndElementHandler end);
				1334	</pre>
				1335	<p>Set handlers for start and end tags with one call.</p>
				1336	</div>
				1337
				1338	<div class="handler">
Elliott Hughes	33bf975	2021-08-10 17:33:34 -0700	[diff] [blame]	1339	<h4 id="XML_SetCharacterDataHandler">XML_SetCharacterDataHandler</h4>
				1340	<pre class="setter">
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	1341	void XMLCALL
				1342	XML_SetCharacterDataHandler(XML_Parser p,
				1343	XML_CharacterDataHandler charhndl)
				1344	</pre>
				1345	<pre class="signature">
				1346	typedef void
				1347	(XMLCALL XML_CharacterDataHandler)(void userData,
				1348	const XML_Char *s,
				1349	int len);
				1350	</pre>
				1351	<p>Set a text handler. The string your handler receives
Haibo Huang	d1a324a	2020-10-28 22:19:36 -0700	[diff] [blame]	1352	is <em>NOT null-terminated</em>. You have to use the length argument
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	1353	to deal with the end of the string. A single block of contiguous text
				1354	free of markup may still result in a sequence of calls to this handler.
				1355	In other words, if you're searching for a pattern in the text, it may
Elliott Hughes	d07d5a7	2009-09-25 16:04:37 -0700	[diff] [blame]	1356	be split across calls to this handler. Note: Setting this handler to NULL
				1357	may <em>NOT immediately</em> terminate call-backs if the parser is currently
				1358	processing such a single block of contiguous markup-free text, as the parser
				1359	will continue calling back until the end of the block is reached.</p>
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	1360	</div>
				1361
				1362	<div class="handler">
Elliott Hughes	33bf975	2021-08-10 17:33:34 -0700	[diff] [blame]	1363	<h4 id="XML_SetProcessingInstructionHandler">XML_SetProcessingInstructionHandler</h4>
				1364	<pre class="setter">
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	1365	void XMLCALL
				1366	XML_SetProcessingInstructionHandler(XML_Parser p,
				1367	XML_ProcessingInstructionHandler proc)
				1368	</pre>
				1369	<pre class="signature">
				1370	typedef void
				1371	(XMLCALL XML_ProcessingInstructionHandler)(void userData,
				1372	const XML_Char *target,
				1373	const XML_Char *data);
				1374
				1375	</pre>
				1376	<p>Set a handler for processing instructions. The target is the first word
				1377	in the processing instruction. The data is the rest of the characters in
				1378	it after skipping all whitespace after the initial word.</p>
				1379	</div>
				1380
				1381	<div class="handler">
Elliott Hughes	33bf975	2021-08-10 17:33:34 -0700	[diff] [blame]	1382	<h4 id="XML_SetCommentHandler">XML_SetCommentHandler</h4>
				1383	<pre class="setter">
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	1384	void XMLCALL
				1385	XML_SetCommentHandler(XML_Parser p,
				1386	XML_CommentHandler cmnt)
				1387	</pre>
				1388	<pre class="signature">
				1389	typedef void
				1390	(XMLCALL XML_CommentHandler)(void userData,
				1391	const XML_Char *data);
				1392	</pre>
				1393	<p>Set a handler for comments. The data is all text inside the comment
				1394	delimiters.</p>
				1395	</div>
				1396
				1397	<div class="handler">
Elliott Hughes	33bf975	2021-08-10 17:33:34 -0700	[diff] [blame]	1398	<h4 id="XML_SetStartCdataSectionHandler">XML_SetStartCdataSectionHandler</h4>
				1399	<pre class="setter">
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	1400	void XMLCALL
				1401	XML_SetStartCdataSectionHandler(XML_Parser p,
				1402	XML_StartCdataSectionHandler start);
				1403	</pre>
				1404	<pre class="signature">
				1405	typedef void
				1406	(XMLCALL XML_StartCdataSectionHandler)(void userData);
				1407	</pre>
				1408	<p>Set a handler that gets called at the beginning of a CDATA section.</p>
				1409	</div>
				1410
				1411	<div class="handler">
Elliott Hughes	33bf975	2021-08-10 17:33:34 -0700	[diff] [blame]	1412	<h4 id="XML_SetEndCdataSectionHandler">XML_SetEndCdataSectionHandler</h4>
				1413	<pre class="setter">
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	1414	void XMLCALL
				1415	XML_SetEndCdataSectionHandler(XML_Parser p,
				1416	XML_EndCdataSectionHandler end);
				1417	</pre>
				1418	<pre class="signature">
				1419	typedef void
				1420	(XMLCALL XML_EndCdataSectionHandler)(void userData);
				1421	</pre>
				1422	<p>Set a handler that gets called at the end of a CDATA section.</p>
				1423	</div>
				1424
				1425	<div class="handler">
Elliott Hughes	33bf975	2021-08-10 17:33:34 -0700	[diff] [blame]	1426	<h4 id="XML_SetCdataSectionHandler">XML_SetCdataSectionHandler</h4>
				1427	<pre class="setter">
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	1428	void XMLCALL
				1429	XML_SetCdataSectionHandler(XML_Parser p,
				1430	XML_StartCdataSectionHandler start,
				1431	XML_EndCdataSectionHandler end)
				1432	</pre>
				1433	<p>Sets both CDATA section handlers with one call.</p>
				1434	</div>
				1435
				1436	<div class="handler">
Elliott Hughes	33bf975	2021-08-10 17:33:34 -0700	[diff] [blame]	1437	<h4 id="XML_SetDefaultHandler">XML_SetDefaultHandler</h4>
				1438	<pre class="setter">
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	1439	void XMLCALL
				1440	XML_SetDefaultHandler(XML_Parser p,
				1441	XML_DefaultHandler hndl)
				1442	</pre>
				1443	<pre class="signature">
				1444	typedef void
				1445	(XMLCALL XML_DefaultHandler)(void userData,
				1446	const XML_Char *s,
				1447	int len);
				1448	</pre>
				1449
				1450	<p>Sets a handler for any characters in the document which wouldn't
				1451	otherwise be handled. This includes both data for which no handlers
				1452	can be set (like some kinds of DTD declarations) and data which could
				1453	be reported but which currently has no handler set. The characters
				1454	are passed exactly as they were present in the XML document except
				1455	that they will be encoded in UTF-8 or UTF-16. Line boundaries are not
				1456	normalized. Note that a byte order mark character is not passed to the
				1457	default handler. There are no guarantees about how characters are
				1458	divided between calls to the default handler: for example, a comment
				1459	might be split between multiple calls. Setting the handler with
				1460	this call has the side effect of turning off expansion of references
				1461	to internally defined general entities. Instead these references are
				1462	passed to the default handler.</p>
				1463
				1464	<p>See also <code><a
				1465	href="#XML_DefaultCurrent">XML_DefaultCurrent</a></code>.</p>
				1466	</div>
				1467
				1468	<div class="handler">
Elliott Hughes	33bf975	2021-08-10 17:33:34 -0700	[diff] [blame]	1469	<h4 id="XML_SetDefaultHandlerExpand">XML_SetDefaultHandlerExpand</h4>
				1470	<pre class="setter">
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	1471	void XMLCALL
				1472	XML_SetDefaultHandlerExpand(XML_Parser p,
				1473	XML_DefaultHandler hndl)
				1474	</pre>
				1475	<pre class="signature">
				1476	typedef void
				1477	(XMLCALL XML_DefaultHandler)(void userData,
				1478	const XML_Char *s,
				1479	int len);
				1480	</pre>
				1481	<p>This sets a default handler, but doesn't inhibit the expansion of
				1482	internal entity references. The entity reference will not be passed
				1483	to the default handler.</p>
				1484
				1485	<p>See also <code><a
				1486	href="#XML_DefaultCurrent">XML_DefaultCurrent</a></code>.</p>
				1487	</div>
				1488
				1489	<div class="handler">
Elliott Hughes	33bf975	2021-08-10 17:33:34 -0700	[diff] [blame]	1490	<h4 id="XML_SetExternalEntityRefHandler">XML_SetExternalEntityRefHandler</h4>
				1491	<pre class="setter">
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	1492	void XMLCALL
				1493	XML_SetExternalEntityRefHandler(XML_Parser p,
				1494	XML_ExternalEntityRefHandler hndl)
				1495	</pre>
				1496	<pre class="signature">
				1497	typedef int
				1498	(XMLCALL *XML_ExternalEntityRefHandler)(XML_Parser p,
				1499	const XML_Char *context,
				1500	const XML_Char *base,
				1501	const XML_Char *systemId,
				1502	const XML_Char *publicId);
				1503	</pre>
				1504	<p>Set an external entity reference handler. This handler is also
				1505	called for processing an external DTD subset if parameter entity parsing
				1506	is in effect. (See <a href="#XML_SetParamEntityParsing">
				1507	<code>XML_SetParamEntityParsing</code></a>.)</p>
				1508
				1509	<p>The <code>context</code> parameter specifies the parsing context in
				1510	the format expected by the <code>context</code> argument to <code><a
				1511	href="#XML_ExternalEntityParserCreate"
				1512	>XML_ExternalEntityParserCreate</a></code>. <code>code</code> is
				1513	valid only until the handler returns, so if the referenced entity is
				1514	to be parsed later, it must be copied. <code>context</code> is NULL
				1515	only when the entity is a parameter entity, which is how one can
				1516	differentiate between general and parameter entities.</p>
				1517
				1518	<p>The <code>base</code> parameter is the base to use for relative
				1519	system identifiers. It is set by <code><a
				1520	href="#XML_SetBase">XML_SetBase</a></code> and may be NULL. The
				1521	<code>publicId</code> parameter is the public id given in the entity
				1522	declaration and may be NULL. <code>systemId</code> is the system
				1523	identifier specified in the entity declaration and is never NULL.</p>
				1524
				1525	<p>There are a couple of ways in which this handler differs from
				1526	others. First, this handler returns a status indicator (an
				1527	integer). <code>XML_STATUS_OK</code> should be returned for successful
				1528	handling of the external entity reference. Returning
				1529	<code>XML_STATUS_ERROR</code> indicates failure, and causes the
				1530	calling parser to return an
				1531	<code>XML_ERROR_EXTERNAL_ENTITY_HANDLING</code> error.</p>
				1532
				1533	<p>Second, instead of having the user data as its first argument, it
				1534	receives the parser that encountered the entity reference. This, along
				1535	with the context parameter, may be used as arguments to a call to
				1536	<code><a href= "#XML_ExternalEntityParserCreate"
				1537	>XML_ExternalEntityParserCreate</a></code>. Using the returned
				1538	parser, the body of the external entity can be recursively parsed.</p>
				1539
				1540	<p>Since this handler may be called recursively, it should not be saving
				1541	information into global or static variables.</p>
				1542	</div>
				1543
Elliott Hughes	33bf975	2021-08-10 17:33:34 -0700	[diff] [blame]	1544	<h4 id="XML_SetExternalEntityRefHandlerArg">XML_SetExternalEntityRefHandlerArg</h4>
				1545	<pre class="fcndec">
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	1546	void XMLCALL
				1547	XML_SetExternalEntityRefHandlerArg(XML_Parser p,
				1548	void *arg)
				1549	</pre>
				1550	<div class="fcndef">
				1551	<p>Set the argument passed to the ExternalEntityRefHandler. If
				1552	<code>arg</code> is not NULL, it is the new value passed to the
				1553	handler set using <code><a href="#XML_SetExternalEntityRefHandler"
				1554	>XML_SetExternalEntityRefHandler</a></code>; if <code>arg</code> is
				1555	NULL, the argument passed to the handler function will be the parser
				1556	object itself.</p>
				1557
				1558	<p><strong>Note:</strong>
				1559	The type of <code>arg</code> and the type of the first argument to the
				1560	ExternalEntityRefHandler do not match. This function takes a
				1561	<code>void *</code> to be passed to the handler, while the handler
				1562	accepts an <code>XML_Parser</code>. This is a historical accident,
				1563	but will not be corrected before Expat 2.0 (at the earliest) to avoid
				1564	causing compiler warnings for code that's known to work with this
				1565	API. It is the responsibility of the application code to know the
				1566	actual type of the argument passed to the handler and to manage it
				1567	properly.</p>
				1568	</div>
				1569
				1570	<div class="handler">
Elliott Hughes	33bf975	2021-08-10 17:33:34 -0700	[diff] [blame]	1571	<h4 id="XML_SetSkippedEntityHandler">XML_SetSkippedEntityHandler</h4>
				1572	<pre class="setter">
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	1573	void XMLCALL
				1574	XML_SetSkippedEntityHandler(XML_Parser p,
				1575	XML_SkippedEntityHandler handler)
				1576	</pre>
				1577	<pre class="signature">
				1578	typedef void
				1579	(XMLCALL XML_SkippedEntityHandler)(void userData,
				1580	const XML_Char *entityName,
				1581	int is_parameter_entity);
				1582	</pre>
				1583	<p>Set a skipped entity handler. This is called in two situations:</p>
				1584	<ol>
				1585	<li>An entity reference is encountered for which no declaration
				1586	has been read <em>and</em> this is not an error.</li>
				1587	<li>An internal entity reference is read, but not expanded, because
				1588	<a href="#XML_SetDefaultHandler"><code>XML_SetDefaultHandler</code></a>
				1589	has been called.</li>
				1590	</ol>
				1591	<p>The <code>is_parameter_entity</code> argument will be non-zero for
Elliott Hughes	33bf975	2021-08-10 17:33:34 -0700	[diff] [blame]	1592	a parameter entity and zero for a general entity.</p> <p>Note: Skipped
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	1593	parameter entities in declarations and skipped general entities in
				1594	attribute values cannot be reported, because the event would be out of
				1595	sync with the reporting of the declarations or attribute values</p>
				1596	</div>
				1597
				1598	<div class="handler">
Elliott Hughes	33bf975	2021-08-10 17:33:34 -0700	[diff] [blame]	1599	<h4 id="XML_SetUnknownEncodingHandler">XML_SetUnknownEncodingHandler</h4>
				1600	<pre class="setter">
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	1601	void XMLCALL
				1602	XML_SetUnknownEncodingHandler(XML_Parser p,
				1603	XML_UnknownEncodingHandler enchandler,
				1604	void *encodingHandlerData)
				1605	</pre>
				1606	<pre class="signature">
				1607	typedef int
				1608	(XMLCALL XML_UnknownEncodingHandler)(void encodingHandlerData,
				1609	const XML_Char *name,
				1610	XML_Encoding *info);
				1611
				1612	typedef struct {
				1613	int map[256];
				1614	void *data;
				1615	int (XMLCALL convert)(void data, const char *s);
				1616	void (XMLCALL release)(void data);
				1617	} XML_Encoding;
				1618	</pre>
				1619	<p>Set a handler to deal with encodings other than the <a
				1620	href="#builtin_encodings">built in set</a>. This should be done before
				1621	<code><a href= "#XML_Parse" >XML_Parse</a></code> or <code><a href=
				1622	"#XML_ParseBuffer" >XML_ParseBuffer</a></code> have been called on the
				1623	given parser.</p> <p>If the handler knows how to deal with an encoding
				1624	with the given name, it should fill in the <code>info</code> data
				1625	structure and return <code>XML_STATUS_OK</code>. Otherwise it
				1626	should return <code>XML_STATUS_ERROR</code>. The handler will be called
				1627	at most once per parsed (external) entity. The optional application
				1628	data pointer <code>encodingHandlerData</code> will be passed back to
				1629	the handler.</p>
				1630
Elliott Hughes	7247294	2018-01-10 08:36:10 -0800	[diff] [blame]	1631	<p>The map array contains information for every possible leading
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	1632	byte in a byte sequence. If the corresponding value is >= 0, then it's
				1633	a single byte sequence and the byte encodes that Unicode value. If the
				1634	value is -1, then that byte is invalid as the initial byte in a sequence.
				1635	If the value is -n, where n is an integer > 1, then n is the number of
				1636	bytes in the sequence and the actual conversion is accomplished by a
				1637	call to the function pointed at by convert. This function may return -1
				1638	if the sequence itself is invalid. The convert pointer may be null if
				1639	there are only single byte codes. The data parameter passed to the convert
				1640	function is the data pointer from <code>XML_Encoding</code>. The
Haibo Huang	d1a324a	2020-10-28 22:19:36 -0700	[diff] [blame]	1641	string s is <em>NOT</em> null-terminated and points at the sequence of
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	1642	bytes to be converted.</p>
				1643
				1644	<p>The function pointed at by <code>release</code> is called by the
				1645	parser when it is finished with the encoding. It may be NULL.</p>
				1646	</div>
				1647
				1648	<div class="handler">
Elliott Hughes	33bf975	2021-08-10 17:33:34 -0700	[diff] [blame]	1649	<h4 id="XML_SetStartNamespaceDeclHandler">XML_SetStartNamespaceDeclHandler</h4>
				1650	<pre class="setter">
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	1651	void XMLCALL
				1652	XML_SetStartNamespaceDeclHandler(XML_Parser p,
				1653	XML_StartNamespaceDeclHandler start);
				1654	</pre>
				1655	<pre class="signature">
				1656	typedef void
				1657	(XMLCALL XML_StartNamespaceDeclHandler)(void userData,
				1658	const XML_Char *prefix,
				1659	const XML_Char *uri);
				1660	</pre>
				1661	<p>Set a handler to be called when a namespace is declared. Namespace
				1662	declarations occur inside start tags. But the namespace declaration start
				1663	handler is called before the start tag handler for each namespace declared
				1664	in that start tag.</p>
				1665	</div>
				1666
				1667	<div class="handler">
Elliott Hughes	33bf975	2021-08-10 17:33:34 -0700	[diff] [blame]	1668	<h4 id="XML_SetEndNamespaceDeclHandler">XML_SetEndNamespaceDeclHandler</h4>
				1669	<pre class="setter">
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	1670	void XMLCALL
				1671	XML_SetEndNamespaceDeclHandler(XML_Parser p,
				1672	XML_EndNamespaceDeclHandler end);
				1673	</pre>
				1674	<pre class="signature">
				1675	typedef void
				1676	(XMLCALL XML_EndNamespaceDeclHandler)(void userData,
				1677	const XML_Char *prefix);
				1678	</pre>
				1679	<p>Set a handler to be called when leaving the scope of a namespace
				1680	declaration. This will be called, for each namespace declaration,
				1681	after the handler for the end tag of the element in which the
				1682	namespace was declared.</p>
				1683	</div>
				1684
				1685	<div class="handler">
Elliott Hughes	33bf975	2021-08-10 17:33:34 -0700	[diff] [blame]	1686	<h4 id="XML_SetNamespaceDeclHandler">XML_SetNamespaceDeclHandler</h4>
				1687	<pre class="setter">
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	1688	void XMLCALL
				1689	XML_SetNamespaceDeclHandler(XML_Parser p,
				1690	XML_StartNamespaceDeclHandler start,
				1691	XML_EndNamespaceDeclHandler end)
				1692	</pre>
				1693	<p>Sets both namespace declaration handlers with a single call.</p>
				1694	</div>
				1695
				1696	<div class="handler">
Elliott Hughes	33bf975	2021-08-10 17:33:34 -0700	[diff] [blame]	1697	<h4 id="XML_SetXmlDeclHandler">XML_SetXmlDeclHandler</h4>
				1698	<pre class="setter">
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	1699	void XMLCALL
				1700	XML_SetXmlDeclHandler(XML_Parser p,
				1701	XML_XmlDeclHandler xmldecl);
				1702	</pre>
				1703	<pre class="signature">
				1704	typedef void
				1705	(XMLCALL XML_XmlDeclHandler)(void userData,
				1706	const XML_Char *version,
				1707	const XML_Char *encoding,
				1708	int standalone);
				1709	</pre>
				1710	<p>Sets a handler that is called for XML declarations and also for
				1711	text declarations discovered in external entities. The way to
				1712	distinguish is that the <code>version</code> parameter will be NULL
				1713	for text declarations. The <code>encoding</code> parameter may be NULL
				1714	for an XML declaration. The <code>standalone</code> argument will
				1715	contain -1, 0, or 1 indicating respectively that there was no
				1716	standalone parameter in the declaration, that it was given as no, or
				1717	that it was given as yes.</p>
				1718	</div>
				1719
				1720	<div class="handler">
Elliott Hughes	33bf975	2021-08-10 17:33:34 -0700	[diff] [blame]	1721	<h4 id="XML_SetStartDoctypeDeclHandler">XML_SetStartDoctypeDeclHandler</h4>
				1722	<pre class="setter">
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	1723	void XMLCALL
				1724	XML_SetStartDoctypeDeclHandler(XML_Parser p,
				1725	XML_StartDoctypeDeclHandler start);
				1726	</pre>
				1727	<pre class="signature">
				1728	typedef void
				1729	(XMLCALL XML_StartDoctypeDeclHandler)(void userData,
				1730	const XML_Char *doctypeName,
				1731	const XML_Char *sysid,
				1732	const XML_Char *pubid,
				1733	int has_internal_subset);
				1734	</pre>
				1735	<p>Set a handler that is called at the start of a DOCTYPE declaration,
				1736	before any external or internal subset is parsed. Both <code>sysid</code>
				1737	and <code>pubid</code> may be NULL. The <code>has_internal_subset</code>
				1738	will be non-zero if the DOCTYPE declaration has an internal subset.</p>
				1739	</div>
				1740
				1741	<div class="handler">
Elliott Hughes	33bf975	2021-08-10 17:33:34 -0700	[diff] [blame]	1742	<h4 id="XML_SetEndDoctypeDeclHandler">XML_SetEndDoctypeDeclHandler</h4>
				1743	<pre class="setter">
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	1744	void XMLCALL
				1745	XML_SetEndDoctypeDeclHandler(XML_Parser p,
				1746	XML_EndDoctypeDeclHandler end);
				1747	</pre>
				1748	<pre class="signature">
				1749	typedef void
				1750	(XMLCALL XML_EndDoctypeDeclHandler)(void userData);
				1751	</pre>
				1752	<p>Set a handler that is called at the end of a DOCTYPE declaration,
				1753	after parsing any external subset.</p>
				1754	</div>
				1755
				1756	<div class="handler">
Elliott Hughes	33bf975	2021-08-10 17:33:34 -0700	[diff] [blame]	1757	<h4 id="XML_SetDoctypeDeclHandler">XML_SetDoctypeDeclHandler</h4>
				1758	<pre class="setter">
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	1759	void XMLCALL
				1760	XML_SetDoctypeDeclHandler(XML_Parser p,
				1761	XML_StartDoctypeDeclHandler start,
				1762	XML_EndDoctypeDeclHandler end);
				1763	</pre>
				1764	<p>Set both doctype handlers with one call.</p>
				1765	</div>
				1766
				1767	<div class="handler">
Elliott Hughes	33bf975	2021-08-10 17:33:34 -0700	[diff] [blame]	1768	<h4 id="XML_SetElementDeclHandler">XML_SetElementDeclHandler</h4>
				1769	<pre class="setter">
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	1770	void XMLCALL
				1771	XML_SetElementDeclHandler(XML_Parser p,
				1772	XML_ElementDeclHandler eldecl);
				1773	</pre>
				1774	<pre class="signature">
				1775	typedef void
				1776	(XMLCALL XML_ElementDeclHandler)(void userData,
				1777	const XML_Char *name,
				1778	XML_Content *model);
				1779	</pre>
				1780	<pre class="signature">
				1781	enum XML_Content_Type {
				1782	XML_CTYPE_EMPTY = 1,
				1783	XML_CTYPE_ANY,
				1784	XML_CTYPE_MIXED,
				1785	XML_CTYPE_NAME,
				1786	XML_CTYPE_CHOICE,
				1787	XML_CTYPE_SEQ
				1788	};
				1789
				1790	enum XML_Content_Quant {
				1791	XML_CQUANT_NONE,
				1792	XML_CQUANT_OPT,
				1793	XML_CQUANT_REP,
				1794	XML_CQUANT_PLUS
				1795	};
				1796
				1797	typedef struct XML_cp XML_Content;
				1798
				1799	struct XML_cp {
				1800	enum XML_Content_Type type;
				1801	enum XML_Content_Quant quant;
				1802	const XML_Char * name;
				1803	unsigned int numchildren;
				1804	XML_Content * children;
				1805	};
				1806	</pre>
				1807	<p>Sets a handler for element declarations in a DTD. The handler gets
				1808	called with the name of the element in the declaration and a pointer
				1809	to a structure that contains the element model. It is the
				1810	application's responsibility to free this data structure using
				1811	<code><a href="#XML_FreeContentModel"
				1812	>XML_FreeContentModel</a></code>.</p>
				1813
				1814	<p>The <code>model</code> argument is the root of a tree of
				1815	<code>XML_Content</code> nodes. If <code>type</code> equals
				1816	<code>XML_CTYPE_EMPTY</code> or <code>XML_CTYPE_ANY</code>, then
				1817	<code>quant</code> will be <code>XML_CQUANT_NONE</code>, and the other
				1818	fields will be zero or NULL. If <code>type</code> is
				1819	<code>XML_CTYPE_MIXED</code>, then <code>quant</code> will be
				1820	<code>XML_CQUANT_NONE</code> or <code>XML_CQUANT_REP</code> and
				1821	<code>numchildren</code> will contain the number of elements that are
				1822	allowed to be mixed in and <code>children</code> points to an array of
				1823	<code>XML_Content</code> structures that will all have type
				1824	XML_CTYPE_NAME with no quantification. Only the root node can be type
				1825	<code>XML_CTYPE_EMPTY</code>, <code>XML_CTYPE_ANY</code>, or
				1826	<code>XML_CTYPE_MIXED</code>.</p>
				1827
				1828	<p>For type <code>XML_CTYPE_NAME</code>, the <code>name</code> field
				1829	points to the name and the <code>numchildren</code> and
				1830	<code>children</code> fields will be zero and NULL. The
				1831	<code>quant</code> field will indicate any quantifiers placed on the
				1832	name.</p>
				1833
				1834	<p>Types <code>XML_CTYPE_CHOICE</code> and <code>XML_CTYPE_SEQ</code>
				1835	indicate a choice or sequence respectively. The
				1836	<code>numchildren</code> field indicates how many nodes in the choice
				1837	or sequence and <code>children</code> points to the nodes.</p>
				1838	</div>
				1839
				1840	<div class="handler">
Elliott Hughes	33bf975	2021-08-10 17:33:34 -0700	[diff] [blame]	1841	<h4 id="XML_SetAttlistDeclHandler">XML_SetAttlistDeclHandler</h4>
				1842	<pre class="setter">
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	1843	void XMLCALL
				1844	XML_SetAttlistDeclHandler(XML_Parser p,
				1845	XML_AttlistDeclHandler attdecl);
				1846	</pre>
				1847	<pre class="signature">
				1848	typedef void
				1849	(XMLCALL XML_AttlistDeclHandler)(void userData,
				1850	const XML_Char *elname,
				1851	const XML_Char *attname,
				1852	const XML_Char *att_type,
				1853	const XML_Char *dflt,
				1854	int isrequired);
				1855	</pre>
				1856	<p>Set a handler for attlist declarations in the DTD. This handler is
				1857	called for <em>each</em> attribute. So a single attlist declaration
				1858	with multiple attributes declared will generate multiple calls to this
				1859	handler. The <code>elname</code> parameter returns the name of the
				1860	element for which the attribute is being declared. The attribute name
				1861	is in the <code>attname</code> parameter. The attribute type is in the
				1862	<code>att_type</code> parameter. It is the string representing the
				1863	type in the declaration with whitespace removed.</p>
				1864
				1865	<p>The <code>dflt</code> parameter holds the default value. It will be
				1866	NULL in the case of "#IMPLIED" or "#REQUIRED" attributes. You can
				1867	distinguish these two cases by checking the <code>isrequired</code>
				1868	parameter, which will be true in the case of "#REQUIRED" attributes.
				1869	Attributes which are "#FIXED" will have also have a true
				1870	<code>isrequired</code>, but they will have the non-NULL fixed value
				1871	in the <code>dflt</code> parameter.</p>
				1872	</div>
				1873
				1874	<div class="handler">
Elliott Hughes	33bf975	2021-08-10 17:33:34 -0700	[diff] [blame]	1875	<h4 id="XML_SetEntityDeclHandler">XML_SetEntityDeclHandler</h4>
				1876	<pre class="setter">
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	1877	void XMLCALL
				1878	XML_SetEntityDeclHandler(XML_Parser p,
				1879	XML_EntityDeclHandler handler);
				1880	</pre>
				1881	<pre class="signature">
				1882	typedef void
				1883	(XMLCALL XML_EntityDeclHandler)(void userData,
				1884	const XML_Char *entityName,
				1885	int is_parameter_entity,
				1886	const XML_Char *value,
				1887	int value_length,
				1888	const XML_Char *base,
				1889	const XML_Char *systemId,
				1890	const XML_Char *publicId,
				1891	const XML_Char *notationName);
				1892	</pre>
				1893	<p>Sets a handler that will be called for all entity declarations.
				1894	The <code>is_parameter_entity</code> argument will be non-zero in the
				1895	case of parameter entities and zero otherwise.</p>
				1896
				1897	<p>For internal entities (<code><!ENTITY foo "bar"></code>),
				1898	<code>value</code> will be non-NULL and <code>systemId</code>,
				1899	<code>publicId</code>, and <code>notationName</code> will all be NULL.
				1900	The value string is <em>not</em> NULL terminated; the length is
				1901	provided in the <code>value_length</code> parameter. Do not use
				1902	<code>value_length</code> to test for internal entities, since it is
				1903	legal to have zero-length values. Instead check for whether or not
				1904	<code>value</code> is NULL.</p> <p>The <code>notationName</code>
				1905	argument will have a non-NULL value only for unparsed entity
				1906	declarations.</p>
				1907	</div>
				1908
				1909	<div class="handler">
Elliott Hughes	33bf975	2021-08-10 17:33:34 -0700	[diff] [blame]	1910	<h4 id="XML_SetUnparsedEntityDeclHandler">XML_SetUnparsedEntityDeclHandler</h4>
				1911	<pre class="setter">
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	1912	void XMLCALL
				1913	XML_SetUnparsedEntityDeclHandler(XML_Parser p,
				1914	XML_UnparsedEntityDeclHandler h)
				1915	</pre>
				1916	<pre class="signature">
				1917	typedef void
				1918	(XMLCALL XML_UnparsedEntityDeclHandler)(void userData,
				1919	const XML_Char *entityName,
				1920	const XML_Char *base,
				1921	const XML_Char *systemId,
				1922	const XML_Char *publicId,
				1923	const XML_Char *notationName);
				1924	</pre>
				1925	<p>Set a handler that receives declarations of unparsed entities. These
				1926	are entity declarations that have a notation (NDATA) field:</p>
				1927
				1928	<div id="eg"><pre>
				1929	<!ENTITY logo SYSTEM "images/logo.gif" NDATA gif>
				1930	</pre></div>
				1931	<p>This handler is obsolete and is provided for backwards
				1932	compatibility. Use instead <a href= "#XML_SetEntityDeclHandler"
				1933	>XML_SetEntityDeclHandler</a>.</p>
				1934	</div>
				1935
				1936	<div class="handler">
Elliott Hughes	33bf975	2021-08-10 17:33:34 -0700	[diff] [blame]	1937	<h4 id="XML_SetNotationDeclHandler">XML_SetNotationDeclHandler</h4>
				1938	<pre class="setter">
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	1939	void XMLCALL
				1940	XML_SetNotationDeclHandler(XML_Parser p,
				1941	XML_NotationDeclHandler h)
				1942	</pre>
				1943	<pre class="signature">
				1944	typedef void
				1945	(XMLCALL XML_NotationDeclHandler)(void userData,
				1946	const XML_Char *notationName,
				1947	const XML_Char *base,
				1948	const XML_Char *systemId,
				1949	const XML_Char *publicId);
				1950	</pre>
				1951	<p>Set a handler that receives notation declarations.</p>
				1952	</div>
				1953
				1954	<div class="handler">
Elliott Hughes	33bf975	2021-08-10 17:33:34 -0700	[diff] [blame]	1955	<h4 id="XML_SetNotStandaloneHandler">XML_SetNotStandaloneHandler</h4>
				1956	<pre class="setter">
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	1957	void XMLCALL
				1958	XML_SetNotStandaloneHandler(XML_Parser p,
				1959	XML_NotStandaloneHandler h)
				1960	</pre>
				1961	<pre class="signature">
				1962	typedef int
				1963	(XMLCALL XML_NotStandaloneHandler)(void userData);
				1964	</pre>
				1965	<p>Set a handler that is called if the document is not "standalone".
				1966	This happens when there is an external subset or a reference to a
				1967	parameter entity, but does not have standalone set to "yes" in an XML
				1968	declaration. If this handler returns <code>XML_STATUS_ERROR</code>,
				1969	then the parser will throw an <code>XML_ERROR_NOT_STANDALONE</code>
				1970	error.</p>
				1971	</div>
				1972
				1973	<h3><a name="position">Parse position and error reporting functions</a></h3>
				1974
				1975	<p>These are the functions you'll want to call when the parse
				1976	functions return <code>XML_STATUS_ERROR</code> (a parse error has
				1977	occurred), although the position reporting functions are useful outside
				1978	of errors. The position reported is the byte position (in the original
				1979	document or entity encoding) of the first of the sequence of
				1980	characters that generated the current event (or the error that caused
				1981	the parse functions to return <code>XML_STATUS_ERROR</code>.) The
Haibo Huang	d1a324a	2020-10-28 22:19:36 -0700	[diff] [blame]	1982	exceptions are callbacks triggered by declarations in the document
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	1983	prologue, in which case they exact position reported is somewhere in the
				1984	relevant markup, but not necessarily as meaningful as for other
				1985	events.</p>
				1986
				1987	<p>The position reporting functions are accurate only outside of the
				1988	DTD. In other words, they usually return bogus information when
				1989	called from within a DTD declaration handler.</p>
				1990
Elliott Hughes	33bf975	2021-08-10 17:33:34 -0700	[diff] [blame]	1991	<h4 id="XML_GetErrorCode">XML_GetErrorCode</h4>
				1992	<pre class="fcndec">
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	1993	enum XML_Error XMLCALL
				1994	XML_GetErrorCode(XML_Parser p);
				1995	</pre>
				1996	<div class="fcndef">
				1997	Return what type of error has occurred.
				1998	</div>
				1999
Elliott Hughes	33bf975	2021-08-10 17:33:34 -0700	[diff] [blame]	2000	<h4 id="XML_ErrorString">XML_ErrorString</h4>
				2001	<pre class="fcndec">
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	2002	const XML_LChar * XMLCALL
				2003	XML_ErrorString(enum XML_Error code);
				2004	</pre>
				2005	<div class="fcndef">
				2006	Return a string describing the error corresponding to code.
				2007	The code should be one of the enums that can be returned from
				2008	<code><a href= "#XML_GetErrorCode" >XML_GetErrorCode</a></code>.
				2009	</div>
				2010
Elliott Hughes	33bf975	2021-08-10 17:33:34 -0700	[diff] [blame]	2011	<h4 id="XML_GetCurrentByteIndex">XML_GetCurrentByteIndex</h4>
				2012	<pre class="fcndec">
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	2013	XML_Index XMLCALL
				2014	XML_GetCurrentByteIndex(XML_Parser p);
				2015	</pre>
				2016	<div class="fcndef">
				2017	Return the byte offset of the position. This always corresponds to
				2018	the values returned by <code><a href= "#XML_GetCurrentLineNumber"
				2019	>XML_GetCurrentLineNumber</a></code> and <code><a href=
				2020	"#XML_GetCurrentColumnNumber" >XML_GetCurrentColumnNumber</a></code>.
				2021	</div>
				2022
Elliott Hughes	33bf975	2021-08-10 17:33:34 -0700	[diff] [blame]	2023	<h4 id="XML_GetCurrentLineNumber">XML_GetCurrentLineNumber</h4>
				2024	<pre class="fcndec">
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	2025	XML_Size XMLCALL
				2026	XML_GetCurrentLineNumber(XML_Parser p);
				2027	</pre>
				2028	<div class="fcndef">
				2029	Return the line number of the position. The first line is reported as
				2030	<code>1</code>.
				2031	</div>
				2032
Elliott Hughes	33bf975	2021-08-10 17:33:34 -0700	[diff] [blame]	2033	<h4 id="XML_GetCurrentColumnNumber">XML_GetCurrentColumnNumber</h4>
				2034	<pre class="fcndec">
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	2035	XML_Size XMLCALL
				2036	XML_GetCurrentColumnNumber(XML_Parser p);
				2037	</pre>
				2038	<div class="fcndef">
				2039	Return the offset, from the beginning of the current line, of
				2040	the position.
				2041	</div>
				2042
Elliott Hughes	33bf975	2021-08-10 17:33:34 -0700	[diff] [blame]	2043	<h4 id="XML_GetCurrentByteCount">XML_GetCurrentByteCount</h4>
				2044	<pre class="fcndec">
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	2045	int XMLCALL
				2046	XML_GetCurrentByteCount(XML_Parser p);
				2047	</pre>
				2048	<div class="fcndef">
				2049	Return the number of bytes in the current event. Returns
				2050	<code>0</code> if the event is inside a reference to an internal
				2051	entity and for the end-tag event for empty element tags (the later can
				2052	be used to distinguish empty-element tags from empty elements using
				2053	separate start and end tags).
				2054	</div>
				2055
Elliott Hughes	33bf975	2021-08-10 17:33:34 -0700	[diff] [blame]	2056	<h4 id="XML_GetInputContext">XML_GetInputContext</h4>
				2057	<pre class="fcndec">
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	2058	const char * XMLCALL
				2059	XML_GetInputContext(XML_Parser p,
				2060	int *offset,
				2061	int *size);
				2062	</pre>
				2063	<div class="fcndef">
				2064
				2065	<p>Returns the parser's input buffer, sets the integer pointed at by
				2066	<code>offset</code> to the offset within this buffer of the current
				2067	parse position, and set the integer pointed at by <code>size</code> to
				2068	the size of the returned buffer.</p>
				2069
				2070	<p>This should only be called from within a handler during an active
				2071	parse and the returned buffer should only be referred to from within
				2072	the handler that made the call. This input buffer contains the
				2073	untranslated bytes of the input.</p>
				2074
				2075	<p>Only a limited amount of context is kept, so if the event
				2076	triggering a call spans over a very large amount of input, the actual
				2077	parse position may be before the beginning of the buffer.</p>
				2078
				2079	<p>If <code>XML_CONTEXT_BYTES</code> is not defined, this will always
				2080	return NULL.</p>
				2081	</div>
				2082
Elliott Hughes	33bf975	2021-08-10 17:33:34 -0700	[diff] [blame]	2083	<h3><a name="billion-laughs">Billion Laughs Attack Protection</a></h3>
				2084
				2085	<p>The functions in this section configure the built-in
				2086	protection against various forms of
				2087	<a href="https://en.wikipedia.org/wiki/Billion_laughs_attack">billion laughs attacks</a>.</p>
				2088
				2089	<h4 id="XML_SetBillionLaughsAttackProtectionMaximumAmplification">XML_SetBillionLaughsAttackProtectionMaximumAmplification</h4>
				2090	<pre class="fcndec">
				2091	/* Added in Expat 2.4.0. */
				2092	XML_Bool XMLCALL
				2093	XML_SetBillionLaughsAttackProtectionMaximumAmplification(XML_Parser p,
				2094	float maximumAmplificationFactor);
				2095	</pre>
				2096	<div class="fcndef">
				2097	<p>
				2098	Sets the maximum tolerated amplification factor
				2099	for protection against
				2100	<a href="https://en.wikipedia.org/wiki/Billion_laughs_attack">billion laughs attacks</a>
				2101	(default: <code>100.0</code>)
				2102	of parser <code>p</code> to <code>maximumAmplificationFactor</code>, and
				2103	returns <code>XML_TRUE</code> upon success and <code>XML_TRUE</code> upon error.
				2104	</p>
				2105
				2106	The amplification factor is calculated as ..
				2107	<pre>
				2108	amplification := (direct + indirect) / direct
				2109	</pre>
				2110	.. while parsing, whereas
				2111	<code>direct</code> is the number of bytes read from the primary document in parsing and
				2112	<code>indirect</code> is the number of bytes added by expanding entities and reading of external DTD files, combined.
				2113
				2114	<p>For a call to <code>XML_SetBillionLaughsAttackProtectionMaximumAmplification</code> to succeed:</p>
				2115	<ul>
				2116	<li>parser <code>p</code> must be a non-<code>NULL</code> root parser (without any parent parsers) and</li>
				2117	<li><code>maximumAmplificationFactor</code> must be non-<code>NaN</code> and greater than or equal to <code>1.0</code>.</li>
				2118	</ul>
				2119
				2120	<p>
				2121	<strong>Note:</strong>
				2122	If you ever need to increase this value for non-attack payload,
				2123	please <a href="https://github.com/libexpat/libexpat/issues">file a bug report</a>.
				2124	</p>
				2125
				2126	<p>
				2127	<strong>Note:</strong>
				2128	Peak amplifications
				2129	of factor 15,000 for the entire payload and
				2130	of factor 30,000 in the middle of parsing
				2131	have been observed with small benign files in practice.
				2132
				2133	So if you do reduce the maximum allowed amplification,
				2134	please make sure that the activation threshold is still big enough
				2135	to not end up with undesired false positives (i.e. benign files being rejected).
				2136	</p>
				2137	</div>
				2138
				2139	<h4 id="XML_SetBillionLaughsAttackProtectionActivationThreshold">XML_SetBillionLaughsAttackProtectionActivationThreshold</h4>
				2140	<pre class="fcndec">
				2141	/* Added in Expat 2.4.0. */
				2142	XML_Bool XMLCALL
				2143	XML_SetBillionLaughsAttackProtectionActivationThreshold(XML_Parser p,
				2144	unsigned long long activationThresholdBytes);
				2145	</pre>
				2146	<div class="fcndef">
				2147	<p>
				2148	Sets number of output bytes (including amplification from entity expansion and reading DTD files)
				2149	needed to activate protection against
				2150	<a href="https://en.wikipedia.org/wiki/Billion_laughs_attack">billion laughs attacks</a>
				2151	(default: <code>8 MiB</code>)
				2152	of parser <code>p</code> to <code>activationThresholdBytes</code>, and
				2153	returns <code>XML_TRUE</code> upon success and <code>XML_TRUE</code> upon error.
				2154	</p>
				2155
				2156	<p>For a call to <code>XML_SetBillionLaughsAttackProtectionActivationThreshold</code> to succeed:</p>
				2157	<ul>
				2158	<li>parser <code>p</code> must be a non-<code>NULL</code> root parser (without any parent parsers).</li>
				2159	</ul>
				2160
				2161	<p>
				2162	<strong>Note:</strong>
				2163	If you ever need to increase this value for non-attack payload,
				2164	please <a href="https://github.com/libexpat/libexpat/issues">file a bug report</a>.
				2165	</p>
				2166
				2167	<p>
				2168	<strong>Note:</strong>
				2169	Activation thresholds below 4 MiB are known to break support for
				2170	<a href="https://en.wikipedia.org/wiki/Darwin_Information_Typing_Architecture">DITA</a> 1.3 payload
				2171	and are hence not recommended.
				2172	</p>
				2173	</div>
				2174
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	2175	<h3><a name="miscellaneous">Miscellaneous functions</a></h3>
				2176
				2177	<p>The functions in this section either obtain state information from
Elliott Hughes	7247294	2018-01-10 08:36:10 -0800	[diff] [blame]	2178	the parser or can be used to dynamically set parser options.</p>
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	2179
Elliott Hughes	33bf975	2021-08-10 17:33:34 -0700	[diff] [blame]	2180	<h4 id="XML_SetUserData">XML_SetUserData</h4>
				2181	<pre class="fcndec">
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	2182	void XMLCALL
				2183	XML_SetUserData(XML_Parser p,
				2184	void *userData);
				2185	</pre>
				2186	<div class="fcndef">
				2187	This sets the user data pointer that gets passed to handlers. It
				2188	overwrites any previous value for this pointer. Note that the
				2189	application is responsible for freeing the memory associated with
				2190	<code>userData</code> when it is finished with the parser. So if you
				2191	call this when there's already a pointer there, and you haven't freed
				2192	the memory associated with it, then you've probably just leaked
				2193	memory.
				2194	</div>
				2195
Elliott Hughes	33bf975	2021-08-10 17:33:34 -0700	[diff] [blame]	2196	<h4 id="XML_GetUserData">XML_GetUserData</h4>
				2197	<pre class="fcndec">
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	2198	void * XMLCALL
				2199	XML_GetUserData(XML_Parser p);
				2200	</pre>
				2201	<div class="fcndef">
				2202	This returns the user data pointer that gets passed to handlers.
				2203	It is actually implemented as a macro.
				2204	</div>
				2205
Elliott Hughes	33bf975	2021-08-10 17:33:34 -0700	[diff] [blame]	2206	<h4 id="XML_UseParserAsHandlerArg">XML_UseParserAsHandlerArg</h4>
				2207	<pre class="fcndec">
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	2208	void XMLCALL
				2209	XML_UseParserAsHandlerArg(XML_Parser p);
				2210	</pre>
				2211	<div class="fcndef">
				2212	After this is called, handlers receive the parser in their
				2213	<code>userData</code> arguments. The user data can still be obtained
				2214	using the <code><a href= "#XML_GetUserData"
				2215	>XML_GetUserData</a></code> function.
				2216	</div>
				2217
Elliott Hughes	33bf975	2021-08-10 17:33:34 -0700	[diff] [blame]	2218	<h4 id="XML_SetBase">XML_SetBase</h4>
				2219	<pre class="fcndec">
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	2220	enum XML_Status XMLCALL
				2221	XML_SetBase(XML_Parser p,
				2222	const XML_Char *base);
				2223	</pre>
				2224	<div class="fcndef">
				2225	Set the base to be used for resolving relative URIs in system
				2226	identifiers. The return value is <code>XML_STATUS_ERROR</code> if
				2227	there's no memory to store base, otherwise it's
				2228	<code>XML_STATUS_OK</code>.
				2229	</div>
				2230
Elliott Hughes	33bf975	2021-08-10 17:33:34 -0700	[diff] [blame]	2231	<h4 id="XML_GetBase">XML_GetBase</h4>
				2232	<pre class="fcndec">
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	2233	const XML_Char * XMLCALL
				2234	XML_GetBase(XML_Parser p);
				2235	</pre>
				2236	<div class="fcndef">
				2237	Return the base for resolving relative URIs.
				2238	</div>
				2239
Elliott Hughes	33bf975	2021-08-10 17:33:34 -0700	[diff] [blame]	2240	<h4 id="XML_GetSpecifiedAttributeCount">XML_GetSpecifiedAttributeCount</h4>
				2241	<pre class="fcndec">
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	2242	int XMLCALL
				2243	XML_GetSpecifiedAttributeCount(XML_Parser p);
				2244	</pre>
				2245	<div class="fcndef">
				2246	When attributes are reported to the start handler in the atts vector,
				2247	attributes that were explicitly set in the element occur before any
				2248	attributes that receive their value from default information in an
				2249	ATTLIST declaration. This function returns the number of attributes
				2250	that were explicitly set times two, thus giving the offset in the
				2251	<code>atts</code> array passed to the start tag handler of the first
				2252	attribute set due to defaults. It supplies information for the last
				2253	call to a start handler. If called inside a start handler, then that
				2254	means the current call.
				2255	</div>
				2256
Elliott Hughes	33bf975	2021-08-10 17:33:34 -0700	[diff] [blame]	2257	<h4 id="XML_GetIdAttributeIndex">XML_GetIdAttributeIndex</h4>
				2258	<pre class="fcndec">
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	2259	int XMLCALL
				2260	XML_GetIdAttributeIndex(XML_Parser p);
				2261	</pre>
				2262	<div class="fcndef">
				2263	Returns the index of the ID attribute passed in the atts array in the
				2264	last call to <code><a href= "#XML_StartElementHandler"
				2265	>XML_StartElementHandler</a></code>, or -1 if there is no ID
				2266	attribute. If called inside a start handler, then that means the
				2267	current call.
				2268	</div>
				2269
Elliott Hughes	33bf975	2021-08-10 17:33:34 -0700	[diff] [blame]	2270	<h4 id="XML_GetAttributeInfo">XML_GetAttributeInfo</h4>
				2271	<pre class="fcndec">
Elliott Hughes	35e432d	2012-09-09 14:23:38 -0700	[diff] [blame]	2272	const XML_AttrInfo * XMLCALL
				2273	XML_GetAttributeInfo(XML_Parser parser);
				2274	</pre>
				2275	<pre class="signature">
				2276	typedef struct {
				2277	XML_Index nameStart; /* Offset to beginning of the attribute name. */
				2278	XML_Index nameEnd; /* Offset after the attribute name's last byte. */
				2279	XML_Index valueStart; /* Offset to beginning of the attribute value. */
				2280	XML_Index valueEnd; /* Offset after the attribute value's last byte. */
				2281	} XML_AttrInfo;
				2282	</pre>
				2283	<div class="fcndef">
				2284	Returns an array of <code>XML_AttrInfo</code> structures for the
				2285	attribute/value pairs passed in the last call to the
				2286	<code>XML_StartElementHandler</code> that were specified
				2287	in the start-tag rather than defaulted. Each attribute/value pair counts
				2288	as 1; thus the number of entries in the array is
				2289	<code>XML_GetSpecifiedAttributeCount(parser) / 2</code>.
				2290	</div>
				2291
Elliott Hughes	33bf975	2021-08-10 17:33:34 -0700	[diff] [blame]	2292	<h4 id="XML_SetEncoding">XML_SetEncoding</h4>
				2293	<pre class="fcndec">
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	2294	enum XML_Status XMLCALL
				2295	XML_SetEncoding(XML_Parser p,
				2296	const XML_Char *encoding);
				2297	</pre>
				2298	<div class="fcndef">
				2299	Set the encoding to be used by the parser. It is equivalent to
				2300	passing a non-null encoding argument to the parser creation functions.
				2301	It must not be called after <code><a href= "#XML_Parse"
				2302	>XML_Parse</a></code> or <code><a href= "#XML_ParseBuffer"
				2303	>XML_ParseBuffer</a></code> have been called on the given parser.
				2304	Returns <code>XML_STATUS_OK</code> on success or
				2305	<code>XML_STATUS_ERROR</code> on error.
				2306	</div>
				2307
Elliott Hughes	33bf975	2021-08-10 17:33:34 -0700	[diff] [blame]	2308	<h4 id="XML_SetParamEntityParsing">XML_SetParamEntityParsing</h4>
				2309	<pre class="fcndec">
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	2310	int XMLCALL
				2311	XML_SetParamEntityParsing(XML_Parser p,
				2312	enum XML_ParamEntityParsing code);
				2313	</pre>
				2314	<div class="fcndef">
				2315	This enables parsing of parameter entities, including the external
				2316	parameter entity that is the external DTD subset, according to
				2317	<code>code</code>.
				2318	The choices for <code>code</code> are:
				2319	<ul>
				2320	<li><code>XML_PARAM_ENTITY_PARSING_NEVER</code></li>
				2321	<li><code>XML_PARAM_ENTITY_PARSING_UNLESS_STANDALONE</code></li>
				2322	<li><code>XML_PARAM_ENTITY_PARSING_ALWAYS</code></li>
				2323	</ul>
Elliott Hughes	35e432d	2012-09-09 14:23:38 -0700	[diff] [blame]	2324	<b>Note:</b> If <code>XML_SetParamEntityParsing</code> is called after
				2325	<code>XML_Parse</code> or <code>XML_ParseBuffer</code>, then it has
				2326	no effect and will always return 0.
				2327	</div>
				2328
Elliott Hughes	33bf975	2021-08-10 17:33:34 -0700	[diff] [blame]	2329	<h4 id="XML_SetHashSalt">XML_SetHashSalt</h4>
				2330	<pre class="fcndec">
Elliott Hughes	35e432d	2012-09-09 14:23:38 -0700	[diff] [blame]	2331	int XMLCALL
				2332	XML_SetHashSalt(XML_Parser p,
				2333	unsigned long hash_salt);
				2334	</pre>
				2335	<div class="fcndef">
				2336	Sets the hash salt to use for internal hash calculations.
				2337	Helps in preventing DoS attacks based on predicting hash
				2338	function behavior. In order to have an effect this must be called
				2339	before parsing has started. Returns 1 if successful, 0 when called
				2340	after <code>XML_Parse</code> or <code>XML_ParseBuffer</code>.
Elliott Hughes	33bf975	2021-08-10 17:33:34 -0700	[diff] [blame]	2341	<p><b>Note:</b> This call is optional, as the parser will auto-generate
Haibo Huang	40a7191	2019-10-11 11:13:39 -0700	[diff] [blame]	2342	a new random salt value if no value has been set at the start of parsing.</p>
Elliott Hughes	33bf975	2021-08-10 17:33:34 -0700	[diff] [blame]	2343	<p><b>Note:</b> One should not call <code>XML_SetHashSalt</code> with a
Paul Duffin	cee2349	2016-05-04 10:42:31 +0100	[diff] [blame]	2344	hash salt value of 0, as this value is used as sentinel value to indicate
				2345	that <code>XML_SetHashSalt</code> has <b>not</b> been called. Consequently
				2346	such a call will have no effect, even if it returns 1.</p>
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	2347	</div>
				2348
Elliott Hughes	33bf975	2021-08-10 17:33:34 -0700	[diff] [blame]	2349	<h4 id="XML_UseForeignDTD">XML_UseForeignDTD</h4>
				2350	<pre class="fcndec">
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	2351	enum XML_Error XMLCALL
				2352	XML_UseForeignDTD(XML_Parser parser, XML_Bool useDTD);
				2353	</pre>
				2354	<div class="fcndef">
				2355	<p>This function allows an application to provide an external subset
				2356	for the document type declaration for documents which do not specify
				2357	an external subset of their own. For documents which specify an
				2358	external subset in their DOCTYPE declaration, the application-provided
				2359	subset will be ignored. If the document does not contain a DOCTYPE
				2360	declaration at all and <code>useDTD</code> is true, the
				2361	application-provided subset will be parsed, but the
				2362	<code>startDoctypeDeclHandler</code> and
				2363	<code>endDoctypeDeclHandler</code> functions, if set, will not be
				2364	called. The setting of parameter entity parsing, controlled using
				2365	<code><a href= "#XML_SetParamEntityParsing"
				2366	>XML_SetParamEntityParsing</a></code>, will be honored.</p>
				2367
				2368	<p>The application-provided external subset is read by calling the
				2369	external entity reference handler set via <code><a href=
				2370	"#XML_SetExternalEntityRefHandler"
				2371	>XML_SetExternalEntityRefHandler</a></code> with both
				2372	<code>publicId</code> and <code>systemId</code> set to NULL.</p>
				2373
				2374	<p>If this function is called after parsing has begun, it returns
				2375	<code>XML_ERROR_CANT_CHANGE_FEATURE_ONCE_PARSING</code> and ignores
				2376	<code>useDTD</code>. If called when Expat has been compiled without
				2377	DTD support, it returns
				2378	<code>XML_ERROR_FEATURE_REQUIRES_XML_DTD</code>. Otherwise, it
				2379	returns <code>XML_ERROR_NONE</code>.</p>
				2380
				2381	<p><b>Note:</b> For the purpose of checking WFC: Entity Declared, passing
				2382	<code>useDTD == XML_TRUE</code> will make the parser behave as if
				2383	the document had a DTD with an external subset. This holds true even if
				2384	the external entity reference handler returns without action.</p>
				2385	</div>
				2386
Elliott Hughes	33bf975	2021-08-10 17:33:34 -0700	[diff] [blame]	2387	<h4 id="XML_SetReturnNSTriplet">XML_SetReturnNSTriplet</h4>
				2388	<pre class="fcndec">
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	2389	void XMLCALL
				2390	XML_SetReturnNSTriplet(XML_Parser parser,
				2391	int do_nst);
				2392	</pre>
				2393	<div class="fcndef">
				2394	<p>
				2395	This function only has an effect when using a parser created with
				2396	<code><a href= "#XML_ParserCreateNS" >XML_ParserCreateNS</a></code>,
				2397	i.e. when namespace processing is in effect. The <code>do_nst</code>
				2398	sets whether or not prefixes are returned with names qualified with a
				2399	namespace prefix. If this function is called with <code>do_nst</code>
				2400	non-zero, then afterwards namespace qualified names (that is qualified
				2401	with a prefix as opposed to belonging to a default namespace) are
				2402	returned as a triplet with the three parts separated by the namespace
				2403	separator specified when the parser was created. The order of
				2404	returned parts is URI, local name, and prefix.</p> <p>If
				2405	<code>do_nst</code> is zero, then namespaces are reported in the
				2406	default manner, URI then local_name separated by the namespace
				2407	separator.</p>
				2408	</div>
				2409
Elliott Hughes	33bf975	2021-08-10 17:33:34 -0700	[diff] [blame]	2410	<h4 id="XML_DefaultCurrent">XML_DefaultCurrent</h4>
				2411	<pre class="fcndec">
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	2412	void XMLCALL
				2413	XML_DefaultCurrent(XML_Parser parser);
				2414	</pre>
				2415	<div class="fcndef">
				2416	This can be called within a handler for a start element, end element,
				2417	processing instruction or character data. It causes the corresponding
				2418	markup to be passed to the default handler set by <code><a
				2419	href="#XML_SetDefaultHandler" >XML_SetDefaultHandler</a></code> or
				2420	<code><a href="#XML_SetDefaultHandlerExpand"
				2421	>XML_SetDefaultHandlerExpand</a></code>. It does nothing if there is
				2422	not a default handler.
				2423	</div>
				2424
Elliott Hughes	33bf975	2021-08-10 17:33:34 -0700	[diff] [blame]	2425	<h4 id="XML_ExpatVersion">XML_ExpatVersion</h4>
				2426	<pre class="fcndec">
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	2427	XML_LChar * XMLCALL
				2428	XML_ExpatVersion();
				2429	</pre>
				2430	<div class="fcndef">
				2431	Return the library version as a string (e.g. <code>"expat_1.95.1"</code>).
				2432	</div>
				2433
Elliott Hughes	33bf975	2021-08-10 17:33:34 -0700	[diff] [blame]	2434	<h4 id="XML_ExpatVersionInfo">XML_ExpatVersionInfo</h4>
				2435	<pre class="fcndec">
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	2436	struct XML_Expat_Version XMLCALL
				2437	XML_ExpatVersionInfo();
				2438	</pre>
				2439	<pre class="signature">
				2440	typedef struct {
				2441	int major;
				2442	int minor;
				2443	int micro;
				2444	} XML_Expat_Version;
				2445	</pre>
				2446	<div class="fcndef">
				2447	Return the library version information as a structure.
				2448	Some macros are also defined that support compile-time tests of the
				2449	library version:
				2450	<ul>
				2451	<li><code>XML_MAJOR_VERSION</code></li>
				2452	<li><code>XML_MINOR_VERSION</code></li>
				2453	<li><code>XML_MICRO_VERSION</code></li>
				2454	</ul>
				2455	Testing these constants is currently the best way to determine if
				2456	particular parts of the Expat API are available.
				2457	</div>
				2458
Elliott Hughes	33bf975	2021-08-10 17:33:34 -0700	[diff] [blame]	2459	<h4 id="XML_GetFeatureList">XML_GetFeatureList</h4>
				2460	<pre class="fcndec">
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	2461	const XML_Feature * XMLCALL
				2462	XML_GetFeatureList();
				2463	</pre>
				2464	<pre class="signature">
				2465	enum XML_FeatureEnum {
				2466	XML_FEATURE_END = 0,
				2467	XML_FEATURE_UNICODE,
				2468	XML_FEATURE_UNICODE_WCHAR_T,
				2469	XML_FEATURE_DTD,
				2470	XML_FEATURE_CONTEXT_BYTES,
				2471	XML_FEATURE_MIN_SIZE,
				2472	XML_FEATURE_SIZEOF_XML_CHAR,
Elliott Hughes	d07d5a7	2009-09-25 16:04:37 -0700	[diff] [blame]	2473	XML_FEATURE_SIZEOF_XML_LCHAR,
				2474	XML_FEATURE_NS,
				2475	XML_FEATURE_LARGE_SIZE
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	2476	};
				2477
				2478	typedef struct {
				2479	enum XML_FeatureEnum feature;
				2480	XML_LChar *name;
				2481	long int value;
				2482	} XML_Feature;
				2483	</pre>
				2484	<div class="fcndef">
				2485	<p>Returns a list of "feature" records, providing details on how
				2486	Expat was configured at compile time. Most applications should not
				2487	need to worry about this, but this information is otherwise not
				2488	available from Expat. This function allows code that does need to
				2489	check these features to do so at runtime.</p>
				2490
				2491	<p>The return value is an array of <code>XML_Feature</code>,
				2492	terminated by a record with a <code>feature</code> of
				2493	<code>XML_FEATURE_END</code> and <code>name</code> of NULL,
				2494	identifying the feature-test macros Expat was compiled with. Since an
				2495	application that requires this kind of information needs to determine
				2496	the type of character the <code>name</code> points to, records for the
				2497	<code>XML_FEATURE_SIZEOF_XML_CHAR</code> and
				2498	<code>XML_FEATURE_SIZEOF_XML_LCHAR</code> will be located at the
				2499	beginning of the list, followed by <code>XML_FEATURE_UNICODE</code>
				2500	and <code>XML_FEATURE_UNICODE_WCHAR_T</code>, if they are present at
				2501	all.</p>
				2502
				2503	<p>Some features have an associated value. If there isn't an
				2504	associated value, the <code>value</code> field is set to 0. At this
				2505	time, the following features have been defined to have values:</p>
				2506
				2507	<dl>
				2508	<dt><code>XML_FEATURE_SIZEOF_XML_CHAR</code></dt>
				2509	<dd>The number of bytes occupied by one <code>XML_Char</code>
				2510	character.</dd>
				2511	<dt><code>XML_FEATURE_SIZEOF_XML_LCHAR</code></dt>
				2512	<dd>The number of bytes occupied by one <code>XML_LChar</code>
				2513	character.</dd>
				2514	<dt><code>XML_FEATURE_CONTEXT_BYTES</code></dt>
				2515	<dd>The maximum number of characters of context which can be
				2516	reported by <code><a href= "#XML_GetInputContext"
				2517	>XML_GetInputContext</a></code>.</dd>
				2518	</dl>
				2519	</div>
				2520
Elliott Hughes	33bf975	2021-08-10 17:33:34 -0700	[diff] [blame]	2521	<h4 id="XML_FreeContentModel">XML_FreeContentModel</h4>
				2522	<pre class="fcndec">
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	2523	void XMLCALL
				2524	XML_FreeContentModel(XML_Parser parser, XML_Content *model);
				2525	</pre>
				2526	<div class="fcndef">
				2527	Function to deallocate the <code>model</code> argument passed to the
				2528	<code>XML_ElementDeclHandler</code> callback set using <code><a
				2529	href="#XML_SetElementDeclHandler" >XML_ElementDeclHandler</a></code>.
				2530	This function should not be used for any other purpose.
				2531	</div>
				2532
				2533	<p>The following functions allow external code to share the memory
				2534	allocator an <code>XML_Parser</code> has been configured to use. This
				2535	is especially useful for third-party libraries that interact with a
				2536	parser object created by application code, or heavily layered
				2537	applications. This can be essential when using dynamically loaded
				2538	libraries which use different C standard libraries (this can happen on
				2539	Windows, at least).</p>
				2540
Elliott Hughes	33bf975	2021-08-10 17:33:34 -0700	[diff] [blame]	2541	<h4 id="XML_MemMalloc">XML_MemMalloc</h4>
				2542	<pre class="fcndec">
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	2543	void * XMLCALL
				2544	XML_MemMalloc(XML_Parser parser, size_t size);
				2545	</pre>
				2546	<div class="fcndef">
				2547	Allocate <code>size</code> bytes of memory using the allocator the
				2548	<code>parser</code> object has been configured to use. Returns a
				2549	pointer to the memory or NULL on failure. Memory allocated in this
				2550	way must be freed using <code><a href="#XML_MemFree"
				2551	>XML_MemFree</a></code>.
				2552	</div>
				2553
Elliott Hughes	33bf975	2021-08-10 17:33:34 -0700	[diff] [blame]	2554	<h4 id="XML_MemRealloc">XML_MemRealloc</h4>
				2555	<pre class="fcndec">
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	2556	void * XMLCALL
				2557	XML_MemRealloc(XML_Parser parser, void *ptr, size_t size);
				2558	</pre>
				2559	<div class="fcndef">
				2560	Allocate <code>size</code> bytes of memory using the allocator the
				2561	<code>parser</code> object has been configured to use.
				2562	<code>ptr</code> must point to a block of memory allocated by <code><a
				2563	href="#XML_MemMalloc" >XML_MemMalloc</a></code> or
				2564	<code>XML_MemRealloc</code>, or be NULL. This function tries to
				2565	expand the block pointed to by <code>ptr</code> if possible. Returns
				2566	a pointer to the memory or NULL on failure. On success, the original
				2567	block has either been expanded or freed. On failure, the original
				2568	block has not been freed; the caller is responsible for freeing the
				2569	original block. Memory allocated in this way must be freed using
				2570	<code><a href="#XML_MemFree"
				2571	>XML_MemFree</a></code>.
				2572	</div>
				2573
Elliott Hughes	33bf975	2021-08-10 17:33:34 -0700	[diff] [blame]	2574	<h4 id="XML_MemFree">XML_MemFree</h4>
				2575	<pre class="fcndec">
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	2576	void XMLCALL
				2577	XML_MemFree(XML_Parser parser, void *ptr);
				2578	</pre>
				2579	<div class="fcndef">
				2580	Free a block of memory pointed to by <code>ptr</code>. The block must
				2581	have been allocated by <code><a href="#XML_MemMalloc"
				2582	>XML_MemMalloc</a></code> or <code>XML_MemRealloc</code>, or be NULL.
				2583	</div>
				2584
				2585	<hr />
Elliott Hughes	33bf975	2021-08-10 17:33:34 -0700	[diff] [blame]	2586
				2587	<div class="footer">
				2588	Found a bug in the documentation?
				2589	<a href="https://github.com/libexpat/libexpat/issues">Please file a bug report.</a>
				2590	</div>
				2591
The Android Open Source Project	b80e287	2009-03-03 19:29:30 -0800	[diff] [blame]	2592	</div>
				2593	</body>
				2594	</html>