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blob: f7035920c49074f7b5ec6969856d0712a453fdcd [file] [log] [blame]
Daniel Veillard09ab7e12001-07-10 15:49:44 +0000[diff] [blame]1<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
2 "http://www.w3.org/TR/html4/loose.dtd">
Daniel Veillardccb09631998-10-27 06:21:04 +0000[diff] [blame]3<html>
4<head>
Daniel Veillard598bec32003-07-06 10:02:03 +0000[diff] [blame]5 <title>The XML C parser and toolkit of Gnome</title>
Daniel Veillardaf43f632002-03-08 15:05:20 +0000[diff] [blame]6 <meta name="GENERATOR" content="amaya 5.1">
Daniel Veillardb24054a1999-12-18 15:32:46 +0000[diff] [blame]7 <meta http-equiv="Content-Type" content="text/html">
Daniel Veillardccb09631998-10-27 06:21:04 +0000[diff] [blame]8</head>
Daniel Veillardccb09631998-10-27 06:21:04 +0000[diff] [blame]9
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]10<body bgcolor="#ffffff">
Daniel Veillard598bec32003-07-06 10:02:03 +0000[diff] [blame]11<h1 align="center">The XML C parser and toolkit of Gnome</h1>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]12
Daniel Veillard9c466822001-10-25 12:03:39 +0000[diff] [blame]13<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 +0000[diff] [blame]16<h1 style="text-align: center">libxml, a.k.a. gnome-xml</h1>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]17
18<p></p>
Daniel Veillard9c466822001-10-25 12:03:39 +0000[diff] [blame]19
Daniel Veillard598bec32003-07-06 10:02:03 +0000[diff] [blame]20<p>Libxml2 is the XML C parser and toolkit developed for the Gnome project
Daniel Veillard23a52c52003-08-18 10:01:18 +0000[diff] [blame]21(but usable outside of the Gnome platform), it is free software available
Daniel Veillardeec1ae92003-09-09 13:11:01 +0000[diff] [blame]22under the <a href="http://www.opensource.org/licenses/mit-license.html">MIT
23License</a>. XML itself is a metalanguage to design markup languages, i.e.
24text language where semantic and structure are added to the content using
25extra "markup" information enclosed between angle brackets. HTML is the most
26well-known markup language. Though the library is written in C <a
27href="python.html">a variety of language bindings</a> make it available in
28other environments.</p>
Daniel Veillard9c466822001-10-25 12:03:39 +0000[diff] [blame]29
Daniel Veillard710823b2003-03-04 10:05:52 +0000[diff] [blame]30<p>Libxml2 is known to be very portable, the library should build and work
31without serious troubles on a variety of systems (Linux, Unix, Windows,
32CygWin, MacOS, MacOS X, RISC Os, OS/2, VMS, QNX, MVS, ...)</p>
33
Daniel Veillard9c466822001-10-25 12:03:39 +0000[diff] [blame]34<p>Libxml2 implements a number of existing standards related to markup
35languages:</p>
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]36<ul>
Daniel Veillard9c466822001-10-25 12:03:39 +0000[diff] [blame]37 <li>the XML standard: <a
38 href="http://www.w3.org/TR/REC-xml">http://www.w3.org/TR/REC-xml</a></li>
39 <li>Namespaces in XML: <a
40 href="http://www.w3.org/TR/REC-xml-names/">http://www.w3.org/TR/REC-xml-names/</a></li>
41 <li>XML Base: <a
42 href="http://www.w3.org/TR/xmlbase/">http://www.w3.org/TR/xmlbase/</a></li>
Daniel Veillardaf43f632002-03-08 15:05:20 +0000[diff] [blame]43 <li><a href="http://www.cis.ohio-state.edu/rfc/rfc2396.txt">RFC 2396</a> :
44 Uniform Resource Identifiers <a
Daniel Veillard9c466822001-10-25 12:03:39 +0000[diff] [blame]45 href="http://www.ietf.org/rfc/rfc2396.txt">http://www.ietf.org/rfc/rfc2396.txt</a></li>
46 <li>XML Path Language (XPath) 1.0: <a
47 href="http://www.w3.org/TR/xpath">http://www.w3.org/TR/xpath</a></li>
48 <li>HTML4 parser: <a
49 href="http://www.w3.org/TR/html401/">http://www.w3.org/TR/html401/</a></li>
Daniel Veillard23a52c52003-08-18 10:01:18 +0000[diff] [blame]50 <li>XML Pointer Language (XPointer) Version 1.0: <a
Daniel Veillard9c466822001-10-25 12:03:39 +0000[diff] [blame]51 href="http://www.w3.org/TR/xptr">http://www.w3.org/TR/xptr</a></li>
52 <li>XML Inclusions (XInclude) Version 1.0: <a
53 href="http://www.w3.org/TR/xinclude/">http://www.w3.org/TR/xinclude/</a></li>
Daniel Veillard23a52c52003-08-18 10:01:18 +0000[diff] [blame]54 <li>ISO-8859-x encodings, as well as <a
Daniel Veillard9c466822001-10-25 12:03:39 +0000[diff] [blame]55 href="http://www.cis.ohio-state.edu/rfc/rfc2044.txt">rfc2044</a> [UTF-8]
56 and <a href="http://www.cis.ohio-state.edu/rfc/rfc2781.txt">rfc2781</a>
Daniel Veillard23a52c52003-08-18 10:01:18 +0000[diff] [blame]57 [UTF-16] Unicode encodings, and more if using iconv support</li>
Daniel Veillard9c466822001-10-25 12:03:39 +0000[diff] [blame]58 <li>part of SGML Open Technical Resolution TR9401:1997</li>
59 <li>XML Catalogs Working Draft 06 August 2001: <a
60 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 +0000[diff] [blame]61 <li>Canonical XML Version 1.0: <a
62 href="http://www.w3.org/TR/xml-c14n">http://www.w3.org/TR/xml-c14n</a>
Daniel Veillard2d347fa2002-03-17 10:34:11 +0000[diff] [blame]63 and the Exclusive XML Canonicalization CR draft <a
64 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 +0000[diff] [blame]65 <li>Relax NG, ISO/IEC 19757-2:2003, <a
Daniel Veillard17bed982003-02-24 20:11:43 +0000[diff] [blame]66 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 +0000[diff] [blame]67 <li>W3C XML Schemas Part 2: Datatypes <a
68 href="http://www.w3.org/TR/2001/REC-xmlschema-2-20010502/">REC 02 May
Daniel Veillard7ecced52003-12-18 14:22:09 +0000[diff] [blame]69 2001</a></li>
Daniel Veillard96984452000-08-31 13:50:12 +0000[diff] [blame]70</ul>
71
Daniel Veillard560c2a42003-07-06 21:13:49 +0000[diff] [blame]72<p>In most cases libxml2 tries to implement the specifications in a
73relatively strictly compliant way. As of release 2.4.16, libxml2 passes all
741800+ tests from the <a
Daniel Veillarda5393562002-02-20 11:40:49 +0000[diff] [blame]75href="http://www.oasis-open.org/committees/xml-conformance/">OASIS XML Tests
76Suite</a>.</p>
Daniel Veillard5b16f582002-02-20 11:38:46 +0000[diff] [blame]77
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]78<p>To some extent libxml2 provides support for the following additional
79specifications but doesn't claim to implement them completely:</p>
Daniel Veillard9c466822001-10-25 12:03:39 +0000[diff] [blame]80<ul>
81 <li>Document Object Model (DOM) <a
82 href="http://www.w3.org/TR/DOM-Level-2-Core/">http://www.w3.org/TR/DOM-Level-2-Core/</a>
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]83 it doesn't implement the API itself, gdome2 does this on top of
Daniel Veillard9c466822001-10-25 12:03:39 +0000[diff] [blame]84 libxml2</li>
Daniel Veillardaf43f632002-03-08 15:05:20 +0000[diff] [blame]85 <li><a href="http://www.cis.ohio-state.edu/rfc/rfc959.txt">RFC 959</a> :
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]86 libxml2 implements a basic FTP client code</li>
Daniel Veillardaf43f632002-03-08 15:05:20 +0000[diff] [blame]87 <li><a href="http://www.cis.ohio-state.edu/rfc/rfc1945.txt">RFC 1945</a> :
88 HTTP/1.0, again a basic HTTP client code</li>
Daniel Veillard9c466822001-10-25 12:03:39 +0000[diff] [blame]89 <li>SAX: a minimal SAX implementation compatible with early expat
90 versions</li>
91 <li>DocBook SGML v4: libxml2 includes a hackish parser to transition to
92 XML</li>
93</ul>
94
Daniel Veillardf83a2c72003-04-08 13:48:40 +0000[diff] [blame]95<p>A partial implementation of <a
96href="http://www.w3.org/TR/2001/REC-xmlschema-1-20010502/">XML Schemas Part
971: Structure</a> is being worked on but it would be far too early to make any
98conformance statement about it at the moment.</p>
Daniel Veillarde6d8e202002-05-02 06:11:10 +0000[diff] [blame]99
Daniel Veillard96984452000-08-31 13:50:12 +0000[diff] [blame]100<p>Separate documents:</p>
101<ul>
Daniel Veillardaf43f632002-03-08 15:05:20 +0000[diff] [blame]102 <li><a href="http://xmlsoft.org/XSLT/">the libxslt page</a> providing an
Daniel Veillard2d347fa2002-03-17 10:34:11 +0000[diff] [blame]103 implementation of XSLT 1.0 and common extensions like EXSLT for
104 libxml2</li>
Daniel Veillardc6271d22001-10-27 07:50:58 +0000[diff] [blame]105 <li><a href="http://www.cs.unibo.it/~casarini/gdome2/">the gdome2 page</a>
Daniel Veillard2d347fa2002-03-17 10:34:11 +0000[diff] [blame]106 : a standard DOM2 implementation for libxml2</li>
107 <li><a href="http://www.aleksey.com/xmlsec/">the XMLSec page</a>: an
108 implementation of <a href="http://www.w3.org/TR/xmldsig-core/">W3C XML
109 Digital Signature</a> for libxml2</li>
Daniel Veillarde6d8e202002-05-02 06:11:10 +0000[diff] [blame]110 <li>also check the related links section below for more related and active
111 projects.</li>
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]112</ul>
113
Daniel Veillard806cada2003-03-19 21:58:59 +0000[diff] [blame]114<p>Results of the <a
115href="http://xmlbench.sourceforge.net/results/benchmark/index.html">xmlbench
116benchmark</a> on sourceforge 19 March 2003 (smaller is better):</p>
Daniel Veillardd8da01c2003-03-24 15:58:23 +0000[diff] [blame]117
118<p align="center"><img src="benchmark.gif"
119alt="benchmark results for Expat Xerces libxml2 Oracle and Sun toolkits"></p>
Daniel Veillard806cada2003-03-19 21:58:59 +0000[diff] [blame]120
Daniel Veillarde1662542002-08-28 11:50:59 +0000[diff] [blame]121<p>Logo designed by <a href="mailto:liyanage@access.ch">Marc Liyanage</a>.</p>
122
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]123<h2><a name="Introducti">Introduction</a></h2>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]124
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]125<p>This document describes libxml, the <a
Daniel Veillard560c2a42003-07-06 21:13:49 +0000[diff] [blame]126href="http://www.w3.org/XML/">XML</a> C parser and toolkit developed for the
127<a href="http://www.gnome.org/">Gnome</a> project. <a
Daniel Veillardec78c0f2000-08-25 10:25:23 +0000[diff] [blame]128href="http://www.w3.org/XML/">XML is a standard</a> for building tag-based
129structured documents/data.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]130
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]131<p>Here are some key points about libxml:</p>
132<ul>
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]133 <li>Libxml2 exports Push (progressive) and Pull (blocking) type parser
Daniel Veillard2d347fa2002-03-17 10:34:11 +0000[diff] [blame]134 interfaces for both XML and HTML.</li>
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]135 <li>Libxml2 can do DTD validation at parse time, using a parsed document
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]136 instance, or with an arbitrary DTD.</li>
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]137 <li>Libxml2 includes complete <a
Daniel Veillard8c2ecaf2001-07-10 17:53:07 +0000[diff] [blame]138 href="http://www.w3.org/TR/xpath">XPath</a>, <a
139 href="http://www.w3.org/TR/xptr">XPointer</a> and <a
140 href="http://www.w3.org/TR/xinclude">XInclude</a> implementations.</li>
Daniel Veillardec78c0f2000-08-25 10:25:23 +0000[diff] [blame]141 <li>It is written in plain C, making as few assumptions as possible, and
Daniel Veillard189446d2000-10-13 10:23:06 +0000[diff] [blame]142 sticking closely to ANSI C/POSIX for easy embedding. Works on
Daniel Veillardab8500d2000-10-15 21:06:19 +0000[diff] [blame]143 Linux/Unix/Windows, ported to a number of other platforms.</li>
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]144 <li>Basic support for HTTP and FTP client allowing applications to fetch
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]145 remote resources.</li>
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]146 <li>The design is modular, most of the extensions can be compiled out.</li>
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]147 <li>The internal document representation is as close as possible to the <a
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]148 href="http://www.w3.org/DOM/">DOM</a> interfaces.</li>
Daniel Veillard560c2a42003-07-06 21:13:49 +0000[diff] [blame]149 <li>Libxml2 also has a <a
150 href="http://www.megginson.com/SAX/index.html">SAX like interface</a>;
151 the interface is designed to be compatible with <a
Daniel Veillard402e8c82000-02-29 22:57:47 +0000[diff] [blame]152 href="http://www.jclark.com/xml/expat.html">Expat</a>.</li>
Daniel Veillardc575b992002-02-08 13:28:40 +0000[diff] [blame]153 <li>This library is released under the <a
154 href="http://www.opensource.org/licenses/mit-license.html">MIT
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]155 License</a>. See the Copyright file in the distribution for the precise
Daniel Veillardc575b992002-02-08 13:28:40 +0000[diff] [blame]156 wording.</li>
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]157</ul>
Daniel Veillardccb09631998-10-27 06:21:04 +0000[diff] [blame]158
Daniel Veillarde0c1d722001-03-21 10:28:36 +0000[diff] [blame]159<p>Warning: unless you are forced to because your application links with a
Daniel Veillard2d347fa2002-03-17 10:34:11 +0000[diff] [blame]160Gnome-1.X library requiring it, <strong><span
Daniel Veillarde0c1d722001-03-21 10:28:36 +0000[diff] [blame]161style="background-color: #FF0000">Do Not Use libxml1</span></strong>, use
162libxml2</p>
163
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]164<h2><a name="FAQ">FAQ</a></h2>
165
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]166<p>Table of Contents:</p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]167<ul>
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]168 <li><a href="FAQ.html#License">License(s)</a></li>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]169 <li><a href="FAQ.html#Installati">Installation</a></li>
170 <li><a href="FAQ.html#Compilatio">Compilation</a></li>
171 <li><a href="FAQ.html#Developer">Developer corner</a></li>
172</ul>
173
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]174<h3><a name="License">License</a>(s)</h3>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]175<ol>
176 <li><em>Licensing Terms for libxml</em>
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]177 <p>libxml2 is released under the <a
Daniel Veillardc575b992002-02-08 13:28:40 +0000[diff] [blame]178 href="http://www.opensource.org/licenses/mit-license.html">MIT
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]179 License</a>; see the file Copyright in the distribution for the precise
Daniel Veillardc575b992002-02-08 13:28:40 +0000[diff] [blame]180 wording</p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]181 </li>
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]182 <li><em>Can I embed libxml2 in a proprietary application ?</em>
Daniel Veillard42766c02002-08-22 20:52:17 +0000[diff] [blame]183 <p>Yes. The MIT License allows you to keep proprietary the changes you
184 made to libxml, but it would be graceful to send-back bug fixes and
185 improvements as patches for possible incorporation in the main
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]186 development tree.</p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]187 </li>
188</ol>
189
190<h3><a name="Installati">Installation</a></h3>
191<ol>
Daniel Veillard560c2a42003-07-06 21:13:49 +0000[diff] [blame]192 <li><strong><span style="background-color: #FF0000">Do Not Use
193 libxml1</span></strong>, use libxml2</li>
Daniel Veillardaf43f632002-03-08 15:05:20 +0000[diff] [blame]194 <li><em>Where can I get libxml</em> ?
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]195 <p>The original distribution comes from <a
196 href="ftp://rpmfind.net/pub/libxml/">rpmfind.net</a> or <a
Daniel Veillard024f1992003-12-10 16:43:49 +0000[diff] [blame]197 href="ftp://ftp.gnome.org/pub/GNOME/sources/libxml2/2.6/">gnome.org</a></p>
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]198 <p>Most Linux and BSD distributions include libxml, this is probably the
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]199 safer way for end-users to use libxml.</p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]200 <p>David Doolin provides precompiled Windows versions at <a
201 href="http://www.ce.berkeley.edu/~doolin/code/libxmlwin32/ ">http://www.ce.berkeley.edu/~doolin/code/libxmlwin32/</a></p>
202 </li>
203 <li><em>I see libxml and libxml2 releases, which one should I install ?</em>
204 <ul>
Daniel Veillard42766c02002-08-22 20:52:17 +0000[diff] [blame]205 <li>If you are not constrained by backward compatibility issues with
206 existing applications, install libxml2 only</li>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]207 <li>If you are not doing development, you can safely install both.
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]208 Usually the packages <a
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]209 href="http://rpmfind.net/linux/RPM/libxml.html">libxml</a> and <a
210 href="http://rpmfind.net/linux/RPM/libxml2.html">libxml2</a> are
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]211 compatible (this is not the case for development packages).</li>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]212 <li>If you are a developer and your system provides separate packaging
213 for shared libraries and the development components, it is possible
214 to install libxml and libxml2, and also <a
215 href="http://rpmfind.net/linux/RPM/libxml-devel.html">libxml-devel</a>
216 and <a
217 href="http://rpmfind.net/linux/RPM/libxml2-devel.html">libxml2-devel</a>
218 too for libxml2 &gt;= 2.3.0</li>
219 <li>If you are developing a new application, please develop against
220 libxml2(-devel)</li>
221 </ul>
222 </li>
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]223 <li><em>I can't install the libxml package, it conflicts with libxml0</em>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]224 <p>You probably have an old libxml0 package used to provide the shared
Daniel Veillard42766c02002-08-22 20:52:17 +0000[diff] [blame]225 library for libxml.so.0, you can probably safely remove it. The libxml
226 packages provided on <a
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]227 href="ftp://rpmfind.net/pub/libxml/">rpmfind.net</a> provide
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]228 libxml.so.0</p>
229 </li>
230 <li><em>I can't install the libxml(2) RPM package due to failed
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]231 dependencies</em>
232 <p>The most generic solution is to re-fetch the latest src.rpm , and
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]233 rebuild it locally with</p>
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]234 <p><code>rpm --rebuild libxml(2)-xxx.src.rpm</code>.</p>
Daniel Veillard42766c02002-08-22 20:52:17 +0000[diff] [blame]235 <p>If everything goes well it will generate two binary rpm packages (one
236 providing the shared libs and xmllint, and the other one, the -devel
237 package, providing includes, static libraries and scripts needed to build
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]238 applications with libxml(2)) that you can install locally.</p>
239 </li>
240</ol>
241
242<h3><a name="Compilatio">Compilation</a></h3>
243<ol>
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]244 <li><em>What is the process to compile libxml2 ?</em>
245 <p>As most UNIX libraries libxml2 follows the "standard":</p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]246 <p><code>gunzip -c xxx.tar.gz | tar xvf -</code></p>
247 <p><code>cd libxml-xxxx</code></p>
248 <p><code>./configure --help</code></p>
249 <p>to see the options, then the compilation/installation proper</p>
250 <p><code>./configure [possible options]</code></p>
251 <p><code>make</code></p>
252 <p><code>make install</code></p>
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]253 <p>At that point you may have to rerun ldconfig or a similar utility to
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]254 update your list of installed shared libs.</p>
255 </li>
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]256 <li><em>What other libraries are needed to compile/install libxml2 ?</em>
257 <p>Libxml2 does not require any other library, the normal C ANSI API
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]258 should be sufficient (please report any violation to this rule you may
259 find).</p>
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]260 <p>However if found at configuration time libxml2 will detect and use the
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]261 following libs:</p>
262 <ul>
Daniel Veillardaf43f632002-03-08 15:05:20 +0000[diff] [blame]263 <li><a href="http://www.info-zip.org/pub/infozip/zlib/">libz</a> : a
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]264 highly portable and available widely compression library.</li>
265 <li>iconv: a powerful character encoding conversion library. It is
266 included by default in recent glibc libraries, so it doesn't need to
267 be installed specifically on Linux. It now seems a <a
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]268 href="http://www.opennc.org/onlinepubs/7908799/xsh/iconv.html">part
269 of the official UNIX</a> specification. Here is one <a
Daniel Veillarddad3f682002-11-17 16:47:27 +0000[diff] [blame]270 href="http://www.gnu.org/software/libiconv/">implementation of the
271 library</a> which source can be found <a
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]272 href="ftp://ftp.ilog.fr/pub/Users/haible/gnu/">here</a>.</li>
273 </ul>
274 </li>
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]275 <li><em>Make check fails on some platforms</em>
Daniel Veillard42766c02002-08-22 20:52:17 +0000[diff] [blame]276 <p>Sometimes the regression tests' results don't completely match the
277 value produced by the parser, and the makefile uses diff to print the
278 delta. On some platforms the diff return breaks the compilation process;
279 if the diff is small this is probably not a serious problem.</p>
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]280 <p>Sometimes (especially on Solaris) make checks fail due to limitations
Daniel Veillarde46182c2002-02-12 14:29:11 +0000[diff] [blame]281 in make. Try using GNU-make instead.</p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]282 </li>
283 <li><em>I use the CVS version and there is no configure script</em>
Daniel Veillard42766c02002-08-22 20:52:17 +0000[diff] [blame]284 <p>The configure script (and other Makefiles) are generated. Use the
285 autogen.sh script to regenerate the configure script and Makefiles,
286 like:</p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]287 <p><code>./autogen.sh --prefix=/usr --disable-shared</code></p>
288 </li>
289 <li><em>I have troubles when running make tests with gcc-3.0</em>
290 <p>It seems the initial release of gcc-3.0 has a problem with the
291 optimizer which miscompiles the URI module. Please use another
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]292 compiler.</p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]293 </li>
294</ol>
295
296<h3><a name="Developer">Developer</a> corner</h3>
297<ol>
Daniel Veillard93d95252003-04-29 20:25:40 +0000[diff] [blame]298 <li><em>Troubles compiling or linking programs using libxml2</em>
299 <p>Usually the problem comes from the fact that the compiler doesn't get
300 the right compilation or linking flags. There is a small shell script
301 <code>xml2-config</code> which is installed as part of libxml2 usual
Daniel Veillard560c2a42003-07-06 21:13:49 +0000[diff] [blame]302 install process which provides those flags. Use</p>
Daniel Veillard93d95252003-04-29 20:25:40 +0000[diff] [blame]303 <p><code>xml2-config --cflags</code></p>
304 <p>to get the compilation flags and</p>
305 <p><code>xml2-config --libs</code></p>
306 <p>to get the linker flags. Usually this is done directly from the
307 Makefile as:</p>
308 <p><code>CFLAGS=`xml2-config --cflags`</code></p>
309 <p><code>LIBS=`xml2-config --libs`</code></p>
310 </li>
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]311 <li><em>xmlDocDump() generates output on one line.</em>
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]312 <p>Libxml2 will not <strong>invent</strong> spaces in the content of a
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]313 document since <strong>all spaces in the content of a document are
314 significant</strong>. If you build a tree from the API and want
315 indentation:</p>
316 <ol>
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]317 <li>the correct way is to generate those yourself too.</li>
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]318 <li>the dangerous way is to ask libxml2 to add those blanks to your
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]319 content <strong>modifying the content of your document in the
320 process</strong>. The result may not be what you expect. There is
321 <strong>NO</strong> way to guarantee that such a modification won't
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]322 affect other parts of the content of your document. See <a
Daniel Veillard5373ea12003-07-24 13:09:13 +0000[diff] [blame]323 href="http://xmlsoft.org/html/libxml-parser.html#xmlKeepBlanksDefault">xmlKeepBlanksDefault
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]324 ()</a> and <a
Daniel Veillard5373ea12003-07-24 13:09:13 +0000[diff] [blame]325 href="http://xmlsoft.org/html/libxml-tree.html#xmlSaveFormatFile">xmlSaveFormatFile
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]326 ()</a></li>
327 </ol>
328 </li>
329 <li>Extra nodes in the document:
330 <p><em>For a XML file as below:</em></p>
331 <pre>&lt;?xml version="1.0"?&gt;
332&lt;PLAN xmlns="http://www.argus.ca/autotest/1.0/"&gt;
333&lt;NODE CommFlag="0"/&gt;
334&lt;NODE CommFlag="1"/&gt;
335&lt;/PLAN&gt;</pre>
336 <p><em>after parsing it with the function
337 pxmlDoc=xmlParseFile(...);</em></p>
338 <p><em>I want to the get the content of the first node (node with the
339 CommFlag="0")</em></p>
340 <p><em>so I did it as following;</em></p>
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]341 <pre>xmlNodePtr pnode;
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]342pnode=pxmlDoc-&gt;children-&gt;children;</pre>
343 <p><em>but it does not work. If I change it to</em></p>
344 <pre>pnode=pxmlDoc-&gt;children-&gt;children-&gt;next;</pre>
345 <p><em>then it works. Can someone explain it to me.</em></p>
346 <p></p>
347 <p>In XML all characters in the content of the document are significant
348 <strong>including blanks and formatting line breaks</strong>.</p>
349 <p>The extra nodes you are wondering about are just that, text nodes with
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]350 the formatting spaces which are part of the document but that people tend
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]351 to forget. There is a function <a
352 href="http://xmlsoft.org/html/libxml-parser.html">xmlKeepBlanksDefault
353 ()</a> to remove those at parse time, but that's an heuristic, and its
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]354 use should be limited to cases where you are certain there is no
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]355 mixed-content in the document.</p>
356 </li>
357 <li><em>I get compilation errors of existing code like when accessing
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]358 <strong>root</strong> or <strong>child fields</strong> of nodes.</em>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]359 <p>You are compiling code developed for libxml version 1 and using a
360 libxml2 development environment. Either switch back to libxml v1 devel or
361 even better fix the code to compile with libxml2 (or both) by <a
362 href="upgrade.html">following the instructions</a>.</p>
363 </li>
364 <li><em>I get compilation errors about non existing
365 <strong>xmlRootNode</strong> or <strong>xmlChildrenNode</strong>
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]366 fields.</em>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]367 <p>The source code you are using has been <a
368 href="upgrade.html">upgraded</a> to be able to compile with both libxml
369 and libxml2, but you need to install a more recent version:
370 libxml(-devel) &gt;= 1.8.8 or libxml2(-devel) &gt;= 2.1.0</p>
371 </li>
372 <li><em>XPath implementation looks seriously broken</em>
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]373 <p>XPath implementation prior to 2.3.0 was really incomplete. Upgrade to
374 a recent version, there are no known bugs in the current version.</p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]375 </li>
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]376 <li><em>The example provided in the web page does not compile.</em>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]377 <p>It's hard to maintain the documentation in sync with the code
378 &lt;grin/&gt; ...</p>
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]379 <p>Check the previous points 1/ and 2/ raised before, and please send
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]380 patches.</p>
381 </li>
Daniel Veillard8d7b5c72003-11-15 18:24:36 +0000[diff] [blame]382 <li><em>Where can I get more examples and information than provided on the
Daniel Veillard42766c02002-08-22 20:52:17 +0000[diff] [blame]383 web page?</em>
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]384 <p>Ideally a libxml2 book would be nice. I have no such plan ... But you
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]385 can:</p>
386 <ul>
387 <li>check more deeply the <a href="html/libxml-lib.html">existing
388 generated doc</a></li>
Daniel Veillardc480c4e2003-12-10 13:24:38 +0000[diff] [blame]389 <li>have a look at <a href="examples/index.html">the set of
390 examples</a>.</li>
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]391 <li>look for examples of use for libxml2 function using the Gnome code.
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]392 For example the following will query the full Gnome CVS base for the
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]393 use of the <strong>xmlAddChild()</strong> function:
394 <p><a
395 href="http://cvs.gnome.org/lxr/search?string=xmlAddChild">http://cvs.gnome.org/lxr/search?string=xmlAddChild</a></p>
396 <p>This may be slow, a large hardware donation to the gnome project
397 could cure this :-)</p>
398 </li>
399 <li><a
Daniel Veillardc480c4e2003-12-10 13:24:38 +0000[diff] [blame]400 href="http://cvs.gnome.org/bonsai/rview.cgi?cvsroot=/cvs/gnome&amp;dir=gnome-xml">Browse
401 the libxml2 source</a> , I try to write code as clean and documented
Daniel Veillard42766c02002-08-22 20:52:17 +0000[diff] [blame]402 as possible, so looking at it may be helpful. In particular the code
403 of xmllint.c and of the various testXXX.c test programs should
404 provide good examples of how to do things with the library.</li>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]405 </ul>
406 </li>
407 <li>What about C++ ?
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]408 <p>libxml2 is written in pure C in order to allow easy reuse on a number
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]409 of platforms, including embedded systems. I don't intend to convert to
410 C++.</p>
Daniel Veillard91e69c52003-08-04 01:43:07 +0000[diff] [blame]411 <p>There is however a C++ wrapper which may fulfill your needs:</p>
Daniel Veillard9b6fd302002-05-13 12:06:47 +0000[diff] [blame]412 <ul>
413 <li>by Ari Johnson &lt;ari@btigate.com&gt;:
414 <p>Website: <a
Daniel Veillard91e69c52003-08-04 01:43:07 +0000[diff] [blame]415 href="http://libxmlplusplus.sourceforge.net/">http://libxmlplusplus.sourceforge.net/</a></p>
Daniel Veillard9b6fd302002-05-13 12:06:47 +0000[diff] [blame]416 <p>Download: <a
Daniel Veillard91e69c52003-08-04 01:43:07 +0000[diff] [blame]417 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 +0000[diff] [blame]418 </li>
Daniel Veillard83ee40d2003-08-09 22:24:09 +0000[diff] [blame]419 <!-- Website is currently unavailable as of 2003-08-02
Daniel Veillard9b6fd302002-05-13 12:06:47 +0000[diff] [blame]420 <li>by Peter Jones &lt;pjones@pmade.org&gt;
Daniel Veillard83ee40d2003-08-09 22:24:09 +0000[diff] [blame]421 <p>Website: <a
422 href="http://pmade.org/pjones/software/xmlwrapp/">http://pmade.org/pjones/software/xmlwrapp/</a></p>
Daniel Veillard9b6fd302002-05-13 12:06:47 +0000[diff] [blame]423 </li>
Daniel Veillard83ee40d2003-08-09 22:24:09 +0000[diff] [blame]424 -->
Daniel Veillard9b6fd302002-05-13 12:06:47 +0000[diff] [blame]425 </ul>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]426 </li>
427 <li>How to validate a document a posteriori ?
428 <p>It is possible to validate documents which had not been validated at
Daniel Veillard42766c02002-08-22 20:52:17 +0000[diff] [blame]429 initial parsing time or documents which have been built from scratch
430 using the API. Use the <a
Daniel Veillard5373ea12003-07-24 13:09:13 +0000[diff] [blame]431 href="http://xmlsoft.org/html/libxml-valid.html#xmlValidateDtd">xmlValidateDtd()</a>
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]432 function. It is also possible to simply add a DTD to an existing
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]433 document:</p>
434 <pre>xmlDocPtr doc; /* your existing document */
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]435xmlDtdPtr dtd = xmlParseDTD(NULL, filename_of_dtd); /* parse the DTD */
436
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]437 dtd-&gt;name = xmlStrDup((xmlChar*)"root_name"); /* use the given root */
438
439 doc-&gt;intSubset = dtd;
440 if (doc-&gt;children == NULL) xmlAddChild((xmlNodePtr)doc, (xmlNodePtr)dtd);
441 else xmlAddPrevSibling(doc-&gt;children, (xmlNodePtr)dtd);
442 </pre>
443 </li>
Daniel Veillarddad3f682002-11-17 16:47:27 +0000[diff] [blame]444 <li>So what is this funky "xmlChar" used all the time?
445 <p>It is a null terminated sequence of utf-8 characters. And only utf-8!
446 You need to convert strings encoded in different ways to utf-8 before
447 passing them to the API. This can be accomplished with the iconv library
448 for instance.</p>
John Fleck61f6fb62002-10-31 15:23:29 +0000[diff] [blame]449 </li>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]450 <li>etc ...</li>
451</ol>
452
453<p></p>
454
Daniel Veillard66f68e72003-08-18 16:39:51 +0000[diff] [blame]455<h2><a name="Documentat">Developer Menu</a></h2>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]456
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]457<p>There are several on-line resources related to using libxml:</p>
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]458<ol>
MST 2003 John Fleck2b7142a2003-11-22 03:55:27 +0000[diff] [blame]459 <li>Use the <a href="search.php">search engine</a> to look up
460 information.</li>
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]461 <li>Check the <a href="FAQ.html">FAQ.</a></li>
Daniel Veillardc19fccc2000-07-03 11:52:01 +0000[diff] [blame]462 <li>Check the <a href="http://xmlsoft.org/html/libxml-lib.html">extensive
MST 2003 John Fleck2b7142a2003-11-22 03:55:27 +0000[diff] [blame]463 documentation</a> automatically extracted from code comments.</li>
Daniel Veillard8d869642000-07-14 12:12:59 +0000[diff] [blame]464 <li>Look at the documentation about <a href="encoding.html">libxml
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]465 internationalization support</a>.</li>
Daniel Veillardbc66f852002-01-14 09:49:20 +0000[diff] [blame]466 <li>This page provides a global overview and <a href="example.html">some
Daniel Veillard402e8c82000-02-29 22:57:47 +0000[diff] [blame]467 examples</a> on how to use libxml.</li>
Daniel Veillardc480c4e2003-12-10 13:24:38 +0000[diff] [blame]468 <li><a href="examples/index.html">Code examples</a></li>
Daniel Veillard560c2a42003-07-06 21:13:49 +0000[diff] [blame]469 <li>John Fleck's libxml2 tutorial: <a href="tutorial/index.html">html</a>
470 or <a href="tutorial/xmltutorial.pdf">pdf</a>.</li>
Daniel Veillard1177ca42003-04-26 22:29:54 +0000[diff] [blame]471 <li>If you need to parse large files, check the <a
472 href="xmlreader.html">xmlReader</a> API tutorial</li>
Daniel Veillardaf43f632002-03-08 15:05:20 +0000[diff] [blame]473 <li><a href="mailto:james@daa.com.au">James Henstridge</a> wrote <a
Daniel Veillard402e8c82000-02-29 22:57:47 +0000[diff] [blame]474 href="http://www.daa.com.au/~james/gnome/xml-sax/xml-sax.html">some nice
475 documentation</a> explaining how to use the libxml SAX interface.</li>
Daniel Veillardc480c4e2003-12-10 13:24:38 +0000[diff] [blame]476 <li>George Lebl wrote <a
MST 2003 John Fleck2b7142a2003-11-22 03:55:27 +0000[diff] [blame]477 href="http://www-106.ibm.com/developerworks/library/l-gnome3/">an article
Daniel Veillard402e8c82000-02-29 22:57:47 +0000[diff] [blame]478 for IBM developerWorks</a> about using libxml.</li>
Daniel Veillardec303412000-03-24 13:41:54 +0000[diff] [blame]479 <li>Check <a href="http://cvs.gnome.org/lxr/source/gnome-xml/TODO">the TODO
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]480 file</a>.</li>
Daniel Veillard42766c02002-08-22 20:52:17 +0000[diff] [blame]481 <li>Read the <a href="upgrade.html">1.x to 2.x upgrade path</a>
482 description. If you are starting a new project using libxml you should
483 really use the 2.x version.</li>
Daniel Veillard845cce42002-01-09 11:51:37 +0000[diff] [blame]484 <li>And don't forget to look at the <a
485 href="http://mail.gnome.org/archives/xml/">mailing-list archive</a>.</li>
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]486</ol>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]487
Daniel Veillardd5f97f82000-09-17 16:38:14 +0000[diff] [blame]488<h2><a name="Reporting">Reporting bugs and getting help</a></h2>
Daniel Veillard4c3a2031999-11-19 17:46:26 +0000[diff] [blame]489
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]490<p>Well, bugs or missing features are always possible, and I will make a
491point of fixing them in a timely fashion. The best way to report a bug is to
Daniel Veillardccf996f2003-08-14 10:48:38 +0000[diff] [blame]492use the <a href="http://bugzilla.gnome.org/buglist.cgi?product=libxml2">Gnome
Daniel Veillard42766c02002-08-22 20:52:17 +0000[diff] [blame]493bug tracking database</a> (make sure to use the "libxml2" module name). I
494look at reports there regularly and it's good to have a reminder when a bug
495is still open. Be sure to specify that the bug is for the package libxml2.</p>
Daniel Veillard4c3a2031999-11-19 17:46:26 +0000[diff] [blame]496
Daniel Veillard4ac494b2003-09-18 15:08:00 +0000[diff] [blame]497<p>For small problems you can try to get help on IRC, the #xml channel on
498irc.gnome.org (port 6667) usually have a few person subscribed which may help
499(but there is no garantee and if a real issue is raised it should go on the
500mailing-list for archival).</p>
Daniel Veillard9582d6c2003-09-16 11:40:04 +0000[diff] [blame]501
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]502<p>There is also a mailing-list <a
Daniel Veillard3197f162001-04-04 00:40:08 +0000[diff] [blame]503href="mailto:xml@gnome.org">xml@gnome.org</a> for libxml, with an <a
504href="http://mail.gnome.org/archives/xml/">on-line archive</a> (<a
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]505href="http://xmlsoft.org/messages">old</a>). To subscribe to this list,
506please visit the <a
507href="http://mail.gnome.org/mailman/listinfo/xml">associated Web</a> page and
508follow the instructions. <strong>Do not send code, I won't debug it</strong>
509(but patches are really appreciated!).</p>
Daniel Veillard234547b2001-07-05 09:46:10 +0000[diff] [blame]510
Daniel Veillard008186f2001-09-13 14:24:44 +0000[diff] [blame]511<p>Check the following <strong><span style="color: #FF0000">before
512posting</span></strong>:</p>
Daniel Veillard234547b2001-07-05 09:46:10 +0000[diff] [blame]513<ul>
Daniel Veillard321be0c2002-10-08 21:26:42 +0000[diff] [blame]514 <li>Read the <a href="FAQ.html">FAQ</a> and <a href="search.php">use the
Daniel Veillarda37aab82003-06-09 09:10:36 +0000[diff] [blame]515 search engine</a> to get information related to your problem.</li>
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]516 <li>Make sure you are <a href="ftp://xmlsoft.org/">using a recent
517 version</a>, and that the problem still shows up in a recent version.</li>
518 <li>Check the <a href="http://mail.gnome.org/archives/xml/">list
519 archives</a> to see if the problem was reported already. In this case
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]520 there is probably a fix available, similarly check the <a
Daniel Veillardccf996f2003-08-14 10:48:38 +0000[diff] [blame]521 href="http://bugzilla.gnome.org/buglist.cgi?product=libxml2">registered
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]522 open bugs</a>.</li>
523 <li>Make sure you can reproduce the bug with xmllint or one of the test
524 programs found in source in the distribution.</li>
Daniel Veillard234547b2001-07-05 09:46:10 +0000[diff] [blame]525 <li>Please send the command showing the error as well as the input (as an
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]526 attachment)</li>
Daniel Veillard234547b2001-07-05 09:46:10 +0000[diff] [blame]527</ul>
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]528
Daniel Veillarda37aab82003-06-09 09:10:36 +0000[diff] [blame]529<p>Then send the bug with associated information to reproduce it to the <a
Daniel Veillard33a67802001-03-07 09:44:02 +0000[diff] [blame]530href="mailto:xml@gnome.org">xml@gnome.org</a> list; if it's really libxml
Daniel Veillard98d071d2003-01-10 09:22:44 +0000[diff] [blame]531related I will approve it. Please do not send mail to me directly, it makes
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]532things really hard to track and in some cases I am not the best person to
Daniel Veillard98d071d2003-01-10 09:22:44 +0000[diff] [blame]533answer a given question, ask on the list.</p>
534
535<p>To <span style="color: #E50000">be really clear about support</span>:</p>
536<ul>
Daniel Veillarda37aab82003-06-09 09:10:36 +0000[diff] [blame]537 <li>Support or help <span style="color: #E50000">requests MUST be sent to
Daniel Veillard98d071d2003-01-10 09:22:44 +0000[diff] [blame]538 the list or on bugzilla</span> in case of problems, so that the Question
539 and Answers can be shared publicly. Failing to do so carries the implicit
540 message "I want free support but I don't want to share the benefits with
Daniel Veillard831e8fd2003-01-25 11:45:34 +0000[diff] [blame]541 others" and is not welcome. I will automatically Carbon-Copy the
542 xml@gnome.org mailing list for any technical reply made about libxml2 or
543 libxslt.</li>
Daniel Veillard560c2a42003-07-06 21:13:49 +0000[diff] [blame]544 <li>There is <span style="color: #E50000">no garantee of support</span>, if
545 your question remains unanswered after a week, repost it, making sure you
546 gave all the detail needed and the information requested.</li>
Daniel Veillarda37aab82003-06-09 09:10:36 +0000[diff] [blame]547 <li>Failing to provide information as requested or double checking first
Daniel Veillard98d071d2003-01-10 09:22:44 +0000[diff] [blame]548 for prior feedback also carries the implicit message "the time of the
549 library maintainers is less valuable than my time" and might not be
550 welcome.</li>
551</ul>
Daniel Veillard4c3a2031999-11-19 17:46:26 +0000[diff] [blame]552
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]553<p>Of course, bugs reported with a suggested patch for fixing them will
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]554probably be processed faster than those without.</p>
Daniel Veillardec303412000-03-24 13:41:54 +0000[diff] [blame]555
556<p>If you're looking for help, a quick look at <a
Daniel Veillardf7ed3362001-08-17 12:01:21 +0000[diff] [blame]557href="http://mail.gnome.org/archives/xml/">the list archive</a> may actually
Daniel Veillard560c2a42003-07-06 21:13:49 +0000[diff] [blame]558provide the answer. I usually send source samples when answering libxml2
559usage questions. The <a
560href="http://xmlsoft.org/html/book1.html">auto-generated documentation</a> is
561not as polished as I would like (i need to learn more about DocBook), but
562it's a good starting point.</p>
Daniel Veillardec303412000-03-24 13:41:54 +0000[diff] [blame]563
Daniel Veillardd5f97f82000-09-17 16:38:14 +0000[diff] [blame]564<h2><a name="help">How to help</a></h2>
565
566<p>You can help the project in various ways, the best thing to do first is to
567subscribe to the mailing-list as explained before, check the <a
Daniel Veillardf7ed3362001-08-17 12:01:21 +0000[diff] [blame]568href="http://mail.gnome.org/archives/xml/">archives </a>and the <a
Daniel Veillardccf996f2003-08-14 10:48:38 +0000[diff] [blame]569href="http://bugzilla.gnome.org/buglist.cgi?product=libxml2">Gnome bug
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]570database</a>:</p>
Daniel Veillardd5f97f82000-09-17 16:38:14 +0000[diff] [blame]571<ol>
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]572 <li>Provide patches when you find problems.</li>
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]573 <li>Provide the diffs when you port libxml2 to a new platform. They may not
Daniel Veillardab8500d2000-10-15 21:06:19 +0000[diff] [blame]574 be integrated in all cases but help pinpointing portability problems
575 and</li>
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]576 <li>Provide documentation fixes (either as patches to the code comments or
Daniel Veillardd5f97f82000-09-17 16:38:14 +0000[diff] [blame]577 as HTML diffs).</li>
Daniel Veillard42766c02002-08-22 20:52:17 +0000[diff] [blame]578 <li>Provide new documentations pieces (translations, examples, etc
579 ...).</li>
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]580 <li>Check the TODO file and try to close one of the items.</li>
581 <li>Take one of the points raised in the archive or the bug database and
Daniel Veillarde7ead2d2001-08-22 23:44:09 +0000[diff] [blame]582 provide a fix. <a href="mailto:daniel@veillard.com">Get in touch with me
583 </a>before to avoid synchronization problems and check that the suggested
584 fix will fit in nicely :-)</li>
Daniel Veillardd5f97f82000-09-17 16:38:14 +0000[diff] [blame]585</ol>
586
Daniel Veillard10a2c651999-12-12 13:03:50 +0000[diff] [blame]587<h2><a name="Downloads">Downloads</a></h2>
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]588
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]589<p>The latest versions of libxml2 can be found on <a
Daniel Veillard20c8cf22001-06-26 22:47:36 +0000[diff] [blame]590href="ftp://xmlsoft.org/">xmlsoft.org</a> (<a
591href="ftp://speakeasy.rpmfind.net/pub/libxml/">Seattle</a>, <a
592href="ftp://fr.rpmfind.net/pub/libxml/">France</a>) or on the <a
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]593href="ftp://ftp.gnome.org/pub/GNOME/MIRRORS.html">Gnome FTP server</a> either
Daniel Veillard024f1992003-12-10 16:43:49 +0000[diff] [blame]594as a <a href="ftp://ftp.gnome.org/pub/GNOME/sources/libxml2/2.6/">source
MDT 2002 John Fleck30c70542002-09-24 14:24:54 +0000[diff] [blame]595archive</a><!-- commenting this out because they seem to have disappeared or <a
Daniel Veillarda41123c2001-04-22 19:31:20 +0000[diff] [blame]596href="ftp://ftp.gnome.org/pub/GNOME/stable/redhat/i386/libxml/">RPM
Daniel Veillarde16b5742002-09-26 17:50:03 +0000[diff] [blame]597packages</a> -->
Daniel Veillard321be0c2002-10-08 21:26:42 +0000[diff] [blame]598 , Antonin Sprinzl also provide <a href="ftp://gd.tuwien.ac.at/pub/libxml/">a
Daniel Veillarde16b5742002-09-26 17:50:03 +0000[diff] [blame]599mirror in Austria</a>. (NOTE that you need both the <a
Daniel Veillardc19fccc2000-07-03 11:52:01 +0000[diff] [blame]600href="http://rpmfind.net/linux/RPM/libxml2.html">libxml(2)</a> and <a
601href="http://rpmfind.net/linux/RPM/libxml2-devel.html">libxml(2)-devel</a>
Daniel Veillardb46a5732003-04-08 13:35:48 +0000[diff] [blame]602packages installed to compile applications using libxml.)</p>
603
604<p>Binary ports:</p>
605<ul>
606 <li>Red Hat RPMs for i386 are available directly on <a
607 href="ftp://xmlsoft.org/">xmlsoft.org</a>, the source RPM will compile on
608 any architecture supported by Red Hat.</li>
Daniel Veillardf83a2c72003-04-08 13:48:40 +0000[diff] [blame]609 <li><p><a href="mailto:igor@zlatkovic.com">Igor Zlatkovic</a></p>
Daniel Veillardce192eb2003-04-16 15:58:05 +0000[diff] [blame]610 is now the maintainer of the Windows port, <a
Daniel Veillardb46a5732003-04-08 13:35:48 +0000[diff] [blame]611 href="http://www.zlatkovic.com/projects/libxml/index.html">he provides
612 binaries</a>.</li>
613 <li><a href="mailto:Gary.Pennington@sun.com">Gary Pennington</a> provides
614 <a href="http://garypennington.net/libxml2/">Solaris binaries</a>.</li>
615 <li><a href="mailto:Steve.Ball@zveno.com">Steve Ball</a> provides <a
616 href="http://www.zveno.com/open_source/libxml2xslt.html">Mac Os X
617 binaries</a>.</li>
618 <li>The HP-UX porting center provides <a
619 href="http://hpux.connect.org.uk/hppd/hpux/Gnome/">HP-UX binaries</a></li>
620</ul>
621
622<p>If you know other supported binary ports, please <a
623href="http://veillard.com/">contact me</a>.</p>
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]624
Daniel Veillard6c8b1172000-03-01 00:40:41 +0000[diff] [blame]625<p><a name="Snapshot">Snapshot:</a></p>
626<ul>
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]627 <li>Code from the W3C cvs base gnome-xml <a
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]628 href="ftp://xmlsoft.org/cvs-snapshot.tar.gz">cvs-snapshot.tar.gz</a>.</li>
Daniel Veillard6c8b1172000-03-01 00:40:41 +0000[diff] [blame]629 <li>Docs, content of the web site, the list archive included <a
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]630 href="ftp://xmlsoft.org/libxml-docs.tar.gz">libxml-docs.tar.gz</a>.</li>
Daniel Veillard6c8b1172000-03-01 00:40:41 +0000[diff] [blame]631</ul>
632
Daniel Veillardc6271d22001-10-27 07:50:58 +0000[diff] [blame]633<p><a name="Contribs">Contributions:</a></p>
Daniel Veillard6c8b1172000-03-01 00:40:41 +0000[diff] [blame]634
635<p>I do accept external contributions, especially if compiling on another
Daniel Veillardc6271d22001-10-27 07:50:58 +0000[diff] [blame]636platform, get in touch with me to upload the package, wrappers for various
Daniel Veillard51095312001-10-28 18:51:57 +0000[diff] [blame]637languages have been provided, and can be found in the <a
638href="contribs.html">contrib section</a></p>
Daniel Veillard6c8b1172000-03-01 00:40:41 +0000[diff] [blame]639
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]640<p>Libxml2 is also available from CVS:</p>
Daniel Veillard10a2c651999-12-12 13:03:50 +0000[diff] [blame]641<ul>
Daniel Veillard10a2c651999-12-12 13:03:50 +0000[diff] [blame]642 <li><p>The <a
643 href="http://cvs.gnome.org/bonsai/rview.cgi?cvsroot=/cvs/gnome&amp;dir=gnome-xml">Gnome
Daniel Veillard402e8c82000-02-29 22:57:47 +0000[diff] [blame]644 CVS base</a>. Check the <a
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]645 href="http://developer.gnome.org/tools/cvs.html">Gnome CVS Tools</a>
646 page; the CVS module is <b>gnome-xml</b>.</p>
Daniel Veillard10a2c651999-12-12 13:03:50 +0000[diff] [blame]647 </li>
Daniel Veillard82687162001-01-22 15:32:01 +0000[diff] [blame]648 <li>The <strong>libxslt</strong> module is also present there</li>
Daniel Veillard10a2c651999-12-12 13:03:50 +0000[diff] [blame]649</ul>
650
651<h2><a name="News">News</a></h2>
652
Daniel Veillard944b5ff1999-12-15 19:08:24 +0000[diff] [blame]653<h3>CVS only : check the <a
654href="http://cvs.gnome.org/lxr/source/gnome-xml/ChangeLog">Changelog</a> file
Daniel Veillard189446d2000-10-13 10:23:06 +0000[diff] [blame]655for a really accurate description</h3>
Daniel Veillardab8500d2000-10-15 21:06:19 +0000[diff] [blame]656
Daniel Veillarde6d8e202002-05-02 06:11:10 +0000[diff] [blame]657<p>Items not finished and worked on, get in touch with the list if you want
658to test those</p>
Daniel Veillardab8500d2000-10-15 21:06:19 +0000[diff] [blame]659<ul>
Daniel Veillard72fef162003-02-05 14:31:19 +0000[diff] [blame]660 <li>More testing on RelaxNG</li>
Daniel Veillardcf27f7c2002-04-30 07:12:39 +0000[diff] [blame]661 <li>Finishing up <a href="http://www.w3.org/TR/xmlschema-1/">XML
Daniel Veillard72fef162003-02-05 14:31:19 +0000[diff] [blame]662 Schemas</a></li>
663</ul>
664
Daniel Veillard189f46b2004-01-25 21:03:04 +0000[diff] [blame^]665<h3>2.6.5: Jan 25 2004</h3>
666<ul>
667 <li>Bugfixes: dictionnaries for schemas (William Brack), regexp segfault
668 (William), xs:all problem (William), a number of XPointer bugfixes
669 (William), xmllint error go to stderr, DTD validation problem with
670 namespace, memory leak (William), SAX1 cleanup and minimal options fixes
671 (Mark Vadoc), parser context reset on error (Shaun McCance), XPath union
672 evaluation problem (William) , xmlReallocLoc with NULL (Aleksey Sanin),
673 XML Schemas double free (Steve Ball), XInclude with no href, argument
674 callbacks order for XPath callbacks (Frederic Peters)</li>
675 <li>Documentation: python scripts (William Brack), xslt stylesheets (John
676 Fleck), doc (Sven Zimmerman), I/O example.</li>
677 <li>Python bindings: fixes (William), enum support (Stéphane Bidoul),
678 structured error reporting (Stéphane Bidoul)</li>
679 <li>XInclude: various fixes for conformance, problem related to dictionnary
680 references (William &amp; me), recursion (William)</li>
681 <li>xmlWriter: indentation (Lucas Brasilino), memory leaks (Alfred
682 Mickautsch), </li>
683 <li>xmlSchemas: normalizedString datatype (John Belmonte)</li>
684 <li>code cleanup for strings functions (William)</li>
685 <li>Windows: compiler patches (Mark Vakoc)</li>
686 <li>Parser optimizations, a few new XPath and dictionnary APIs for future
687 XSLT optimizations.</li>
688</ul>
689
Daniel Veillarde6e59cd2003-12-24 11:56:44 +0000[diff] [blame]690<h3>2.6.4: Dec 24 2003</h3>
691<ul>
692 <li>Windows build fixes (Igor Zlatkovic)</li>
Daniel Veillard189f46b2004-01-25 21:03:04 +0000[diff] [blame^]693 <li>Some serious XInclude problems reported by Oleg Paraschenko and</li>
694 <li>Unix and Makefile packaging fixes (me, William Brack,</li>
Daniel Veillarde6e59cd2003-12-24 11:56:44 +0000[diff] [blame]695 <li>Documentation improvements (John Fleck, William Brack), example fix
696 (Lucas Brasilino)</li>
697 <li>bugfixes: xmlTextReaderExpand() with xmlReaderWalker, XPath handling of
698 NULL strings (William Brack) , API building reader or parser from
699 filedescriptor should not close it, changed XPath sorting to be stable
700 again (William Brack), xmlGetNodePath() generating '(null)' (William
701 Brack), DTD validation and namespace bug (William Brack), XML Schemas
702 double inclusion behaviour</li>
703</ul>
704
Daniel Veillardc480c4e2003-12-10 13:24:38 +0000[diff] [blame]705<h3>2.6.3: Dec 10 2003</h3>
706<ul>
707 <li>documentation updates and cleanup (DV, William Brack, John Fleck)</li>
708 <li>added a repository of examples, examples from Aleksey Sanin, Dodji
Daniel Veillarde6e59cd2003-12-24 11:56:44 +0000[diff] [blame]709 Seketeli, Alfred Mickautsch</li>
Daniel Veillardc480c4e2003-12-10 13:24:38 +0000[diff] [blame]710 <li>Windows updates: Mark Vakoc, Igor Zlatkovic, Eric Zurcher, Mingw
711 (Kenneth Haley)</li>
712 <li>Unicode range checking (William Brack)</li>
713 <li>code cleanup (William Brack)</li>
714 <li>Python bindings: doc (John Fleck), bug fixes</li>
715 <li>UTF-16 cleanup and BOM issues (William Brack)</li>
716 <li>bug fixes: ID and xmlReader validation, XPath (William Brack),
717 xmlWriter (Alfred Mickautsch), hash.h inclusion problem, HTML parser
718 (James Bursa), attribute defaulting and validation, some serialization
719 cleanups, XML_GET_LINE macro, memory debug when using threads (William
720 Brack), serialization of attributes and entities content, xmlWriter
721 (Daniel Schulman)</li>
722 <li>XInclude bugfix, new APIs and update to the last version including the
723 namespace change.</li>
724 <li>XML Schemas improvements: include (Robert Stepanek), import and
725 namespace handling, fixed the regression tests troubles, added examples
Daniel Veillarde6e59cd2003-12-24 11:56:44 +0000[diff] [blame]726 based on Eric van der Vlist book, regexp fixes</li>
Daniel Veillardc480c4e2003-12-10 13:24:38 +0000[diff] [blame]727 <li>preliminary pattern support for streaming (needed for schemas
728 constraints), added xmlTextReaderPreservePattern() to collect subdocument
729 when streaming.</li>
730 <li>various fixes in the structured error handling</li>
731</ul>
732
Daniel Veillard6d373a22003-11-04 10:26:43 +0000[diff] [blame]733<h3>2.6.2: Nov 4 2003</h3>
734<ul>
735 <li>XPath context unregistration fixes</li>
736 <li>text node coalescing fixes (Mark Lilback)</li>
737 <li>API to screate a W3C Schemas from an existing document (Steve Ball)</li>
738 <li>BeOS patches (Marcin 'Shard' Konicki)</li>
739 <li>xmlStrVPrintf function added (Aleksey Sanin)</li>
740 <li>compilation fixes (Mark Vakoc)</li>
741 <li>stdin parsing fix (William Brack)</li>
742 <li>a posteriori DTD validation fixes</li>
Daniel Veillardc480c4e2003-12-10 13:24:38 +0000[diff] [blame]743 <li>xmlReader bug fixes: Walker fixes, python bindings</li>
Daniel Veillard6d373a22003-11-04 10:26:43 +0000[diff] [blame]744 <li>fixed xmlStopParser() to really stop the parser and errors</li>
745 <li>always generate line numbers when using the new xmlReadxxx
746 functions</li>
747 <li>added XInclude support to the xmlReader interface</li>
748 <li>implemented XML_PARSE_NONET parser option</li>
749 <li>DocBook XSLT processing bug fixed</li>
750 <li>HTML serialization for &lt;p&gt; elements (William Brack and me)</li>
751 <li>XPointer failure in XInclude are now handled as resource errors</li>
752 <li>fixed xmllint --html to use the HTML serializer on output (added
753 --xmlout to implement the previous behaviour of saving it using the XML
754 serializer)</li>
755</ul>
756
Daniel Veillarde4e3f5d2003-10-28 23:06:32 +0000[diff] [blame]757<h3>2.6.1: Oct 28 2003</h3>
758<ul>
759 <li>Mostly bugfixes after the big 2.6.0 changes</li>
760 <li>Unix compilation patches: libxml.m4 (Patrick Welche), warnings cleanup
761 (William Brack)</li>
762 <li>Windows compilation patches (Joachim Bauch, Stephane Bidoul, Igor
763 Zlatkovic)</li>
764 <li>xmlWriter bugfix (Alfred Mickautsch)</li>
765 <li>chvalid.[ch]: couple of fixes from Stephane Bidoul</li>
Daniel Veillard6d373a22003-11-04 10:26:43 +0000[diff] [blame]766 <li>context reset: error state reset, push parser reset (Graham
767 Bennett)</li>
Daniel Veillarde4e3f5d2003-10-28 23:06:32 +0000[diff] [blame]768 <li>context reuse: generate errors if file is not readable</li>
769 <li>defaulted attributes for element coming from internal entities
770 (Stephane Bidoul)</li>
771 <li>Python: tab and spaces mix (William Brack)</li>
772 <li>Error handler could crash in DTD validation in 2.6.0</li>
773 <li>xmlReader: do not use the document or element _private field</li>
774 <li>testSAX.c: avoid a problem with some PIs (Massimo Morara)</li>
775 <li>general bug fixes: mandatory encoding in text decl, serializing
776 Document Fragment nodes, xmlSearchNs 2.6.0 problem (Kasimier Buchcik),
777 XPath errors not reported, slow HTML parsing of large documents.</li>
778</ul>
779
Daniel Veillard3e35f8e2003-10-21 00:05:38 +0000[diff] [blame]780<h3>2.6.0: Oct 20 2003</h3>
781<ul>
782 <li>Major revision release: should be API and ABI compatible but got a lot
783 of change</li>
784 <li>Increased the library modularity, far more options can be stripped out,
785 a --with-minimum configuration will weight around 160KBytes</li>
786 <li>Use per parser and per document dictionnary, allocate names and small
787 text nodes from the dictionnary</li>
788 <li>Switch to a SAX2 like parser rewrote most of the XML parser core,
789 provides namespace resolution and defaulted attributes, minimize memory
790 allocations and copies, namespace checking and specific error handling,
791 immutable buffers, make predefined entities static structures, etc...</li>
792 <li>rewrote all the error handling in the library, all errors can be
793 intercepted at a structured level, with precise information
794 available.</li>
795 <li>New simpler and more generic XML and HTML parser APIs, allowing to
796 easilly modify the parsing options and reuse parser context for multiple
797 consecutive documents.</li>
798 <li>Similar new APIs for the xmlReader, for options and reuse, provided new
799 functions to access content as const strings, use them for Python
800 bindings</li>
801 <li>a lot of other smaller API improvements: xmlStrPrintf (Aleksey Sanin),
802 Walker i.e. reader on a document tree based on Alfred Mickautsch code,
803 make room in nodes for line numbers, reference counting and future PSVI
804 extensions, generation of character ranges to be checked with faster
805 algorithm (William), xmlParserMaxDepth (Crutcher Dunnavant), buffer
806 access</li>
807 <li>New xmlWriter API provided by Alfred Mickautsch</li>
808 <li>Schemas: base64 support by Anthony Carrico</li>
809 <li>Parser&lt;-&gt;HTTP integration fix, proper processing of the Mime-Type
810 and charset informations if available.</li>
811 <li>Relax-NG: bug fixes including the one reported by Martijn Faassen and
812 zeroOrMore, better error reporting.</li>
813 <li>Python bindings (Stéphane Bidoul), never use stdout for errors
814 output</li>
815 <li>Portability: all the headers have macros for export and calling
816 convention definitions (Igor Zlatkovic), VMS update (Craig A. Berry),
817 Windows: threads (Jesse Pelton), Borland compiler (Eric Zurcher, Igor),
818 Mingw (Igor), typos (Mark Vakoc), beta version (Stephane Bidoul),
819 warning cleanups on AIX and MIPS compilers (William Brack), BeOS (Marcin
820 'Shard' Konicki)</li>
821 <li>Documentation fixes and README (William Brack), search fix (William),
822 tutorial updates (John Fleck), namespace docs (Stefan Kost)</li>
823 <li>Bug fixes: xmlCleanupParser (Dave Beckett), threading uninitialized
824 mutexes, HTML doctype lowercase, SAX/IO (William), compression detection
825 and restore (William), attribute declaration in DTDs (William), namespace
826 on attribute in HTML output (William), input filename (Rob Richards),
827 namespace DTD validation, xmlReplaceNode (Chris Ryland), I/O callbacks
828 (Markus Keim), CDATA serialization (Shaun McCance), xmlReader (Peter
829 Derr), high codepoint charref like &amp;#x10FFFF;, buffer access in push
830 mode (Justin Fletcher), TLS threads on Windows (Jesse Pelton), XPath bug
831 (William), xmlCleanupParser (Marc Liyanage), CDATA output (William), HTTP
832 error handling.</li>
833 <li>xmllint options: --dtdvalidfpi for Tobias Reif, --sax1 for compat
834 testing, --nodict for building without tree dictionnary, --nocdata to
835 replace CDATA by text, --nsclean to remove surperfluous namespace
836 declarations</li>
837 <li>added xml2-config --libtool-libs option from Kevin P. Fleming</li>
838 <li>a lot of profiling and tuning of the code, speedup patch for
839 xmlSearchNs() by Luca Padovani. The xmlReader should do far less
840 allocation and it speed should get closer to SAX. Chris Anderson worked
841 on speeding and cleaning up repetitive checking code.</li>
842 <li>cleanup of "make tests"</li>
843 <li>libxml-2.0-uninstalled.pc from Malcolm Tredinnick</li>
844 <li>deactivated the broken docBook SGML parser code and plugged the XML
845 parser instead.</li>
846</ul>
847
Daniel Veillardeec1ae92003-09-09 13:11:01 +0000[diff] [blame]848<h3>2.5.11: Sep 9 2003</h3>
849
850<p>A bugfix only release:</p>
851<ul>
852 <li>risk of crash in Relax-NG</li>
853 <li>risk of crash when using multithreaded programs</li>
854</ul>
855
Daniel Veillardcfba2fe2003-08-15 00:33:43 +0000[diff] [blame]856<h3>2.5.10: Aug 15 2003</h3>
857
858<p>A bugfixes only release</p>
859<ul>
860 <li>Windows Makefiles (William Brack)</li>
861 <li>UTF-16 support fixes (Mark Itzcovitz)</li>
862 <li>Makefile and portability (William Brack) automake, Linux alpha, Mingw
Daniel Veillardeec1ae92003-09-09 13:11:01 +0000[diff] [blame]863 on Windows (Mikhail Grushinskiy)</li>
Daniel Veillardcfba2fe2003-08-15 00:33:43 +0000[diff] [blame]864 <li>HTML parser (Oliver Stoeneberg)</li>
865 <li>XInclude performance problem reported by Kevin Ruscoe</li>
866 <li>XML parser performance problem reported by Grant Goodale</li>
867 <li>xmlSAXParseDTD() bug fix from Malcolm Tredinnick</li>
Daniel Veillardeec1ae92003-09-09 13:11:01 +0000[diff] [blame]868 <li>and a couple other cleanup</li>
Daniel Veillardcfba2fe2003-08-15 00:33:43 +0000[diff] [blame]869</ul>
870
Daniel Veillard83ee40d2003-08-09 22:24:09 +0000[diff] [blame]871<h3>2.5.9: Aug 9 2003</h3>
872<ul>
873 <li>bugfixes: IPv6 portability, xmlHasNsProp (Markus Keim), Windows build
874 (Wiliam Brake, Jesse Pelton, Igor), Schemas (Peter Sobisch), threading
875 (Rob Richards), hexBinary type (), UTF-16 BOM (Dodji Seketeli),
876 xmlReader, Relax-NG schemas compilation, namespace handling, EXSLT (Sean
877 Griffin), HTML parsing problem (William Brack), DTD validation for mixed
878 content + namespaces, HTML serialization, library initialization,
879 progressive HTML parser</li>
880 <li>better interfaces for Relax-NG error handling (Joachim Bauch, )</li>
881 <li>adding xmlXIncludeProcessTree() for XInclud'ing in a subtree</li>
882 <li>doc fixes and improvements (John Fleck)</li>
883 <li>configure flag for -with-fexceptions when embedding in C++</li>
884 <li>couple of new UTF-8 helper functions (William Brack)</li>
885 <li>general encoding cleanup + ISO-8859-x without iconv (Peter Jacobi)</li>
886 <li>xmlTextReader cleanup + enum for node types (Bjorn Reese)</li>
887 <li>general compilation/warning cleanup Solaris/HP-UX/... (William
888 Brack)</li>
889</ul>
890
Daniel Veillard560c2a42003-07-06 21:13:49 +0000[diff] [blame]891<h3>2.5.8: Jul 6 2003</h3>
892<ul>
893 <li>bugfixes: XPath, XInclude, file/URI mapping, UTF-16 save (Mark
894 Itzcovitz), UTF-8 checking, URI saving, error printing (William Brack),
895 PI related memleak, compilation without schemas or without xpath (Joerg
896 Schmitz-Linneweber/Garry Pennington), xmlUnlinkNode problem with DTDs,
897 rpm problem on , i86_64, removed a few compilation problems from 2.5.7,
898 xmlIOParseDTD, and xmlSAXParseDTD (Malcolm Tredinnick)</li>
899 <li>portability: DJGPP (MsDos) , OpenVMS (Craig A. Berry)</li>
900 <li>William Brack fixed multithreading lock problems</li>
901 <li>IPv6 patch for FTP and HTTP accesses (Archana Shah/Wipro)</li>
902 <li>Windows fixes (Igor Zlatkovic, Eric Zurcher), threading (Stéphane
903 Bidoul)</li>
904 <li>A few W3C Schemas Structure improvements</li>
905 <li>W3C Schemas Datatype improvements (Charlie Bozeman)</li>
906 <li>Python bindings for thread globals (Stéphane Bidoul), and method/class
Daniel Veillard83ee40d2003-08-09 22:24:09 +0000[diff] [blame]907 generator</li>
908 <li>added --nonet option to xmllint</li>
Daniel Veillard560c2a42003-07-06 21:13:49 +0000[diff] [blame]909 <li>documentation improvements (John Fleck)</li>
910</ul>
911
Daniel Veillard92fc02c2003-04-24 23:12:35 +0000[diff] [blame]912<h3>2.5.7: Apr 25 2003</h3>
913<ul>
914 <li>Relax-NG: Compiling to regexp and streaming validation on top of the
915 xmlReader interface, added to xmllint --stream</li>
916 <li>xmlReader: Expand(), Next() and DOM access glue, bug fixes</li>
917 <li>Support for large files: RGN validated a 4.5GB instance</li>
918 <li>Thread support is now configured in by default</li>
919 <li>Fixes: update of the Trio code (Bjorn), WXS Date and Duration fixes
920 (Charles Bozeman), DTD and namespaces (Brent Hendricks), HTML push parser
921 and zero bytes handling, some missing Windows file path conversions,
922 behaviour of the parser and validator in the presence of "out of memory"
Daniel Veillard93d95252003-04-29 20:25:40 +0000[diff] [blame]923 error conditions</li>
Daniel Veillard92fc02c2003-04-24 23:12:35 +0000[diff] [blame]924 <li>extended the API to be able to plug a garbage collecting memory
925 allocator, added xmlMallocAtomic() and modified the allocations
926 accordingly.</li>
927 <li>Performances: removed excessive malloc() calls, speedup of the push and
928 xmlReader interfaces, removed excessive thread locking</li>
929 <li>Documentation: man page (John Fleck), xmlReader documentation</li>
930 <li>Python: adding binding for xmlCatalogAddLocal (Brent M Hendricks)</li>
931</ul>
932
Daniel Veillardc2d4a932003-04-01 11:13:05 +0000[diff] [blame]933<h3>2.5.6: Apr 1 2003</h3>
934<ul>
935 <li>Fixed W3C XML Schemas datatype, should be compliant now except for
936 binHex and base64 which are not supported yet.</li>
937 <li>bug fixes: non-ASCII IDs, HTML output, XInclude on large docs and
938 XInclude entities handling, encoding detection on external subsets, XML
939 Schemas bugs and memory leaks, HTML parser (James Bursa)</li>
940 <li>portability: python/trio (Albert Chin), Sun compiler warnings</li>
941 <li>documentation: added --relaxng option to xmllint man page (John)</li>
942 <li>improved error reporting: xml:space, start/end tag mismatches, Relax NG
943 errors</li>
944</ul>
945
946<h3>2.5.5: Mar 24 2003</h3>
Daniel Veillardd8da01c2003-03-24 15:58:23 +0000[diff] [blame]947<ul>
948 <li>Lot of fixes on the Relax NG implementation. More testing including
949 DocBook and TEI examples.</li>
950 <li>Increased the support for W3C XML Schemas datatype</li>
951 <li>Several bug fixes in the URI handling layer</li>
952 <li>Bug fixes: HTML parser, xmlReader, DTD validation, XPath, encoding
953 conversion, line counting in the parser.</li>
954 <li>Added support for $XMLLINT_INDENT environment variable, FTP delete</li>
955 <li>Fixed the RPM spec file name</li>
956</ul>
957
Daniel Veillard17bed982003-02-24 20:11:43 +0000[diff] [blame]958<h3>2.5.4: Feb 20 2003</h3>
959<ul>
960 <li>Conformance testing and lot of fixes on Relax NG and XInclude
961 implementation</li>
962 <li>Implementation of XPointer element() scheme</li>
963 <li>Bug fixes: XML parser, XInclude entities merge, validity checking on
964 namespaces,
965 <p>2 serialization bugs, node info generation problems, a DTD regexp
966 generation problem.</p>
967 </li>
968 <li>Portability: windows updates and path canonicalization (Igor)</li>
969 <li>A few typo fixes (Kjartan Maraas)</li>
970 <li>Python bindings generator fixes (Stephane Bidoul)</li>
971</ul>
972
Daniel Veillard1d788d22003-02-10 16:21:58 +0000[diff] [blame]973<h3>2.5.3: Feb 10 2003</h3>
974<ul>
975 <li>RelaxNG and XML Schemas datatypes improvements, and added a first
976 version of RelaxNG Python bindings</li>
977 <li>Fixes: XLink (Sean Chittenden), XInclude (Sean Chittenden), API fix for
978 serializing namespace nodes, encoding conversion bug, XHTML1
979 serialization</li>
980 <li>Portability fixes: Windows (Igor), AMD 64bits RPM spec file</li>
981</ul>
982
Daniel Veillard72fef162003-02-05 14:31:19 +0000[diff] [blame]983<h3>2.5.2: Feb 5 2003</h3>
984<ul>
985 <li>First implementation of RelaxNG, added --relaxng flag to xmllint</li>
986 <li>Schemas support now compiled in by default.</li>
987 <li>Bug fixes: DTD validation, namespace checking, XInclude and entities,
988 delegateURI in XML Catalogs, HTML parser, XML reader (Stéphane Bidoul),
989 XPath parser and evaluation, UTF8ToUTF8 serialization, XML reader memory
990 consumption, HTML parser, HTML serialization in the presence of
991 namespaces</li>
992 <li>added an HTML API to check elements and attributes.</li>
993 <li>Documentation improvement, PDF for the tutorial (John Fleck), doc
994 patches (Stefan Kost)</li>
995 <li>Portability fixes: NetBSD (Julio Merino), Windows (Igor Zlatkovic)</li>
996 <li>Added python bindings for XPointer, contextual error reporting
997 (Stéphane Bidoul)</li>
998 <li>URI/file escaping problems (Stefano Zacchiroli)</li>
Daniel Veillardcf27f7c2002-04-30 07:12:39 +0000[diff] [blame]999</ul>
1000
Daniel Veillarde2830f12003-01-08 17:47:49 +0000[diff] [blame]1001<h3>2.5.1: Jan 8 2003</h3>
1002<ul>
1003 <li>Fixes a memory leak and configuration/compilation problems in 2.5.0</li>
1004 <li>documentation updates (John)</li>
1005 <li>a couple of XmlTextReader fixes</li>
1006</ul>
1007
Daniel Veillard7b4b2f92003-01-06 13:11:20 +0000[diff] [blame]1008<h3>2.5.0: Jan 6 2003</h3>
1009<ul>
1010 <li>New <a href="xmlreader.html">XmltextReader interface</a> based on C#
1011 API (with help of Stéphane Bidoul)</li>
1012 <li>Windows: more exports, including the new API (Igor)</li>
1013 <li>XInclude fallback fix</li>
1014 <li>Python: bindings for the new API, packaging (Stéphane Bidoul),
1015 drv_libxml2.py Python xml.sax driver (Stéphane Bidoul), fixes, speedup
1016 and iterators for Python-2.2 (Hannu Krosing)</li>
1017 <li>Tutorial fixes (john Fleck and Niraj Tolia) xmllint man update
1018 (John)</li>
1019 <li>Fix an XML parser bug raised by Vyacheslav Pindyura</li>
1020 <li>Fix for VMS serialization (Nigel Hall) and config (Craig A. Berry)</li>
1021 <li>Entities handling fixes</li>
1022 <li>new API to optionally track node creation and deletion (Lukas
1023 Schroeder)</li>
1024 <li>Added documentation for the XmltextReader interface and some <a
1025 href="guidelines.html">XML guidelines</a></li>
1026</ul>
1027
Daniel Veillardc1eed322002-12-12 11:01:32 +0000[diff] [blame]1028<h3>2.4.30: Dec 12 2002</h3>
1029<ul>
1030 <li>2.4.29 broke the python bindings, rereleasing</li>
1031 <li>Improvement/fixes of the XML API generator, and couple of minor code
1032 fixes.</li>
1033</ul>
1034
Daniel Veillard9b4bb4d2002-12-11 19:28:47 +0000[diff] [blame]1035<h3>2.4.29: Dec 11 2002</h3>
1036<ul>
1037 <li>Windows fixes (Igor): Windows CE port, pthread linking, python bindings
1038 (Stéphane Bidoul), Mingw (Magnus Henoch), and export list updates</li>
1039 <li>Fix for prev in python bindings (ERDI Gergo)</li>
1040 <li>Fix for entities handling (Marcus Clarke)</li>
1041 <li>Refactored the XML and HTML dumps to a single code path, fixed XHTML1
1042 dump</li>
1043 <li>Fix for URI parsing when handling URNs with fragment identifiers</li>
1044 <li>Fix for HTTP URL escaping problem</li>
1045 <li>added an TextXmlReader (C#) like API (work in progress)</li>
1046 <li>Rewrote the API in XML generation script, includes a C parser and saves
1047 more informations needed for C# bindings</li>
1048</ul>
1049
Daniel Veillardf9c4cad2002-11-22 15:57:07 +0000[diff] [blame]1050<h3>2.4.28: Nov 22 2002</h3>
1051<ul>
1052 <li>a couple of python binding fixes</li>
1053 <li>2 bug fixes in the XML push parser</li>
1054 <li>potential memory leak removed (Martin Stoilov)</li>
1055 <li>fix to the configure script for Unix (Dimitri Papadopoulos)</li>
1056 <li>added encoding support for XInclude parse="text"</li>
1057 <li>autodetection of XHTML1 and specific serialization rules added</li>
Daniel Veillard9b4bb4d2002-12-11 19:28:47 +0000[diff] [blame]1058 <li>nasty threading bug fixed (William Brack)</li>
Daniel Veillardf9c4cad2002-11-22 15:57:07 +0000[diff] [blame]1059</ul>
1060
Daniel Veillarddad3f682002-11-17 16:47:27 +0000[diff] [blame]1061<h3>2.4.27: Nov 17 2002</h3>
1062<ul>
1063 <li>fixes for the Python bindings</li>
1064 <li>a number of bug fixes: SGML catalogs, xmlParseBalancedChunkMemory(),
1065 HTML parser, Schemas (Charles Bozeman), document fragment support
1066 (Christian Glahn), xmlReconciliateNs (Brian Stafford), XPointer,
1067 xmlFreeNode(), xmlSAXParseMemory (Peter Jones), xmlGetNodePath (Petr
1068 Pajas), entities processing</li>
1069 <li>added grep to xmllint --shell</li>
1070 <li>VMS update patch from Craig A. Berry</li>
1071 <li>cleanup of the Windows build with support for more compilers (Igor),
1072 better thread support on Windows</li>
1073 <li>cleanup of Unix Makefiles and spec file</li>
1074 <li>Improvements to the documentation (John Fleck)</li>
1075</ul>
1076
Daniel Veillard48267432002-10-18 11:21:38 +0000[diff] [blame]1077<h3>2.4.26: Oct 18 2002</h3>
1078<ul>
1079 <li>Patches for Windows CE port, improvements on Windows paths handling</li>
1080 <li>Fixes to the validation code (DTD and Schemas), xmlNodeGetPath() ,
1081 HTML serialization, Namespace compliance, and a number of small
1082 problems</li>
1083</ul>
1084
Daniel Veillarde16b5742002-09-26 17:50:03 +0000[diff] [blame]1085<h3>2.4.25: Sep 26 2002</h3>
1086<ul>
1087 <li>A number of bug fixes: XPath, validation, Python bindings, DOM and
1088 tree, xmlI/O, Html</li>
1089 <li>Serious rewrite of XInclude</li>
1090 <li>Made XML Schemas regexp part of the default build and APIs, small fix
1091 and improvement of the regexp core</li>
1092 <li>Changed the validation code to reuse XML Schemas regexp APIs</li>
1093 <li>Better handling of Windows file paths, improvement of Makefiles (Igor,
1094 Daniel Gehriger, Mark Vakoc)</li>
1095 <li>Improved the python I/O bindings, the tests, added resolver and regexp
Daniel Veillard321be0c2002-10-08 21:26:42 +0000[diff] [blame]1096 APIs</li>
Daniel Veillarde16b5742002-09-26 17:50:03 +0000[diff] [blame]1097 <li>New logos from Marc Liyanage</li>
1098 <li>Tutorial improvements: John Fleck, Christopher Harris</li>
1099 <li>Makefile: Fixes for AMD x86_64 (Mandrake), DESTDIR (Christophe
1100 Merlet)</li>
1101 <li>removal of all stderr/perror use for error reporting</li>
1102 <li>Better error reporting: XPath and DTD validation</li>
1103 <li>update of the trio portability layer (Bjorn Reese)</li>
1104</ul>
1105
Daniel Veillard42766c02002-08-22 20:52:17 +0000[diff] [blame]1106<p><strong>2.4.24: Aug 22 2002</strong></p>
1107<ul>
1108 <li>XPath fixes (William), xf:escape-uri() (Wesley Terpstra)</li>
1109 <li>Python binding fixes: makefiles (William), generator, rpm build, x86-64
1110 (fcrozat)</li>
1111 <li>HTML &lt;style&gt; and boolean attributes serializer fixes</li>
1112 <li>C14N improvements by Aleksey</li>
Daniel Veillarde1662542002-08-28 11:50:59 +0000[diff] [blame]1113 <li>doc cleanups: Rick Jones</li>
Daniel Veillard42766c02002-08-22 20:52:17 +0000[diff] [blame]1114 <li>Windows compiler makefile updates: Igor and Elizabeth Barham</li>
1115 <li>XInclude: implementation of fallback and xml:base fixup added</li>
1116</ul>
1117
Daniel Veillard782afda2002-07-08 15:12:49 +0000[diff] [blame]1118<h3>2.4.23: July 6 2002</h3>
1119<ul>
1120 <li>performances patches: Peter Jacobi</li>
1121 <li>c14n fixes, testsuite and performances: Aleksey Sanin</li>
1122 <li>added xmlDocFormatDump: Chema Celorio</li>
1123 <li>new tutorial: John Fleck</li>
1124 <li>new hash functions and performances: Sander Vesik, portability fix from
1125 Peter Jacobi</li>
1126 <li>a number of bug fixes: XPath (William Brack, Richard Jinks), XML and
1127 HTML parsers, ID lookup function</li>
1128 <li>removal of all remaining sprintf: Aleksey Sanin</li>
1129</ul>
1130
Daniel Veillardc0801af2002-05-28 16:28:42 +0000[diff] [blame]1131<h3>2.4.22: May 27 2002</h3>
1132<ul>
1133 <li>a number of bug fixes: configure scripts, base handling, parser, memory
1134 usage, HTML parser, XPath, documentation (Christian Cornelssen),
Daniel Veillard21473672002-06-17 07:29:22 +0000[diff] [blame]1135 indentation, URI parsing</li>
Daniel Veillardc0801af2002-05-28 16:28:42 +0000[diff] [blame]1136 <li>Optimizations for XMLSec, fixing and making public some of the network
1137 protocol handlers (Aleksey)</li>
1138 <li>performance patch from Gary Pennington</li>
1139 <li>Charles Bozeman provided date and time support for XML Schemas
1140 datatypes</li>
1141</ul>
1142
Daniel Veillardcf27f7c2002-04-30 07:12:39 +0000[diff] [blame]1143<h3>2.4.21: Apr 29 2002</h3>
1144
1145<p>This release is both a bug fix release and also contains the early XML
1146Schemas <a href="http://www.w3.org/TR/xmlschema-1/">structures</a> and <a
1147href="http://www.w3.org/TR/xmlschema-2/">datatypes</a> code, beware, all
1148interfaces are likely to change, there is huge holes, it is clearly a work in
1149progress and don't even think of putting this code in a production system,
Daniel Veillarde6d8e202002-05-02 06:11:10 +0000[diff] [blame]1150it's actually not compiled in by default. The real fixes are:</p>
Daniel Veillardcf27f7c2002-04-30 07:12:39 +0000[diff] [blame]1151<ul>
1152 <li>a couple of bugs or limitations introduced in 2.4.20</li>
1153 <li>patches for Borland C++ and MSC by Igor</li>
1154 <li>some fixes on XPath strings and conformance patches by Richard
1155 Jinks</li>
1156 <li>patch from Aleksey for the ExcC14N specification</li>
1157 <li>OSF/1 bug fix by Bjorn</li>
Daniel Veillardaf43f632002-03-08 15:05:20 +0000[diff] [blame]1158</ul>
1159
Daniel Veillarda7084cd2002-04-15 17:12:47 +0000[diff] [blame]1160<h3>2.4.20: Apr 15 2002</h3>
1161<ul>
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]1162 <li>bug fixes: file descriptor leak, XPath, HTML output, DTD validation</li>
Daniel Veillarda7084cd2002-04-15 17:12:47 +0000[diff] [blame]1163 <li>XPath conformance testing by Richard Jinks</li>
1164 <li>Portability fixes: Solaris, MPE/iX, Windows, OSF/1, python bindings,
1165 libxml.m4</li>
1166</ul>
1167
Daniel Veillard19274092002-03-25 16:48:03 +0000[diff] [blame]1168<h3>2.4.19: Mar 25 2002</h3>
1169<ul>
1170 <li>bug fixes: half a dozen XPath bugs, Validation, ISO-Latin to UTF8
1171 encoder</li>
1172 <li>portability fixes in the HTTP code</li>
Daniel Veillardb2fb8ed2002-04-01 09:33:12 +0000[diff] [blame]1173 <li>memory allocation checks using valgrind, and profiling tests</li>
Daniel Veillard19274092002-03-25 16:48:03 +0000[diff] [blame]1174 <li>revamp of the Windows build and Makefiles</li>
1175</ul>
1176
Daniel Veillard34ce8be2002-03-18 19:37:11 +0000[diff] [blame]1177<h3>2.4.18: Mar 18 2002</h3>
1178<ul>
1179 <li>bug fixes: tree, SAX, canonicalization, validation, portability,
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]1180 XPath</li>
Daniel Veillard34ce8be2002-03-18 19:37:11 +0000[diff] [blame]1181 <li>removed the --with-buffer option it was becoming unmaintainable</li>
1182 <li>serious cleanup of the Python makefiles</li>
1183 <li>speedup patch to XPath very effective for DocBook stylesheets</li>
1184 <li>Fixes for Windows build, cleanup of the documentation</li>
1185</ul>
1186
Daniel Veillardaf43f632002-03-08 15:05:20 +0000[diff] [blame]1187<h3>2.4.17: Mar 8 2002</h3>
1188<ul>
1189 <li>a lot of bug fixes, including "namespace nodes have no parents in
1190 XPath"</li>
1191 <li>fixed/improved the Python wrappers, added more examples and more
1192 regression tests, XPath extension functions can now return node-sets</li>
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]1193 <li>added the XML Canonicalization support from Aleksey Sanin</li>
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]1194</ul>
1195
Daniel Veillard5f4b5992002-02-20 10:22:49 +0000[diff] [blame]1196<h3>2.4.16: Feb 20 2002</h3>
1197<ul>
1198 <li>a lot of bug fixes, most of them were triggered by the XML Testsuite
1199 from OASIS and W3C. Compliance has been significantly improved.</li>
1200 <li>a couple of portability fixes too.</li>
1201</ul>
1202
Daniel Veillard397ff112002-02-11 18:27:20 +0000[diff] [blame]1203<h3>2.4.15: Feb 11 2002</h3>
1204<ul>
1205 <li>Fixed the Makefiles, especially the python module ones</li>
1206 <li>A few bug fixes and cleanup</li>
1207 <li>Includes cleanup</li>
1208</ul>
1209
Daniel Veillardb6c1e2f2002-02-08 14:52:52 +0000[diff] [blame]1210<h3>2.4.14: Feb 8 2002</h3>
1211<ul>
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]1212 <li>Change of License to the <a
Daniel Veillardb6c1e2f2002-02-08 14:52:52 +0000[diff] [blame]1213 href="http://www.opensource.org/licenses/mit-license.html">MIT
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]1214 License</a> basically for integration in XFree86 codebase, and removing
1215 confusion around the previous dual-licensing</li>
Daniel Veillardb6c1e2f2002-02-08 14:52:52 +0000[diff] [blame]1216 <li>added Python bindings, beta software but should already be quite
1217 complete</li>
1218 <li>a large number of fixes and cleanups, especially for all tree
1219 manipulations</li>
1220 <li>cleanup of the headers, generation of a reference API definition in
1221 XML</li>
1222</ul>
1223
1224<h3>2.4.13: Jan 14 2002</h3>
Daniel Veillard744683d2002-01-14 17:30:20 +0000[diff] [blame]1225<ul>
1226 <li>update of the documentation: John Fleck and Charlie Bozeman</li>
1227 <li>cleanup of timing code from Justin Fletcher</li>
1228 <li>fixes for Windows and initial thread support on Win32: Igor and Serguei
1229 Narojnyi</li>
1230 <li>Cygwin patch from Robert Collins</li>
1231 <li>added xmlSetEntityReferenceFunc() for Keith Isdale work on xsldbg</li>
1232</ul>
1233
Daniel Veillardef90ba72001-12-07 14:24:22 +0000[diff] [blame]1234<h3>2.4.12: Dec 7 2001</h3>
1235<ul>
1236 <li>a few bug fixes: thread (Gary Pennington), xmllint (Geert Kloosterman),
1237 XML parser (Robin Berjon), XPointer (Danny Jamshy), I/O cleanups
1238 (robert)</li>
1239 <li>Eric Lavigne contributed project files for MacOS</li>
1240 <li>some makefiles cleanups</li>
1241</ul>
1242
Daniel Veillarda4871052001-11-26 13:19:48 +0000[diff] [blame]1243<h3>2.4.11: Nov 26 2001</h3>
1244<ul>
1245 <li>fixed a couple of errors in the includes, fixed a few bugs, some code
1246 cleanups</li>
1247 <li>xmllint man pages improvement by Heiko Rupp</li>
1248 <li>updated VMS build instructions from John A Fotheringham</li>
1249 <li>Windows Makefiles updates from Igor</li>
1250</ul>
1251
Daniel Veillard43d3f612001-11-10 11:57:23 +0000[diff] [blame]1252<h3>2.4.10: Nov 10 2001</h3>
1253<ul>
1254 <li>URI escaping fix (Joel Young)</li>
1255 <li>added xmlGetNodePath() (for paths or XPointers generation)</li>
1256 <li>Fixes namespace handling problems when using DTD and validation</li>
1257 <li>improvements on xmllint: Morus Walter patches for --format and
1258 --encode, Stefan Kost and Heiko Rupp improvements on the --shell</li>
1259 <li>fixes for xmlcatalog linking pointed by Weiqi Gao</li>
1260 <li>fixes to the HTML parser</li>
1261</ul>
1262
1263<h3>2.4.9: Nov 6 2001</h3>
1264<ul>
1265 <li>fixes more catalog bugs</li>
1266 <li>avoid a compilation problem, improve xmlGetLineNo()</li>
1267</ul>
1268
Daniel Veillarded421aa2001-11-04 21:22:45 +0000[diff] [blame]1269<h3>2.4.8: Nov 4 2001</h3>
1270<ul>
1271 <li>fixed SGML catalogs broken in previous release, updated xmlcatalog
1272 tool</li>
1273 <li>fixed a compile errors and some includes troubles.</li>
1274</ul>
1275
Daniel Veillard52dcab32001-10-30 12:51:17 +0000[diff] [blame]1276<h3>2.4.7: Oct 30 2001</h3>
1277<ul>
1278 <li>exported some debugging interfaces</li>
1279 <li>serious rewrite of the catalog code</li>
1280 <li>integrated Gary Pennington thread safety patch, added configure option
1281 and regression tests</li>
1282 <li>removed an HTML parser bug</li>
1283 <li>fixed a couple of potentially serious validation bugs</li>
1284 <li>integrated the SGML DocBook support in xmllint</li>
1285 <li>changed the nanoftp anonymous login passwd</li>
1286 <li>some I/O cleanup and a couple of interfaces for Perl wrapper</li>
1287 <li>general bug fixes</li>
1288 <li>updated xmllint man page by John Fleck</li>
1289 <li>some VMS and Windows updates</li>
1290</ul>
1291
Daniel Veillard60087f32001-10-10 09:45:09 +0000[diff] [blame]1292<h3>2.4.6: Oct 10 2001</h3>
1293<ul>
Daniel Veillard52dcab32001-10-30 12:51:17 +0000[diff] [blame]1294 <li>added an updated man pages by John Fleck</li>
Daniel Veillard60087f32001-10-10 09:45:09 +0000[diff] [blame]1295 <li>portability and configure fixes</li>
1296 <li>an infinite loop on the HTML parser was removed (William)</li>
1297 <li>Windows makefile patches from Igor</li>
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]1298 <li>fixed half a dozen bugs reported for libxml or libxslt</li>
Daniel Veillard60087f32001-10-10 09:45:09 +0000[diff] [blame]1299 <li>updated xmlcatalog to be able to modify SGML super catalogs</li>
1300</ul>
1301
Daniel Veillarddadd0872001-09-15 09:21:44 +0000[diff] [blame]1302<h3>2.4.5: Sep 14 2001</h3>
1303<ul>
1304 <li>Remove a few annoying bugs in 2.4.4</li>
1305 <li>forces the HTML serializer to output decimal charrefs since some
1306 version of Netscape can't handle hexadecimal ones</li>
1307</ul>
1308
1309<h3>1.8.16: Sep 14 2001</h3>
1310<ul>
1311 <li>maintenance release of the old libxml1 branch, couple of bug and
1312 portability fixes</li>
1313</ul>
1314
Daniel Veillard04382ae2001-09-12 18:51:30 +0000[diff] [blame]1315<h3>2.4.4: Sep 12 2001</h3>
1316<ul>
1317 <li>added --convert to xmlcatalog, bug fixes and cleanups of XML
1318 Catalog</li>
1319 <li>a few bug fixes and some portability changes</li>
1320 <li>some documentation cleanups</li>
1321</ul>
1322
Daniel Veillard39936902001-08-24 00:49:01 +0000[diff] [blame]1323<h3>2.4.3: Aug 23 2001</h3>
1324<ul>
1325 <li>XML Catalog support see the doc</li>
1326 <li>New NaN/Infinity floating point code</li>
1327 <li>A few bug fixes</li>
1328</ul>
1329
1330<h3>2.4.2: Aug 15 2001</h3>
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]1331<ul>
1332 <li>adds xmlLineNumbersDefault() to control line number generation</li>
1333 <li>lot of bug fixes</li>
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]1334 <li>the Microsoft MSC projects files should now be up to date</li>
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]1335 <li>inheritance of namespaces from DTD defaulted attributes</li>
1336 <li>fixes a serious potential security bug</li>
1337 <li>added a --format option to xmllint</li>
1338</ul>
1339
1340<h3>2.4.1: July 24 2001</h3>
1341<ul>
1342 <li>possibility to keep line numbers in the tree</li>
1343 <li>some computation NaN fixes</li>
1344 <li>extension of the XPath API</li>
1345 <li>cleanup for alpha and ia64 targets</li>
1346 <li>patch to allow saving through HTTP PUT or POST</li>
Daniel Veillard09ab7e12001-07-10 15:49:44 +0000[diff] [blame]1347</ul>
1348
1349<h3>2.4.0: July 10 2001</h3>
1350<ul>
1351 <li>Fixed a few bugs in XPath, validation, and tree handling.</li>
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]1352 <li>Fixed XML Base implementation, added a couple of examples to the
Daniel Veillard09ab7e12001-07-10 15:49:44 +0000[diff] [blame]1353 regression tests</li>
1354 <li>A bit of cleanup</li>
Daniel Veillardab8500d2000-10-15 21:06:19 +0000[diff] [blame]1355</ul>
1356
Daniel Veillard5b43fde2001-07-05 23:31:40 +0000[diff] [blame]1357<h3>2.3.14: July 5 2001</h3>
1358<ul>
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]1359 <li>fixed some entities problems and reduce memory requirement when
1360 substituting them</li>
Daniel Veillard5b43fde2001-07-05 23:31:40 +0000[diff] [blame]1361 <li>lots of improvements in the XPath queries interpreter can be
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]1362 substantially faster</li>
Daniel Veillard5b43fde2001-07-05 23:31:40 +0000[diff] [blame]1363 <li>Makefiles and configure cleanups</li>
1364 <li>Fixes to XPath variable eval, and compare on empty node set</li>
1365 <li>HTML tag closing bug fixed</li>
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]1366 <li>Fixed an URI reference computation problem when validating</li>
Daniel Veillard5b43fde2001-07-05 23:31:40 +0000[diff] [blame]1367</ul>
1368
Daniel Veillard2adbb512001-06-28 16:20:36 +0000[diff] [blame]1369<h3>2.3.13: June 28 2001</h3>
1370<ul>
1371 <li>2.3.12 configure.in was broken as well as the push mode XML parser</li>
1372 <li>a few more fixes for compilation on Windows MSC by Yon Derek</li>
1373</ul>
1374
1375<h3>1.8.14: June 28 2001</h3>
1376<ul>
1377 <li>Zbigniew Chyla gave a patch to use the old XML parser in push mode</li>
1378 <li>Small Makefile fix</li>
1379</ul>
1380
Daniel Veillard11648102001-06-26 16:08:24 +0000[diff] [blame]1381<h3>2.3.12: June 26 2001</h3>
1382<ul>
1383 <li>lots of cleanup</li>
1384 <li>a couple of validation fix</li>
1385 <li>fixed line number counting</li>
1386 <li>fixed serious problems in the XInclude processing</li>
1387 <li>added support for UTF8 BOM at beginning of entities</li>
1388 <li>fixed a strange gcc optimizer bugs in xpath handling of float, gcc-3.0
1389 miscompile uri.c (William), Thomas Leitner provided a fix for the
1390 optimizer on Tru64</li>
1391 <li>incorporated Yon Derek and Igor Zlatkovic fixes and improvements for
1392 compilation on Windows MSC</li>
1393 <li>update of libxml-doc.el (Felix Natter)</li>
1394 <li>fixed 2 bugs in URI normalization code</li>
1395</ul>
1396
Daniel Veillarde3c81b52001-06-17 14:50:34 +0000[diff] [blame]1397<h3>2.3.11: June 17 2001</h3>
1398<ul>
1399 <li>updates to trio, Makefiles and configure should fix some portability
1400 problems (alpha)</li>
1401 <li>fixed some HTML serialization problems (pre, script, and block/inline
1402 handling), added encoding aware APIs, cleanup of this code</li>
1403 <li>added xmlHasNsProp()</li>
1404 <li>implemented a specific PI for encoding support in the DocBook SGML
1405 parser</li>
1406 <li>some XPath fixes (-Infinity, / as a function parameter and namespaces
1407 node selection)</li>
1408 <li>fixed a performance problem and an error in the validation code</li>
1409 <li>fixed XInclude routine to implement the recursive behaviour</li>
1410 <li>fixed xmlFreeNode problem when libxml is included statically twice</li>
1411 <li>added --version to xmllint for bug reports</li>
1412</ul>
1413
Daniel Veillard2e4f1882001-06-01 10:11:57 +0000[diff] [blame]1414<h3>2.3.10: June 1 2001</h3>
1415<ul>
1416 <li>fixed the SGML catalog support</li>
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]1417 <li>a number of reported bugs got fixed, in XPath, iconv detection,
1418 XInclude processing</li>
Daniel Veillard2e4f1882001-06-01 10:11:57 +0000[diff] [blame]1419 <li>XPath string function should now handle unicode correctly</li>
1420</ul>
1421
Daniel Veillard4623acd2001-05-19 15:13:15 +0000[diff] [blame]1422<h3>2.3.9: May 19 2001</h3>
1423
1424<p>Lots of bugfixes, and added a basic SGML catalog support:</p>
1425<ul>
1426 <li>HTML push bugfix #54891 and another patch from Jonas Borgström</li>
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]1427 <li>some serious speed optimization again</li>
Daniel Veillard4623acd2001-05-19 15:13:15 +0000[diff] [blame]1428 <li>some documentation cleanups</li>
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]1429 <li>trying to get better linking on Solaris (-R)</li>
Daniel Veillard4623acd2001-05-19 15:13:15 +0000[diff] [blame]1430 <li>XPath API cleanup from Thomas Broyer</li>
1431 <li>Validation bug fixed #54631, added a patch from Gary Pennington, fixed
1432 xmlValidGetValidElements()</li>
1433 <li>Added an INSTALL file</li>
1434 <li>Attribute removal added to API: #54433</li>
1435 <li>added a basic support for SGML catalogs</li>
1436 <li>fixed xmlKeepBlanksDefault(0) API</li>
1437 <li>bugfix in xmlNodeGetLang()</li>
1438 <li>fixed a small configure portability problem</li>
1439 <li>fixed an inversion of SYSTEM and PUBLIC identifier in HTML document</li>
1440</ul>
1441
Daniel Veillarda265af72001-05-14 11:13:58 +0000[diff] [blame]1442<h3>1.8.13: May 14 2001</h3>
1443<ul>
1444 <li>bugfixes release of the old libxml1 branch used by Gnome</li>
1445</ul>
1446
Daniel Veillard3bbbe6f2001-05-03 11:15:37 +0000[diff] [blame]1447<h3>2.3.8: May 3 2001</h3>
1448<ul>
1449 <li>Integrated an SGML DocBook parser for the Gnome project</li>
1450 <li>Fixed a few things in the HTML parser</li>
1451 <li>Fixed some XPath bugs raised by XSLT use, tried to fix the floating
1452 point portability issue</li>
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]1453 <li>Speed improvement (8M/s for SAX, 3M/s for DOM, 1.5M/s for
1454 DOM+validation using the XML REC as input and a 700MHz celeron).</li>
Daniel Veillard3bbbe6f2001-05-03 11:15:37 +0000[diff] [blame]1455 <li>incorporated more Windows cleanup</li>
1456 <li>added xmlSaveFormatFile()</li>
1457 <li>fixed problems in copying nodes with entities references (gdome)</li>
1458 <li>removed some troubles surrounding the new validation module</li>
1459</ul>
1460
Daniel Veillarda41123c2001-04-22 19:31:20 +0000[diff] [blame]1461<h3>2.3.7: April 22 2001</h3>
1462<ul>
1463 <li>lots of small bug fixes, corrected XPointer</li>
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]1464 <li>Non deterministic content model validation support</li>
Daniel Veillarda41123c2001-04-22 19:31:20 +0000[diff] [blame]1465 <li>added xmlDocCopyNode for gdome2</li>
1466 <li>revamped the way the HTML parser handles end of tags</li>
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]1467 <li>XPath: corrections of namespaces support and number formatting</li>
Daniel Veillarda41123c2001-04-22 19:31:20 +0000[diff] [blame]1468 <li>Windows: Igor Zlatkovic patches for MSC compilation</li>
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]1469 <li>HTML output fixes from P C Chow and William M. Brack</li>
Daniel Veillarda41123c2001-04-22 19:31:20 +0000[diff] [blame]1470 <li>Improved validation speed sensible for DocBook</li>
1471 <li>fixed a big bug with ID declared in external parsed entities</li>
1472 <li>portability fixes, update of Trio from Bjorn Reese</li>
1473</ul>
1474
Daniel Veillardafc73112001-04-11 11:51:41 +0000[diff] [blame]1475<h3>2.3.6: April 8 2001</h3>
1476<ul>
1477 <li>Code cleanup using extreme gcc compiler warning options, found and
1478 cleared half a dozen potential problem</li>
1479 <li>the Eazel team found an XML parser bug</li>
1480 <li>cleaned up the user of some of the string formatting function. used the
1481 trio library code to provide the one needed when the platform is missing
1482 them</li>
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]1483 <li>xpath: removed a memory leak and fixed the predicate evaluation
1484 problem, extended the testsuite and cleaned up the result. XPointer seems
1485 broken ...</li>
Daniel Veillardafc73112001-04-11 11:51:41 +0000[diff] [blame]1486</ul>
1487
Daniel Veillard56a4cb82001-03-24 17:00:36 +0000[diff] [blame]1488<h3>2.3.5: Mar 23 2001</h3>
1489<ul>
1490 <li>Biggest change is separate parsing and evaluation of XPath expressions,
1491 there is some new APIs for this too</li>
1492 <li>included a number of bug fixes(XML push parser, 51876, notations,
1493 52299)</li>
1494 <li>Fixed some portability issues</li>
1495</ul>
1496
Daniel Veillarde356c282001-03-10 12:32:04 +0000[diff] [blame]1497<h3>2.3.4: Mar 10 2001</h3>
1498<ul>
1499 <li>Fixed bugs #51860 and #51861</li>
1500 <li>Added a global variable xmlDefaultBufferSize to allow default buffer
1501 size to be application tunable.</li>
1502 <li>Some cleanup in the validation code, still a bug left and this part
1503 should probably be rewritten to support ambiguous content model :-\</li>
1504 <li>Fix a couple of serious bugs introduced or raised by changes in 2.3.3
1505 parser</li>
1506 <li>Fixed another bug in xmlNodeGetContent()</li>
1507 <li>Bjorn fixed XPath node collection and Number formatting</li>
1508 <li>Fixed a loop reported in the HTML parsing</li>
1509 <li>blank space are reported even if the Dtd content model proves that they
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]1510 are formatting spaces, this is for XML conformance</li>
Daniel Veillarde356c282001-03-10 12:32:04 +0000[diff] [blame]1511</ul>
1512
Daniel Veillardb402c072001-03-01 17:28:58 +0000[diff] [blame]1513<h3>2.3.3: Mar 1 2001</h3>
1514<ul>
1515 <li>small change in XPath for XSLT</li>
1516 <li>documentation cleanups</li>
1517 <li>fix in validation by Gary Pennington</li>
1518 <li>serious parsing performances improvements</li>
1519</ul>
1520
Daniel Veillardec70e912001-02-26 20:10:45 +0000[diff] [blame]1521<h3>2.3.2: Feb 24 2001</h3>
Daniel Veillard71681102001-02-24 17:48:53 +0000[diff] [blame]1522<ul>
1523 <li>chasing XPath bugs, found a bunch, completed some TODO</li>
1524 <li>fixed a Dtd parsing bug</li>
1525 <li>fixed a bug in xmlNodeGetContent</li>
1526 <li>ID/IDREF support partly rewritten by Gary Pennington</li>
1527</ul>
1528
Daniel Veillardec70e912001-02-26 20:10:45 +0000[diff] [blame]1529<h3>2.3.1: Feb 15 2001</h3>
Daniel Veillard6e6a6cc2001-02-15 15:55:44 +0000[diff] [blame]1530<ul>
1531 <li>some XPath and HTML bug fixes for XSLT</li>
1532 <li>small extension of the hash table interfaces for DOM gdome2
1533 implementation</li>
1534 <li>A few bug fixes</li>
1535</ul>
1536
Daniel Veillardec70e912001-02-26 20:10:45 +0000[diff] [blame]1537<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 +0000[diff] [blame]1538<ul>
1539 <li>Lots of XPath bug fixes</li>
1540 <li>Add a mode with Dtd lookup but without validation error reporting for
1541 XSLT</li>
1542 <li>Add support for text node without escaping (XSLT)</li>
1543 <li>bug fixes for xmlCheckFilename</li>
1544 <li>validation code bug fixes from Gary Pennington</li>
1545 <li>Patch from Paul D. Smith correcting URI path normalization</li>
1546 <li>Patch to allow simultaneous install of libxml-devel and
1547 libxml2-devel</li>
1548 <li>the example Makefile is now fixed</li>
1549 <li>added HTML to the RPM packages</li>
1550 <li>tree copying bugfixes</li>
1551 <li>updates to Windows makefiles</li>
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]1552 <li>optimization patch from Bjorn Reese</li>
Daniel Veillard6e6a6cc2001-02-15 15:55:44 +0000[diff] [blame]1553</ul>
1554
Daniel Veillardec70e912001-02-26 20:10:45 +0000[diff] [blame]1555<h3>2.2.11: Jan 4 2001</h3>
Daniel Veillard503b8932001-01-05 06:36:31 +0000[diff] [blame]1556<ul>
1557 <li>bunch of bug fixes (memory I/O, xpath, ftp/http, ...)</li>
1558 <li>added htmlHandleOmittedElem()</li>
1559 <li>Applied Bjorn Reese's IPV6 first patch</li>
1560 <li>Applied Paul D. Smith patches for validation of XInclude results</li>
Daniel Veillard82687162001-01-22 15:32:01 +0000[diff] [blame]1561 <li>added XPointer xmlns() new scheme support</li>
Daniel Veillard503b8932001-01-05 06:36:31 +0000[diff] [blame]1562</ul>
1563
Daniel Veillard2ddd23d2000-11-25 10:42:19 +0000[diff] [blame]1564<h3>2.2.10: Nov 25 2000</h3>
Daniel Veillard9d343c42000-11-25 10:12:43 +0000[diff] [blame]1565<ul>
1566 <li>Fix the Windows problems of 2.2.8</li>
1567 <li>integrate OpenVMS patches</li>
1568 <li>better handling of some nasty HTML input</li>
1569 <li>Improved the XPointer implementation</li>
1570 <li>integrate a number of provided patches</li>
1571</ul>
1572
Daniel Veillard2ddd23d2000-11-25 10:42:19 +0000[diff] [blame]1573<h3>2.2.9: Nov 25 2000</h3>
1574<ul>
1575 <li>erroneous release :-(</li>
1576</ul>
1577
Daniel Veillard28929b22000-11-13 18:22:49 +0000[diff] [blame]1578<h3>2.2.8: Nov 13 2000</h3>
1579<ul>
1580 <li>First version of <a href="http://www.w3.org/TR/xinclude">XInclude</a>
1581 support</li>
1582 <li>Patch in conditional section handling</li>
1583 <li>updated MS compiler project</li>
1584 <li>fixed some XPath problems</li>
1585 <li>added an URI escaping function</li>
1586 <li>some other bug fixes</li>
1587</ul>
1588
1589<h3>2.2.7: Oct 31 2000</h3>
1590<ul>
1591 <li>added message redirection</li>
1592 <li>XPath improvements (thanks TOM !)</li>
1593 <li>xmlIOParseDTD() added</li>
1594 <li>various small fixes in the HTML, URI, HTTP and XPointer support</li>
1595 <li>some cleanup of the Makefile, autoconf and the distribution content</li>
1596</ul>
1597
Daniel Veillard29a11cc2000-10-25 13:32:39 +0000[diff] [blame]1598<h3>2.2.6: Oct 25 2000:</h3>
1599<ul>
1600 <li>Added an hash table module, migrated a number of internal structure to
1601 those</li>
1602 <li>Fixed a posteriori validation problems</li>
1603 <li>HTTP module cleanups</li>
1604 <li>HTML parser improvements (tag errors, script/style handling, attribute
1605 normalization)</li>
1606 <li>coalescing of adjacent text nodes</li>
1607 <li>couple of XPath bug fixes, exported the internal API</li>
1608</ul>
1609
Daniel Veillardab8500d2000-10-15 21:06:19 +0000[diff] [blame]1610<h3>2.2.5: Oct 15 2000:</h3>
Daniel Veillard4c3a2031999-11-19 17:46:26 +0000[diff] [blame]1611<ul>
Daniel Veillard189446d2000-10-13 10:23:06 +0000[diff] [blame]1612 <li>XPointer implementation and testsuite</li>
1613 <li>Lot of XPath fixes, added variable and functions registration, more
1614 tests</li>
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]1615 <li>Portability fixes, lots of enhancements toward an easy Windows build
1616 and release</li>
Daniel Veillard189446d2000-10-13 10:23:06 +0000[diff] [blame]1617 <li>Late validation fixes</li>
1618 <li>Integrated a lot of contributed patches</li>
1619 <li>added memory management docs</li>
Daniel Veillardab8500d2000-10-15 21:06:19 +0000[diff] [blame]1620 <li>a performance problem when using large buffer seems fixed</li>
Daniel Veillard189446d2000-10-13 10:23:06 +0000[diff] [blame]1621</ul>
1622
1623<h3>2.2.4: Oct 1 2000:</h3>
1624<ul>
1625 <li>main XPath problem fixed</li>
1626 <li>Integrated portability patches for Windows</li>
1627 <li>Serious bug fixes on the URI and HTML code</li>
Daniel Veillard361d8452000-04-03 19:48:13 +0000[diff] [blame]1628</ul>
1629
Daniel Veillardd5f97f82000-09-17 16:38:14 +0000[diff] [blame]1630<h3>2.2.3: Sep 17 2000</h3>
1631<ul>
1632 <li>bug fixes</li>
1633 <li>cleanup of entity handling code</li>
1634 <li>overall review of all loops in the parsers, all sprintf usage has been
1635 checked too</li>
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]1636 <li>Far better handling of larges Dtd. Validating against DocBook XML Dtd
Daniel Veillardd5f97f82000-09-17 16:38:14 +0000[diff] [blame]1637 works smoothly now.</li>
1638</ul>
1639
1640<h3>1.8.10: Sep 6 2000</h3>
1641<ul>
1642 <li>bug fix release for some Gnome projects</li>
1643</ul>
1644
1645<h3>2.2.2: August 12 2000</h3>
Daniel Veillard786d7c82000-08-12 23:38:57 +0000[diff] [blame]1646<ul>
1647 <li>mostly bug fixes</li>
Daniel Veillardec78c0f2000-08-25 10:25:23 +0000[diff] [blame]1648 <li>started adding routines to access xml parser context options</li>
Daniel Veillard786d7c82000-08-12 23:38:57 +0000[diff] [blame]1649</ul>
1650
Daniel Veillardd5f97f82000-09-17 16:38:14 +0000[diff] [blame]1651<h3>2.2.1: July 21 2000</h3>
Daniel Veillarda2679fa2000-07-22 02:38:15 +0000[diff] [blame]1652<ul>
1653 <li>a purely bug fixes release</li>
1654 <li>fixed an encoding support problem when parsing from a memory block</li>
1655 <li>fixed a DOCTYPE parsing problem</li>
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]1656 <li>removed a bug in the function allowing to override the memory
1657 allocation routines</li>
Daniel Veillarda2679fa2000-07-22 02:38:15 +0000[diff] [blame]1658</ul>
1659
Daniel Veillardd5f97f82000-09-17 16:38:14 +0000[diff] [blame]1660<h3>2.2.0: July 14 2000</h3>
Daniel Veillard94e90602000-07-17 14:38:19 +0000[diff] [blame]1661<ul>
1662 <li>applied a lot of portability fixes</li>
1663 <li>better encoding support/cleanup and saving (content is now always
1664 encoded in UTF-8)</li>
1665 <li>the HTML parser now correctly handles encodings</li>
1666 <li>added xmlHasProp()</li>
1667 <li>fixed a serious problem with &amp;#38;</li>
1668 <li>propagated the fix to FTP client</li>
1669 <li>cleanup, bugfixes, etc ...</li>
1670 <li>Added a page about <a href="encoding.html">libxml Internationalization
1671 support</a></li>
1672</ul>
1673
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]1674<h3>1.8.9: July 9 2000</h3>
1675<ul>
1676 <li>fixed the spec the RPMs should be better</li>
1677 <li>fixed a serious bug in the FTP implementation, released 1.8.9 to solve
1678 rpmfind users problem</li>
1679</ul>
1680
Daniel Veillard6388e172000-07-03 16:07:19 +0000[diff] [blame]1681<h3>2.1.1: July 1 2000</h3>
1682<ul>
1683 <li>fixes a couple of bugs in the 2.1.0 packaging</li>
1684 <li>improvements on the HTML parser</li>
1685</ul>
1686
Daniel Veillard3f6f7f62000-06-30 17:58:25 +0000[diff] [blame]1687<h3>2.1.0 and 1.8.8: June 29 2000</h3>
1688<ul>
Daniel Veillardc0801af2002-05-28 16:28:42 +0000[diff] [blame]1689 <li>1.8.8 is mostly a commodity package for upgrading to libxml2 according
1690 to <a href="upgrade.html">new instructions</a>. It fixes a nasty problem
Daniel Veillard3f6f7f62000-06-30 17:58:25 +0000[diff] [blame]1691 about &amp;#38; charref parsing</li>
1692 <li>2.1.0 also ease the upgrade from libxml v1 to the recent version. it
1693 also contains numerous fixes and enhancements:
1694 <ul>
1695 <li>added xmlStopParser() to stop parsing</li>
1696 <li>improved a lot parsing speed when there is large CDATA blocs</li>
1697 <li>includes XPath patches provided by Picdar Technology</li>
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]1698 <li>tried to fix as much as possible DTD validation and namespace
Daniel Veillard3f6f7f62000-06-30 17:58:25 +0000[diff] [blame]1699 related problems</li>
1700 <li>output to a given encoding has been added/tested</li>
1701 <li>lot of various fixes</li>
1702 </ul>
1703 </li>
1704</ul>
1705
Daniel Veillarde0aed302000-04-16 08:52:20 +0000[diff] [blame]1706<h3>2.0.0: Apr 12 2000</h3>
Daniel Veillard361d8452000-04-03 19:48:13 +0000[diff] [blame]1707<ul>
1708 <li>First public release of libxml2. If you are using libxml, it's a good
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]1709 idea to check the 1.x to 2.x upgrade instructions. NOTE: while initially
1710 scheduled for Apr 3 the release occurred only on Apr 12 due to massive
Daniel Veillarde0aed302000-04-16 08:52:20 +0000[diff] [blame]1711 workload.</li>
Daniel Veillard361d8452000-04-03 19:48:13 +0000[diff] [blame]1712 <li>The include are now located under $prefix/include/libxml (instead of
Daniel Veillarde0aed302000-04-16 08:52:20 +0000[diff] [blame]1713 $prefix/include/gnome-xml), they also are referenced by
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]1714 <pre>#include &lt;libxml/xxx.h&gt;</pre>
Daniel Veillarde0aed302000-04-16 08:52:20 +0000[diff] [blame]1715 <p>instead of</p>
Daniel Veillard361d8452000-04-03 19:48:13 +0000[diff] [blame]1716 <pre>#include "xxx.h"</pre>
1717 </li>
Daniel Veillard8f621982000-03-20 13:07:15 +0000[diff] [blame]1718 <li>a new URI module for parsing URIs and following strictly RFC 2396</li>
1719 <li>the memory allocation routines used by libxml can now be overloaded
1720 dynamically by using xmlMemSetup()</li>
Daniel Veillard361d8452000-04-03 19:48:13 +0000[diff] [blame]1721 <li>The previously CVS only tool tester has been renamed
1722 <strong>xmllint</strong> and is now installed as part of the libxml2
1723 package</li>
Daniel Veillarde0aed302000-04-16 08:52:20 +0000[diff] [blame]1724 <li>The I/O interface has been revamped. There is now ways to plug in
1725 specific I/O modules, either at the URI scheme detection level using
1726 xmlRegisterInputCallbacks() or by passing I/O functions when creating a
1727 parser context using xmlCreateIOParserCtxt()</li>
1728 <li>there is a C preprocessor macro LIBXML_VERSION providing the version
1729 number of the libxml module in use</li>
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]1730 <li>a number of optional features of libxml can now be excluded at
1731 configure time (FTP/HTTP/HTML/XPath/Debug)</li>
Daniel Veillardedfb29b2000-03-14 19:59:05 +0000[diff] [blame]1732</ul>
1733
1734<h3>2.0.0beta: Mar 14 2000</h3>
1735<ul>
1736 <li>This is a first Beta release of libxml version 2</li>
Daniel Veillarde356c282001-03-10 12:32:04 +0000[diff] [blame]1737 <li>It's available only from<a href="ftp://xmlsoft.org/">xmlsoft.org
1738 FTP</a>, it's packaged as libxml2-2.0.0beta and available as tar and
1739 RPMs</li>
Daniel Veillardedfb29b2000-03-14 19:59:05 +0000[diff] [blame]1740 <li>This version is now the head in the Gnome CVS base, the old one is
1741 available under the tag LIB_XML_1_X</li>
Daniel Veillardc0801af2002-05-28 16:28:42 +0000[diff] [blame]1742 <li>This includes a very large set of changes. From a programmatic point
1743 of view applications should not have to be modified too much, check the
1744 <a href="upgrade.html">upgrade page</a></li>
Daniel Veillardedfb29b2000-03-14 19:59:05 +0000[diff] [blame]1745 <li>Some interfaces may changes (especially a bit about encoding).</li>
1746 <li>the updates includes:
Daniel Veillard6c8b1172000-03-01 00:40:41 +0000[diff] [blame]1747 <ul>
Daniel Veillardedfb29b2000-03-14 19:59:05 +0000[diff] [blame]1748 <li>fix I18N support. ISO-Latin-x/UTF-8/UTF-16 (nearly) seems correctly
1749 handled now</li>
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]1750 <li>Better handling of entities, especially well-formedness checking
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]1751 and proper PEref extensions in external subsets</li>
Daniel Veillard6c8b1172000-03-01 00:40:41 +0000[diff] [blame]1752 <li>DTD conditional sections</li>
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]1753 <li>Validation now correctly handle entities content</li>
Daniel Veillard6c8b1172000-03-01 00:40:41 +0000[diff] [blame]1754 <li><a href="http://rpmfind.net/tools/gdome/messages/0039.html">change
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]1755 structures to accommodate DOM</a></li>
Daniel Veillard6c8b1172000-03-01 00:40:41 +0000[diff] [blame]1756 </ul>
1757 </li>
Daniel Veillardedfb29b2000-03-14 19:59:05 +0000[diff] [blame]1758 <li>Serious progress were made toward compliance, <a
1759 href="conf/result.html">here are the result of the test</a> against the
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]1760 OASIS testsuite (except the Japanese tests since I don't support that
Daniel Veillardedfb29b2000-03-14 19:59:05 +0000[diff] [blame]1761 encoding yet). This URL is rebuilt every couple of hours using the CVS
1762 head version.</li>
Daniel Veillarde41f2b72000-01-30 20:00:07 +0000[diff] [blame]1763</ul>
1764
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]1765<h3>1.8.7: Mar 6 2000</h3>
1766<ul>
1767 <li>This is a bug fix release:</li>
1768 <li>It is possible to disable the ignorable blanks heuristic used by
1769 libxml-1.x, a new function xmlKeepBlanksDefault(0) will allow this. Note
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]1770 that for adherence to XML spec, this behaviour will be disabled by
1771 default in 2.x . The same function will allow to keep compatibility for
1772 old code.</li>
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]1773 <li>Blanks in &lt;a&gt; &lt;/a&gt; constructs are not ignored anymore,
1774 avoiding heuristic is really the Right Way :-\</li>
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]1775 <li>The unchecked use of snprintf which was breaking libxml-1.8.6
1776 compilation on some platforms has been fixed</li>
1777 <li>nanoftp.c nanohttp.c: Fixed '#' and '?' stripping when processing
1778 URIs</li>
1779</ul>
1780
Daniel Veillarde41f2b72000-01-30 20:00:07 +0000[diff] [blame]1781<h3>1.8.6: Jan 31 2000</h3>
1782<ul>
1783 <li>added a nanoFTP transport module, debugged until the new version of <a
1784 href="http://rpmfind.net/linux/rpm2html/rpmfind.html">rpmfind</a> can use
1785 it without troubles</li>
Daniel Veillardda07c342000-01-25 18:31:22 +0000[diff] [blame]1786</ul>
1787
1788<h3>1.8.5: Jan 21 2000</h3>
1789<ul>
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]1790 <li>adding APIs to parse a well balanced chunk of XML (production <a
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]1791 href="http://www.w3.org/TR/REC-xml#NT-content">[43] content</a> of the
1792 XML spec)</li>
Daniel Veillard461a66c2000-01-18 18:01:01 +0000[diff] [blame]1793 <li>fixed a hideous bug in xmlGetProp pointed by Rune.Djurhuus@fast.no</li>
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]1794 <li>Jody Goldberg &lt;jgoldberg@home.com&gt; provided another patch trying
1795 to solve the zlib checks problems</li>
Daniel Veillard461a66c2000-01-18 18:01:01 +0000[diff] [blame]1796 <li>The current state in gnome CVS base is expected to ship as 1.8.5 with
1797 gnumeric soon</li>
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]1798</ul>
1799
1800<h3>1.8.4: Jan 13 2000</h3>
1801<ul>
1802 <li>bug fixes, reintroduced xmlNewGlobalNs(), fixed xmlNewNs()</li>
1803 <li>all exit() call should have been removed from libxml</li>
1804 <li>fixed a problem with INCLUDE_WINSOCK on WIN32 platform</li>
1805 <li>added newDocFragment()</li>
Daniel Veillardf84f71f2000-01-05 19:54:23 +0000[diff] [blame]1806</ul>
1807
1808<h3>1.8.3: Jan 5 2000</h3>
1809<ul>
1810 <li>a Push interface for the XML and HTML parsers</li>
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]1811 <li>a shell-like interface to the document tree (try tester --shell :-)</li>
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]1812 <li>lots of bug fixes and improvement added over XMas holidays</li>
Daniel Veillard437b87b2000-01-03 17:30:46 +0000[diff] [blame]1813 <li>fixed the DTD parsing code to work with the xhtml DTD</li>
Daniel Veillardf84f71f2000-01-05 19:54:23 +0000[diff] [blame]1814 <li>added xmlRemoveProp(), xmlRemoveID() and xmlRemoveRef()</li>
1815 <li>Fixed bugs in xmlNewNs()</li>
Daniel Veillard437b87b2000-01-03 17:30:46 +0000[diff] [blame]1816 <li>External entity loading code has been revamped, now it uses
Daniel Veillardf84f71f2000-01-05 19:54:23 +0000[diff] [blame]1817 xmlLoadExternalEntity(), some fix on entities processing were added</li>
Daniel Veillard437b87b2000-01-03 17:30:46 +0000[diff] [blame]1818 <li>cleaned up WIN32 includes of socket stuff</li>
Daniel Veillard5cb5ab81999-12-21 15:35:29 +0000[diff] [blame]1819</ul>
1820
1821<h3>1.8.2: Dec 21 1999</h3>
1822<ul>
Daniel Veillardb24054a1999-12-18 15:32:46 +0000[diff] [blame]1823 <li>I got another problem with includes and C++, I hope this issue is fixed
1824 for good this time</li>
Daniel Veillard5cb5ab81999-12-21 15:35:29 +0000[diff] [blame]1825 <li>Added a few tree modification functions: xmlReplaceNode,
1826 xmlAddPrevSibling, xmlAddNextSibling, xmlNodeSetName and
1827 xmlDocSetRootElement</li>
1828 <li>Tried to improve the HTML output with help from <a
1829 href="mailto:clahey@umich.edu">Chris Lahey</a></li>
Daniel Veillarde4e51311999-12-18 15:32:46 +0000[diff] [blame]1830</ul>
Daniel Veillardb24054a1999-12-18 15:32:46 +0000[diff] [blame]1831
Daniel Veillarde4e51311999-12-18 15:32:46 +0000[diff] [blame]1832<h3>1.8.1: Dec 18 1999</h3>
1833<ul>
1834 <li>various patches to avoid troubles when using libxml with C++ compilers
1835 the "namespace" keyword and C escaping in include files</li>
1836 <li>a problem in one of the core macros IS_CHAR was corrected</li>
1837 <li>fixed a bug introduced in 1.8.0 breaking default namespace processing,
1838 and more specifically the Dia application</li>
Daniel Veillard944b5ff1999-12-15 19:08:24 +0000[diff] [blame]1839 <li>fixed a posteriori validation (validation after parsing, or by using a
1840 Dtd not specified in the original document)</li>
Daniel Veillardb24054a1999-12-18 15:32:46 +0000[diff] [blame]1841 <li>fixed a bug in</li>
Daniel Veillard10a2c651999-12-12 13:03:50 +0000[diff] [blame]1842</ul>
1843
1844<h3>1.8.0: Dec 12 1999</h3>
1845<ul>
1846 <li>cleanup, especially memory wise</li>
1847 <li>the parser should be more reliable, especially the HTML one, it should
1848 not crash, whatever the input !</li>
1849 <li>Integrated various patches, especially a speedup improvement for large
1850 dataset from <a href="mailto:cnygard@bellatlantic.net">Carl Nygard</a>,
1851 configure with --with-buffers to enable them.</li>
1852 <li>attribute normalization, oops should have been added long ago !</li>
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]1853 <li>attributes defaulted from DTDs should be available, xmlSetProp() now
1854 does entities escaping by default.</li>
Daniel Veillard4c3a2031999-11-19 17:46:26 +0000[diff] [blame]1855</ul>
Daniel Veillard35008381999-10-25 13:15:52 +0000[diff] [blame]1856
1857<h3>1.7.4: Oct 25 1999</h3>
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]1858<ul>
Daniel Veillard35008381999-10-25 13:15:52 +0000[diff] [blame]1859 <li>Lots of HTML improvement</li>
1860 <li>Fixed some errors when saving both XML and HTML</li>
1861 <li>More examples, the regression tests should now look clean</li>
1862 <li>Fixed a bug with contiguous charref</li>
1863</ul>
1864
1865<h3>1.7.3: Sep 29 1999</h3>
1866<ul>
1867 <li>portability problems fixed</li>
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]1868 <li>snprintf was used unconditionally, leading to link problems on system
Daniel Veillard35008381999-10-25 13:15:52 +0000[diff] [blame]1869 were it's not available, fixed</li>
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]1870</ul>
1871
1872<h3>1.7.1: Sep 24 1999</h3>
1873<ul>
1874 <li>The basic type for strings manipulated by libxml has been renamed in
1875 1.7.1 from <strong>CHAR</strong> to <strong>xmlChar</strong>. The reason
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]1876 is that CHAR was conflicting with a predefined type on Windows. However
1877 on non WIN32 environment, compatibility is provided by the way of a
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]1878 <strong>#define </strong>.</li>
1879 <li>Changed another error : the use of a structure field called errno, and
1880 leading to troubles on platforms where it's a macro</li>
1881</ul>
1882
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]1883<h3>1.7.0: Sep 23 1999</h3>
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]1884<ul>
1885 <li>Added the ability to fetch remote DTD or parsed entities, see the <a
Daniel Veillard9cb5ff42001-01-29 08:22:21 +0000[diff] [blame]1886 href="html/libxml-nanohttp.html">nanohttp</a> module.</li>
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]1887 <li>Added an errno to report errors by another mean than a simple printf
1888 like callback</li>
1889 <li>Finished ID/IDREF support and checking when validation</li>
1890 <li>Serious memory leaks fixed (there is now a <a
Daniel Veillard9cb5ff42001-01-29 08:22:21 +0000[diff] [blame]1891 href="html/libxml-xmlmemory.html">memory wrapper</a> module)</li>
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]1892 <li>Improvement of <a href="http://www.w3.org/TR/xpath">XPath</a>
1893 implementation</li>
1894 <li>Added an HTML parser front-end</li>
1895</ul>
1896
1897<h2><a name="XML">XML</a></h2>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]1898
Daniel Veillard402e8c82000-02-29 22:57:47 +0000[diff] [blame]1899<p><a href="http://www.w3.org/TR/REC-xml">XML is a standard</a> for
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]1900markup-based structured documents. Here is <a name="example">an example XML
1901document</a>:</p>
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]1902<pre>&lt;?xml version="1.0"?&gt;
1903&lt;EXAMPLE prop1="gnome is great" prop2="&amp;amp; linux too"&gt;
1904 &lt;head&gt;
1905 &lt;title&gt;Welcome to Gnome&lt;/title&gt;
1906 &lt;/head&gt;
1907 &lt;chapter&gt;
1908 &lt;title&gt;The Linux adventure&lt;/title&gt;
1909 &lt;p&gt;bla bla bla ...&lt;/p&gt;
1910 &lt;image href="linus.gif"/&gt;
1911 &lt;p&gt;...&lt;/p&gt;
1912 &lt;/chapter&gt;
1913&lt;/EXAMPLE&gt;</pre>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]1914
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]1915<p>The first line specifies that it is an XML document and gives useful
Daniel Veillard42766c02002-08-22 20:52:17 +0000[diff] [blame]1916information about its encoding. Then the rest of the document is a text
1917format whose structure is specified by tags between brackets. <strong>Each
1918tag opened has to be closed</strong>. XML is pedantic about this. However, if
1919a tag is empty (no content), a single tag can serve as both the opening and
1920closing tag if it ends with <code>/&gt;</code> rather than with
1921<code>&gt;</code>. Note that, for example, the image tag has no content (just
1922an attribute) and is closed by ending the tag with <code>/&gt;</code>.</p>
Daniel Veillardccb09631998-10-27 06:21:04 +0000[diff] [blame]1923
Daniel Veillard42766c02002-08-22 20:52:17 +0000[diff] [blame]1924<p>XML can be applied successfully to a wide range of tasks, ranging from
1925long term structured document maintenance (where it follows the steps of
1926SGML) to simple data encoding mechanisms like configuration file formatting
1927(glade), spreadsheets (gnumeric), or even shorter lived documents such as
1928WebDAV where it is used to encode remote calls between a client and a
1929server.</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]1930
Daniel Veillard82687162001-01-22 15:32:01 +0000[diff] [blame]1931<h2><a name="XSLT">XSLT</a></h2>
1932
Daniel Veillard6e6a6cc2001-02-15 15:55:44 +0000[diff] [blame]1933<p>Check <a href="http://xmlsoft.org/XSLT">the separate libxslt page</a></p>
1934
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]1935<p><a href="http://www.w3.org/TR/xslt">XSL Transformations</a>, is a
1936language for transforming XML documents into other XML documents (or
1937HTML/textual output).</p>
Daniel Veillard82687162001-01-22 15:32:01 +0000[diff] [blame]1938
Daniel Veillard560c2a42003-07-06 21:13:49 +0000[diff] [blame]1939<p>A separate library called libxslt is available implementing XSLT-1.0 for
1940libxml2. This module "libxslt" too can be found in the Gnome CVS base.</p>
Daniel Veillard82687162001-01-22 15:32:01 +0000[diff] [blame]1941
Daniel Veillard383b1472001-01-23 11:39:52 +0000[diff] [blame]1942<p>You can check the <a
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]1943href="http://cvs.gnome.org/lxr/source/libxslt/FEATURES">features</a>
1944supported and the progresses on the <a
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]1945href="http://cvs.gnome.org/lxr/source/libxslt/ChangeLog"
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]1946name="Changelog">Changelog</a>.</p>
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]1947
1948<h2><a name="Python">Python and bindings</a></h2>
1949
Daniel Veillard42766c02002-08-22 20:52:17 +0000[diff] [blame]1950<p>There are a number of language bindings and wrappers available for
1951libxml2, the list below is not exhaustive. Please contact the <a
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]1952href="http://mail.gnome.org/mailman/listinfo/xml-bindings">xml-bindings@gnome.org</a>
1953(<a href="http://mail.gnome.org/archives/xml-bindings/">archives</a>) in
1954order to get updates to this list or to discuss the specific topic of libxml2
1955or libxslt wrappers or bindings:</p>
1956<ul>
Daniel Veillardc14401e2002-11-20 14:28:17 +0000[diff] [blame]1957 <li><a href="http://libxmlplusplus.sourceforge.net/">Libxml++</a> seems the
1958 most up-to-date C++ bindings for libxml2, check the <a
1959 href="http://libxmlplusplus.sourceforge.net/reference/html/hierarchy.html">documentation</a>
1960 and the <a
1961 href="http://cvs.sourceforge.net/cgi-bin/viewcvs.cgi/libxmlplusplus/libxml%2b%2b/examples/">examples</a>.</li>
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]1962 <li>There is another <a href="http://libgdome-cpp.berlios.de/">C++ wrapper
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]1963 based on the gdome2 bindings</a> maintained by Tobias Peters.</li>
Daniel Veillard9b6fd302002-05-13 12:06:47 +0000[diff] [blame]1964 <li>and a third C++ wrapper by Peter Jones &lt;pjones@pmade.org&gt;
1965 <p>Website: <a
1966 href="http://pmade.org/pjones/software/xmlwrapp/">http://pmade.org/pjones/software/xmlwrapp/</a></p>
1967 </li>
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]1968 <li><a
1969 href="http://mail.gnome.org/archives/xml/2001-March/msg00014.html">Matt
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]1970 Sergeant</a> developed <a
1971 href="http://axkit.org/download/">XML::LibXSLT</a>, a Perl wrapper for
Daniel Veillardaf43f632002-03-08 15:05:20 +0000[diff] [blame]1972 libxml2/libxslt as part of the <a href="http://axkit.com/">AxKit XML
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]1973 application server</a>.</li>
Daniel Veillard4ac494b2003-09-18 15:08:00 +0000[diff] [blame]1974 <li>If you're interested into scripting XML processing, have a look at <a
1975 href="http://xsh.sourceforge.net/">XSH</a> an XML editing shell based on
1976 Libxml2 Perl bindings.</li>
Daniel Veillard21473672002-06-17 07:29:22 +0000[diff] [blame]1977 <li><a href="mailto:dkuhlman@cutter.rexx.com">Dave Kuhlman</a> provides an
Daniel Veillardaf43f632002-03-08 15:05:20 +0000[diff] [blame]1978 earlier version of the libxml/libxslt <a
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]1979 href="http://www.rexx.com/~dkuhlman">wrappers for Python</a>.</li>
Daniel Veillard21473672002-06-17 07:29:22 +0000[diff] [blame]1980 <li>Gopal.V and Peter Minten develop <a
1981 href="http://savannah.gnu.org/projects/libxmlsharp">libxml#</a>, a set of
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]1982 C# libxml2 bindings.</li>
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]1983 <li>Petr Kozelka provides <a
1984 href="http://sourceforge.net/projects/libxml2-pas">Pascal units to glue
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]1985 libxml2</a> with Kylix, Delphi and other Pascal compilers.</li>
Daniel Veillardb2fb8ed2002-04-01 09:33:12 +0000[diff] [blame]1986 <li>Uwe Fechner also provides <a
1987 href="http://sourceforge.net/projects/idom2-pas/">idom2</a>, a DOM2
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]1988 implementation for Kylix2/D5/D6 from Borland.</li>
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]1989 <li>Wai-Sun "Squidster" Chia provides <a
1990 href="http://www.rubycolor.org/arc/redist/">bindings for Ruby</a> and
1991 libxml2 bindings are also available in Ruby through the <a
1992 href="http://libgdome-ruby.berlios.de/">libgdome-ruby</a> module
1993 maintained by Tobias Peters.</li>
Daniel Veillardaf43f632002-03-08 15:05:20 +0000[diff] [blame]1994 <li>Steve Ball and contributors maintains <a
1995 href="http://tclxml.sourceforge.net/">libxml2 and libxslt bindings for
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]1996 Tcl</a>.</li>
Daniel Veillardaf43f632002-03-08 15:05:20 +0000[diff] [blame]1997 <li>There is support for libxml2 in the DOM module of PHP.</li>
Daniel Veillard41b01a82003-02-27 11:09:06 +0000[diff] [blame]1998 <li><a href="http://savannah.gnu.org/projects/classpathx/">LibxmlJ</a> is
Daniel Veillard806cada2003-03-19 21:58:59 +0000[diff] [blame]1999 an effort to create a 100% JAXP-compatible Java wrapper for libxml2 and
2000 libxslt as part of GNU ClasspathX project.</li>
Daniel Veillard6d373a22003-11-04 10:26:43 +0000[diff] [blame]2001 <li>Patrick McPhee provides Rexx bindings fof libxml2 and libxslt, look for
2002 <a href="http://www.interlog.com/~ptjm/software.html">RexxXML</a>.</li>
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]2003</ul>
2004
Daniel Veillardc0801af2002-05-28 16:28:42 +0000[diff] [blame]2005<p>The distribution includes a set of Python bindings, which are guaranteed
2006to be maintained as part of the library in the future, though the Python
Daniel Veillard41b01a82003-02-27 11:09:06 +0000[diff] [blame]2007interface have not yet reached the completeness of the C API.</p>
Daniel Veillard7b4b2f92003-01-06 13:11:20 +0000[diff] [blame]2008
Daniel Veillard27907c72002-12-16 16:05:58 +0000[diff] [blame]2009<p><a href="mailto:stephane.bidoul@softwareag.com">Stéphane Bidoul</a>
Daniel Veillard7b4b2f92003-01-06 13:11:20 +0000[diff] [blame]2010maintains <a href="http://users.skynet.be/sbi/libxml-python/">a Windows port
2011of the Python bindings</a>.</p>
Daniel Veillardaf43f632002-03-08 15:05:20 +0000[diff] [blame]2012
Daniel Veillard7ef0fcb2002-12-14 10:38:55 +0000[diff] [blame]2013<p>Note to people interested in building bindings, the API is formalized as
2014<a href="libxml2-api.xml">an XML API description file</a> which allows to
2015automate a large part of the Python bindings, this includes function
Daniel Veillard7b4b2f92003-01-06 13:11:20 +0000[diff] [blame]2016descriptions, enums, structures, typedefs, etc... The Python script used to
2017build the bindings is python/generator.py in the source distribution.</p>
Daniel Veillard7ef0fcb2002-12-14 10:38:55 +0000[diff] [blame]2018
Daniel Veillardaf43f632002-03-08 15:05:20 +0000[diff] [blame]2019<p>To install the Python bindings there are 2 options:</p>
Daniel Veillard0b79dfe2002-02-23 13:02:31 +0000[diff] [blame]2020<ul>
Daniel Veillardaf43f632002-03-08 15:05:20 +0000[diff] [blame]2021 <li>If you use an RPM based distribution, simply install the <a
2022 href="http://rpmfind.net/linux/rpm2html/search.php?query=libxml2-python">libxml2-python
2023 RPM</a> (and if needed the <a
2024 href="http://rpmfind.net/linux/rpm2html/search.php?query=libxslt-python">libxslt-python
2025 RPM</a>).</li>
2026 <li>Otherwise use the <a href="ftp://xmlsoft.org/python/">libxml2-python
2027 module distribution</a> corresponding to your installed version of
2028 libxml2 and libxslt. Note that to install it you will need both libxml2
2029 and libxslt installed and run "python setup.py build install" in the
2030 module tree.</li>
Daniel Veillard0b79dfe2002-02-23 13:02:31 +0000[diff] [blame]2031</ul>
Daniel Veillardaf43f632002-03-08 15:05:20 +0000[diff] [blame]2032
2033<p>The distribution includes a set of examples and regression tests for the
2034python bindings in the <code>python/tests</code> directory. Here are some
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]2035excerpts from those tests:</p>
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]2036
2037<h3>tst.py:</h3>
2038
2039<p>This is a basic test of the file interface and DOM navigation:</p>
MST 2003 John Fleck2dffb762003-11-29 04:41:24 +0000[diff] [blame]2040<pre>import libxml2, sys
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]2041
2042doc = libxml2.parseFile("tst.xml")
2043if doc.name != "tst.xml":
2044 print "doc.name failed"
2045 sys.exit(1)
2046root = doc.children
2047if root.name != "doc":
2048 print "root.name failed"
2049 sys.exit(1)
2050child = root.children
2051if child.name != "foo":
2052 print "child.name failed"
2053 sys.exit(1)
2054doc.freeDoc()</pre>
2055
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]2056<p>The Python module is called libxml2; parseFile is the equivalent of
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]2057xmlParseFile (most of the bindings are automatically generated, and the xml
2058prefix is removed and the casing convention are kept). All node seen at the
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]2059binding level share the same subset of accessors:</p>
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]2060<ul>
Daniel Veillardaf43f632002-03-08 15:05:20 +0000[diff] [blame]2061 <li><code>name</code> : returns the node name</li>
Daniel Veillardc0801af2002-05-28 16:28:42 +0000[diff] [blame]2062 <li><code>type</code> : returns a string indicating the node type</li>
Daniel Veillardaf43f632002-03-08 15:05:20 +0000[diff] [blame]2063 <li><code>content</code> : returns the content of the node, it is based on
2064 xmlNodeGetContent() and hence is recursive.</li>
2065 <li><code>parent</code> , <code>children</code>, <code>last</code>,
2066 <code>next</code>, <code>prev</code>, <code>doc</code>,
2067 <code>properties</code>: pointing to the associated element in the tree,
2068 those may return None in case no such link exists.</li>
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]2069</ul>
2070
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]2071<p>Also note the need to explicitly deallocate documents with freeDoc() .
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]2072Reference counting for libxml2 trees would need quite a lot of work to
2073function properly, and rather than risk memory leaks if not implemented
2074correctly it sounds safer to have an explicit function to free a tree. The
2075wrapper python objects like doc, root or child are them automatically garbage
2076collected.</p>
2077
2078<h3>validate.py:</h3>
2079
2080<p>This test check the validation interfaces and redirection of error
2081messages:</p>
2082<pre>import libxml2
2083
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]2084#deactivate error messages from the validation
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]2085def noerr(ctx, str):
2086 pass
2087
2088libxml2.registerErrorHandler(noerr, None)
2089
2090ctxt = libxml2.createFileParserCtxt("invalid.xml")
2091ctxt.validate(1)
2092ctxt.parseDocument()
2093doc = ctxt.doc()
2094valid = ctxt.isValid()
2095doc.freeDoc()
2096if valid != 0:
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]2097 print "validity check failed"</pre>
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]2098
2099<p>The first thing to notice is the call to registerErrorHandler(), it
2100defines a new error handler global to the library. It is used to avoid seeing
2101the error messages when trying to validate the invalid document.</p>
2102
2103<p>The main interest of that test is the creation of a parser context with
2104createFileParserCtxt() and how the behaviour can be changed before calling
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]2105parseDocument() . Similarly the informations resulting from the parsing phase
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]2106are also available using context methods.</p>
2107
2108<p>Contexts like nodes are defined as class and the libxml2 wrappers maps the
2109C function interfaces in terms of objects method as much as possible. The
2110best to get a complete view of what methods are supported is to look at the
2111libxml2.py module containing all the wrappers.</p>
2112
2113<h3>push.py:</h3>
2114
2115<p>This test show how to activate the push parser interface:</p>
2116<pre>import libxml2
2117
2118ctxt = libxml2.createPushParser(None, "&lt;foo", 4, "test.xml")
2119ctxt.parseChunk("/&gt;", 2, 1)
2120doc = ctxt.doc()
2121
2122doc.freeDoc()</pre>
2123
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]2124<p>The context is created with a special call based on the
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]2125xmlCreatePushParser() from the C library. The first argument is an optional
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]2126SAX callback object, then the initial set of data, the length and the name of
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]2127the resource in case URI-References need to be computed by the parser.</p>
2128
2129<p>Then the data are pushed using the parseChunk() method, the last call
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]2130setting the third argument terminate to 1.</p>
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]2131
2132<h3>pushSAX.py:</h3>
2133
2134<p>this test show the use of the event based parsing interfaces. In this case
2135the parser does not build a document, but provides callback information as
2136the parser makes progresses analyzing the data being provided:</p>
2137<pre>import libxml2
2138log = ""
2139
2140class callback:
2141 def startDocument(self):
2142 global log
2143 log = log + "startDocument:"
2144
2145 def endDocument(self):
2146 global log
2147 log = log + "endDocument:"
2148
2149 def startElement(self, tag, attrs):
2150 global log
2151 log = log + "startElement %s %s:" % (tag, attrs)
2152
2153 def endElement(self, tag):
2154 global log
2155 log = log + "endElement %s:" % (tag)
2156
2157 def characters(self, data):
2158 global log
2159 log = log + "characters: %s:" % (data)
2160
2161 def warning(self, msg):
2162 global log
2163 log = log + "warning: %s:" % (msg)
2164
2165 def error(self, msg):
2166 global log
2167 log = log + "error: %s:" % (msg)
2168
2169 def fatalError(self, msg):
2170 global log
2171 log = log + "fatalError: %s:" % (msg)
2172
2173handler = callback()
2174
2175ctxt = libxml2.createPushParser(handler, "&lt;foo", 4, "test.xml")
2176chunk = " url='tst'&gt;b"
2177ctxt.parseChunk(chunk, len(chunk), 0)
2178chunk = "ar&lt;/foo&gt;"
2179ctxt.parseChunk(chunk, len(chunk), 1)
2180
Daniel Veillardfcbfa2d2002-02-21 17:54:27 +0000[diff] [blame]2181reference = "startDocument:startElement foo {'url': 'tst'}:" + \
2182 "characters: bar:endElement foo:endDocument:"
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]2183if log != reference:
2184 print "Error got: %s" % log
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]2185 print "Expected: %s" % reference</pre>
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]2186
2187<p>The key object in that test is the handler, it provides a number of entry
2188points which can be called by the parser as it makes progresses to indicate
2189the information set obtained. The full set of callback is larger than what
2190the callback class in that specific example implements (see the SAX
2191definition for a complete list). The wrapper will only call those supplied by
2192the object when activated. The startElement receives the names of the element
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]2193and a dictionary containing the attributes carried by this element.</p>
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]2194
2195<p>Also note that the reference string generated from the callback shows a
2196single character call even though the string "bar" is passed to the parser
2197from 2 different call to parseChunk()</p>
2198
2199<h3>xpath.py:</h3>
2200
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]2201<p>This is a basic test of XPath wrappers support</p>
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]2202<pre>import libxml2
2203
2204doc = libxml2.parseFile("tst.xml")
2205ctxt = doc.xpathNewContext()
2206res = ctxt.xpathEval("//*")
2207if len(res) != 2:
2208 print "xpath query: wrong node set size"
2209 sys.exit(1)
2210if res[0].name != "doc" or res[1].name != "foo":
2211 print "xpath query: wrong node set value"
2212 sys.exit(1)
2213doc.freeDoc()
2214ctxt.xpathFreeContext()</pre>
2215
2216<p>This test parses a file, then create an XPath context to evaluate XPath
2217expression on it. The xpathEval() method execute an XPath query and returns
2218the result mapped in a Python way. String and numbers are natively converted,
2219and node sets are returned as a tuple of libxml2 Python nodes wrappers. Like
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]2220the document, the XPath context need to be freed explicitly, also not that
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]2221the result of the XPath query may point back to the document tree and hence
2222the document must be freed after the result of the query is used.</p>
2223
2224<h3>xpathext.py:</h3>
2225
2226<p>This test shows how to extend the XPath engine with functions written in
2227python:</p>
2228<pre>import libxml2
2229
2230def foo(ctx, x):
2231 return x + 1
2232
2233doc = libxml2.parseFile("tst.xml")
2234ctxt = doc.xpathNewContext()
2235libxml2.registerXPathFunction(ctxt._o, "foo", None, foo)
2236res = ctxt.xpathEval("foo(1)")
2237if res != 2:
2238 print "xpath extension failure"
2239doc.freeDoc()
2240ctxt.xpathFreeContext()</pre>
2241
2242<p>Note how the extension function is registered with the context (but that
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]2243part is not yet finalized, this may change slightly in the future).</p>
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]2244
2245<h3>tstxpath.py:</h3>
2246
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]2247<p>This test is similar to the previous one but shows how the extension
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]2248function can access the XPath evaluation context:</p>
2249<pre>def foo(ctx, x):
2250 global called
2251
2252 #
2253 # test that access to the XPath evaluation contexts
2254 #
2255 pctxt = libxml2.xpathParserContext(_obj=ctx)
2256 ctxt = pctxt.context()
2257 called = ctxt.function()
2258 return x + 1</pre>
2259
2260<p>All the interfaces around the XPath parser(or rather evaluation) context
2261are not finalized, but it should be sufficient to do contextual work at the
2262evaluation point.</p>
2263
2264<h3>Memory debugging:</h3>
2265
2266<p>last but not least, all tests starts with the following prologue:</p>
2267<pre>#memory debug specific
Daniel Veillardaf43f632002-03-08 15:05:20 +0000[diff] [blame]2268libxml2.debugMemory(1)</pre>
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]2269
2270<p>and ends with the following epilogue:</p>
2271<pre>#memory debug specific
2272libxml2.cleanupParser()
2273if libxml2.debugMemory(1) == 0:
2274 print "OK"
2275else:
2276 print "Memory leak %d bytes" % (libxml2.debugMemory(1))
2277 libxml2.dumpMemory()</pre>
2278
2279<p>Those activate the memory debugging interface of libxml2 where all
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]2280allocated block in the library are tracked. The prologue then cleans up the
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]2281library state and checks that all allocated memory has been freed. If not it
2282calls dumpMemory() which saves that list in a <code>.memdump</code> file.</p>
Daniel Veillard82687162001-01-22 15:32:01 +0000[diff] [blame]2283
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]2284<h2><a name="architecture">libxml2 architecture</a></h2>
Daniel Veillard4540be42000-08-19 16:40:28 +0000[diff] [blame]2285
Daniel Veillard560c2a42003-07-06 21:13:49 +0000[diff] [blame]2286<p>Libxml2 is made of multiple components; some of them are optional, and
2287most of the block interfaces are public. The main components are:</p>
Daniel Veillard4540be42000-08-19 16:40:28 +0000[diff] [blame]2288<ul>
2289 <li>an Input/Output layer</li>
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]2290 <li>FTP and HTTP client layers (optional)</li>
Daniel Veillard4540be42000-08-19 16:40:28 +0000[diff] [blame]2291 <li>an Internationalization layer managing the encodings support</li>
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]2292 <li>a URI module</li>
Daniel Veillard4540be42000-08-19 16:40:28 +0000[diff] [blame]2293 <li>the XML parser and its basic SAX interface</li>
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]2294 <li>an HTML parser using the same SAX interface (optional)</li>
Daniel Veillard4540be42000-08-19 16:40:28 +0000[diff] [blame]2295 <li>a SAX tree module to build an in-memory DOM representation</li>
2296 <li>a tree module to manipulate the DOM representation</li>
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]2297 <li>a validation module using the DOM representation (optional)</li>
Daniel Veillard4540be42000-08-19 16:40:28 +0000[diff] [blame]2298 <li>an XPath module for global lookup in a DOM representation
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]2299 (optional)</li>
2300 <li>a debug module (optional)</li>
Daniel Veillard4540be42000-08-19 16:40:28 +0000[diff] [blame]2301</ul>
2302
2303<p>Graphically this gives the following:</p>
2304
2305<p><img src="libxml.gif" alt="a graphical view of the various"></p>
2306
2307<p></p>
2308
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]2309<h2><a name="tree">The tree output</a></h2>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]2310
2311<p>The parser returns a tree built during the document analysis. The value
Daniel Veillard402e8c82000-02-29 22:57:47 +0000[diff] [blame]2312returned is an <strong>xmlDocPtr</strong> (i.e., a pointer to an
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]2313<strong>xmlDoc</strong> structure). This structure contains information such
Daniel Veillard306be992000-07-03 12:38:45 +0000[diff] [blame]2314as the file name, the document type, and a <strong>children</strong> pointer
2315which is the root of the document (or more exactly the first child under the
2316root which is the document). The tree is made of <strong>xmlNode</strong>s,
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]2317chained in double-linked lists of siblings and with a children&lt;-&gt;parent
Daniel Veillard306be992000-07-03 12:38:45 +0000[diff] [blame]2318relationship. An xmlNode can also carry properties (a chain of xmlAttr
2319structures). An attribute may have a value which is a list of TEXT or
2320ENTITY_REF nodes.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]2321
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]2322<p>Here is an example (erroneous with respect to the XML spec since there
2323should be only one ELEMENT under the root):</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]2324
2325<p><img src="structure.gif" alt=" structure.gif "></p>
2326
2327<p>In the source package there is a small program (not installed by default)
Daniel Veillard361d8452000-04-03 19:48:13 +0000[diff] [blame]2328called <strong>xmllint</strong> which parses XML files given as argument and
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]2329prints them back as parsed. This is useful for detecting errors both in XML
2330code and in the XML parser itself. It has an option <strong>--debug</strong>
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]2331which prints the actual in-memory structure of the document; here is the
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]2332result with the <a href="#example">example</a> given before:</p>
Daniel Veillard10c6a8f1998-10-28 01:00:12 +0000[diff] [blame]2333<pre>DOCUMENT
2334version=1.0
2335standalone=true
2336 ELEMENT EXAMPLE
2337 ATTRIBUTE prop1
2338 TEXT
2339 content=gnome is great
2340 ATTRIBUTE prop2
2341 ENTITY_REF
2342 TEXT
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]2343 content= linux too
Daniel Veillard402e8c82000-02-29 22:57:47 +0000[diff] [blame]2344 ELEMENT head
Daniel Veillard10c6a8f1998-10-28 01:00:12 +0000[diff] [blame]2345 ELEMENT title
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]2346 TEXT
2347 content=Welcome to Gnome
Daniel Veillard10c6a8f1998-10-28 01:00:12 +0000[diff] [blame]2348 ELEMENT chapter
2349 ELEMENT title
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]2350 TEXT
2351 content=The Linux adventure
Daniel Veillard10c6a8f1998-10-28 01:00:12 +0000[diff] [blame]2352 ELEMENT p
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]2353 TEXT
2354 content=bla bla bla ...
Daniel Veillard10c6a8f1998-10-28 01:00:12 +0000[diff] [blame]2355 ELEMENT image
2356 ATTRIBUTE href
2357 TEXT
2358 content=linus.gif
2359 ELEMENT p
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]2360 TEXT
2361 content=...</pre>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]2362
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]2363<p>This should be useful for learning the internal representation model.</p>
Daniel Veillardccb09631998-10-27 06:21:04 +0000[diff] [blame]2364
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]2365<h2><a name="interface">The SAX interface</a></h2>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]2366
Daniel Veillard402e8c82000-02-29 22:57:47 +0000[diff] [blame]2367<p>Sometimes the DOM tree output is just too large to fit reasonably into
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]2368memory. In that case (and if you don't expect to save back the XML document
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]2369loaded using libxml), it's better to use the SAX interface of libxml. SAX is
2370a <strong>callback-based interface</strong> to the parser. Before parsing,
2371the application layer registers a customized set of callbacks which are
2372called by the library as it progresses through the XML input.</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]2373
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]2374<p>To get more detailed step-by-step guidance on using the SAX interface of
Daniel Veillard4540be42000-08-19 16:40:28 +0000[diff] [blame]2375libxml, see the <a
2376href="http://www.daa.com.au/~james/gnome/xml-sax/xml-sax.html">nice
2377documentation</a>.written by <a href="mailto:james@daa.com.au">James
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]2378Henstridge</a>.</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]2379
2380<p>You can debug the SAX behaviour by using the <strong>testSAX</strong>
2381program located in the gnome-xml module (it's usually not shipped in the
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]2382binary packages of libxml, but you can find it in the tar source
Daniel Veillard402e8c82000-02-29 22:57:47 +0000[diff] [blame]2383distribution). Here is the sequence of callbacks that would be reported by
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]2384testSAX when parsing the example XML document shown earlier:</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]2385<pre>SAX.setDocumentLocator()
2386SAX.startDocument()
2387SAX.getEntity(amp)
2388SAX.startElement(EXAMPLE, prop1='gnome is great', prop2='&amp;amp; linux too')
2389SAX.characters( , 3)
2390SAX.startElement(head)
2391SAX.characters( , 4)
2392SAX.startElement(title)
2393SAX.characters(Welcome to Gnome, 16)
2394SAX.endElement(title)
2395SAX.characters( , 3)
2396SAX.endElement(head)
2397SAX.characters( , 3)
2398SAX.startElement(chapter)
2399SAX.characters( , 4)
2400SAX.startElement(title)
2401SAX.characters(The Linux adventure, 19)
2402SAX.endElement(title)
2403SAX.characters( , 4)
2404SAX.startElement(p)
2405SAX.characters(bla bla bla ..., 15)
2406SAX.endElement(p)
2407SAX.characters( , 4)
2408SAX.startElement(image, href='linus.gif')
2409SAX.endElement(image)
2410SAX.characters( , 4)
2411SAX.startElement(p)
2412SAX.characters(..., 3)
2413SAX.endElement(p)
2414SAX.characters( , 3)
2415SAX.endElement(chapter)
2416SAX.characters( , 1)
2417SAX.endElement(EXAMPLE)
2418SAX.endDocument()</pre>
2419
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]2420<p>Most of the other interfaces of libxml2 are based on the DOM tree-building
Daniel Veillardec70e912001-02-26 20:10:45 +0000[diff] [blame]2421facility, so nearly everything up to the end of this document presupposes the
2422use of the standard DOM tree build. Note that the DOM tree itself is built by
2423a set of registered default callbacks, without internal specific
2424interface.</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]2425
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2426<h2><a name="Validation">Validation &amp; DTDs</a></h2>
2427
2428<p>Table of Content:</p>
2429<ol>
2430 <li><a href="#General5">General overview</a></li>
2431 <li><a href="#definition">The definition</a></li>
2432 <li><a href="#Simple">Simple rules</a>
2433 <ol>
Daniel Veillard9c466822001-10-25 12:03:39 +0000[diff] [blame]2434 <li><a href="#reference">How to reference a DTD from a document</a></li>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2435 <li><a href="#Declaring">Declaring elements</a></li>
2436 <li><a href="#Declaring1">Declaring attributes</a></li>
2437 </ol>
2438 </li>
2439 <li><a href="#Some">Some examples</a></li>
2440 <li><a href="#validate">How to validate</a></li>
2441 <li><a href="#Other">Other resources</a></li>
2442</ol>
2443
2444<h3><a name="General5">General overview</a></h3>
2445
2446<p>Well what is validation and what is a DTD ?</p>
2447
2448<p>DTD is the acronym for Document Type Definition. This is a description of
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]2449the content for a family of XML files. This is part of the XML 1.0
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]2450specification, and allows one to describe and verify that a given document
2451instance conforms to the set of rules detailing its structure and content.</p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2452
2453<p>Validation is the process of checking a document against a DTD (more
2454generally against a set of construction rules).</p>
2455
2456<p>The validation process and building DTDs are the two most difficult parts
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]2457of the XML life cycle. Briefly a DTD defines all the possible elements to be
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2458found within your document, what is the formal shape of your document tree
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]2459(by defining the allowed content of an element; either text, a regular
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2460expression for the allowed list of children, or mixed content i.e. both text
Daniel Veillard42766c02002-08-22 20:52:17 +0000[diff] [blame]2461and children). The DTD also defines the valid attributes for all elements and
2462the types of those attributes.</p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2463
2464<h3><a name="definition1">The definition</a></h3>
2465
2466<p>The <a href="http://www.w3.org/TR/REC-xml">W3C XML Recommendation</a> (<a
2467href="http://www.xml.com/axml/axml.html">Tim Bray's annotated version of
2468Rev1</a>):</p>
2469<ul>
2470 <li><a href="http://www.w3.org/TR/REC-xml#elemdecls">Declaring
2471 elements</a></li>
2472 <li><a href="http://www.w3.org/TR/REC-xml#attdecls">Declaring
2473 attributes</a></li>
2474</ul>
2475
2476<p>(unfortunately) all this is inherited from the SGML world, the syntax is
2477ancient...</p>
2478
2479<h3><a name="Simple1">Simple rules</a></h3>
2480
Daniel Veillard42766c02002-08-22 20:52:17 +0000[diff] [blame]2481<p>Writing DTDs can be done in many ways. The rules to build them if you need
2482something permanent or something which can evolve over time can be radically
2483different. Really complex DTDs like DocBook ones are flexible but quite
2484harder to design. I will just focus on DTDs for a formats with a fixed simple
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2485structure. It is just a set of basic rules, and definitely not exhaustive nor
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]2486usable for complex DTD design.</p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2487
2488<h4><a name="reference1">How to reference a DTD from a document</a>:</h4>
2489
2490<p>Assuming the top element of the document is <code>spec</code> and the dtd
2491is placed in the file <code>mydtd</code> in the subdirectory
2492<code>dtds</code> of the directory from where the document were loaded:</p>
2493
2494<p><code>&lt;!DOCTYPE spec SYSTEM "dtds/mydtd"&gt;</code></p>
2495
2496<p>Notes:</p>
2497<ul>
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]2498 <li>The system string is actually an URI-Reference (as defined in <a
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2499 href="http://www.ietf.org/rfc/rfc2396.txt">RFC 2396</a>) so you can use a
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]2500 full URL string indicating the location of your DTD on the Web. This is a
2501 really good thing to do if you want others to validate your document.</li>
2502 <li>It is also possible to associate a <code>PUBLIC</code> identifier (a
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]2503 magic string) so that the DTD is looked up in catalogs on the client side
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]2504 without having to locate it on the web.</li>
2505 <li>A DTD contains a set of element and attribute declarations, but they
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]2506 don't define what the root of the document should be. This is explicitly
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2507 told to the parser/validator as the first element of the
2508 <code>DOCTYPE</code> declaration.</li>
2509</ul>
2510
2511<h4><a name="Declaring2">Declaring elements</a>:</h4>
2512
2513<p>The following declares an element <code>spec</code>:</p>
2514
2515<p><code>&lt;!ELEMENT spec (front, body, back?)&gt;</code></p>
2516
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]2517<p>It also expresses that the spec element contains one <code>front</code>,
Daniel Veillardc0801af2002-05-28 16:28:42 +0000[diff] [blame]2518one <code>body</code> and one optional <code>back</code> children elements in
2519this order. The declaration of one element of the structure and its content
2520are done in a single declaration. Similarly the following declares
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2521<code>div1</code> elements:</p>
2522
Daniel Veillard51737272002-01-23 23:10:38 +0000[diff] [blame]2523<p><code>&lt;!ELEMENT div1 (head, (p | list | note)*, div2?)&gt;</code></p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2524
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]2525<p>which means div1 contains one <code>head</code> then a series of optional
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2526<code>p</code>, <code>list</code>s and <code>note</code>s and then an
2527optional <code>div2</code>. And last but not least an element can contain
2528text:</p>
2529
2530<p><code>&lt;!ELEMENT b (#PCDATA)&gt;</code></p>
2531
2532<p><code>b</code> contains text or being of mixed content (text and elements
2533in no particular order):</p>
2534
2535<p><code>&lt;!ELEMENT p (#PCDATA|a|ul|b|i|em)*&gt;</code></p>
2536
2537<p><code>p </code>can contain text or <code>a</code>, <code>ul</code>,
2538<code>b</code>, <code>i </code>or <code>em</code> elements in no particular
2539order.</p>
2540
2541<h4><a name="Declaring1">Declaring attributes</a>:</h4>
2542
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]2543<p>Again the attributes declaration includes their content definition:</p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2544
2545<p><code>&lt;!ATTLIST termdef name CDATA #IMPLIED&gt;</code></p>
2546
2547<p>means that the element <code>termdef</code> can have a <code>name</code>
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]2548attribute containing text (<code>CDATA</code>) and which is optional
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2549(<code>#IMPLIED</code>). The attribute value can also be defined within a
2550set:</p>
2551
2552<p><code>&lt;!ATTLIST list type (bullets|ordered|glossary)
2553"ordered"&gt;</code></p>
2554
2555<p>means <code>list</code> element have a <code>type</code> attribute with 3
2556allowed values "bullets", "ordered" or "glossary" and which default to
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]2557"ordered" if the attribute is not explicitly specified.</p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2558
2559<p>The content type of an attribute can be text (<code>CDATA</code>),
2560anchor/reference/references
2561(<code>ID</code>/<code>IDREF</code>/<code>IDREFS</code>), entity(ies)
2562(<code>ENTITY</code>/<code>ENTITIES</code>) or name(s)
2563(<code>NMTOKEN</code>/<code>NMTOKENS</code>). The following defines that a
2564<code>chapter</code> element can have an optional <code>id</code> attribute
2565of type <code>ID</code>, usable for reference from attribute of type
2566IDREF:</p>
2567
2568<p><code>&lt;!ATTLIST chapter id ID #IMPLIED&gt;</code></p>
2569
2570<p>The last value of an attribute definition can be <code>#REQUIRED
2571</code>meaning that the attribute has to be given, <code>#IMPLIED</code>
2572meaning that it is optional, or the default value (possibly prefixed by
2573<code>#FIXED</code> if it is the only allowed).</p>
2574
2575<p>Notes:</p>
2576<ul>
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]2577 <li>Usually the attributes pertaining to a given element are declared in a
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2578 single expression, but it is just a convention adopted by a lot of DTD
2579 writers:
2580 <pre>&lt;!ATTLIST termdef
2581 id ID #REQUIRED
2582 name CDATA #IMPLIED&gt;</pre>
2583 <p>The previous construct defines both <code>id</code> and
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]2584 <code>name</code> attributes for the element <code>termdef</code>.</p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2585 </li>
2586</ul>
2587
2588<h3><a name="Some1">Some examples</a></h3>
2589
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]2590<p>The directory <code>test/valid/dtds/</code> in the libxml2 distribution
Daniel Veillard42766c02002-08-22 20:52:17 +0000[diff] [blame]2591contains some complex DTD examples. The example in the file
2592<code>test/valid/dia.xml</code> shows an XML file where the simple DTD is
2593directly included within the document.</p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2594
2595<h3><a name="validate1">How to validate</a></h3>
2596
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]2597<p>The simplest way is to use the xmllint program included with libxml. The
2598<code>--valid</code> option turns-on validation of the files given as input.
2599For example the following validates a copy of the first revision of the XML
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]26001.0 specification:</p>
2601
2602<p><code>xmllint --valid --noout test/valid/REC-xml-19980210.xml</code></p>
2603
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]2604<p>the -- noout is used to disable output of the resulting tree.</p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2605
Daniel Veillard42766c02002-08-22 20:52:17 +0000[diff] [blame]2606<p>The <code>--dtdvalid dtd</code> allows validation of the document(s)
2607against a given DTD.</p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2608
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]2609<p>Libxml2 exports an API to handle DTDs and validation, check the <a
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2610href="http://xmlsoft.org/html/libxml-valid.html">associated
2611description</a>.</p>
2612
2613<h3><a name="Other1">Other resources</a></h3>
2614
2615<p>DTDs are as old as SGML. So there may be a number of examples on-line, I
2616will just list one for now, others pointers welcome:</p>
2617<ul>
2618 <li><a href="http://www.xml101.com:8081/dtd/">XML-101 DTD</a></li>
2619</ul>
2620
2621<p>I suggest looking at the examples found under test/valid/dtd and any of
2622the large number of books available on XML. The dia example in test/valid
2623should be both simple and complete enough to allow you to build your own.</p>
2624
2625<p></p>
2626
2627<h2><a name="Memory">Memory Management</a></h2>
2628
2629<p>Table of Content:</p>
2630<ol>
2631 <li><a href="#General3">General overview</a></li>
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]2632 <li><a href="#setting">Setting libxml2 set of memory routines</a></li>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2633 <li><a href="#cleanup">Cleaning up after parsing</a></li>
2634 <li><a href="#Debugging">Debugging routines</a></li>
2635 <li><a href="#General4">General memory requirements</a></li>
2636</ol>
2637
2638<h3><a name="General3">General overview</a></h3>
2639
2640<p>The module <code><a
2641href="http://xmlsoft.org/html/libxml-xmlmemory.html">xmlmemory.h</a></code>
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]2642provides the interfaces to the libxml2 memory system:</p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2643<ul>
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]2644 <li>libxml2 does not use the libc memory allocator directly but xmlFree(),
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2645 xmlMalloc() and xmlRealloc()</li>
2646 <li>those routines can be reallocated to a specific set of routine, by
2647 default the libc ones i.e. free(), malloc() and realloc()</li>
2648 <li>the xmlmemory.c module includes a set of debugging routine</li>
2649</ul>
2650
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]2651<h3><a name="setting">Setting libxml2 set of memory routines</a></h3>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2652
2653<p>It is sometimes useful to not use the default memory allocator, either for
2654debugging, analysis or to implement a specific behaviour on memory management
2655(like on embedded systems). Two function calls are available to do so:</p>
2656<ul>
Daniel Veillardaf43f632002-03-08 15:05:20 +0000[diff] [blame]2657 <li><a href="http://xmlsoft.org/html/libxml-xmlmemory.html">xmlMemGet
2658 ()</a> which return the current set of functions in use by the parser</li>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2659 <li><a
2660 href="http://xmlsoft.org/html/libxml-xmlmemory.html">xmlMemSetup()</a>
Daniel Veillardaf43f632002-03-08 15:05:20 +0000[diff] [blame]2661 which allow to set up a new set of memory allocation functions</li>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2662</ul>
2663
2664<p>Of course a call to xmlMemSetup() should probably be done before calling
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]2665any other libxml2 routines (unless you are sure your allocations routines are
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2666compatibles).</p>
2667
2668<h3><a name="cleanup">Cleaning up after parsing</a></h3>
2669
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]2670<p>Libxml2 is not stateless, there is a few set of memory structures needing
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]2671allocation before the parser is fully functional (some encoding structures
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2672for example). This also mean that once parsing is finished there is a tiny
2673amount of memory (a few hundred bytes) which can be recollected if you don't
2674reuse the parser immediately:</p>
2675<ul>
2676 <li><a href="http://xmlsoft.org/html/libxml-parser.html">xmlCleanupParser
Daniel Veillardaf43f632002-03-08 15:05:20 +0000[diff] [blame]2677 ()</a> is a centralized routine to free the parsing states. Note that it
2678 won't deallocate any produced tree if any (use the xmlFreeDoc() and
2679 related routines for this).</li>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2680 <li><a href="http://xmlsoft.org/html/libxml-parser.html">xmlInitParser
Daniel Veillardaf43f632002-03-08 15:05:20 +0000[diff] [blame]2681 ()</a> is the dual routine allowing to preallocate the parsing state
2682 which can be useful for example to avoid initialization reentrancy
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]2683 problems when using libxml2 in multithreaded applications</li>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2684</ul>
2685
2686<p>Generally xmlCleanupParser() is safe, if needed the state will be rebuild
2687at the next invocation of parser routines, but be careful of the consequences
2688in multithreaded applications.</p>
2689
2690<h3><a name="Debugging">Debugging routines</a></h3>
2691
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]2692<p>When configured using --with-mem-debug flag (off by default), libxml2 uses
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]2693a set of memory allocation debugging routines keeping track of all allocated
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2694blocks and the location in the code where the routine was called. A couple of
2695other debugging routines allow to dump the memory allocated infos to a file
2696or call a specific routine when a given block number is allocated:</p>
2697<ul>
2698 <li><a
2699 href="http://xmlsoft.org/html/libxml-xmlmemory.html">xmlMallocLoc()</a>
Daniel Veillardaf43f632002-03-08 15:05:20 +0000[diff] [blame]2700 <a
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2701 href="http://xmlsoft.org/html/libxml-xmlmemory.html">xmlReallocLoc()</a>
2702 and <a
2703 href="http://xmlsoft.org/html/libxml-xmlmemory.html">xmlMemStrdupLoc()</a>
2704 are the memory debugging replacement allocation routines</li>
2705 <li><a href="http://xmlsoft.org/html/libxml-xmlmemory.html">xmlMemoryDump
Daniel Veillardaf43f632002-03-08 15:05:20 +0000[diff] [blame]2706 ()</a> dumps all the informations about the allocated memory block lefts
2707 in the <code>.memdump</code> file</li>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2708</ul>
2709
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]2710<p>When developing libxml2 memory debug is enabled, the tests programs call
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2711xmlMemoryDump () and the "make test" regression tests will check for any
2712memory leak during the full regression test sequence, this helps a lot
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]2713ensuring that libxml2 does not leak memory and bullet proof memory
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2714allocations use (some libc implementations are known to be far too permissive
2715resulting in major portability problems!).</p>
2716
2717<p>If the .memdump reports a leak, it displays the allocation function and
2718also tries to give some informations about the content and structure of the
2719allocated blocks left. This is sufficient in most cases to find the culprit,
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]2720but not always. Assuming the allocation problem is reproducible, it is
2721possible to find more easily:</p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2722<ol>
2723 <li>write down the block number xxxx not allocated</li>
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]2724 <li>export the environment variable XML_MEM_BREAKPOINT=xxxx , the easiest
Daniel Veillard75794822002-04-11 16:24:32 +0000[diff] [blame]2725 when using GDB is to simply give the command
2726 <p><code>set environment XML_MEM_BREAKPOINT xxxx</code></p>
2727 <p>before running the program.</p>
2728 </li>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2729 <li>run the program under a debugger and set a breakpoint on
2730 xmlMallocBreakpoint() a specific function called when this precise block
2731 is allocated</li>
2732 <li>when the breakpoint is reached you can then do a fine analysis of the
2733 allocation an step to see the condition resulting in the missing
2734 deallocation.</li>
2735</ol>
2736
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]2737<p>I used to use a commercial tool to debug libxml2 memory problems but after
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2738noticing that it was not detecting memory leaks that simple mechanism was
Daniel Veillard75794822002-04-11 16:24:32 +0000[diff] [blame]2739used and proved extremely efficient until now. Lately I have also used <a
2740href="http://developer.kde.org/~sewardj/">valgrind</a> with quite some
2741success, it is tied to the i386 architecture since it works by emulating the
2742processor and instruction set, it is slow but extremely efficient, i.e. it
2743spot memory usage errors in a very precise way.</p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2744
2745<h3><a name="General4">General memory requirements</a></h3>
2746
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]2747<p>How much libxml2 memory require ? It's hard to tell in average it depends
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2748of a number of things:</p>
2749<ul>
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]2750 <li>the parser itself should work in a fixed amount of memory, except for
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2751 information maintained about the stacks of names and entities locations.
2752 The I/O and encoding handlers will probably account for a few KBytes.
2753 This is true for both the XML and HTML parser (though the HTML parser
2754 need more state).</li>
2755 <li>If you are generating the DOM tree then memory requirements will grow
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]2756 nearly linear with the size of the data. In general for a balanced
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2757 textual document the internal memory requirement is about 4 times the
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]2758 size of the UTF8 serialization of this document (example the XML-1.0
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2759 recommendation is a bit more of 150KBytes and takes 650KBytes of main
2760 memory when parsed). Validation will add a amount of memory required for
2761 maintaining the external Dtd state which should be linear with the
2762 complexity of the content model defined by the Dtd</li>
Daniel Veillardce192eb2003-04-16 15:58:05 +0000[diff] [blame]2763 <li>If you need to work with fixed memory requirements or don't need the
2764 full DOM tree then using the <a href="xmlreader.html">xmlReader
2765 interface</a> is probably the best way to proceed, it still allows to
2766 validate or operate on subset of the tree if needed.</li>
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]2767 <li>If you don't care about the advanced features of libxml2 like
Daniel Veillardce192eb2003-04-16 15:58:05 +0000[diff] [blame]2768 validation, DOM, XPath or XPointer, don't use entities, need to work with
2769 fixed memory requirements, and try to get the fastest parsing possible
2770 then the SAX interface should be used, but it has known restrictions.</li>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2771</ul>
2772
2773<p></p>
2774
2775<h2><a name="Encodings">Encodings support</a></h2>
2776
2777<p>Table of Content:</p>
2778<ol>
2779 <li><a href="encoding.html#What">What does internationalization support
2780 mean ?</a></li>
2781 <li><a href="encoding.html#internal">The internal encoding, how and
2782 why</a></li>
2783 <li><a href="encoding.html#implemente">How is it implemented ?</a></li>
2784 <li><a href="encoding.html#Default">Default supported encodings</a></li>
2785 <li><a href="encoding.html#extend">How to extend the existing
2786 support</a></li>
2787</ol>
2788
2789<h3><a name="What">What does internationalization support mean ?</a></h3>
2790
Daniel Veillarde6e59cd2003-12-24 11:56:44 +0000[diff] [blame]2791<p>If you are not really familiar with Internationalization (usual shortcut
2792is I18N) , Unicode, characters and glyphs, I suggest you read a <a
Daniel Veillard238836e2003-04-07 22:57:29 +0000[diff] [blame]2793href="http://www.tbray.org/ongoing/When/200x/2003/04/06/Unicode">presentation</a>
2794by Tim Bray on Unicode and why you should care about it.</p>
2795
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2796<p>XML was designed from the start to allow the support of any character set
2797by using Unicode. Any conformant XML parser has to support the UTF-8 and
2798UTF-16 default encodings which can both express the full unicode ranges. UTF8
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]2799is a variable length encoding whose greatest points are to reuse the same
2800encoding for ASCII and to save space for Western encodings, but it is a bit
Daniel Veillardabfca612004-01-07 23:38:02 +0000[diff] [blame]2801more complex to handle in practice. UTF-16 use 2 bytes per character (and
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2802sometimes combines two pairs), it makes implementation easier, but looks a
2803bit overkill for Western languages encoding. Moreover the XML specification
Daniel Veillard189f46b2004-01-25 21:03:04 +0000[diff] [blame^]2804allows the document to be encoded in other encodings at the condition that
2805they are clearly labeled as such. For example the following is a wellformed
2806XML document encoded in ISO-8859-1 and using accentuated letters that we
2807French like for both markup and content:</p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2808<pre>&lt;?xml version="1.0" encoding="ISO-8859-1"?&gt;
2809&lt;très&gt;là&lt;/très&gt;</pre>
2810
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]2811<p>Having internationalization support in libxml2 means the following:</p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2812<ul>
2813 <li>the document is properly parsed</li>
2814 <li>informations about it's encoding are saved</li>
2815 <li>it can be modified</li>
2816 <li>it can be saved in its original encoding</li>
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]2817 <li>it can also be saved in another encoding supported by libxml2 (for
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2818 example straight UTF8 or even an ASCII form)</li>
2819</ul>
2820
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]2821<p>Another very important point is that the whole libxml2 API, with the
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2822exception of a few routines to read with a specific encoding or save to a
2823specific encoding, is completely agnostic about the original encoding of the
2824document.</p>
2825
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]2826<p>It should be noted too that the HTML parser embedded in libxml2 now obey
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2827the same rules too, the following document will be (as of 2.2.2) handled in
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]2828an internationalized fashion by libxml2 too:</p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2829<pre>&lt;!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"
2830 "http://www.w3.org/TR/REC-html40/loose.dtd"&gt;
2831&lt;html lang="fr"&gt;
2832&lt;head&gt;
2833 &lt;META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=ISO-8859-1"&gt;
2834&lt;/head&gt;
2835&lt;body&gt;
2836&lt;p&gt;W3C crée des standards pour le Web.&lt;/body&gt;
2837&lt;/html&gt;</pre>
2838
2839<h3><a name="internal">The internal encoding, how and why</a></h3>
2840
Daniel Veillardabfca612004-01-07 23:38:02 +0000[diff] [blame]2841<p>One of the core decisions was to force all documents to be converted to a
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2842default internal encoding, and that encoding to be UTF-8, here are the
Daniel Veillardabfca612004-01-07 23:38:02 +0000[diff] [blame]2843rationales for those choices:</p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2844<ul>
2845 <li>keeping the native encoding in the internal form would force the libxml
2846 users (or the code associated) to be fully aware of the encoding of the
2847 original document, for examples when adding a text node to a document,
2848 the content would have to be provided in the document encoding, i.e. the
2849 client code would have to check it before hand, make sure it's conformant
2850 to the encoding, etc ... Very hard in practice, though in some specific
2851 cases this may make sense.</li>
2852 <li>the second decision was which encoding. From the XML spec only UTF8 and
2853 UTF16 really makes sense as being the two only encodings for which there
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]2854 is mandatory support. UCS-4 (32 bits fixed size encoding) could be
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2855 considered an intelligent choice too since it's a direct Unicode mapping
2856 support. I selected UTF-8 on the basis of efficiency and compatibility
2857 with surrounding software:
2858 <ul>
2859 <li>UTF-8 while a bit more complex to convert from/to (i.e. slightly
2860 more costly to import and export CPU wise) is also far more compact
2861 than UTF-16 (and UCS-4) for a majority of the documents I see it used
2862 for right now (RPM RDF catalogs, advogato data, various configuration
2863 file formats, etc.) and the key point for today's computer
2864 architecture is efficient uses of caches. If one nearly double the
2865 memory requirement to store the same amount of data, this will trash
2866 caches (main memory/external caches/internal caches) and my take is
2867 that this harms the system far more than the CPU requirements needed
2868 for the conversion to UTF-8</li>
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]2869 <li>Most of libxml2 version 1 users were using it with straight ASCII
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2870 most of the time, doing the conversion with an internal encoding
2871 requiring all their code to be rewritten was a serious show-stopper
2872 for using UTF-16 or UCS-4.</li>
2873 <li>UTF-8 is being used as the de-facto internal encoding standard for
2874 related code like the <a href="http://www.pango.org/">pango</a>
Daniel Veillardabfca612004-01-07 23:38:02 +0000[diff] [blame]2875 upcoming Gnome text widget, and a lot of Unix code (yet another place
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2876 where Unix programmer base takes a different approach from Microsoft
2877 - they are using UTF-16)</li>
2878 </ul>
2879 </li>
2880</ul>
2881
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]2882<p>What does this mean in practice for the libxml2 user:</p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2883<ul>
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]2884 <li>xmlChar, the libxml2 data type is a byte, those bytes must be assembled
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2885 as UTF-8 valid strings. The proper way to terminate an xmlChar * string
2886 is simply to append 0 byte, as usual.</li>
2887 <li>One just need to make sure that when using chars outside the ASCII set,
2888 the values has been properly converted to UTF-8</li>
2889</ul>
2890
2891<h3><a name="implemente">How is it implemented ?</a></h3>
2892
2893<p>Let's describe how all this works within libxml, basically the I18N
2894(internationalization) support get triggered only during I/O operation, i.e.
2895when reading a document or saving one. Let's look first at the reading
2896sequence:</p>
2897<ol>
2898 <li>when a document is processed, we usually don't know the encoding, a
Daniel Veillard189f46b2004-01-25 21:03:04 +0000[diff] [blame^]2899 simple heuristic allows to detect UTF-16 and UCS-4 from encodings where
2900 the ASCII range (0-0x7F) maps with ASCII</li>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2901 <li>the xml declaration if available is parsed, including the encoding
2902 declaration. At that point, if the autodetected encoding is different
2903 from the one declared a call to xmlSwitchEncoding() is issued.</li>
2904 <li>If there is no encoding declaration, then the input has to be in either
2905 UTF-8 or UTF-16, if it is not then at some point when processing the
2906 input, the converter/checker of UTF-8 form will raise an encoding error.
2907 You may end-up with a garbled document, or no document at all ! Example:
2908 <pre>~/XML -&gt; ./xmllint err.xml
2909err.xml:1: error: Input is not proper UTF-8, indicate encoding !
2910&lt;très&gt;là&lt;/très&gt;
2911 ^
2912err.xml:1: error: Bytes: 0xE8 0x73 0x3E 0x6C
2913&lt;très&gt;là&lt;/très&gt;
2914 ^</pre>
2915 </li>
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]2916 <li>xmlSwitchEncoding() does an encoding name lookup, canonicalize it, and
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2917 then search the default registered encoding converters for that encoding.
2918 If it's not within the default set and iconv() support has been compiled
2919 it, it will ask iconv for such an encoder. If this fails then the parser
2920 will report an error and stops processing:
2921 <pre>~/XML -&gt; ./xmllint err2.xml
2922err2.xml:1: error: Unsupported encoding UnsupportedEnc
2923&lt;?xml version="1.0" encoding="UnsupportedEnc"?&gt;
2924 ^</pre>
2925 </li>
Daniel Veillard46c5c1d2002-05-20 07:15:54 +0000[diff] [blame]2926 <li>From that point the encoder processes progressively the input (it is
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2927 plugged as a front-end to the I/O module) for that entity. It captures
Daniel Veillardabfca612004-01-07 23:38:02 +0000[diff] [blame]2928 and converts on-the-fly the document to be parsed to UTF-8. The parser
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2929 itself just does UTF-8 checking of this input and process it
2930 transparently. The only difference is that the encoding information has
2931 been added to the parsing context (more precisely to the input
2932 corresponding to this entity).</li>
2933 <li>The result (when using DOM) is an internal form completely in UTF-8
2934 with just an encoding information on the document node.</li>
2935</ol>
2936
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]2937<p>Ok then what happens when saving the document (assuming you
2938collected/built an xmlDoc DOM like structure) ? It depends on the function
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2939called, xmlSaveFile() will just try to save in the original encoding, while
2940xmlSaveFileTo() and xmlSaveFileEnc() can optionally save to a given
2941encoding:</p>
2942<ol>
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]2943 <li>if no encoding is given, libxml2 will look for an encoding value
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2944 associated to the document and if it exists will try to save to that
2945 encoding,
2946 <p>otherwise everything is written in the internal form, i.e. UTF-8</p>
2947 </li>
2948 <li>so if an encoding was specified, either at the API level or on the
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]2949 document, libxml2 will again canonicalize the encoding name, lookup for a
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2950 converter in the registered set or through iconv. If not found the
2951 function will return an error code</li>
2952 <li>the converter is placed before the I/O buffer layer, as another kind of
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]2953 buffer, then libxml2 will simply push the UTF-8 serialization to through
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2954 that buffer, which will then progressively be converted and pushed onto
2955 the I/O layer.</li>
2956 <li>It is possible that the converter code fails on some input, for example
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]2957 trying to push an UTF-8 encoded Chinese character through the UTF-8 to
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2958 ISO-8859-1 converter won't work. Since the encoders are progressive they
2959 will just report the error and the number of bytes converted, at that
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]2960 point libxml2 will decode the offending character, remove it from the
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2961 buffer and replace it with the associated charRef encoding &amp;#123; and
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]2962 resume the conversion. This guarantees that any document will be saved
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2963 without losses (except for markup names where this is not legal, this is
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]2964 a problem in the current version, in practice avoid using non-ascii
Daniel Veillard189f46b2004-01-25 21:03:04 +0000[diff] [blame^]2965 characters for tag or attribute names). A special "ascii" encoding name
2966 is used to save documents to a pure ascii form can be used when
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2967 portability is really crucial</li>
2968</ol>
2969
Daniel Veillardabfca612004-01-07 23:38:02 +0000[diff] [blame]2970<p>Here are a few examples based on the same test document:</p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2971<pre>~/XML -&gt; ./xmllint isolat1
2972&lt;?xml version="1.0" encoding="ISO-8859-1"?&gt;
2973&lt;très&gt;là&lt;/très&gt;
2974~/XML -&gt; ./xmllint --encode UTF-8 isolat1
2975&lt;?xml version="1.0" encoding="UTF-8"?&gt;
2976&lt;très&gt;là  &lt;/très&gt;
2977~/XML -&gt; </pre>
2978
2979<p>The same processing is applied (and reuse most of the code) for HTML I18N
2980processing. Looking up and modifying the content encoding is a bit more
2981difficult since it is located in a &lt;meta&gt; tag under the &lt;head&gt;,
2982so a couple of functions htmlGetMetaEncoding() and htmlSetMetaEncoding() have
2983been provided. The parser also attempts to switch encoding on the fly when
2984detecting such a tag on input. Except for that the processing is the same
2985(and again reuses the same code).</p>
2986
2987<h3><a name="Default">Default supported encodings</a></h3>
2988
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]2989<p>libxml2 has a set of default converters for the following encodings
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2990(located in encoding.c):</p>
2991<ol>
2992 <li>UTF-8 is supported by default (null handlers)</li>
2993 <li>UTF-16, both little and big endian</li>
2994 <li>ISO-Latin-1 (ISO-8859-1) covering most western languages</li>
2995 <li>ASCII, useful mostly for saving</li>
2996 <li>HTML, a specific handler for the conversion of UTF-8 to ASCII with HTML
2997 predefined entities like &amp;copy; for the Copyright sign.</li>
2998</ol>
2999
Daniel Veillardc0801af2002-05-28 16:28:42 +0000[diff] [blame]3000<p>More over when compiled on an Unix platform with iconv support the full
3001set of encodings supported by iconv can be instantly be used by libxml. On a
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]3002linux machine with glibc-2.1 the list of supported encodings and aliases fill
30033 full pages, and include UCS-4, the full set of ISO-Latin encodings, and the
3004various Japanese ones.</p>
3005
3006<h4>Encoding aliases</h4>
3007
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]3008<p>From 2.2.3, libxml2 has support to register encoding names aliases. The
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]3009goal is to be able to parse document whose encoding is supported but where
3010the name differs (for example from the default set of names accepted by
3011iconv). The following functions allow to register and handle new aliases for
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]3012existing encodings. Once registered libxml2 will automatically lookup the
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]3013aliases when handling a document:</p>
3014<ul>
3015 <li>int xmlAddEncodingAlias(const char *name, const char *alias);</li>
3016 <li>int xmlDelEncodingAlias(const char *alias);</li>
3017 <li>const char * xmlGetEncodingAlias(const char *alias);</li>
3018 <li>void xmlCleanupEncodingAliases(void);</li>
3019</ul>
3020
3021<h3><a name="extend">How to extend the existing support</a></h3>
3022
3023<p>Well adding support for new encoding, or overriding one of the encoders
Daniel Veillardabfca612004-01-07 23:38:02 +0000[diff] [blame]3024(assuming it is buggy) should not be hard, just write input and output
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]3025conversion routines to/from UTF-8, and register them using
3026xmlNewCharEncodingHandler(name, xxxToUTF8, UTF8Toxxx), and they will be
3027called automatically if the parser(s) encounter such an encoding name
3028(register it uppercase, this will help). The description of the encoders,
3029their arguments and expected return values are described in the encoding.h
3030header.</p>
3031
3032<p>A quick note on the topic of subverting the parser to use a different
3033internal encoding than UTF-8, in some case people will absolutely want to
3034keep the internal encoding different, I think it's still possible (but the
3035encoding must be compliant with ASCII on the same subrange) though I didn't
3036tried it. The key is to override the default conversion routines (by
3037registering null encoders/decoders for your charsets), and bypass the UTF-8
3038checking of the parser by setting the parser context charset
3039(ctxt-&gt;charset) to something different than XML_CHAR_ENCODING_UTF8, but
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]3040there is no guarantee that this will work. You may also have some troubles
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]3041saving back.</p>
3042
3043<p>Basically proper I18N support is important, this requires at least
3044libxml-2.0.0, but a lot of features and corrections are really available only
3045starting 2.2.</p>
3046
3047<h2><a name="IO">I/O Interfaces</a></h2>
3048
3049<p>Table of Content:</p>
3050<ol>
3051 <li><a href="#General1">General overview</a></li>
3052 <li><a href="#basic">The basic buffer type</a></li>
3053 <li><a href="#Input">Input I/O handlers</a></li>
3054 <li><a href="#Output">Output I/O handlers</a></li>
3055 <li><a href="#entities">The entities loader</a></li>
3056 <li><a href="#Example2">Example of customized I/O</a></li>
3057</ol>
3058
3059<h3><a name="General1">General overview</a></h3>
3060
3061<p>The module <code><a
3062href="http://xmlsoft.org/html/libxml-xmlio.html">xmlIO.h</a></code> provides
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]3063the interfaces to the libxml2 I/O system. This consists of 4 main parts:</p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]3064<ul>
3065 <li>Entities loader, this is a routine which tries to fetch the entities
3066 (files) based on their PUBLIC and SYSTEM identifiers. The default loader
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]3067 don't look at the public identifier since libxml2 do not maintain a
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]3068 catalog. You can redefine you own entity loader by using
3069 <code>xmlGetExternalEntityLoader()</code> and
Daniel Veillard9c466822001-10-25 12:03:39 +0000[diff] [blame]3070 <code>xmlSetExternalEntityLoader()</code>. <a href="#entities">Check the
3071 example</a>.</li>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]3072 <li>Input I/O buffers which are a commodity structure used by the parser(s)
3073 input layer to handle fetching the informations to feed the parser. This
3074 provides buffering and is also a placeholder where the encoding
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]3075 converters to UTF8 are piggy-backed.</li>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]3076 <li>Output I/O buffers are similar to the Input ones and fulfill similar
3077 task but when generating a serialization from a tree.</li>
3078 <li>A mechanism to register sets of I/O callbacks and associate them with
3079 specific naming schemes like the protocol part of the URIs.
3080 <p>This affect the default I/O operations and allows to use specific I/O
3081 handlers for certain names.</p>
3082 </li>
3083</ul>
3084
3085<p>The general mechanism used when loading http://rpmfind.net/xml.html for
3086example in the HTML parser is the following:</p>
3087<ol>
3088 <li>The default entity loader calls <code>xmlNewInputFromFile()</code> with
3089 the parsing context and the URI string.</li>
3090 <li>the URI string is checked against the existing registered handlers
3091 using their match() callback function, if the HTTP module was compiled
3092 in, it is registered and its match() function will succeeds</li>
3093 <li>the open() function of the handler is called and if successful will
3094 return an I/O Input buffer</li>
3095 <li>the parser will the start reading from this buffer and progressively
3096 fetch information from the resource, calling the read() function of the
3097 handler until the resource is exhausted</li>
3098 <li>if an encoding change is detected it will be installed on the input
3099 buffer, providing buffering and efficient use of the conversion
3100 routines</li>
3101 <li>once the parser has finished, the close() function of the handler is
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]3102 called once and the Input buffer and associated resources are
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]3103 deallocated.</li>
3104</ol>
3105
3106<p>The user defined callbacks are checked first to allow overriding of the
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]3107default libxml2 I/O routines.</p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]3108
3109<h3><a name="basic">The basic buffer type</a></h3>
3110
3111<p>All the buffer manipulation handling is done using the
3112<code>xmlBuffer</code> type define in <code><a
3113href="http://xmlsoft.org/html/libxml-tree.html">tree.h</a> </code>which is a
3114resizable memory buffer. The buffer allocation strategy can be selected to be
3115either best-fit or use an exponential doubling one (CPU vs. memory use
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]3116trade-off). The values are <code>XML_BUFFER_ALLOC_EXACT</code> and
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]3117<code>XML_BUFFER_ALLOC_DOUBLEIT</code>, and can be set individually or on a
3118system wide basis using <code>xmlBufferSetAllocationScheme()</code>. A number
3119of functions allows to manipulate buffers with names starting with the
3120<code>xmlBuffer...</code> prefix.</p>
3121
3122<h3><a name="Input">Input I/O handlers</a></h3>
3123
3124<p>An Input I/O handler is a simple structure
3125<code>xmlParserInputBuffer</code> containing a context associated to the
3126resource (file descriptor, or pointer to a protocol handler), the read() and
3127close() callbacks to use and an xmlBuffer. And extra xmlBuffer and a charset
3128encoding handler are also present to support charset conversion when
3129needed.</p>
3130
3131<h3><a name="Output">Output I/O handlers</a></h3>
3132
3133<p>An Output handler <code>xmlOutputBuffer</code> is completely similar to an
3134Input one except the callbacks are write() and close().</p>
3135
3136<h3><a name="entities">The entities loader</a></h3>
3137
3138<p>The entity loader resolves requests for new entities and create inputs for
3139the parser. Creating an input from a filename or an URI string is done
3140through the xmlNewInputFromFile() routine. The default entity loader do not
3141handle the PUBLIC identifier associated with an entity (if any). So it just
3142calls xmlNewInputFromFile() with the SYSTEM identifier (which is mandatory in
3143XML).</p>
3144
3145<p>If you want to hook up a catalog mechanism then you simply need to
3146override the default entity loader, here is an example:</p>
3147<pre>#include &lt;libxml/xmlIO.h&gt;
3148
3149xmlExternalEntityLoader defaultLoader = NULL;
3150
3151xmlParserInputPtr
3152xmlMyExternalEntityLoader(const char *URL, const char *ID,
3153 xmlParserCtxtPtr ctxt) {
3154 xmlParserInputPtr ret;
3155 const char *fileID = NULL;
3156 /* lookup for the fileID depending on ID */
3157
3158 ret = xmlNewInputFromFile(ctxt, fileID);
3159 if (ret != NULL)
3160 return(ret);
3161 if (defaultLoader != NULL)
3162 ret = defaultLoader(URL, ID, ctxt);
3163 return(ret);
3164}
3165
3166int main(..) {
3167 ...
3168
3169 /*
3170 * Install our own entity loader
3171 */
3172 defaultLoader = xmlGetExternalEntityLoader();
3173 xmlSetExternalEntityLoader(xmlMyExternalEntityLoader);
3174
3175 ...
3176}</pre>
3177
3178<h3><a name="Example2">Example of customized I/O</a></h3>
3179
3180<p>This example come from <a href="http://xmlsoft.org/messages/0708.html">a
3181real use case</a>, xmlDocDump() closes the FILE * passed by the application
3182and this was a problem. The <a
3183href="http://xmlsoft.org/messages/0711.html">solution</a> was to redefine a
3184new output handler with the closing call deactivated:</p>
3185<ol>
Daniel Veillardc0801af2002-05-28 16:28:42 +0000[diff] [blame]3186 <li>First define a new I/O output allocator where the output don't close
3187 the file:
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]3188 <pre>xmlOutputBufferPtr
3189xmlOutputBufferCreateOwn(FILE *file, xmlCharEncodingHandlerPtr encoder) {
3190    xmlOutputBufferPtr ret;
3191    
3192    if (xmlOutputCallbackInitialized == 0)
3193        xmlRegisterDefaultOutputCallbacks();
3194
3195    if (file == NULL) return(NULL);
3196    ret = xmlAllocOutputBuffer(encoder);
3197    if (ret != NULL) {
3198        ret-&gt;context = file;
3199        ret-&gt;writecallback = xmlFileWrite;
3200        ret-&gt;closecallback = NULL; /* No close callback */
3201    }
Daniel Veillardf83a2c72003-04-08 13:48:40 +0000[diff] [blame]3202    return(ret);
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]3203} </pre>
3204 </li>
3205 <li>And then use it to save the document:
3206 <pre>FILE *f;
3207xmlOutputBufferPtr output;
3208xmlDocPtr doc;
3209int res;
3210
3211f = ...
3212doc = ....
3213
3214output = xmlOutputBufferCreateOwn(f, NULL);
3215res = xmlSaveFileTo(output, doc, NULL);
3216 </pre>
3217 </li>
3218</ol>
3219
3220<h2><a name="Catalog">Catalog support</a></h2>
3221
3222<p>Table of Content:</p>
3223<ol>
3224 <li><a href="General2">General overview</a></li>
3225 <li><a href="#definition">The definition</a></li>
3226 <li><a href="#Simple">Using catalogs</a></li>
3227 <li><a href="#Some">Some examples</a></li>
3228 <li><a href="#reference">How to tune catalog usage</a></li>
3229 <li><a href="#validate">How to debug catalog processing</a></li>
3230 <li><a href="#Declaring">How to create and maintain catalogs</a></li>
3231 <li><a href="#implemento">The implementor corner quick review of the
3232 API</a></li>
3233 <li><a href="#Other">Other resources</a></li>
3234</ol>
3235
3236<h3><a name="General2">General overview</a></h3>
3237
3238<p>What is a catalog? Basically it's a lookup mechanism used when an entity
3239(a file or a remote resource) references another entity. The catalog lookup
3240is inserted between the moment the reference is recognized by the software
3241(XML parser, stylesheet processing, or even images referenced for inclusion
3242in a rendering) and the time where loading that resource is actually
3243started.</p>
3244
3245<p>It is basically used for 3 things:</p>
3246<ul>
3247 <li>mapping from "logical" names, the public identifiers and a more
3248 concrete name usable for download (and URI). For example it can associate
3249 the logical name
3250 <p>"-//OASIS//DTD DocBook XML V4.1.2//EN"</p>
3251 <p>of the DocBook 4.1.2 XML DTD with the actual URL where it can be
3252 downloaded</p>
3253 <p>http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd</p>
3254 </li>
3255 <li>remapping from a given URL to another one, like an HTTP indirection
3256 saying that
3257 <p>"http://www.oasis-open.org/committes/tr.xsl"</p>
3258 <p>should really be looked at</p>
3259 <p>"http://www.oasis-open.org/committes/entity/stylesheets/base/tr.xsl"</p>
3260 </li>
3261 <li>providing a local cache mechanism allowing to load the entities
3262 associated to public identifiers or remote resources, this is a really
3263 important feature for any significant deployment of XML or SGML since it
3264 allows to avoid the aleas and delays associated to fetching remote
3265 resources.</li>
3266</ul>
3267
3268<h3><a name="definition">The definitions</a></h3>
3269
3270<p>Libxml, as of 2.4.3 implements 2 kind of catalogs:</p>
3271<ul>
3272 <li>the older SGML catalogs, the official spec is SGML Open Technical
3273 Resolution TR9401:1997, but is better understood by reading <a
3274 href="http://www.jclark.com/sp/catalog.htm">the SP Catalog page</a> from
3275 James Clark. This is relatively old and not the preferred mode of
3276 operation of libxml.</li>
3277 <li><a href="http://www.oasis-open.org/committees/entity/spec.html">XML
Daniel Veillardaf43f632002-03-08 15:05:20 +0000[diff] [blame]3278 Catalogs</a> is far more flexible, more recent, uses an XML syntax and
3279 should scale quite better. This is the default option of libxml.</li>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]3280</ul>
3281
3282<p></p>
3283
3284<h3><a name="Simple">Using catalog</a></h3>
3285
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]3286<p>In a normal environment libxml2 will by default check the presence of a
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]3287catalog in /etc/xml/catalog, and assuming it has been correctly populated,
3288the processing is completely transparent to the document user. To take a
3289concrete example, suppose you are authoring a DocBook document, this one
3290starts with the following DOCTYPE definition:</p>
3291<pre>&lt;?xml version='1.0'?&gt;
3292&lt;!DOCTYPE book PUBLIC "-//Norman Walsh//DTD DocBk XML V3.1.4//EN"
3293 "http://nwalsh.com/docbook/xml/3.1.4/db3xml.dtd"&gt;</pre>
3294
3295<p>When validating the document with libxml, the catalog will be
3296automatically consulted to lookup the public identifier "-//Norman Walsh//DTD
3297DocBk XML V3.1.4//EN" and the system identifier
3298"http://nwalsh.com/docbook/xml/3.1.4/db3xml.dtd", and if these entities have
3299been installed on your system and the catalogs actually point to them, libxml
3300will fetch them from the local disk.</p>
3301
3302<p style="font-size: 10pt"><strong>Note</strong>: Really don't use this
3303DOCTYPE example it's a really old version, but is fine as an example.</p>
3304
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]3305<p>Libxml2 will check the catalog each time that it is requested to load an
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]3306entity, this includes DTD, external parsed entities, stylesheets, etc ... If
3307your system is correctly configured all the authoring phase and processing
3308should use only local files, even if your document stays portable because it
3309uses the canonical public and system ID, referencing the remote document.</p>
3310
3311<h3><a name="Some">Some examples:</a></h3>
3312
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]3313<p>Here is a couple of fragments from XML Catalogs used in libxml2 early
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]3314regression tests in <code>test/catalogs</code> :</p>
3315<pre>&lt;?xml version="1.0"?&gt;
3316&lt;!DOCTYPE catalog PUBLIC
3317 "-//OASIS//DTD Entity Resolution XML Catalog V1.0//EN"
3318 "http://www.oasis-open.org/committees/entity/release/1.0/catalog.dtd"&gt;
3319&lt;catalog xmlns="urn:oasis:names:tc:entity:xmlns:xml:catalog"&gt;
3320 &lt;public publicId="-//OASIS//DTD DocBook XML V4.1.2//EN"
3321 uri="http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd"/&gt;
3322...</pre>
3323
3324<p>This is the beginning of a catalog for DocBook 4.1.2, XML Catalogs are
3325written in XML, there is a specific namespace for catalog elements
3326"urn:oasis:names:tc:entity:xmlns:xml:catalog". The first entry in this
3327catalog is a <code>public</code> mapping it allows to associate a Public
3328Identifier with an URI.</p>
3329<pre>...
3330 &lt;rewriteSystem systemIdStartString="http://www.oasis-open.org/docbook/"
3331 rewritePrefix="file:///usr/share/xml/docbook/"/&gt;
3332...</pre>
3333
3334<p>A <code>rewriteSystem</code> is a very powerful instruction, it says that
3335any URI starting with a given prefix should be looked at another URI
3336constructed by replacing the prefix with an new one. In effect this acts like
3337a cache system for a full area of the Web. In practice it is extremely useful
3338with a file prefix if you have installed a copy of those resources on your
3339local system.</p>
3340<pre>...
3341&lt;delegatePublic publicIdStartString="-//OASIS//DTD XML Catalog //"
3342 catalog="file:///usr/share/xml/docbook.xml"/&gt;
3343&lt;delegatePublic publicIdStartString="-//OASIS//ENTITIES DocBook XML"
3344 catalog="file:///usr/share/xml/docbook.xml"/&gt;
3345&lt;delegatePublic publicIdStartString="-//OASIS//DTD DocBook XML"
3346 catalog="file:///usr/share/xml/docbook.xml"/&gt;
3347&lt;delegateSystem systemIdStartString="http://www.oasis-open.org/docbook/"
3348 catalog="file:///usr/share/xml/docbook.xml"/&gt;
3349&lt;delegateURI uriStartString="http://www.oasis-open.org/docbook/"
3350 catalog="file:///usr/share/xml/docbook.xml"/&gt;
3351...</pre>
3352
3353<p>Delegation is the core features which allows to build a tree of catalogs,
3354easier to maintain than a single catalog, based on Public Identifier, System
3355Identifier or URI prefixes it instructs the catalog software to look up
3356entries in another resource. This feature allow to build hierarchies of
3357catalogs, the set of entries presented should be sufficient to redirect the
3358resolution of all DocBook references to the specific catalog in
3359<code>/usr/share/xml/docbook.xml</code> this one in turn could delegate all
3360references for DocBook 4.2.1 to a specific catalog installed at the same time
3361as the DocBook resources on the local machine.</p>
3362
3363<h3><a name="reference">How to tune catalog usage:</a></h3>
3364
3365<p>The user can change the default catalog behaviour by redirecting queries
3366to its own set of catalogs, this can be done by setting the
3367<code>XML_CATALOG_FILES</code> environment variable to a list of catalogs, an
3368empty one should deactivate loading the default <code>/etc/xml/catalog</code>
3369default catalog</p>
3370
3371<h3><a name="validate">How to debug catalog processing:</a></h3>
3372
3373<p>Setting up the <code>XML_DEBUG_CATALOG</code> environment variable will
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]3374make libxml2 output debugging informations for each catalog operations, for
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]3375example:</p>
3376<pre>orchis:~/XML -&gt; xmllint --memory --noout test/ent2
3377warning: failed to load external entity "title.xml"
3378orchis:~/XML -&gt; export XML_DEBUG_CATALOG=
3379orchis:~/XML -&gt; xmllint --memory --noout test/ent2
3380Failed to parse catalog /etc/xml/catalog
3381Failed to parse catalog /etc/xml/catalog
3382warning: failed to load external entity "title.xml"
3383Catalogs cleanup
3384orchis:~/XML -&gt; </pre>
3385
3386<p>The test/ent2 references an entity, running the parser from memory makes
3387the base URI unavailable and the the "title.xml" entity cannot be loaded.
3388Setting up the debug environment variable allows to detect that an attempt is
3389made to load the <code>/etc/xml/catalog</code> but since it's not present the
3390resolution fails.</p>
3391
3392<p>But the most advanced way to debug XML catalog processing is to use the
3393<strong>xmlcatalog</strong> command shipped with libxml2, it allows to load
3394catalogs and make resolution queries to see what is going on. This is also
3395used for the regression tests:</p>
3396<pre>orchis:~/XML -&gt; ./xmlcatalog test/catalogs/docbook.xml \
3397 "-//OASIS//DTD DocBook XML V4.1.2//EN"
3398http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd
3399orchis:~/XML -&gt; </pre>
3400
3401<p>For debugging what is going on, adding one -v flags increase the verbosity
3402level to indicate the processing done (adding a second flag also indicate
3403what elements are recognized at parsing):</p>
3404<pre>orchis:~/XML -&gt; ./xmlcatalog -v test/catalogs/docbook.xml \
3405 "-//OASIS//DTD DocBook XML V4.1.2//EN"
3406Parsing catalog test/catalogs/docbook.xml's content
3407Found public match -//OASIS//DTD DocBook XML V4.1.2//EN
3408http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd
3409Catalogs cleanup
3410orchis:~/XML -&gt; </pre>
3411
3412<p>A shell interface is also available to debug and process multiple queries
3413(and for regression tests):</p>
3414<pre>orchis:~/XML -&gt; ./xmlcatalog -shell test/catalogs/docbook.xml \
3415 "-//OASIS//DTD DocBook XML V4.1.2//EN"
3416&gt; help
3417Commands available:
3418public PublicID: make a PUBLIC identifier lookup
3419system SystemID: make a SYSTEM identifier lookup
3420resolve PublicID SystemID: do a full resolver lookup
3421add 'type' 'orig' 'replace' : add an entry
3422del 'values' : remove values
3423dump: print the current catalog state
3424debug: increase the verbosity level
3425quiet: decrease the verbosity level
3426exit: quit the shell
3427&gt; public "-//OASIS//DTD DocBook XML V4.1.2//EN"
3428http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd
3429&gt; quit
3430orchis:~/XML -&gt; </pre>
3431
3432<p>This should be sufficient for most debugging purpose, this was actually
3433used heavily to debug the XML Catalog implementation itself.</p>
3434
3435<h3><a name="Declaring">How to create and maintain</a> catalogs:</h3>
3436
3437<p>Basically XML Catalogs are XML files, you can either use XML tools to
3438manage them or use <strong>xmlcatalog</strong> for this. The basic step is
3439to create a catalog the -create option provide this facility:</p>
3440<pre>orchis:~/XML -&gt; ./xmlcatalog --create tst.xml
3441&lt;?xml version="1.0"?&gt;
3442&lt;!DOCTYPE catalog PUBLIC "-//OASIS//DTD Entity Resolution XML Catalog V1.0//EN"
3443 "http://www.oasis-open.org/committees/entity/release/1.0/catalog.dtd"&gt;
3444&lt;catalog xmlns="urn:oasis:names:tc:entity:xmlns:xml:catalog"/&gt;
3445orchis:~/XML -&gt; </pre>
3446
3447<p>By default xmlcatalog does not overwrite the original catalog and save the
3448result on the standard output, this can be overridden using the -noout
3449option. The <code>-add</code> command allows to add entries in the
3450catalog:</p>
3451<pre>orchis:~/XML -&gt; ./xmlcatalog --noout --create --add "public" \
3452 "-//OASIS//DTD DocBook XML V4.1.2//EN" \
3453 http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd tst.xml
3454orchis:~/XML -&gt; cat tst.xml
3455&lt;?xml version="1.0"?&gt;
3456&lt;!DOCTYPE catalog PUBLIC "-//OASIS//DTD Entity Resolution XML Catalog V1.0//EN" \
3457 "http://www.oasis-open.org/committees/entity/release/1.0/catalog.dtd"&gt;
3458&lt;catalog xmlns="urn:oasis:names:tc:entity:xmlns:xml:catalog"&gt;
3459&lt;public publicId="-//OASIS//DTD DocBook XML V4.1.2//EN"
3460 uri="http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd"/&gt;
3461&lt;/catalog&gt;
3462orchis:~/XML -&gt; </pre>
3463
3464<p>The <code>-add</code> option will always take 3 parameters even if some of
3465the XML Catalog constructs (like nextCatalog) will have only a single
3466argument, just pass a third empty string, it will be ignored.</p>
3467
3468<p>Similarly the <code>-del</code> option remove matching entries from the
3469catalog:</p>
3470<pre>orchis:~/XML -&gt; ./xmlcatalog --del \
3471 "http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd" tst.xml
3472&lt;?xml version="1.0"?&gt;
3473&lt;!DOCTYPE catalog PUBLIC "-//OASIS//DTD Entity Resolution XML Catalog V1.0//EN"
3474 "http://www.oasis-open.org/committees/entity/release/1.0/catalog.dtd"&gt;
3475&lt;catalog xmlns="urn:oasis:names:tc:entity:xmlns:xml:catalog"/&gt;
3476orchis:~/XML -&gt; </pre>
3477
3478<p>The catalog is now empty. Note that the matching of <code>-del</code> is
3479exact and would have worked in a similar fashion with the Public ID
3480string.</p>
3481
3482<p>This is rudimentary but should be sufficient to manage a not too complex
3483catalog tree of resources.</p>
3484
3485<h3><a name="implemento">The implementor corner quick review of the
3486API:</a></h3>
3487
3488<p>First, and like for every other module of libxml, there is an
3489automatically generated <a href="html/libxml-catalog.html">API page for
3490catalog support</a>.</p>
3491
3492<p>The header for the catalog interfaces should be included as:</p>
3493<pre>#include &lt;libxml/catalog.h&gt;</pre>
3494
3495<p>The API is voluntarily kept very simple. First it is not obvious that
3496applications really need access to it since it is the default behaviour of
Daniel Veillard560c2a42003-07-06 21:13:49 +0000[diff] [blame]3497libxml2 (Note: it is possible to completely override libxml2 default catalog
3498by using <a href="html/libxml-parser.html">xmlSetExternalEntityLoader</a> to
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]3499plug an application specific resolver).</p>
3500
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]3501<p>Basically libxml2 support 2 catalog lists:</p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]3502<ul>
3503 <li>the default one, global shared by all the application</li>
3504 <li>a per-document catalog, this one is built if the document uses the
3505 <code>oasis-xml-catalog</code> PIs to specify its own catalog list, it is
3506 associated to the parser context and destroyed when the parsing context
3507 is destroyed.</li>
3508</ul>
3509
3510<p>the document one will be used first if it exists.</p>
3511
3512<h4>Initialization routines:</h4>
3513
3514<p>xmlInitializeCatalog(), xmlLoadCatalog() and xmlLoadCatalogs() should be
3515used at startup to initialize the catalog, if the catalog should be
3516initialized with specific values xmlLoadCatalog() or xmlLoadCatalogs()
3517should be called before xmlInitializeCatalog() which would otherwise do a
3518default initialization first.</p>
3519
3520<p>The xmlCatalogAddLocal() call is used by the parser to grow the document
3521own catalog list if needed.</p>
3522
3523<h4>Preferences setup:</h4>
3524
3525<p>The XML Catalog spec requires the possibility to select default
3526preferences between public and system delegation,
3527xmlCatalogSetDefaultPrefer() allows this, xmlCatalogSetDefaults() and
3528xmlCatalogGetDefaults() allow to control if XML Catalogs resolution should
3529be forbidden, allowed for global catalog, for document catalog or both, the
3530default is to allow both.</p>
3531
3532<p>And of course xmlCatalogSetDebug() allows to generate debug messages
3533(through the xmlGenericError() mechanism).</p>
3534
3535<h4>Querying routines:</h4>
3536
3537<p>xmlCatalogResolve(), xmlCatalogResolveSystem(), xmlCatalogResolvePublic()
3538and xmlCatalogResolveURI() are relatively explicit if you read the XML
3539Catalog specification they correspond to section 7 algorithms, they should
3540also work if you have loaded an SGML catalog with a simplified semantic.</p>
3541
3542<p>xmlCatalogLocalResolve() and xmlCatalogLocalResolveURI() are the same but
3543operate on the document catalog list</p>
3544
3545<h4>Cleanup and Miscellaneous:</h4>
3546
3547<p>xmlCatalogCleanup() free-up the global catalog, xmlCatalogFreeLocal() is
3548the per-document equivalent.</p>
3549
3550<p>xmlCatalogAdd() and xmlCatalogRemove() are used to dynamically modify the
3551first catalog in the global list, and xmlCatalogDump() allows to dump a
3552catalog state, those routines are primarily designed for xmlcatalog, I'm not
3553sure that exposing more complex interfaces (like navigation ones) would be
3554really useful.</p>
3555
3556<p>The xmlParseCatalogFile() is a function used to load XML Catalog files,
3557it's similar as xmlParseFile() except it bypass all catalog lookups, it's
3558provided because this functionality may be useful for client tools.</p>
3559
3560<h4>threaded environments:</h4>
3561
3562<p>Since the catalog tree is built progressively, some care has been taken to
3563try to avoid troubles in multithreaded environments. The code is now thread
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]3564safe assuming that the libxml2 library has been compiled with threads
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]3565support.</p>
3566
3567<p></p>
3568
3569<h3><a name="Other">Other resources</a></h3>
3570
3571<p>The XML Catalog specification is relatively recent so there isn't much
3572literature to point at:</p>
3573<ul>
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]3574 <li>You can find a good rant from Norm Walsh about <a
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]3575 href="http://www.arbortext.com/Think_Tank/XML_Resources/Issue_Three/issue_three.html">the
3576 need for catalogs</a>, it provides a lot of context informations even if
Daniel Veillard93d3a472002-04-26 14:04:55 +0000[diff] [blame]3577 I don't agree with everything presented. Norm also wrote a more recent
3578 article <a
3579 href="http://wwws.sun.com/software/xml/developers/resolver/article/">XML
3580 entities and URI resolvers</a> describing them.</li>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]3581 <li>An <a href="http://home.ccil.org/~cowan/XML/XCatalog.html">old XML
3582 catalog proposal</a> from John Cowan</li>
3583 <li>The <a href="http://www.rddl.org/">Resource Directory Description
3584 Language</a> (RDDL) another catalog system but more oriented toward
3585 providing metadata for XML namespaces.</li>
3586 <li>the page from the OASIS Technical <a
3587 href="http://www.oasis-open.org/committees/entity/">Committee on Entity
3588 Resolution</a> who maintains XML Catalog, you will find pointers to the
3589 specification update, some background and pointers to others tools
3590 providing XML Catalog support</li>
Daniel Veillardabfca612004-01-07 23:38:02 +0000[diff] [blame]3591 <li>There is a <a href="buildDocBookCatalog">shell script</a> to generate
Daniel Veillard35e937a2002-01-19 22:21:54 +0000[diff] [blame]3592 XML Catalogs for DocBook 4.1.2 . If it can write to the /etc/xml/
3593 directory, it will set-up /etc/xml/catalog and /etc/xml/docbook based on
3594 the resources found on the system. Otherwise it will just create
3595 ~/xmlcatalog and ~/dbkxmlcatalog and doing:
Daniel Veillard8594de92003-04-25 10:08:44 +0000[diff] [blame]3596 <p><code>export XML_CATALOG_FILES=$HOME/xmlcatalog</code></p>
Daniel Veillard35e937a2002-01-19 22:21:54 +0000[diff] [blame]3597 <p>should allow to process DocBook documentations without requiring
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]3598 network accesses for the DTD or stylesheets</p>
Daniel Veillard35e937a2002-01-19 22:21:54 +0000[diff] [blame]3599 </li>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]3600 <li>I have uploaded <a href="ftp://xmlsoft.org/test/dbk412catalog.tar.gz">a
Daniel Veillard35e937a2002-01-19 22:21:54 +0000[diff] [blame]3601 small tarball</a> containing XML Catalogs for DocBook 4.1.2 which seems
3602 to work fine for me too</li>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]3603 <li>The <a href="http://www.xmlsoft.org/xmlcatalog_man.html">xmlcatalog
3604 manual page</a></li>
3605</ul>
3606
3607<p>If you have suggestions for corrections or additions, simply contact
3608me:</p>
3609
3610<h2><a name="library">The parser interfaces</a></h2>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3611
3612<p>This section is directly intended to help programmers getting bootstrapped
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]3613using the XML tollkit from the C language. It is not intended to be
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]3614extensive. I hope the automatically generated documents will provide the
3615completeness required, but as a separate set of documents. The interfaces of
Daniel Veillard560c2a42003-07-06 21:13:49 +0000[diff] [blame]3616the XML parser are by principle low level, Those interested in a higher level
3617API should <a href="#DOM">look at DOM</a>.</p>
Daniel Veillardccb09631998-10-27 06:21:04 +0000[diff] [blame]3618
Daniel Veillard9cb5ff42001-01-29 08:22:21 +0000[diff] [blame]3619<p>The <a href="html/libxml-parser.html">parser interfaces for XML</a> are
3620separated from the <a href="html/libxml-htmlparser.html">HTML parser
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]3621interfaces</a>. Let's have a look at how the XML parser can be called:</p>
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]3622
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]3623<h3><a name="Invoking">Invoking the parser : the pull method</a></h3>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3624
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]3625<p>Usually, the first thing to do is to read an XML input. The parser accepts
3626documents either from in-memory strings or from files. The functions are
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3627defined in "parser.h":</p>
Daniel Veillard10c6a8f1998-10-28 01:00:12 +0000[diff] [blame]3628<dl>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3629 <dt><code>xmlDocPtr xmlParseMemory(char *buffer, int size);</code></dt>
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]3630 <dd><p>Parse a null-terminated string containing the document.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3631 </dd>
Daniel Veillard10c6a8f1998-10-28 01:00:12 +0000[diff] [blame]3632</dl>
3633<dl>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3634 <dt><code>xmlDocPtr xmlParseFile(const char *filename);</code></dt>
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]3635 <dd><p>Parse an XML document contained in a (possibly compressed)
3636 file.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3637 </dd>
Daniel Veillard10c6a8f1998-10-28 01:00:12 +0000[diff] [blame]3638</dl>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3639
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]3640<p>The parser returns a pointer to the document structure (or NULL in case of
Daniel Veillard10c6a8f1998-10-28 01:00:12 +0000[diff] [blame]3641failure).</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3642
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]3643<h3 id="Invoking1">Invoking the parser: the push method</h3>
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]3644
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]3645<p>In order for the application to keep the control when the document is
Daniel Veillard560c2a42003-07-06 21:13:49 +0000[diff] [blame]3646being fetched (which is common for GUI based programs) libxml2 provides a
3647push interface, too, as of version 1.8.3. Here are the interface
3648functions:</p>
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]3649<pre>xmlParserCtxtPtr xmlCreatePushParserCtxt(xmlSAXHandlerPtr sax,
3650 void *user_data,
3651 const char *chunk,
3652 int size,
3653 const char *filename);
3654int xmlParseChunk (xmlParserCtxtPtr ctxt,
3655 const char *chunk,
3656 int size,
3657 int terminate);</pre>
3658
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]3659<p>and here is a simple example showing how to use the interface:</p>
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]3660<pre> FILE *f;
3661
3662 f = fopen(filename, "r");
3663 if (f != NULL) {
3664 int res, size = 1024;
3665 char chars[1024];
3666 xmlParserCtxtPtr ctxt;
3667
3668 res = fread(chars, 1, 4, f);
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]3669 if (res &gt; 0) {
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]3670 ctxt = xmlCreatePushParserCtxt(NULL, NULL,
3671 chars, res, filename);
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]3672 while ((res = fread(chars, 1, size, f)) &gt; 0) {
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]3673 xmlParseChunk(ctxt, chars, res, 0);
3674 }
3675 xmlParseChunk(ctxt, chars, 0, 1);
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]3676 doc = ctxt-&gt;myDoc;
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]3677 xmlFreeParserCtxt(ctxt);
3678 }
3679 }</pre>
3680
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]3681<p>The HTML parser embedded into libxml2 also has a push interface; the
Daniel Veillardec70e912001-02-26 20:10:45 +0000[diff] [blame]3682functions are just prefixed by "html" rather than "xml".</p>
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]3683
3684<h3 id="Invoking2">Invoking the parser: the SAX interface</h3>
3685
Daniel Veillardec70e912001-02-26 20:10:45 +0000[diff] [blame]3686<p>The tree-building interface makes the parser memory-hungry, first loading
3687the document in memory and then building the tree itself. Reading a document
3688without building the tree is possible using the SAX interfaces (see SAX.h and
3689<a href="http://www.daa.com.au/~james/gnome/xml-sax/xml-sax.html">James
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]3690Henstridge's documentation</a>). Note also that the push interface can be
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]3691limited to SAX: just use the two first arguments of
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]3692<code>xmlCreatePushParserCtxt()</code>.</p>
Daniel Veillardccb09631998-10-27 06:21:04 +0000[diff] [blame]3693
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]3694<h3><a name="Building">Building a tree from scratch</a></h3>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3695
3696<p>The other way to get an XML tree in memory is by building it. Basically
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]3697there is a set of functions dedicated to building new elements. (These are
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]3698also described in &lt;libxml/tree.h&gt;.) For example, here is a piece of
3699code that produces the XML document used in the previous examples:</p>
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]3700<pre> #include &lt;libxml/tree.h&gt;
Daniel Veillard361d8452000-04-03 19:48:13 +0000[diff] [blame]3701 xmlDocPtr doc;
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]3702 xmlNodePtr tree, subtree;
3703
3704 doc = xmlNewDoc("1.0");
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]3705 doc-&gt;children = xmlNewDocNode(doc, NULL, "EXAMPLE", NULL);
3706 xmlSetProp(doc-&gt;children, "prop1", "gnome is great");
3707 xmlSetProp(doc-&gt;children, "prop2", "&amp; linux too");
3708 tree = xmlNewChild(doc-&gt;children, NULL, "head", NULL);
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]3709 subtree = xmlNewChild(tree, NULL, "title", "Welcome to Gnome");
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]3710 tree = xmlNewChild(doc-&gt;children, NULL, "chapter", NULL);
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]3711 subtree = xmlNewChild(tree, NULL, "title", "The Linux adventure");
3712 subtree = xmlNewChild(tree, NULL, "p", "bla bla bla ...");
3713 subtree = xmlNewChild(tree, NULL, "image", NULL);
3714 xmlSetProp(subtree, "href", "linus.gif");</pre>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3715
3716<p>Not really rocket science ...</p>
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]3717
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]3718<h3><a name="Traversing">Traversing the tree</a></h3>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3719
Daniel Veillard9cb5ff42001-01-29 08:22:21 +0000[diff] [blame]3720<p>Basically by <a href="html/libxml-tree.html">including "tree.h"</a> your
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]3721code has access to the internal structure of all the elements of the tree.
3722The names should be somewhat simple like <strong>parent</strong>,
Daniel Veillard306be992000-07-03 12:38:45 +0000[diff] [blame]3723<strong>children</strong>, <strong>next</strong>, <strong>prev</strong>,
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]3724<strong>properties</strong>, etc... For example, still with the previous
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]3725example:</p>
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]3726<pre><code>doc-&gt;children-&gt;children-&gt;children</code></pre>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3727
3728<p>points to the title element,</p>
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]3729<pre>doc-&gt;children-&gt;children-&gt;next-&gt;children-&gt;children</pre>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3730
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]3731<p>points to the text node containing the chapter title "The Linux
3732adventure".</p>
Daniel Veillard10c6a8f1998-10-28 01:00:12 +0000[diff] [blame]3733
Daniel Veillardb24054a1999-12-18 15:32:46 +0000[diff] [blame]3734<p><strong>NOTE</strong>: XML allows <em>PI</em>s and <em>comments</em> to be
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]3735present before the document root, so <code>doc-&gt;children</code> may point
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]3736to an element which is not the document Root Element; a function
Daniel Veillard5cb5ab81999-12-21 15:35:29 +0000[diff] [blame]3737<code>xmlDocGetRootElement()</code> was added for this purpose.</p>
Daniel Veillardb24054a1999-12-18 15:32:46 +0000[diff] [blame]3738
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]3739<h3><a name="Modifying">Modifying the tree</a></h3>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3740
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]3741<p>Functions are provided for reading and writing the document content. Here
Daniel Veillard9cb5ff42001-01-29 08:22:21 +0000[diff] [blame]3742is an excerpt from the <a href="html/libxml-tree.html">tree API</a>:</p>
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]3743<dl>
Daniel Veillarddd6b3671999-09-23 22:19:22 +0000[diff] [blame]3744 <dt><code>xmlAttrPtr xmlSetProp(xmlNodePtr node, const xmlChar *name, const
3745 xmlChar *value);</code></dt>
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]3746 <dd><p>This sets (or changes) an attribute carried by an ELEMENT node.
3747 The value can be NULL.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3748 </dd>
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]3749</dl>
3750<dl>
Daniel Veillarddd6b3671999-09-23 22:19:22 +0000[diff] [blame]3751 <dt><code>const xmlChar *xmlGetProp(xmlNodePtr node, const xmlChar
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3752 *name);</code></dt>
Daniel Veillardc92c3042000-09-29 02:42:04 +0000[diff] [blame]3753 <dd><p>This function returns a pointer to new copy of the property
3754 content. Note that the user must deallocate the result.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3755 </dd>
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]3756</dl>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3757
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]3758<p>Two functions are provided for reading and writing the text associated
3759with elements:</p>
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]3760<dl>
Daniel Veillarddd6b3671999-09-23 22:19:22 +0000[diff] [blame]3761 <dt><code>xmlNodePtr xmlStringGetNodeList(xmlDocPtr doc, const xmlChar
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3762 *value);</code></dt>
Daniel Veillardec70e912001-02-26 20:10:45 +0000[diff] [blame]3763 <dd><p>This function takes an "external" string and converts it to one
3764 text node or possibly to a list of entity and text nodes. All
3765 non-predefined entity references like &amp;Gnome; will be stored
3766 internally as entity nodes, hence the result of the function may not be
3767 a single node.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3768 </dd>
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]3769</dl>
3770<dl>
Daniel Veillarddd6b3671999-09-23 22:19:22 +0000[diff] [blame]3771 <dt><code>xmlChar *xmlNodeListGetString(xmlDocPtr doc, xmlNodePtr list, int
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3772 inLine);</code></dt>
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]3773 <dd><p>This function is the inverse of
3774 <code>xmlStringGetNodeList()</code>. It generates a new string
3775 containing the content of the text and entity nodes. Note the extra
3776 argument inLine. If this argument is set to 1, the function will expand
3777 entity references. For example, instead of returning the &amp;Gnome;
3778 XML encoding in the string, it will substitute it with its value (say,
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]3779 "GNU Network Object Model Environment").</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3780 </dd>
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]3781</dl>
Daniel Veillard10c6a8f1998-10-28 01:00:12 +0000[diff] [blame]3782
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]3783<h3><a name="Saving">Saving a tree</a></h3>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3784
3785<p>Basically 3 options are possible:</p>
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]3786<dl>
Daniel Veillarddd6b3671999-09-23 22:19:22 +0000[diff] [blame]3787 <dt><code>void xmlDocDumpMemory(xmlDocPtr cur, xmlChar**mem, int
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3788 *size);</code></dt>
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]3789 <dd><p>Returns a buffer into which the document has been saved.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3790 </dd>
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]3791</dl>
3792<dl>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3793 <dt><code>extern void xmlDocDump(FILE *f, xmlDocPtr doc);</code></dt>
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]3794 <dd><p>Dumps a document to an open file descriptor.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3795 </dd>
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]3796</dl>
3797<dl>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3798 <dt><code>int xmlSaveFile(const char *filename, xmlDocPtr cur);</code></dt>
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]3799 <dd><p>Saves the document to a file. In this case, the compression
3800 interface is triggered if it has been turned on.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3801 </dd>
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]3802</dl>
Daniel Veillard10c6a8f1998-10-28 01:00:12 +0000[diff] [blame]3803
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]3804<h3><a name="Compressio">Compression</a></h3>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3805
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]3806<p>The library transparently handles compression when doing file-based
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]3807accesses. The level of compression on saves can be turned on either globally
3808or individually for one file:</p>
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]3809<dl>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3810 <dt><code>int xmlGetDocCompressMode (xmlDocPtr doc);</code></dt>
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]3811 <dd><p>Gets the document compression ratio (0-9).</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3812 </dd>
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]3813</dl>
3814<dl>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3815 <dt><code>void xmlSetDocCompressMode (xmlDocPtr doc, int mode);</code></dt>
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]3816 <dd><p>Sets the document compression ratio.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3817 </dd>
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]3818</dl>
3819<dl>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3820 <dt><code>int xmlGetCompressMode(void);</code></dt>
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]3821 <dd><p>Gets the default compression ratio.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3822 </dd>
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]3823</dl>
3824<dl>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3825 <dt><code>void xmlSetCompressMode(int mode);</code></dt>
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]3826 <dd><p>Sets the default compression ratio.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3827 </dd>
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]3828</dl>
3829
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]3830<h2><a name="Entities">Entities or no entities</a></h2>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]3831
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]3832<p>Entities in principle are similar to simple C macros. An entity defines an
3833abbreviation for a given string that you can reuse many times throughout the
3834content of your document. Entities are especially useful when a given string
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]3835may occur frequently within a document, or to confine the change needed to a
3836document to a restricted area in the internal subset of the document (at the
3837beginning). Example:</p>
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]3838<pre>1 &lt;?xml version="1.0"?&gt;
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]38392 &lt;!DOCTYPE EXAMPLE SYSTEM "example.dtd" [
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]38403 &lt;!ENTITY xml "Extensible Markup Language"&gt;
38414 ]&gt;
38425 &lt;EXAMPLE&gt;
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]38436 &amp;xml;
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]38447 &lt;/EXAMPLE&gt;</pre>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]3845
3846<p>Line 3 declares the xml entity. Line 6 uses the xml entity, by prefixing
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]3847its name with '&amp;' and following it by ';' without any spaces added. There
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]3848are 5 predefined entities in libxml2 allowing you to escape characters with
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]3849predefined meaning in some parts of the xml document content:
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]3850<strong>&amp;lt;</strong> for the character '&lt;', <strong>&amp;gt;</strong>
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]3851for the character '&gt;', <strong>&amp;apos;</strong> for the character ''',
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]3852<strong>&amp;quot;</strong> for the character '"', and
3853<strong>&amp;amp;</strong> for the character '&amp;'.</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]3854
3855<p>One of the problems related to entities is that you may want the parser to
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]3856substitute an entity's content so that you can see the replacement text in
3857your application. Or you may prefer to keep entity references as such in the
3858content to be able to save the document back without losing this usually
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]3859precious information (if the user went through the pain of explicitly
3860defining entities, he may have a a rather negative attitude if you blindly
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]3861substitute them as saving time). The <a
Daniel Veillard5373ea12003-07-24 13:09:13 +0000[diff] [blame]3862href="html/libxml-parser.html#xmlSubstituteEntitiesDefault">xmlSubstituteEntitiesDefault()</a>
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]3863function allows you to check and change the behaviour, which is to not
3864substitute entities by default.</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]3865
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]3866<p>Here is the DOM tree built by libxml2 for the previous document in the
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]3867default case:</p>
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]3868<pre>/gnome/src/gnome-xml -&gt; ./xmllint --debug test/ent1
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]3869DOCUMENT
3870version=1.0
3871 ELEMENT EXAMPLE
3872 TEXT
3873 content=
3874 ENTITY_REF
3875 INTERNAL_GENERAL_ENTITY xml
3876 content=Extensible Markup Language
3877 TEXT
3878 content=</pre>
3879
3880<p>And here is the result when substituting entities:</p>
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]3881<pre>/gnome/src/gnome-xml -&gt; ./tester --debug --noent test/ent1
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]3882DOCUMENT
3883version=1.0
3884 ELEMENT EXAMPLE
3885 TEXT
3886 content= Extensible Markup Language</pre>
3887
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]3888<p>So, entities or no entities? Basically, it depends on your use case. I
3889suggest that you keep the non-substituting default behaviour and avoid using
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]3890entities in your XML document or data if you are not willing to handle the
3891entity references elements in the DOM tree.</p>
3892
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]3893<p>Note that at save time libxml2 enforces the conversion of the predefined
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]3894entities where necessary to prevent well-formedness problems, and will also
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]3895transparently replace those with chars (i.e. it will not generate entity
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]3896reference elements in the DOM tree or call the reference() SAX callback when
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]3897finding them in the input).</p>
3898
Daniel Veillard7b9c4b72000-08-25 16:26:50 +0000[diff] [blame]3899<p><span style="background-color: #FF0000">WARNING</span>: handling entities
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]3900on top of the libxml2 SAX interface is difficult!!! If you plan to use
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]3901non-predefined entities in your documents, then the learning curve to handle
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]3902then using the SAX API may be long. If you plan to use complex documents, I
Daniel Veillard7b9c4b72000-08-25 16:26:50 +0000[diff] [blame]3903strongly suggest you consider using the DOM interface instead and let libxml
Daniel Veillard8c6d6af2000-08-25 17:14:13 +0000[diff] [blame]3904deal with the complexity rather than trying to do it yourself.</p>
Daniel Veillard7b9c4b72000-08-25 16:26:50 +0000[diff] [blame]3905
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]3906<h2><a name="Namespaces">Namespaces</a></h2>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]3907
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]3908<p>The libxml2 library implements <a
Daniel Veillardec303412000-03-24 13:41:54 +0000[diff] [blame]3909href="http://www.w3.org/TR/REC-xml-names/">XML namespaces</a> support by
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]3910recognizing namespace constructs in the input, and does namespace lookup
Daniel Veillardec303412000-03-24 13:41:54 +0000[diff] [blame]3911automatically when building the DOM tree. A namespace declaration is
3912associated with an in-memory structure and all elements or attributes within
3913that namespace point to it. Hence testing the namespace is a simple and fast
3914equality operation at the user level.</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]3915
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]3916<p>I suggest that people using libxml2 use a namespace, and declare it in the
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]3917root element of their document as the default namespace. Then they don't need
3918to use the prefix in the content but we will have a basis for future semantic
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]3919refinement and merging of data from different sources. This doesn't increase
Daniel Veillardec70e912001-02-26 20:10:45 +0000[diff] [blame]3920the size of the XML output significantly, but significantly increases its
3921value in the long-term. Example:</p>
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]3922<pre>&lt;mydoc xmlns="http://mydoc.example.org/schemas/"&gt;
3923 &lt;elem1&gt;...&lt;/elem1&gt;
3924 &lt;elem2&gt;...&lt;/elem2&gt;
3925&lt;/mydoc&gt;</pre>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]3926
Daniel Veillardec70e912001-02-26 20:10:45 +0000[diff] [blame]3927<p>The namespace value has to be an absolute URL, but the URL doesn't have to
3928point to any existing resource on the Web. It will bind all the element and
Daniel Veillardc0801af2002-05-28 16:28:42 +0000[diff] [blame]3929attributes with that URL. I suggest to use an URL within a domain you
3930control, and that the URL should contain some kind of version information if
3931possible. For example, <code>"http://www.gnome.org/gnumeric/1.0/"</code> is a
3932good namespace scheme.</p>
Daniel Veillardec303412000-03-24 13:41:54 +0000[diff] [blame]3933
3934<p>Then when you load a file, make sure that a namespace carrying the
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]3935version-independent prefix is installed on the root element of your document,
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]3936and if the version information don't match something you know, warn the user
3937and be liberal in what you accept as the input. Also do *not* try to base
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]3938namespace checking on the prefix value. &lt;foo:text&gt; may be exactly the
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]3939same as &lt;bar:text&gt; in another document. What really matters is the URI
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]3940associated with the element or the attribute, not the prefix string (which is
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]3941just a shortcut for the full URI). In libxml, element and attributes have an
Daniel Veillardec303412000-03-24 13:41:54 +0000[diff] [blame]3942<code>ns</code> field pointing to an xmlNs structure detailing the namespace
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]3943prefix and its URI.</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]3944
3945<p>@@Interfaces@@</p>
Daniel Veillard3e35f8e2003-10-21 00:05:38 +0000[diff] [blame]3946<pre>xmlNodePtr node;
Daniel Veillardfc8dc352003-10-18 09:07:46 +0000[diff] [blame]3947if(!strncmp(node-&gt;name,"mytag",5)
3948 &amp;&amp; node-&gt;ns
3949 &amp;&amp; !strcmp(node-&gt;ns-&gt;href,"http://www.mysite.com/myns/1.0")) {
3950 ...
Daniel Veillard3e35f8e2003-10-21 00:05:38 +0000[diff] [blame]3951}</pre>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]3952
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]3953<p>Usually people object to using namespaces together with validity checking.
3954I will try to make sure that using namespaces won't break validity checking,
3955so even if you plan to use or currently are using validation I strongly
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]3956suggest adding namespaces to your document. A default namespace scheme
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]3957<code>xmlns="http://...."</code> should not break validity even on less
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]3958flexible parsers. Using namespaces to mix and differentiate content coming
Daniel Veillard3e35f8e2003-10-21 00:05:38 +0000[diff] [blame]3959from multiple DTDs will certainly break current validation schemes. To check
3960such documents one needs to use schema-validation, which is supported in
3961libxml2 as well. See <a href="http://www.relaxng.org/">relagx-ng</a> and <a
3962href="http://www.w3c.org/XML/Schema">w3c-schema</a>.</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]3963
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]3964<h2><a name="Upgrading">Upgrading 1.x code</a></h2>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]3965
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]3966<p>Incompatible changes:</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]3967
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]3968<p>Version 2 of libxml2 is the first version introducing serious backward
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]3969incompatible changes. The main goals were:</p>
3970<ul>
3971 <li>a general cleanup. A number of mistakes inherited from the very early
3972 versions couldn't be changed due to compatibility constraints. Example
3973 the "childs" element in the nodes.</li>
3974 <li>Uniformization of the various nodes, at least for their header and link
3975 parts (doc, parent, children, prev, next), the goal is a simpler
3976 programming model and simplifying the task of the DOM implementors.</li>
3977 <li>better conformances to the XML specification, for example version 1.x
3978 had an heuristic to try to detect ignorable white spaces. As a result the
3979 SAX event generated were ignorableWhitespace() while the spec requires
3980 character() in that case. This also mean that a number of DOM node
3981 containing blank text may populate the DOM tree which were not present
3982 before.</li>
3983</ul>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]3984
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]3985<h3>How to fix libxml-1.x code:</h3>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]3986
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]3987<p>So client code of libxml designed to run with version 1.x may have to be
3988changed to compile against version 2.x of libxml. Here is a list of changes
3989that I have collected, they may not be sufficient, so in case you find other
Daniel Veillardfc8dc352003-10-18 09:07:46 +0000[diff] [blame]3990change which are required, <a href="mailto:Daniel.Veillard@w3.org">drop me a
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]3991mail</a>:</p>
3992<ol>
3993 <li>The package name have changed from libxml to libxml2, the library name
3994 is now -lxml2 . There is a new xml2-config script which should be used to
3995 select the right parameters libxml2</li>
3996 <li>Node <strong>childs</strong> field has been renamed
3997 <strong>children</strong> so s/childs/children/g should be applied
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]3998 (probability of having "childs" anywhere else is close to 0+</li>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]3999 <li>The document don't have anymore a <strong>root</strong> element it has
4000 been replaced by <strong>children</strong> and usually you will get a
4001 list of element here. For example a Dtd element for the internal subset
4002 and it's declaration may be found in that list, as well as processing
4003 instructions or comments found before or after the document root element.
4004 Use <strong>xmlDocGetRootElement(doc)</strong> to get the root element of
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]4005 a document. Alternatively if you are sure to not reference DTDs nor have
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]4006 PIs or comments before or after the root element
4007 s/-&gt;root/-&gt;children/g will probably do it.</li>
4008 <li>The white space issue, this one is more complex, unless special case of
4009 validating parsing, the line breaks and spaces usually used for indenting
4010 and formatting the document content becomes significant. So they are
4011 reported by SAX and if your using the DOM tree, corresponding nodes are
4012 generated. Too approach can be taken:
4013 <ol>
4014 <li>lazy one, use the compatibility call
4015 <strong>xmlKeepBlanksDefault(0)</strong> but be aware that you are
4016 relying on a special (and possibly broken) set of heuristics of
4017 libxml to detect ignorable blanks. Don't complain if it breaks or
4018 make your application not 100% clean w.r.t. to it's input.</li>
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]4019 <li>the Right Way: change you code to accept possibly insignificant
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]4020 blanks characters, or have your tree populated with weird blank text
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]4021 nodes. You can spot them using the commodity function
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]4022 <strong>xmlIsBlankNode(node)</strong> returning 1 for such blank
4023 nodes.</li>
4024 </ol>
4025 <p>Note also that with the new default the output functions don't add any
4026 extra indentation when saving a tree in order to be able to round trip
4027 (read and save) without inflating the document with extra formatting
4028 chars.</p>
4029 </li>
4030 <li>The include path has changed to $prefix/libxml/ and the includes
4031 themselves uses this new prefix in includes instructions... If you are
4032 using (as expected) the
4033 <pre>xml2-config --cflags</pre>
4034 <p>output to generate you compile commands this will probably work out of
4035 the box</p>
4036 </li>
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]4037 <li>xmlDetectCharEncoding takes an extra argument indicating the length in
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]4038 byte of the head of the document available for character detection.</li>
4039</ol>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]4040
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]4041<h3>Ensuring both libxml-1.x and libxml-2.x compatibility</h3>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]4042
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]4043<p>Two new version of libxml (1.8.11) and libxml2 (2.3.4) have been released
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]4044to allow smooth upgrade of existing libxml v1code while retaining
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]4045compatibility. They offers the following:</p>
4046<ol>
4047 <li>similar include naming, one should use
4048 <strong>#include&lt;libxml/...&gt;</strong> in both cases.</li>
4049 <li>similar identifiers defined via macros for the child and root fields:
4050 respectively <strong>xmlChildrenNode</strong> and
4051 <strong>xmlRootNode</strong></li>
4052 <li>a new macro <strong>LIBXML_TEST_VERSION</strong> which should be
4053 inserted once in the client code</li>
4054</ol>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]4055
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]4056<p>So the roadmap to upgrade your existing libxml applications is the
4057following:</p>
4058<ol>
4059 <li>install the libxml-1.8.8 (and libxml-devel-1.8.8) packages</li>
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]4060 <li>find all occurrences where the xmlDoc <strong>root</strong> field is
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]4061 used and change it to <strong>xmlRootNode</strong></li>
Daniel Veillardc0801af2002-05-28 16:28:42 +0000[diff] [blame]4062 <li>similarly find all occurrences where the xmlNode
4063 <strong>childs</strong> field is used and change it to
4064 <strong>xmlChildrenNode</strong></li>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]4065 <li>add a <strong>LIBXML_TEST_VERSION</strong> macro somewhere in your
4066 <strong>main()</strong> or in the library init entry point</li>
4067 <li>Recompile, check compatibility, it should still work</li>
Daniel Veillardc0801af2002-05-28 16:28:42 +0000[diff] [blame]4068 <li>Change your configure script to look first for xml2-config and fall
4069 back using xml-config . Use the --cflags and --libs output of the command
4070 as the Include and Linking parameters needed to use libxml.</li>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]4071 <li>install libxml2-2.3.x and libxml2-devel-2.3.x (libxml-1.8.y and
4072 libxml-devel-1.8.y can be kept simultaneously)</li>
4073 <li>remove your config.cache, relaunch your configuration mechanism, and
4074 recompile, if steps 2 and 3 were done right it should compile as-is</li>
4075 <li>Test that your application is still running correctly, if not this may
4076 be due to extra empty nodes due to formating spaces being kept in libxml2
4077 contrary to libxml1, in that case insert xmlKeepBlanksDefault(1) in your
4078 code before calling the parser (next to
4079 <strong>LIBXML_TEST_VERSION</strong> is a fine place).</li>
4080</ol>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]4081
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]4082<p>Following those steps should work. It worked for some of my own code.</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]4083
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]4084<p>Let me put some emphasis on the fact that there is far more changes from
4085libxml 1.x to 2.x than the ones you may have to patch for. The overall code
4086has been considerably cleaned up and the conformance to the XML specification
4087has been drastically improved too. Don't take those changes as an excuse to
4088not upgrade, it may cost a lot on the long term ...</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]4089
Daniel Veillard52dcab32001-10-30 12:51:17 +0000[diff] [blame]4090<h2><a name="Thread">Thread safety</a></h2>
4091
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]4092<p>Starting with 2.4.7, libxml2 makes provisions to ensure that concurrent
Daniel Veillard52dcab32001-10-30 12:51:17 +0000[diff] [blame]4093threads can safely work in parallel parsing different documents. There is
4094however a couple of things to do to ensure it:</p>
4095<ul>
4096 <li>configure the library accordingly using the --with-threads options</li>
4097 <li>call xmlInitParser() in the "main" thread before using any of the
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]4098 libxml2 API (except possibly selecting a different memory allocator)</li>
Daniel Veillard52dcab32001-10-30 12:51:17 +0000[diff] [blame]4099</ul>
4100
4101<p>Note that the thread safety cannot be ensured for multiple threads sharing
4102the same document, the locking must be done at the application level, libxml
4103exports a basic mutex and reentrant mutexes API in &lt;libxml/threads.h&gt;.
4104The parts of the library checked for thread safety are:</p>
4105<ul>
4106 <li>concurrent loading</li>
4107 <li>file access resolution</li>
4108 <li>catalog access</li>
4109 <li>catalog building</li>
4110 <li>entities lookup/accesses</li>
4111 <li>validation</li>
4112 <li>global variables per-thread override</li>
4113 <li>memory handling</li>
4114</ul>
4115
4116<p>XPath is supposed to be thread safe now, but this wasn't tested
4117seriously.</p>
4118
Daniel Veillard35008381999-10-25 13:15:52 +0000[diff] [blame]4119<h2><a name="DOM"></a><a name="Principles">DOM Principles</a></h2>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]4120
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]4121<p><a href="http://www.w3.org/DOM/">DOM</a> stands for the <em>Document
4122Object Model</em>; this is an API for accessing XML or HTML structured
4123documents. Native support for DOM in Gnome is on the way (module gnome-dom),
4124and will be based on gnome-xml. This will be a far cleaner interface to
4125manipulate XML files within Gnome since it won't expose the internal
4126structure.</p>
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]4127
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]4128<p>The current DOM implementation on top of libxml2 is the <a
Daniel Veillarda47fb3d2001-03-25 17:23:49 +0000[diff] [blame]4129href="http://cvs.gnome.org/lxr/source/gdome2/">gdome2 Gnome module</a>, this
4130is a full DOM interface, thanks to Paolo Casarini, check the <a
4131href="http://www.cs.unibo.it/~casarini/gdome2/">Gdome2 homepage</a> for more
4132informations.</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]4133
Daniel Veillard35008381999-10-25 13:15:52 +0000[diff] [blame]4134<h2><a name="Example"></a><a name="real">A real example</a></h2>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]4135
4136<p>Here is a real size example, where the actual content of the application
4137data is not kept in the DOM tree but uses internal structures. It is based on
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]4138a proposal to keep a database of jobs related to Gnome, with an XML based
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]4139storage structure. Here is an <a href="gjobs.xml">XML encoded jobs
4140base</a>:</p>
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]4141<pre>&lt;?xml version="1.0"?&gt;
4142&lt;gjob:Helping xmlns:gjob="http://www.gnome.org/some-location"&gt;
4143 &lt;gjob:Jobs&gt;
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]4144
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]4145 &lt;gjob:Job&gt;
4146 &lt;gjob:Project ID="3"/&gt;
4147 &lt;gjob:Application&gt;GBackup&lt;/gjob:Application&gt;
4148 &lt;gjob:Category&gt;Development&lt;/gjob:Category&gt;
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]4149
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]4150 &lt;gjob:Update&gt;
4151 &lt;gjob:Status&gt;Open&lt;/gjob:Status&gt;
4152 &lt;gjob:Modified&gt;Mon, 07 Jun 1999 20:27:45 -0400 MET DST&lt;/gjob:Modified&gt;
4153 &lt;gjob:Salary&gt;USD 0.00&lt;/gjob:Salary&gt;
4154 &lt;/gjob:Update&gt;
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]4155
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]4156 &lt;gjob:Developers&gt;
4157 &lt;gjob:Developer&gt;
4158 &lt;/gjob:Developer&gt;
4159 &lt;/gjob:Developers&gt;
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]4160
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]4161 &lt;gjob:Contact&gt;
4162 &lt;gjob:Person&gt;Nathan Clemons&lt;/gjob:Person&gt;
4163 &lt;gjob:Email&gt;nathan@windsofstorm.net&lt;/gjob:Email&gt;
4164 &lt;gjob:Company&gt;
4165 &lt;/gjob:Company&gt;
4166 &lt;gjob:Organisation&gt;
4167 &lt;/gjob:Organisation&gt;
4168 &lt;gjob:Webpage&gt;
4169 &lt;/gjob:Webpage&gt;
4170 &lt;gjob:Snailmail&gt;
4171 &lt;/gjob:Snailmail&gt;
4172 &lt;gjob:Phone&gt;
4173 &lt;/gjob:Phone&gt;
4174 &lt;/gjob:Contact&gt;
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]4175
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]4176 &lt;gjob:Requirements&gt;
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]4177 The program should be released as free software, under the GPL.
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]4178 &lt;/gjob:Requirements&gt;
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]4179
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]4180 &lt;gjob:Skills&gt;
4181 &lt;/gjob:Skills&gt;
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]4182
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]4183 &lt;gjob:Details&gt;
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]4184 A GNOME based system that will allow a superuser to configure
4185 compressed and uncompressed files and/or file systems to be backed
4186 up with a supported media in the system. This should be able to
4187 perform via find commands generating a list of files that are passed
4188 to tar, dd, cpio, cp, gzip, etc., to be directed to the tape machine
4189 or via operations performed on the filesystem itself. Email
4190 notification and GUI status display very important.
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]4191 &lt;/gjob:Details&gt;
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]4192
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]4193 &lt;/gjob:Job&gt;
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]4194
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]4195 &lt;/gjob:Jobs&gt;
4196&lt;/gjob:Helping&gt;</pre>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]4197
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]4198<p>While loading the XML file into an internal DOM tree is a matter of
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]4199calling only a couple of functions, browsing the tree to gather the data and
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]4200generate the internal structures is harder, and more error prone.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]4201
4202<p>The suggested principle is to be tolerant with respect to the input
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]4203structure. For example, the ordering of the attributes is not significant,
4204the XML specification is clear about it. It's also usually a good idea not to
Daniel Veillardec70e912001-02-26 20:10:45 +0000[diff] [blame]4205depend on the order of the children of a given node, unless it really makes
4206things harder. Here is some code to parse the information for a person:</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]4207<pre>/*
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]4208 * A person record
4209 */
4210typedef struct person {
4211 char *name;
4212 char *email;
4213 char *company;
4214 char *organisation;
4215 char *smail;
4216 char *webPage;
4217 char *phone;
4218} person, *personPtr;
4219
4220/*
4221 * And the code needed to parse it
4222 */
4223personPtr parsePerson(xmlDocPtr doc, xmlNsPtr ns, xmlNodePtr cur) {
4224 personPtr ret = NULL;
4225
4226DEBUG("parsePerson\n");
4227 /*
4228 * allocate the struct
4229 */
4230 ret = (personPtr) malloc(sizeof(person));
4231 if (ret == NULL) {
4232 fprintf(stderr,"out of memory\n");
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]4233 return(NULL);
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]4234 }
4235 memset(ret, 0, sizeof(person));
4236
4237 /* We don't care what the top level element name is */
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]4238 cur = cur-&gt;xmlChildrenNode;
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]4239 while (cur != NULL) {
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]4240 if ((!strcmp(cur-&gt;name, "Person")) &amp;&amp; (cur-&gt;ns == ns))
4241 ret-&gt;name = xmlNodeListGetString(doc, cur-&gt;xmlChildrenNode, 1);
4242 if ((!strcmp(cur-&gt;name, "Email")) &amp;&amp; (cur-&gt;ns == ns))
4243 ret-&gt;email = xmlNodeListGetString(doc, cur-&gt;xmlChildrenNode, 1);
4244 cur = cur-&gt;next;
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]4245 }
4246
4247 return(ret);
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]4248}</pre>
4249
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]4250<p>Here are a couple of things to notice:</p>
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]4251<ul>
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]4252 <li>Usually a recursive parsing style is the more convenient one: XML data
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]4253 is by nature subject to repetitive constructs and usually exhibits highly
4254 structured patterns.</li>
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]4255 <li>The two arguments of type <em>xmlDocPtr</em> and <em>xmlNsPtr</em>,
4256 i.e. the pointer to the global XML document and the namespace reserved to
4257 the application. Document wide information are needed for example to
4258 decode entities and it's a good coding practice to define a namespace for
4259 your application set of data and test that the element and attributes
4260 you're analyzing actually pertains to your application space. This is
4261 done by a simple equality test (cur-&gt;ns == ns).</li>
Daniel Veillardec70e912001-02-26 20:10:45 +0000[diff] [blame]4262 <li>To retrieve text and attributes value, you can use the function
4263 <em>xmlNodeListGetString</em> to gather all the text and entity reference
4264 nodes generated by the DOM output and produce an single text string.</li>
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]4265</ul>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]4266
4267<p>Here is another piece of code used to parse another level of the
4268structure:</p>
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]4269<pre>#include &lt;libxml/tree.h&gt;
Daniel Veillard361d8452000-04-03 19:48:13 +0000[diff] [blame]4270/*
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]4271 * a Description for a Job
4272 */
4273typedef struct job {
4274 char *projectID;
4275 char *application;
4276 char *category;
4277 personPtr contact;
4278 int nbDevelopers;
4279 personPtr developers[100]; /* using dynamic alloc is left as an exercise */
4280} job, *jobPtr;
4281
4282/*
4283 * And the code needed to parse it
4284 */
4285jobPtr parseJob(xmlDocPtr doc, xmlNsPtr ns, xmlNodePtr cur) {
4286 jobPtr ret = NULL;
4287
4288DEBUG("parseJob\n");
4289 /*
4290 * allocate the struct
4291 */
4292 ret = (jobPtr) malloc(sizeof(job));
4293 if (ret == NULL) {
4294 fprintf(stderr,"out of memory\n");
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]4295 return(NULL);
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]4296 }
4297 memset(ret, 0, sizeof(job));
4298
4299 /* We don't care what the top level element name is */
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]4300 cur = cur-&gt;xmlChildrenNode;
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]4301 while (cur != NULL) {
4302
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]4303 if ((!strcmp(cur-&gt;name, "Project")) &amp;&amp; (cur-&gt;ns == ns)) {
4304 ret-&gt;projectID = xmlGetProp(cur, "ID");
4305 if (ret-&gt;projectID == NULL) {
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]4306 fprintf(stderr, "Project has no ID\n");
4307 }
4308 }
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]4309 if ((!strcmp(cur-&gt;name, "Application")) &amp;&amp; (cur-&gt;ns == ns))
4310 ret-&gt;application = xmlNodeListGetString(doc, cur-&gt;xmlChildrenNode, 1);
4311 if ((!strcmp(cur-&gt;name, "Category")) &amp;&amp; (cur-&gt;ns == ns))
4312 ret-&gt;category = xmlNodeListGetString(doc, cur-&gt;xmlChildrenNode, 1);
4313 if ((!strcmp(cur-&gt;name, "Contact")) &amp;&amp; (cur-&gt;ns == ns))
4314 ret-&gt;contact = parsePerson(doc, ns, cur);
4315 cur = cur-&gt;next;
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]4316 }
4317
4318 return(ret);
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]4319}</pre>
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]4320
Daniel Veillardec70e912001-02-26 20:10:45 +0000[diff] [blame]4321<p>Once you are used to it, writing this kind of code is quite simple, but
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]4322boring. Ultimately, it could be possible to write stubbers taking either C
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]4323data structure definitions, a set of XML examples or an XML DTD and produce
4324the code needed to import and export the content between C data and XML
4325storage. This is left as an exercise to the reader :-)</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]4326
Daniel Veillard6f0adb52000-07-03 11:41:26 +0000[diff] [blame]4327<p>Feel free to use <a href="example/gjobread.c">the code for the full C
4328parsing example</a> as a template, it is also available with Makefile in the
4329Gnome CVS base under gnome-xml/example</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]4330
Daniel Veillardc310d562000-06-23 18:32:15 +0000[diff] [blame]4331<h2><a name="Contributi">Contributions</a></h2>
4332<ul>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]4333 <li>Bjorn Reese, William Brack and Thomas Broyer have provided a number of
4334 patches, Gary Pennington worked on the validation API, threading support
4335 and Solaris port.</li>
4336 <li>John Fleck helps maintaining the documentation and man pages.</li>
Daniel Veillard7b4b2f92003-01-06 13:11:20 +0000[diff] [blame]4337 <li><a href="mailto:igor@zlatkovic.com">Igor Zlatkovic</a> is now the
4338 maintainer of the Windows port, <a
4339 href="http://www.zlatkovic.com/projects/libxml/index.html">he provides
4340 binaries</a></li>
Daniel Veillardaf43f632002-03-08 15:05:20 +0000[diff] [blame]4341 <li><a href="mailto:Gary.Pennington@sun.com">Gary Pennington</a> provides
4342 <a href="http://garypennington.net/libxml2/">Solaris binaries</a></li>
Daniel Veillarde356c282001-03-10 12:32:04 +0000[diff] [blame]4343 <li><a
4344 href="http://mail.gnome.org/archives/xml/2001-March/msg00014.html">Matt
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]4345 Sergeant</a> developed <a
4346 href="http://axkit.org/download/">XML::LibXSLT</a>, a Perl wrapper for
Daniel Veillardaf43f632002-03-08 15:05:20 +0000[diff] [blame]4347 libxml2/libxslt as part of the <a href="http://axkit.com/">AxKit XML
4348 application server</a></li>
4349 <li><a href="mailto:fnatter@gmx.net">Felix Natter</a> and <a
4350 href="mailto:geertk@ai.rug.nl">Geert Kloosterman</a> provide <a
Daniel Veillardca989762001-06-23 17:39:29 +0000[diff] [blame]4351 href="libxml-doc.el">an emacs module</a> to lookup libxml(2) functions
Daniel Veillard3f6f7f62000-06-30 17:58:25 +0000[diff] [blame]4352 documentation</li>
Daniel Veillardaf43f632002-03-08 15:05:20 +0000[diff] [blame]4353 <li><a href="mailto:sherwin@nlm.nih.gov">Ziying Sherwin</a> provided <a
4354 href="http://xmlsoft.org/messages/0488.html">man pages</a></li>
Daniel Veillard5168dbf2001-07-07 00:18:23 +0000[diff] [blame]4355 <li>there is a module for <a
4356 href="http://acs-misc.sourceforge.net/nsxml.html">libxml/libxslt support
4357 in OpenNSD/AOLServer</a></li>
Daniel Veillard2d347fa2002-03-17 10:34:11 +0000[diff] [blame]4358 <li><a href="mailto:dkuhlman@cutter.rexx.com">Dave Kuhlman</a> provided the
4359 first version of libxml/libxslt <a
4360 href="http://www.rexx.com/~dkuhlman">wrappers for Python</a></li>
Daniel Veillard1aadc442001-11-28 13:10:32 +0000[diff] [blame]4361 <li>Petr Kozelka provides <a
4362 href="http://sourceforge.net/projects/libxml2-pas">Pascal units to glue
4363 libxml2</a> with Kylix and Delphi and other Pascal compilers</li>
Daniel Veillard2d347fa2002-03-17 10:34:11 +0000[diff] [blame]4364 <li><a href="mailto:aleksey@aleksey.com">Aleksey Sanin</a> implemented the
4365 <a href="http://www.w3.org/Signature/">XML Canonicalization and XML
4366 Digital Signature</a> <a
4367 href="http://www.aleksey.com/xmlsec/">implementations for libxml2</a></li>
Daniel Veillard17bed982003-02-24 20:11:43 +0000[diff] [blame]4368 <li><a href="mailto:Steve.Ball@zveno.com">Steve Ball</a>, <a
4369 href="http://www.zveno.com/">Zveno</a> and contributors maintain <a
4370 href="http://tclxml.sourceforge.net/">tcl bindings for libxml2 and
4371 libxslt</a>, as well as <a
4372 href="http://tclxml.sf.net/tkxmllint.html">tkxmllint</a> a GUI for
4373 xmllint and <a href="http://tclxml.sf.net/tkxsltproc.html">tkxsltproc</a>
4374 a GUI for xsltproc.</li>
Daniel Veillardc310d562000-06-23 18:32:15 +0000[diff] [blame]4375</ul>
4376
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]4377<p></p>
Daniel Veillardccb09631998-10-27 06:21:04 +0000[diff] [blame]4378</body>
4379</html>