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Daniel Veillard598bec32003-07-06 10:02:03 +00005 <title>The XML C parser and toolkit of Gnome</title>
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Daniel Veillard598bec32003-07-06 10:02:03 +000011<h1 align="center">The XML C parser and toolkit of Gnome</h1>
Daniel Veillardb05deb71999-08-10 19:04:08 +000012
Daniel Veillard9c466822001-10-25 12:03:39 +000013<h1>Note: this is the flat content of the <a href="index.html">web
14site</a></h1>
15
Daniel Veillardc9484202001-10-24 12:35:52 +000016<h1 style="text-align: center">libxml, a.k.a. gnome-xml</h1>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +000017
18<p></p>
Daniel Veillard9c466822001-10-25 12:03:39 +000019
Daniel Veillard7ebac022004-02-25 22:36:35 +000020<p
21style="text-align: right; font-style: italic; font-size: 10pt">"Programming
22with libxml2 is like the thrilling embrace of an exotic stranger." <a
23href="http://diveintomark.org/archives/2004/02/18/libxml2">Mark
24Pilgrim</a></p>
25
Daniel Veillard598bec32003-07-06 10:02:03 +000026<p>Libxml2 is the XML C parser and toolkit developed for the Gnome project
Daniel Veillard23a52c52003-08-18 10:01:18 +000027(but usable outside of the Gnome platform), it is free software available
Daniel Veillardeec1ae92003-09-09 13:11:01 +000028under the <a href="http://www.opensource.org/licenses/mit-license.html">MIT
29License</a>. XML itself is a metalanguage to design markup languages, i.e.
30text language where semantic and structure are added to the content using
31extra "markup" information enclosed between angle brackets. HTML is the most
32well-known markup language. Though the library is written in C <a
33href="python.html">a variety of language bindings</a> make it available in
34other environments.</p>
Daniel Veillard9c466822001-10-25 12:03:39 +000035
Daniel Veillard710823b2003-03-04 10:05:52 +000036<p>Libxml2 is known to be very portable, the library should build and work
37without serious troubles on a variety of systems (Linux, Unix, Windows,
38CygWin, MacOS, MacOS X, RISC Os, OS/2, VMS, QNX, MVS, ...)</p>
39
Daniel Veillard9c466822001-10-25 12:03:39 +000040<p>Libxml2 implements a number of existing standards related to markup
41languages:</p>
Daniel Veillard2f4dfc41999-09-24 14:03:48 +000042<ul>
Daniel Veillard9c466822001-10-25 12:03:39 +000043 <li>the XML standard: <a
44 href="http://www.w3.org/TR/REC-xml">http://www.w3.org/TR/REC-xml</a></li>
45 <li>Namespaces in XML: <a
46 href="http://www.w3.org/TR/REC-xml-names/">http://www.w3.org/TR/REC-xml-names/</a></li>
47 <li>XML Base: <a
48 href="http://www.w3.org/TR/xmlbase/">http://www.w3.org/TR/xmlbase/</a></li>
Daniel Veillardaf43f632002-03-08 15:05:20 +000049 <li><a href="http://www.cis.ohio-state.edu/rfc/rfc2396.txt">RFC 2396</a> :
50 Uniform Resource Identifiers <a
Daniel Veillard9c466822001-10-25 12:03:39 +000051 href="http://www.ietf.org/rfc/rfc2396.txt">http://www.ietf.org/rfc/rfc2396.txt</a></li>
52 <li>XML Path Language (XPath) 1.0: <a
53 href="http://www.w3.org/TR/xpath">http://www.w3.org/TR/xpath</a></li>
54 <li>HTML4 parser: <a
55 href="http://www.w3.org/TR/html401/">http://www.w3.org/TR/html401/</a></li>
Daniel Veillard23a52c52003-08-18 10:01:18 +000056 <li>XML Pointer Language (XPointer) Version 1.0: <a
Daniel Veillard9c466822001-10-25 12:03:39 +000057 href="http://www.w3.org/TR/xptr">http://www.w3.org/TR/xptr</a></li>
58 <li>XML Inclusions (XInclude) Version 1.0: <a
59 href="http://www.w3.org/TR/xinclude/">http://www.w3.org/TR/xinclude/</a></li>
Daniel Veillard23a52c52003-08-18 10:01:18 +000060 <li>ISO-8859-x encodings, as well as <a
Daniel Veillard9c466822001-10-25 12:03:39 +000061 href="http://www.cis.ohio-state.edu/rfc/rfc2044.txt">rfc2044</a> [UTF-8]
62 and <a href="http://www.cis.ohio-state.edu/rfc/rfc2781.txt">rfc2781</a>
Daniel Veillard23a52c52003-08-18 10:01:18 +000063 [UTF-16] Unicode encodings, and more if using iconv support</li>
Daniel Veillard9c466822001-10-25 12:03:39 +000064 <li>part of SGML Open Technical Resolution TR9401:1997</li>
65 <li>XML Catalogs Working Draft 06 August 2001: <a
66 href="http://www.oasis-open.org/committees/entity/spec-2001-08-06.html">http://www.oasis-open.org/committees/entity/spec-2001-08-06.html</a></li>
Daniel Veillard5c396542002-03-15 07:57:50 +000067 <li>Canonical XML Version 1.0: <a
68 href="http://www.w3.org/TR/xml-c14n">http://www.w3.org/TR/xml-c14n</a>
Daniel Veillard2d347fa2002-03-17 10:34:11 +000069 and the Exclusive XML Canonicalization CR draft <a
70 href="http://www.w3.org/TR/xml-exc-c14n">http://www.w3.org/TR/xml-exc-c14n</a></li>
Daniel Veillard758c5312003-12-15 11:51:25 +000071 <li>Relax NG, ISO/IEC 19757-2:2003, <a
Daniel Veillard17bed982003-02-24 20:11:43 +000072 href="http://www.oasis-open.org/committees/relax-ng/spec-20011203.html">http://www.oasis-open.org/committees/relax-ng/spec-20011203.html</a></li>
Daniel Veillardf83a2c72003-04-08 13:48:40 +000073 <li>W3C XML Schemas Part 2: Datatypes <a
74 href="http://www.w3.org/TR/2001/REC-xmlschema-2-20010502/">REC 02 May
Daniel Veillard7ecced52003-12-18 14:22:09 +000075 2001</a></li>
Daniel Veillardeca726d2004-04-18 21:47:34 +000076 <li>W3C <a href="http://www.w3.org/TR/xml-id/">xml:id</a> Working Draft 7
77 April 2004</li>
Daniel Veillard96984452000-08-31 13:50:12 +000078</ul>
79
Daniel Veillard560c2a42003-07-06 21:13:49 +000080<p>In most cases libxml2 tries to implement the specifications in a
Daniel Veillard7c4eb632004-04-19 21:29:12 +000081relatively strictly compliant way. As of release 2.4.16, libxml2 passed all
Daniel Veillard560c2a42003-07-06 21:13:49 +0000821800+ tests from the <a
Daniel Veillarda5393562002-02-20 11:40:49 +000083href="http://www.oasis-open.org/committees/xml-conformance/">OASIS XML Tests
84Suite</a>.</p>
Daniel Veillard5b16f582002-02-20 11:38:46 +000085
Daniel Veillard0b28e882002-07-24 23:47:05 +000086<p>To some extent libxml2 provides support for the following additional
87specifications but doesn't claim to implement them completely:</p>
Daniel Veillard9c466822001-10-25 12:03:39 +000088<ul>
89 <li>Document Object Model (DOM) <a
90 href="http://www.w3.org/TR/DOM-Level-2-Core/">http://www.w3.org/TR/DOM-Level-2-Core/</a>
Daniel Veillardd4cfcef2004-05-06 18:55:27 +000091 the document model, but it doesn't implement the API itself, gdome2 does
92 this on top of libxml2</li>
Daniel Veillardaf43f632002-03-08 15:05:20 +000093 <li><a href="http://www.cis.ohio-state.edu/rfc/rfc959.txt">RFC 959</a> :
Daniel Veillard8a469172003-06-12 16:05:07 +000094 libxml2 implements a basic FTP client code</li>
Daniel Veillardaf43f632002-03-08 15:05:20 +000095 <li><a href="http://www.cis.ohio-state.edu/rfc/rfc1945.txt">RFC 1945</a> :
96 HTTP/1.0, again a basic HTTP client code</li>
Daniel Veillard7c4eb632004-04-19 21:29:12 +000097 <li>SAX: a SAX2 like interface and a minimal SAX1 implementation compatible
98 with early expat versions</li>
Daniel Veillard9c466822001-10-25 12:03:39 +000099</ul>
100
Daniel Veillardf83a2c72003-04-08 13:48:40 +0000101<p>A partial implementation of <a
102href="http://www.w3.org/TR/2001/REC-xmlschema-1-20010502/">XML Schemas Part
1031: Structure</a> is being worked on but it would be far too early to make any
104conformance statement about it at the moment.</p>
Daniel Veillarde6d8e202002-05-02 06:11:10 +0000105
Daniel Veillard96984452000-08-31 13:50:12 +0000106<p>Separate documents:</p>
107<ul>
Daniel Veillardaf43f632002-03-08 15:05:20 +0000108 <li><a href="http://xmlsoft.org/XSLT/">the libxslt page</a> providing an
Daniel Veillard2d347fa2002-03-17 10:34:11 +0000109 implementation of XSLT 1.0 and common extensions like EXSLT for
110 libxml2</li>
Daniel Veillardc6271d22001-10-27 07:50:58 +0000111 <li><a href="http://www.cs.unibo.it/~casarini/gdome2/">the gdome2 page</a>
Daniel Veillard2d347fa2002-03-17 10:34:11 +0000112 : a standard DOM2 implementation for libxml2</li>
113 <li><a href="http://www.aleksey.com/xmlsec/">the XMLSec page</a>: an
114 implementation of <a href="http://www.w3.org/TR/xmldsig-core/">W3C XML
115 Digital Signature</a> for libxml2</li>
Daniel Veillarde6d8e202002-05-02 06:11:10 +0000116 <li>also check the related links section below for more related and active
117 projects.</li>
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000118</ul>
Daniel Veillard252004d2004-03-23 12:32:32 +0000119<!----------------<p>Results of the <a
Daniel Veillard806cada2003-03-19 21:58:59 +0000120href="http://xmlbench.sourceforge.net/results/benchmark/index.html">xmlbench
Daniel Veillard31ae4622004-02-16 07:45:44 +0000121benchmark</a> on sourceforge February 2004 (smaller is better):</p>
Daniel Veillardd8da01c2003-03-24 15:58:23 +0000122
Daniel Veillard31ae4622004-02-16 07:45:44 +0000123<p align="center"><img src="benchmark.png"
Daniel Veillardd8da01c2003-03-24 15:58:23 +0000124alt="benchmark results for Expat Xerces libxml2 Oracle and Sun toolkits"></p>
Daniel Veillardcf80b782004-03-07 19:32:19 +0000125-------------->
Daniel Veillard806cada2003-03-19 21:58:59 +0000126
Daniel Veillard252004d2004-03-23 12:32:32 +0000127
Daniel Veillarde1662542002-08-28 11:50:59 +0000128<p>Logo designed by <a href="mailto:liyanage@access.ch">Marc Liyanage</a>.</p>
129
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000130<h2><a name="Introducti">Introduction</a></h2>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000131
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000132<p>This document describes libxml, the <a
Daniel Veillard560c2a42003-07-06 21:13:49 +0000133href="http://www.w3.org/XML/">XML</a> C parser and toolkit developed for the
134<a href="http://www.gnome.org/">Gnome</a> project. <a
Daniel Veillardec78c0f2000-08-25 10:25:23 +0000135href="http://www.w3.org/XML/">XML is a standard</a> for building tag-based
136structured documents/data.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000137
Daniel Veillard0142b842000-01-14 14:45:24 +0000138<p>Here are some key points about libxml:</p>
139<ul>
Daniel Veillard8a469172003-06-12 16:05:07 +0000140 <li>Libxml2 exports Push (progressive) and Pull (blocking) type parser
Daniel Veillard2d347fa2002-03-17 10:34:11 +0000141 interfaces for both XML and HTML.</li>
Daniel Veillard8a469172003-06-12 16:05:07 +0000142 <li>Libxml2 can do DTD validation at parse time, using a parsed document
Daniel Veillard91e9d582001-02-26 07:31:12 +0000143 instance, or with an arbitrary DTD.</li>
Daniel Veillard8a469172003-06-12 16:05:07 +0000144 <li>Libxml2 includes complete <a
Daniel Veillard8c2ecaf2001-07-10 17:53:07 +0000145 href="http://www.w3.org/TR/xpath">XPath</a>, <a
146 href="http://www.w3.org/TR/xptr">XPointer</a> and <a
147 href="http://www.w3.org/TR/xinclude">XInclude</a> implementations.</li>
Daniel Veillardec78c0f2000-08-25 10:25:23 +0000148 <li>It is written in plain C, making as few assumptions as possible, and
Daniel Veillard189446d2000-10-13 10:23:06 +0000149 sticking closely to ANSI C/POSIX for easy embedding. Works on
Daniel Veillardab8500d2000-10-15 21:06:19 +0000150 Linux/Unix/Windows, ported to a number of other platforms.</li>
Daniel Veillard63d83142002-05-20 06:51:05 +0000151 <li>Basic support for HTTP and FTP client allowing applications to fetch
Daniel Veillard0b28e882002-07-24 23:47:05 +0000152 remote resources.</li>
Daniel Veillard91e9d582001-02-26 07:31:12 +0000153 <li>The design is modular, most of the extensions can be compiled out.</li>
Daniel Veillard63d83142002-05-20 06:51:05 +0000154 <li>The internal document representation is as close as possible to the <a
Daniel Veillard0142b842000-01-14 14:45:24 +0000155 href="http://www.w3.org/DOM/">DOM</a> interfaces.</li>
Daniel Veillard560c2a42003-07-06 21:13:49 +0000156 <li>Libxml2 also has a <a
157 href="http://www.megginson.com/SAX/index.html">SAX like interface</a>;
158 the interface is designed to be compatible with <a
Daniel Veillard402e8c82000-02-29 22:57:47 +0000159 href="http://www.jclark.com/xml/expat.html">Expat</a>.</li>
Daniel Veillardc575b992002-02-08 13:28:40 +0000160 <li>This library is released under the <a
161 href="http://www.opensource.org/licenses/mit-license.html">MIT
Daniel Veillard0b28e882002-07-24 23:47:05 +0000162 License</a>. See the Copyright file in the distribution for the precise
Daniel Veillardc575b992002-02-08 13:28:40 +0000163 wording.</li>
Daniel Veillard0142b842000-01-14 14:45:24 +0000164</ul>
Daniel Veillardccb09631998-10-27 06:21:04 +0000165
Daniel Veillarde0c1d722001-03-21 10:28:36 +0000166<p>Warning: unless you are forced to because your application links with a
Daniel Veillard2d347fa2002-03-17 10:34:11 +0000167Gnome-1.X library requiring it, <strong><span
Daniel Veillarde0c1d722001-03-21 10:28:36 +0000168style="background-color: #FF0000">Do Not Use libxml1</span></strong>, use
169libxml2</p>
170
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000171<h2><a name="FAQ">FAQ</a></h2>
172
Daniel Veillard0b28e882002-07-24 23:47:05 +0000173<p>Table of Contents:</p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000174<ul>
Daniel Veillard63d83142002-05-20 06:51:05 +0000175 <li><a href="FAQ.html#License">License(s)</a></li>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000176 <li><a href="FAQ.html#Installati">Installation</a></li>
177 <li><a href="FAQ.html#Compilatio">Compilation</a></li>
178 <li><a href="FAQ.html#Developer">Developer corner</a></li>
179</ul>
180
Daniel Veillard63d83142002-05-20 06:51:05 +0000181<h3><a name="License">License</a>(s)</h3>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000182<ol>
183 <li><em>Licensing Terms for libxml</em>
Daniel Veillard8a469172003-06-12 16:05:07 +0000184 <p>libxml2 is released under the <a
Daniel Veillardc575b992002-02-08 13:28:40 +0000185 href="http://www.opensource.org/licenses/mit-license.html">MIT
Daniel Veillard0b28e882002-07-24 23:47:05 +0000186 License</a>; see the file Copyright in the distribution for the precise
Daniel Veillardc575b992002-02-08 13:28:40 +0000187 wording</p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000188 </li>
Daniel Veillard8a469172003-06-12 16:05:07 +0000189 <li><em>Can I embed libxml2 in a proprietary application ?</em>
Daniel Veillard42766c02002-08-22 20:52:17 +0000190 <p>Yes. The MIT License allows you to keep proprietary the changes you
191 made to libxml, but it would be graceful to send-back bug fixes and
192 improvements as patches for possible incorporation in the main
Daniel Veillard0b28e882002-07-24 23:47:05 +0000193 development tree.</p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000194 </li>
195</ol>
196
197<h3><a name="Installati">Installation</a></h3>
198<ol>
Daniel Veillard560c2a42003-07-06 21:13:49 +0000199 <li><strong><span style="background-color: #FF0000">Do Not Use
200 libxml1</span></strong>, use libxml2</li>
Daniel Veillardaf43f632002-03-08 15:05:20 +0000201 <li><em>Where can I get libxml</em> ?
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000202 <p>The original distribution comes from <a
203 href="ftp://rpmfind.net/pub/libxml/">rpmfind.net</a> or <a
Daniel Veillard024f1992003-12-10 16:43:49 +0000204 href="ftp://ftp.gnome.org/pub/GNOME/sources/libxml2/2.6/">gnome.org</a></p>
Daniel Veillard63d83142002-05-20 06:51:05 +0000205 <p>Most Linux and BSD distributions include libxml, this is probably the
Daniel Veillard0b28e882002-07-24 23:47:05 +0000206 safer way for end-users to use libxml.</p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000207 <p>David Doolin provides precompiled Windows versions at <a
208 href="http://www.ce.berkeley.edu/~doolin/code/libxmlwin32/ ">http://www.ce.berkeley.edu/~doolin/code/libxmlwin32/</a></p>
209 </li>
210 <li><em>I see libxml and libxml2 releases, which one should I install ?</em>
211 <ul>
Daniel Veillard42766c02002-08-22 20:52:17 +0000212 <li>If you are not constrained by backward compatibility issues with
213 existing applications, install libxml2 only</li>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000214 <li>If you are not doing development, you can safely install both.
Daniel Veillard0b28e882002-07-24 23:47:05 +0000215 Usually the packages <a
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000216 href="http://rpmfind.net/linux/RPM/libxml.html">libxml</a> and <a
217 href="http://rpmfind.net/linux/RPM/libxml2.html">libxml2</a> are
Daniel Veillard0b28e882002-07-24 23:47:05 +0000218 compatible (this is not the case for development packages).</li>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000219 <li>If you are a developer and your system provides separate packaging
220 for shared libraries and the development components, it is possible
221 to install libxml and libxml2, and also <a
222 href="http://rpmfind.net/linux/RPM/libxml-devel.html">libxml-devel</a>
223 and <a
224 href="http://rpmfind.net/linux/RPM/libxml2-devel.html">libxml2-devel</a>
225 too for libxml2 &gt;= 2.3.0</li>
226 <li>If you are developing a new application, please develop against
227 libxml2(-devel)</li>
228 </ul>
229 </li>
Daniel Veillard0b28e882002-07-24 23:47:05 +0000230 <li><em>I can't install the libxml package, it conflicts with libxml0</em>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000231 <p>You probably have an old libxml0 package used to provide the shared
Daniel Veillard42766c02002-08-22 20:52:17 +0000232 library for libxml.so.0, you can probably safely remove it. The libxml
233 packages provided on <a
Daniel Veillard0b28e882002-07-24 23:47:05 +0000234 href="ftp://rpmfind.net/pub/libxml/">rpmfind.net</a> provide
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000235 libxml.so.0</p>
236 </li>
237 <li><em>I can't install the libxml(2) RPM package due to failed
Daniel Veillard63d83142002-05-20 06:51:05 +0000238 dependencies</em>
239 <p>The most generic solution is to re-fetch the latest src.rpm , and
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000240 rebuild it locally with</p>
Daniel Veillard0b28e882002-07-24 23:47:05 +0000241 <p><code>rpm --rebuild libxml(2)-xxx.src.rpm</code>.</p>
Daniel Veillard42766c02002-08-22 20:52:17 +0000242 <p>If everything goes well it will generate two binary rpm packages (one
243 providing the shared libs and xmllint, and the other one, the -devel
244 package, providing includes, static libraries and scripts needed to build
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000245 applications with libxml(2)) that you can install locally.</p>
246 </li>
247</ol>
248
249<h3><a name="Compilatio">Compilation</a></h3>
250<ol>
Daniel Veillard8a469172003-06-12 16:05:07 +0000251 <li><em>What is the process to compile libxml2 ?</em>
252 <p>As most UNIX libraries libxml2 follows the "standard":</p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000253 <p><code>gunzip -c xxx.tar.gz | tar xvf -</code></p>
254 <p><code>cd libxml-xxxx</code></p>
255 <p><code>./configure --help</code></p>
256 <p>to see the options, then the compilation/installation proper</p>
257 <p><code>./configure [possible options]</code></p>
258 <p><code>make</code></p>
259 <p><code>make install</code></p>
Daniel Veillard0b28e882002-07-24 23:47:05 +0000260 <p>At that point you may have to rerun ldconfig or a similar utility to
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000261 update your list of installed shared libs.</p>
262 </li>
Daniel Veillard8a469172003-06-12 16:05:07 +0000263 <li><em>What other libraries are needed to compile/install libxml2 ?</em>
264 <p>Libxml2 does not require any other library, the normal C ANSI API
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000265 should be sufficient (please report any violation to this rule you may
266 find).</p>
Daniel Veillard8a469172003-06-12 16:05:07 +0000267 <p>However if found at configuration time libxml2 will detect and use the
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000268 following libs:</p>
269 <ul>
Daniel Veillardaf43f632002-03-08 15:05:20 +0000270 <li><a href="http://www.info-zip.org/pub/infozip/zlib/">libz</a> : a
Daniel Veillard0b28e882002-07-24 23:47:05 +0000271 highly portable and available widely compression library.</li>
272 <li>iconv: a powerful character encoding conversion library. It is
273 included by default in recent glibc libraries, so it doesn't need to
274 be installed specifically on Linux. It now seems a <a
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000275 href="http://www.opennc.org/onlinepubs/7908799/xsh/iconv.html">part
276 of the official UNIX</a> specification. Here is one <a
Daniel Veillarddad3f682002-11-17 16:47:27 +0000277 href="http://www.gnu.org/software/libiconv/">implementation of the
278 library</a> which source can be found <a
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000279 href="ftp://ftp.ilog.fr/pub/Users/haible/gnu/">here</a>.</li>
280 </ul>
281 </li>
Daniel Veillard0b28e882002-07-24 23:47:05 +0000282 <li><em>Make check fails on some platforms</em>
Daniel Veillard42766c02002-08-22 20:52:17 +0000283 <p>Sometimes the regression tests' results don't completely match the
284 value produced by the parser, and the makefile uses diff to print the
285 delta. On some platforms the diff return breaks the compilation process;
286 if the diff is small this is probably not a serious problem.</p>
Daniel Veillard0b28e882002-07-24 23:47:05 +0000287 <p>Sometimes (especially on Solaris) make checks fail due to limitations
Daniel Veillarde46182c2002-02-12 14:29:11 +0000288 in make. Try using GNU-make instead.</p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000289 </li>
290 <li><em>I use the CVS version and there is no configure script</em>
Daniel Veillard42766c02002-08-22 20:52:17 +0000291 <p>The configure script (and other Makefiles) are generated. Use the
292 autogen.sh script to regenerate the configure script and Makefiles,
293 like:</p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000294 <p><code>./autogen.sh --prefix=/usr --disable-shared</code></p>
295 </li>
296 <li><em>I have troubles when running make tests with gcc-3.0</em>
297 <p>It seems the initial release of gcc-3.0 has a problem with the
298 optimizer which miscompiles the URI module. Please use another
Daniel Veillard0b28e882002-07-24 23:47:05 +0000299 compiler.</p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000300 </li>
301</ol>
302
303<h3><a name="Developer">Developer</a> corner</h3>
304<ol>
Daniel Veillard93d95252003-04-29 20:25:40 +0000305 <li><em>Troubles compiling or linking programs using libxml2</em>
306 <p>Usually the problem comes from the fact that the compiler doesn't get
307 the right compilation or linking flags. There is a small shell script
308 <code>xml2-config</code> which is installed as part of libxml2 usual
Daniel Veillard560c2a42003-07-06 21:13:49 +0000309 install process which provides those flags. Use</p>
Daniel Veillard93d95252003-04-29 20:25:40 +0000310 <p><code>xml2-config --cflags</code></p>
311 <p>to get the compilation flags and</p>
312 <p><code>xml2-config --libs</code></p>
313 <p>to get the linker flags. Usually this is done directly from the
314 Makefile as:</p>
315 <p><code>CFLAGS=`xml2-config --cflags`</code></p>
316 <p><code>LIBS=`xml2-config --libs`</code></p>
317 </li>
William M. Brack99906ad2005-01-09 17:02:42 +0000318 <li><em>I want to install my own copy of libxml2 in my home directory and link
319 my programs against it, but it doesn't work</em>
320 <p>There are many different ways to accomplish this. Here is one way to
321 do this under Linux. Suppose your home directory is <code>/home/user.
322 </code>Then:</p>
323 <ul><li>Create a subdirectory, let's call it <code>myxml</code></li>
324 <li>unpack the libxml2 distribution into that subdirectory</li>
325 <li>chdir into the unpacked distribution (<code>/home/user/myxml/libxml2
326 </code>)</li>
327 <li>configure the library using the "<code>--prefix</code>" switch,
328 specifying an installation subdirectory in <code>/home/user/myxml</code>,
329 e.g.
330 <p><code>./configure --prefix /home/user/myxml/xmlinst</code> {other
331 configuration options}</p></li>
332 <li>now run <code>make</code> followed by <code>make install</code></li>
333 <li>At this point, the installation subdirectory contains the complete
334 "private" include files, library files and binary program files (e.g.
335 xmllint), located in
336 <p> <code>/home/user/myxml/xmlinst/lib, /home/user/myxml/xmlinst/include
337 </code> and <code> /home/user/myxml/xmlinst/bin</code></p>
338 respectively.</li>
339 <li>In order to use this "private" library, you should first add it
340 to the beginning of your default PATH (so that your own private
341 program files such as xmllint will be used instead of the normal
342 system ones). To do this, the Bash command would be
343 <p><code>export PATH=/home/user/myxml/xmlinst/bin:$PATH</code></p></li>
344 <li>Now suppose you have a program <code>test1.c</code> that you would
345 like to compile with your "private" library. Simply compile it
346 using the command <p><code>gcc `xml2-config --cflags --libs` -o test
347 test.c</code></p> Note that, because your PATH has been set with <code>
348 /home/user/myxml/xmlinst/bin</code> at the beginning, the
349 xml2-config program which you just installed will be used instead of
350 the system default one, and this will <em>automatically</em> get the
351 correct libraries linked with your program.</li></ul>
352 </li><p/>
Daniel Veillard0b28e882002-07-24 23:47:05 +0000353 <li><em>xmlDocDump() generates output on one line.</em>
Daniel Veillard8a469172003-06-12 16:05:07 +0000354 <p>Libxml2 will not <strong>invent</strong> spaces in the content of a
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000355 document since <strong>all spaces in the content of a document are
356 significant</strong>. If you build a tree from the API and want
357 indentation:</p>
358 <ol>
Daniel Veillard0b28e882002-07-24 23:47:05 +0000359 <li>the correct way is to generate those yourself too.</li>
Daniel Veillard8a469172003-06-12 16:05:07 +0000360 <li>the dangerous way is to ask libxml2 to add those blanks to your
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000361 content <strong>modifying the content of your document in the
362 process</strong>. The result may not be what you expect. There is
363 <strong>NO</strong> way to guarantee that such a modification won't
Daniel Veillard0b28e882002-07-24 23:47:05 +0000364 affect other parts of the content of your document. See <a
Daniel Veillard5373ea12003-07-24 13:09:13 +0000365 href="http://xmlsoft.org/html/libxml-parser.html#xmlKeepBlanksDefault">xmlKeepBlanksDefault
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000366 ()</a> and <a
Daniel Veillard5373ea12003-07-24 13:09:13 +0000367 href="http://xmlsoft.org/html/libxml-tree.html#xmlSaveFormatFile">xmlSaveFormatFile
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000368 ()</a></li>
369 </ol>
370 </li>
371 <li>Extra nodes in the document:
372 <p><em>For a XML file as below:</em></p>
373 <pre>&lt;?xml version="1.0"?&gt;
374&lt;PLAN xmlns="http://www.argus.ca/autotest/1.0/"&gt;
375&lt;NODE CommFlag="0"/&gt;
376&lt;NODE CommFlag="1"/&gt;
377&lt;/PLAN&gt;</pre>
378 <p><em>after parsing it with the function
379 pxmlDoc=xmlParseFile(...);</em></p>
380 <p><em>I want to the get the content of the first node (node with the
381 CommFlag="0")</em></p>
382 <p><em>so I did it as following;</em></p>
Daniel Veillard63d83142002-05-20 06:51:05 +0000383 <pre>xmlNodePtr pnode;
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000384pnode=pxmlDoc-&gt;children-&gt;children;</pre>
385 <p><em>but it does not work. If I change it to</em></p>
386 <pre>pnode=pxmlDoc-&gt;children-&gt;children-&gt;next;</pre>
387 <p><em>then it works. Can someone explain it to me.</em></p>
388 <p></p>
389 <p>In XML all characters in the content of the document are significant
390 <strong>including blanks and formatting line breaks</strong>.</p>
391 <p>The extra nodes you are wondering about are just that, text nodes with
Daniel Veillard63d83142002-05-20 06:51:05 +0000392 the formatting spaces which are part of the document but that people tend
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000393 to forget. There is a function <a
394 href="http://xmlsoft.org/html/libxml-parser.html">xmlKeepBlanksDefault
395 ()</a> to remove those at parse time, but that's an heuristic, and its
Daniel Veillard0b28e882002-07-24 23:47:05 +0000396 use should be limited to cases where you are certain there is no
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000397 mixed-content in the document.</p>
398 </li>
399 <li><em>I get compilation errors of existing code like when accessing
Daniel Veillard0b28e882002-07-24 23:47:05 +0000400 <strong>root</strong> or <strong>child fields</strong> of nodes.</em>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000401 <p>You are compiling code developed for libxml version 1 and using a
402 libxml2 development environment. Either switch back to libxml v1 devel or
403 even better fix the code to compile with libxml2 (or both) by <a
404 href="upgrade.html">following the instructions</a>.</p>
405 </li>
406 <li><em>I get compilation errors about non existing
407 <strong>xmlRootNode</strong> or <strong>xmlChildrenNode</strong>
Daniel Veillard0b28e882002-07-24 23:47:05 +0000408 fields.</em>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000409 <p>The source code you are using has been <a
410 href="upgrade.html">upgraded</a> to be able to compile with both libxml
411 and libxml2, but you need to install a more recent version:
412 libxml(-devel) &gt;= 1.8.8 or libxml2(-devel) &gt;= 2.1.0</p>
413 </li>
414 <li><em>XPath implementation looks seriously broken</em>
Daniel Veillard0b28e882002-07-24 23:47:05 +0000415 <p>XPath implementation prior to 2.3.0 was really incomplete. Upgrade to
416 a recent version, there are no known bugs in the current version.</p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000417 </li>
Daniel Veillard0b28e882002-07-24 23:47:05 +0000418 <li><em>The example provided in the web page does not compile.</em>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000419 <p>It's hard to maintain the documentation in sync with the code
420 &lt;grin/&gt; ...</p>
Daniel Veillard0b28e882002-07-24 23:47:05 +0000421 <p>Check the previous points 1/ and 2/ raised before, and please send
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000422 patches.</p>
423 </li>
Daniel Veillard8d7b5c72003-11-15 18:24:36 +0000424 <li><em>Where can I get more examples and information than provided on the
Daniel Veillard42766c02002-08-22 20:52:17 +0000425 web page?</em>
Daniel Veillard8a469172003-06-12 16:05:07 +0000426 <p>Ideally a libxml2 book would be nice. I have no such plan ... But you
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000427 can:</p>
428 <ul>
429 <li>check more deeply the <a href="html/libxml-lib.html">existing
430 generated doc</a></li>
Daniel Veillardc480c4e2003-12-10 13:24:38 +0000431 <li>have a look at <a href="examples/index.html">the set of
432 examples</a>.</li>
Daniel Veillard8a469172003-06-12 16:05:07 +0000433 <li>look for examples of use for libxml2 function using the Gnome code.
Daniel Veillard0b28e882002-07-24 23:47:05 +0000434 For example the following will query the full Gnome CVS base for the
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000435 use of the <strong>xmlAddChild()</strong> function:
436 <p><a
437 href="http://cvs.gnome.org/lxr/search?string=xmlAddChild">http://cvs.gnome.org/lxr/search?string=xmlAddChild</a></p>
438 <p>This may be slow, a large hardware donation to the gnome project
439 could cure this :-)</p>
440 </li>
441 <li><a
Daniel Veillardc480c4e2003-12-10 13:24:38 +0000442 href="http://cvs.gnome.org/bonsai/rview.cgi?cvsroot=/cvs/gnome&amp;dir=gnome-xml">Browse
443 the libxml2 source</a> , I try to write code as clean and documented
Daniel Veillard42766c02002-08-22 20:52:17 +0000444 as possible, so looking at it may be helpful. In particular the code
445 of xmllint.c and of the various testXXX.c test programs should
446 provide good examples of how to do things with the library.</li>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000447 </ul>
448 </li>
449 <li>What about C++ ?
Daniel Veillard8a469172003-06-12 16:05:07 +0000450 <p>libxml2 is written in pure C in order to allow easy reuse on a number
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000451 of platforms, including embedded systems. I don't intend to convert to
452 C++.</p>
Daniel Veillard91e69c52003-08-04 01:43:07 +0000453 <p>There is however a C++ wrapper which may fulfill your needs:</p>
Daniel Veillard9b6fd302002-05-13 12:06:47 +0000454 <ul>
455 <li>by Ari Johnson &lt;ari@btigate.com&gt;:
456 <p>Website: <a
Daniel Veillard91e69c52003-08-04 01:43:07 +0000457 href="http://libxmlplusplus.sourceforge.net/">http://libxmlplusplus.sourceforge.net/</a></p>
Daniel Veillard9b6fd302002-05-13 12:06:47 +0000458 <p>Download: <a
Daniel Veillard91e69c52003-08-04 01:43:07 +0000459 href="http://sourceforge.net/project/showfiles.php?group_id=12999">http://sourceforge.net/project/showfiles.php?group_id=12999</a></p>
Daniel Veillard9b6fd302002-05-13 12:06:47 +0000460 </li>
Daniel Veillard83ee40d2003-08-09 22:24:09 +0000461 <!-- Website is currently unavailable as of 2003-08-02
Daniel Veillard9b6fd302002-05-13 12:06:47 +0000462 <li>by Peter Jones &lt;pjones@pmade.org&gt;
Daniel Veillard83ee40d2003-08-09 22:24:09 +0000463 <p>Website: <a
464 href="http://pmade.org/pjones/software/xmlwrapp/">http://pmade.org/pjones/software/xmlwrapp/</a></p>
Daniel Veillard9b6fd302002-05-13 12:06:47 +0000465 </li>
Daniel Veillard83ee40d2003-08-09 22:24:09 +0000466 -->
Daniel Veillard9b6fd302002-05-13 12:06:47 +0000467 </ul>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000468 </li>
469 <li>How to validate a document a posteriori ?
470 <p>It is possible to validate documents which had not been validated at
Daniel Veillard42766c02002-08-22 20:52:17 +0000471 initial parsing time or documents which have been built from scratch
472 using the API. Use the <a
Daniel Veillard5373ea12003-07-24 13:09:13 +0000473 href="http://xmlsoft.org/html/libxml-valid.html#xmlValidateDtd">xmlValidateDtd()</a>
Daniel Veillard63d83142002-05-20 06:51:05 +0000474 function. It is also possible to simply add a DTD to an existing
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000475 document:</p>
476 <pre>xmlDocPtr doc; /* your existing document */
Daniel Veillard0b28e882002-07-24 23:47:05 +0000477xmlDtdPtr dtd = xmlParseDTD(NULL, filename_of_dtd); /* parse the DTD */
478
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000479 dtd-&gt;name = xmlStrDup((xmlChar*)"root_name"); /* use the given root */
480
481 doc-&gt;intSubset = dtd;
482 if (doc-&gt;children == NULL) xmlAddChild((xmlNodePtr)doc, (xmlNodePtr)dtd);
483 else xmlAddPrevSibling(doc-&gt;children, (xmlNodePtr)dtd);
484 </pre>
485 </li>
Daniel Veillarddad3f682002-11-17 16:47:27 +0000486 <li>So what is this funky "xmlChar" used all the time?
487 <p>It is a null terminated sequence of utf-8 characters. And only utf-8!
488 You need to convert strings encoded in different ways to utf-8 before
489 passing them to the API. This can be accomplished with the iconv library
490 for instance.</p>
John Fleck61f6fb62002-10-31 15:23:29 +0000491 </li>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000492 <li>etc ...</li>
493</ol>
494
495<p></p>
496
Daniel Veillard66f68e72003-08-18 16:39:51 +0000497<h2><a name="Documentat">Developer Menu</a></h2>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000498
Daniel Veillard0b28e882002-07-24 23:47:05 +0000499<p>There are several on-line resources related to using libxml:</p>
Daniel Veillard0142b842000-01-14 14:45:24 +0000500<ol>
MST 2003 John Fleck2b7142a2003-11-22 03:55:27 +0000501 <li>Use the <a href="search.php">search engine</a> to look up
502 information.</li>
Daniel Veillard0b28e882002-07-24 23:47:05 +0000503 <li>Check the <a href="FAQ.html">FAQ.</a></li>
Daniel Veillardc19fccc2000-07-03 11:52:01 +0000504 <li>Check the <a href="http://xmlsoft.org/html/libxml-lib.html">extensive
MST 2003 John Fleck2b7142a2003-11-22 03:55:27 +0000505 documentation</a> automatically extracted from code comments.</li>
Daniel Veillard8d869642000-07-14 12:12:59 +0000506 <li>Look at the documentation about <a href="encoding.html">libxml
Daniel Veillard0b28e882002-07-24 23:47:05 +0000507 internationalization support</a>.</li>
Daniel Veillardbc66f852002-01-14 09:49:20 +0000508 <li>This page provides a global overview and <a href="example.html">some
Daniel Veillard402e8c82000-02-29 22:57:47 +0000509 examples</a> on how to use libxml.</li>
Daniel Veillardc480c4e2003-12-10 13:24:38 +0000510 <li><a href="examples/index.html">Code examples</a></li>
Daniel Veillard560c2a42003-07-06 21:13:49 +0000511 <li>John Fleck's libxml2 tutorial: <a href="tutorial/index.html">html</a>
512 or <a href="tutorial/xmltutorial.pdf">pdf</a>.</li>
Daniel Veillard1177ca42003-04-26 22:29:54 +0000513 <li>If you need to parse large files, check the <a
514 href="xmlreader.html">xmlReader</a> API tutorial</li>
Daniel Veillardaf43f632002-03-08 15:05:20 +0000515 <li><a href="mailto:james@daa.com.au">James Henstridge</a> wrote <a
Daniel Veillard402e8c82000-02-29 22:57:47 +0000516 href="http://www.daa.com.au/~james/gnome/xml-sax/xml-sax.html">some nice
517 documentation</a> explaining how to use the libxml SAX interface.</li>
Daniel Veillardc480c4e2003-12-10 13:24:38 +0000518 <li>George Lebl wrote <a
MST 2003 John Fleck2b7142a2003-11-22 03:55:27 +0000519 href="http://www-106.ibm.com/developerworks/library/l-gnome3/">an article
Daniel Veillard402e8c82000-02-29 22:57:47 +0000520 for IBM developerWorks</a> about using libxml.</li>
Daniel Veillardec303412000-03-24 13:41:54 +0000521 <li>Check <a href="http://cvs.gnome.org/lxr/source/gnome-xml/TODO">the TODO
Daniel Veillard0b28e882002-07-24 23:47:05 +0000522 file</a>.</li>
Daniel Veillard42766c02002-08-22 20:52:17 +0000523 <li>Read the <a href="upgrade.html">1.x to 2.x upgrade path</a>
524 description. If you are starting a new project using libxml you should
525 really use the 2.x version.</li>
Daniel Veillard845cce42002-01-09 11:51:37 +0000526 <li>And don't forget to look at the <a
527 href="http://mail.gnome.org/archives/xml/">mailing-list archive</a>.</li>
Daniel Veillard0142b842000-01-14 14:45:24 +0000528</ol>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000529
Daniel Veillardd5f97f82000-09-17 16:38:14 +0000530<h2><a name="Reporting">Reporting bugs and getting help</a></h2>
Daniel Veillard4c3a2031999-11-19 17:46:26 +0000531
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000532<p>Well, bugs or missing features are always possible, and I will make a
533point of fixing them in a timely fashion. The best way to report a bug is to
Daniel Veillardccf996f2003-08-14 10:48:38 +0000534use the <a href="http://bugzilla.gnome.org/buglist.cgi?product=libxml2">Gnome
Daniel Veillard42766c02002-08-22 20:52:17 +0000535bug tracking database</a> (make sure to use the "libxml2" module name). I
536look at reports there regularly and it's good to have a reminder when a bug
537is still open. Be sure to specify that the bug is for the package libxml2.</p>
Daniel Veillard4c3a2031999-11-19 17:46:26 +0000538
Daniel Veillard4ac494b2003-09-18 15:08:00 +0000539<p>For small problems you can try to get help on IRC, the #xml channel on
540irc.gnome.org (port 6667) usually have a few person subscribed which may help
541(but there is no garantee and if a real issue is raised it should go on the
542mailing-list for archival).</p>
Daniel Veillard9582d6c2003-09-16 11:40:04 +0000543
Daniel Veillard0142b842000-01-14 14:45:24 +0000544<p>There is also a mailing-list <a
Daniel Veillard3197f162001-04-04 00:40:08 +0000545href="mailto:xml@gnome.org">xml@gnome.org</a> for libxml, with an <a
546href="http://mail.gnome.org/archives/xml/">on-line archive</a> (<a
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000547href="http://xmlsoft.org/messages">old</a>). To subscribe to this list,
548please visit the <a
549href="http://mail.gnome.org/mailman/listinfo/xml">associated Web</a> page and
550follow the instructions. <strong>Do not send code, I won't debug it</strong>
551(but patches are really appreciated!).</p>
Daniel Veillardd99224d2004-04-06 10:04:16 +0000552
553<p>Please note that with the current amount of virus and SPAM, sending mail
554to the list without being subscribed won't work. There is *far too many
555bounces* (in the order of a thousand a day !) I cannot approve them manually
556anymore. If your mail to the list bounced waiting for administrator approval,
557it is LOST ! Repost it and fix the problem triggering the error.</p>
Daniel Veillard234547b2001-07-05 09:46:10 +0000558
Daniel Veillard008186f2001-09-13 14:24:44 +0000559<p>Check the following <strong><span style="color: #FF0000">before
560posting</span></strong>:</p>
Daniel Veillard234547b2001-07-05 09:46:10 +0000561<ul>
Daniel Veillard321be0c2002-10-08 21:26:42 +0000562 <li>Read the <a href="FAQ.html">FAQ</a> and <a href="search.php">use the
Daniel Veillarda37aab82003-06-09 09:10:36 +0000563 search engine</a> to get information related to your problem.</li>
Daniel Veillard0b28e882002-07-24 23:47:05 +0000564 <li>Make sure you are <a href="ftp://xmlsoft.org/">using a recent
565 version</a>, and that the problem still shows up in a recent version.</li>
566 <li>Check the <a href="http://mail.gnome.org/archives/xml/">list
567 archives</a> to see if the problem was reported already. In this case
Daniel Veillard63d83142002-05-20 06:51:05 +0000568 there is probably a fix available, similarly check the <a
Daniel Veillardccf996f2003-08-14 10:48:38 +0000569 href="http://bugzilla.gnome.org/buglist.cgi?product=libxml2">registered
Daniel Veillard0b28e882002-07-24 23:47:05 +0000570 open bugs</a>.</li>
571 <li>Make sure you can reproduce the bug with xmllint or one of the test
572 programs found in source in the distribution.</li>
Daniel Veillard234547b2001-07-05 09:46:10 +0000573 <li>Please send the command showing the error as well as the input (as an
Daniel Veillard63d83142002-05-20 06:51:05 +0000574 attachment)</li>
Daniel Veillard234547b2001-07-05 09:46:10 +0000575</ul>
Daniel Veillard0142b842000-01-14 14:45:24 +0000576
Daniel Veillarda37aab82003-06-09 09:10:36 +0000577<p>Then send the bug with associated information to reproduce it to the <a
Daniel Veillard33a67802001-03-07 09:44:02 +0000578href="mailto:xml@gnome.org">xml@gnome.org</a> list; if it's really libxml
Daniel Veillard98d071d2003-01-10 09:22:44 +0000579related I will approve it. Please do not send mail to me directly, it makes
Daniel Veillard0b28e882002-07-24 23:47:05 +0000580things really hard to track and in some cases I am not the best person to
Daniel Veillard98d071d2003-01-10 09:22:44 +0000581answer a given question, ask on the list.</p>
582
583<p>To <span style="color: #E50000">be really clear about support</span>:</p>
584<ul>
Daniel Veillarda37aab82003-06-09 09:10:36 +0000585 <li>Support or help <span style="color: #E50000">requests MUST be sent to
Daniel Veillard98d071d2003-01-10 09:22:44 +0000586 the list or on bugzilla</span> in case of problems, so that the Question
587 and Answers can be shared publicly. Failing to do so carries the implicit
588 message "I want free support but I don't want to share the benefits with
Daniel Veillard831e8fd2003-01-25 11:45:34 +0000589 others" and is not welcome. I will automatically Carbon-Copy the
590 xml@gnome.org mailing list for any technical reply made about libxml2 or
591 libxslt.</li>
Daniel Veillard560c2a42003-07-06 21:13:49 +0000592 <li>There is <span style="color: #E50000">no garantee of support</span>, if
593 your question remains unanswered after a week, repost it, making sure you
594 gave all the detail needed and the information requested.</li>
Daniel Veillarda37aab82003-06-09 09:10:36 +0000595 <li>Failing to provide information as requested or double checking first
Daniel Veillard98d071d2003-01-10 09:22:44 +0000596 for prior feedback also carries the implicit message "the time of the
597 library maintainers is less valuable than my time" and might not be
598 welcome.</li>
599</ul>
Daniel Veillard4c3a2031999-11-19 17:46:26 +0000600
Daniel Veillard91e9d582001-02-26 07:31:12 +0000601<p>Of course, bugs reported with a suggested patch for fixing them will
Daniel Veillard0b28e882002-07-24 23:47:05 +0000602probably be processed faster than those without.</p>
Daniel Veillardec303412000-03-24 13:41:54 +0000603
604<p>If you're looking for help, a quick look at <a
Daniel Veillardf7ed3362001-08-17 12:01:21 +0000605href="http://mail.gnome.org/archives/xml/">the list archive</a> may actually
Daniel Veillard560c2a42003-07-06 21:13:49 +0000606provide the answer. I usually send source samples when answering libxml2
607usage questions. The <a
608href="http://xmlsoft.org/html/book1.html">auto-generated documentation</a> is
609not as polished as I would like (i need to learn more about DocBook), but
610it's a good starting point.</p>
Daniel Veillardec303412000-03-24 13:41:54 +0000611
Daniel Veillardd5f97f82000-09-17 16:38:14 +0000612<h2><a name="help">How to help</a></h2>
613
614<p>You can help the project in various ways, the best thing to do first is to
615subscribe to the mailing-list as explained before, check the <a
Daniel Veillardf7ed3362001-08-17 12:01:21 +0000616href="http://mail.gnome.org/archives/xml/">archives </a>and the <a
Daniel Veillardccf996f2003-08-14 10:48:38 +0000617href="http://bugzilla.gnome.org/buglist.cgi?product=libxml2">Gnome bug
Daniel Veillard0b28e882002-07-24 23:47:05 +0000618database</a>:</p>
Daniel Veillardd5f97f82000-09-17 16:38:14 +0000619<ol>
Daniel Veillard0b28e882002-07-24 23:47:05 +0000620 <li>Provide patches when you find problems.</li>
Daniel Veillard8a469172003-06-12 16:05:07 +0000621 <li>Provide the diffs when you port libxml2 to a new platform. They may not
Daniel Veillardab8500d2000-10-15 21:06:19 +0000622 be integrated in all cases but help pinpointing portability problems
623 and</li>
Daniel Veillard0b28e882002-07-24 23:47:05 +0000624 <li>Provide documentation fixes (either as patches to the code comments or
Daniel Veillardd5f97f82000-09-17 16:38:14 +0000625 as HTML diffs).</li>
Daniel Veillard42766c02002-08-22 20:52:17 +0000626 <li>Provide new documentations pieces (translations, examples, etc
627 ...).</li>
Daniel Veillard0b28e882002-07-24 23:47:05 +0000628 <li>Check the TODO file and try to close one of the items.</li>
629 <li>Take one of the points raised in the archive or the bug database and
Daniel Veillarde7ead2d2001-08-22 23:44:09 +0000630 provide a fix. <a href="mailto:daniel@veillard.com">Get in touch with me
631 </a>before to avoid synchronization problems and check that the suggested
632 fix will fit in nicely :-)</li>
Daniel Veillardd5f97f82000-09-17 16:38:14 +0000633</ol>
634
Daniel Veillard10a2c651999-12-12 13:03:50 +0000635<h2><a name="Downloads">Downloads</a></h2>
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000636
Daniel Veillard688f6692004-03-26 10:57:38 +0000637<p>The latest versions of libxml2 can be found on the <a
Daniel Veillardeca726d2004-04-18 21:47:34 +0000638href="ftp://xmlsoft.org/">xmlsoft.org</a> server ( <a
639href="http://xmlsoft.org/sources/">HTTP</a>, <a
640href="ftp://xmlsoft.org/">FTP</a> and rsync are available), there is also
Daniel Veillard210818b2004-09-29 15:50:37 +0000641mirrors (<a href="ftp://ftp.planetmirror.com/pub/xmlsoft/">Australia</a>( <a
642href="http://xmlsoft.planetmirror.com/">Web</a>), <a
Daniel Veillard20c8cf22001-06-26 22:47:36 +0000643href="ftp://fr.rpmfind.net/pub/libxml/">France</a>) or on the <a
Daniel Veillardd99224d2004-04-06 10:04:16 +0000644href="ftp://ftp.gnome.org/pub/GNOME/MIRRORS.html">Gnome FTP server</a> as <a
645href="ftp://ftp.gnome.org/pub/GNOME/sources/libxml2/2.6/">source archive</a>
Daniel Veillard688f6692004-03-26 10:57:38 +0000646, Antonin Sprinzl also provide <a href="ftp://gd.tuwien.ac.at/pub/libxml/">a
Daniel Veillarde16b5742002-09-26 17:50:03 +0000647mirror in Austria</a>. (NOTE that you need both the <a
Daniel Veillardc19fccc2000-07-03 11:52:01 +0000648href="http://rpmfind.net/linux/RPM/libxml2.html">libxml(2)</a> and <a
649href="http://rpmfind.net/linux/RPM/libxml2-devel.html">libxml(2)-devel</a>
Daniel Veillardb46a5732003-04-08 13:35:48 +0000650packages installed to compile applications using libxml.)</p>
Daniel Veillardeca726d2004-04-18 21:47:34 +0000651
652<p>You can find all the history of libxml(2) and libxslt releases in the <a
Daniel Veillardd4cfcef2004-05-06 18:55:27 +0000653href="http://xmlsoft.org/sources/old/">old</a> directory. The precompiled
Daniel Veillardf81a8e82004-08-03 21:58:41 +0000654Windows binaries made by Igor Zlatovic are available in the <a
655href="http://xmlsoft.org/sources/win32/">win32</a> directory.</p>
Daniel Veillardb46a5732003-04-08 13:35:48 +0000656
657<p>Binary ports:</p>
658<ul>
659 <li>Red Hat RPMs for i386 are available directly on <a
660 href="ftp://xmlsoft.org/">xmlsoft.org</a>, the source RPM will compile on
661 any architecture supported by Red Hat.</li>
Daniel Veillardb331fff2004-08-22 14:21:57 +0000662 <li><a href="mailto:igor@zlatkovic.com">Igor Zlatkovic</a> is now the
663 maintainer of the Windows port, <a
Daniel Veillardb46a5732003-04-08 13:35:48 +0000664 href="http://www.zlatkovic.com/projects/libxml/index.html">he provides
Daniel Veillardb11f5b92004-08-03 22:09:36 +0000665 binaries</a>.</li>
MST 2004 John Fleckb759b302004-12-21 15:14:08 +0000666 <li>Blastwave provides
667 <a href="http://www.blastwave.org/packages.php/libxml2">Solaris binaries</a>.</li>
Daniel Veillardb46a5732003-04-08 13:35:48 +0000668 <li><a href="mailto:Steve.Ball@zveno.com">Steve Ball</a> provides <a
669 href="http://www.zveno.com/open_source/libxml2xslt.html">Mac Os X
670 binaries</a>.</li>
671 <li>The HP-UX porting center provides <a
672 href="http://hpux.connect.org.uk/hppd/hpux/Gnome/">HP-UX binaries</a></li>
673</ul>
674
675<p>If you know other supported binary ports, please <a
676href="http://veillard.com/">contact me</a>.</p>
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000677
Daniel Veillard6c8b1172000-03-01 00:40:41 +0000678<p><a name="Snapshot">Snapshot:</a></p>
679<ul>
Daniel Veillard3cef1192004-08-18 09:30:31 +0000680 <li>Code from the W3C cvs base libxml2 module, updated hourly <a
Daniel Veillardfc263f12004-08-31 07:02:04 +0000681 href="ftp://xmlsoft.org/libxml2-cvs-snapshot.tar.gz">libxml2-cvs-snapshot.tar.gz</a>.</li>
Daniel Veillard6c8b1172000-03-01 00:40:41 +0000682 <li>Docs, content of the web site, the list archive included <a
Daniel Veillard0b28e882002-07-24 23:47:05 +0000683 href="ftp://xmlsoft.org/libxml-docs.tar.gz">libxml-docs.tar.gz</a>.</li>
Daniel Veillard6c8b1172000-03-01 00:40:41 +0000684</ul>
685
Daniel Veillardc6271d22001-10-27 07:50:58 +0000686<p><a name="Contribs">Contributions:</a></p>
Daniel Veillard6c8b1172000-03-01 00:40:41 +0000687
688<p>I do accept external contributions, especially if compiling on another
Daniel Veillardd99224d2004-04-06 10:04:16 +0000689platform, get in touch with the list to upload the package, wrappers for
690various languages have been provided, and can be found in the <a
691href="python.html">bindings section</a></p>
Daniel Veillard6c8b1172000-03-01 00:40:41 +0000692
Daniel Veillard8a469172003-06-12 16:05:07 +0000693<p>Libxml2 is also available from CVS:</p>
Daniel Veillard10a2c651999-12-12 13:03:50 +0000694<ul>
Daniel Veillardb331fff2004-08-22 14:21:57 +0000695 <li><p>The <a href="http://cvs.gnome.org/viewcvs/libxml2/">Gnome CVS
696 base</a>. Check the <a
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000697 href="http://developer.gnome.org/tools/cvs.html">Gnome CVS Tools</a>
Daniel Veillardd99224d2004-04-06 10:04:16 +0000698 page; the CVS module is <b>libxml2</b>.</p>
Daniel Veillard10a2c651999-12-12 13:03:50 +0000699 </li>
Daniel Veillard82687162001-01-22 15:32:01 +0000700 <li>The <strong>libxslt</strong> module is also present there</li>
Daniel Veillard10a2c651999-12-12 13:03:50 +0000701</ul>
702
Daniel Veillard78fed532004-10-09 19:44:48 +0000703<h2><a name="News">Releases</a></h2>
Daniel Veillard10a2c651999-12-12 13:03:50 +0000704
Daniel Veillarde6d8e202002-05-02 06:11:10 +0000705<p>Items not finished and worked on, get in touch with the list if you want
Daniel Veillard688f6692004-03-26 10:57:38 +0000706to help those</p>
Daniel Veillardab8500d2000-10-15 21:06:19 +0000707<ul>
Daniel Veillard72fef162003-02-05 14:31:19 +0000708 <li>More testing on RelaxNG</li>
Daniel Veillardcf27f7c2002-04-30 07:12:39 +0000709 <li>Finishing up <a href="http://www.w3.org/TR/xmlschema-1/">XML
Daniel Veillard72fef162003-02-05 14:31:19 +0000710 Schemas</a></li>
711</ul>
712
Daniel Veillard2d908032004-08-10 10:16:36 +0000713<p>The <a href="ChangeLog.html">change log</a> describes the recents commits
714to the <a href="http://cvs.gnome.org/viewcvs/libxml2/">CVS</a> code base.</p>
715
Daniel Veillardd99224d2004-04-06 10:04:16 +0000716<p>There is the list of public releases:</p>
717
Daniel Veillard57c000e2005-03-13 18:34:29 +0000718<h3>2.6.18: Mar 13 2005</h3>
719<ul>
720 <li> build fixes: warnings (Peter Breitenlohner), testapi.c generation,
721 Bakefile support (Francesco Montorsi), Windows compilation (Joel Reed),
722 some gcc4 fixes, HP-UX portability fixes (Rick Jones).</li>
723 <li> bug fixes: xmlSchemaElementDump namespace (Kasimier Buchcik), push and
724 xmlreader stopping on non-fatal errors, thread support for dictionnaries
725 reference counting (Gary Coady), internal subset and push problem,
726 URL saved in xmlCopyDoc, various schemas bug fixes (Kasimier), Python
727 paths fixup (Stephane Bidoul), xmlGetNodePath and namespaces,
728 xmlSetNsProp fix (Mike Hommey), warning should not count as error
729 (William Brack), xmlCreatePushParser empty chunk, XInclude parser
730 flags (William), cleanup FTP and HTTP code to reuse the uri parsing
731 and IPv6 (William), xmlTextWriterStartAttributeNS fix (Rob Richards),
732 XMLLINT_INDENT being empty (William), xmlWriter bugs (Rob Richards),
733 multithreading on Windows (Rich Salz), xmlSearchNsByHref fix (Kasimier),
734 Python binding leak (Brent Hendricks), aliasing bug exposed by gcc4
735 on s390, xmlTextReaderNext bug (Rob Richards), Schemas decimal type
736 fixes (William Brack), xmlByteConsumed static buffer (Ben Maurer).</li>
737 <li> improvement: speedup parsing comments and DTDs, dictionnary support for
738 hash tables, Schemas Identity constraints (Kasimier), streaming XPath
739 subset, xmlTextReaderReadString added (Bjorn Reese), Schemas canonical
740 values handling (Kasimier), add xmlTextReaderByteConsumed (Aron
741 Stansvik), </li>
742 <li> Documentation: Wiki support (Joel Reed)
743</ul>
Daniel Veillard298d9642005-01-16 20:01:55 +0000744<h3>2.6.17: Jan 16 2005</h3>
745<ul>
746 <li>build fixes: Windows, warnings removal (William Brack),
747 maintainer-clean dependency(William), build in a different directory
748 (William), fixing --with-minimum configure build (William), BeOS
749 build (Marcin Konicki), Python-2.4 detection (William), compilation
750 on AIX (Dan McNichol)</li>
751 <li>bug fixes: xmlTextReaderHasAttributes (Rob Richards), xmlCtxtReadFile()
752 to use the catalog(s), loop on output (William Brack), XPath memory leak,
753 ID deallocation problem (Steve Shepard), debugDumpNode crash (William),
754 warning not using error callback (William), xmlStopParser bug (William),
755 UTF-16 with BOM on DTDs (William), namespace bug on empty elements
756 in push mode (Rob Richards), line and col computations fixups (Aleksey
757 Sanin), xmlURIEscape fix (William), xmlXPathErr on bad range (William),
758 patterns with too many steps, bug in RNG choice optimization, line
759 number sometimes missing.
760 </li>
761 <li>improvements: XSD Schemas (Kasimier Buchcik), python generator (William),
762 xmlUTF8Strpos speedup (William), unicode Python strings (William),
763 XSD error reports (Kasimier Buchcik), Python __str__ call serialize().
764 </li>
765 <li>new APIs: added xmlDictExists(), GetLineNumber and GetColumnNumber
766 for the xmlReader (Aleksey Sanin), Dynamic Shared Libraries APIs
767 (mostly Joel Reed), error extraction API from regexps, new XMLSave
768 option for format (Phil Shafer)</li>
769 <li>documentation: site improvement (John Fleck), FAQ entries (William).</li>
770</ul>
771
Daniel Veillardc3d7cb42004-11-10 14:34:45 +0000772<h3>2.6.16: Nov 10 2004</h3>
773<ul>
774 <li>general hardening and bug fixing crossing all the API based on new
775 automated regression testing</li>
776 <li>build fix: IPv6 build and test on AIX (Dodji Seketeli)</li>
777 <li>bug fixes: problem with XML::Libxml reported by Petr Pajas, encoding
778 conversion functions return values, UTF-8 bug affecting XPath reported by
779 Markus Bertheau, catalog problem with NULL entries (William Brack)</li>
780 <li>documentation: fix to xmllint man page, some API function descritpion
781 were updated.</li>
782 <li>improvements: DTD validation APIs provided at the Python level (Brent
783 Hendricks) </li>
784</ul>
785
Daniel Veillardc2f83d12004-10-27 22:59:21 +0000786<h3>2.6.15: Oct 27 2004</h3>
Daniel Veillard6927b102004-10-27 17:29:04 +0000787<ul>
788 <li>security fixes on the nanoftp and nanohttp modules</li>
789 <li>build fixes: xmllint detection bug in configure, building outside the
790 source tree (Thomas Fitzsimmons)</li>
791 <li>bug fixes: HTML parser on broken ASCII chars in names (William), Python
792 paths (Malcolm Tredinnick), xmlHasNsProp and default namespace (William),
793 saving to python file objects (Malcolm Tredinnick), DTD lookup fix
794 (Malcolm), save back &lt;group&gt; in catalogs (William), tree build
795 fixes (DV and Rob Richards), Schemas memory bug, structured error handler
796 on Python 64bits, thread local memory deallocation, memory leak reported
797 by Volker Roth, xmlValidateDtd in the presence of an internal subset,
798 entities and _private problem (William), xmlBuildRelativeURI error
799 (William).</li>
800 <li>improvements: better XInclude error reports (William), tree debugging
801 module and tests, convenience functions at the Reader API (Graham
802 Bennett), add support for PI in the HTML parser.</li>
803</ul>
804
Daniel Veillard210818b2004-09-29 15:50:37 +0000805<h3>2.6.14: Sep 29 2004</h3>
806<ul>
807 <li>build fixes: configure paths for xmllint and xsltproc, compilation
808 without HTML parser, compilation warning cleanups (William Brack &amp;
Daniel Veillard6927b102004-10-27 17:29:04 +0000809 Malcolm Tredinnick), VMS makefile update (Craig Berry),</li>
Daniel Veillard210818b2004-09-29 15:50:37 +0000810 <li>bug fixes: xmlGetUTF8Char (William Brack), QName properties (Kasimier
811 Buchcik), XInclude testing, Notation serialization, UTF8ToISO8859x
812 transcoding (Mark Itzcovitz), lots of XML Schemas cleanup and fixes
813 (Kasimier), ChangeLog cleanup (Stepan Kasal), memory fixes (Mark Vakoc),
814 handling of failed realloc(), out of bound array adressing in Schemas
815 date handling, Python space/tabs cleanups (Malcolm Tredinnick), NMTOKENS
Daniel Veillard6927b102004-10-27 17:29:04 +0000816 E20 validation fix (Malcolm),</li>
Daniel Veillard210818b2004-09-29 15:50:37 +0000817 <li>improvements: added W3C XML Schemas testsuite (Kasimier Buchcik), add
818 xmlSchemaValidateOneElement (Kasimier), Python exception hierearchy
819 (Malcolm Tredinnick), Python libxml2 driver improvement (Malcolm
820 Tredinnick), Schemas support for xsi:schemaLocation,
821 xsi:noNamespaceSchemaLocation, xsi:type (Kasimier Buchcik)</li>
822</ul>
823
Daniel Veillardd1de4a32004-08-31 13:43:07 +0000824<h3>2.6.13: Aug 31 2004</h3>
825<ul>
826 <li>build fixes: Windows and zlib (Igor Zlatkovic), -O flag with gcc,
Daniel Veillard210818b2004-09-29 15:50:37 +0000827 Solaris compiler warning, fixing RPM BuildRequires,</li>
Daniel Veillardd1de4a32004-08-31 13:43:07 +0000828 <li>fixes: DTD loading on Windows (Igor), Schemas error reports APIs
829 (Kasimier Buchcik), Schemas validation crash, xmlCheckUTF8 (William Brack
830 and Julius Mittenzwei), Schemas facet check (Kasimier), default namespace
831 problem (William), Schemas hexbinary empty values, encoding error could
832 genrate a serialization loop.</li>
833 <li>Improvements: Schemas validity improvements (Kasimier), added --path
834 and --load-trace options to xmllint</li>
835 <li>documentation: tutorial update (John Fleck)</li>
836</ul>
837
Daniel Veillardb331fff2004-08-22 14:21:57 +0000838<h3>2.6.12: Aug 22 2004</h3>
839<ul>
840 <li>build fixes: fix --with-minimum, elfgcchack.h fixes (Peter
841 Breitenlohner), perl path lookup (William), diff on Solaris (Albert
842 Chin), some 64bits cleanups.</li>
843 <li>Python: avoid a warning with 2.3 (William Brack), tab and space mixes
844 (William), wrapper generator fixes (William), Cygwin support (Gerrit P.
845 Haase), node wrapper fix (Marc-Antoine Parent), XML Schemas support
846 (Torkel Lyng)</li>
847 <li>Schemas: a lot of bug fixes and improvements from Kasimier Buchcik</li>
848 <li>fixes: RVT fixes (William), XPath context resets bug (William), memory
849 debug (Steve Hay), catalog white space handling (Peter Breitenlohner),
850 xmlReader state after attribute reading (William), structured error
851 handler (William), XInclude generated xml:base fixup (William), Windows
852 memory reallocation problem (Steve Hay), Out of Memory conditions
853 handling (William and Olivier Andrieu), htmlNewDoc() charset bug,
854 htmlReadMemory init (William), a posteriori validation DTD base
855 (William), notations serialization missing, xmlGetNodePath (Dodji),
856 xmlCheckUTF8 (Diego Tartara), missing line numbers on entity
857 (William)</li>
858 <li>improvements: DocBook catalog build scrip (William), xmlcatalog tool
859 (Albert Chin), xmllint --c14n option, no_proxy environment (Mike Hommey),
860 xmlParseInNodeContext() addition, extend xmllint --shell, allow XInclude
861 to not generate start/end nodes, extend xmllint --version to include CVS
862 tag (William)</li>
863 <li>documentation: web pages fixes, validity API docs fixes (William)
864 schemas API fix (Eric Haszlakiewicz), xmllint man page (John Fleck)</li>
865</ul>
866
Daniel Veillard45cb0f42004-07-05 17:45:35 +0000867<h3>2.6.11: July 5 2004</h3>
868<ul>
869 <li>Schemas: a lot of changes and improvements by Kasimier Buchcik for
870 attributes, namespaces and simple types.</li>
871 <li>build fixes: --with-minimum (William Brack), some gcc cleanup
872 (William), --with-thread-alloc (William)</li>
873 <li>portability: Windows binary package change (Igor Zlatkovic), Catalog
874 path on Windows</li>
875 <li>documentation: update to the tutorial (John Fleck), xmllint return code
Daniel Veillardb331fff2004-08-22 14:21:57 +0000876 (John Fleck), man pages (Ville Skytta),</li>
Daniel Veillard45cb0f42004-07-05 17:45:35 +0000877 <li>bug fixes: C14N bug serializing namespaces (Aleksey Sanin), testSAX
878 properly initialize the library (William), empty node set in XPath
879 (William), xmlSchemas errors (William), invalid charref problem pointed
880 by Morus Walter, XInclude xml:base generation (William), Relax-NG bug
Daniel Veillardb331fff2004-08-22 14:21:57 +0000881 with div processing (William), XPointer and xml:base problem(William),
Daniel Veillard45cb0f42004-07-05 17:45:35 +0000882 Reader and entities, xmllint return code for schemas (William), reader
883 streaming problem (Steve Ball), DTD serialization problem (William),
884 libxml.m4 fixes (Mike Hommey), do not provide destructors as methods on
885 Python classes, xmlReader buffer bug, Python bindings memory interfaces
886 improvement (with Stéphane Bidoul), Fixed the push parser to be back to
887 synchronous behaviour.</li>
888 <li>improvement: custom per-thread I/O enhancement (Rob Richards), register
889 namespace in debug shell (Stefano Debenedetti), Python based regression
890 test for non-Unix users (William), dynamically increase the number of
891 XPath extension functions in Python and fix a memory leak (Marc-Antoine
892 Parent and William)</li>
893 <li>performance: hack done with Arjan van de Ven to reduce ELF footprint
894 and generated code on Linux, plus use gcc runtime profiling to optimize
895 the code generated in the RPM packages.</li>
896</ul>
897
Daniel Veillard81205012004-05-18 03:06:41 +0000898<h3>2.6.10: May 17 2004</h3>
899<ul>
900 <li>Web page generated for ChangeLog</li>
901 <li>build fixes: --without-html problems, make check without make all</li>
902 <li>portability: problem with xpath.c on Windows (MSC and Borland), memcmp
903 vs. strncmp on Solaris, XPath tests on Windows (Mark Vakoc), C++ do not
904 use "list" as parameter name, make tests work with Python 1.5 (Ed
905 Davis),</li>
906 <li>improvements: made xmlTextReaderMode public, small buffers resizing
907 (Morten Welinder), add --maxmem option to xmllint, add
908 xmlPopInputCallback() for Matt Sergeant, refactoring of serialization
Daniel Veillard45cb0f42004-07-05 17:45:35 +0000909 escaping, added escaping customization</li>
Daniel Veillard81205012004-05-18 03:06:41 +0000910 <li>bugfixes: xsd:extension (Taihei Goi), assorted regexp bugs (William
911 Brack), xmlReader end of stream problem, node deregistration with reader,
912 URI escaping and filemanes, XHTML1 formatting (Nick Wellnhofer), regexp
913 transition reduction (William), various XSD Schemas fixes (Kasimier
914 Buchcik), XInclude fallback problem (William), weird problems with DTD
915 (William), structured error handler callback context (William), reverse
916 xmlEncodeSpecialChars() behaviour back to escaping '"'</li>
917</ul>
918
Daniel Veillardeca726d2004-04-18 21:47:34 +0000919<h3>2.6.9: Apr 18 2004</h3>
920<ul>
921 <li>implement xml:id Working Draft, relaxed XPath id() checking</li>
922 <li>bugfixes: xmlCtxtReset (Brent Hendricks), line number and CDATA (Dave
923 Beckett), Relax-NG compilation (William Brack), Regexp patches (with
924 William), xmlUriEscape (Mark Vakoc), a Relax-NG notAllowed problem (with
925 William), Relax-NG name classes compares (William), XInclude duplicate
926 fallback (William), external DTD encoding detection (William), a DTD
927 validation bug (William), xmlReader Close() fix, recusive extention
928 schemas</li>
929 <li>improvements: use xmlRead* APIs in test tools (Mark Vakoc), indenting
930 save optimization, better handle IIS broken HTTP redirect behaviour (Ian
931 Hummel), HTML parser frameset (James Bursa), libxml2-python RPM
932 dependancy, XML Schemas union support (Kasimier Buchcik), warning removal
933 clanup (William), keep ChangeLog compressed when installing from RPMs</li>
934 <li>documentation: examples and xmlDocDumpMemory docs (John Fleck), new
Daniel Veillardd4cfcef2004-05-06 18:55:27 +0000935 example (load, xpath, modify, save), xmlCatalogDump() comments,</li>
Daniel Veillardeca726d2004-04-18 21:47:34 +0000936 <li>Windows: Borland C++ builder (Eric Zurcher), work around Microsoft
937 compiler NaN handling bug (Mark Vakoc)</li>
938</ul>
939
Daniel Veillard252004d2004-03-23 12:32:32 +0000940<h3>2.6.8: Mar 23 2004</h3>
941<ul>
942 <li>First step of the cleanup of the serialization code and APIs</li>
943 <li>XML Schemas: mixed content (Adam Dickmeiss), QName handling fixes (Adam
944 Dickmeiss), anyURI for "" (John Belmonte)</li>
945 <li>Python: Canonicalization C14N support added (Anthony Carrico)</li>
946 <li>xmlDocCopyNode() extension (William)</li>
947 <li>Relax-NG: fix when processing XInclude results (William), external
948 reference in interleave (William), missing error on &lt;choice&gt;
949 failure (William), memory leak in schemas datatype facets.</li>
950 <li>xmlWriter: patch for better DTD support (Alfred Mickautsch)</li>
951 <li>bug fixes: xmlXPathLangFunction memory leak (Mike Hommey and William
952 Brack), no ID errors if using HTML_PARSE_NOERROR, xmlcatalog fallbacks to
953 URI on SYSTEM lookup failure, XInclude parse flags inheritance (William),
954 XInclude and XPointer fixes for entities (William), XML parser bug
955 reported by Holger Rauch, nanohttp fd leak (William), regexps char
956 groups '-' handling (William), dictionnary reference counting problems,
Daniel Veillardd99224d2004-04-06 10:04:16 +0000957 do not close stderr.</li>
Daniel Veillard252004d2004-03-23 12:32:32 +0000958 <li>performance patches from Petr Pajas</li>
959 <li>Documentation fixes: XML_CATALOG_FILES in man pages (Mike Hommey)</li>
960 <li>compilation and portability fixes: --without-valid, catalog cleanups
961 (Peter Breitenlohner), MingW patch (Roland Schwingel), cross-compilation
962 to Windows (Christophe de Vienne), --with-html-dir fixup (Julio Merino
963 Vidal), Windows build (Eric Zurcher)</li>
964</ul>
965
Daniel Veillard92914492004-02-23 16:33:21 +0000966<h3>2.6.7: Feb 23 2004</h3>
967<ul>
968 <li>documentation: tutorial updates (John Fleck), benchmark results</li>
969 <li>xmlWriter: updates and fixes (Alfred Mickautsch, Lucas Brasilino)</li>
970 <li>XPath optimization (Petr Pajas)</li>
971 <li>DTD ID handling optimization</li>
972 <li>bugfixes: xpath number with &gt; 19 fractional (William Brack), push
973 mode with unescaped '&gt;' characters, fix xmllint --stream --timing, fix
974 xmllint --memory --stream memory usage, xmlAttrSerializeTxtContent
975 handling NULL, trying to fix Relax-NG/Perl interface.</li>
976 <li>python: 2.3 compatibility, whitespace fixes (Malcolm Tredinnick)</li>
977 <li>Added relaxng option to xmllint --shell</li>
978</ul>
979
Daniel Veillard5c9547e2004-02-12 15:31:49 +0000980<h3>2.6.6: Feb 12 2004</h3>
981<ul>
982 <li>nanohttp and nanoftp: buffer overflow error on URI parsing (Igor and
983 William) reported by Yuuichi Teranishi</li>
984 <li>bugfixes: make test and path issues, xmlWriter attribute serialization
985 (William Brack), xmlWriter indentation (William), schemas validation
986 (Eric Haszlakiewicz), XInclude dictionnaries issues (William and Oleg
987 Paraschenko), XInclude empty fallback (William), HTML warnings (William),
988 XPointer in XInclude (William), Python namespace serialization,
989 isolat1ToUTF8 bound error (Alfred Mickautsch), output of parameter
990 entities in internal subset (William), internal subset bug in push mode,
991 &lt;xs:all&gt; fix (Alexey Sarytchev)</li>
992 <li>Build: fix for automake-1.8 (Alexander Winston), warnings removal
993 (Philip Ludlam), SOCKLEN_T detection fixes (Daniel Richard), fix
994 --with-minimum configuration.</li>
995 <li>XInclude: allow the 2001 namespace without warning.</li>
996 <li>Documentation: missing example/index.html (John Fleck), version
997 dependancies (John Fleck)</li>
998 <li>reader API: structured error reporting (Steve Ball)</li>
999 <li>Windows compilation: mingw, msys (Mikhail Grushinskiy), function
1000 prototype (Cameron Johnson), MSVC6 compiler warnings, _WINSOCKAPI_
1001 patch</li>
1002 <li>Parsers: added xmlByteConsumed(ctxt) API to get the byte offest in
1003 input.</li>
1004</ul>
1005
Daniel Veillard189f46b2004-01-25 21:03:04 +00001006<h3>2.6.5: Jan 25 2004</h3>
1007<ul>
1008 <li>Bugfixes: dictionnaries for schemas (William Brack), regexp segfault
1009 (William), xs:all problem (William), a number of XPointer bugfixes
1010 (William), xmllint error go to stderr, DTD validation problem with
1011 namespace, memory leak (William), SAX1 cleanup and minimal options fixes
1012 (Mark Vadoc), parser context reset on error (Shaun McCance), XPath union
1013 evaluation problem (William) , xmlReallocLoc with NULL (Aleksey Sanin),
1014 XML Schemas double free (Steve Ball), XInclude with no href, argument
1015 callbacks order for XPath callbacks (Frederic Peters)</li>
1016 <li>Documentation: python scripts (William Brack), xslt stylesheets (John
1017 Fleck), doc (Sven Zimmerman), I/O example.</li>
1018 <li>Python bindings: fixes (William), enum support (Stéphane Bidoul),
1019 structured error reporting (Stéphane Bidoul)</li>
1020 <li>XInclude: various fixes for conformance, problem related to dictionnary
1021 references (William &amp; me), recursion (William)</li>
1022 <li>xmlWriter: indentation (Lucas Brasilino), memory leaks (Alfred
Daniel Veillard5c9547e2004-02-12 15:31:49 +00001023 Mickautsch),</li>
Daniel Veillard189f46b2004-01-25 21:03:04 +00001024 <li>xmlSchemas: normalizedString datatype (John Belmonte)</li>
1025 <li>code cleanup for strings functions (William)</li>
1026 <li>Windows: compiler patches (Mark Vakoc)</li>
1027 <li>Parser optimizations, a few new XPath and dictionnary APIs for future
1028 XSLT optimizations.</li>
1029</ul>
1030
Daniel Veillarde6e59cd2003-12-24 11:56:44 +00001031<h3>2.6.4: Dec 24 2003</h3>
1032<ul>
1033 <li>Windows build fixes (Igor Zlatkovic)</li>
Daniel Veillard189f46b2004-01-25 21:03:04 +00001034 <li>Some serious XInclude problems reported by Oleg Paraschenko and</li>
1035 <li>Unix and Makefile packaging fixes (me, William Brack,</li>
Daniel Veillarde6e59cd2003-12-24 11:56:44 +00001036 <li>Documentation improvements (John Fleck, William Brack), example fix
1037 (Lucas Brasilino)</li>
1038 <li>bugfixes: xmlTextReaderExpand() with xmlReaderWalker, XPath handling of
1039 NULL strings (William Brack) , API building reader or parser from
1040 filedescriptor should not close it, changed XPath sorting to be stable
1041 again (William Brack), xmlGetNodePath() generating '(null)' (William
1042 Brack), DTD validation and namespace bug (William Brack), XML Schemas
1043 double inclusion behaviour</li>
1044</ul>
1045
Daniel Veillardc480c4e2003-12-10 13:24:38 +00001046<h3>2.6.3: Dec 10 2003</h3>
1047<ul>
1048 <li>documentation updates and cleanup (DV, William Brack, John Fleck)</li>
1049 <li>added a repository of examples, examples from Aleksey Sanin, Dodji
Daniel Veillarde6e59cd2003-12-24 11:56:44 +00001050 Seketeli, Alfred Mickautsch</li>
Daniel Veillardc480c4e2003-12-10 13:24:38 +00001051 <li>Windows updates: Mark Vakoc, Igor Zlatkovic, Eric Zurcher, Mingw
1052 (Kenneth Haley)</li>
1053 <li>Unicode range checking (William Brack)</li>
1054 <li>code cleanup (William Brack)</li>
1055 <li>Python bindings: doc (John Fleck), bug fixes</li>
1056 <li>UTF-16 cleanup and BOM issues (William Brack)</li>
1057 <li>bug fixes: ID and xmlReader validation, XPath (William Brack),
1058 xmlWriter (Alfred Mickautsch), hash.h inclusion problem, HTML parser
1059 (James Bursa), attribute defaulting and validation, some serialization
1060 cleanups, XML_GET_LINE macro, memory debug when using threads (William
1061 Brack), serialization of attributes and entities content, xmlWriter
1062 (Daniel Schulman)</li>
1063 <li>XInclude bugfix, new APIs and update to the last version including the
1064 namespace change.</li>
1065 <li>XML Schemas improvements: include (Robert Stepanek), import and
1066 namespace handling, fixed the regression tests troubles, added examples
Daniel Veillarde6e59cd2003-12-24 11:56:44 +00001067 based on Eric van der Vlist book, regexp fixes</li>
Daniel Veillardc480c4e2003-12-10 13:24:38 +00001068 <li>preliminary pattern support for streaming (needed for schemas
1069 constraints), added xmlTextReaderPreservePattern() to collect subdocument
1070 when streaming.</li>
1071 <li>various fixes in the structured error handling</li>
1072</ul>
1073
Daniel Veillard6d373a22003-11-04 10:26:43 +00001074<h3>2.6.2: Nov 4 2003</h3>
1075<ul>
1076 <li>XPath context unregistration fixes</li>
1077 <li>text node coalescing fixes (Mark Lilback)</li>
1078 <li>API to screate a W3C Schemas from an existing document (Steve Ball)</li>
1079 <li>BeOS patches (Marcin 'Shard' Konicki)</li>
1080 <li>xmlStrVPrintf function added (Aleksey Sanin)</li>
1081 <li>compilation fixes (Mark Vakoc)</li>
1082 <li>stdin parsing fix (William Brack)</li>
1083 <li>a posteriori DTD validation fixes</li>
Daniel Veillardc480c4e2003-12-10 13:24:38 +00001084 <li>xmlReader bug fixes: Walker fixes, python bindings</li>
Daniel Veillard6d373a22003-11-04 10:26:43 +00001085 <li>fixed xmlStopParser() to really stop the parser and errors</li>
1086 <li>always generate line numbers when using the new xmlReadxxx
1087 functions</li>
1088 <li>added XInclude support to the xmlReader interface</li>
1089 <li>implemented XML_PARSE_NONET parser option</li>
1090 <li>DocBook XSLT processing bug fixed</li>
1091 <li>HTML serialization for &lt;p&gt; elements (William Brack and me)</li>
1092 <li>XPointer failure in XInclude are now handled as resource errors</li>
1093 <li>fixed xmllint --html to use the HTML serializer on output (added
1094 --xmlout to implement the previous behaviour of saving it using the XML
1095 serializer)</li>
1096</ul>
1097
Daniel Veillarde4e3f5d2003-10-28 23:06:32 +00001098<h3>2.6.1: Oct 28 2003</h3>
1099<ul>
1100 <li>Mostly bugfixes after the big 2.6.0 changes</li>
1101 <li>Unix compilation patches: libxml.m4 (Patrick Welche), warnings cleanup
1102 (William Brack)</li>
1103 <li>Windows compilation patches (Joachim Bauch, Stephane Bidoul, Igor
1104 Zlatkovic)</li>
1105 <li>xmlWriter bugfix (Alfred Mickautsch)</li>
1106 <li>chvalid.[ch]: couple of fixes from Stephane Bidoul</li>
Daniel Veillard6d373a22003-11-04 10:26:43 +00001107 <li>context reset: error state reset, push parser reset (Graham
1108 Bennett)</li>
Daniel Veillarde4e3f5d2003-10-28 23:06:32 +00001109 <li>context reuse: generate errors if file is not readable</li>
1110 <li>defaulted attributes for element coming from internal entities
1111 (Stephane Bidoul)</li>
1112 <li>Python: tab and spaces mix (William Brack)</li>
1113 <li>Error handler could crash in DTD validation in 2.6.0</li>
1114 <li>xmlReader: do not use the document or element _private field</li>
1115 <li>testSAX.c: avoid a problem with some PIs (Massimo Morara)</li>
1116 <li>general bug fixes: mandatory encoding in text decl, serializing
1117 Document Fragment nodes, xmlSearchNs 2.6.0 problem (Kasimier Buchcik),
1118 XPath errors not reported, slow HTML parsing of large documents.</li>
1119</ul>
1120
Daniel Veillard3e35f8e2003-10-21 00:05:38 +00001121<h3>2.6.0: Oct 20 2003</h3>
1122<ul>
1123 <li>Major revision release: should be API and ABI compatible but got a lot
1124 of change</li>
1125 <li>Increased the library modularity, far more options can be stripped out,
1126 a --with-minimum configuration will weight around 160KBytes</li>
1127 <li>Use per parser and per document dictionnary, allocate names and small
1128 text nodes from the dictionnary</li>
1129 <li>Switch to a SAX2 like parser rewrote most of the XML parser core,
1130 provides namespace resolution and defaulted attributes, minimize memory
1131 allocations and copies, namespace checking and specific error handling,
1132 immutable buffers, make predefined entities static structures, etc...</li>
1133 <li>rewrote all the error handling in the library, all errors can be
1134 intercepted at a structured level, with precise information
1135 available.</li>
1136 <li>New simpler and more generic XML and HTML parser APIs, allowing to
1137 easilly modify the parsing options and reuse parser context for multiple
1138 consecutive documents.</li>
1139 <li>Similar new APIs for the xmlReader, for options and reuse, provided new
1140 functions to access content as const strings, use them for Python
1141 bindings</li>
1142 <li>a lot of other smaller API improvements: xmlStrPrintf (Aleksey Sanin),
1143 Walker i.e. reader on a document tree based on Alfred Mickautsch code,
1144 make room in nodes for line numbers, reference counting and future PSVI
1145 extensions, generation of character ranges to be checked with faster
1146 algorithm (William), xmlParserMaxDepth (Crutcher Dunnavant), buffer
1147 access</li>
1148 <li>New xmlWriter API provided by Alfred Mickautsch</li>
1149 <li>Schemas: base64 support by Anthony Carrico</li>
1150 <li>Parser&lt;-&gt;HTTP integration fix, proper processing of the Mime-Type
1151 and charset informations if available.</li>
1152 <li>Relax-NG: bug fixes including the one reported by Martijn Faassen and
1153 zeroOrMore, better error reporting.</li>
1154 <li>Python bindings (Stéphane Bidoul), never use stdout for errors
1155 output</li>
1156 <li>Portability: all the headers have macros for export and calling
1157 convention definitions (Igor Zlatkovic), VMS update (Craig A. Berry),
1158 Windows: threads (Jesse Pelton), Borland compiler (Eric Zurcher, Igor),
1159 Mingw (Igor), typos (Mark Vakoc), beta version (Stephane Bidoul),
1160 warning cleanups on AIX and MIPS compilers (William Brack), BeOS (Marcin
1161 'Shard' Konicki)</li>
1162 <li>Documentation fixes and README (William Brack), search fix (William),
1163 tutorial updates (John Fleck), namespace docs (Stefan Kost)</li>
1164 <li>Bug fixes: xmlCleanupParser (Dave Beckett), threading uninitialized
1165 mutexes, HTML doctype lowercase, SAX/IO (William), compression detection
1166 and restore (William), attribute declaration in DTDs (William), namespace
1167 on attribute in HTML output (William), input filename (Rob Richards),
1168 namespace DTD validation, xmlReplaceNode (Chris Ryland), I/O callbacks
1169 (Markus Keim), CDATA serialization (Shaun McCance), xmlReader (Peter
1170 Derr), high codepoint charref like &amp;#x10FFFF;, buffer access in push
1171 mode (Justin Fletcher), TLS threads on Windows (Jesse Pelton), XPath bug
1172 (William), xmlCleanupParser (Marc Liyanage), CDATA output (William), HTTP
1173 error handling.</li>
1174 <li>xmllint options: --dtdvalidfpi for Tobias Reif, --sax1 for compat
1175 testing, --nodict for building without tree dictionnary, --nocdata to
1176 replace CDATA by text, --nsclean to remove surperfluous namespace
1177 declarations</li>
1178 <li>added xml2-config --libtool-libs option from Kevin P. Fleming</li>
1179 <li>a lot of profiling and tuning of the code, speedup patch for
1180 xmlSearchNs() by Luca Padovani. The xmlReader should do far less
1181 allocation and it speed should get closer to SAX. Chris Anderson worked
1182 on speeding and cleaning up repetitive checking code.</li>
1183 <li>cleanup of "make tests"</li>
1184 <li>libxml-2.0-uninstalled.pc from Malcolm Tredinnick</li>
1185 <li>deactivated the broken docBook SGML parser code and plugged the XML
1186 parser instead.</li>
1187</ul>
1188
Daniel Veillardeec1ae92003-09-09 13:11:01 +00001189<h3>2.5.11: Sep 9 2003</h3>
1190
1191<p>A bugfix only release:</p>
1192<ul>
1193 <li>risk of crash in Relax-NG</li>
1194 <li>risk of crash when using multithreaded programs</li>
1195</ul>
1196
Daniel Veillardcfba2fe2003-08-15 00:33:43 +00001197<h3>2.5.10: Aug 15 2003</h3>
1198
1199<p>A bugfixes only release</p>
1200<ul>
1201 <li>Windows Makefiles (William Brack)</li>
1202 <li>UTF-16 support fixes (Mark Itzcovitz)</li>
1203 <li>Makefile and portability (William Brack) automake, Linux alpha, Mingw
Daniel Veillardeec1ae92003-09-09 13:11:01 +00001204 on Windows (Mikhail Grushinskiy)</li>
Daniel Veillardcfba2fe2003-08-15 00:33:43 +00001205 <li>HTML parser (Oliver Stoeneberg)</li>
1206 <li>XInclude performance problem reported by Kevin Ruscoe</li>
1207 <li>XML parser performance problem reported by Grant Goodale</li>
1208 <li>xmlSAXParseDTD() bug fix from Malcolm Tredinnick</li>
Daniel Veillardeec1ae92003-09-09 13:11:01 +00001209 <li>and a couple other cleanup</li>
Daniel Veillardcfba2fe2003-08-15 00:33:43 +00001210</ul>
1211
Daniel Veillard83ee40d2003-08-09 22:24:09 +00001212<h3>2.5.9: Aug 9 2003</h3>
1213<ul>
1214 <li>bugfixes: IPv6 portability, xmlHasNsProp (Markus Keim), Windows build
1215 (Wiliam Brake, Jesse Pelton, Igor), Schemas (Peter Sobisch), threading
1216 (Rob Richards), hexBinary type (), UTF-16 BOM (Dodji Seketeli),
1217 xmlReader, Relax-NG schemas compilation, namespace handling, EXSLT (Sean
1218 Griffin), HTML parsing problem (William Brack), DTD validation for mixed
1219 content + namespaces, HTML serialization, library initialization,
1220 progressive HTML parser</li>
1221 <li>better interfaces for Relax-NG error handling (Joachim Bauch, )</li>
1222 <li>adding xmlXIncludeProcessTree() for XInclud'ing in a subtree</li>
1223 <li>doc fixes and improvements (John Fleck)</li>
1224 <li>configure flag for -with-fexceptions when embedding in C++</li>
1225 <li>couple of new UTF-8 helper functions (William Brack)</li>
1226 <li>general encoding cleanup + ISO-8859-x without iconv (Peter Jacobi)</li>
1227 <li>xmlTextReader cleanup + enum for node types (Bjorn Reese)</li>
1228 <li>general compilation/warning cleanup Solaris/HP-UX/... (William
1229 Brack)</li>
1230</ul>
1231
Daniel Veillard560c2a42003-07-06 21:13:49 +00001232<h3>2.5.8: Jul 6 2003</h3>
1233<ul>
1234 <li>bugfixes: XPath, XInclude, file/URI mapping, UTF-16 save (Mark
1235 Itzcovitz), UTF-8 checking, URI saving, error printing (William Brack),
1236 PI related memleak, compilation without schemas or without xpath (Joerg
1237 Schmitz-Linneweber/Garry Pennington), xmlUnlinkNode problem with DTDs,
1238 rpm problem on , i86_64, removed a few compilation problems from 2.5.7,
1239 xmlIOParseDTD, and xmlSAXParseDTD (Malcolm Tredinnick)</li>
1240 <li>portability: DJGPP (MsDos) , OpenVMS (Craig A. Berry)</li>
1241 <li>William Brack fixed multithreading lock problems</li>
1242 <li>IPv6 patch for FTP and HTTP accesses (Archana Shah/Wipro)</li>
1243 <li>Windows fixes (Igor Zlatkovic, Eric Zurcher), threading (Stéphane
1244 Bidoul)</li>
1245 <li>A few W3C Schemas Structure improvements</li>
1246 <li>W3C Schemas Datatype improvements (Charlie Bozeman)</li>
1247 <li>Python bindings for thread globals (Stéphane Bidoul), and method/class
Daniel Veillard83ee40d2003-08-09 22:24:09 +00001248 generator</li>
1249 <li>added --nonet option to xmllint</li>
Daniel Veillard560c2a42003-07-06 21:13:49 +00001250 <li>documentation improvements (John Fleck)</li>
1251</ul>
1252
Daniel Veillard92fc02c2003-04-24 23:12:35 +00001253<h3>2.5.7: Apr 25 2003</h3>
1254<ul>
1255 <li>Relax-NG: Compiling to regexp and streaming validation on top of the
1256 xmlReader interface, added to xmllint --stream</li>
1257 <li>xmlReader: Expand(), Next() and DOM access glue, bug fixes</li>
1258 <li>Support for large files: RGN validated a 4.5GB instance</li>
1259 <li>Thread support is now configured in by default</li>
1260 <li>Fixes: update of the Trio code (Bjorn), WXS Date and Duration fixes
1261 (Charles Bozeman), DTD and namespaces (Brent Hendricks), HTML push parser
1262 and zero bytes handling, some missing Windows file path conversions,
1263 behaviour of the parser and validator in the presence of "out of memory"
Daniel Veillard93d95252003-04-29 20:25:40 +00001264 error conditions</li>
Daniel Veillard92fc02c2003-04-24 23:12:35 +00001265 <li>extended the API to be able to plug a garbage collecting memory
1266 allocator, added xmlMallocAtomic() and modified the allocations
1267 accordingly.</li>
1268 <li>Performances: removed excessive malloc() calls, speedup of the push and
1269 xmlReader interfaces, removed excessive thread locking</li>
1270 <li>Documentation: man page (John Fleck), xmlReader documentation</li>
1271 <li>Python: adding binding for xmlCatalogAddLocal (Brent M Hendricks)</li>
1272</ul>
1273
Daniel Veillardc2d4a932003-04-01 11:13:05 +00001274<h3>2.5.6: Apr 1 2003</h3>
1275<ul>
1276 <li>Fixed W3C XML Schemas datatype, should be compliant now except for
1277 binHex and base64 which are not supported yet.</li>
1278 <li>bug fixes: non-ASCII IDs, HTML output, XInclude on large docs and
1279 XInclude entities handling, encoding detection on external subsets, XML
1280 Schemas bugs and memory leaks, HTML parser (James Bursa)</li>
1281 <li>portability: python/trio (Albert Chin), Sun compiler warnings</li>
1282 <li>documentation: added --relaxng option to xmllint man page (John)</li>
1283 <li>improved error reporting: xml:space, start/end tag mismatches, Relax NG
1284 errors</li>
1285</ul>
1286
1287<h3>2.5.5: Mar 24 2003</h3>
Daniel Veillardd8da01c2003-03-24 15:58:23 +00001288<ul>
1289 <li>Lot of fixes on the Relax NG implementation. More testing including
1290 DocBook and TEI examples.</li>
1291 <li>Increased the support for W3C XML Schemas datatype</li>
1292 <li>Several bug fixes in the URI handling layer</li>
1293 <li>Bug fixes: HTML parser, xmlReader, DTD validation, XPath, encoding
1294 conversion, line counting in the parser.</li>
1295 <li>Added support for $XMLLINT_INDENT environment variable, FTP delete</li>
1296 <li>Fixed the RPM spec file name</li>
1297</ul>
1298
Daniel Veillard17bed982003-02-24 20:11:43 +00001299<h3>2.5.4: Feb 20 2003</h3>
1300<ul>
1301 <li>Conformance testing and lot of fixes on Relax NG and XInclude
1302 implementation</li>
1303 <li>Implementation of XPointer element() scheme</li>
1304 <li>Bug fixes: XML parser, XInclude entities merge, validity checking on
1305 namespaces,
1306 <p>2 serialization bugs, node info generation problems, a DTD regexp
1307 generation problem.</p>
1308 </li>
1309 <li>Portability: windows updates and path canonicalization (Igor)</li>
1310 <li>A few typo fixes (Kjartan Maraas)</li>
1311 <li>Python bindings generator fixes (Stephane Bidoul)</li>
1312</ul>
1313
Daniel Veillard1d788d22003-02-10 16:21:58 +00001314<h3>2.5.3: Feb 10 2003</h3>
1315<ul>
1316 <li>RelaxNG and XML Schemas datatypes improvements, and added a first
1317 version of RelaxNG Python bindings</li>
1318 <li>Fixes: XLink (Sean Chittenden), XInclude (Sean Chittenden), API fix for
1319 serializing namespace nodes, encoding conversion bug, XHTML1
1320 serialization</li>
1321 <li>Portability fixes: Windows (Igor), AMD 64bits RPM spec file</li>
1322</ul>
1323
Daniel Veillard72fef162003-02-05 14:31:19 +00001324<h3>2.5.2: Feb 5 2003</h3>
1325<ul>
1326 <li>First implementation of RelaxNG, added --relaxng flag to xmllint</li>
1327 <li>Schemas support now compiled in by default.</li>
1328 <li>Bug fixes: DTD validation, namespace checking, XInclude and entities,
1329 delegateURI in XML Catalogs, HTML parser, XML reader (Stéphane Bidoul),
1330 XPath parser and evaluation, UTF8ToUTF8 serialization, XML reader memory
1331 consumption, HTML parser, HTML serialization in the presence of
1332 namespaces</li>
1333 <li>added an HTML API to check elements and attributes.</li>
1334 <li>Documentation improvement, PDF for the tutorial (John Fleck), doc
1335 patches (Stefan Kost)</li>
1336 <li>Portability fixes: NetBSD (Julio Merino), Windows (Igor Zlatkovic)</li>
1337 <li>Added python bindings for XPointer, contextual error reporting
1338 (Stéphane Bidoul)</li>
1339 <li>URI/file escaping problems (Stefano Zacchiroli)</li>
Daniel Veillardcf27f7c2002-04-30 07:12:39 +00001340</ul>
1341
Daniel Veillarde2830f12003-01-08 17:47:49 +00001342<h3>2.5.1: Jan 8 2003</h3>
1343<ul>
1344 <li>Fixes a memory leak and configuration/compilation problems in 2.5.0</li>
1345 <li>documentation updates (John)</li>
1346 <li>a couple of XmlTextReader fixes</li>
1347</ul>
1348
Daniel Veillard7b4b2f92003-01-06 13:11:20 +00001349<h3>2.5.0: Jan 6 2003</h3>
1350<ul>
1351 <li>New <a href="xmlreader.html">XmltextReader interface</a> based on C#
1352 API (with help of Stéphane Bidoul)</li>
1353 <li>Windows: more exports, including the new API (Igor)</li>
1354 <li>XInclude fallback fix</li>
1355 <li>Python: bindings for the new API, packaging (Stéphane Bidoul),
1356 drv_libxml2.py Python xml.sax driver (Stéphane Bidoul), fixes, speedup
1357 and iterators for Python-2.2 (Hannu Krosing)</li>
1358 <li>Tutorial fixes (john Fleck and Niraj Tolia) xmllint man update
1359 (John)</li>
1360 <li>Fix an XML parser bug raised by Vyacheslav Pindyura</li>
1361 <li>Fix for VMS serialization (Nigel Hall) and config (Craig A. Berry)</li>
1362 <li>Entities handling fixes</li>
1363 <li>new API to optionally track node creation and deletion (Lukas
1364 Schroeder)</li>
1365 <li>Added documentation for the XmltextReader interface and some <a
1366 href="guidelines.html">XML guidelines</a></li>
1367</ul>
1368
Daniel Veillardc1eed322002-12-12 11:01:32 +00001369<h3>2.4.30: Dec 12 2002</h3>
1370<ul>
1371 <li>2.4.29 broke the python bindings, rereleasing</li>
1372 <li>Improvement/fixes of the XML API generator, and couple of minor code
1373 fixes.</li>
1374</ul>
1375
Daniel Veillard9b4bb4d2002-12-11 19:28:47 +00001376<h3>2.4.29: Dec 11 2002</h3>
1377<ul>
1378 <li>Windows fixes (Igor): Windows CE port, pthread linking, python bindings
1379 (Stéphane Bidoul), Mingw (Magnus Henoch), and export list updates</li>
1380 <li>Fix for prev in python bindings (ERDI Gergo)</li>
1381 <li>Fix for entities handling (Marcus Clarke)</li>
1382 <li>Refactored the XML and HTML dumps to a single code path, fixed XHTML1
1383 dump</li>
1384 <li>Fix for URI parsing when handling URNs with fragment identifiers</li>
1385 <li>Fix for HTTP URL escaping problem</li>
1386 <li>added an TextXmlReader (C#) like API (work in progress)</li>
1387 <li>Rewrote the API in XML generation script, includes a C parser and saves
1388 more informations needed for C# bindings</li>
1389</ul>
1390
Daniel Veillardf9c4cad2002-11-22 15:57:07 +00001391<h3>2.4.28: Nov 22 2002</h3>
1392<ul>
1393 <li>a couple of python binding fixes</li>
1394 <li>2 bug fixes in the XML push parser</li>
1395 <li>potential memory leak removed (Martin Stoilov)</li>
1396 <li>fix to the configure script for Unix (Dimitri Papadopoulos)</li>
1397 <li>added encoding support for XInclude parse="text"</li>
1398 <li>autodetection of XHTML1 and specific serialization rules added</li>
Daniel Veillard9b4bb4d2002-12-11 19:28:47 +00001399 <li>nasty threading bug fixed (William Brack)</li>
Daniel Veillardf9c4cad2002-11-22 15:57:07 +00001400</ul>
1401
Daniel Veillarddad3f682002-11-17 16:47:27 +00001402<h3>2.4.27: Nov 17 2002</h3>
1403<ul>
1404 <li>fixes for the Python bindings</li>
1405 <li>a number of bug fixes: SGML catalogs, xmlParseBalancedChunkMemory(),
1406 HTML parser, Schemas (Charles Bozeman), document fragment support
1407 (Christian Glahn), xmlReconciliateNs (Brian Stafford), XPointer,
1408 xmlFreeNode(), xmlSAXParseMemory (Peter Jones), xmlGetNodePath (Petr
1409 Pajas), entities processing</li>
1410 <li>added grep to xmllint --shell</li>
1411 <li>VMS update patch from Craig A. Berry</li>
1412 <li>cleanup of the Windows build with support for more compilers (Igor),
1413 better thread support on Windows</li>
1414 <li>cleanup of Unix Makefiles and spec file</li>
1415 <li>Improvements to the documentation (John Fleck)</li>
1416</ul>
1417
Daniel Veillard48267432002-10-18 11:21:38 +00001418<h3>2.4.26: Oct 18 2002</h3>
1419<ul>
1420 <li>Patches for Windows CE port, improvements on Windows paths handling</li>
1421 <li>Fixes to the validation code (DTD and Schemas), xmlNodeGetPath() ,
1422 HTML serialization, Namespace compliance, and a number of small
1423 problems</li>
1424</ul>
1425
Daniel Veillarde16b5742002-09-26 17:50:03 +00001426<h3>2.4.25: Sep 26 2002</h3>
1427<ul>
1428 <li>A number of bug fixes: XPath, validation, Python bindings, DOM and
1429 tree, xmlI/O, Html</li>
1430 <li>Serious rewrite of XInclude</li>
1431 <li>Made XML Schemas regexp part of the default build and APIs, small fix
1432 and improvement of the regexp core</li>
1433 <li>Changed the validation code to reuse XML Schemas regexp APIs</li>
1434 <li>Better handling of Windows file paths, improvement of Makefiles (Igor,
1435 Daniel Gehriger, Mark Vakoc)</li>
1436 <li>Improved the python I/O bindings, the tests, added resolver and regexp
Daniel Veillard321be0c2002-10-08 21:26:42 +00001437 APIs</li>
Daniel Veillarde16b5742002-09-26 17:50:03 +00001438 <li>New logos from Marc Liyanage</li>
1439 <li>Tutorial improvements: John Fleck, Christopher Harris</li>
1440 <li>Makefile: Fixes for AMD x86_64 (Mandrake), DESTDIR (Christophe
1441 Merlet)</li>
1442 <li>removal of all stderr/perror use for error reporting</li>
1443 <li>Better error reporting: XPath and DTD validation</li>
1444 <li>update of the trio portability layer (Bjorn Reese)</li>
1445</ul>
1446
Daniel Veillard42766c02002-08-22 20:52:17 +00001447<p><strong>2.4.24: Aug 22 2002</strong></p>
1448<ul>
1449 <li>XPath fixes (William), xf:escape-uri() (Wesley Terpstra)</li>
1450 <li>Python binding fixes: makefiles (William), generator, rpm build, x86-64
1451 (fcrozat)</li>
1452 <li>HTML &lt;style&gt; and boolean attributes serializer fixes</li>
1453 <li>C14N improvements by Aleksey</li>
Daniel Veillarde1662542002-08-28 11:50:59 +00001454 <li>doc cleanups: Rick Jones</li>
Daniel Veillard42766c02002-08-22 20:52:17 +00001455 <li>Windows compiler makefile updates: Igor and Elizabeth Barham</li>
1456 <li>XInclude: implementation of fallback and xml:base fixup added</li>
1457</ul>
1458
Daniel Veillard782afda2002-07-08 15:12:49 +00001459<h3>2.4.23: July 6 2002</h3>
1460<ul>
1461 <li>performances patches: Peter Jacobi</li>
1462 <li>c14n fixes, testsuite and performances: Aleksey Sanin</li>
1463 <li>added xmlDocFormatDump: Chema Celorio</li>
1464 <li>new tutorial: John Fleck</li>
1465 <li>new hash functions and performances: Sander Vesik, portability fix from
1466 Peter Jacobi</li>
1467 <li>a number of bug fixes: XPath (William Brack, Richard Jinks), XML and
1468 HTML parsers, ID lookup function</li>
1469 <li>removal of all remaining sprintf: Aleksey Sanin</li>
1470</ul>
1471
Daniel Veillardc0801af2002-05-28 16:28:42 +00001472<h3>2.4.22: May 27 2002</h3>
1473<ul>
1474 <li>a number of bug fixes: configure scripts, base handling, parser, memory
1475 usage, HTML parser, XPath, documentation (Christian Cornelssen),
Daniel Veillard21473672002-06-17 07:29:22 +00001476 indentation, URI parsing</li>
Daniel Veillardc0801af2002-05-28 16:28:42 +00001477 <li>Optimizations for XMLSec, fixing and making public some of the network
1478 protocol handlers (Aleksey)</li>
1479 <li>performance patch from Gary Pennington</li>
1480 <li>Charles Bozeman provided date and time support for XML Schemas
1481 datatypes</li>
1482</ul>
1483
Daniel Veillardcf27f7c2002-04-30 07:12:39 +00001484<h3>2.4.21: Apr 29 2002</h3>
1485
1486<p>This release is both a bug fix release and also contains the early XML
1487Schemas <a href="http://www.w3.org/TR/xmlschema-1/">structures</a> and <a
1488href="http://www.w3.org/TR/xmlschema-2/">datatypes</a> code, beware, all
1489interfaces are likely to change, there is huge holes, it is clearly a work in
1490progress and don't even think of putting this code in a production system,
Daniel Veillarde6d8e202002-05-02 06:11:10 +00001491it's actually not compiled in by default. The real fixes are:</p>
Daniel Veillardcf27f7c2002-04-30 07:12:39 +00001492<ul>
1493 <li>a couple of bugs or limitations introduced in 2.4.20</li>
1494 <li>patches for Borland C++ and MSC by Igor</li>
1495 <li>some fixes on XPath strings and conformance patches by Richard
1496 Jinks</li>
1497 <li>patch from Aleksey for the ExcC14N specification</li>
1498 <li>OSF/1 bug fix by Bjorn</li>
Daniel Veillardaf43f632002-03-08 15:05:20 +00001499</ul>
1500
Daniel Veillarda7084cd2002-04-15 17:12:47 +00001501<h3>2.4.20: Apr 15 2002</h3>
1502<ul>
Daniel Veillard63d83142002-05-20 06:51:05 +00001503 <li>bug fixes: file descriptor leak, XPath, HTML output, DTD validation</li>
Daniel Veillarda7084cd2002-04-15 17:12:47 +00001504 <li>XPath conformance testing by Richard Jinks</li>
1505 <li>Portability fixes: Solaris, MPE/iX, Windows, OSF/1, python bindings,
1506 libxml.m4</li>
1507</ul>
1508
Daniel Veillard19274092002-03-25 16:48:03 +00001509<h3>2.4.19: Mar 25 2002</h3>
1510<ul>
1511 <li>bug fixes: half a dozen XPath bugs, Validation, ISO-Latin to UTF8
1512 encoder</li>
1513 <li>portability fixes in the HTTP code</li>
Daniel Veillardb2fb8ed2002-04-01 09:33:12 +00001514 <li>memory allocation checks using valgrind, and profiling tests</li>
Daniel Veillard19274092002-03-25 16:48:03 +00001515 <li>revamp of the Windows build and Makefiles</li>
1516</ul>
1517
Daniel Veillard34ce8be2002-03-18 19:37:11 +00001518<h3>2.4.18: Mar 18 2002</h3>
1519<ul>
1520 <li>bug fixes: tree, SAX, canonicalization, validation, portability,
Daniel Veillard63d83142002-05-20 06:51:05 +00001521 XPath</li>
Daniel Veillard34ce8be2002-03-18 19:37:11 +00001522 <li>removed the --with-buffer option it was becoming unmaintainable</li>
1523 <li>serious cleanup of the Python makefiles</li>
1524 <li>speedup patch to XPath very effective for DocBook stylesheets</li>
1525 <li>Fixes for Windows build, cleanup of the documentation</li>
1526</ul>
1527
Daniel Veillardaf43f632002-03-08 15:05:20 +00001528<h3>2.4.17: Mar 8 2002</h3>
1529<ul>
1530 <li>a lot of bug fixes, including "namespace nodes have no parents in
1531 XPath"</li>
1532 <li>fixed/improved the Python wrappers, added more examples and more
1533 regression tests, XPath extension functions can now return node-sets</li>
Daniel Veillard63d83142002-05-20 06:51:05 +00001534 <li>added the XML Canonicalization support from Aleksey Sanin</li>
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +00001535</ul>
1536
Daniel Veillard5f4b5992002-02-20 10:22:49 +00001537<h3>2.4.16: Feb 20 2002</h3>
1538<ul>
1539 <li>a lot of bug fixes, most of them were triggered by the XML Testsuite
1540 from OASIS and W3C. Compliance has been significantly improved.</li>
1541 <li>a couple of portability fixes too.</li>
1542</ul>
1543
Daniel Veillard397ff112002-02-11 18:27:20 +00001544<h3>2.4.15: Feb 11 2002</h3>
1545<ul>
1546 <li>Fixed the Makefiles, especially the python module ones</li>
1547 <li>A few bug fixes and cleanup</li>
1548 <li>Includes cleanup</li>
1549</ul>
1550
Daniel Veillardb6c1e2f2002-02-08 14:52:52 +00001551<h3>2.4.14: Feb 8 2002</h3>
1552<ul>
Daniel Veillard63d83142002-05-20 06:51:05 +00001553 <li>Change of License to the <a
Daniel Veillardb6c1e2f2002-02-08 14:52:52 +00001554 href="http://www.opensource.org/licenses/mit-license.html">MIT
Daniel Veillard63d83142002-05-20 06:51:05 +00001555 License</a> basically for integration in XFree86 codebase, and removing
1556 confusion around the previous dual-licensing</li>
Daniel Veillardb6c1e2f2002-02-08 14:52:52 +00001557 <li>added Python bindings, beta software but should already be quite
1558 complete</li>
1559 <li>a large number of fixes and cleanups, especially for all tree
1560 manipulations</li>
1561 <li>cleanup of the headers, generation of a reference API definition in
1562 XML</li>
1563</ul>
1564
1565<h3>2.4.13: Jan 14 2002</h3>
Daniel Veillard744683d2002-01-14 17:30:20 +00001566<ul>
1567 <li>update of the documentation: John Fleck and Charlie Bozeman</li>
1568 <li>cleanup of timing code from Justin Fletcher</li>
1569 <li>fixes for Windows and initial thread support on Win32: Igor and Serguei
1570 Narojnyi</li>
1571 <li>Cygwin patch from Robert Collins</li>
1572 <li>added xmlSetEntityReferenceFunc() for Keith Isdale work on xsldbg</li>
1573</ul>
1574
Daniel Veillardef90ba72001-12-07 14:24:22 +00001575<h3>2.4.12: Dec 7 2001</h3>
1576<ul>
1577 <li>a few bug fixes: thread (Gary Pennington), xmllint (Geert Kloosterman),
1578 XML parser (Robin Berjon), XPointer (Danny Jamshy), I/O cleanups
1579 (robert)</li>
1580 <li>Eric Lavigne contributed project files for MacOS</li>
1581 <li>some makefiles cleanups</li>
1582</ul>
1583
Daniel Veillarda4871052001-11-26 13:19:48 +00001584<h3>2.4.11: Nov 26 2001</h3>
1585<ul>
1586 <li>fixed a couple of errors in the includes, fixed a few bugs, some code
1587 cleanups</li>
1588 <li>xmllint man pages improvement by Heiko Rupp</li>
1589 <li>updated VMS build instructions from John A Fotheringham</li>
1590 <li>Windows Makefiles updates from Igor</li>
1591</ul>
1592
Daniel Veillard43d3f612001-11-10 11:57:23 +00001593<h3>2.4.10: Nov 10 2001</h3>
1594<ul>
1595 <li>URI escaping fix (Joel Young)</li>
1596 <li>added xmlGetNodePath() (for paths or XPointers generation)</li>
1597 <li>Fixes namespace handling problems when using DTD and validation</li>
1598 <li>improvements on xmllint: Morus Walter patches for --format and
1599 --encode, Stefan Kost and Heiko Rupp improvements on the --shell</li>
1600 <li>fixes for xmlcatalog linking pointed by Weiqi Gao</li>
1601 <li>fixes to the HTML parser</li>
1602</ul>
1603
1604<h3>2.4.9: Nov 6 2001</h3>
1605<ul>
1606 <li>fixes more catalog bugs</li>
1607 <li>avoid a compilation problem, improve xmlGetLineNo()</li>
1608</ul>
1609
Daniel Veillarded421aa2001-11-04 21:22:45 +00001610<h3>2.4.8: Nov 4 2001</h3>
1611<ul>
1612 <li>fixed SGML catalogs broken in previous release, updated xmlcatalog
1613 tool</li>
1614 <li>fixed a compile errors and some includes troubles.</li>
1615</ul>
1616
Daniel Veillard52dcab32001-10-30 12:51:17 +00001617<h3>2.4.7: Oct 30 2001</h3>
1618<ul>
1619 <li>exported some debugging interfaces</li>
1620 <li>serious rewrite of the catalog code</li>
1621 <li>integrated Gary Pennington thread safety patch, added configure option
1622 and regression tests</li>
1623 <li>removed an HTML parser bug</li>
1624 <li>fixed a couple of potentially serious validation bugs</li>
1625 <li>integrated the SGML DocBook support in xmllint</li>
1626 <li>changed the nanoftp anonymous login passwd</li>
1627 <li>some I/O cleanup and a couple of interfaces for Perl wrapper</li>
1628 <li>general bug fixes</li>
1629 <li>updated xmllint man page by John Fleck</li>
1630 <li>some VMS and Windows updates</li>
1631</ul>
1632
Daniel Veillard60087f32001-10-10 09:45:09 +00001633<h3>2.4.6: Oct 10 2001</h3>
1634<ul>
Daniel Veillard52dcab32001-10-30 12:51:17 +00001635 <li>added an updated man pages by John Fleck</li>
Daniel Veillard60087f32001-10-10 09:45:09 +00001636 <li>portability and configure fixes</li>
1637 <li>an infinite loop on the HTML parser was removed (William)</li>
1638 <li>Windows makefile patches from Igor</li>
Daniel Veillard63d83142002-05-20 06:51:05 +00001639 <li>fixed half a dozen bugs reported for libxml or libxslt</li>
Daniel Veillard60087f32001-10-10 09:45:09 +00001640 <li>updated xmlcatalog to be able to modify SGML super catalogs</li>
1641</ul>
1642
Daniel Veillarddadd0872001-09-15 09:21:44 +00001643<h3>2.4.5: Sep 14 2001</h3>
1644<ul>
1645 <li>Remove a few annoying bugs in 2.4.4</li>
1646 <li>forces the HTML serializer to output decimal charrefs since some
1647 version of Netscape can't handle hexadecimal ones</li>
1648</ul>
1649
1650<h3>1.8.16: Sep 14 2001</h3>
1651<ul>
1652 <li>maintenance release of the old libxml1 branch, couple of bug and
1653 portability fixes</li>
1654</ul>
1655
Daniel Veillard04382ae2001-09-12 18:51:30 +00001656<h3>2.4.4: Sep 12 2001</h3>
1657<ul>
1658 <li>added --convert to xmlcatalog, bug fixes and cleanups of XML
1659 Catalog</li>
1660 <li>a few bug fixes and some portability changes</li>
1661 <li>some documentation cleanups</li>
1662</ul>
1663
Daniel Veillard39936902001-08-24 00:49:01 +00001664<h3>2.4.3: Aug 23 2001</h3>
1665<ul>
1666 <li>XML Catalog support see the doc</li>
1667 <li>New NaN/Infinity floating point code</li>
1668 <li>A few bug fixes</li>
1669</ul>
1670
1671<h3>2.4.2: Aug 15 2001</h3>
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +00001672<ul>
1673 <li>adds xmlLineNumbersDefault() to control line number generation</li>
1674 <li>lot of bug fixes</li>
Daniel Veillard63d83142002-05-20 06:51:05 +00001675 <li>the Microsoft MSC projects files should now be up to date</li>
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +00001676 <li>inheritance of namespaces from DTD defaulted attributes</li>
1677 <li>fixes a serious potential security bug</li>
1678 <li>added a --format option to xmllint</li>
1679</ul>
1680
1681<h3>2.4.1: July 24 2001</h3>
1682<ul>
1683 <li>possibility to keep line numbers in the tree</li>
1684 <li>some computation NaN fixes</li>
1685 <li>extension of the XPath API</li>
1686 <li>cleanup for alpha and ia64 targets</li>
1687 <li>patch to allow saving through HTTP PUT or POST</li>
Daniel Veillard09ab7e12001-07-10 15:49:44 +00001688</ul>
1689
1690<h3>2.4.0: July 10 2001</h3>
1691<ul>
1692 <li>Fixed a few bugs in XPath, validation, and tree handling.</li>
Daniel Veillard63d83142002-05-20 06:51:05 +00001693 <li>Fixed XML Base implementation, added a couple of examples to the
Daniel Veillard09ab7e12001-07-10 15:49:44 +00001694 regression tests</li>
1695 <li>A bit of cleanup</li>
Daniel Veillardab8500d2000-10-15 21:06:19 +00001696</ul>
1697
Daniel Veillard5b43fde2001-07-05 23:31:40 +00001698<h3>2.3.14: July 5 2001</h3>
1699<ul>
Daniel Veillard63d83142002-05-20 06:51:05 +00001700 <li>fixed some entities problems and reduce memory requirement when
1701 substituting them</li>
Daniel Veillard5b43fde2001-07-05 23:31:40 +00001702 <li>lots of improvements in the XPath queries interpreter can be
Daniel Veillard63d83142002-05-20 06:51:05 +00001703 substantially faster</li>
Daniel Veillard5b43fde2001-07-05 23:31:40 +00001704 <li>Makefiles and configure cleanups</li>
1705 <li>Fixes to XPath variable eval, and compare on empty node set</li>
1706 <li>HTML tag closing bug fixed</li>
Daniel Veillard63d83142002-05-20 06:51:05 +00001707 <li>Fixed an URI reference computation problem when validating</li>
Daniel Veillard5b43fde2001-07-05 23:31:40 +00001708</ul>
1709
Daniel Veillard2adbb512001-06-28 16:20:36 +00001710<h3>2.3.13: June 28 2001</h3>
1711<ul>
1712 <li>2.3.12 configure.in was broken as well as the push mode XML parser</li>
1713 <li>a few more fixes for compilation on Windows MSC by Yon Derek</li>
1714</ul>
1715
1716<h3>1.8.14: June 28 2001</h3>
1717<ul>
1718 <li>Zbigniew Chyla gave a patch to use the old XML parser in push mode</li>
1719 <li>Small Makefile fix</li>
1720</ul>
1721
Daniel Veillard11648102001-06-26 16:08:24 +00001722<h3>2.3.12: June 26 2001</h3>
1723<ul>
1724 <li>lots of cleanup</li>
1725 <li>a couple of validation fix</li>
1726 <li>fixed line number counting</li>
1727 <li>fixed serious problems in the XInclude processing</li>
1728 <li>added support for UTF8 BOM at beginning of entities</li>
1729 <li>fixed a strange gcc optimizer bugs in xpath handling of float, gcc-3.0
1730 miscompile uri.c (William), Thomas Leitner provided a fix for the
1731 optimizer on Tru64</li>
1732 <li>incorporated Yon Derek and Igor Zlatkovic fixes and improvements for
1733 compilation on Windows MSC</li>
1734 <li>update of libxml-doc.el (Felix Natter)</li>
1735 <li>fixed 2 bugs in URI normalization code</li>
1736</ul>
1737
Daniel Veillarde3c81b52001-06-17 14:50:34 +00001738<h3>2.3.11: June 17 2001</h3>
1739<ul>
1740 <li>updates to trio, Makefiles and configure should fix some portability
1741 problems (alpha)</li>
1742 <li>fixed some HTML serialization problems (pre, script, and block/inline
1743 handling), added encoding aware APIs, cleanup of this code</li>
1744 <li>added xmlHasNsProp()</li>
1745 <li>implemented a specific PI for encoding support in the DocBook SGML
1746 parser</li>
1747 <li>some XPath fixes (-Infinity, / as a function parameter and namespaces
1748 node selection)</li>
1749 <li>fixed a performance problem and an error in the validation code</li>
1750 <li>fixed XInclude routine to implement the recursive behaviour</li>
1751 <li>fixed xmlFreeNode problem when libxml is included statically twice</li>
1752 <li>added --version to xmllint for bug reports</li>
1753</ul>
1754
Daniel Veillard2e4f1882001-06-01 10:11:57 +00001755<h3>2.3.10: June 1 2001</h3>
1756<ul>
1757 <li>fixed the SGML catalog support</li>
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +00001758 <li>a number of reported bugs got fixed, in XPath, iconv detection,
1759 XInclude processing</li>
Daniel Veillard2e4f1882001-06-01 10:11:57 +00001760 <li>XPath string function should now handle unicode correctly</li>
1761</ul>
1762
Daniel Veillard4623acd2001-05-19 15:13:15 +00001763<h3>2.3.9: May 19 2001</h3>
1764
1765<p>Lots of bugfixes, and added a basic SGML catalog support:</p>
1766<ul>
1767 <li>HTML push bugfix #54891 and another patch from Jonas Borgström</li>
Daniel Veillard63d83142002-05-20 06:51:05 +00001768 <li>some serious speed optimization again</li>
Daniel Veillard4623acd2001-05-19 15:13:15 +00001769 <li>some documentation cleanups</li>
Daniel Veillard63d83142002-05-20 06:51:05 +00001770 <li>trying to get better linking on Solaris (-R)</li>
Daniel Veillard4623acd2001-05-19 15:13:15 +00001771 <li>XPath API cleanup from Thomas Broyer</li>
1772 <li>Validation bug fixed #54631, added a patch from Gary Pennington, fixed
1773 xmlValidGetValidElements()</li>
1774 <li>Added an INSTALL file</li>
1775 <li>Attribute removal added to API: #54433</li>
1776 <li>added a basic support for SGML catalogs</li>
1777 <li>fixed xmlKeepBlanksDefault(0) API</li>
1778 <li>bugfix in xmlNodeGetLang()</li>
1779 <li>fixed a small configure portability problem</li>
1780 <li>fixed an inversion of SYSTEM and PUBLIC identifier in HTML document</li>
1781</ul>
1782
Daniel Veillarda265af72001-05-14 11:13:58 +00001783<h3>1.8.13: May 14 2001</h3>
1784<ul>
1785 <li>bugfixes release of the old libxml1 branch used by Gnome</li>
1786</ul>
1787
Daniel Veillard3bbbe6f2001-05-03 11:15:37 +00001788<h3>2.3.8: May 3 2001</h3>
1789<ul>
1790 <li>Integrated an SGML DocBook parser for the Gnome project</li>
1791 <li>Fixed a few things in the HTML parser</li>
1792 <li>Fixed some XPath bugs raised by XSLT use, tried to fix the floating
1793 point portability issue</li>
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +00001794 <li>Speed improvement (8M/s for SAX, 3M/s for DOM, 1.5M/s for
1795 DOM+validation using the XML REC as input and a 700MHz celeron).</li>
Daniel Veillard3bbbe6f2001-05-03 11:15:37 +00001796 <li>incorporated more Windows cleanup</li>
1797 <li>added xmlSaveFormatFile()</li>
1798 <li>fixed problems in copying nodes with entities references (gdome)</li>
1799 <li>removed some troubles surrounding the new validation module</li>
1800</ul>
1801
Daniel Veillarda41123c2001-04-22 19:31:20 +00001802<h3>2.3.7: April 22 2001</h3>
1803<ul>
1804 <li>lots of small bug fixes, corrected XPointer</li>
Daniel Veillard63d83142002-05-20 06:51:05 +00001805 <li>Non deterministic content model validation support</li>
Daniel Veillarda41123c2001-04-22 19:31:20 +00001806 <li>added xmlDocCopyNode for gdome2</li>
1807 <li>revamped the way the HTML parser handles end of tags</li>
Daniel Veillard63d83142002-05-20 06:51:05 +00001808 <li>XPath: corrections of namespaces support and number formatting</li>
Daniel Veillarda41123c2001-04-22 19:31:20 +00001809 <li>Windows: Igor Zlatkovic patches for MSC compilation</li>
Daniel Veillard63d83142002-05-20 06:51:05 +00001810 <li>HTML output fixes from P C Chow and William M. Brack</li>
Daniel Veillarda41123c2001-04-22 19:31:20 +00001811 <li>Improved validation speed sensible for DocBook</li>
1812 <li>fixed a big bug with ID declared in external parsed entities</li>
1813 <li>portability fixes, update of Trio from Bjorn Reese</li>
1814</ul>
1815
Daniel Veillardafc73112001-04-11 11:51:41 +00001816<h3>2.3.6: April 8 2001</h3>
1817<ul>
1818 <li>Code cleanup using extreme gcc compiler warning options, found and
1819 cleared half a dozen potential problem</li>
1820 <li>the Eazel team found an XML parser bug</li>
1821 <li>cleaned up the user of some of the string formatting function. used the
1822 trio library code to provide the one needed when the platform is missing
1823 them</li>
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +00001824 <li>xpath: removed a memory leak and fixed the predicate evaluation
1825 problem, extended the testsuite and cleaned up the result. XPointer seems
1826 broken ...</li>
Daniel Veillardafc73112001-04-11 11:51:41 +00001827</ul>
1828
Daniel Veillard56a4cb82001-03-24 17:00:36 +00001829<h3>2.3.5: Mar 23 2001</h3>
1830<ul>
1831 <li>Biggest change is separate parsing and evaluation of XPath expressions,
1832 there is some new APIs for this too</li>
1833 <li>included a number of bug fixes(XML push parser, 51876, notations,
1834 52299)</li>
1835 <li>Fixed some portability issues</li>
1836</ul>
1837
Daniel Veillarde356c282001-03-10 12:32:04 +00001838<h3>2.3.4: Mar 10 2001</h3>
1839<ul>
1840 <li>Fixed bugs #51860 and #51861</li>
1841 <li>Added a global variable xmlDefaultBufferSize to allow default buffer
1842 size to be application tunable.</li>
1843 <li>Some cleanup in the validation code, still a bug left and this part
1844 should probably be rewritten to support ambiguous content model :-\</li>
1845 <li>Fix a couple of serious bugs introduced or raised by changes in 2.3.3
1846 parser</li>
1847 <li>Fixed another bug in xmlNodeGetContent()</li>
1848 <li>Bjorn fixed XPath node collection and Number formatting</li>
1849 <li>Fixed a loop reported in the HTML parsing</li>
1850 <li>blank space are reported even if the Dtd content model proves that they
Daniel Veillard63d83142002-05-20 06:51:05 +00001851 are formatting spaces, this is for XML conformance</li>
Daniel Veillarde356c282001-03-10 12:32:04 +00001852</ul>
1853
Daniel Veillardb402c072001-03-01 17:28:58 +00001854<h3>2.3.3: Mar 1 2001</h3>
1855<ul>
1856 <li>small change in XPath for XSLT</li>
1857 <li>documentation cleanups</li>
1858 <li>fix in validation by Gary Pennington</li>
1859 <li>serious parsing performances improvements</li>
1860</ul>
1861
Daniel Veillardec70e912001-02-26 20:10:45 +00001862<h3>2.3.2: Feb 24 2001</h3>
Daniel Veillard71681102001-02-24 17:48:53 +00001863<ul>
1864 <li>chasing XPath bugs, found a bunch, completed some TODO</li>
1865 <li>fixed a Dtd parsing bug</li>
1866 <li>fixed a bug in xmlNodeGetContent</li>
1867 <li>ID/IDREF support partly rewritten by Gary Pennington</li>
1868</ul>
1869
Daniel Veillardec70e912001-02-26 20:10:45 +00001870<h3>2.3.1: Feb 15 2001</h3>
Daniel Veillard6e6a6cc2001-02-15 15:55:44 +00001871<ul>
1872 <li>some XPath and HTML bug fixes for XSLT</li>
1873 <li>small extension of the hash table interfaces for DOM gdome2
1874 implementation</li>
1875 <li>A few bug fixes</li>
1876</ul>
1877
Daniel Veillardec70e912001-02-26 20:10:45 +00001878<h3>2.3.0: Feb 8 2001 (2.2.12 was on 25 Jan but I didn't kept track)</h3>
Daniel Veillard6e6a6cc2001-02-15 15:55:44 +00001879<ul>
1880 <li>Lots of XPath bug fixes</li>
1881 <li>Add a mode with Dtd lookup but without validation error reporting for
1882 XSLT</li>
1883 <li>Add support for text node without escaping (XSLT)</li>
1884 <li>bug fixes for xmlCheckFilename</li>
1885 <li>validation code bug fixes from Gary Pennington</li>
1886 <li>Patch from Paul D. Smith correcting URI path normalization</li>
1887 <li>Patch to allow simultaneous install of libxml-devel and
1888 libxml2-devel</li>
1889 <li>the example Makefile is now fixed</li>
1890 <li>added HTML to the RPM packages</li>
1891 <li>tree copying bugfixes</li>
1892 <li>updates to Windows makefiles</li>
Daniel Veillard63d83142002-05-20 06:51:05 +00001893 <li>optimization patch from Bjorn Reese</li>
Daniel Veillard6e6a6cc2001-02-15 15:55:44 +00001894</ul>
1895
Daniel Veillardec70e912001-02-26 20:10:45 +00001896<h3>2.2.11: Jan 4 2001</h3>
Daniel Veillard503b8932001-01-05 06:36:31 +00001897<ul>
1898 <li>bunch of bug fixes (memory I/O, xpath, ftp/http, ...)</li>
1899 <li>added htmlHandleOmittedElem()</li>
1900 <li>Applied Bjorn Reese's IPV6 first patch</li>
1901 <li>Applied Paul D. Smith patches for validation of XInclude results</li>
Daniel Veillard82687162001-01-22 15:32:01 +00001902 <li>added XPointer xmlns() new scheme support</li>
Daniel Veillard503b8932001-01-05 06:36:31 +00001903</ul>
1904
Daniel Veillard2ddd23d2000-11-25 10:42:19 +00001905<h3>2.2.10: Nov 25 2000</h3>
Daniel Veillard9d343c42000-11-25 10:12:43 +00001906<ul>
1907 <li>Fix the Windows problems of 2.2.8</li>
1908 <li>integrate OpenVMS patches</li>
1909 <li>better handling of some nasty HTML input</li>
1910 <li>Improved the XPointer implementation</li>
1911 <li>integrate a number of provided patches</li>
1912</ul>
1913
Daniel Veillard2ddd23d2000-11-25 10:42:19 +00001914<h3>2.2.9: Nov 25 2000</h3>
1915<ul>
1916 <li>erroneous release :-(</li>
1917</ul>
1918
Daniel Veillard28929b22000-11-13 18:22:49 +00001919<h3>2.2.8: Nov 13 2000</h3>
1920<ul>
1921 <li>First version of <a href="http://www.w3.org/TR/xinclude">XInclude</a>
1922 support</li>
1923 <li>Patch in conditional section handling</li>
1924 <li>updated MS compiler project</li>
1925 <li>fixed some XPath problems</li>
1926 <li>added an URI escaping function</li>
1927 <li>some other bug fixes</li>
1928</ul>
1929
1930<h3>2.2.7: Oct 31 2000</h3>
1931<ul>
1932 <li>added message redirection</li>
1933 <li>XPath improvements (thanks TOM !)</li>
1934 <li>xmlIOParseDTD() added</li>
1935 <li>various small fixes in the HTML, URI, HTTP and XPointer support</li>
1936 <li>some cleanup of the Makefile, autoconf and the distribution content</li>
1937</ul>
1938
Daniel Veillard29a11cc2000-10-25 13:32:39 +00001939<h3>2.2.6: Oct 25 2000:</h3>
1940<ul>
1941 <li>Added an hash table module, migrated a number of internal structure to
1942 those</li>
1943 <li>Fixed a posteriori validation problems</li>
1944 <li>HTTP module cleanups</li>
1945 <li>HTML parser improvements (tag errors, script/style handling, attribute
1946 normalization)</li>
1947 <li>coalescing of adjacent text nodes</li>
1948 <li>couple of XPath bug fixes, exported the internal API</li>
1949</ul>
1950
Daniel Veillardab8500d2000-10-15 21:06:19 +00001951<h3>2.2.5: Oct 15 2000:</h3>
Daniel Veillard4c3a2031999-11-19 17:46:26 +00001952<ul>
Daniel Veillard189446d2000-10-13 10:23:06 +00001953 <li>XPointer implementation and testsuite</li>
1954 <li>Lot of XPath fixes, added variable and functions registration, more
1955 tests</li>
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +00001956 <li>Portability fixes, lots of enhancements toward an easy Windows build
1957 and release</li>
Daniel Veillard189446d2000-10-13 10:23:06 +00001958 <li>Late validation fixes</li>
1959 <li>Integrated a lot of contributed patches</li>
1960 <li>added memory management docs</li>
Daniel Veillardab8500d2000-10-15 21:06:19 +00001961 <li>a performance problem when using large buffer seems fixed</li>
Daniel Veillard189446d2000-10-13 10:23:06 +00001962</ul>
1963
1964<h3>2.2.4: Oct 1 2000:</h3>
1965<ul>
1966 <li>main XPath problem fixed</li>
1967 <li>Integrated portability patches for Windows</li>
1968 <li>Serious bug fixes on the URI and HTML code</li>
Daniel Veillard361d8452000-04-03 19:48:13 +00001969</ul>
1970
Daniel Veillardd5f97f82000-09-17 16:38:14 +00001971<h3>2.2.3: Sep 17 2000</h3>
1972<ul>
1973 <li>bug fixes</li>
1974 <li>cleanup of entity handling code</li>
1975 <li>overall review of all loops in the parsers, all sprintf usage has been
1976 checked too</li>
Daniel Veillard63d83142002-05-20 06:51:05 +00001977 <li>Far better handling of larges Dtd. Validating against DocBook XML Dtd
Daniel Veillardd5f97f82000-09-17 16:38:14 +00001978 works smoothly now.</li>
1979</ul>
1980
1981<h3>1.8.10: Sep 6 2000</h3>
1982<ul>
1983 <li>bug fix release for some Gnome projects</li>
1984</ul>
1985
1986<h3>2.2.2: August 12 2000</h3>
Daniel Veillard786d7c82000-08-12 23:38:57 +00001987<ul>
1988 <li>mostly bug fixes</li>
Daniel Veillardec78c0f2000-08-25 10:25:23 +00001989 <li>started adding routines to access xml parser context options</li>
Daniel Veillard786d7c82000-08-12 23:38:57 +00001990</ul>
1991
Daniel Veillardd5f97f82000-09-17 16:38:14 +00001992<h3>2.2.1: July 21 2000</h3>
Daniel Veillarda2679fa2000-07-22 02:38:15 +00001993<ul>
1994 <li>a purely bug fixes release</li>
1995 <li>fixed an encoding support problem when parsing from a memory block</li>
1996 <li>fixed a DOCTYPE parsing problem</li>
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +00001997 <li>removed a bug in the function allowing to override the memory
1998 allocation routines</li>
Daniel Veillarda2679fa2000-07-22 02:38:15 +00001999</ul>
2000
Daniel Veillardd5f97f82000-09-17 16:38:14 +00002001<h3>2.2.0: July 14 2000</h3>
Daniel Veillard94e90602000-07-17 14:38:19 +00002002<ul>
2003 <li>applied a lot of portability fixes</li>
2004 <li>better encoding support/cleanup and saving (content is now always
2005 encoded in UTF-8)</li>
2006 <li>the HTML parser now correctly handles encodings</li>
2007 <li>added xmlHasProp()</li>
2008 <li>fixed a serious problem with &amp;#38;</li>
2009 <li>propagated the fix to FTP client</li>
2010 <li>cleanup, bugfixes, etc ...</li>
2011 <li>Added a page about <a href="encoding.html">libxml Internationalization
2012 support</a></li>
2013</ul>
2014
Daniel Veillard60979bd2000-07-10 12:17:33 +00002015<h3>1.8.9: July 9 2000</h3>
2016<ul>
2017 <li>fixed the spec the RPMs should be better</li>
2018 <li>fixed a serious bug in the FTP implementation, released 1.8.9 to solve
2019 rpmfind users problem</li>
2020</ul>
2021
Daniel Veillard6388e172000-07-03 16:07:19 +00002022<h3>2.1.1: July 1 2000</h3>
2023<ul>
2024 <li>fixes a couple of bugs in the 2.1.0 packaging</li>
2025 <li>improvements on the HTML parser</li>
2026</ul>
2027
Daniel Veillard3f6f7f62000-06-30 17:58:25 +00002028<h3>2.1.0 and 1.8.8: June 29 2000</h3>
2029<ul>
Daniel Veillardc0801af2002-05-28 16:28:42 +00002030 <li>1.8.8 is mostly a commodity package for upgrading to libxml2 according
2031 to <a href="upgrade.html">new instructions</a>. It fixes a nasty problem
Daniel Veillard3f6f7f62000-06-30 17:58:25 +00002032 about &amp;#38; charref parsing</li>
2033 <li>2.1.0 also ease the upgrade from libxml v1 to the recent version. it
2034 also contains numerous fixes and enhancements:
2035 <ul>
2036 <li>added xmlStopParser() to stop parsing</li>
2037 <li>improved a lot parsing speed when there is large CDATA blocs</li>
2038 <li>includes XPath patches provided by Picdar Technology</li>
Daniel Veillard63d83142002-05-20 06:51:05 +00002039 <li>tried to fix as much as possible DTD validation and namespace
Daniel Veillard3f6f7f62000-06-30 17:58:25 +00002040 related problems</li>
2041 <li>output to a given encoding has been added/tested</li>
2042 <li>lot of various fixes</li>
2043 </ul>
2044 </li>
2045</ul>
2046
Daniel Veillarde0aed302000-04-16 08:52:20 +00002047<h3>2.0.0: Apr 12 2000</h3>
Daniel Veillard361d8452000-04-03 19:48:13 +00002048<ul>
2049 <li>First public release of libxml2. If you are using libxml, it's a good
Daniel Veillard63d83142002-05-20 06:51:05 +00002050 idea to check the 1.x to 2.x upgrade instructions. NOTE: while initially
2051 scheduled for Apr 3 the release occurred only on Apr 12 due to massive
Daniel Veillarde0aed302000-04-16 08:52:20 +00002052 workload.</li>
Daniel Veillard361d8452000-04-03 19:48:13 +00002053 <li>The include are now located under $prefix/include/libxml (instead of
Daniel Veillarde0aed302000-04-16 08:52:20 +00002054 $prefix/include/gnome-xml), they also are referenced by
Daniel Veillard60979bd2000-07-10 12:17:33 +00002055 <pre>#include &lt;libxml/xxx.h&gt;</pre>
Daniel Veillarde0aed302000-04-16 08:52:20 +00002056 <p>instead of</p>
Daniel Veillard361d8452000-04-03 19:48:13 +00002057 <pre>#include "xxx.h"</pre>
2058 </li>
Daniel Veillard8f621982000-03-20 13:07:15 +00002059 <li>a new URI module for parsing URIs and following strictly RFC 2396</li>
2060 <li>the memory allocation routines used by libxml can now be overloaded
2061 dynamically by using xmlMemSetup()</li>
Daniel Veillard361d8452000-04-03 19:48:13 +00002062 <li>The previously CVS only tool tester has been renamed
2063 <strong>xmllint</strong> and is now installed as part of the libxml2
2064 package</li>
Daniel Veillarde0aed302000-04-16 08:52:20 +00002065 <li>The I/O interface has been revamped. There is now ways to plug in
2066 specific I/O modules, either at the URI scheme detection level using
2067 xmlRegisterInputCallbacks() or by passing I/O functions when creating a
2068 parser context using xmlCreateIOParserCtxt()</li>
2069 <li>there is a C preprocessor macro LIBXML_VERSION providing the version
2070 number of the libxml module in use</li>
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +00002071 <li>a number of optional features of libxml can now be excluded at
2072 configure time (FTP/HTTP/HTML/XPath/Debug)</li>
Daniel Veillardedfb29b2000-03-14 19:59:05 +00002073</ul>
2074
2075<h3>2.0.0beta: Mar 14 2000</h3>
2076<ul>
2077 <li>This is a first Beta release of libxml version 2</li>
Daniel Veillarde356c282001-03-10 12:32:04 +00002078 <li>It's available only from<a href="ftp://xmlsoft.org/">xmlsoft.org
2079 FTP</a>, it's packaged as libxml2-2.0.0beta and available as tar and
2080 RPMs</li>
Daniel Veillardedfb29b2000-03-14 19:59:05 +00002081 <li>This version is now the head in the Gnome CVS base, the old one is
2082 available under the tag LIB_XML_1_X</li>
Daniel Veillardc0801af2002-05-28 16:28:42 +00002083 <li>This includes a very large set of changes. From a programmatic point
2084 of view applications should not have to be modified too much, check the
2085 <a href="upgrade.html">upgrade page</a></li>
Daniel Veillardedfb29b2000-03-14 19:59:05 +00002086 <li>Some interfaces may changes (especially a bit about encoding).</li>
2087 <li>the updates includes:
Daniel Veillard6c8b1172000-03-01 00:40:41 +00002088 <ul>
Daniel Veillardedfb29b2000-03-14 19:59:05 +00002089 <li>fix I18N support. ISO-Latin-x/UTF-8/UTF-16 (nearly) seems correctly
2090 handled now</li>
Daniel Veillard63d83142002-05-20 06:51:05 +00002091 <li>Better handling of entities, especially well-formedness checking
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +00002092 and proper PEref extensions in external subsets</li>
Daniel Veillard6c8b1172000-03-01 00:40:41 +00002093 <li>DTD conditional sections</li>
Daniel Veillard63d83142002-05-20 06:51:05 +00002094 <li>Validation now correctly handle entities content</li>
Daniel Veillard6c8b1172000-03-01 00:40:41 +00002095 <li><a href="http://rpmfind.net/tools/gdome/messages/0039.html">change
Daniel Veillard63d83142002-05-20 06:51:05 +00002096 structures to accommodate DOM</a></li>
Daniel Veillard6c8b1172000-03-01 00:40:41 +00002097 </ul>
2098 </li>
Daniel Veillardedfb29b2000-03-14 19:59:05 +00002099 <li>Serious progress were made toward compliance, <a
2100 href="conf/result.html">here are the result of the test</a> against the
Daniel Veillard63d83142002-05-20 06:51:05 +00002101 OASIS testsuite (except the Japanese tests since I don't support that
Daniel Veillardedfb29b2000-03-14 19:59:05 +00002102 encoding yet). This URL is rebuilt every couple of hours using the CVS
2103 head version.</li>
Daniel Veillarde41f2b72000-01-30 20:00:07 +00002104</ul>
2105
Daniel Veillardf13e1ed2000-03-06 07:41:49 +00002106<h3>1.8.7: Mar 6 2000</h3>
2107<ul>
2108 <li>This is a bug fix release:</li>
2109 <li>It is possible to disable the ignorable blanks heuristic used by
2110 libxml-1.x, a new function xmlKeepBlanksDefault(0) will allow this. Note
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +00002111 that for adherence to XML spec, this behaviour will be disabled by
2112 default in 2.x . The same function will allow to keep compatibility for
2113 old code.</li>
Daniel Veillard60979bd2000-07-10 12:17:33 +00002114 <li>Blanks in &lt;a&gt; &lt;/a&gt; constructs are not ignored anymore,
2115 avoiding heuristic is really the Right Way :-\</li>
Daniel Veillardf13e1ed2000-03-06 07:41:49 +00002116 <li>The unchecked use of snprintf which was breaking libxml-1.8.6
2117 compilation on some platforms has been fixed</li>
2118 <li>nanoftp.c nanohttp.c: Fixed '#' and '?' stripping when processing
2119 URIs</li>
2120</ul>
2121
Daniel Veillarde41f2b72000-01-30 20:00:07 +00002122<h3>1.8.6: Jan 31 2000</h3>
2123<ul>
2124 <li>added a nanoFTP transport module, debugged until the new version of <a
2125 href="http://rpmfind.net/linux/rpm2html/rpmfind.html">rpmfind</a> can use
2126 it without troubles</li>
Daniel Veillardda07c342000-01-25 18:31:22 +00002127</ul>
2128
2129<h3>1.8.5: Jan 21 2000</h3>
2130<ul>
Daniel Veillard0142b842000-01-14 14:45:24 +00002131 <li>adding APIs to parse a well balanced chunk of XML (production <a
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +00002132 href="http://www.w3.org/TR/REC-xml#NT-content">[43] content</a> of the
2133 XML spec)</li>
Daniel Veillard461a66c2000-01-18 18:01:01 +00002134 <li>fixed a hideous bug in xmlGetProp pointed by Rune.Djurhuus@fast.no</li>
Daniel Veillard60979bd2000-07-10 12:17:33 +00002135 <li>Jody Goldberg &lt;jgoldberg@home.com&gt; provided another patch trying
2136 to solve the zlib checks problems</li>
Daniel Veillard461a66c2000-01-18 18:01:01 +00002137 <li>The current state in gnome CVS base is expected to ship as 1.8.5 with
2138 gnumeric soon</li>
Daniel Veillard0142b842000-01-14 14:45:24 +00002139</ul>
2140
2141<h3>1.8.4: Jan 13 2000</h3>
2142<ul>
2143 <li>bug fixes, reintroduced xmlNewGlobalNs(), fixed xmlNewNs()</li>
2144 <li>all exit() call should have been removed from libxml</li>
2145 <li>fixed a problem with INCLUDE_WINSOCK on WIN32 platform</li>
2146 <li>added newDocFragment()</li>
Daniel Veillardf84f71f2000-01-05 19:54:23 +00002147</ul>
2148
2149<h3>1.8.3: Jan 5 2000</h3>
2150<ul>
2151 <li>a Push interface for the XML and HTML parsers</li>
Daniel Veillardf13e1ed2000-03-06 07:41:49 +00002152 <li>a shell-like interface to the document tree (try tester --shell :-)</li>
Daniel Veillard63d83142002-05-20 06:51:05 +00002153 <li>lots of bug fixes and improvement added over XMas holidays</li>
Daniel Veillard437b87b2000-01-03 17:30:46 +00002154 <li>fixed the DTD parsing code to work with the xhtml DTD</li>
Daniel Veillardf84f71f2000-01-05 19:54:23 +00002155 <li>added xmlRemoveProp(), xmlRemoveID() and xmlRemoveRef()</li>
2156 <li>Fixed bugs in xmlNewNs()</li>
Daniel Veillard437b87b2000-01-03 17:30:46 +00002157 <li>External entity loading code has been revamped, now it uses
Daniel Veillardf84f71f2000-01-05 19:54:23 +00002158 xmlLoadExternalEntity(), some fix on entities processing were added</li>
Daniel Veillard437b87b2000-01-03 17:30:46 +00002159 <li>cleaned up WIN32 includes of socket stuff</li>
Daniel Veillard5cb5ab81999-12-21 15:35:29 +00002160</ul>
2161
2162<h3>1.8.2: Dec 21 1999</h3>
2163<ul>
Daniel Veillardb24054a1999-12-18 15:32:46 +00002164 <li>I got another problem with includes and C++, I hope this issue is fixed
2165 for good this time</li>
Daniel Veillard5cb5ab81999-12-21 15:35:29 +00002166 <li>Added a few tree modification functions: xmlReplaceNode,
2167 xmlAddPrevSibling, xmlAddNextSibling, xmlNodeSetName and
2168 xmlDocSetRootElement</li>
2169 <li>Tried to improve the HTML output with help from <a
2170 href="mailto:clahey@umich.edu">Chris Lahey</a></li>
Daniel Veillarde4e51311999-12-18 15:32:46 +00002171</ul>
Daniel Veillardb24054a1999-12-18 15:32:46 +00002172
Daniel Veillarde4e51311999-12-18 15:32:46 +00002173<h3>1.8.1: Dec 18 1999</h3>
2174<ul>
2175 <li>various patches to avoid troubles when using libxml with C++ compilers
2176 the "namespace" keyword and C escaping in include files</li>
2177 <li>a problem in one of the core macros IS_CHAR was corrected</li>
2178 <li>fixed a bug introduced in 1.8.0 breaking default namespace processing,
2179 and more specifically the Dia application</li>
Daniel Veillard944b5ff1999-12-15 19:08:24 +00002180 <li>fixed a posteriori validation (validation after parsing, or by using a
2181 Dtd not specified in the original document)</li>
Daniel Veillardb24054a1999-12-18 15:32:46 +00002182 <li>fixed a bug in</li>
Daniel Veillard10a2c651999-12-12 13:03:50 +00002183</ul>
2184
2185<h3>1.8.0: Dec 12 1999</h3>
2186<ul>
2187 <li>cleanup, especially memory wise</li>
2188 <li>the parser should be more reliable, especially the HTML one, it should
2189 not crash, whatever the input !</li>
2190 <li>Integrated various patches, especially a speedup improvement for large
2191 dataset from <a href="mailto:cnygard@bellatlantic.net">Carl Nygard</a>,
2192 configure with --with-buffers to enable them.</li>
2193 <li>attribute normalization, oops should have been added long ago !</li>
Daniel Veillard63d83142002-05-20 06:51:05 +00002194 <li>attributes defaulted from DTDs should be available, xmlSetProp() now
2195 does entities escaping by default.</li>
Daniel Veillard4c3a2031999-11-19 17:46:26 +00002196</ul>
Daniel Veillard35008381999-10-25 13:15:52 +00002197
2198<h3>1.7.4: Oct 25 1999</h3>
Daniel Veillard2f4dfc41999-09-24 14:03:48 +00002199<ul>
Daniel Veillard35008381999-10-25 13:15:52 +00002200 <li>Lots of HTML improvement</li>
2201 <li>Fixed some errors when saving both XML and HTML</li>
2202 <li>More examples, the regression tests should now look clean</li>
2203 <li>Fixed a bug with contiguous charref</li>
2204</ul>
2205
2206<h3>1.7.3: Sep 29 1999</h3>
2207<ul>
2208 <li>portability problems fixed</li>
Daniel Veillard63d83142002-05-20 06:51:05 +00002209 <li>snprintf was used unconditionally, leading to link problems on system
Daniel Veillard35008381999-10-25 13:15:52 +00002210 were it's not available, fixed</li>
Daniel Veillard2f4dfc41999-09-24 14:03:48 +00002211</ul>
2212
2213<h3>1.7.1: Sep 24 1999</h3>
2214<ul>
2215 <li>The basic type for strings manipulated by libxml has been renamed in
2216 1.7.1 from <strong>CHAR</strong> to <strong>xmlChar</strong>. The reason
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +00002217 is that CHAR was conflicting with a predefined type on Windows. However
2218 on non WIN32 environment, compatibility is provided by the way of a
Daniel Veillard2f4dfc41999-09-24 14:03:48 +00002219 <strong>#define </strong>.</li>
2220 <li>Changed another error : the use of a structure field called errno, and
2221 leading to troubles on platforms where it's a macro</li>
2222</ul>
2223
Daniel Veillard63d83142002-05-20 06:51:05 +00002224<h3>1.7.0: Sep 23 1999</h3>
Daniel Veillard2f4dfc41999-09-24 14:03:48 +00002225<ul>
2226 <li>Added the ability to fetch remote DTD or parsed entities, see the <a
Daniel Veillard9cb5ff42001-01-29 08:22:21 +00002227 href="html/libxml-nanohttp.html">nanohttp</a> module.</li>
Daniel Veillard2f4dfc41999-09-24 14:03:48 +00002228 <li>Added an errno to report errors by another mean than a simple printf
2229 like callback</li>
2230 <li>Finished ID/IDREF support and checking when validation</li>
2231 <li>Serious memory leaks fixed (there is now a <a
Daniel Veillard9cb5ff42001-01-29 08:22:21 +00002232 href="html/libxml-xmlmemory.html">memory wrapper</a> module)</li>
Daniel Veillard2f4dfc41999-09-24 14:03:48 +00002233 <li>Improvement of <a href="http://www.w3.org/TR/xpath">XPath</a>
2234 implementation</li>
2235 <li>Added an HTML parser front-end</li>
2236</ul>
2237
2238<h2><a name="XML">XML</a></h2>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +00002239
Daniel Veillard402e8c82000-02-29 22:57:47 +00002240<p><a href="http://www.w3.org/TR/REC-xml">XML is a standard</a> for
Daniel Veillardf13e1ed2000-03-06 07:41:49 +00002241markup-based structured documents. Here is <a name="example">an example XML
2242document</a>:</p>
Daniel Veillard60979bd2000-07-10 12:17:33 +00002243<pre>&lt;?xml version="1.0"?&gt;
2244&lt;EXAMPLE prop1="gnome is great" prop2="&amp;amp; linux too"&gt;
2245 &lt;head&gt;
2246 &lt;title&gt;Welcome to Gnome&lt;/title&gt;
2247 &lt;/head&gt;
2248 &lt;chapter&gt;
2249 &lt;title&gt;The Linux adventure&lt;/title&gt;
2250 &lt;p&gt;bla bla bla ...&lt;/p&gt;
2251 &lt;image href="linus.gif"/&gt;
2252 &lt;p&gt;...&lt;/p&gt;
2253 &lt;/chapter&gt;
2254&lt;/EXAMPLE&gt;</pre>
Daniel Veillardb05deb71999-08-10 19:04:08 +00002255
Daniel Veillard0b28e882002-07-24 23:47:05 +00002256<p>The first line specifies that it is an XML document and gives useful
Daniel Veillard42766c02002-08-22 20:52:17 +00002257information about its encoding. Then the rest of the document is a text
2258format whose structure is specified by tags between brackets. <strong>Each
2259tag opened has to be closed</strong>. XML is pedantic about this. However, if
2260a tag is empty (no content), a single tag can serve as both the opening and
2261closing tag if it ends with <code>/&gt;</code> rather than with
2262<code>&gt;</code>. Note that, for example, the image tag has no content (just
2263an attribute) and is closed by ending the tag with <code>/&gt;</code>.</p>
Daniel Veillardccb09631998-10-27 06:21:04 +00002264
Daniel Veillard42766c02002-08-22 20:52:17 +00002265<p>XML can be applied successfully to a wide range of tasks, ranging from
2266long term structured document maintenance (where it follows the steps of
2267SGML) to simple data encoding mechanisms like configuration file formatting
2268(glade), spreadsheets (gnumeric), or even shorter lived documents such as
2269WebDAV where it is used to encode remote calls between a client and a
2270server.</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +00002271
Daniel Veillard82687162001-01-22 15:32:01 +00002272<h2><a name="XSLT">XSLT</a></h2>
2273
Daniel Veillard6e6a6cc2001-02-15 15:55:44 +00002274<p>Check <a href="http://xmlsoft.org/XSLT">the separate libxslt page</a></p>
2275
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +00002276<p><a href="http://www.w3.org/TR/xslt">XSL Transformations</a>, is a
2277language for transforming XML documents into other XML documents (or
2278HTML/textual output).</p>
Daniel Veillard82687162001-01-22 15:32:01 +00002279
Daniel Veillard560c2a42003-07-06 21:13:49 +00002280<p>A separate library called libxslt is available implementing XSLT-1.0 for
2281libxml2. This module "libxslt" too can be found in the Gnome CVS base.</p>
Daniel Veillard82687162001-01-22 15:32:01 +00002282
Daniel Veillard383b1472001-01-23 11:39:52 +00002283<p>You can check the <a
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +00002284href="http://cvs.gnome.org/lxr/source/libxslt/FEATURES">features</a>
2285supported and the progresses on the <a
Daniel Veillard6dbcaf82002-02-20 14:37:47 +00002286href="http://cvs.gnome.org/lxr/source/libxslt/ChangeLog"
Daniel Veillard0b28e882002-07-24 23:47:05 +00002287name="Changelog">Changelog</a>.</p>
Daniel Veillard6dbcaf82002-02-20 14:37:47 +00002288
2289<h2><a name="Python">Python and bindings</a></h2>
2290
Daniel Veillard42766c02002-08-22 20:52:17 +00002291<p>There are a number of language bindings and wrappers available for
2292libxml2, the list below is not exhaustive. Please contact the <a
Daniel Veillard6dbcaf82002-02-20 14:37:47 +00002293href="http://mail.gnome.org/mailman/listinfo/xml-bindings">xml-bindings@gnome.org</a>
2294(<a href="http://mail.gnome.org/archives/xml-bindings/">archives</a>) in
2295order to get updates to this list or to discuss the specific topic of libxml2
2296or libxslt wrappers or bindings:</p>
2297<ul>
Daniel Veillardc14401e2002-11-20 14:28:17 +00002298 <li><a href="http://libxmlplusplus.sourceforge.net/">Libxml++</a> seems the
2299 most up-to-date C++ bindings for libxml2, check the <a
2300 href="http://libxmlplusplus.sourceforge.net/reference/html/hierarchy.html">documentation</a>
2301 and the <a
2302 href="http://cvs.sourceforge.net/cgi-bin/viewcvs.cgi/libxmlplusplus/libxml%2b%2b/examples/">examples</a>.</li>
Daniel Veillard6dbcaf82002-02-20 14:37:47 +00002303 <li>There is another <a href="http://libgdome-cpp.berlios.de/">C++ wrapper
Daniel Veillard0b28e882002-07-24 23:47:05 +00002304 based on the gdome2 bindings</a> maintained by Tobias Peters.</li>
Daniel Veillard9b6fd302002-05-13 12:06:47 +00002305 <li>and a third C++ wrapper by Peter Jones &lt;pjones@pmade.org&gt;
2306 <p>Website: <a
2307 href="http://pmade.org/pjones/software/xmlwrapp/">http://pmade.org/pjones/software/xmlwrapp/</a></p>
2308 </li>
Daniel Veillard6dbcaf82002-02-20 14:37:47 +00002309 <li><a
2310 href="http://mail.gnome.org/archives/xml/2001-March/msg00014.html">Matt
Daniel Veillard63d83142002-05-20 06:51:05 +00002311 Sergeant</a> developed <a
2312 href="http://axkit.org/download/">XML::LibXSLT</a>, a Perl wrapper for
Daniel Veillardaf43f632002-03-08 15:05:20 +00002313 libxml2/libxslt as part of the <a href="http://axkit.com/">AxKit XML
Daniel Veillard0b28e882002-07-24 23:47:05 +00002314 application server</a>.</li>
Daniel Veillard4ac494b2003-09-18 15:08:00 +00002315 <li>If you're interested into scripting XML processing, have a look at <a
2316 href="http://xsh.sourceforge.net/">XSH</a> an XML editing shell based on
2317 Libxml2 Perl bindings.</li>
Daniel Veillard21473672002-06-17 07:29:22 +00002318 <li><a href="mailto:dkuhlman@cutter.rexx.com">Dave Kuhlman</a> provides an
Daniel Veillardaf43f632002-03-08 15:05:20 +00002319 earlier version of the libxml/libxslt <a
Daniel Veillard0b28e882002-07-24 23:47:05 +00002320 href="http://www.rexx.com/~dkuhlman">wrappers for Python</a>.</li>
Daniel Veillard21473672002-06-17 07:29:22 +00002321 <li>Gopal.V and Peter Minten develop <a
2322 href="http://savannah.gnu.org/projects/libxmlsharp">libxml#</a>, a set of
Daniel Veillard0b28e882002-07-24 23:47:05 +00002323 C# libxml2 bindings.</li>
Daniel Veillard6dbcaf82002-02-20 14:37:47 +00002324 <li>Petr Kozelka provides <a
2325 href="http://sourceforge.net/projects/libxml2-pas">Pascal units to glue
Daniel Veillard0b28e882002-07-24 23:47:05 +00002326 libxml2</a> with Kylix, Delphi and other Pascal compilers.</li>
Daniel Veillardb2fb8ed2002-04-01 09:33:12 +00002327 <li>Uwe Fechner also provides <a
2328 href="http://sourceforge.net/projects/idom2-pas/">idom2</a>, a DOM2
Daniel Veillard0b28e882002-07-24 23:47:05 +00002329 implementation for Kylix2/D5/D6 from Borland.</li>
Daniel Veillard6dbcaf82002-02-20 14:37:47 +00002330 <li>Wai-Sun "Squidster" Chia provides <a
2331 href="http://www.rubycolor.org/arc/redist/">bindings for Ruby</a> and
2332 libxml2 bindings are also available in Ruby through the <a
2333 href="http://libgdome-ruby.berlios.de/">libgdome-ruby</a> module
2334 maintained by Tobias Peters.</li>
Daniel Veillardaf43f632002-03-08 15:05:20 +00002335 <li>Steve Ball and contributors maintains <a
2336 href="http://tclxml.sourceforge.net/">libxml2 and libxslt bindings for
Daniel Veillard0b28e882002-07-24 23:47:05 +00002337 Tcl</a>.</li>
Daniel Veillardaf43f632002-03-08 15:05:20 +00002338 <li>There is support for libxml2 in the DOM module of PHP.</li>
Daniel Veillard41b01a82003-02-27 11:09:06 +00002339 <li><a href="http://savannah.gnu.org/projects/classpathx/">LibxmlJ</a> is
Daniel Veillard806cada2003-03-19 21:58:59 +00002340 an effort to create a 100% JAXP-compatible Java wrapper for libxml2 and
2341 libxslt as part of GNU ClasspathX project.</li>
Daniel Veillard6d373a22003-11-04 10:26:43 +00002342 <li>Patrick McPhee provides Rexx bindings fof libxml2 and libxslt, look for
2343 <a href="http://www.interlog.com/~ptjm/software.html">RexxXML</a>.</li>
Daniel Veillardb78757b2004-12-30 21:30:23 +00002344 <li><a href="http://www.satimage.fr/software/en/xml_suite.html">Satimage</a>
2345 provides <a
2346 href="http://www.satimage.fr/software/en/downloads_osaxen.html">XMLLib
2347 osax</a>. This is an osax for Mac OS X with a set of commands to
2348 implement in AppleScript the XML DOM, XPATH and XSLT. Also includes
Daniel Veillardc7426092005-01-05 15:11:41 +00002349 commands for Property-lists (Apple's fast lookup table XML format.)</li>
2350 <li>Francesco Montorsi developped
2351<a href="https://sourceforge.net/project/showfiles.php?group_id=51305&amp;package_id=45182">wxXml2</a>
2352 wrappers that interface libxml2, allowing wxWidgets applications to
2353 load/save/edit XML instances.</li>
Daniel Veillard6dbcaf82002-02-20 14:37:47 +00002354</ul>
2355
Daniel Veillardc0801af2002-05-28 16:28:42 +00002356<p>The distribution includes a set of Python bindings, which are guaranteed
2357to be maintained as part of the library in the future, though the Python
Daniel Veillard41b01a82003-02-27 11:09:06 +00002358interface have not yet reached the completeness of the C API.</p>
Daniel Veillard7b4b2f92003-01-06 13:11:20 +00002359
Daniel Veillard27907c72002-12-16 16:05:58 +00002360<p><a href="mailto:stephane.bidoul@softwareag.com">Stéphane Bidoul</a>
Daniel Veillard7b4b2f92003-01-06 13:11:20 +00002361maintains <a href="http://users.skynet.be/sbi/libxml-python/">a Windows port
2362of the Python bindings</a>.</p>
Daniel Veillardaf43f632002-03-08 15:05:20 +00002363
Daniel Veillard7ef0fcb2002-12-14 10:38:55 +00002364<p>Note to people interested in building bindings, the API is formalized as
2365<a href="libxml2-api.xml">an XML API description file</a> which allows to
2366automate a large part of the Python bindings, this includes function
Daniel Veillard7b4b2f92003-01-06 13:11:20 +00002367descriptions, enums, structures, typedefs, etc... The Python script used to
2368build the bindings is python/generator.py in the source distribution.</p>
Daniel Veillard7ef0fcb2002-12-14 10:38:55 +00002369
Daniel Veillardaf43f632002-03-08 15:05:20 +00002370<p>To install the Python bindings there are 2 options:</p>
Daniel Veillard0b79dfe2002-02-23 13:02:31 +00002371<ul>
Daniel Veillardaf43f632002-03-08 15:05:20 +00002372 <li>If you use an RPM based distribution, simply install the <a
2373 href="http://rpmfind.net/linux/rpm2html/search.php?query=libxml2-python">libxml2-python
2374 RPM</a> (and if needed the <a
2375 href="http://rpmfind.net/linux/rpm2html/search.php?query=libxslt-python">libxslt-python
2376 RPM</a>).</li>
2377 <li>Otherwise use the <a href="ftp://xmlsoft.org/python/">libxml2-python
2378 module distribution</a> corresponding to your installed version of
2379 libxml2 and libxslt. Note that to install it you will need both libxml2
2380 and libxslt installed and run "python setup.py build install" in the
2381 module tree.</li>
Daniel Veillard0b79dfe2002-02-23 13:02:31 +00002382</ul>
Daniel Veillardaf43f632002-03-08 15:05:20 +00002383
2384<p>The distribution includes a set of examples and regression tests for the
2385python bindings in the <code>python/tests</code> directory. Here are some
Daniel Veillard0b28e882002-07-24 23:47:05 +00002386excerpts from those tests:</p>
Daniel Veillard6dbcaf82002-02-20 14:37:47 +00002387
2388<h3>tst.py:</h3>
2389
2390<p>This is a basic test of the file interface and DOM navigation:</p>
MST 2003 John Fleck2dffb762003-11-29 04:41:24 +00002391<pre>import libxml2, sys
Daniel Veillard6dbcaf82002-02-20 14:37:47 +00002392
2393doc = libxml2.parseFile("tst.xml")
2394if doc.name != "tst.xml":
2395 print "doc.name failed"
2396 sys.exit(1)
2397root = doc.children
2398if root.name != "doc":
2399 print "root.name failed"
2400 sys.exit(1)
2401child = root.children
2402if child.name != "foo":
2403 print "child.name failed"
2404 sys.exit(1)
2405doc.freeDoc()</pre>
2406
Daniel Veillard0b28e882002-07-24 23:47:05 +00002407<p>The Python module is called libxml2; parseFile is the equivalent of
Daniel Veillard6dbcaf82002-02-20 14:37:47 +00002408xmlParseFile (most of the bindings are automatically generated, and the xml
2409prefix is removed and the casing convention are kept). All node seen at the
Daniel Veillard63d83142002-05-20 06:51:05 +00002410binding level share the same subset of accessors:</p>
Daniel Veillard6dbcaf82002-02-20 14:37:47 +00002411<ul>
Daniel Veillardaf43f632002-03-08 15:05:20 +00002412 <li><code>name</code> : returns the node name</li>
Daniel Veillardc0801af2002-05-28 16:28:42 +00002413 <li><code>type</code> : returns a string indicating the node type</li>
Daniel Veillardaf43f632002-03-08 15:05:20 +00002414 <li><code>content</code> : returns the content of the node, it is based on
2415 xmlNodeGetContent() and hence is recursive.</li>
2416 <li><code>parent</code> , <code>children</code>, <code>last</code>,
2417 <code>next</code>, <code>prev</code>, <code>doc</code>,
2418 <code>properties</code>: pointing to the associated element in the tree,
2419 those may return None in case no such link exists.</li>
Daniel Veillard6dbcaf82002-02-20 14:37:47 +00002420</ul>
2421
Daniel Veillard63d83142002-05-20 06:51:05 +00002422<p>Also note the need to explicitly deallocate documents with freeDoc() .
Daniel Veillard6dbcaf82002-02-20 14:37:47 +00002423Reference counting for libxml2 trees would need quite a lot of work to
2424function properly, and rather than risk memory leaks if not implemented
2425correctly it sounds safer to have an explicit function to free a tree. The
2426wrapper python objects like doc, root or child are them automatically garbage
2427collected.</p>
2428
2429<h3>validate.py:</h3>
2430
2431<p>This test check the validation interfaces and redirection of error
2432messages:</p>
2433<pre>import libxml2
2434
Daniel Veillard63d83142002-05-20 06:51:05 +00002435#deactivate error messages from the validation
Daniel Veillard6dbcaf82002-02-20 14:37:47 +00002436def noerr(ctx, str):
2437 pass
2438
2439libxml2.registerErrorHandler(noerr, None)
2440
2441ctxt = libxml2.createFileParserCtxt("invalid.xml")
2442ctxt.validate(1)
2443ctxt.parseDocument()
2444doc = ctxt.doc()
2445valid = ctxt.isValid()
2446doc.freeDoc()
2447if valid != 0:
Daniel Veillard63d83142002-05-20 06:51:05 +00002448 print "validity check failed"</pre>
Daniel Veillard6dbcaf82002-02-20 14:37:47 +00002449
2450<p>The first thing to notice is the call to registerErrorHandler(), it
2451defines a new error handler global to the library. It is used to avoid seeing
2452the error messages when trying to validate the invalid document.</p>
2453
2454<p>The main interest of that test is the creation of a parser context with
2455createFileParserCtxt() and how the behaviour can be changed before calling
Daniel Veillard63d83142002-05-20 06:51:05 +00002456parseDocument() . Similarly the informations resulting from the parsing phase
Daniel Veillard6dbcaf82002-02-20 14:37:47 +00002457are also available using context methods.</p>
2458
2459<p>Contexts like nodes are defined as class and the libxml2 wrappers maps the
2460C function interfaces in terms of objects method as much as possible. The
2461best to get a complete view of what methods are supported is to look at the
2462libxml2.py module containing all the wrappers.</p>
2463
2464<h3>push.py:</h3>
2465
2466<p>This test show how to activate the push parser interface:</p>
2467<pre>import libxml2
2468
2469ctxt = libxml2.createPushParser(None, "&lt;foo", 4, "test.xml")
2470ctxt.parseChunk("/&gt;", 2, 1)
2471doc = ctxt.doc()
2472
2473doc.freeDoc()</pre>
2474
Daniel Veillard63d83142002-05-20 06:51:05 +00002475<p>The context is created with a special call based on the
Daniel Veillard6dbcaf82002-02-20 14:37:47 +00002476xmlCreatePushParser() from the C library. The first argument is an optional
Daniel Veillard63d83142002-05-20 06:51:05 +00002477SAX callback object, then the initial set of data, the length and the name of
Daniel Veillard6dbcaf82002-02-20 14:37:47 +00002478the resource in case URI-References need to be computed by the parser.</p>
2479
2480<p>Then the data are pushed using the parseChunk() method, the last call
Daniel Veillard63d83142002-05-20 06:51:05 +00002481setting the third argument terminate to 1.</p>
Daniel Veillard6dbcaf82002-02-20 14:37:47 +00002482
2483<h3>pushSAX.py:</h3>
2484
2485<p>this test show the use of the event based parsing interfaces. In this case
2486the parser does not build a document, but provides callback information as
2487the parser makes progresses analyzing the data being provided:</p>
2488<pre>import libxml2
2489log = ""
2490
2491class callback:
2492 def startDocument(self):
2493 global log
2494 log = log + "startDocument:"
2495
2496 def endDocument(self):
2497 global log
2498 log = log + "endDocument:"
2499
2500 def startElement(self, tag, attrs):
2501 global log
2502 log = log + "startElement %s %s:" % (tag, attrs)
2503
2504 def endElement(self, tag):
2505 global log
2506 log = log + "endElement %s:" % (tag)
2507
2508 def characters(self, data):
2509 global log
2510 log = log + "characters: %s:" % (data)
2511
2512 def warning(self, msg):
2513 global log
2514 log = log + "warning: %s:" % (msg)
2515
2516 def error(self, msg):
2517 global log
2518 log = log + "error: %s:" % (msg)
2519
2520 def fatalError(self, msg):
2521 global log
2522 log = log + "fatalError: %s:" % (msg)
2523
2524handler = callback()
2525
2526ctxt = libxml2.createPushParser(handler, "&lt;foo", 4, "test.xml")
2527chunk = " url='tst'&gt;b"
2528ctxt.parseChunk(chunk, len(chunk), 0)
2529chunk = "ar&lt;/foo&gt;"
2530ctxt.parseChunk(chunk, len(chunk), 1)
2531
Daniel Veillardfcbfa2d2002-02-21 17:54:27 +00002532reference = "startDocument:startElement foo {'url': 'tst'}:" + \
2533 "characters: bar:endElement foo:endDocument:"
Daniel Veillard6dbcaf82002-02-20 14:37:47 +00002534if log != reference:
2535 print "Error got: %s" % log
Daniel Veillard63d83142002-05-20 06:51:05 +00002536 print "Expected: %s" % reference</pre>
Daniel Veillard6dbcaf82002-02-20 14:37:47 +00002537
2538<p>The key object in that test is the handler, it provides a number of entry
2539points which can be called by the parser as it makes progresses to indicate
2540the information set obtained. The full set of callback is larger than what
2541the callback class in that specific example implements (see the SAX
2542definition for a complete list). The wrapper will only call those supplied by
2543the object when activated. The startElement receives the names of the element
Daniel Veillard63d83142002-05-20 06:51:05 +00002544and a dictionary containing the attributes carried by this element.</p>
Daniel Veillard6dbcaf82002-02-20 14:37:47 +00002545
2546<p>Also note that the reference string generated from the callback shows a
2547single character call even though the string "bar" is passed to the parser
2548from 2 different call to parseChunk()</p>
2549
2550<h3>xpath.py:</h3>
2551
Daniel Veillard63d83142002-05-20 06:51:05 +00002552<p>This is a basic test of XPath wrappers support</p>
Daniel Veillard6dbcaf82002-02-20 14:37:47 +00002553<pre>import libxml2
2554
2555doc = libxml2.parseFile("tst.xml")
2556ctxt = doc.xpathNewContext()
2557res = ctxt.xpathEval("//*")
2558if len(res) != 2:
2559 print "xpath query: wrong node set size"
2560 sys.exit(1)
2561if res[0].name != "doc" or res[1].name != "foo":
2562 print "xpath query: wrong node set value"
2563 sys.exit(1)
2564doc.freeDoc()
2565ctxt.xpathFreeContext()</pre>
2566
2567<p>This test parses a file, then create an XPath context to evaluate XPath
2568expression on it. The xpathEval() method execute an XPath query and returns
2569the result mapped in a Python way. String and numbers are natively converted,
2570and node sets are returned as a tuple of libxml2 Python nodes wrappers. Like
Daniel Veillard63d83142002-05-20 06:51:05 +00002571the document, the XPath context need to be freed explicitly, also not that
Daniel Veillard6dbcaf82002-02-20 14:37:47 +00002572the result of the XPath query may point back to the document tree and hence
2573the document must be freed after the result of the query is used.</p>
2574
2575<h3>xpathext.py:</h3>
2576
2577<p>This test shows how to extend the XPath engine with functions written in
2578python:</p>
2579<pre>import libxml2
2580
2581def foo(ctx, x):
2582 return x + 1
2583
2584doc = libxml2.parseFile("tst.xml")
2585ctxt = doc.xpathNewContext()
2586libxml2.registerXPathFunction(ctxt._o, "foo", None, foo)
2587res = ctxt.xpathEval("foo(1)")
2588if res != 2:
2589 print "xpath extension failure"
2590doc.freeDoc()
2591ctxt.xpathFreeContext()</pre>
2592
2593<p>Note how the extension function is registered with the context (but that
Daniel Veillard63d83142002-05-20 06:51:05 +00002594part is not yet finalized, this may change slightly in the future).</p>
Daniel Veillard6dbcaf82002-02-20 14:37:47 +00002595
2596<h3>tstxpath.py:</h3>
2597
Daniel Veillard63d83142002-05-20 06:51:05 +00002598<p>This test is similar to the previous one but shows how the extension
Daniel Veillard6dbcaf82002-02-20 14:37:47 +00002599function can access the XPath evaluation context:</p>
2600<pre>def foo(ctx, x):
2601 global called
2602
2603 #
2604 # test that access to the XPath evaluation contexts
2605 #
2606 pctxt = libxml2.xpathParserContext(_obj=ctx)
2607 ctxt = pctxt.context()
2608 called = ctxt.function()
2609 return x + 1</pre>
2610
2611<p>All the interfaces around the XPath parser(or rather evaluation) context
2612are not finalized, but it should be sufficient to do contextual work at the
2613evaluation point.</p>
2614
2615<h3>Memory debugging:</h3>
2616
2617<p>last but not least, all tests starts with the following prologue:</p>
2618<pre>#memory debug specific
Daniel Veillardaf43f632002-03-08 15:05:20 +00002619libxml2.debugMemory(1)</pre>
Daniel Veillard6dbcaf82002-02-20 14:37:47 +00002620
2621<p>and ends with the following epilogue:</p>
2622<pre>#memory debug specific
2623libxml2.cleanupParser()
2624if libxml2.debugMemory(1) == 0:
2625 print "OK"
2626else:
2627 print "Memory leak %d bytes" % (libxml2.debugMemory(1))
2628 libxml2.dumpMemory()</pre>
2629
2630<p>Those activate the memory debugging interface of libxml2 where all
Daniel Veillard63d83142002-05-20 06:51:05 +00002631allocated block in the library are tracked. The prologue then cleans up the
Daniel Veillard6dbcaf82002-02-20 14:37:47 +00002632library state and checks that all allocated memory has been freed. If not it
2633calls dumpMemory() which saves that list in a <code>.memdump</code> file.</p>
Daniel Veillard82687162001-01-22 15:32:01 +00002634
Daniel Veillard8a469172003-06-12 16:05:07 +00002635<h2><a name="architecture">libxml2 architecture</a></h2>
Daniel Veillard4540be42000-08-19 16:40:28 +00002636
Daniel Veillard560c2a42003-07-06 21:13:49 +00002637<p>Libxml2 is made of multiple components; some of them are optional, and
2638most of the block interfaces are public. The main components are:</p>
Daniel Veillard4540be42000-08-19 16:40:28 +00002639<ul>
2640 <li>an Input/Output layer</li>
Daniel Veillard91e9d582001-02-26 07:31:12 +00002641 <li>FTP and HTTP client layers (optional)</li>
Daniel Veillard4540be42000-08-19 16:40:28 +00002642 <li>an Internationalization layer managing the encodings support</li>
Daniel Veillard91e9d582001-02-26 07:31:12 +00002643 <li>a URI module</li>
Daniel Veillard4540be42000-08-19 16:40:28 +00002644 <li>the XML parser and its basic SAX interface</li>
Daniel Veillard91e9d582001-02-26 07:31:12 +00002645 <li>an HTML parser using the same SAX interface (optional)</li>
Daniel Veillard4540be42000-08-19 16:40:28 +00002646 <li>a SAX tree module to build an in-memory DOM representation</li>
2647 <li>a tree module to manipulate the DOM representation</li>
Daniel Veillard91e9d582001-02-26 07:31:12 +00002648 <li>a validation module using the DOM representation (optional)</li>
Daniel Veillard4540be42000-08-19 16:40:28 +00002649 <li>an XPath module for global lookup in a DOM representation
Daniel Veillard91e9d582001-02-26 07:31:12 +00002650 (optional)</li>
2651 <li>a debug module (optional)</li>
Daniel Veillard4540be42000-08-19 16:40:28 +00002652</ul>
2653
2654<p>Graphically this gives the following:</p>
2655
2656<p><img src="libxml.gif" alt="a graphical view of the various"></p>
2657
2658<p></p>
2659
Daniel Veillard2f4dfc41999-09-24 14:03:48 +00002660<h2><a name="tree">The tree output</a></h2>
Daniel Veillardb05deb71999-08-10 19:04:08 +00002661
2662<p>The parser returns a tree built during the document analysis. The value
Daniel Veillard402e8c82000-02-29 22:57:47 +00002663returned is an <strong>xmlDocPtr</strong> (i.e., a pointer to an
Daniel Veillardf13e1ed2000-03-06 07:41:49 +00002664<strong>xmlDoc</strong> structure). This structure contains information such
Daniel Veillard306be992000-07-03 12:38:45 +00002665as the file name, the document type, and a <strong>children</strong> pointer
2666which is the root of the document (or more exactly the first child under the
2667root which is the document). The tree is made of <strong>xmlNode</strong>s,
Daniel Veillard91e9d582001-02-26 07:31:12 +00002668chained in double-linked lists of siblings and with a children&lt;-&gt;parent
Daniel Veillard306be992000-07-03 12:38:45 +00002669relationship. An xmlNode can also carry properties (a chain of xmlAttr
2670structures). An attribute may have a value which is a list of TEXT or
2671ENTITY_REF nodes.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +00002672
Daniel Veillard88f00ae2000-03-02 00:15:55 +00002673<p>Here is an example (erroneous with respect to the XML spec since there
2674should be only one ELEMENT under the root):</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +00002675
2676<p><img src="structure.gif" alt=" structure.gif "></p>
2677
2678<p>In the source package there is a small program (not installed by default)
Daniel Veillard361d8452000-04-03 19:48:13 +00002679called <strong>xmllint</strong> which parses XML files given as argument and
Daniel Veillardf13e1ed2000-03-06 07:41:49 +00002680prints them back as parsed. This is useful for detecting errors both in XML
2681code and in the XML parser itself. It has an option <strong>--debug</strong>
Daniel Veillard91e9d582001-02-26 07:31:12 +00002682which prints the actual in-memory structure of the document; here is the
Daniel Veillardf13e1ed2000-03-06 07:41:49 +00002683result with the <a href="#example">example</a> given before:</p>
Daniel Veillard10c6a8f1998-10-28 01:00:12 +00002684<pre>DOCUMENT
2685version=1.0
2686standalone=true
2687 ELEMENT EXAMPLE
2688 ATTRIBUTE prop1
2689 TEXT
2690 content=gnome is great
2691 ATTRIBUTE prop2
2692 ENTITY_REF
2693 TEXT
Daniel Veillard0142b842000-01-14 14:45:24 +00002694 content= linux too
Daniel Veillard402e8c82000-02-29 22:57:47 +00002695 ELEMENT head
Daniel Veillard10c6a8f1998-10-28 01:00:12 +00002696 ELEMENT title
Daniel Veillard25940b71998-10-29 05:51:30 +00002697 TEXT
2698 content=Welcome to Gnome
Daniel Veillard10c6a8f1998-10-28 01:00:12 +00002699 ELEMENT chapter
2700 ELEMENT title
Daniel Veillard25940b71998-10-29 05:51:30 +00002701 TEXT
2702 content=The Linux adventure
Daniel Veillard10c6a8f1998-10-28 01:00:12 +00002703 ELEMENT p
Daniel Veillard25940b71998-10-29 05:51:30 +00002704 TEXT
2705 content=bla bla bla ...
Daniel Veillard10c6a8f1998-10-28 01:00:12 +00002706 ELEMENT image
2707 ATTRIBUTE href
2708 TEXT
2709 content=linus.gif
2710 ELEMENT p
Daniel Veillard25940b71998-10-29 05:51:30 +00002711 TEXT
2712 content=...</pre>
Daniel Veillardb05deb71999-08-10 19:04:08 +00002713
Daniel Veillard88f00ae2000-03-02 00:15:55 +00002714<p>This should be useful for learning the internal representation model.</p>
Daniel Veillardccb09631998-10-27 06:21:04 +00002715
Daniel Veillard2f4dfc41999-09-24 14:03:48 +00002716<h2><a name="interface">The SAX interface</a></h2>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +00002717
Daniel Veillard402e8c82000-02-29 22:57:47 +00002718<p>Sometimes the DOM tree output is just too large to fit reasonably into
Daniel Veillard88f00ae2000-03-02 00:15:55 +00002719memory. In that case (and if you don't expect to save back the XML document
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +00002720loaded using libxml), it's better to use the SAX interface of libxml. SAX is
2721a <strong>callback-based interface</strong> to the parser. Before parsing,
2722the application layer registers a customized set of callbacks which are
2723called by the library as it progresses through the XML input.</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +00002724
Daniel Veillard88f00ae2000-03-02 00:15:55 +00002725<p>To get more detailed step-by-step guidance on using the SAX interface of
Daniel Veillard4540be42000-08-19 16:40:28 +00002726libxml, see the <a
2727href="http://www.daa.com.au/~james/gnome/xml-sax/xml-sax.html">nice
2728documentation</a>.written by <a href="mailto:james@daa.com.au">James
Daniel Veillard88f00ae2000-03-02 00:15:55 +00002729Henstridge</a>.</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +00002730
2731<p>You can debug the SAX behaviour by using the <strong>testSAX</strong>
2732program located in the gnome-xml module (it's usually not shipped in the
Daniel Veillard88f00ae2000-03-02 00:15:55 +00002733binary packages of libxml, but you can find it in the tar source
Daniel Veillard402e8c82000-02-29 22:57:47 +00002734distribution). Here is the sequence of callbacks that would be reported by
Daniel Veillard88f00ae2000-03-02 00:15:55 +00002735testSAX when parsing the example XML document shown earlier:</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +00002736<pre>SAX.setDocumentLocator()
2737SAX.startDocument()
2738SAX.getEntity(amp)
2739SAX.startElement(EXAMPLE, prop1='gnome is great', prop2='&amp;amp; linux too')
2740SAX.characters( , 3)
2741SAX.startElement(head)
2742SAX.characters( , 4)
2743SAX.startElement(title)
2744SAX.characters(Welcome to Gnome, 16)
2745SAX.endElement(title)
2746SAX.characters( , 3)
2747SAX.endElement(head)
2748SAX.characters( , 3)
2749SAX.startElement(chapter)
2750SAX.characters( , 4)
2751SAX.startElement(title)
2752SAX.characters(The Linux adventure, 19)
2753SAX.endElement(title)
2754SAX.characters( , 4)
2755SAX.startElement(p)
2756SAX.characters(bla bla bla ..., 15)
2757SAX.endElement(p)
2758SAX.characters( , 4)
2759SAX.startElement(image, href='linus.gif')
2760SAX.endElement(image)
2761SAX.characters( , 4)
2762SAX.startElement(p)
2763SAX.characters(..., 3)
2764SAX.endElement(p)
2765SAX.characters( , 3)
2766SAX.endElement(chapter)
2767SAX.characters( , 1)
2768SAX.endElement(EXAMPLE)
2769SAX.endDocument()</pre>
2770
Daniel Veillard8a469172003-06-12 16:05:07 +00002771<p>Most of the other interfaces of libxml2 are based on the DOM tree-building
Daniel Veillardec70e912001-02-26 20:10:45 +00002772facility, so nearly everything up to the end of this document presupposes the
2773use of the standard DOM tree build. Note that the DOM tree itself is built by
2774a set of registered default callbacks, without internal specific
2775interface.</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +00002776
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00002777<h2><a name="Validation">Validation &amp; DTDs</a></h2>
2778
2779<p>Table of Content:</p>
2780<ol>
2781 <li><a href="#General5">General overview</a></li>
2782 <li><a href="#definition">The definition</a></li>
2783 <li><a href="#Simple">Simple rules</a>
2784 <ol>
Daniel Veillard9c466822001-10-25 12:03:39 +00002785 <li><a href="#reference">How to reference a DTD from a document</a></li>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00002786 <li><a href="#Declaring">Declaring elements</a></li>
2787 <li><a href="#Declaring1">Declaring attributes</a></li>
2788 </ol>
2789 </li>
2790 <li><a href="#Some">Some examples</a></li>
2791 <li><a href="#validate">How to validate</a></li>
2792 <li><a href="#Other">Other resources</a></li>
2793</ol>
2794
2795<h3><a name="General5">General overview</a></h3>
2796
2797<p>Well what is validation and what is a DTD ?</p>
2798
2799<p>DTD is the acronym for Document Type Definition. This is a description of
Daniel Veillard63d83142002-05-20 06:51:05 +00002800the content for a family of XML files. This is part of the XML 1.0
Daniel Veillard0b28e882002-07-24 23:47:05 +00002801specification, and allows one to describe and verify that a given document
2802instance conforms to the set of rules detailing its structure and content.</p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00002803
2804<p>Validation is the process of checking a document against a DTD (more
2805generally against a set of construction rules).</p>
2806
2807<p>The validation process and building DTDs are the two most difficult parts
Daniel Veillard0b28e882002-07-24 23:47:05 +00002808of the XML life cycle. Briefly a DTD defines all the possible elements to be
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00002809found within your document, what is the formal shape of your document tree
Daniel Veillard0b28e882002-07-24 23:47:05 +00002810(by defining the allowed content of an element; either text, a regular
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00002811expression for the allowed list of children, or mixed content i.e. both text
Daniel Veillard42766c02002-08-22 20:52:17 +00002812and children). The DTD also defines the valid attributes for all elements and
2813the types of those attributes.</p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00002814
2815<h3><a name="definition1">The definition</a></h3>
2816
2817<p>The <a href="http://www.w3.org/TR/REC-xml">W3C XML Recommendation</a> (<a
2818href="http://www.xml.com/axml/axml.html">Tim Bray's annotated version of
2819Rev1</a>):</p>
2820<ul>
2821 <li><a href="http://www.w3.org/TR/REC-xml#elemdecls">Declaring
2822 elements</a></li>
2823 <li><a href="http://www.w3.org/TR/REC-xml#attdecls">Declaring
2824 attributes</a></li>
2825</ul>
2826
2827<p>(unfortunately) all this is inherited from the SGML world, the syntax is
2828ancient...</p>
2829
2830<h3><a name="Simple1">Simple rules</a></h3>
2831
Daniel Veillard42766c02002-08-22 20:52:17 +00002832<p>Writing DTDs can be done in many ways. The rules to build them if you need
2833something permanent or something which can evolve over time can be radically
2834different. Really complex DTDs like DocBook ones are flexible but quite
2835harder to design. I will just focus on DTDs for a formats with a fixed simple
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00002836structure. It is just a set of basic rules, and definitely not exhaustive nor
Daniel Veillard63d83142002-05-20 06:51:05 +00002837usable for complex DTD design.</p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00002838
2839<h4><a name="reference1">How to reference a DTD from a document</a>:</h4>
2840
2841<p>Assuming the top element of the document is <code>spec</code> and the dtd
2842is placed in the file <code>mydtd</code> in the subdirectory
2843<code>dtds</code> of the directory from where the document were loaded:</p>
2844
2845<p><code>&lt;!DOCTYPE spec SYSTEM "dtds/mydtd"&gt;</code></p>
2846
2847<p>Notes:</p>
2848<ul>
Daniel Veillard0b28e882002-07-24 23:47:05 +00002849 <li>The system string is actually an URI-Reference (as defined in <a
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00002850 href="http://www.ietf.org/rfc/rfc2396.txt">RFC 2396</a>) so you can use a
Daniel Veillard0b28e882002-07-24 23:47:05 +00002851 full URL string indicating the location of your DTD on the Web. This is a
2852 really good thing to do if you want others to validate your document.</li>
2853 <li>It is also possible to associate a <code>PUBLIC</code> identifier (a
Daniel Veillard63d83142002-05-20 06:51:05 +00002854 magic string) so that the DTD is looked up in catalogs on the client side
Daniel Veillard0b28e882002-07-24 23:47:05 +00002855 without having to locate it on the web.</li>
2856 <li>A DTD contains a set of element and attribute declarations, but they
Daniel Veillard63d83142002-05-20 06:51:05 +00002857 don't define what the root of the document should be. This is explicitly
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00002858 told to the parser/validator as the first element of the
2859 <code>DOCTYPE</code> declaration.</li>
2860</ul>
2861
2862<h4><a name="Declaring2">Declaring elements</a>:</h4>
2863
2864<p>The following declares an element <code>spec</code>:</p>
2865
2866<p><code>&lt;!ELEMENT spec (front, body, back?)&gt;</code></p>
2867
Daniel Veillard0b28e882002-07-24 23:47:05 +00002868<p>It also expresses that the spec element contains one <code>front</code>,
Daniel Veillardc0801af2002-05-28 16:28:42 +00002869one <code>body</code> and one optional <code>back</code> children elements in
2870this order. The declaration of one element of the structure and its content
2871are done in a single declaration. Similarly the following declares
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00002872<code>div1</code> elements:</p>
2873
Daniel Veillard51737272002-01-23 23:10:38 +00002874<p><code>&lt;!ELEMENT div1 (head, (p | list | note)*, div2?)&gt;</code></p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00002875
Daniel Veillard0b28e882002-07-24 23:47:05 +00002876<p>which means div1 contains one <code>head</code> then a series of optional
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00002877<code>p</code>, <code>list</code>s and <code>note</code>s and then an
2878optional <code>div2</code>. And last but not least an element can contain
2879text:</p>
2880
2881<p><code>&lt;!ELEMENT b (#PCDATA)&gt;</code></p>
2882
2883<p><code>b</code> contains text or being of mixed content (text and elements
2884in no particular order):</p>
2885
2886<p><code>&lt;!ELEMENT p (#PCDATA|a|ul|b|i|em)*&gt;</code></p>
2887
2888<p><code>p </code>can contain text or <code>a</code>, <code>ul</code>,
2889<code>b</code>, <code>i </code>or <code>em</code> elements in no particular
2890order.</p>
2891
2892<h4><a name="Declaring1">Declaring attributes</a>:</h4>
2893
Daniel Veillard0b28e882002-07-24 23:47:05 +00002894<p>Again the attributes declaration includes their content definition:</p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00002895
2896<p><code>&lt;!ATTLIST termdef name CDATA #IMPLIED&gt;</code></p>
2897
2898<p>means that the element <code>termdef</code> can have a <code>name</code>
Daniel Veillard63d83142002-05-20 06:51:05 +00002899attribute containing text (<code>CDATA</code>) and which is optional
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00002900(<code>#IMPLIED</code>). The attribute value can also be defined within a
2901set:</p>
2902
2903<p><code>&lt;!ATTLIST list type (bullets|ordered|glossary)
2904"ordered"&gt;</code></p>
2905
2906<p>means <code>list</code> element have a <code>type</code> attribute with 3
2907allowed values "bullets", "ordered" or "glossary" and which default to
Daniel Veillard63d83142002-05-20 06:51:05 +00002908"ordered" if the attribute is not explicitly specified.</p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00002909
2910<p>The content type of an attribute can be text (<code>CDATA</code>),
2911anchor/reference/references
2912(<code>ID</code>/<code>IDREF</code>/<code>IDREFS</code>), entity(ies)
2913(<code>ENTITY</code>/<code>ENTITIES</code>) or name(s)
2914(<code>NMTOKEN</code>/<code>NMTOKENS</code>). The following defines that a
2915<code>chapter</code> element can have an optional <code>id</code> attribute
2916of type <code>ID</code>, usable for reference from attribute of type
2917IDREF:</p>
2918
2919<p><code>&lt;!ATTLIST chapter id ID #IMPLIED&gt;</code></p>
2920
2921<p>The last value of an attribute definition can be <code>#REQUIRED
2922</code>meaning that the attribute has to be given, <code>#IMPLIED</code>
2923meaning that it is optional, or the default value (possibly prefixed by
2924<code>#FIXED</code> if it is the only allowed).</p>
2925
2926<p>Notes:</p>
2927<ul>
Daniel Veillard0b28e882002-07-24 23:47:05 +00002928 <li>Usually the attributes pertaining to a given element are declared in a
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00002929 single expression, but it is just a convention adopted by a lot of DTD
2930 writers:
2931 <pre>&lt;!ATTLIST termdef
2932 id ID #REQUIRED
2933 name CDATA #IMPLIED&gt;</pre>
2934 <p>The previous construct defines both <code>id</code> and
Daniel Veillard0b28e882002-07-24 23:47:05 +00002935 <code>name</code> attributes for the element <code>termdef</code>.</p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00002936 </li>
2937</ul>
2938
2939<h3><a name="Some1">Some examples</a></h3>
2940
Daniel Veillard8a469172003-06-12 16:05:07 +00002941<p>The directory <code>test/valid/dtds/</code> in the libxml2 distribution
Daniel Veillard42766c02002-08-22 20:52:17 +00002942contains some complex DTD examples. The example in the file
2943<code>test/valid/dia.xml</code> shows an XML file where the simple DTD is
2944directly included within the document.</p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00002945
2946<h3><a name="validate1">How to validate</a></h3>
2947
Daniel Veillard0b28e882002-07-24 23:47:05 +00002948<p>The simplest way is to use the xmllint program included with libxml. The
2949<code>--valid</code> option turns-on validation of the files given as input.
2950For example the following validates a copy of the first revision of the XML
Daniel Veillardb8cfbd12001-10-25 10:53:28 +000029511.0 specification:</p>
2952
2953<p><code>xmllint --valid --noout test/valid/REC-xml-19980210.xml</code></p>
2954
Daniel Veillard0b28e882002-07-24 23:47:05 +00002955<p>the -- noout is used to disable output of the resulting tree.</p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00002956
Daniel Veillard42766c02002-08-22 20:52:17 +00002957<p>The <code>--dtdvalid dtd</code> allows validation of the document(s)
2958against a given DTD.</p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00002959
Daniel Veillard8a469172003-06-12 16:05:07 +00002960<p>Libxml2 exports an API to handle DTDs and validation, check the <a
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00002961href="http://xmlsoft.org/html/libxml-valid.html">associated
2962description</a>.</p>
2963
2964<h3><a name="Other1">Other resources</a></h3>
2965
2966<p>DTDs are as old as SGML. So there may be a number of examples on-line, I
2967will just list one for now, others pointers welcome:</p>
2968<ul>
2969 <li><a href="http://www.xml101.com:8081/dtd/">XML-101 DTD</a></li>
2970</ul>
2971
2972<p>I suggest looking at the examples found under test/valid/dtd and any of
2973the large number of books available on XML. The dia example in test/valid
2974should be both simple and complete enough to allow you to build your own.</p>
2975
2976<p></p>
2977
2978<h2><a name="Memory">Memory Management</a></h2>
2979
2980<p>Table of Content:</p>
2981<ol>
2982 <li><a href="#General3">General overview</a></li>
Daniel Veillard8a469172003-06-12 16:05:07 +00002983 <li><a href="#setting">Setting libxml2 set of memory routines</a></li>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00002984 <li><a href="#cleanup">Cleaning up after parsing</a></li>
2985 <li><a href="#Debugging">Debugging routines</a></li>
2986 <li><a href="#General4">General memory requirements</a></li>
2987</ol>
2988
2989<h3><a name="General3">General overview</a></h3>
2990
2991<p>The module <code><a
2992href="http://xmlsoft.org/html/libxml-xmlmemory.html">xmlmemory.h</a></code>
Daniel Veillard8a469172003-06-12 16:05:07 +00002993provides the interfaces to the libxml2 memory system:</p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00002994<ul>
Daniel Veillard8a469172003-06-12 16:05:07 +00002995 <li>libxml2 does not use the libc memory allocator directly but xmlFree(),
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00002996 xmlMalloc() and xmlRealloc()</li>
2997 <li>those routines can be reallocated to a specific set of routine, by
2998 default the libc ones i.e. free(), malloc() and realloc()</li>
2999 <li>the xmlmemory.c module includes a set of debugging routine</li>
3000</ul>
3001
Daniel Veillard8a469172003-06-12 16:05:07 +00003002<h3><a name="setting">Setting libxml2 set of memory routines</a></h3>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00003003
3004<p>It is sometimes useful to not use the default memory allocator, either for
3005debugging, analysis or to implement a specific behaviour on memory management
3006(like on embedded systems). Two function calls are available to do so:</p>
3007<ul>
Daniel Veillardaf43f632002-03-08 15:05:20 +00003008 <li><a href="http://xmlsoft.org/html/libxml-xmlmemory.html">xmlMemGet
3009 ()</a> which return the current set of functions in use by the parser</li>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00003010 <li><a
3011 href="http://xmlsoft.org/html/libxml-xmlmemory.html">xmlMemSetup()</a>
Daniel Veillardaf43f632002-03-08 15:05:20 +00003012 which allow to set up a new set of memory allocation functions</li>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00003013</ul>
3014
3015<p>Of course a call to xmlMemSetup() should probably be done before calling
Daniel Veillard8a469172003-06-12 16:05:07 +00003016any other libxml2 routines (unless you are sure your allocations routines are
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00003017compatibles).</p>
3018
3019<h3><a name="cleanup">Cleaning up after parsing</a></h3>
3020
Daniel Veillard8a469172003-06-12 16:05:07 +00003021<p>Libxml2 is not stateless, there is a few set of memory structures needing
Daniel Veillard63d83142002-05-20 06:51:05 +00003022allocation before the parser is fully functional (some encoding structures
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00003023for example). This also mean that once parsing is finished there is a tiny
3024amount of memory (a few hundred bytes) which can be recollected if you don't
3025reuse the parser immediately:</p>
3026<ul>
3027 <li><a href="http://xmlsoft.org/html/libxml-parser.html">xmlCleanupParser
Daniel Veillardaf43f632002-03-08 15:05:20 +00003028 ()</a> is a centralized routine to free the parsing states. Note that it
3029 won't deallocate any produced tree if any (use the xmlFreeDoc() and
3030 related routines for this).</li>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00003031 <li><a href="http://xmlsoft.org/html/libxml-parser.html">xmlInitParser
Daniel Veillardaf43f632002-03-08 15:05:20 +00003032 ()</a> is the dual routine allowing to preallocate the parsing state
3033 which can be useful for example to avoid initialization reentrancy
Daniel Veillard8a469172003-06-12 16:05:07 +00003034 problems when using libxml2 in multithreaded applications</li>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00003035</ul>
3036
3037<p>Generally xmlCleanupParser() is safe, if needed the state will be rebuild
3038at the next invocation of parser routines, but be careful of the consequences
3039in multithreaded applications.</p>
3040
3041<h3><a name="Debugging">Debugging routines</a></h3>
3042
Daniel Veillard8a469172003-06-12 16:05:07 +00003043<p>When configured using --with-mem-debug flag (off by default), libxml2 uses
Daniel Veillard63d83142002-05-20 06:51:05 +00003044a set of memory allocation debugging routines keeping track of all allocated
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00003045blocks and the location in the code where the routine was called. A couple of
3046other debugging routines allow to dump the memory allocated infos to a file
3047or call a specific routine when a given block number is allocated:</p>
3048<ul>
3049 <li><a
3050 href="http://xmlsoft.org/html/libxml-xmlmemory.html">xmlMallocLoc()</a>
Daniel Veillardaf43f632002-03-08 15:05:20 +00003051 <a
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00003052 href="http://xmlsoft.org/html/libxml-xmlmemory.html">xmlReallocLoc()</a>
3053 and <a
3054 href="http://xmlsoft.org/html/libxml-xmlmemory.html">xmlMemStrdupLoc()</a>
3055 are the memory debugging replacement allocation routines</li>
3056 <li><a href="http://xmlsoft.org/html/libxml-xmlmemory.html">xmlMemoryDump
Daniel Veillardaf43f632002-03-08 15:05:20 +00003057 ()</a> dumps all the informations about the allocated memory block lefts
3058 in the <code>.memdump</code> file</li>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00003059</ul>
3060
Daniel Veillard8a469172003-06-12 16:05:07 +00003061<p>When developing libxml2 memory debug is enabled, the tests programs call
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00003062xmlMemoryDump () and the "make test" regression tests will check for any
3063memory leak during the full regression test sequence, this helps a lot
Daniel Veillard8a469172003-06-12 16:05:07 +00003064ensuring that libxml2 does not leak memory and bullet proof memory
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00003065allocations use (some libc implementations are known to be far too permissive
3066resulting in major portability problems!).</p>
3067
3068<p>If the .memdump reports a leak, it displays the allocation function and
3069also tries to give some informations about the content and structure of the
3070allocated blocks left. This is sufficient in most cases to find the culprit,
Daniel Veillard63d83142002-05-20 06:51:05 +00003071but not always. Assuming the allocation problem is reproducible, it is
3072possible to find more easily:</p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00003073<ol>
3074 <li>write down the block number xxxx not allocated</li>
Daniel Veillard63d83142002-05-20 06:51:05 +00003075 <li>export the environment variable XML_MEM_BREAKPOINT=xxxx , the easiest
Daniel Veillard75794822002-04-11 16:24:32 +00003076 when using GDB is to simply give the command
3077 <p><code>set environment XML_MEM_BREAKPOINT xxxx</code></p>
3078 <p>before running the program.</p>
3079 </li>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00003080 <li>run the program under a debugger and set a breakpoint on
3081 xmlMallocBreakpoint() a specific function called when this precise block
3082 is allocated</li>
3083 <li>when the breakpoint is reached you can then do a fine analysis of the
3084 allocation an step to see the condition resulting in the missing
3085 deallocation.</li>
3086</ol>
3087
Daniel Veillard8a469172003-06-12 16:05:07 +00003088<p>I used to use a commercial tool to debug libxml2 memory problems but after
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00003089noticing that it was not detecting memory leaks that simple mechanism was
Daniel Veillard75794822002-04-11 16:24:32 +00003090used and proved extremely efficient until now. Lately I have also used <a
3091href="http://developer.kde.org/~sewardj/">valgrind</a> with quite some
3092success, it is tied to the i386 architecture since it works by emulating the
3093processor and instruction set, it is slow but extremely efficient, i.e. it
3094spot memory usage errors in a very precise way.</p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00003095
3096<h3><a name="General4">General memory requirements</a></h3>
3097
Daniel Veillard8a469172003-06-12 16:05:07 +00003098<p>How much libxml2 memory require ? It's hard to tell in average it depends
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00003099of a number of things:</p>
3100<ul>
Daniel Veillard63d83142002-05-20 06:51:05 +00003101 <li>the parser itself should work in a fixed amount of memory, except for
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00003102 information maintained about the stacks of names and entities locations.
3103 The I/O and encoding handlers will probably account for a few KBytes.
3104 This is true for both the XML and HTML parser (though the HTML parser
3105 need more state).</li>
3106 <li>If you are generating the DOM tree then memory requirements will grow
Daniel Veillard63d83142002-05-20 06:51:05 +00003107 nearly linear with the size of the data. In general for a balanced
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00003108 textual document the internal memory requirement is about 4 times the
Daniel Veillard63d83142002-05-20 06:51:05 +00003109 size of the UTF8 serialization of this document (example the XML-1.0
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00003110 recommendation is a bit more of 150KBytes and takes 650KBytes of main
3111 memory when parsed). Validation will add a amount of memory required for
3112 maintaining the external Dtd state which should be linear with the
3113 complexity of the content model defined by the Dtd</li>
Daniel Veillardce192eb2003-04-16 15:58:05 +00003114 <li>If you need to work with fixed memory requirements or don't need the
3115 full DOM tree then using the <a href="xmlreader.html">xmlReader
3116 interface</a> is probably the best way to proceed, it still allows to
3117 validate or operate on subset of the tree if needed.</li>
Daniel Veillard8a469172003-06-12 16:05:07 +00003118 <li>If you don't care about the advanced features of libxml2 like
Daniel Veillardce192eb2003-04-16 15:58:05 +00003119 validation, DOM, XPath or XPointer, don't use entities, need to work with
3120 fixed memory requirements, and try to get the fastest parsing possible
3121 then the SAX interface should be used, but it has known restrictions.</li>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00003122</ul>
3123
3124<p></p>
3125
3126<h2><a name="Encodings">Encodings support</a></h2>
3127
Daniel Veillarde5d68de2005-03-10 15:03:40 +00003128<p>If you are not really familiar with Internationalization (usual shortcut
3129is I18N) , Unicode, characters and glyphs, I suggest you read a <a
3130href="http://www.tbray.org/ongoing/When/200x/2003/04/06/Unicode">presentation</a>
3131by Tim Bray on Unicode and why you should care about it.</p>
3132<p>If you don't understand why <b>it does not make sense to have a string
3133without knowing what encoding it uses</b>, then as Joel Spolsky said
3134<a href="http://www.joelonsoftware.com/articles/Unicode.html">please do
3135not write another line of code until you finish reading that article.</a>.
3136It is a prerequisite to understand this page, and avoid a lot of problems
3137with libxml2, XML or text processing in general.</p>
3138
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00003139<p>Table of Content:</p>
3140<ol>
3141 <li><a href="encoding.html#What">What does internationalization support
3142 mean ?</a></li>
3143 <li><a href="encoding.html#internal">The internal encoding, how and
3144 why</a></li>
3145 <li><a href="encoding.html#implemente">How is it implemented ?</a></li>
3146 <li><a href="encoding.html#Default">Default supported encodings</a></li>
3147 <li><a href="encoding.html#extend">How to extend the existing
3148 support</a></li>
3149</ol>
3150
3151<h3><a name="What">What does internationalization support mean ?</a></h3>
3152
3153<p>XML was designed from the start to allow the support of any character set
3154by using Unicode. Any conformant XML parser has to support the UTF-8 and
3155UTF-16 default encodings which can both express the full unicode ranges. UTF8
Daniel Veillard63d83142002-05-20 06:51:05 +00003156is a variable length encoding whose greatest points are to reuse the same
3157encoding for ASCII and to save space for Western encodings, but it is a bit
Daniel Veillardabfca612004-01-07 23:38:02 +00003158more complex to handle in practice. UTF-16 use 2 bytes per character (and
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00003159sometimes combines two pairs), it makes implementation easier, but looks a
3160bit overkill for Western languages encoding. Moreover the XML specification
Daniel Veillard189f46b2004-01-25 21:03:04 +00003161allows the document to be encoded in other encodings at the condition that
3162they are clearly labeled as such. For example the following is a wellformed
3163XML document encoded in ISO-8859-1 and using accentuated letters that we
3164French like for both markup and content:</p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00003165<pre>&lt;?xml version="1.0" encoding="ISO-8859-1"?&gt;
3166&lt;très&gt;là&lt;/très&gt;</pre>
3167
Daniel Veillard8a469172003-06-12 16:05:07 +00003168<p>Having internationalization support in libxml2 means the following:</p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00003169<ul>
3170 <li>the document is properly parsed</li>
3171 <li>informations about it's encoding are saved</li>
3172 <li>it can be modified</li>
3173 <li>it can be saved in its original encoding</li>
Daniel Veillard8a469172003-06-12 16:05:07 +00003174 <li>it can also be saved in another encoding supported by libxml2 (for
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00003175 example straight UTF8 or even an ASCII form)</li>
3176</ul>
3177
Daniel Veillard8a469172003-06-12 16:05:07 +00003178<p>Another very important point is that the whole libxml2 API, with the
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00003179exception of a few routines to read with a specific encoding or save to a
3180specific encoding, is completely agnostic about the original encoding of the
3181document.</p>
3182
Daniel Veillard8a469172003-06-12 16:05:07 +00003183<p>It should be noted too that the HTML parser embedded in libxml2 now obey
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00003184the same rules too, the following document will be (as of 2.2.2) handled in
Daniel Veillard8a469172003-06-12 16:05:07 +00003185an internationalized fashion by libxml2 too:</p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00003186<pre>&lt;!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"
3187 "http://www.w3.org/TR/REC-html40/loose.dtd"&gt;
3188&lt;html lang="fr"&gt;
3189&lt;head&gt;
3190 &lt;META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=ISO-8859-1"&gt;
3191&lt;/head&gt;
3192&lt;body&gt;
3193&lt;p&gt;W3C crée des standards pour le Web.&lt;/body&gt;
3194&lt;/html&gt;</pre>
3195
3196<h3><a name="internal">The internal encoding, how and why</a></h3>
3197
Daniel Veillardabfca612004-01-07 23:38:02 +00003198<p>One of the core decisions was to force all documents to be converted to a
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00003199default internal encoding, and that encoding to be UTF-8, here are the
Daniel Veillardabfca612004-01-07 23:38:02 +00003200rationales for those choices:</p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00003201<ul>
3202 <li>keeping the native encoding in the internal form would force the libxml
3203 users (or the code associated) to be fully aware of the encoding of the
3204 original document, for examples when adding a text node to a document,
3205 the content would have to be provided in the document encoding, i.e. the
3206 client code would have to check it before hand, make sure it's conformant
3207 to the encoding, etc ... Very hard in practice, though in some specific
3208 cases this may make sense.</li>
3209 <li>the second decision was which encoding. From the XML spec only UTF8 and
3210 UTF16 really makes sense as being the two only encodings for which there
Daniel Veillard63d83142002-05-20 06:51:05 +00003211 is mandatory support. UCS-4 (32 bits fixed size encoding) could be
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00003212 considered an intelligent choice too since it's a direct Unicode mapping
3213 support. I selected UTF-8 on the basis of efficiency and compatibility
3214 with surrounding software:
3215 <ul>
3216 <li>UTF-8 while a bit more complex to convert from/to (i.e. slightly
3217 more costly to import and export CPU wise) is also far more compact
3218 than UTF-16 (and UCS-4) for a majority of the documents I see it used
3219 for right now (RPM RDF catalogs, advogato data, various configuration
3220 file formats, etc.) and the key point for today's computer
3221 architecture is efficient uses of caches. If one nearly double the
3222 memory requirement to store the same amount of data, this will trash
3223 caches (main memory/external caches/internal caches) and my take is
3224 that this harms the system far more than the CPU requirements needed
3225 for the conversion to UTF-8</li>
Daniel Veillard8a469172003-06-12 16:05:07 +00003226 <li>Most of libxml2 version 1 users were using it with straight ASCII
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00003227 most of the time, doing the conversion with an internal encoding
3228 requiring all their code to be rewritten was a serious show-stopper
3229 for using UTF-16 or UCS-4.</li>
3230 <li>UTF-8 is being used as the de-facto internal encoding standard for
3231 related code like the <a href="http://www.pango.org/">pango</a>
Daniel Veillardabfca612004-01-07 23:38:02 +00003232 upcoming Gnome text widget, and a lot of Unix code (yet another place
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00003233 where Unix programmer base takes a different approach from Microsoft
3234 - they are using UTF-16)</li>
3235 </ul>
3236 </li>
3237</ul>
3238
Daniel Veillard8a469172003-06-12 16:05:07 +00003239<p>What does this mean in practice for the libxml2 user:</p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00003240<ul>
Daniel Veillard8a469172003-06-12 16:05:07 +00003241 <li>xmlChar, the libxml2 data type is a byte, those bytes must be assembled
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00003242 as UTF-8 valid strings. The proper way to terminate an xmlChar * string
3243 is simply to append 0 byte, as usual.</li>
3244 <li>One just need to make sure that when using chars outside the ASCII set,
3245 the values has been properly converted to UTF-8</li>
3246</ul>
3247
3248<h3><a name="implemente">How is it implemented ?</a></h3>
3249
3250<p>Let's describe how all this works within libxml, basically the I18N
3251(internationalization) support get triggered only during I/O operation, i.e.
3252when reading a document or saving one. Let's look first at the reading
3253sequence:</p>
3254<ol>
3255 <li>when a document is processed, we usually don't know the encoding, a
Daniel Veillard189f46b2004-01-25 21:03:04 +00003256 simple heuristic allows to detect UTF-16 and UCS-4 from encodings where
3257 the ASCII range (0-0x7F) maps with ASCII</li>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00003258 <li>the xml declaration if available is parsed, including the encoding
3259 declaration. At that point, if the autodetected encoding is different
3260 from the one declared a call to xmlSwitchEncoding() is issued.</li>
3261 <li>If there is no encoding declaration, then the input has to be in either
3262 UTF-8 or UTF-16, if it is not then at some point when processing the
3263 input, the converter/checker of UTF-8 form will raise an encoding error.
3264 You may end-up with a garbled document, or no document at all ! Example:
3265 <pre>~/XML -&gt; ./xmllint err.xml
3266err.xml:1: error: Input is not proper UTF-8, indicate encoding !
3267&lt;très&gt;là&lt;/très&gt;
3268 ^
3269err.xml:1: error: Bytes: 0xE8 0x73 0x3E 0x6C
3270&lt;très&gt;là&lt;/très&gt;
3271 ^</pre>
3272 </li>
Daniel Veillard63d83142002-05-20 06:51:05 +00003273 <li>xmlSwitchEncoding() does an encoding name lookup, canonicalize it, and
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00003274 then search the default registered encoding converters for that encoding.
3275 If it's not within the default set and iconv() support has been compiled
3276 it, it will ask iconv for such an encoder. If this fails then the parser
3277 will report an error and stops processing:
3278 <pre>~/XML -&gt; ./xmllint err2.xml
3279err2.xml:1: error: Unsupported encoding UnsupportedEnc
3280&lt;?xml version="1.0" encoding="UnsupportedEnc"?&gt;
3281 ^</pre>
3282 </li>
Daniel Veillard46c5c1d2002-05-20 07:15:54 +00003283 <li>From that point the encoder processes progressively the input (it is
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00003284 plugged as a front-end to the I/O module) for that entity. It captures
Daniel Veillardabfca612004-01-07 23:38:02 +00003285 and converts on-the-fly the document to be parsed to UTF-8. The parser
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00003286 itself just does UTF-8 checking of this input and process it
3287 transparently. The only difference is that the encoding information has
3288 been added to the parsing context (more precisely to the input
3289 corresponding to this entity).</li>
3290 <li>The result (when using DOM) is an internal form completely in UTF-8
3291 with just an encoding information on the document node.</li>
3292</ol>
3293
Daniel Veillard63d83142002-05-20 06:51:05 +00003294<p>Ok then what happens when saving the document (assuming you
3295collected/built an xmlDoc DOM like structure) ? It depends on the function
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00003296called, xmlSaveFile() will just try to save in the original encoding, while
3297xmlSaveFileTo() and xmlSaveFileEnc() can optionally save to a given
3298encoding:</p>
3299<ol>
Daniel Veillard8a469172003-06-12 16:05:07 +00003300 <li>if no encoding is given, libxml2 will look for an encoding value
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00003301 associated to the document and if it exists will try to save to that
3302 encoding,
3303 <p>otherwise everything is written in the internal form, i.e. UTF-8</p>
3304 </li>
3305 <li>so if an encoding was specified, either at the API level or on the
Daniel Veillard8a469172003-06-12 16:05:07 +00003306 document, libxml2 will again canonicalize the encoding name, lookup for a
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00003307 converter in the registered set or through iconv. If not found the
3308 function will return an error code</li>
3309 <li>the converter is placed before the I/O buffer layer, as another kind of
Daniel Veillard8a469172003-06-12 16:05:07 +00003310 buffer, then libxml2 will simply push the UTF-8 serialization to through
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00003311 that buffer, which will then progressively be converted and pushed onto
3312 the I/O layer.</li>
3313 <li>It is possible that the converter code fails on some input, for example
Daniel Veillard63d83142002-05-20 06:51:05 +00003314 trying to push an UTF-8 encoded Chinese character through the UTF-8 to
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00003315 ISO-8859-1 converter won't work. Since the encoders are progressive they
3316 will just report the error and the number of bytes converted, at that
Daniel Veillard8a469172003-06-12 16:05:07 +00003317 point libxml2 will decode the offending character, remove it from the
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00003318 buffer and replace it with the associated charRef encoding &amp;#123; and
Daniel Veillard63d83142002-05-20 06:51:05 +00003319 resume the conversion. This guarantees that any document will be saved
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00003320 without losses (except for markup names where this is not legal, this is
Daniel Veillard63d83142002-05-20 06:51:05 +00003321 a problem in the current version, in practice avoid using non-ascii
Daniel Veillard189f46b2004-01-25 21:03:04 +00003322 characters for tag or attribute names). A special "ascii" encoding name
3323 is used to save documents to a pure ascii form can be used when
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00003324 portability is really crucial</li>
3325</ol>
3326
Daniel Veillardabfca612004-01-07 23:38:02 +00003327<p>Here are a few examples based on the same test document:</p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00003328<pre>~/XML -&gt; ./xmllint isolat1
3329&lt;?xml version="1.0" encoding="ISO-8859-1"?&gt;
3330&lt;très&gt;là&lt;/très&gt;
3331~/XML -&gt; ./xmllint --encode UTF-8 isolat1
3332&lt;?xml version="1.0" encoding="UTF-8"?&gt;
3333&lt;très&gt;là  &lt;/très&gt;
3334~/XML -&gt; </pre>
3335
3336<p>The same processing is applied (and reuse most of the code) for HTML I18N
3337processing. Looking up and modifying the content encoding is a bit more
3338difficult since it is located in a &lt;meta&gt; tag under the &lt;head&gt;,
3339so a couple of functions htmlGetMetaEncoding() and htmlSetMetaEncoding() have
3340been provided. The parser also attempts to switch encoding on the fly when
3341detecting such a tag on input. Except for that the processing is the same
3342(and again reuses the same code).</p>
3343
3344<h3><a name="Default">Default supported encodings</a></h3>
3345
Daniel Veillard8a469172003-06-12 16:05:07 +00003346<p>libxml2 has a set of default converters for the following encodings
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00003347(located in encoding.c):</p>
3348<ol>
3349 <li>UTF-8 is supported by default (null handlers)</li>
3350 <li>UTF-16, both little and big endian</li>
3351 <li>ISO-Latin-1 (ISO-8859-1) covering most western languages</li>
3352 <li>ASCII, useful mostly for saving</li>
3353 <li>HTML, a specific handler for the conversion of UTF-8 to ASCII with HTML
3354 predefined entities like &amp;copy; for the Copyright sign.</li>
3355</ol>
3356
Daniel Veillardc0801af2002-05-28 16:28:42 +00003357<p>More over when compiled on an Unix platform with iconv support the full
3358set of encodings supported by iconv can be instantly be used by libxml. On a
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00003359linux machine with glibc-2.1 the list of supported encodings and aliases fill
33603 full pages, and include UCS-4, the full set of ISO-Latin encodings, and the
3361various Japanese ones.</p>
3362
3363<h4>Encoding aliases</h4>
3364
Daniel Veillard8a469172003-06-12 16:05:07 +00003365<p>From 2.2.3, libxml2 has support to register encoding names aliases. The
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00003366goal is to be able to parse document whose encoding is supported but where
3367the name differs (for example from the default set of names accepted by
3368iconv). The following functions allow to register and handle new aliases for
Daniel Veillard8a469172003-06-12 16:05:07 +00003369existing encodings. Once registered libxml2 will automatically lookup the
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00003370aliases when handling a document:</p>
3371<ul>
3372 <li>int xmlAddEncodingAlias(const char *name, const char *alias);</li>
3373 <li>int xmlDelEncodingAlias(const char *alias);</li>
3374 <li>const char * xmlGetEncodingAlias(const char *alias);</li>
3375 <li>void xmlCleanupEncodingAliases(void);</li>
3376</ul>
3377
3378<h3><a name="extend">How to extend the existing support</a></h3>
3379
3380<p>Well adding support for new encoding, or overriding one of the encoders
Daniel Veillardabfca612004-01-07 23:38:02 +00003381(assuming it is buggy) should not be hard, just write input and output
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00003382conversion routines to/from UTF-8, and register them using
3383xmlNewCharEncodingHandler(name, xxxToUTF8, UTF8Toxxx), and they will be
3384called automatically if the parser(s) encounter such an encoding name
3385(register it uppercase, this will help). The description of the encoders,
3386their arguments and expected return values are described in the encoding.h
3387header.</p>
3388
3389<p>A quick note on the topic of subverting the parser to use a different
3390internal encoding than UTF-8, in some case people will absolutely want to
3391keep the internal encoding different, I think it's still possible (but the
3392encoding must be compliant with ASCII on the same subrange) though I didn't
3393tried it. The key is to override the default conversion routines (by
3394registering null encoders/decoders for your charsets), and bypass the UTF-8
3395checking of the parser by setting the parser context charset
3396(ctxt-&gt;charset) to something different than XML_CHAR_ENCODING_UTF8, but
Daniel Veillard63d83142002-05-20 06:51:05 +00003397there is no guarantee that this will work. You may also have some troubles
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00003398saving back.</p>
3399
3400<p>Basically proper I18N support is important, this requires at least
3401libxml-2.0.0, but a lot of features and corrections are really available only
3402starting 2.2.</p>
3403
3404<h2><a name="IO">I/O Interfaces</a></h2>
3405
3406<p>Table of Content:</p>
3407<ol>
3408 <li><a href="#General1">General overview</a></li>
3409 <li><a href="#basic">The basic buffer type</a></li>
3410 <li><a href="#Input">Input I/O handlers</a></li>
3411 <li><a href="#Output">Output I/O handlers</a></li>
3412 <li><a href="#entities">The entities loader</a></li>
3413 <li><a href="#Example2">Example of customized I/O</a></li>
3414</ol>
3415
3416<h3><a name="General1">General overview</a></h3>
3417
3418<p>The module <code><a
3419href="http://xmlsoft.org/html/libxml-xmlio.html">xmlIO.h</a></code> provides
Daniel Veillard8a469172003-06-12 16:05:07 +00003420the interfaces to the libxml2 I/O system. This consists of 4 main parts:</p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00003421<ul>
3422 <li>Entities loader, this is a routine which tries to fetch the entities
3423 (files) based on their PUBLIC and SYSTEM identifiers. The default loader
Daniel Veillard8a469172003-06-12 16:05:07 +00003424 don't look at the public identifier since libxml2 do not maintain a
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00003425 catalog. You can redefine you own entity loader by using
3426 <code>xmlGetExternalEntityLoader()</code> and
Daniel Veillard9c466822001-10-25 12:03:39 +00003427 <code>xmlSetExternalEntityLoader()</code>. <a href="#entities">Check the
3428 example</a>.</li>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00003429 <li>Input I/O buffers which are a commodity structure used by the parser(s)
3430 input layer to handle fetching the informations to feed the parser. This
3431 provides buffering and is also a placeholder where the encoding
Daniel Veillard63d83142002-05-20 06:51:05 +00003432 converters to UTF8 are piggy-backed.</li>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00003433 <li>Output I/O buffers are similar to the Input ones and fulfill similar
3434 task but when generating a serialization from a tree.</li>
3435 <li>A mechanism to register sets of I/O callbacks and associate them with
3436 specific naming schemes like the protocol part of the URIs.
3437 <p>This affect the default I/O operations and allows to use specific I/O
3438 handlers for certain names.</p>
3439 </li>
3440</ul>
3441
3442<p>The general mechanism used when loading http://rpmfind.net/xml.html for
3443example in the HTML parser is the following:</p>
3444<ol>
3445 <li>The default entity loader calls <code>xmlNewInputFromFile()</code> with
3446 the parsing context and the URI string.</li>
3447 <li>the URI string is checked against the existing registered handlers
3448 using their match() callback function, if the HTTP module was compiled
3449 in, it is registered and its match() function will succeeds</li>
3450 <li>the open() function of the handler is called and if successful will
3451 return an I/O Input buffer</li>
3452 <li>the parser will the start reading from this buffer and progressively
3453 fetch information from the resource, calling the read() function of the
3454 handler until the resource is exhausted</li>
3455 <li>if an encoding change is detected it will be installed on the input
3456 buffer, providing buffering and efficient use of the conversion
3457 routines</li>
3458 <li>once the parser has finished, the close() function of the handler is
Daniel Veillard63d83142002-05-20 06:51:05 +00003459 called once and the Input buffer and associated resources are
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00003460 deallocated.</li>
3461</ol>
3462
3463<p>The user defined callbacks are checked first to allow overriding of the
Daniel Veillard8a469172003-06-12 16:05:07 +00003464default libxml2 I/O routines.</p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00003465
3466<h3><a name="basic">The basic buffer type</a></h3>
3467
3468<p>All the buffer manipulation handling is done using the
3469<code>xmlBuffer</code> type define in <code><a
3470href="http://xmlsoft.org/html/libxml-tree.html">tree.h</a> </code>which is a
3471resizable memory buffer. The buffer allocation strategy can be selected to be
3472either best-fit or use an exponential doubling one (CPU vs. memory use
Daniel Veillard63d83142002-05-20 06:51:05 +00003473trade-off). The values are <code>XML_BUFFER_ALLOC_EXACT</code> and
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00003474<code>XML_BUFFER_ALLOC_DOUBLEIT</code>, and can be set individually or on a
3475system wide basis using <code>xmlBufferSetAllocationScheme()</code>. A number
3476of functions allows to manipulate buffers with names starting with the
3477<code>xmlBuffer...</code> prefix.</p>
3478
3479<h3><a name="Input">Input I/O handlers</a></h3>
3480
3481<p>An Input I/O handler is a simple structure
3482<code>xmlParserInputBuffer</code> containing a context associated to the
3483resource (file descriptor, or pointer to a protocol handler), the read() and
3484close() callbacks to use and an xmlBuffer. And extra xmlBuffer and a charset
3485encoding handler are also present to support charset conversion when
3486needed.</p>
3487
3488<h3><a name="Output">Output I/O handlers</a></h3>
3489
3490<p>An Output handler <code>xmlOutputBuffer</code> is completely similar to an
3491Input one except the callbacks are write() and close().</p>
3492
3493<h3><a name="entities">The entities loader</a></h3>
3494
3495<p>The entity loader resolves requests for new entities and create inputs for
3496the parser. Creating an input from a filename or an URI string is done
3497through the xmlNewInputFromFile() routine. The default entity loader do not
3498handle the PUBLIC identifier associated with an entity (if any). So it just
3499calls xmlNewInputFromFile() with the SYSTEM identifier (which is mandatory in
3500XML).</p>
3501
3502<p>If you want to hook up a catalog mechanism then you simply need to
3503override the default entity loader, here is an example:</p>
3504<pre>#include &lt;libxml/xmlIO.h&gt;
3505
3506xmlExternalEntityLoader defaultLoader = NULL;
3507
3508xmlParserInputPtr
3509xmlMyExternalEntityLoader(const char *URL, const char *ID,
3510 xmlParserCtxtPtr ctxt) {
3511 xmlParserInputPtr ret;
3512 const char *fileID = NULL;
3513 /* lookup for the fileID depending on ID */
3514
3515 ret = xmlNewInputFromFile(ctxt, fileID);
3516 if (ret != NULL)
3517 return(ret);
3518 if (defaultLoader != NULL)
3519 ret = defaultLoader(URL, ID, ctxt);
3520 return(ret);
3521}
3522
3523int main(..) {
3524 ...
3525
3526 /*
3527 * Install our own entity loader
3528 */
3529 defaultLoader = xmlGetExternalEntityLoader();
3530 xmlSetExternalEntityLoader(xmlMyExternalEntityLoader);
3531
3532 ...
3533}</pre>
3534
3535<h3><a name="Example2">Example of customized I/O</a></h3>
3536
3537<p>This example come from <a href="http://xmlsoft.org/messages/0708.html">a
3538real use case</a>, xmlDocDump() closes the FILE * passed by the application
3539and this was a problem. The <a
3540href="http://xmlsoft.org/messages/0711.html">solution</a> was to redefine a
3541new output handler with the closing call deactivated:</p>
3542<ol>
Daniel Veillardc0801af2002-05-28 16:28:42 +00003543 <li>First define a new I/O output allocator where the output don't close
3544 the file:
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00003545 <pre>xmlOutputBufferPtr
3546xmlOutputBufferCreateOwn(FILE *file, xmlCharEncodingHandlerPtr encoder) {
3547    xmlOutputBufferPtr ret;
3548    
3549    if (xmlOutputCallbackInitialized == 0)
3550        xmlRegisterDefaultOutputCallbacks();
3551
3552    if (file == NULL) return(NULL);
3553    ret = xmlAllocOutputBuffer(encoder);
3554    if (ret != NULL) {
3555        ret-&gt;context = file;
3556        ret-&gt;writecallback = xmlFileWrite;
3557        ret-&gt;closecallback = NULL; /* No close callback */
3558    }
Daniel Veillardf83a2c72003-04-08 13:48:40 +00003559    return(ret);
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00003560} </pre>
3561 </li>
3562 <li>And then use it to save the document:
3563 <pre>FILE *f;
3564xmlOutputBufferPtr output;
3565xmlDocPtr doc;
3566int res;
3567
3568f = ...
3569doc = ....
3570
3571output = xmlOutputBufferCreateOwn(f, NULL);
3572res = xmlSaveFileTo(output, doc, NULL);
3573 </pre>
3574 </li>
3575</ol>
3576
3577<h2><a name="Catalog">Catalog support</a></h2>
3578
3579<p>Table of Content:</p>
3580<ol>
3581 <li><a href="General2">General overview</a></li>
3582 <li><a href="#definition">The definition</a></li>
3583 <li><a href="#Simple">Using catalogs</a></li>
3584 <li><a href="#Some">Some examples</a></li>
3585 <li><a href="#reference">How to tune catalog usage</a></li>
3586 <li><a href="#validate">How to debug catalog processing</a></li>
3587 <li><a href="#Declaring">How to create and maintain catalogs</a></li>
3588 <li><a href="#implemento">The implementor corner quick review of the
3589 API</a></li>
3590 <li><a href="#Other">Other resources</a></li>
3591</ol>
3592
3593<h3><a name="General2">General overview</a></h3>
3594
3595<p>What is a catalog? Basically it's a lookup mechanism used when an entity
3596(a file or a remote resource) references another entity. The catalog lookup
3597is inserted between the moment the reference is recognized by the software
3598(XML parser, stylesheet processing, or even images referenced for inclusion
3599in a rendering) and the time where loading that resource is actually
3600started.</p>
3601
3602<p>It is basically used for 3 things:</p>
3603<ul>
3604 <li>mapping from "logical" names, the public identifiers and a more
3605 concrete name usable for download (and URI). For example it can associate
3606 the logical name
3607 <p>"-//OASIS//DTD DocBook XML V4.1.2//EN"</p>
3608 <p>of the DocBook 4.1.2 XML DTD with the actual URL where it can be
3609 downloaded</p>
3610 <p>http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd</p>
3611 </li>
3612 <li>remapping from a given URL to another one, like an HTTP indirection
3613 saying that
3614 <p>"http://www.oasis-open.org/committes/tr.xsl"</p>
3615 <p>should really be looked at</p>
3616 <p>"http://www.oasis-open.org/committes/entity/stylesheets/base/tr.xsl"</p>
3617 </li>
3618 <li>providing a local cache mechanism allowing to load the entities
3619 associated to public identifiers or remote resources, this is a really
3620 important feature for any significant deployment of XML or SGML since it
3621 allows to avoid the aleas and delays associated to fetching remote
3622 resources.</li>
3623</ul>
3624
3625<h3><a name="definition">The definitions</a></h3>
3626
3627<p>Libxml, as of 2.4.3 implements 2 kind of catalogs:</p>
3628<ul>
3629 <li>the older SGML catalogs, the official spec is SGML Open Technical
3630 Resolution TR9401:1997, but is better understood by reading <a
3631 href="http://www.jclark.com/sp/catalog.htm">the SP Catalog page</a> from
3632 James Clark. This is relatively old and not the preferred mode of
3633 operation of libxml.</li>
3634 <li><a href="http://www.oasis-open.org/committees/entity/spec.html">XML
Daniel Veillardaf43f632002-03-08 15:05:20 +00003635 Catalogs</a> is far more flexible, more recent, uses an XML syntax and
3636 should scale quite better. This is the default option of libxml.</li>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00003637</ul>
3638
3639<p></p>
3640
3641<h3><a name="Simple">Using catalog</a></h3>
3642
Daniel Veillard8a469172003-06-12 16:05:07 +00003643<p>In a normal environment libxml2 will by default check the presence of a
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00003644catalog in /etc/xml/catalog, and assuming it has been correctly populated,
3645the processing is completely transparent to the document user. To take a
3646concrete example, suppose you are authoring a DocBook document, this one
3647starts with the following DOCTYPE definition:</p>
3648<pre>&lt;?xml version='1.0'?&gt;
3649&lt;!DOCTYPE book PUBLIC "-//Norman Walsh//DTD DocBk XML V3.1.4//EN"
3650 "http://nwalsh.com/docbook/xml/3.1.4/db3xml.dtd"&gt;</pre>
3651
3652<p>When validating the document with libxml, the catalog will be
3653automatically consulted to lookup the public identifier "-//Norman Walsh//DTD
3654DocBk XML V3.1.4//EN" and the system identifier
3655"http://nwalsh.com/docbook/xml/3.1.4/db3xml.dtd", and if these entities have
3656been installed on your system and the catalogs actually point to them, libxml
3657will fetch them from the local disk.</p>
3658
3659<p style="font-size: 10pt"><strong>Note</strong>: Really don't use this
3660DOCTYPE example it's a really old version, but is fine as an example.</p>
3661
Daniel Veillard8a469172003-06-12 16:05:07 +00003662<p>Libxml2 will check the catalog each time that it is requested to load an
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00003663entity, this includes DTD, external parsed entities, stylesheets, etc ... If
3664your system is correctly configured all the authoring phase and processing
3665should use only local files, even if your document stays portable because it
3666uses the canonical public and system ID, referencing the remote document.</p>
3667
3668<h3><a name="Some">Some examples:</a></h3>
3669
Daniel Veillard8a469172003-06-12 16:05:07 +00003670<p>Here is a couple of fragments from XML Catalogs used in libxml2 early
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00003671regression tests in <code>test/catalogs</code> :</p>
3672<pre>&lt;?xml version="1.0"?&gt;
3673&lt;!DOCTYPE catalog PUBLIC
3674 "-//OASIS//DTD Entity Resolution XML Catalog V1.0//EN"
3675 "http://www.oasis-open.org/committees/entity/release/1.0/catalog.dtd"&gt;
3676&lt;catalog xmlns="urn:oasis:names:tc:entity:xmlns:xml:catalog"&gt;
3677 &lt;public publicId="-//OASIS//DTD DocBook XML V4.1.2//EN"
3678 uri="http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd"/&gt;
3679...</pre>
3680
3681<p>This is the beginning of a catalog for DocBook 4.1.2, XML Catalogs are
3682written in XML, there is a specific namespace for catalog elements
3683"urn:oasis:names:tc:entity:xmlns:xml:catalog". The first entry in this
3684catalog is a <code>public</code> mapping it allows to associate a Public
3685Identifier with an URI.</p>
3686<pre>...
3687 &lt;rewriteSystem systemIdStartString="http://www.oasis-open.org/docbook/"
3688 rewritePrefix="file:///usr/share/xml/docbook/"/&gt;
3689...</pre>
3690
3691<p>A <code>rewriteSystem</code> is a very powerful instruction, it says that
3692any URI starting with a given prefix should be looked at another URI
3693constructed by replacing the prefix with an new one. In effect this acts like
3694a cache system for a full area of the Web. In practice it is extremely useful
3695with a file prefix if you have installed a copy of those resources on your
3696local system.</p>
3697<pre>...
3698&lt;delegatePublic publicIdStartString="-//OASIS//DTD XML Catalog //"
3699 catalog="file:///usr/share/xml/docbook.xml"/&gt;
3700&lt;delegatePublic publicIdStartString="-//OASIS//ENTITIES DocBook XML"
3701 catalog="file:///usr/share/xml/docbook.xml"/&gt;
3702&lt;delegatePublic publicIdStartString="-//OASIS//DTD DocBook XML"
3703 catalog="file:///usr/share/xml/docbook.xml"/&gt;
3704&lt;delegateSystem systemIdStartString="http://www.oasis-open.org/docbook/"
3705 catalog="file:///usr/share/xml/docbook.xml"/&gt;
3706&lt;delegateURI uriStartString="http://www.oasis-open.org/docbook/"
3707 catalog="file:///usr/share/xml/docbook.xml"/&gt;
3708...</pre>
3709
3710<p>Delegation is the core features which allows to build a tree of catalogs,
3711easier to maintain than a single catalog, based on Public Identifier, System
3712Identifier or URI prefixes it instructs the catalog software to look up
3713entries in another resource. This feature allow to build hierarchies of
3714catalogs, the set of entries presented should be sufficient to redirect the
3715resolution of all DocBook references to the specific catalog in
3716<code>/usr/share/xml/docbook.xml</code> this one in turn could delegate all
3717references for DocBook 4.2.1 to a specific catalog installed at the same time
3718as the DocBook resources on the local machine.</p>
3719
3720<h3><a name="reference">How to tune catalog usage:</a></h3>
3721
3722<p>The user can change the default catalog behaviour by redirecting queries
3723to its own set of catalogs, this can be done by setting the
3724<code>XML_CATALOG_FILES</code> environment variable to a list of catalogs, an
3725empty one should deactivate loading the default <code>/etc/xml/catalog</code>
3726default catalog</p>
3727
3728<h3><a name="validate">How to debug catalog processing:</a></h3>
3729
3730<p>Setting up the <code>XML_DEBUG_CATALOG</code> environment variable will
Daniel Veillard8a469172003-06-12 16:05:07 +00003731make libxml2 output debugging informations for each catalog operations, for
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00003732example:</p>
3733<pre>orchis:~/XML -&gt; xmllint --memory --noout test/ent2
3734warning: failed to load external entity "title.xml"
3735orchis:~/XML -&gt; export XML_DEBUG_CATALOG=
3736orchis:~/XML -&gt; xmllint --memory --noout test/ent2
3737Failed to parse catalog /etc/xml/catalog
3738Failed to parse catalog /etc/xml/catalog
3739warning: failed to load external entity "title.xml"
3740Catalogs cleanup
3741orchis:~/XML -&gt; </pre>
3742
3743<p>The test/ent2 references an entity, running the parser from memory makes
3744the base URI unavailable and the the "title.xml" entity cannot be loaded.
3745Setting up the debug environment variable allows to detect that an attempt is
3746made to load the <code>/etc/xml/catalog</code> but since it's not present the
3747resolution fails.</p>
3748
3749<p>But the most advanced way to debug XML catalog processing is to use the
3750<strong>xmlcatalog</strong> command shipped with libxml2, it allows to load
3751catalogs and make resolution queries to see what is going on. This is also
3752used for the regression tests:</p>
3753<pre>orchis:~/XML -&gt; ./xmlcatalog test/catalogs/docbook.xml \
3754 "-//OASIS//DTD DocBook XML V4.1.2//EN"
3755http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd
3756orchis:~/XML -&gt; </pre>
3757
3758<p>For debugging what is going on, adding one -v flags increase the verbosity
3759level to indicate the processing done (adding a second flag also indicate
3760what elements are recognized at parsing):</p>
3761<pre>orchis:~/XML -&gt; ./xmlcatalog -v test/catalogs/docbook.xml \
3762 "-//OASIS//DTD DocBook XML V4.1.2//EN"
3763Parsing catalog test/catalogs/docbook.xml's content
3764Found public match -//OASIS//DTD DocBook XML V4.1.2//EN
3765http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd
3766Catalogs cleanup
3767orchis:~/XML -&gt; </pre>
3768
3769<p>A shell interface is also available to debug and process multiple queries
3770(and for regression tests):</p>
3771<pre>orchis:~/XML -&gt; ./xmlcatalog -shell test/catalogs/docbook.xml \
3772 "-//OASIS//DTD DocBook XML V4.1.2//EN"
3773&gt; help
3774Commands available:
3775public PublicID: make a PUBLIC identifier lookup
3776system SystemID: make a SYSTEM identifier lookup
3777resolve PublicID SystemID: do a full resolver lookup
3778add 'type' 'orig' 'replace' : add an entry
3779del 'values' : remove values
3780dump: print the current catalog state
3781debug: increase the verbosity level
3782quiet: decrease the verbosity level
3783exit: quit the shell
3784&gt; public "-//OASIS//DTD DocBook XML V4.1.2//EN"
3785http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd
3786&gt; quit
3787orchis:~/XML -&gt; </pre>
3788
3789<p>This should be sufficient for most debugging purpose, this was actually
3790used heavily to debug the XML Catalog implementation itself.</p>
3791
3792<h3><a name="Declaring">How to create and maintain</a> catalogs:</h3>
3793
3794<p>Basically XML Catalogs are XML files, you can either use XML tools to
3795manage them or use <strong>xmlcatalog</strong> for this. The basic step is
3796to create a catalog the -create option provide this facility:</p>
3797<pre>orchis:~/XML -&gt; ./xmlcatalog --create tst.xml
3798&lt;?xml version="1.0"?&gt;
3799&lt;!DOCTYPE catalog PUBLIC "-//OASIS//DTD Entity Resolution XML Catalog V1.0//EN"
3800 "http://www.oasis-open.org/committees/entity/release/1.0/catalog.dtd"&gt;
3801&lt;catalog xmlns="urn:oasis:names:tc:entity:xmlns:xml:catalog"/&gt;
3802orchis:~/XML -&gt; </pre>
3803
3804<p>By default xmlcatalog does not overwrite the original catalog and save the
3805result on the standard output, this can be overridden using the -noout
3806option. The <code>-add</code> command allows to add entries in the
3807catalog:</p>
3808<pre>orchis:~/XML -&gt; ./xmlcatalog --noout --create --add "public" \
3809 "-//OASIS//DTD DocBook XML V4.1.2//EN" \
3810 http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd tst.xml
3811orchis:~/XML -&gt; cat tst.xml
3812&lt;?xml version="1.0"?&gt;
3813&lt;!DOCTYPE catalog PUBLIC "-//OASIS//DTD Entity Resolution XML Catalog V1.0//EN" \
3814 "http://www.oasis-open.org/committees/entity/release/1.0/catalog.dtd"&gt;
3815&lt;catalog xmlns="urn:oasis:names:tc:entity:xmlns:xml:catalog"&gt;
3816&lt;public publicId="-//OASIS//DTD DocBook XML V4.1.2//EN"
3817 uri="http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd"/&gt;
3818&lt;/catalog&gt;
3819orchis:~/XML -&gt; </pre>
3820
3821<p>The <code>-add</code> option will always take 3 parameters even if some of
3822the XML Catalog constructs (like nextCatalog) will have only a single
3823argument, just pass a third empty string, it will be ignored.</p>
3824
3825<p>Similarly the <code>-del</code> option remove matching entries from the
3826catalog:</p>
3827<pre>orchis:~/XML -&gt; ./xmlcatalog --del \
3828 "http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd" tst.xml
3829&lt;?xml version="1.0"?&gt;
3830&lt;!DOCTYPE catalog PUBLIC "-//OASIS//DTD Entity Resolution XML Catalog V1.0//EN"
3831 "http://www.oasis-open.org/committees/entity/release/1.0/catalog.dtd"&gt;
3832&lt;catalog xmlns="urn:oasis:names:tc:entity:xmlns:xml:catalog"/&gt;
3833orchis:~/XML -&gt; </pre>
3834
3835<p>The catalog is now empty. Note that the matching of <code>-del</code> is
3836exact and would have worked in a similar fashion with the Public ID
3837string.</p>
3838
3839<p>This is rudimentary but should be sufficient to manage a not too complex
3840catalog tree of resources.</p>
3841
3842<h3><a name="implemento">The implementor corner quick review of the
3843API:</a></h3>
3844
3845<p>First, and like for every other module of libxml, there is an
3846automatically generated <a href="html/libxml-catalog.html">API page for
3847catalog support</a>.</p>
3848
3849<p>The header for the catalog interfaces should be included as:</p>
3850<pre>#include &lt;libxml/catalog.h&gt;</pre>
3851
3852<p>The API is voluntarily kept very simple. First it is not obvious that
3853applications really need access to it since it is the default behaviour of
Daniel Veillard560c2a42003-07-06 21:13:49 +00003854libxml2 (Note: it is possible to completely override libxml2 default catalog
3855by using <a href="html/libxml-parser.html">xmlSetExternalEntityLoader</a> to
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00003856plug an application specific resolver).</p>
3857
Daniel Veillard8a469172003-06-12 16:05:07 +00003858<p>Basically libxml2 support 2 catalog lists:</p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00003859<ul>
3860 <li>the default one, global shared by all the application</li>
3861 <li>a per-document catalog, this one is built if the document uses the
3862 <code>oasis-xml-catalog</code> PIs to specify its own catalog list, it is
3863 associated to the parser context and destroyed when the parsing context
3864 is destroyed.</li>
3865</ul>
3866
3867<p>the document one will be used first if it exists.</p>
3868
3869<h4>Initialization routines:</h4>
3870
3871<p>xmlInitializeCatalog(), xmlLoadCatalog() and xmlLoadCatalogs() should be
3872used at startup to initialize the catalog, if the catalog should be
3873initialized with specific values xmlLoadCatalog() or xmlLoadCatalogs()
3874should be called before xmlInitializeCatalog() which would otherwise do a
3875default initialization first.</p>
3876
3877<p>The xmlCatalogAddLocal() call is used by the parser to grow the document
3878own catalog list if needed.</p>
3879
3880<h4>Preferences setup:</h4>
3881
3882<p>The XML Catalog spec requires the possibility to select default
3883preferences between public and system delegation,
3884xmlCatalogSetDefaultPrefer() allows this, xmlCatalogSetDefaults() and
3885xmlCatalogGetDefaults() allow to control if XML Catalogs resolution should
3886be forbidden, allowed for global catalog, for document catalog or both, the
3887default is to allow both.</p>
3888
3889<p>And of course xmlCatalogSetDebug() allows to generate debug messages
3890(through the xmlGenericError() mechanism).</p>
3891
3892<h4>Querying routines:</h4>
3893
3894<p>xmlCatalogResolve(), xmlCatalogResolveSystem(), xmlCatalogResolvePublic()
3895and xmlCatalogResolveURI() are relatively explicit if you read the XML
3896Catalog specification they correspond to section 7 algorithms, they should
3897also work if you have loaded an SGML catalog with a simplified semantic.</p>
3898
3899<p>xmlCatalogLocalResolve() and xmlCatalogLocalResolveURI() are the same but
3900operate on the document catalog list</p>
3901
3902<h4>Cleanup and Miscellaneous:</h4>
3903
3904<p>xmlCatalogCleanup() free-up the global catalog, xmlCatalogFreeLocal() is
3905the per-document equivalent.</p>
3906
3907<p>xmlCatalogAdd() and xmlCatalogRemove() are used to dynamically modify the
3908first catalog in the global list, and xmlCatalogDump() allows to dump a
3909catalog state, those routines are primarily designed for xmlcatalog, I'm not
3910sure that exposing more complex interfaces (like navigation ones) would be
3911really useful.</p>
3912
3913<p>The xmlParseCatalogFile() is a function used to load XML Catalog files,
3914it's similar as xmlParseFile() except it bypass all catalog lookups, it's
3915provided because this functionality may be useful for client tools.</p>
3916
3917<h4>threaded environments:</h4>
3918
3919<p>Since the catalog tree is built progressively, some care has been taken to
3920try to avoid troubles in multithreaded environments. The code is now thread
Daniel Veillard8a469172003-06-12 16:05:07 +00003921safe assuming that the libxml2 library has been compiled with threads
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00003922support.</p>
3923
3924<p></p>
3925
3926<h3><a name="Other">Other resources</a></h3>
3927
3928<p>The XML Catalog specification is relatively recent so there isn't much
3929literature to point at:</p>
3930<ul>
Daniel Veillard63d83142002-05-20 06:51:05 +00003931 <li>You can find a good rant from Norm Walsh about <a
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00003932 href="http://www.arbortext.com/Think_Tank/XML_Resources/Issue_Three/issue_three.html">the
3933 need for catalogs</a>, it provides a lot of context informations even if
Daniel Veillard93d3a472002-04-26 14:04:55 +00003934 I don't agree with everything presented. Norm also wrote a more recent
3935 article <a
3936 href="http://wwws.sun.com/software/xml/developers/resolver/article/">XML
3937 entities and URI resolvers</a> describing them.</li>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00003938 <li>An <a href="http://home.ccil.org/~cowan/XML/XCatalog.html">old XML
3939 catalog proposal</a> from John Cowan</li>
3940 <li>The <a href="http://www.rddl.org/">Resource Directory Description
3941 Language</a> (RDDL) another catalog system but more oriented toward
3942 providing metadata for XML namespaces.</li>
3943 <li>the page from the OASIS Technical <a
3944 href="http://www.oasis-open.org/committees/entity/">Committee on Entity
3945 Resolution</a> who maintains XML Catalog, you will find pointers to the
3946 specification update, some background and pointers to others tools
3947 providing XML Catalog support</li>
Daniel Veillardabfca612004-01-07 23:38:02 +00003948 <li>There is a <a href="buildDocBookCatalog">shell script</a> to generate
Daniel Veillard35e937a2002-01-19 22:21:54 +00003949 XML Catalogs for DocBook 4.1.2 . If it can write to the /etc/xml/
3950 directory, it will set-up /etc/xml/catalog and /etc/xml/docbook based on
3951 the resources found on the system. Otherwise it will just create
3952 ~/xmlcatalog and ~/dbkxmlcatalog and doing:
Daniel Veillard8594de92003-04-25 10:08:44 +00003953 <p><code>export XML_CATALOG_FILES=$HOME/xmlcatalog</code></p>
Daniel Veillard35e937a2002-01-19 22:21:54 +00003954 <p>should allow to process DocBook documentations without requiring
Daniel Veillard63d83142002-05-20 06:51:05 +00003955 network accesses for the DTD or stylesheets</p>
Daniel Veillard35e937a2002-01-19 22:21:54 +00003956 </li>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00003957 <li>I have uploaded <a href="ftp://xmlsoft.org/test/dbk412catalog.tar.gz">a
Daniel Veillard35e937a2002-01-19 22:21:54 +00003958 small tarball</a> containing XML Catalogs for DocBook 4.1.2 which seems
3959 to work fine for me too</li>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00003960 <li>The <a href="http://www.xmlsoft.org/xmlcatalog_man.html">xmlcatalog
3961 manual page</a></li>
3962</ul>
3963
3964<p>If you have suggestions for corrections or additions, simply contact
3965me:</p>
3966
3967<h2><a name="library">The parser interfaces</a></h2>
Daniel Veillardb05deb71999-08-10 19:04:08 +00003968
3969<p>This section is directly intended to help programmers getting bootstrapped
Daniel Veillard8a469172003-06-12 16:05:07 +00003970using the XML tollkit from the C language. It is not intended to be
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +00003971extensive. I hope the automatically generated documents will provide the
3972completeness required, but as a separate set of documents. The interfaces of
Daniel Veillard560c2a42003-07-06 21:13:49 +00003973the XML parser are by principle low level, Those interested in a higher level
3974API should <a href="#DOM">look at DOM</a>.</p>
Daniel Veillardccb09631998-10-27 06:21:04 +00003975
Daniel Veillard9cb5ff42001-01-29 08:22:21 +00003976<p>The <a href="html/libxml-parser.html">parser interfaces for XML</a> are
3977separated from the <a href="html/libxml-htmlparser.html">HTML parser
Daniel Veillard88f00ae2000-03-02 00:15:55 +00003978interfaces</a>. Let's have a look at how the XML parser can be called:</p>
Daniel Veillard0142b842000-01-14 14:45:24 +00003979
Daniel Veillard88f00ae2000-03-02 00:15:55 +00003980<h3><a name="Invoking">Invoking the parser : the pull method</a></h3>
Daniel Veillardb05deb71999-08-10 19:04:08 +00003981
Daniel Veillard88f00ae2000-03-02 00:15:55 +00003982<p>Usually, the first thing to do is to read an XML input. The parser accepts
3983documents either from in-memory strings or from files. The functions are
Daniel Veillardb05deb71999-08-10 19:04:08 +00003984defined in "parser.h":</p>
Daniel Veillard10c6a8f1998-10-28 01:00:12 +00003985<dl>
Daniel Veillardb05deb71999-08-10 19:04:08 +00003986 <dt><code>xmlDocPtr xmlParseMemory(char *buffer, int size);</code></dt>
Daniel Veillard88f00ae2000-03-02 00:15:55 +00003987 <dd><p>Parse a null-terminated string containing the document.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +00003988 </dd>
Daniel Veillard10c6a8f1998-10-28 01:00:12 +00003989</dl>
3990<dl>
Daniel Veillardb05deb71999-08-10 19:04:08 +00003991 <dt><code>xmlDocPtr xmlParseFile(const char *filename);</code></dt>
Daniel Veillardf13e1ed2000-03-06 07:41:49 +00003992 <dd><p>Parse an XML document contained in a (possibly compressed)
3993 file.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +00003994 </dd>
Daniel Veillard10c6a8f1998-10-28 01:00:12 +00003995</dl>
Daniel Veillardb05deb71999-08-10 19:04:08 +00003996
Daniel Veillard88f00ae2000-03-02 00:15:55 +00003997<p>The parser returns a pointer to the document structure (or NULL in case of
Daniel Veillard10c6a8f1998-10-28 01:00:12 +00003998failure).</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +00003999
Daniel Veillard88f00ae2000-03-02 00:15:55 +00004000<h3 id="Invoking1">Invoking the parser: the push method</h3>
Daniel Veillard0142b842000-01-14 14:45:24 +00004001
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +00004002<p>In order for the application to keep the control when the document is
Daniel Veillard560c2a42003-07-06 21:13:49 +00004003being fetched (which is common for GUI based programs) libxml2 provides a
4004push interface, too, as of version 1.8.3. Here are the interface
4005functions:</p>
Daniel Veillard0142b842000-01-14 14:45:24 +00004006<pre>xmlParserCtxtPtr xmlCreatePushParserCtxt(xmlSAXHandlerPtr sax,
4007 void *user_data,
4008 const char *chunk,
4009 int size,
4010 const char *filename);
4011int xmlParseChunk (xmlParserCtxtPtr ctxt,
4012 const char *chunk,
4013 int size,
4014 int terminate);</pre>
4015
Daniel Veillard88f00ae2000-03-02 00:15:55 +00004016<p>and here is a simple example showing how to use the interface:</p>
Daniel Veillard0142b842000-01-14 14:45:24 +00004017<pre> FILE *f;
4018
4019 f = fopen(filename, "r");
4020 if (f != NULL) {
4021 int res, size = 1024;
4022 char chars[1024];
4023 xmlParserCtxtPtr ctxt;
4024
4025 res = fread(chars, 1, 4, f);
Daniel Veillard60979bd2000-07-10 12:17:33 +00004026 if (res &gt; 0) {
Daniel Veillard0142b842000-01-14 14:45:24 +00004027 ctxt = xmlCreatePushParserCtxt(NULL, NULL,
4028 chars, res, filename);
Daniel Veillard60979bd2000-07-10 12:17:33 +00004029 while ((res = fread(chars, 1, size, f)) &gt; 0) {
Daniel Veillard0142b842000-01-14 14:45:24 +00004030 xmlParseChunk(ctxt, chars, res, 0);
4031 }
4032 xmlParseChunk(ctxt, chars, 0, 1);
Daniel Veillard60979bd2000-07-10 12:17:33 +00004033 doc = ctxt-&gt;myDoc;
Daniel Veillard0142b842000-01-14 14:45:24 +00004034 xmlFreeParserCtxt(ctxt);
4035 }
4036 }</pre>
4037
Daniel Veillard8a469172003-06-12 16:05:07 +00004038<p>The HTML parser embedded into libxml2 also has a push interface; the
Daniel Veillardec70e912001-02-26 20:10:45 +00004039functions are just prefixed by "html" rather than "xml".</p>
Daniel Veillard0142b842000-01-14 14:45:24 +00004040
4041<h3 id="Invoking2">Invoking the parser: the SAX interface</h3>
4042
Daniel Veillardec70e912001-02-26 20:10:45 +00004043<p>The tree-building interface makes the parser memory-hungry, first loading
4044the document in memory and then building the tree itself. Reading a document
4045without building the tree is possible using the SAX interfaces (see SAX.h and
4046<a href="http://www.daa.com.au/~james/gnome/xml-sax/xml-sax.html">James
Daniel Veillard88f00ae2000-03-02 00:15:55 +00004047Henstridge's documentation</a>). Note also that the push interface can be
Daniel Veillard91e9d582001-02-26 07:31:12 +00004048limited to SAX: just use the two first arguments of
Daniel Veillard0142b842000-01-14 14:45:24 +00004049<code>xmlCreatePushParserCtxt()</code>.</p>
Daniel Veillardccb09631998-10-27 06:21:04 +00004050
Daniel Veillard2f4dfc41999-09-24 14:03:48 +00004051<h3><a name="Building">Building a tree from scratch</a></h3>
Daniel Veillardb05deb71999-08-10 19:04:08 +00004052
4053<p>The other way to get an XML tree in memory is by building it. Basically
Daniel Veillardf13e1ed2000-03-06 07:41:49 +00004054there is a set of functions dedicated to building new elements. (These are
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +00004055also described in &lt;libxml/tree.h&gt;.) For example, here is a piece of
4056code that produces the XML document used in the previous examples:</p>
Daniel Veillard60979bd2000-07-10 12:17:33 +00004057<pre> #include &lt;libxml/tree.h&gt;
Daniel Veillard361d8452000-04-03 19:48:13 +00004058 xmlDocPtr doc;
Daniel Veillard25940b71998-10-29 05:51:30 +00004059 xmlNodePtr tree, subtree;
4060
4061 doc = xmlNewDoc("1.0");
Daniel Veillard60979bd2000-07-10 12:17:33 +00004062 doc-&gt;children = xmlNewDocNode(doc, NULL, "EXAMPLE", NULL);
4063 xmlSetProp(doc-&gt;children, "prop1", "gnome is great");
4064 xmlSetProp(doc-&gt;children, "prop2", "&amp; linux too");
4065 tree = xmlNewChild(doc-&gt;children, NULL, "head", NULL);
Daniel Veillard25940b71998-10-29 05:51:30 +00004066 subtree = xmlNewChild(tree, NULL, "title", "Welcome to Gnome");
Daniel Veillard60979bd2000-07-10 12:17:33 +00004067 tree = xmlNewChild(doc-&gt;children, NULL, "chapter", NULL);
Daniel Veillard25940b71998-10-29 05:51:30 +00004068 subtree = xmlNewChild(tree, NULL, "title", "The Linux adventure");
4069 subtree = xmlNewChild(tree, NULL, "p", "bla bla bla ...");
4070 subtree = xmlNewChild(tree, NULL, "image", NULL);
4071 xmlSetProp(subtree, "href", "linus.gif");</pre>
Daniel Veillardb05deb71999-08-10 19:04:08 +00004072
4073<p>Not really rocket science ...</p>
Daniel Veillard25940b71998-10-29 05:51:30 +00004074
Daniel Veillard2f4dfc41999-09-24 14:03:48 +00004075<h3><a name="Traversing">Traversing the tree</a></h3>
Daniel Veillardb05deb71999-08-10 19:04:08 +00004076
Daniel Veillard9cb5ff42001-01-29 08:22:21 +00004077<p>Basically by <a href="html/libxml-tree.html">including "tree.h"</a> your
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +00004078code has access to the internal structure of all the elements of the tree.
4079The names should be somewhat simple like <strong>parent</strong>,
Daniel Veillard306be992000-07-03 12:38:45 +00004080<strong>children</strong>, <strong>next</strong>, <strong>prev</strong>,
Daniel Veillard88f00ae2000-03-02 00:15:55 +00004081<strong>properties</strong>, etc... For example, still with the previous
Daniel Veillard0142b842000-01-14 14:45:24 +00004082example:</p>
Daniel Veillard60979bd2000-07-10 12:17:33 +00004083<pre><code>doc-&gt;children-&gt;children-&gt;children</code></pre>
Daniel Veillardb05deb71999-08-10 19:04:08 +00004084
4085<p>points to the title element,</p>
Daniel Veillard91e9d582001-02-26 07:31:12 +00004086<pre>doc-&gt;children-&gt;children-&gt;next-&gt;children-&gt;children</pre>
Daniel Veillardb05deb71999-08-10 19:04:08 +00004087
Daniel Veillardf13e1ed2000-03-06 07:41:49 +00004088<p>points to the text node containing the chapter title "The Linux
4089adventure".</p>
Daniel Veillard10c6a8f1998-10-28 01:00:12 +00004090
Daniel Veillardb24054a1999-12-18 15:32:46 +00004091<p><strong>NOTE</strong>: XML allows <em>PI</em>s and <em>comments</em> to be
Daniel Veillard60979bd2000-07-10 12:17:33 +00004092present before the document root, so <code>doc-&gt;children</code> may point
Daniel Veillard91e9d582001-02-26 07:31:12 +00004093to an element which is not the document Root Element; a function
Daniel Veillard5cb5ab81999-12-21 15:35:29 +00004094<code>xmlDocGetRootElement()</code> was added for this purpose.</p>
Daniel Veillardb24054a1999-12-18 15:32:46 +00004095
Daniel Veillard2f4dfc41999-09-24 14:03:48 +00004096<h3><a name="Modifying">Modifying the tree</a></h3>
Daniel Veillardb05deb71999-08-10 19:04:08 +00004097
Daniel Veillard88f00ae2000-03-02 00:15:55 +00004098<p>Functions are provided for reading and writing the document content. Here
Daniel Veillard9cb5ff42001-01-29 08:22:21 +00004099is an excerpt from the <a href="html/libxml-tree.html">tree API</a>:</p>
Daniel Veillard25940b71998-10-29 05:51:30 +00004100<dl>
Daniel Veillarddd6b3671999-09-23 22:19:22 +00004101 <dt><code>xmlAttrPtr xmlSetProp(xmlNodePtr node, const xmlChar *name, const
4102 xmlChar *value);</code></dt>
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +00004103 <dd><p>This sets (or changes) an attribute carried by an ELEMENT node.
4104 The value can be NULL.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +00004105 </dd>
Daniel Veillard25940b71998-10-29 05:51:30 +00004106</dl>
4107<dl>
Daniel Veillarddd6b3671999-09-23 22:19:22 +00004108 <dt><code>const xmlChar *xmlGetProp(xmlNodePtr node, const xmlChar
Daniel Veillardb05deb71999-08-10 19:04:08 +00004109 *name);</code></dt>
Daniel Veillardc92c3042000-09-29 02:42:04 +00004110 <dd><p>This function returns a pointer to new copy of the property
4111 content. Note that the user must deallocate the result.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +00004112 </dd>
Daniel Veillard25940b71998-10-29 05:51:30 +00004113</dl>
Daniel Veillardb05deb71999-08-10 19:04:08 +00004114
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +00004115<p>Two functions are provided for reading and writing the text associated
4116with elements:</p>
Daniel Veillard25940b71998-10-29 05:51:30 +00004117<dl>
Daniel Veillarddd6b3671999-09-23 22:19:22 +00004118 <dt><code>xmlNodePtr xmlStringGetNodeList(xmlDocPtr doc, const xmlChar
Daniel Veillardb05deb71999-08-10 19:04:08 +00004119 *value);</code></dt>
Daniel Veillardec70e912001-02-26 20:10:45 +00004120 <dd><p>This function takes an "external" string and converts it to one
4121 text node or possibly to a list of entity and text nodes. All
4122 non-predefined entity references like &amp;Gnome; will be stored
4123 internally as entity nodes, hence the result of the function may not be
4124 a single node.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +00004125 </dd>
Daniel Veillard25940b71998-10-29 05:51:30 +00004126</dl>
4127<dl>
Daniel Veillarddd6b3671999-09-23 22:19:22 +00004128 <dt><code>xmlChar *xmlNodeListGetString(xmlDocPtr doc, xmlNodePtr list, int
Daniel Veillardb05deb71999-08-10 19:04:08 +00004129 inLine);</code></dt>
Daniel Veillardf13e1ed2000-03-06 07:41:49 +00004130 <dd><p>This function is the inverse of
4131 <code>xmlStringGetNodeList()</code>. It generates a new string
4132 containing the content of the text and entity nodes. Note the extra
4133 argument inLine. If this argument is set to 1, the function will expand
4134 entity references. For example, instead of returning the &amp;Gnome;
4135 XML encoding in the string, it will substitute it with its value (say,
Daniel Veillard91e9d582001-02-26 07:31:12 +00004136 "GNU Network Object Model Environment").</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +00004137 </dd>
Daniel Veillard25940b71998-10-29 05:51:30 +00004138</dl>
Daniel Veillard10c6a8f1998-10-28 01:00:12 +00004139
Daniel Veillard2f4dfc41999-09-24 14:03:48 +00004140<h3><a name="Saving">Saving a tree</a></h3>
Daniel Veillardb05deb71999-08-10 19:04:08 +00004141
4142<p>Basically 3 options are possible:</p>
Daniel Veillard25940b71998-10-29 05:51:30 +00004143<dl>
Daniel Veillarddd6b3671999-09-23 22:19:22 +00004144 <dt><code>void xmlDocDumpMemory(xmlDocPtr cur, xmlChar**mem, int
Daniel Veillardb05deb71999-08-10 19:04:08 +00004145 *size);</code></dt>
Daniel Veillard88f00ae2000-03-02 00:15:55 +00004146 <dd><p>Returns a buffer into which the document has been saved.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +00004147 </dd>
Daniel Veillard25940b71998-10-29 05:51:30 +00004148</dl>
4149<dl>
Daniel Veillardb05deb71999-08-10 19:04:08 +00004150 <dt><code>extern void xmlDocDump(FILE *f, xmlDocPtr doc);</code></dt>
Daniel Veillard88f00ae2000-03-02 00:15:55 +00004151 <dd><p>Dumps a document to an open file descriptor.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +00004152 </dd>
Daniel Veillard25940b71998-10-29 05:51:30 +00004153</dl>
4154<dl>
Daniel Veillardb05deb71999-08-10 19:04:08 +00004155 <dt><code>int xmlSaveFile(const char *filename, xmlDocPtr cur);</code></dt>
Daniel Veillardf13e1ed2000-03-06 07:41:49 +00004156 <dd><p>Saves the document to a file. In this case, the compression
4157 interface is triggered if it has been turned on.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +00004158 </dd>
Daniel Veillard25940b71998-10-29 05:51:30 +00004159</dl>
Daniel Veillard10c6a8f1998-10-28 01:00:12 +00004160
Daniel Veillard2f4dfc41999-09-24 14:03:48 +00004161<h3><a name="Compressio">Compression</a></h3>
Daniel Veillardb05deb71999-08-10 19:04:08 +00004162
Daniel Veillard88f00ae2000-03-02 00:15:55 +00004163<p>The library transparently handles compression when doing file-based
Daniel Veillardf13e1ed2000-03-06 07:41:49 +00004164accesses. The level of compression on saves can be turned on either globally
4165or individually for one file:</p>
Daniel Veillard25940b71998-10-29 05:51:30 +00004166<dl>
Daniel Veillardb05deb71999-08-10 19:04:08 +00004167 <dt><code>int xmlGetDocCompressMode (xmlDocPtr doc);</code></dt>
Daniel Veillard88f00ae2000-03-02 00:15:55 +00004168 <dd><p>Gets the document compression ratio (0-9).</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +00004169 </dd>
Daniel Veillard25940b71998-10-29 05:51:30 +00004170</dl>
4171<dl>
Daniel Veillardb05deb71999-08-10 19:04:08 +00004172 <dt><code>void xmlSetDocCompressMode (xmlDocPtr doc, int mode);</code></dt>
Daniel Veillard88f00ae2000-03-02 00:15:55 +00004173 <dd><p>Sets the document compression ratio.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +00004174 </dd>
Daniel Veillard25940b71998-10-29 05:51:30 +00004175</dl>
4176<dl>
Daniel Veillardb05deb71999-08-10 19:04:08 +00004177 <dt><code>int xmlGetCompressMode(void);</code></dt>
Daniel Veillard88f00ae2000-03-02 00:15:55 +00004178 <dd><p>Gets the default compression ratio.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +00004179 </dd>
Daniel Veillard25940b71998-10-29 05:51:30 +00004180</dl>
4181<dl>
Daniel Veillardb05deb71999-08-10 19:04:08 +00004182 <dt><code>void xmlSetCompressMode(int mode);</code></dt>
Daniel Veillard88f00ae2000-03-02 00:15:55 +00004183 <dd><p>Sets the default compression ratio.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +00004184 </dd>
Daniel Veillard25940b71998-10-29 05:51:30 +00004185</dl>
4186
Daniel Veillard2f4dfc41999-09-24 14:03:48 +00004187<h2><a name="Entities">Entities or no entities</a></h2>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +00004188
Daniel Veillard88f00ae2000-03-02 00:15:55 +00004189<p>Entities in principle are similar to simple C macros. An entity defines an
4190abbreviation for a given string that you can reuse many times throughout the
4191content of your document. Entities are especially useful when a given string
Daniel Veillardf13e1ed2000-03-06 07:41:49 +00004192may occur frequently within a document, or to confine the change needed to a
4193document to a restricted area in the internal subset of the document (at the
4194beginning). Example:</p>
Daniel Veillard60979bd2000-07-10 12:17:33 +00004195<pre>1 &lt;?xml version="1.0"?&gt;
Daniel Veillardc8eab3a1999-09-04 18:27:23 +000041962 &lt;!DOCTYPE EXAMPLE SYSTEM "example.dtd" [
Daniel Veillard60979bd2000-07-10 12:17:33 +000041973 &lt;!ENTITY xml "Extensible Markup Language"&gt;
41984 ]&gt;
41995 &lt;EXAMPLE&gt;
Daniel Veillardc8eab3a1999-09-04 18:27:23 +000042006 &amp;xml;
Daniel Veillard60979bd2000-07-10 12:17:33 +000042017 &lt;/EXAMPLE&gt;</pre>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +00004202
4203<p>Line 3 declares the xml entity. Line 6 uses the xml entity, by prefixing
Daniel Veillard91e9d582001-02-26 07:31:12 +00004204its name with '&amp;' and following it by ';' without any spaces added. There
Daniel Veillard8a469172003-06-12 16:05:07 +00004205are 5 predefined entities in libxml2 allowing you to escape characters with
Daniel Veillardc8eab3a1999-09-04 18:27:23 +00004206predefined meaning in some parts of the xml document content:
Daniel Veillard88f00ae2000-03-02 00:15:55 +00004207<strong>&amp;lt;</strong> for the character '&lt;', <strong>&amp;gt;</strong>
Daniel Veillard60979bd2000-07-10 12:17:33 +00004208for the character '&gt;', <strong>&amp;apos;</strong> for the character ''',
Daniel Veillard88f00ae2000-03-02 00:15:55 +00004209<strong>&amp;quot;</strong> for the character '"', and
4210<strong>&amp;amp;</strong> for the character '&amp;'.</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +00004211
4212<p>One of the problems related to entities is that you may want the parser to
Daniel Veillardf13e1ed2000-03-06 07:41:49 +00004213substitute an entity's content so that you can see the replacement text in
4214your application. Or you may prefer to keep entity references as such in the
4215content to be able to save the document back without losing this usually
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +00004216precious information (if the user went through the pain of explicitly
4217defining entities, he may have a a rather negative attitude if you blindly
Daniel Veillard63d83142002-05-20 06:51:05 +00004218substitute them as saving time). The <a
Daniel Veillard5373ea12003-07-24 13:09:13 +00004219href="html/libxml-parser.html#xmlSubstituteEntitiesDefault">xmlSubstituteEntitiesDefault()</a>
Daniel Veillard88f00ae2000-03-02 00:15:55 +00004220function allows you to check and change the behaviour, which is to not
4221substitute entities by default.</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +00004222
Daniel Veillard8a469172003-06-12 16:05:07 +00004223<p>Here is the DOM tree built by libxml2 for the previous document in the
Daniel Veillardc8eab3a1999-09-04 18:27:23 +00004224default case:</p>
Daniel Veillard60979bd2000-07-10 12:17:33 +00004225<pre>/gnome/src/gnome-xml -&gt; ./xmllint --debug test/ent1
Daniel Veillardc8eab3a1999-09-04 18:27:23 +00004226DOCUMENT
4227version=1.0
4228 ELEMENT EXAMPLE
4229 TEXT
4230 content=
4231 ENTITY_REF
4232 INTERNAL_GENERAL_ENTITY xml
4233 content=Extensible Markup Language
4234 TEXT
4235 content=</pre>
4236
4237<p>And here is the result when substituting entities:</p>
Daniel Veillard60979bd2000-07-10 12:17:33 +00004238<pre>/gnome/src/gnome-xml -&gt; ./tester --debug --noent test/ent1
Daniel Veillardc8eab3a1999-09-04 18:27:23 +00004239DOCUMENT
4240version=1.0
4241 ELEMENT EXAMPLE
4242 TEXT
4243 content= Extensible Markup Language</pre>
4244
Daniel Veillard88f00ae2000-03-02 00:15:55 +00004245<p>So, entities or no entities? Basically, it depends on your use case. I
4246suggest that you keep the non-substituting default behaviour and avoid using
Daniel Veillardc8eab3a1999-09-04 18:27:23 +00004247entities in your XML document or data if you are not willing to handle the
4248entity references elements in the DOM tree.</p>
4249
Daniel Veillard8a469172003-06-12 16:05:07 +00004250<p>Note that at save time libxml2 enforces the conversion of the predefined
Daniel Veillardc8eab3a1999-09-04 18:27:23 +00004251entities where necessary to prevent well-formedness problems, and will also
Daniel Veillard91e9d582001-02-26 07:31:12 +00004252transparently replace those with chars (i.e. it will not generate entity
Daniel Veillard88f00ae2000-03-02 00:15:55 +00004253reference elements in the DOM tree or call the reference() SAX callback when
Daniel Veillardc8eab3a1999-09-04 18:27:23 +00004254finding them in the input).</p>
4255
Daniel Veillard7b9c4b72000-08-25 16:26:50 +00004256<p><span style="background-color: #FF0000">WARNING</span>: handling entities
Daniel Veillard8a469172003-06-12 16:05:07 +00004257on top of the libxml2 SAX interface is difficult!!! If you plan to use
Daniel Veillard63d83142002-05-20 06:51:05 +00004258non-predefined entities in your documents, then the learning curve to handle
Daniel Veillard91e9d582001-02-26 07:31:12 +00004259then using the SAX API may be long. If you plan to use complex documents, I
Daniel Veillard7b9c4b72000-08-25 16:26:50 +00004260strongly suggest you consider using the DOM interface instead and let libxml
Daniel Veillard8c6d6af2000-08-25 17:14:13 +00004261deal with the complexity rather than trying to do it yourself.</p>
Daniel Veillard7b9c4b72000-08-25 16:26:50 +00004262
Daniel Veillard2f4dfc41999-09-24 14:03:48 +00004263<h2><a name="Namespaces">Namespaces</a></h2>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +00004264
Daniel Veillard8a469172003-06-12 16:05:07 +00004265<p>The libxml2 library implements <a
Daniel Veillardec303412000-03-24 13:41:54 +00004266href="http://www.w3.org/TR/REC-xml-names/">XML namespaces</a> support by
Daniel Veillard63d83142002-05-20 06:51:05 +00004267recognizing namespace constructs in the input, and does namespace lookup
Daniel Veillardec303412000-03-24 13:41:54 +00004268automatically when building the DOM tree. A namespace declaration is
4269associated with an in-memory structure and all elements or attributes within
4270that namespace point to it. Hence testing the namespace is a simple and fast
4271equality operation at the user level.</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +00004272
Daniel Veillard8a469172003-06-12 16:05:07 +00004273<p>I suggest that people using libxml2 use a namespace, and declare it in the
Daniel Veillardf13e1ed2000-03-06 07:41:49 +00004274root element of their document as the default namespace. Then they don't need
4275to use the prefix in the content but we will have a basis for future semantic
Daniel Veillard91e9d582001-02-26 07:31:12 +00004276refinement and merging of data from different sources. This doesn't increase
Daniel Veillardec70e912001-02-26 20:10:45 +00004277the size of the XML output significantly, but significantly increases its
4278value in the long-term. Example:</p>
Daniel Veillard60979bd2000-07-10 12:17:33 +00004279<pre>&lt;mydoc xmlns="http://mydoc.example.org/schemas/"&gt;
4280 &lt;elem1&gt;...&lt;/elem1&gt;
4281 &lt;elem2&gt;...&lt;/elem2&gt;
4282&lt;/mydoc&gt;</pre>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +00004283
Daniel Veillardec70e912001-02-26 20:10:45 +00004284<p>The namespace value has to be an absolute URL, but the URL doesn't have to
4285point to any existing resource on the Web. It will bind all the element and
Daniel Veillardc0801af2002-05-28 16:28:42 +00004286attributes with that URL. I suggest to use an URL within a domain you
4287control, and that the URL should contain some kind of version information if
4288possible. For example, <code>"http://www.gnome.org/gnumeric/1.0/"</code> is a
4289good namespace scheme.</p>
Daniel Veillardec303412000-03-24 13:41:54 +00004290
4291<p>Then when you load a file, make sure that a namespace carrying the
Daniel Veillard88f00ae2000-03-02 00:15:55 +00004292version-independent prefix is installed on the root element of your document,
Daniel Veillardc8eab3a1999-09-04 18:27:23 +00004293and if the version information don't match something you know, warn the user
4294and be liberal in what you accept as the input. Also do *not* try to base
Daniel Veillard60979bd2000-07-10 12:17:33 +00004295namespace checking on the prefix value. &lt;foo:text&gt; may be exactly the
Daniel Veillard91e9d582001-02-26 07:31:12 +00004296same as &lt;bar:text&gt; in another document. What really matters is the URI
Daniel Veillard60979bd2000-07-10 12:17:33 +00004297associated with the element or the attribute, not the prefix string (which is
Daniel Veillard91e9d582001-02-26 07:31:12 +00004298just a shortcut for the full URI). In libxml, element and attributes have an
Daniel Veillardec303412000-03-24 13:41:54 +00004299<code>ns</code> field pointing to an xmlNs structure detailing the namespace
Daniel Veillard91e9d582001-02-26 07:31:12 +00004300prefix and its URI.</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +00004301
4302<p>@@Interfaces@@</p>
Daniel Veillard3e35f8e2003-10-21 00:05:38 +00004303<pre>xmlNodePtr node;
Daniel Veillardfc8dc352003-10-18 09:07:46 +00004304if(!strncmp(node-&gt;name,"mytag",5)
4305 &amp;&amp; node-&gt;ns
4306 &amp;&amp; !strcmp(node-&gt;ns-&gt;href,"http://www.mysite.com/myns/1.0")) {
4307 ...
Daniel Veillard3e35f8e2003-10-21 00:05:38 +00004308}</pre>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +00004309
Daniel Veillard91e9d582001-02-26 07:31:12 +00004310<p>Usually people object to using namespaces together with validity checking.
4311I will try to make sure that using namespaces won't break validity checking,
4312so even if you plan to use or currently are using validation I strongly
Daniel Veillardf13e1ed2000-03-06 07:41:49 +00004313suggest adding namespaces to your document. A default namespace scheme
Daniel Veillardc8eab3a1999-09-04 18:27:23 +00004314<code>xmlns="http://...."</code> should not break validity even on less
Daniel Veillard91e9d582001-02-26 07:31:12 +00004315flexible parsers. Using namespaces to mix and differentiate content coming
Daniel Veillard3e35f8e2003-10-21 00:05:38 +00004316from multiple DTDs will certainly break current validation schemes. To check
4317such documents one needs to use schema-validation, which is supported in
4318libxml2 as well. See <a href="http://www.relaxng.org/">relagx-ng</a> and <a
4319href="http://www.w3c.org/XML/Schema">w3c-schema</a>.</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +00004320
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00004321<h2><a name="Upgrading">Upgrading 1.x code</a></h2>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +00004322
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00004323<p>Incompatible changes:</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +00004324
Daniel Veillard8a469172003-06-12 16:05:07 +00004325<p>Version 2 of libxml2 is the first version introducing serious backward
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00004326incompatible changes. The main goals were:</p>
4327<ul>
4328 <li>a general cleanup. A number of mistakes inherited from the very early
4329 versions couldn't be changed due to compatibility constraints. Example
4330 the "childs" element in the nodes.</li>
4331 <li>Uniformization of the various nodes, at least for their header and link
4332 parts (doc, parent, children, prev, next), the goal is a simpler
4333 programming model and simplifying the task of the DOM implementors.</li>
4334 <li>better conformances to the XML specification, for example version 1.x
4335 had an heuristic to try to detect ignorable white spaces. As a result the
4336 SAX event generated were ignorableWhitespace() while the spec requires
4337 character() in that case. This also mean that a number of DOM node
4338 containing blank text may populate the DOM tree which were not present
4339 before.</li>
4340</ul>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +00004341
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00004342<h3>How to fix libxml-1.x code:</h3>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +00004343
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00004344<p>So client code of libxml designed to run with version 1.x may have to be
4345changed to compile against version 2.x of libxml. Here is a list of changes
4346that I have collected, they may not be sufficient, so in case you find other
Daniel Veillardfc8dc352003-10-18 09:07:46 +00004347change which are required, <a href="mailto:Daniel.Veillard@w3.org">drop me a
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00004348mail</a>:</p>
4349<ol>
4350 <li>The package name have changed from libxml to libxml2, the library name
4351 is now -lxml2 . There is a new xml2-config script which should be used to
4352 select the right parameters libxml2</li>
4353 <li>Node <strong>childs</strong> field has been renamed
4354 <strong>children</strong> so s/childs/children/g should be applied
Daniel Veillard63d83142002-05-20 06:51:05 +00004355 (probability of having "childs" anywhere else is close to 0+</li>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00004356 <li>The document don't have anymore a <strong>root</strong> element it has
4357 been replaced by <strong>children</strong> and usually you will get a
4358 list of element here. For example a Dtd element for the internal subset
4359 and it's declaration may be found in that list, as well as processing
4360 instructions or comments found before or after the document root element.
4361 Use <strong>xmlDocGetRootElement(doc)</strong> to get the root element of
Daniel Veillard63d83142002-05-20 06:51:05 +00004362 a document. Alternatively if you are sure to not reference DTDs nor have
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00004363 PIs or comments before or after the root element
4364 s/-&gt;root/-&gt;children/g will probably do it.</li>
4365 <li>The white space issue, this one is more complex, unless special case of
4366 validating parsing, the line breaks and spaces usually used for indenting
4367 and formatting the document content becomes significant. So they are
4368 reported by SAX and if your using the DOM tree, corresponding nodes are
4369 generated. Too approach can be taken:
4370 <ol>
4371 <li>lazy one, use the compatibility call
4372 <strong>xmlKeepBlanksDefault(0)</strong> but be aware that you are
4373 relying on a special (and possibly broken) set of heuristics of
4374 libxml to detect ignorable blanks. Don't complain if it breaks or
4375 make your application not 100% clean w.r.t. to it's input.</li>
Daniel Veillard63d83142002-05-20 06:51:05 +00004376 <li>the Right Way: change you code to accept possibly insignificant
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00004377 blanks characters, or have your tree populated with weird blank text
Daniel Veillard63d83142002-05-20 06:51:05 +00004378 nodes. You can spot them using the commodity function
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00004379 <strong>xmlIsBlankNode(node)</strong> returning 1 for such blank
4380 nodes.</li>
4381 </ol>
4382 <p>Note also that with the new default the output functions don't add any
4383 extra indentation when saving a tree in order to be able to round trip
4384 (read and save) without inflating the document with extra formatting
4385 chars.</p>
4386 </li>
4387 <li>The include path has changed to $prefix/libxml/ and the includes
4388 themselves uses this new prefix in includes instructions... If you are
4389 using (as expected) the
4390 <pre>xml2-config --cflags</pre>
4391 <p>output to generate you compile commands this will probably work out of
4392 the box</p>
4393 </li>
Daniel Veillard63d83142002-05-20 06:51:05 +00004394 <li>xmlDetectCharEncoding takes an extra argument indicating the length in
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00004395 byte of the head of the document available for character detection.</li>
4396</ol>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +00004397
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00004398<h3>Ensuring both libxml-1.x and libxml-2.x compatibility</h3>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +00004399
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00004400<p>Two new version of libxml (1.8.11) and libxml2 (2.3.4) have been released
Daniel Veillard63d83142002-05-20 06:51:05 +00004401to allow smooth upgrade of existing libxml v1code while retaining
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00004402compatibility. They offers the following:</p>
4403<ol>
4404 <li>similar include naming, one should use
4405 <strong>#include&lt;libxml/...&gt;</strong> in both cases.</li>
4406 <li>similar identifiers defined via macros for the child and root fields:
4407 respectively <strong>xmlChildrenNode</strong> and
4408 <strong>xmlRootNode</strong></li>
4409 <li>a new macro <strong>LIBXML_TEST_VERSION</strong> which should be
4410 inserted once in the client code</li>
4411</ol>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +00004412
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00004413<p>So the roadmap to upgrade your existing libxml applications is the
4414following:</p>
4415<ol>
4416 <li>install the libxml-1.8.8 (and libxml-devel-1.8.8) packages</li>
Daniel Veillard63d83142002-05-20 06:51:05 +00004417 <li>find all occurrences where the xmlDoc <strong>root</strong> field is
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00004418 used and change it to <strong>xmlRootNode</strong></li>
Daniel Veillardc0801af2002-05-28 16:28:42 +00004419 <li>similarly find all occurrences where the xmlNode
4420 <strong>childs</strong> field is used and change it to
4421 <strong>xmlChildrenNode</strong></li>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00004422 <li>add a <strong>LIBXML_TEST_VERSION</strong> macro somewhere in your
4423 <strong>main()</strong> or in the library init entry point</li>
4424 <li>Recompile, check compatibility, it should still work</li>
Daniel Veillardc0801af2002-05-28 16:28:42 +00004425 <li>Change your configure script to look first for xml2-config and fall
4426 back using xml-config . Use the --cflags and --libs output of the command
4427 as the Include and Linking parameters needed to use libxml.</li>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00004428 <li>install libxml2-2.3.x and libxml2-devel-2.3.x (libxml-1.8.y and
4429 libxml-devel-1.8.y can be kept simultaneously)</li>
4430 <li>remove your config.cache, relaunch your configuration mechanism, and
4431 recompile, if steps 2 and 3 were done right it should compile as-is</li>
4432 <li>Test that your application is still running correctly, if not this may
4433 be due to extra empty nodes due to formating spaces being kept in libxml2
4434 contrary to libxml1, in that case insert xmlKeepBlanksDefault(1) in your
4435 code before calling the parser (next to
4436 <strong>LIBXML_TEST_VERSION</strong> is a fine place).</li>
4437</ol>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +00004438
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00004439<p>Following those steps should work. It worked for some of my own code.</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +00004440
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00004441<p>Let me put some emphasis on the fact that there is far more changes from
4442libxml 1.x to 2.x than the ones you may have to patch for. The overall code
4443has been considerably cleaned up and the conformance to the XML specification
4444has been drastically improved too. Don't take those changes as an excuse to
4445not upgrade, it may cost a lot on the long term ...</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +00004446
Daniel Veillard52dcab32001-10-30 12:51:17 +00004447<h2><a name="Thread">Thread safety</a></h2>
4448
Daniel Veillard8a469172003-06-12 16:05:07 +00004449<p>Starting with 2.4.7, libxml2 makes provisions to ensure that concurrent
Daniel Veillard52dcab32001-10-30 12:51:17 +00004450threads can safely work in parallel parsing different documents. There is
4451however a couple of things to do to ensure it:</p>
4452<ul>
4453 <li>configure the library accordingly using the --with-threads options</li>
4454 <li>call xmlInitParser() in the "main" thread before using any of the
Daniel Veillard8a469172003-06-12 16:05:07 +00004455 libxml2 API (except possibly selecting a different memory allocator)</li>
Daniel Veillard52dcab32001-10-30 12:51:17 +00004456</ul>
4457
4458<p>Note that the thread safety cannot be ensured for multiple threads sharing
4459the same document, the locking must be done at the application level, libxml
4460exports a basic mutex and reentrant mutexes API in &lt;libxml/threads.h&gt;.
4461The parts of the library checked for thread safety are:</p>
4462<ul>
4463 <li>concurrent loading</li>
4464 <li>file access resolution</li>
4465 <li>catalog access</li>
4466 <li>catalog building</li>
4467 <li>entities lookup/accesses</li>
4468 <li>validation</li>
4469 <li>global variables per-thread override</li>
4470 <li>memory handling</li>
4471</ul>
4472
4473<p>XPath is supposed to be thread safe now, but this wasn't tested
4474seriously.</p>
4475
Daniel Veillard35008381999-10-25 13:15:52 +00004476<h2><a name="DOM"></a><a name="Principles">DOM Principles</a></h2>
Daniel Veillardb05deb71999-08-10 19:04:08 +00004477
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +00004478<p><a href="http://www.w3.org/DOM/">DOM</a> stands for the <em>Document
4479Object Model</em>; this is an API for accessing XML or HTML structured
4480documents. Native support for DOM in Gnome is on the way (module gnome-dom),
4481and will be based on gnome-xml. This will be a far cleaner interface to
4482manipulate XML files within Gnome since it won't expose the internal
4483structure.</p>
Daniel Veillard14fff061999-06-22 21:49:07 +00004484
Daniel Veillard8a469172003-06-12 16:05:07 +00004485<p>The current DOM implementation on top of libxml2 is the <a
Daniel Veillarda47fb3d2001-03-25 17:23:49 +00004486href="http://cvs.gnome.org/lxr/source/gdome2/">gdome2 Gnome module</a>, this
4487is a full DOM interface, thanks to Paolo Casarini, check the <a
4488href="http://www.cs.unibo.it/~casarini/gdome2/">Gdome2 homepage</a> for more
4489informations.</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +00004490
Daniel Veillard35008381999-10-25 13:15:52 +00004491<h2><a name="Example"></a><a name="real">A real example</a></h2>
Daniel Veillardb05deb71999-08-10 19:04:08 +00004492
4493<p>Here is a real size example, where the actual content of the application
4494data is not kept in the DOM tree but uses internal structures. It is based on
Daniel Veillard14fff061999-06-22 21:49:07 +00004495a proposal to keep a database of jobs related to Gnome, with an XML based
Daniel Veillardb05deb71999-08-10 19:04:08 +00004496storage structure. Here is an <a href="gjobs.xml">XML encoded jobs
4497base</a>:</p>
Daniel Veillard60979bd2000-07-10 12:17:33 +00004498<pre>&lt;?xml version="1.0"?&gt;
4499&lt;gjob:Helping xmlns:gjob="http://www.gnome.org/some-location"&gt;
4500 &lt;gjob:Jobs&gt;
Daniel Veillard14fff061999-06-22 21:49:07 +00004501
Daniel Veillard60979bd2000-07-10 12:17:33 +00004502 &lt;gjob:Job&gt;
4503 &lt;gjob:Project ID="3"/&gt;
4504 &lt;gjob:Application&gt;GBackup&lt;/gjob:Application&gt;
4505 &lt;gjob:Category&gt;Development&lt;/gjob:Category&gt;
Daniel Veillard14fff061999-06-22 21:49:07 +00004506
Daniel Veillard60979bd2000-07-10 12:17:33 +00004507 &lt;gjob:Update&gt;
4508 &lt;gjob:Status&gt;Open&lt;/gjob:Status&gt;
4509 &lt;gjob:Modified&gt;Mon, 07 Jun 1999 20:27:45 -0400 MET DST&lt;/gjob:Modified&gt;
4510 &lt;gjob:Salary&gt;USD 0.00&lt;/gjob:Salary&gt;
4511 &lt;/gjob:Update&gt;
Daniel Veillard14fff061999-06-22 21:49:07 +00004512
Daniel Veillard60979bd2000-07-10 12:17:33 +00004513 &lt;gjob:Developers&gt;
4514 &lt;gjob:Developer&gt;
4515 &lt;/gjob:Developer&gt;
4516 &lt;/gjob:Developers&gt;
Daniel Veillard14fff061999-06-22 21:49:07 +00004517
Daniel Veillard60979bd2000-07-10 12:17:33 +00004518 &lt;gjob:Contact&gt;
4519 &lt;gjob:Person&gt;Nathan Clemons&lt;/gjob:Person&gt;
4520 &lt;gjob:Email&gt;nathan@windsofstorm.net&lt;/gjob:Email&gt;
4521 &lt;gjob:Company&gt;
4522 &lt;/gjob:Company&gt;
4523 &lt;gjob:Organisation&gt;
4524 &lt;/gjob:Organisation&gt;
4525 &lt;gjob:Webpage&gt;
4526 &lt;/gjob:Webpage&gt;
4527 &lt;gjob:Snailmail&gt;
4528 &lt;/gjob:Snailmail&gt;
4529 &lt;gjob:Phone&gt;
4530 &lt;/gjob:Phone&gt;
4531 &lt;/gjob:Contact&gt;
Daniel Veillard14fff061999-06-22 21:49:07 +00004532
Daniel Veillard60979bd2000-07-10 12:17:33 +00004533 &lt;gjob:Requirements&gt;
Daniel Veillard14fff061999-06-22 21:49:07 +00004534 The program should be released as free software, under the GPL.
Daniel Veillard60979bd2000-07-10 12:17:33 +00004535 &lt;/gjob:Requirements&gt;
Daniel Veillard14fff061999-06-22 21:49:07 +00004536
Daniel Veillard60979bd2000-07-10 12:17:33 +00004537 &lt;gjob:Skills&gt;
4538 &lt;/gjob:Skills&gt;
Daniel Veillard14fff061999-06-22 21:49:07 +00004539
Daniel Veillard60979bd2000-07-10 12:17:33 +00004540 &lt;gjob:Details&gt;
Daniel Veillard14fff061999-06-22 21:49:07 +00004541 A GNOME based system that will allow a superuser to configure
4542 compressed and uncompressed files and/or file systems to be backed
4543 up with a supported media in the system. This should be able to
4544 perform via find commands generating a list of files that are passed
4545 to tar, dd, cpio, cp, gzip, etc., to be directed to the tape machine
4546 or via operations performed on the filesystem itself. Email
4547 notification and GUI status display very important.
Daniel Veillard60979bd2000-07-10 12:17:33 +00004548 &lt;/gjob:Details&gt;
Daniel Veillard14fff061999-06-22 21:49:07 +00004549
Daniel Veillard60979bd2000-07-10 12:17:33 +00004550 &lt;/gjob:Job&gt;
Daniel Veillard14fff061999-06-22 21:49:07 +00004551
Daniel Veillard60979bd2000-07-10 12:17:33 +00004552 &lt;/gjob:Jobs&gt;
4553&lt;/gjob:Helping&gt;</pre>
Daniel Veillardb05deb71999-08-10 19:04:08 +00004554
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +00004555<p>While loading the XML file into an internal DOM tree is a matter of
Daniel Veillard63d83142002-05-20 06:51:05 +00004556calling only a couple of functions, browsing the tree to gather the data and
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +00004557generate the internal structures is harder, and more error prone.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +00004558
4559<p>The suggested principle is to be tolerant with respect to the input
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +00004560structure. For example, the ordering of the attributes is not significant,
4561the XML specification is clear about it. It's also usually a good idea not to
Daniel Veillardec70e912001-02-26 20:10:45 +00004562depend on the order of the children of a given node, unless it really makes
4563things harder. Here is some code to parse the information for a person:</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +00004564<pre>/*
Daniel Veillard14fff061999-06-22 21:49:07 +00004565 * A person record
4566 */
4567typedef struct person {
4568 char *name;
4569 char *email;
4570 char *company;
4571 char *organisation;
4572 char *smail;
4573 char *webPage;
4574 char *phone;
4575} person, *personPtr;
4576
4577/*
4578 * And the code needed to parse it
4579 */
4580personPtr parsePerson(xmlDocPtr doc, xmlNsPtr ns, xmlNodePtr cur) {
4581 personPtr ret = NULL;
4582
4583DEBUG("parsePerson\n");
4584 /*
4585 * allocate the struct
4586 */
4587 ret = (personPtr) malloc(sizeof(person));
4588 if (ret == NULL) {
4589 fprintf(stderr,"out of memory\n");
Daniel Veillardb05deb71999-08-10 19:04:08 +00004590 return(NULL);
Daniel Veillard14fff061999-06-22 21:49:07 +00004591 }
4592 memset(ret, 0, sizeof(person));
4593
4594 /* We don't care what the top level element name is */
Daniel Veillard60979bd2000-07-10 12:17:33 +00004595 cur = cur-&gt;xmlChildrenNode;
Daniel Veillard14fff061999-06-22 21:49:07 +00004596 while (cur != NULL) {
Daniel Veillard60979bd2000-07-10 12:17:33 +00004597 if ((!strcmp(cur-&gt;name, "Person")) &amp;&amp; (cur-&gt;ns == ns))
4598 ret-&gt;name = xmlNodeListGetString(doc, cur-&gt;xmlChildrenNode, 1);
4599 if ((!strcmp(cur-&gt;name, "Email")) &amp;&amp; (cur-&gt;ns == ns))
4600 ret-&gt;email = xmlNodeListGetString(doc, cur-&gt;xmlChildrenNode, 1);
4601 cur = cur-&gt;next;
Daniel Veillard14fff061999-06-22 21:49:07 +00004602 }
4603
4604 return(ret);
Daniel Veillardb05deb71999-08-10 19:04:08 +00004605}</pre>
4606
Daniel Veillard91e9d582001-02-26 07:31:12 +00004607<p>Here are a couple of things to notice:</p>
Daniel Veillard14fff061999-06-22 21:49:07 +00004608<ul>
Daniel Veillard91e9d582001-02-26 07:31:12 +00004609 <li>Usually a recursive parsing style is the more convenient one: XML data
Daniel Veillard63d83142002-05-20 06:51:05 +00004610 is by nature subject to repetitive constructs and usually exhibits highly
4611 structured patterns.</li>
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +00004612 <li>The two arguments of type <em>xmlDocPtr</em> and <em>xmlNsPtr</em>,
4613 i.e. the pointer to the global XML document and the namespace reserved to
4614 the application. Document wide information are needed for example to
4615 decode entities and it's a good coding practice to define a namespace for
4616 your application set of data and test that the element and attributes
4617 you're analyzing actually pertains to your application space. This is
4618 done by a simple equality test (cur-&gt;ns == ns).</li>
Daniel Veillardec70e912001-02-26 20:10:45 +00004619 <li>To retrieve text and attributes value, you can use the function
4620 <em>xmlNodeListGetString</em> to gather all the text and entity reference
4621 nodes generated by the DOM output and produce an single text string.</li>
Daniel Veillard14fff061999-06-22 21:49:07 +00004622</ul>
Daniel Veillardb05deb71999-08-10 19:04:08 +00004623
4624<p>Here is another piece of code used to parse another level of the
4625structure:</p>
Daniel Veillard60979bd2000-07-10 12:17:33 +00004626<pre>#include &lt;libxml/tree.h&gt;
Daniel Veillard361d8452000-04-03 19:48:13 +00004627/*
Daniel Veillard14fff061999-06-22 21:49:07 +00004628 * a Description for a Job
4629 */
4630typedef struct job {
4631 char *projectID;
4632 char *application;
4633 char *category;
4634 personPtr contact;
4635 int nbDevelopers;
4636 personPtr developers[100]; /* using dynamic alloc is left as an exercise */
4637} job, *jobPtr;
4638
4639/*
4640 * And the code needed to parse it
4641 */
4642jobPtr parseJob(xmlDocPtr doc, xmlNsPtr ns, xmlNodePtr cur) {
4643 jobPtr ret = NULL;
4644
4645DEBUG("parseJob\n");
4646 /*
4647 * allocate the struct
4648 */
4649 ret = (jobPtr) malloc(sizeof(job));
4650 if (ret == NULL) {
4651 fprintf(stderr,"out of memory\n");
Daniel Veillardb05deb71999-08-10 19:04:08 +00004652 return(NULL);
Daniel Veillard14fff061999-06-22 21:49:07 +00004653 }
4654 memset(ret, 0, sizeof(job));
4655
4656 /* We don't care what the top level element name is */
Daniel Veillard60979bd2000-07-10 12:17:33 +00004657 cur = cur-&gt;xmlChildrenNode;
Daniel Veillard14fff061999-06-22 21:49:07 +00004658 while (cur != NULL) {
4659
Daniel Veillard60979bd2000-07-10 12:17:33 +00004660 if ((!strcmp(cur-&gt;name, "Project")) &amp;&amp; (cur-&gt;ns == ns)) {
4661 ret-&gt;projectID = xmlGetProp(cur, "ID");
4662 if (ret-&gt;projectID == NULL) {
Daniel Veillardb05deb71999-08-10 19:04:08 +00004663 fprintf(stderr, "Project has no ID\n");
4664 }
4665 }
Daniel Veillard60979bd2000-07-10 12:17:33 +00004666 if ((!strcmp(cur-&gt;name, "Application")) &amp;&amp; (cur-&gt;ns == ns))
4667 ret-&gt;application = xmlNodeListGetString(doc, cur-&gt;xmlChildrenNode, 1);
4668 if ((!strcmp(cur-&gt;name, "Category")) &amp;&amp; (cur-&gt;ns == ns))
4669 ret-&gt;category = xmlNodeListGetString(doc, cur-&gt;xmlChildrenNode, 1);
4670 if ((!strcmp(cur-&gt;name, "Contact")) &amp;&amp; (cur-&gt;ns == ns))
4671 ret-&gt;contact = parsePerson(doc, ns, cur);
4672 cur = cur-&gt;next;
Daniel Veillard14fff061999-06-22 21:49:07 +00004673 }
4674
4675 return(ret);
Daniel Veillardb05deb71999-08-10 19:04:08 +00004676}</pre>
Daniel Veillard14fff061999-06-22 21:49:07 +00004677
Daniel Veillardec70e912001-02-26 20:10:45 +00004678<p>Once you are used to it, writing this kind of code is quite simple, but
Daniel Veillard63d83142002-05-20 06:51:05 +00004679boring. Ultimately, it could be possible to write stubbers taking either C
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +00004680data structure definitions, a set of XML examples or an XML DTD and produce
4681the code needed to import and export the content between C data and XML
4682storage. This is left as an exercise to the reader :-)</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +00004683
Daniel Veillard6f0adb52000-07-03 11:41:26 +00004684<p>Feel free to use <a href="example/gjobread.c">the code for the full C
4685parsing example</a> as a template, it is also available with Makefile in the
4686Gnome CVS base under gnome-xml/example</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +00004687
Daniel Veillardc310d562000-06-23 18:32:15 +00004688<h2><a name="Contributi">Contributions</a></h2>
4689<ul>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +00004690 <li>Bjorn Reese, William Brack and Thomas Broyer have provided a number of
4691 patches, Gary Pennington worked on the validation API, threading support
4692 and Solaris port.</li>
4693 <li>John Fleck helps maintaining the documentation and man pages.</li>
Daniel Veillard7b4b2f92003-01-06 13:11:20 +00004694 <li><a href="mailto:igor@zlatkovic.com">Igor Zlatkovic</a> is now the
4695 maintainer of the Windows port, <a
4696 href="http://www.zlatkovic.com/projects/libxml/index.html">he provides
4697 binaries</a></li>
Daniel Veillardaf43f632002-03-08 15:05:20 +00004698 <li><a href="mailto:Gary.Pennington@sun.com">Gary Pennington</a> provides
4699 <a href="http://garypennington.net/libxml2/">Solaris binaries</a></li>
Daniel Veillarde356c282001-03-10 12:32:04 +00004700 <li><a
4701 href="http://mail.gnome.org/archives/xml/2001-March/msg00014.html">Matt
Daniel Veillard63d83142002-05-20 06:51:05 +00004702 Sergeant</a> developed <a
4703 href="http://axkit.org/download/">XML::LibXSLT</a>, a Perl wrapper for
Daniel Veillardaf43f632002-03-08 15:05:20 +00004704 libxml2/libxslt as part of the <a href="http://axkit.com/">AxKit XML
4705 application server</a></li>
4706 <li><a href="mailto:fnatter@gmx.net">Felix Natter</a> and <a
4707 href="mailto:geertk@ai.rug.nl">Geert Kloosterman</a> provide <a
Daniel Veillardca989762001-06-23 17:39:29 +00004708 href="libxml-doc.el">an emacs module</a> to lookup libxml(2) functions
Daniel Veillard3f6f7f62000-06-30 17:58:25 +00004709 documentation</li>
Daniel Veillardaf43f632002-03-08 15:05:20 +00004710 <li><a href="mailto:sherwin@nlm.nih.gov">Ziying Sherwin</a> provided <a
4711 href="http://xmlsoft.org/messages/0488.html">man pages</a></li>
Daniel Veillard5168dbf2001-07-07 00:18:23 +00004712 <li>there is a module for <a
4713 href="http://acs-misc.sourceforge.net/nsxml.html">libxml/libxslt support
4714 in OpenNSD/AOLServer</a></li>
Daniel Veillard2d347fa2002-03-17 10:34:11 +00004715 <li><a href="mailto:dkuhlman@cutter.rexx.com">Dave Kuhlman</a> provided the
4716 first version of libxml/libxslt <a
4717 href="http://www.rexx.com/~dkuhlman">wrappers for Python</a></li>
Daniel Veillard1aadc442001-11-28 13:10:32 +00004718 <li>Petr Kozelka provides <a
4719 href="http://sourceforge.net/projects/libxml2-pas">Pascal units to glue
4720 libxml2</a> with Kylix and Delphi and other Pascal compilers</li>
Daniel Veillard2d347fa2002-03-17 10:34:11 +00004721 <li><a href="mailto:aleksey@aleksey.com">Aleksey Sanin</a> implemented the
4722 <a href="http://www.w3.org/Signature/">XML Canonicalization and XML
4723 Digital Signature</a> <a
4724 href="http://www.aleksey.com/xmlsec/">implementations for libxml2</a></li>
Daniel Veillard17bed982003-02-24 20:11:43 +00004725 <li><a href="mailto:Steve.Ball@zveno.com">Steve Ball</a>, <a
4726 href="http://www.zveno.com/">Zveno</a> and contributors maintain <a
4727 href="http://tclxml.sourceforge.net/">tcl bindings for libxml2 and
4728 libxslt</a>, as well as <a
4729 href="http://tclxml.sf.net/tkxmllint.html">tkxmllint</a> a GUI for
4730 xmllint and <a href="http://tclxml.sf.net/tkxsltproc.html">tkxsltproc</a>
4731 a GUI for xsltproc.</li>
Daniel Veillardc310d562000-06-23 18:32:15 +00004732</ul>
4733
Daniel Veillardc8eab3a1999-09-04 18:27:23 +00004734<p></p>
Daniel Veillardccb09631998-10-27 06:21:04 +00004735</body>
4736</html>