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blob: 5c3cc22e7dd3500ecfe59748b77d412b668de519 [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
21(but usable outside of the Gnome platform).
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]22XML itself is a metalanguage to design markup languages, i.e. text language
23where semantic and structure are added to the content using extra "markup"
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]24information enclosed between angle brackets. HTML is the most well-known
Daniel Veillard1eb24242002-03-18 11:33:03 +0000[diff] [blame]25markup language. Though the library is written in C <a href="python.html">a
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]26variety of language bindings</a> make it available in other environments.</p>
Daniel Veillard9c466822001-10-25 12:03:39 +0000[diff] [blame]27
Daniel Veillard710823b2003-03-04 10:05:52 +0000[diff] [blame]28<p>Libxml2 is known to be very portable, the library should build and work
29without serious troubles on a variety of systems (Linux, Unix, Windows,
30CygWin, MacOS, MacOS X, RISC Os, OS/2, VMS, QNX, MVS, ...)</p>
31
Daniel Veillard9c466822001-10-25 12:03:39 +0000[diff] [blame]32<p>Libxml2 implements a number of existing standards related to markup
33languages:</p>
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]34<ul>
Daniel Veillard9c466822001-10-25 12:03:39 +0000[diff] [blame]35 <li>the XML standard: <a
36 href="http://www.w3.org/TR/REC-xml">http://www.w3.org/TR/REC-xml</a></li>
37 <li>Namespaces in XML: <a
38 href="http://www.w3.org/TR/REC-xml-names/">http://www.w3.org/TR/REC-xml-names/</a></li>
39 <li>XML Base: <a
40 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]41 <li><a href="http://www.cis.ohio-state.edu/rfc/rfc2396.txt">RFC 2396</a> :
42 Uniform Resource Identifiers <a
Daniel Veillard9c466822001-10-25 12:03:39 +0000[diff] [blame]43 href="http://www.ietf.org/rfc/rfc2396.txt">http://www.ietf.org/rfc/rfc2396.txt</a></li>
44 <li>XML Path Language (XPath) 1.0: <a
45 href="http://www.w3.org/TR/xpath">http://www.w3.org/TR/xpath</a></li>
46 <li>HTML4 parser: <a
47 href="http://www.w3.org/TR/html401/">http://www.w3.org/TR/html401/</a></li>
48 <li>most of XML Pointer Language (XPointer) Version 1.0: <a
49 href="http://www.w3.org/TR/xptr">http://www.w3.org/TR/xptr</a></li>
50 <li>XML Inclusions (XInclude) Version 1.0: <a
51 href="http://www.w3.org/TR/xinclude/">http://www.w3.org/TR/xinclude/</a></li>
52 <li>[ISO-8859-1], <a
53 href="http://www.cis.ohio-state.edu/rfc/rfc2044.txt">rfc2044</a> [UTF-8]
54 and <a href="http://www.cis.ohio-state.edu/rfc/rfc2781.txt">rfc2781</a>
55 [UTF-16] core encodings</li>
56 <li>part of SGML Open Technical Resolution TR9401:1997</li>
57 <li>XML Catalogs Working Draft 06 August 2001: <a
58 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]59 <li>Canonical XML Version 1.0: <a
60 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]61 and the Exclusive XML Canonicalization CR draft <a
62 href="http://www.w3.org/TR/xml-exc-c14n">http://www.w3.org/TR/xml-exc-c14n</a></li>
Daniel Veillard17bed982003-02-24 20:11:43 +0000[diff] [blame]63 <li>Relax NG Committee Specification 3 December 2001 <a
64 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]65 <li>W3C XML Schemas Part 2: Datatypes <a
66 href="http://www.w3.org/TR/2001/REC-xmlschema-2-20010502/">REC 02 May
67 2001</a> except the base64Binary and hexBinary types</li>
Daniel Veillard96984452000-08-31 13:50:12 +0000[diff] [blame]68</ul>
69
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]70<p>In most cases libxml2 tries to implement the specifications in a relatively
Daniel Veillard42766c02002-08-22 20:52:17 +0000[diff] [blame]71strictly compliant way. As of release 2.4.16, libxml2 passes all 1800+ tests
72from the <a
Daniel Veillarda5393562002-02-20 11:40:49 +0000[diff] [blame]73href="http://www.oasis-open.org/committees/xml-conformance/">OASIS XML Tests
74Suite</a>.</p>
Daniel Veillard5b16f582002-02-20 11:38:46 +0000[diff] [blame]75
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]76<p>To some extent libxml2 provides support for the following additional
77specifications but doesn't claim to implement them completely:</p>
Daniel Veillard9c466822001-10-25 12:03:39 +0000[diff] [blame]78<ul>
79 <li>Document Object Model (DOM) <a
80 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]81 it doesn't implement the API itself, gdome2 does this on top of
Daniel Veillard9c466822001-10-25 12:03:39 +0000[diff] [blame]82 libxml2</li>
Daniel Veillardaf43f632002-03-08 15:05:20 +0000[diff] [blame]83 <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]84 libxml2 implements a basic FTP client code</li>
Daniel Veillardaf43f632002-03-08 15:05:20 +0000[diff] [blame]85 <li><a href="http://www.cis.ohio-state.edu/rfc/rfc1945.txt">RFC 1945</a> :
86 HTTP/1.0, again a basic HTTP client code</li>
Daniel Veillard9c466822001-10-25 12:03:39 +0000[diff] [blame]87 <li>SAX: a minimal SAX implementation compatible with early expat
88 versions</li>
89 <li>DocBook SGML v4: libxml2 includes a hackish parser to transition to
90 XML</li>
91</ul>
92
Daniel Veillardf83a2c72003-04-08 13:48:40 +0000[diff] [blame]93<p>A partial implementation of <a
94href="http://www.w3.org/TR/2001/REC-xmlschema-1-20010502/">XML Schemas Part
951: Structure</a> is being worked on but it would be far too early to make any
96conformance statement about it at the moment.</p>
Daniel Veillarde6d8e202002-05-02 06:11:10 +0000[diff] [blame]97
Daniel Veillard96984452000-08-31 13:50:12 +0000[diff] [blame]98<p>Separate documents:</p>
99<ul>
Daniel Veillardaf43f632002-03-08 15:05:20 +0000[diff] [blame]100 <li><a href="http://xmlsoft.org/XSLT/">the libxslt page</a> providing an
Daniel Veillard2d347fa2002-03-17 10:34:11 +0000[diff] [blame]101 implementation of XSLT 1.0 and common extensions like EXSLT for
102 libxml2</li>
Daniel Veillardc6271d22001-10-27 07:50:58 +0000[diff] [blame]103 <li><a href="http://www.cs.unibo.it/~casarini/gdome2/">the gdome2 page</a>
Daniel Veillard2d347fa2002-03-17 10:34:11 +0000[diff] [blame]104 : a standard DOM2 implementation for libxml2</li>
105 <li><a href="http://www.aleksey.com/xmlsec/">the XMLSec page</a>: an
106 implementation of <a href="http://www.w3.org/TR/xmldsig-core/">W3C XML
107 Digital Signature</a> for libxml2</li>
Daniel Veillarde6d8e202002-05-02 06:11:10 +0000[diff] [blame]108 <li>also check the related links section below for more related and active
109 projects.</li>
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]110</ul>
111
Daniel Veillard806cada2003-03-19 21:58:59 +0000[diff] [blame]112<p>Results of the <a
113href="http://xmlbench.sourceforge.net/results/benchmark/index.html">xmlbench
114benchmark</a> on sourceforge 19 March 2003 (smaller is better):</p>
Daniel Veillardd8da01c2003-03-24 15:58:23 +0000[diff] [blame]115
116<p align="center"><img src="benchmark.gif"
117alt="benchmark results for Expat Xerces libxml2 Oracle and Sun toolkits"></p>
Daniel Veillard806cada2003-03-19 21:58:59 +0000[diff] [blame]118
Daniel Veillarde1662542002-08-28 11:50:59 +0000[diff] [blame]119<p>Logo designed by <a href="mailto:liyanage@access.ch">Marc Liyanage</a>.</p>
120
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]121<h2><a name="Introducti">Introduction</a></h2>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]122
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]123<p>This document describes libxml, the <a
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]124href="http://www.w3.org/XML/">XML</a> C parser and toolkit developed for the <a
Daniel Veillardec78c0f2000-08-25 10:25:23 +0000[diff] [blame]125href="http://www.gnome.org/">Gnome</a> project. <a
126href="http://www.w3.org/XML/">XML is a standard</a> for building tag-based
127structured documents/data.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]128
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]129<p>Here are some key points about libxml:</p>
130<ul>
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]131 <li>Libxml2 exports Push (progressive) and Pull (blocking) type parser
Daniel Veillard2d347fa2002-03-17 10:34:11 +0000[diff] [blame]132 interfaces for both XML and HTML.</li>
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]133 <li>Libxml2 can do DTD validation at parse time, using a parsed document
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]134 instance, or with an arbitrary DTD.</li>
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]135 <li>Libxml2 includes complete <a
Daniel Veillard8c2ecaf2001-07-10 17:53:07 +0000[diff] [blame]136 href="http://www.w3.org/TR/xpath">XPath</a>, <a
137 href="http://www.w3.org/TR/xptr">XPointer</a> and <a
138 href="http://www.w3.org/TR/xinclude">XInclude</a> implementations.</li>
Daniel Veillardec78c0f2000-08-25 10:25:23 +0000[diff] [blame]139 <li>It is written in plain C, making as few assumptions as possible, and
Daniel Veillard189446d2000-10-13 10:23:06 +0000[diff] [blame]140 sticking closely to ANSI C/POSIX for easy embedding. Works on
Daniel Veillardab8500d2000-10-15 21:06:19 +0000[diff] [blame]141 Linux/Unix/Windows, ported to a number of other platforms.</li>
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]142 <li>Basic support for HTTP and FTP client allowing applications to fetch
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]143 remote resources.</li>
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]144 <li>The design is modular, most of the extensions can be compiled out.</li>
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]145 <li>The internal document representation is as close as possible to the <a
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]146 href="http://www.w3.org/DOM/">DOM</a> interfaces.</li>
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]147 <li>Libxml2 also has a <a href="http://www.megginson.com/SAX/index.html">SAX
Daniel Veillard402e8c82000-02-29 22:57:47 +0000[diff] [blame]148 like interface</a>; the interface is designed to be compatible with <a
149 href="http://www.jclark.com/xml/expat.html">Expat</a>.</li>
Daniel Veillardc575b992002-02-08 13:28:40 +0000[diff] [blame]150 <li>This library is released under the <a
151 href="http://www.opensource.org/licenses/mit-license.html">MIT
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]152 License</a>. See the Copyright file in the distribution for the precise
Daniel Veillardc575b992002-02-08 13:28:40 +0000[diff] [blame]153 wording.</li>
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]154</ul>
Daniel Veillardccb09631998-10-27 06:21:04 +0000[diff] [blame]155
Daniel Veillarde0c1d722001-03-21 10:28:36 +0000[diff] [blame]156<p>Warning: unless you are forced to because your application links with a
Daniel Veillard2d347fa2002-03-17 10:34:11 +0000[diff] [blame]157Gnome-1.X library requiring it, <strong><span
Daniel Veillarde0c1d722001-03-21 10:28:36 +0000[diff] [blame]158style="background-color: #FF0000">Do Not Use libxml1</span></strong>, use
159libxml2</p>
160
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]161<h2><a name="FAQ">FAQ</a></h2>
162
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]163<p>Table of Contents:</p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]164<ul>
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]165 <li><a href="FAQ.html#License">License(s)</a></li>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]166 <li><a href="FAQ.html#Installati">Installation</a></li>
167 <li><a href="FAQ.html#Compilatio">Compilation</a></li>
168 <li><a href="FAQ.html#Developer">Developer corner</a></li>
169</ul>
170
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]171<h3><a name="License">License</a>(s)</h3>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]172<ol>
173 <li><em>Licensing Terms for libxml</em>
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]174 <p>libxml2 is released under the <a
Daniel Veillardc575b992002-02-08 13:28:40 +0000[diff] [blame]175 href="http://www.opensource.org/licenses/mit-license.html">MIT
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]176 License</a>; see the file Copyright in the distribution for the precise
Daniel Veillardc575b992002-02-08 13:28:40 +0000[diff] [blame]177 wording</p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]178 </li>
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]179 <li><em>Can I embed libxml2 in a proprietary application ?</em>
Daniel Veillard42766c02002-08-22 20:52:17 +0000[diff] [blame]180 <p>Yes. The MIT License allows you to keep proprietary the changes you
181 made to libxml, but it would be graceful to send-back bug fixes and
182 improvements as patches for possible incorporation in the main
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]183 development tree.</p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]184 </li>
185</ol>
186
187<h3><a name="Installati">Installation</a></h3>
188<ol>
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]189 <li><strong><span style="background-color: #FF0000">Do
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]190 Not Use libxml1</span></strong>, use libxml2</li>
Daniel Veillardaf43f632002-03-08 15:05:20 +0000[diff] [blame]191 <li><em>Where can I get libxml</em> ?
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]192 <p>The original distribution comes from <a
193 href="ftp://rpmfind.net/pub/libxml/">rpmfind.net</a> or <a
Daniel Veillard6581e1b2003-02-09 22:21:43 +0000[diff] [blame]194 href="ftp://ftp.gnome.org/pub/GNOME/sources/libxml2/2.5/">gnome.org</a></p>
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]195 <p>Most Linux and BSD distributions include libxml, this is probably the
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]196 safer way for end-users to use libxml.</p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]197 <p>David Doolin provides precompiled Windows versions at <a
198 href="http://www.ce.berkeley.edu/~doolin/code/libxmlwin32/ ">http://www.ce.berkeley.edu/~doolin/code/libxmlwin32/</a></p>
199 </li>
200 <li><em>I see libxml and libxml2 releases, which one should I install ?</em>
201 <ul>
Daniel Veillard42766c02002-08-22 20:52:17 +0000[diff] [blame]202 <li>If you are not constrained by backward compatibility issues with
203 existing applications, install libxml2 only</li>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]204 <li>If you are not doing development, you can safely install both.
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]205 Usually the packages <a
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]206 href="http://rpmfind.net/linux/RPM/libxml.html">libxml</a> and <a
207 href="http://rpmfind.net/linux/RPM/libxml2.html">libxml2</a> are
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]208 compatible (this is not the case for development packages).</li>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]209 <li>If you are a developer and your system provides separate packaging
210 for shared libraries and the development components, it is possible
211 to install libxml and libxml2, and also <a
212 href="http://rpmfind.net/linux/RPM/libxml-devel.html">libxml-devel</a>
213 and <a
214 href="http://rpmfind.net/linux/RPM/libxml2-devel.html">libxml2-devel</a>
215 too for libxml2 &gt;= 2.3.0</li>
216 <li>If you are developing a new application, please develop against
217 libxml2(-devel)</li>
218 </ul>
219 </li>
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]220 <li><em>I can't install the libxml package, it conflicts with libxml0</em>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]221 <p>You probably have an old libxml0 package used to provide the shared
Daniel Veillard42766c02002-08-22 20:52:17 +0000[diff] [blame]222 library for libxml.so.0, you can probably safely remove it. The libxml
223 packages provided on <a
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]224 href="ftp://rpmfind.net/pub/libxml/">rpmfind.net</a> provide
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]225 libxml.so.0</p>
226 </li>
227 <li><em>I can't install the libxml(2) RPM package due to failed
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]228 dependencies</em>
229 <p>The most generic solution is to re-fetch the latest src.rpm , and
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]230 rebuild it locally with</p>
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]231 <p><code>rpm --rebuild libxml(2)-xxx.src.rpm</code>.</p>
Daniel Veillard42766c02002-08-22 20:52:17 +0000[diff] [blame]232 <p>If everything goes well it will generate two binary rpm packages (one
233 providing the shared libs and xmllint, and the other one, the -devel
234 package, providing includes, static libraries and scripts needed to build
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]235 applications with libxml(2)) that you can install locally.</p>
236 </li>
237</ol>
238
239<h3><a name="Compilatio">Compilation</a></h3>
240<ol>
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]241 <li><em>What is the process to compile libxml2 ?</em>
242 <p>As most UNIX libraries libxml2 follows the "standard":</p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]243 <p><code>gunzip -c xxx.tar.gz | tar xvf -</code></p>
244 <p><code>cd libxml-xxxx</code></p>
245 <p><code>./configure --help</code></p>
246 <p>to see the options, then the compilation/installation proper</p>
247 <p><code>./configure [possible options]</code></p>
248 <p><code>make</code></p>
249 <p><code>make install</code></p>
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]250 <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]251 update your list of installed shared libs.</p>
252 </li>
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]253 <li><em>What other libraries are needed to compile/install libxml2 ?</em>
254 <p>Libxml2 does not require any other library, the normal C ANSI API
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]255 should be sufficient (please report any violation to this rule you may
256 find).</p>
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]257 <p>However if found at configuration time libxml2 will detect and use the
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]258 following libs:</p>
259 <ul>
Daniel Veillardaf43f632002-03-08 15:05:20 +0000[diff] [blame]260 <li><a href="http://www.info-zip.org/pub/infozip/zlib/">libz</a> : a
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]261 highly portable and available widely compression library.</li>
262 <li>iconv: a powerful character encoding conversion library. It is
263 included by default in recent glibc libraries, so it doesn't need to
264 be installed specifically on Linux. It now seems a <a
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]265 href="http://www.opennc.org/onlinepubs/7908799/xsh/iconv.html">part
266 of the official UNIX</a> specification. Here is one <a
Daniel Veillarddad3f682002-11-17 16:47:27 +0000[diff] [blame]267 href="http://www.gnu.org/software/libiconv/">implementation of the
268 library</a> which source can be found <a
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]269 href="ftp://ftp.ilog.fr/pub/Users/haible/gnu/">here</a>.</li>
270 </ul>
271 </li>
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]272 <li><em>Make check fails on some platforms</em>
Daniel Veillard42766c02002-08-22 20:52:17 +0000[diff] [blame]273 <p>Sometimes the regression tests' results don't completely match the
274 value produced by the parser, and the makefile uses diff to print the
275 delta. On some platforms the diff return breaks the compilation process;
276 if the diff is small this is probably not a serious problem.</p>
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]277 <p>Sometimes (especially on Solaris) make checks fail due to limitations
Daniel Veillarde46182c2002-02-12 14:29:11 +0000[diff] [blame]278 in make. Try using GNU-make instead.</p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]279 </li>
280 <li><em>I use the CVS version and there is no configure script</em>
Daniel Veillard42766c02002-08-22 20:52:17 +0000[diff] [blame]281 <p>The configure script (and other Makefiles) are generated. Use the
282 autogen.sh script to regenerate the configure script and Makefiles,
283 like:</p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]284 <p><code>./autogen.sh --prefix=/usr --disable-shared</code></p>
285 </li>
286 <li><em>I have troubles when running make tests with gcc-3.0</em>
287 <p>It seems the initial release of gcc-3.0 has a problem with the
288 optimizer which miscompiles the URI module. Please use another
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]289 compiler.</p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]290 </li>
291</ol>
292
293<h3><a name="Developer">Developer</a> corner</h3>
294<ol>
Daniel Veillard93d95252003-04-29 20:25:40 +0000[diff] [blame]295 <li><em>Troubles compiling or linking programs using libxml2</em>
296 <p>Usually the problem comes from the fact that the compiler doesn't get
297 the right compilation or linking flags. There is a small shell script
298 <code>xml2-config</code> which is installed as part of libxml2 usual
299 install process which provides those flags. Use </p>
300 <p><code>xml2-config --cflags</code></p>
301 <p>to get the compilation flags and</p>
302 <p><code>xml2-config --libs</code></p>
303 <p>to get the linker flags. Usually this is done directly from the
304 Makefile as:</p>
305 <p><code>CFLAGS=`xml2-config --cflags`</code></p>
306 <p><code>LIBS=`xml2-config --libs`</code></p>
307 </li>
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]308 <li><em>xmlDocDump() generates output on one line.</em>
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]309 <p>Libxml2 will not <strong>invent</strong> spaces in the content of a
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]310 document since <strong>all spaces in the content of a document are
311 significant</strong>. If you build a tree from the API and want
312 indentation:</p>
313 <ol>
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]314 <li>the correct way is to generate those yourself too.</li>
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]315 <li>the dangerous way is to ask libxml2 to add those blanks to your
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]316 content <strong>modifying the content of your document in the
317 process</strong>. The result may not be what you expect. There is
318 <strong>NO</strong> way to guarantee that such a modification won't
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]319 affect other parts of the content of your document. See <a
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]320 href="http://xmlsoft.org/html/libxml-parser.html#XMLKEEPBLANKSDEFAULT">xmlKeepBlanksDefault
321 ()</a> and <a
322 href="http://xmlsoft.org/html/libxml-tree.html#XMLSAVEFORMATFILE">xmlSaveFormatFile
323 ()</a></li>
324 </ol>
325 </li>
326 <li>Extra nodes in the document:
327 <p><em>For a XML file as below:</em></p>
328 <pre>&lt;?xml version="1.0"?&gt;
329&lt;PLAN xmlns="http://www.argus.ca/autotest/1.0/"&gt;
330&lt;NODE CommFlag="0"/&gt;
331&lt;NODE CommFlag="1"/&gt;
332&lt;/PLAN&gt;</pre>
333 <p><em>after parsing it with the function
334 pxmlDoc=xmlParseFile(...);</em></p>
335 <p><em>I want to the get the content of the first node (node with the
336 CommFlag="0")</em></p>
337 <p><em>so I did it as following;</em></p>
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]338 <pre>xmlNodePtr pnode;
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]339pnode=pxmlDoc-&gt;children-&gt;children;</pre>
340 <p><em>but it does not work. If I change it to</em></p>
341 <pre>pnode=pxmlDoc-&gt;children-&gt;children-&gt;next;</pre>
342 <p><em>then it works. Can someone explain it to me.</em></p>
343 <p></p>
344 <p>In XML all characters in the content of the document are significant
345 <strong>including blanks and formatting line breaks</strong>.</p>
346 <p>The extra nodes you are wondering about are just that, text nodes with
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]347 the formatting spaces which are part of the document but that people tend
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]348 to forget. There is a function <a
349 href="http://xmlsoft.org/html/libxml-parser.html">xmlKeepBlanksDefault
350 ()</a> to remove those at parse time, but that's an heuristic, and its
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]351 use should be limited to cases where you are certain there is no
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]352 mixed-content in the document.</p>
353 </li>
354 <li><em>I get compilation errors of existing code like when accessing
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]355 <strong>root</strong> or <strong>child fields</strong> of nodes.</em>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]356 <p>You are compiling code developed for libxml version 1 and using a
357 libxml2 development environment. Either switch back to libxml v1 devel or
358 even better fix the code to compile with libxml2 (or both) by <a
359 href="upgrade.html">following the instructions</a>.</p>
360 </li>
361 <li><em>I get compilation errors about non existing
362 <strong>xmlRootNode</strong> or <strong>xmlChildrenNode</strong>
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]363 fields.</em>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]364 <p>The source code you are using has been <a
365 href="upgrade.html">upgraded</a> to be able to compile with both libxml
366 and libxml2, but you need to install a more recent version:
367 libxml(-devel) &gt;= 1.8.8 or libxml2(-devel) &gt;= 2.1.0</p>
368 </li>
369 <li><em>XPath implementation looks seriously broken</em>
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]370 <p>XPath implementation prior to 2.3.0 was really incomplete. Upgrade to
371 a recent version, there are no known bugs in the current version.</p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]372 </li>
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]373 <li><em>The example provided in the web page does not compile.</em>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]374 <p>It's hard to maintain the documentation in sync with the code
375 &lt;grin/&gt; ...</p>
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]376 <p>Check the previous points 1/ and 2/ raised before, and please send
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]377 patches.</p>
378 </li>
Daniel Veillard42766c02002-08-22 20:52:17 +0000[diff] [blame]379 <li><em>Where can I get more examples and information than privoded on the
380 web page?</em>
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]381 <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]382 can:</p>
383 <ul>
384 <li>check more deeply the <a href="html/libxml-lib.html">existing
385 generated doc</a></li>
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]386 <li>look for examples of use for libxml2 function using the Gnome code.
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]387 For example the following will query the full Gnome CVS base for the
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]388 use of the <strong>xmlAddChild()</strong> function:
389 <p><a
390 href="http://cvs.gnome.org/lxr/search?string=xmlAddChild">http://cvs.gnome.org/lxr/search?string=xmlAddChild</a></p>
391 <p>This may be slow, a large hardware donation to the gnome project
392 could cure this :-)</p>
393 </li>
394 <li><a
395 href="http://cvs.gnome.org/bonsai/rview.cgi?cvsroot=/cvs/gnome&amp;dir=gnome-xml">Browse
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]396 the libxml2 source</a> , I try to write code as clean and documented
Daniel Veillard42766c02002-08-22 20:52:17 +0000[diff] [blame]397 as possible, so looking at it may be helpful. In particular the code
398 of xmllint.c and of the various testXXX.c test programs should
399 provide good examples of how to do things with the library.</li>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]400 </ul>
401 </li>
402 <li>What about C++ ?
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]403 <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]404 of platforms, including embedded systems. I don't intend to convert to
405 C++.</p>
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]406 <p>There are however a few C++ wrappers which may fulfill your needs:</p>
Daniel Veillard9b6fd302002-05-13 12:06:47 +0000[diff] [blame]407 <ul>
408 <li>by Ari Johnson &lt;ari@btigate.com&gt;:
409 <p>Website: <a
410 href="http://lusis.org/~ari/xml++/">http://lusis.org/~ari/xml++/</a></p>
411 <p>Download: <a
412 href="http://lusis.org/~ari/xml++/libxml++.tar.gz">http://lusis.org/~ari/xml++/libxml++.tar.gz</a></p>
413 </li>
414 <li>by Peter Jones &lt;pjones@pmade.org&gt;
415 <p>Website: <a
416 href="http://pmade.org/pjones/software/xmlwrapp/">http://pmade.org/pjones/software/xmlwrapp/</a></p>
417 </li>
418 </ul>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]419 </li>
420 <li>How to validate a document a posteriori ?
421 <p>It is possible to validate documents which had not been validated at
Daniel Veillard42766c02002-08-22 20:52:17 +0000[diff] [blame]422 initial parsing time or documents which have been built from scratch
423 using the API. Use the <a
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]424 href="http://xmlsoft.org/html/libxml-valid.html#XMLVALIDATEDTD">xmlValidateDtd()</a>
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]425 function. It is also possible to simply add a DTD to an existing
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]426 document:</p>
427 <pre>xmlDocPtr doc; /* your existing document */
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]428xmlDtdPtr dtd = xmlParseDTD(NULL, filename_of_dtd); /* parse the DTD */
429
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]430 dtd-&gt;name = xmlStrDup((xmlChar*)"root_name"); /* use the given root */
431
432 doc-&gt;intSubset = dtd;
433 if (doc-&gt;children == NULL) xmlAddChild((xmlNodePtr)doc, (xmlNodePtr)dtd);
434 else xmlAddPrevSibling(doc-&gt;children, (xmlNodePtr)dtd);
435 </pre>
436 </li>
Daniel Veillarddad3f682002-11-17 16:47:27 +0000[diff] [blame]437 <li>So what is this funky "xmlChar" used all the time?
438 <p>It is a null terminated sequence of utf-8 characters. And only utf-8!
439 You need to convert strings encoded in different ways to utf-8 before
440 passing them to the API. This can be accomplished with the iconv library
441 for instance.</p>
John Fleck61f6fb62002-10-31 15:23:29 +0000[diff] [blame]442 </li>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]443 <li>etc ...</li>
444</ol>
445
446<p></p>
447
Daniel Veillard1177ca42003-04-26 22:29:54 +0000[diff] [blame]448<h2><a name="Documentat">Developer Documentation</a></h2>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]449
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]450<p>There are several on-line resources related to using libxml:</p>
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]451<ol>
Daniel Veillard321be0c2002-10-08 21:26:42 +0000[diff] [blame]452 <li>Use the <a href="search.php">search engine</a> to lookup
453 informations.</li>
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]454 <li>Check the <a href="FAQ.html">FAQ.</a></li>
Daniel Veillardc19fccc2000-07-03 11:52:01 +0000[diff] [blame]455 <li>Check the <a href="http://xmlsoft.org/html/libxml-lib.html">extensive
Daniel Veillard8c6d6af2000-08-25 17:14:13 +0000[diff] [blame]456 documentation</a> automatically extracted from code comments (using <a
457 href="http://cvs.gnome.org/bonsai/rview.cgi?cvsroot=/cvs/gnome&amp;dir=gtk-doc">gtk
458 doc</a>).</li>
Daniel Veillard8d869642000-07-14 12:12:59 +0000[diff] [blame]459 <li>Look at the documentation about <a href="encoding.html">libxml
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]460 internationalization support</a>.</li>
Daniel Veillardbc66f852002-01-14 09:49:20 +0000[diff] [blame]461 <li>This page provides a global overview and <a href="example.html">some
Daniel Veillard402e8c82000-02-29 22:57:47 +0000[diff] [blame]462 examples</a> on how to use libxml.</li>
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]463 <li>John Fleck's libxml2 tutorial: <a href="tutorial/index.html">html</a> or
Daniel Veillarddad3f682002-11-17 16:47:27 +0000[diff] [blame]464 <a href="tutorial/xmltutorial.pdf">pdf</a>.</li>
Daniel Veillard1177ca42003-04-26 22:29:54 +0000[diff] [blame]465 <li>If you need to parse large files, check the <a
466 href="xmlreader.html">xmlReader</a> API tutorial</li>
Daniel Veillardaf43f632002-03-08 15:05:20 +0000[diff] [blame]467 <li><a href="mailto:james@daa.com.au">James Henstridge</a> wrote <a
Daniel Veillard402e8c82000-02-29 22:57:47 +0000[diff] [blame]468 href="http://www.daa.com.au/~james/gnome/xml-sax/xml-sax.html">some nice
469 documentation</a> explaining how to use the libxml SAX interface.</li>
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]470 <li>George Lebl wrote <a
471 href="http://www-4.ibm.com/software/developer/library/gnome3/">an article
Daniel Veillard402e8c82000-02-29 22:57:47 +0000[diff] [blame]472 for IBM developerWorks</a> about using libxml.</li>
Daniel Veillardec303412000-03-24 13:41:54 +0000[diff] [blame]473 <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]474 file</a>.</li>
Daniel Veillard42766c02002-08-22 20:52:17 +0000[diff] [blame]475 <li>Read the <a href="upgrade.html">1.x to 2.x upgrade path</a>
476 description. If you are starting a new project using libxml you should
477 really use the 2.x version.</li>
Daniel Veillard845cce42002-01-09 11:51:37 +0000[diff] [blame]478 <li>And don't forget to look at the <a
479 href="http://mail.gnome.org/archives/xml/">mailing-list archive</a>.</li>
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]480</ol>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]481
Daniel Veillardd5f97f82000-09-17 16:38:14 +0000[diff] [blame]482<h2><a name="Reporting">Reporting bugs and getting help</a></h2>
Daniel Veillard4c3a2031999-11-19 17:46:26 +0000[diff] [blame]483
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]484<p>Well, bugs or missing features are always possible, and I will make a
485point of fixing them in a timely fashion. The best way to report a bug is to
486use the <a href="http://bugzilla.gnome.org/buglist.cgi?product=libxml">Gnome
Daniel Veillard42766c02002-08-22 20:52:17 +0000[diff] [blame]487bug tracking database</a> (make sure to use the "libxml2" module name). I
488look at reports there regularly and it's good to have a reminder when a bug
489is 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]490
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]491<p>There is also a mailing-list <a
Daniel Veillard3197f162001-04-04 00:40:08 +0000[diff] [blame]492href="mailto:xml@gnome.org">xml@gnome.org</a> for libxml, with an <a
493href="http://mail.gnome.org/archives/xml/">on-line archive</a> (<a
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]494href="http://xmlsoft.org/messages">old</a>). To subscribe to this list,
495please visit the <a
496href="http://mail.gnome.org/mailman/listinfo/xml">associated Web</a> page and
497follow the instructions. <strong>Do not send code, I won't debug it</strong>
498(but patches are really appreciated!).</p>
Daniel Veillard234547b2001-07-05 09:46:10 +0000[diff] [blame]499
Daniel Veillard008186f2001-09-13 14:24:44 +0000[diff] [blame]500<p>Check the following <strong><span style="color: #FF0000">before
501posting</span></strong>:</p>
Daniel Veillard234547b2001-07-05 09:46:10 +0000[diff] [blame]502<ul>
Daniel Veillard321be0c2002-10-08 21:26:42 +0000[diff] [blame]503 <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]504 search engine</a> to get information related to your problem.</li>
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]505 <li>Make sure you are <a href="ftp://xmlsoft.org/">using a recent
506 version</a>, and that the problem still shows up in a recent version.</li>
507 <li>Check the <a href="http://mail.gnome.org/archives/xml/">list
508 archives</a> to see if the problem was reported already. In this case
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]509 there is probably a fix available, similarly check the <a
Daniel Veillarde7ead2d2001-08-22 23:44:09 +0000[diff] [blame]510 href="http://bugzilla.gnome.org/buglist.cgi?product=libxml">registered
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]511 open bugs</a>.</li>
512 <li>Make sure you can reproduce the bug with xmllint or one of the test
513 programs found in source in the distribution.</li>
Daniel Veillard234547b2001-07-05 09:46:10 +0000[diff] [blame]514 <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]515 attachment)</li>
Daniel Veillard234547b2001-07-05 09:46:10 +0000[diff] [blame]516</ul>
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]517
Daniel Veillarda37aab82003-06-09 09:10:36 +0000[diff] [blame]518<p>Then send the bug with associated information to reproduce it to the <a
Daniel Veillard33a67802001-03-07 09:44:02 +0000[diff] [blame]519href="mailto:xml@gnome.org">xml@gnome.org</a> list; if it's really libxml
Daniel Veillard98d071d2003-01-10 09:22:44 +0000[diff] [blame]520related I will approve it. Please do not send mail to me directly, it makes
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]521things 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]522answer a given question, ask on the list.</p>
523
524<p>To <span style="color: #E50000">be really clear about support</span>:</p>
525<ul>
Daniel Veillarda37aab82003-06-09 09:10:36 +0000[diff] [blame]526 <li>Support or help <span style="color: #E50000">requests MUST be sent to
Daniel Veillard98d071d2003-01-10 09:22:44 +0000[diff] [blame]527 the list or on bugzilla</span> in case of problems, so that the Question
528 and Answers can be shared publicly. Failing to do so carries the implicit
529 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]530 others" and is not welcome. I will automatically Carbon-Copy the
531 xml@gnome.org mailing list for any technical reply made about libxml2 or
532 libxslt.</li>
Daniel Veillarda37aab82003-06-09 09:10:36 +0000[diff] [blame]533 <li>There is <span style="color: #E50000">no garantee of support</span>,
Daniel Veillard98d071d2003-01-10 09:22:44 +0000[diff] [blame]534 if your question remains unanswered after a week, repost it, making sure
Daniel Veillarda37aab82003-06-09 09:10:36 +0000[diff] [blame]535 you gave all the detail needed and the information requested.</li>
536 <li>Failing to provide information as requested or double checking first
Daniel Veillard98d071d2003-01-10 09:22:44 +0000[diff] [blame]537 for prior feedback also carries the implicit message "the time of the
538 library maintainers is less valuable than my time" and might not be
539 welcome.</li>
540</ul>
Daniel Veillard4c3a2031999-11-19 17:46:26 +0000[diff] [blame]541
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]542<p>Of course, bugs reported with a suggested patch for fixing them will
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]543probably be processed faster than those without.</p>
Daniel Veillardec303412000-03-24 13:41:54 +0000[diff] [blame]544
545<p>If you're looking for help, a quick look at <a
Daniel Veillardf7ed3362001-08-17 12:01:21 +0000[diff] [blame]546href="http://mail.gnome.org/archives/xml/">the list archive</a> may actually
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]547provide the answer. I usually send source samples when answering libxml2 usage
Daniel Veillard6f0adb52000-07-03 11:41:26 +0000[diff] [blame]548questions. The <a href="http://xmlsoft.org/html/book1.html">auto-generated
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]549documentation</a> is not as polished as I would like (i need to learn more
550about DocBook), but it's a good starting point.</p>
Daniel Veillardec303412000-03-24 13:41:54 +0000[diff] [blame]551
Daniel Veillardd5f97f82000-09-17 16:38:14 +0000[diff] [blame]552<h2><a name="help">How to help</a></h2>
553
554<p>You can help the project in various ways, the best thing to do first is to
555subscribe to the mailing-list as explained before, check the <a
Daniel Veillardf7ed3362001-08-17 12:01:21 +0000[diff] [blame]556href="http://mail.gnome.org/archives/xml/">archives </a>and the <a
557href="http://bugzilla.gnome.org/buglist.cgi?product=libxml">Gnome bug
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]558database</a>:</p>
Daniel Veillardd5f97f82000-09-17 16:38:14 +0000[diff] [blame]559<ol>
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]560 <li>Provide patches when you find problems.</li>
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]561 <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]562 be integrated in all cases but help pinpointing portability problems
563 and</li>
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]564 <li>Provide documentation fixes (either as patches to the code comments or
Daniel Veillardd5f97f82000-09-17 16:38:14 +0000[diff] [blame]565 as HTML diffs).</li>
Daniel Veillard42766c02002-08-22 20:52:17 +0000[diff] [blame]566 <li>Provide new documentations pieces (translations, examples, etc
567 ...).</li>
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]568 <li>Check the TODO file and try to close one of the items.</li>
569 <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]570 provide a fix. <a href="mailto:daniel@veillard.com">Get in touch with me
571 </a>before to avoid synchronization problems and check that the suggested
572 fix will fit in nicely :-)</li>
Daniel Veillardd5f97f82000-09-17 16:38:14 +0000[diff] [blame]573</ol>
574
Daniel Veillard10a2c651999-12-12 13:03:50 +0000[diff] [blame]575<h2><a name="Downloads">Downloads</a></h2>
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]576
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]577<p>The latest versions of libxml2 can be found on <a
Daniel Veillard20c8cf22001-06-26 22:47:36 +0000[diff] [blame]578href="ftp://xmlsoft.org/">xmlsoft.org</a> (<a
579href="ftp://speakeasy.rpmfind.net/pub/libxml/">Seattle</a>, <a
580href="ftp://fr.rpmfind.net/pub/libxml/">France</a>) or on the <a
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]581href="ftp://ftp.gnome.org/pub/GNOME/MIRRORS.html">Gnome FTP server</a> either
Daniel Veillard6581e1b2003-02-09 22:21:43 +0000[diff] [blame]582as a <a href="ftp://ftp.gnome.org/pub/GNOME/sources/libxml2/2.5/">source
MDT 2002 John Fleck30c70542002-09-24 14:24:54 +0000[diff] [blame]583archive</a><!-- commenting this out because they seem to have disappeared or <a
Daniel Veillarda41123c2001-04-22 19:31:20 +0000[diff] [blame]584href="ftp://ftp.gnome.org/pub/GNOME/stable/redhat/i386/libxml/">RPM
Daniel Veillarde16b5742002-09-26 17:50:03 +0000[diff] [blame]585packages</a> -->
Daniel Veillard321be0c2002-10-08 21:26:42 +0000[diff] [blame]586 , Antonin Sprinzl also provide <a href="ftp://gd.tuwien.ac.at/pub/libxml/">a
Daniel Veillarde16b5742002-09-26 17:50:03 +0000[diff] [blame]587mirror in Austria</a>. (NOTE that you need both the <a
Daniel Veillardc19fccc2000-07-03 11:52:01 +0000[diff] [blame]588href="http://rpmfind.net/linux/RPM/libxml2.html">libxml(2)</a> and <a
589href="http://rpmfind.net/linux/RPM/libxml2-devel.html">libxml(2)-devel</a>
Daniel Veillardb46a5732003-04-08 13:35:48 +0000[diff] [blame]590packages installed to compile applications using libxml.)</p>
591
592<p>Binary ports:</p>
593<ul>
594 <li>Red Hat RPMs for i386 are available directly on <a
595 href="ftp://xmlsoft.org/">xmlsoft.org</a>, the source RPM will compile on
596 any architecture supported by Red Hat.</li>
Daniel Veillardf83a2c72003-04-08 13:48:40 +0000[diff] [blame]597 <li><p><a href="mailto:igor@zlatkovic.com">Igor Zlatkovic</a></p>
Daniel Veillardce192eb2003-04-16 15:58:05 +0000[diff] [blame]598 is now the maintainer of the Windows port, <a
Daniel Veillardb46a5732003-04-08 13:35:48 +0000[diff] [blame]599 href="http://www.zlatkovic.com/projects/libxml/index.html">he provides
600 binaries</a>.</li>
601 <li><a href="mailto:Gary.Pennington@sun.com">Gary Pennington</a> provides
602 <a href="http://garypennington.net/libxml2/">Solaris binaries</a>.</li>
603 <li><a href="mailto:Steve.Ball@zveno.com">Steve Ball</a> provides <a
604 href="http://www.zveno.com/open_source/libxml2xslt.html">Mac Os X
605 binaries</a>.</li>
606 <li>The HP-UX porting center provides <a
607 href="http://hpux.connect.org.uk/hppd/hpux/Gnome/">HP-UX binaries</a></li>
608</ul>
609
610<p>If you know other supported binary ports, please <a
611href="http://veillard.com/">contact me</a>.</p>
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]612
Daniel Veillard6c8b1172000-03-01 00:40:41 +0000[diff] [blame]613<p><a name="Snapshot">Snapshot:</a></p>
614<ul>
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]615 <li>Code from the W3C cvs base gnome-xml <a
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]616 href="ftp://xmlsoft.org/cvs-snapshot.tar.gz">cvs-snapshot.tar.gz</a>.</li>
Daniel Veillard6c8b1172000-03-01 00:40:41 +0000[diff] [blame]617 <li>Docs, content of the web site, the list archive included <a
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]618 href="ftp://xmlsoft.org/libxml-docs.tar.gz">libxml-docs.tar.gz</a>.</li>
Daniel Veillard6c8b1172000-03-01 00:40:41 +0000[diff] [blame]619</ul>
620
Daniel Veillardc6271d22001-10-27 07:50:58 +0000[diff] [blame]621<p><a name="Contribs">Contributions:</a></p>
Daniel Veillard6c8b1172000-03-01 00:40:41 +0000[diff] [blame]622
623<p>I do accept external contributions, especially if compiling on another
Daniel Veillardc6271d22001-10-27 07:50:58 +0000[diff] [blame]624platform, get in touch with me to upload the package, wrappers for various
Daniel Veillard51095312001-10-28 18:51:57 +0000[diff] [blame]625languages have been provided, and can be found in the <a
626href="contribs.html">contrib section</a></p>
Daniel Veillard6c8b1172000-03-01 00:40:41 +0000[diff] [blame]627
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]628<p>Libxml2 is also available from CVS:</p>
Daniel Veillard10a2c651999-12-12 13:03:50 +0000[diff] [blame]629<ul>
Daniel Veillard10a2c651999-12-12 13:03:50 +0000[diff] [blame]630 <li><p>The <a
631 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]632 CVS base</a>. Check the <a
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]633 href="http://developer.gnome.org/tools/cvs.html">Gnome CVS Tools</a>
634 page; the CVS module is <b>gnome-xml</b>.</p>
Daniel Veillard10a2c651999-12-12 13:03:50 +0000[diff] [blame]635 </li>
Daniel Veillard82687162001-01-22 15:32:01 +0000[diff] [blame]636 <li>The <strong>libxslt</strong> module is also present there</li>
Daniel Veillard10a2c651999-12-12 13:03:50 +0000[diff] [blame]637</ul>
638
639<h2><a name="News">News</a></h2>
640
Daniel Veillard944b5ff1999-12-15 19:08:24 +0000[diff] [blame]641<h3>CVS only : check the <a
642href="http://cvs.gnome.org/lxr/source/gnome-xml/ChangeLog">Changelog</a> file
Daniel Veillard189446d2000-10-13 10:23:06 +0000[diff] [blame]643for a really accurate description</h3>
Daniel Veillardab8500d2000-10-15 21:06:19 +0000[diff] [blame]644
Daniel Veillarde6d8e202002-05-02 06:11:10 +0000[diff] [blame]645<p>Items not finished and worked on, get in touch with the list if you want
646to test those</p>
Daniel Veillardab8500d2000-10-15 21:06:19 +0000[diff] [blame]647<ul>
Daniel Veillard72fef162003-02-05 14:31:19 +0000[diff] [blame]648 <li>More testing on RelaxNG</li>
Daniel Veillardcf27f7c2002-04-30 07:12:39 +0000[diff] [blame]649 <li>Finishing up <a href="http://www.w3.org/TR/xmlschema-1/">XML
Daniel Veillard72fef162003-02-05 14:31:19 +0000[diff] [blame]650 Schemas</a></li>
651</ul>
652
Daniel Veillard92fc02c2003-04-24 23:12:35 +0000[diff] [blame]653<h3>2.5.7: Apr 25 2003</h3>
654<ul>
655 <li>Relax-NG: Compiling to regexp and streaming validation on top of the
656 xmlReader interface, added to xmllint --stream</li>
657 <li>xmlReader: Expand(), Next() and DOM access glue, bug fixes</li>
658 <li>Support for large files: RGN validated a 4.5GB instance</li>
659 <li>Thread support is now configured in by default</li>
660 <li>Fixes: update of the Trio code (Bjorn), WXS Date and Duration fixes
661 (Charles Bozeman), DTD and namespaces (Brent Hendricks), HTML push parser
662 and zero bytes handling, some missing Windows file path conversions,
663 behaviour of the parser and validator in the presence of "out of memory"
Daniel Veillard93d95252003-04-29 20:25:40 +0000[diff] [blame]664 error conditions</li>
Daniel Veillard92fc02c2003-04-24 23:12:35 +0000[diff] [blame]665 <li>extended the API to be able to plug a garbage collecting memory
666 allocator, added xmlMallocAtomic() and modified the allocations
667 accordingly.</li>
668 <li>Performances: removed excessive malloc() calls, speedup of the push and
669 xmlReader interfaces, removed excessive thread locking</li>
670 <li>Documentation: man page (John Fleck), xmlReader documentation</li>
671 <li>Python: adding binding for xmlCatalogAddLocal (Brent M Hendricks)</li>
672</ul>
673
Daniel Veillardc2d4a932003-04-01 11:13:05 +0000[diff] [blame]674<h3>2.5.6: Apr 1 2003</h3>
675<ul>
676 <li>Fixed W3C XML Schemas datatype, should be compliant now except for
677 binHex and base64 which are not supported yet.</li>
678 <li>bug fixes: non-ASCII IDs, HTML output, XInclude on large docs and
679 XInclude entities handling, encoding detection on external subsets, XML
680 Schemas bugs and memory leaks, HTML parser (James Bursa)</li>
681 <li>portability: python/trio (Albert Chin), Sun compiler warnings</li>
682 <li>documentation: added --relaxng option to xmllint man page (John)</li>
683 <li>improved error reporting: xml:space, start/end tag mismatches, Relax NG
684 errors</li>
685</ul>
686
687<h3>2.5.5: Mar 24 2003</h3>
Daniel Veillardd8da01c2003-03-24 15:58:23 +0000[diff] [blame]688<ul>
689 <li>Lot of fixes on the Relax NG implementation. More testing including
690 DocBook and TEI examples.</li>
691 <li>Increased the support for W3C XML Schemas datatype</li>
692 <li>Several bug fixes in the URI handling layer</li>
693 <li>Bug fixes: HTML parser, xmlReader, DTD validation, XPath, encoding
694 conversion, line counting in the parser.</li>
695 <li>Added support for $XMLLINT_INDENT environment variable, FTP delete</li>
696 <li>Fixed the RPM spec file name</li>
697</ul>
698
Daniel Veillard17bed982003-02-24 20:11:43 +0000[diff] [blame]699<h3>2.5.4: Feb 20 2003</h3>
700<ul>
701 <li>Conformance testing and lot of fixes on Relax NG and XInclude
702 implementation</li>
703 <li>Implementation of XPointer element() scheme</li>
704 <li>Bug fixes: XML parser, XInclude entities merge, validity checking on
705 namespaces,
706 <p>2 serialization bugs, node info generation problems, a DTD regexp
707 generation problem.</p>
708 </li>
709 <li>Portability: windows updates and path canonicalization (Igor)</li>
710 <li>A few typo fixes (Kjartan Maraas)</li>
711 <li>Python bindings generator fixes (Stephane Bidoul)</li>
712</ul>
713
Daniel Veillard1d788d22003-02-10 16:21:58 +0000[diff] [blame]714<h3>2.5.3: Feb 10 2003</h3>
715<ul>
716 <li>RelaxNG and XML Schemas datatypes improvements, and added a first
717 version of RelaxNG Python bindings</li>
718 <li>Fixes: XLink (Sean Chittenden), XInclude (Sean Chittenden), API fix for
719 serializing namespace nodes, encoding conversion bug, XHTML1
720 serialization</li>
721 <li>Portability fixes: Windows (Igor), AMD 64bits RPM spec file</li>
722</ul>
723
Daniel Veillard72fef162003-02-05 14:31:19 +0000[diff] [blame]724<h3>2.5.2: Feb 5 2003</h3>
725<ul>
726 <li>First implementation of RelaxNG, added --relaxng flag to xmllint</li>
727 <li>Schemas support now compiled in by default.</li>
728 <li>Bug fixes: DTD validation, namespace checking, XInclude and entities,
729 delegateURI in XML Catalogs, HTML parser, XML reader (Stéphane Bidoul),
730 XPath parser and evaluation, UTF8ToUTF8 serialization, XML reader memory
731 consumption, HTML parser, HTML serialization in the presence of
732 namespaces</li>
733 <li>added an HTML API to check elements and attributes.</li>
734 <li>Documentation improvement, PDF for the tutorial (John Fleck), doc
735 patches (Stefan Kost)</li>
736 <li>Portability fixes: NetBSD (Julio Merino), Windows (Igor Zlatkovic)</li>
737 <li>Added python bindings for XPointer, contextual error reporting
738 (Stéphane Bidoul)</li>
739 <li>URI/file escaping problems (Stefano Zacchiroli)</li>
Daniel Veillardcf27f7c2002-04-30 07:12:39 +0000[diff] [blame]740</ul>
741
Daniel Veillarde2830f12003-01-08 17:47:49 +0000[diff] [blame]742<h3>2.5.1: Jan 8 2003</h3>
743<ul>
744 <li>Fixes a memory leak and configuration/compilation problems in 2.5.0</li>
745 <li>documentation updates (John)</li>
746 <li>a couple of XmlTextReader fixes</li>
747</ul>
748
Daniel Veillard7b4b2f92003-01-06 13:11:20 +0000[diff] [blame]749<h3>2.5.0: Jan 6 2003</h3>
750<ul>
751 <li>New <a href="xmlreader.html">XmltextReader interface</a> based on C#
752 API (with help of Stéphane Bidoul)</li>
753 <li>Windows: more exports, including the new API (Igor)</li>
754 <li>XInclude fallback fix</li>
755 <li>Python: bindings for the new API, packaging (Stéphane Bidoul),
756 drv_libxml2.py Python xml.sax driver (Stéphane Bidoul), fixes, speedup
757 and iterators for Python-2.2 (Hannu Krosing)</li>
758 <li>Tutorial fixes (john Fleck and Niraj Tolia) xmllint man update
759 (John)</li>
760 <li>Fix an XML parser bug raised by Vyacheslav Pindyura</li>
761 <li>Fix for VMS serialization (Nigel Hall) and config (Craig A. Berry)</li>
762 <li>Entities handling fixes</li>
763 <li>new API to optionally track node creation and deletion (Lukas
764 Schroeder)</li>
765 <li>Added documentation for the XmltextReader interface and some <a
766 href="guidelines.html">XML guidelines</a></li>
767</ul>
768
Daniel Veillardc1eed322002-12-12 11:01:32 +0000[diff] [blame]769<h3>2.4.30: Dec 12 2002</h3>
770<ul>
771 <li>2.4.29 broke the python bindings, rereleasing</li>
772 <li>Improvement/fixes of the XML API generator, and couple of minor code
773 fixes.</li>
774</ul>
775
Daniel Veillard9b4bb4d2002-12-11 19:28:47 +0000[diff] [blame]776<h3>2.4.29: Dec 11 2002</h3>
777<ul>
778 <li>Windows fixes (Igor): Windows CE port, pthread linking, python bindings
779 (Stéphane Bidoul), Mingw (Magnus Henoch), and export list updates</li>
780 <li>Fix for prev in python bindings (ERDI Gergo)</li>
781 <li>Fix for entities handling (Marcus Clarke)</li>
782 <li>Refactored the XML and HTML dumps to a single code path, fixed XHTML1
783 dump</li>
784 <li>Fix for URI parsing when handling URNs with fragment identifiers</li>
785 <li>Fix for HTTP URL escaping problem</li>
786 <li>added an TextXmlReader (C#) like API (work in progress)</li>
787 <li>Rewrote the API in XML generation script, includes a C parser and saves
788 more informations needed for C# bindings</li>
789</ul>
790
Daniel Veillardf9c4cad2002-11-22 15:57:07 +0000[diff] [blame]791<h3>2.4.28: Nov 22 2002</h3>
792<ul>
793 <li>a couple of python binding fixes</li>
794 <li>2 bug fixes in the XML push parser</li>
795 <li>potential memory leak removed (Martin Stoilov)</li>
796 <li>fix to the configure script for Unix (Dimitri Papadopoulos)</li>
797 <li>added encoding support for XInclude parse="text"</li>
798 <li>autodetection of XHTML1 and specific serialization rules added</li>
Daniel Veillard9b4bb4d2002-12-11 19:28:47 +0000[diff] [blame]799 <li>nasty threading bug fixed (William Brack)</li>
Daniel Veillardf9c4cad2002-11-22 15:57:07 +0000[diff] [blame]800</ul>
801
Daniel Veillarddad3f682002-11-17 16:47:27 +0000[diff] [blame]802<h3>2.4.27: Nov 17 2002</h3>
803<ul>
804 <li>fixes for the Python bindings</li>
805 <li>a number of bug fixes: SGML catalogs, xmlParseBalancedChunkMemory(),
806 HTML parser, Schemas (Charles Bozeman), document fragment support
807 (Christian Glahn), xmlReconciliateNs (Brian Stafford), XPointer,
808 xmlFreeNode(), xmlSAXParseMemory (Peter Jones), xmlGetNodePath (Petr
809 Pajas), entities processing</li>
810 <li>added grep to xmllint --shell</li>
811 <li>VMS update patch from Craig A. Berry</li>
812 <li>cleanup of the Windows build with support for more compilers (Igor),
813 better thread support on Windows</li>
814 <li>cleanup of Unix Makefiles and spec file</li>
815 <li>Improvements to the documentation (John Fleck)</li>
816</ul>
817
Daniel Veillard48267432002-10-18 11:21:38 +0000[diff] [blame]818<h3>2.4.26: Oct 18 2002</h3>
819<ul>
820 <li>Patches for Windows CE port, improvements on Windows paths handling</li>
821 <li>Fixes to the validation code (DTD and Schemas), xmlNodeGetPath() ,
822 HTML serialization, Namespace compliance, and a number of small
823 problems</li>
824</ul>
825
Daniel Veillarde16b5742002-09-26 17:50:03 +0000[diff] [blame]826<h3>2.4.25: Sep 26 2002</h3>
827<ul>
828 <li>A number of bug fixes: XPath, validation, Python bindings, DOM and
829 tree, xmlI/O, Html</li>
830 <li>Serious rewrite of XInclude</li>
831 <li>Made XML Schemas regexp part of the default build and APIs, small fix
832 and improvement of the regexp core</li>
833 <li>Changed the validation code to reuse XML Schemas regexp APIs</li>
834 <li>Better handling of Windows file paths, improvement of Makefiles (Igor,
835 Daniel Gehriger, Mark Vakoc)</li>
836 <li>Improved the python I/O bindings, the tests, added resolver and regexp
Daniel Veillard321be0c2002-10-08 21:26:42 +0000[diff] [blame]837 APIs</li>
Daniel Veillarde16b5742002-09-26 17:50:03 +0000[diff] [blame]838 <li>New logos from Marc Liyanage</li>
839 <li>Tutorial improvements: John Fleck, Christopher Harris</li>
840 <li>Makefile: Fixes for AMD x86_64 (Mandrake), DESTDIR (Christophe
841 Merlet)</li>
842 <li>removal of all stderr/perror use for error reporting</li>
843 <li>Better error reporting: XPath and DTD validation</li>
844 <li>update of the trio portability layer (Bjorn Reese)</li>
845</ul>
846
Daniel Veillard42766c02002-08-22 20:52:17 +0000[diff] [blame]847<p><strong>2.4.24: Aug 22 2002</strong></p>
848<ul>
849 <li>XPath fixes (William), xf:escape-uri() (Wesley Terpstra)</li>
850 <li>Python binding fixes: makefiles (William), generator, rpm build, x86-64
851 (fcrozat)</li>
852 <li>HTML &lt;style&gt; and boolean attributes serializer fixes</li>
853 <li>C14N improvements by Aleksey</li>
Daniel Veillarde1662542002-08-28 11:50:59 +0000[diff] [blame]854 <li>doc cleanups: Rick Jones</li>
Daniel Veillard42766c02002-08-22 20:52:17 +0000[diff] [blame]855 <li>Windows compiler makefile updates: Igor and Elizabeth Barham</li>
856 <li>XInclude: implementation of fallback and xml:base fixup added</li>
857</ul>
858
Daniel Veillard782afda2002-07-08 15:12:49 +0000[diff] [blame]859<h3>2.4.23: July 6 2002</h3>
860<ul>
861 <li>performances patches: Peter Jacobi</li>
862 <li>c14n fixes, testsuite and performances: Aleksey Sanin</li>
863 <li>added xmlDocFormatDump: Chema Celorio</li>
864 <li>new tutorial: John Fleck</li>
865 <li>new hash functions and performances: Sander Vesik, portability fix from
866 Peter Jacobi</li>
867 <li>a number of bug fixes: XPath (William Brack, Richard Jinks), XML and
868 HTML parsers, ID lookup function</li>
869 <li>removal of all remaining sprintf: Aleksey Sanin</li>
870</ul>
871
Daniel Veillardc0801af2002-05-28 16:28:42 +0000[diff] [blame]872<h3>2.4.22: May 27 2002</h3>
873<ul>
874 <li>a number of bug fixes: configure scripts, base handling, parser, memory
875 usage, HTML parser, XPath, documentation (Christian Cornelssen),
Daniel Veillard21473672002-06-17 07:29:22 +0000[diff] [blame]876 indentation, URI parsing</li>
Daniel Veillardc0801af2002-05-28 16:28:42 +0000[diff] [blame]877 <li>Optimizations for XMLSec, fixing and making public some of the network
878 protocol handlers (Aleksey)</li>
879 <li>performance patch from Gary Pennington</li>
880 <li>Charles Bozeman provided date and time support for XML Schemas
881 datatypes</li>
882</ul>
883
Daniel Veillardcf27f7c2002-04-30 07:12:39 +0000[diff] [blame]884<h3>2.4.21: Apr 29 2002</h3>
885
886<p>This release is both a bug fix release and also contains the early XML
887Schemas <a href="http://www.w3.org/TR/xmlschema-1/">structures</a> and <a
888href="http://www.w3.org/TR/xmlschema-2/">datatypes</a> code, beware, all
889interfaces are likely to change, there is huge holes, it is clearly a work in
890progress and don't even think of putting this code in a production system,
Daniel Veillarde6d8e202002-05-02 06:11:10 +0000[diff] [blame]891it's actually not compiled in by default. The real fixes are:</p>
Daniel Veillardcf27f7c2002-04-30 07:12:39 +0000[diff] [blame]892<ul>
893 <li>a couple of bugs or limitations introduced in 2.4.20</li>
894 <li>patches for Borland C++ and MSC by Igor</li>
895 <li>some fixes on XPath strings and conformance patches by Richard
896 Jinks</li>
897 <li>patch from Aleksey for the ExcC14N specification</li>
898 <li>OSF/1 bug fix by Bjorn</li>
Daniel Veillardaf43f632002-03-08 15:05:20 +0000[diff] [blame]899</ul>
900
Daniel Veillarda7084cd2002-04-15 17:12:47 +0000[diff] [blame]901<h3>2.4.20: Apr 15 2002</h3>
902<ul>
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]903 <li>bug fixes: file descriptor leak, XPath, HTML output, DTD validation</li>
Daniel Veillarda7084cd2002-04-15 17:12:47 +0000[diff] [blame]904 <li>XPath conformance testing by Richard Jinks</li>
905 <li>Portability fixes: Solaris, MPE/iX, Windows, OSF/1, python bindings,
906 libxml.m4</li>
907</ul>
908
Daniel Veillard19274092002-03-25 16:48:03 +0000[diff] [blame]909<h3>2.4.19: Mar 25 2002</h3>
910<ul>
911 <li>bug fixes: half a dozen XPath bugs, Validation, ISO-Latin to UTF8
912 encoder</li>
913 <li>portability fixes in the HTTP code</li>
Daniel Veillardb2fb8ed2002-04-01 09:33:12 +0000[diff] [blame]914 <li>memory allocation checks using valgrind, and profiling tests</li>
Daniel Veillard19274092002-03-25 16:48:03 +0000[diff] [blame]915 <li>revamp of the Windows build and Makefiles</li>
916</ul>
917
Daniel Veillard34ce8be2002-03-18 19:37:11 +0000[diff] [blame]918<h3>2.4.18: Mar 18 2002</h3>
919<ul>
920 <li>bug fixes: tree, SAX, canonicalization, validation, portability,
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]921 XPath</li>
Daniel Veillard34ce8be2002-03-18 19:37:11 +0000[diff] [blame]922 <li>removed the --with-buffer option it was becoming unmaintainable</li>
923 <li>serious cleanup of the Python makefiles</li>
924 <li>speedup patch to XPath very effective for DocBook stylesheets</li>
925 <li>Fixes for Windows build, cleanup of the documentation</li>
926</ul>
927
Daniel Veillardaf43f632002-03-08 15:05:20 +0000[diff] [blame]928<h3>2.4.17: Mar 8 2002</h3>
929<ul>
930 <li>a lot of bug fixes, including "namespace nodes have no parents in
931 XPath"</li>
932 <li>fixed/improved the Python wrappers, added more examples and more
933 regression tests, XPath extension functions can now return node-sets</li>
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]934 <li>added the XML Canonicalization support from Aleksey Sanin</li>
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]935</ul>
936
Daniel Veillard5f4b5992002-02-20 10:22:49 +0000[diff] [blame]937<h3>2.4.16: Feb 20 2002</h3>
938<ul>
939 <li>a lot of bug fixes, most of them were triggered by the XML Testsuite
940 from OASIS and W3C. Compliance has been significantly improved.</li>
941 <li>a couple of portability fixes too.</li>
942</ul>
943
Daniel Veillard397ff112002-02-11 18:27:20 +0000[diff] [blame]944<h3>2.4.15: Feb 11 2002</h3>
945<ul>
946 <li>Fixed the Makefiles, especially the python module ones</li>
947 <li>A few bug fixes and cleanup</li>
948 <li>Includes cleanup</li>
949</ul>
950
Daniel Veillardb6c1e2f2002-02-08 14:52:52 +0000[diff] [blame]951<h3>2.4.14: Feb 8 2002</h3>
952<ul>
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]953 <li>Change of License to the <a
Daniel Veillardb6c1e2f2002-02-08 14:52:52 +0000[diff] [blame]954 href="http://www.opensource.org/licenses/mit-license.html">MIT
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]955 License</a> basically for integration in XFree86 codebase, and removing
956 confusion around the previous dual-licensing</li>
Daniel Veillardb6c1e2f2002-02-08 14:52:52 +0000[diff] [blame]957 <li>added Python bindings, beta software but should already be quite
958 complete</li>
959 <li>a large number of fixes and cleanups, especially for all tree
960 manipulations</li>
961 <li>cleanup of the headers, generation of a reference API definition in
962 XML</li>
963</ul>
964
965<h3>2.4.13: Jan 14 2002</h3>
Daniel Veillard744683d2002-01-14 17:30:20 +0000[diff] [blame]966<ul>
967 <li>update of the documentation: John Fleck and Charlie Bozeman</li>
968 <li>cleanup of timing code from Justin Fletcher</li>
969 <li>fixes for Windows and initial thread support on Win32: Igor and Serguei
970 Narojnyi</li>
971 <li>Cygwin patch from Robert Collins</li>
972 <li>added xmlSetEntityReferenceFunc() for Keith Isdale work on xsldbg</li>
973</ul>
974
Daniel Veillardef90ba72001-12-07 14:24:22 +0000[diff] [blame]975<h3>2.4.12: Dec 7 2001</h3>
976<ul>
977 <li>a few bug fixes: thread (Gary Pennington), xmllint (Geert Kloosterman),
978 XML parser (Robin Berjon), XPointer (Danny Jamshy), I/O cleanups
979 (robert)</li>
980 <li>Eric Lavigne contributed project files for MacOS</li>
981 <li>some makefiles cleanups</li>
982</ul>
983
Daniel Veillarda4871052001-11-26 13:19:48 +0000[diff] [blame]984<h3>2.4.11: Nov 26 2001</h3>
985<ul>
986 <li>fixed a couple of errors in the includes, fixed a few bugs, some code
987 cleanups</li>
988 <li>xmllint man pages improvement by Heiko Rupp</li>
989 <li>updated VMS build instructions from John A Fotheringham</li>
990 <li>Windows Makefiles updates from Igor</li>
991</ul>
992
Daniel Veillard43d3f612001-11-10 11:57:23 +0000[diff] [blame]993<h3>2.4.10: Nov 10 2001</h3>
994<ul>
995 <li>URI escaping fix (Joel Young)</li>
996 <li>added xmlGetNodePath() (for paths or XPointers generation)</li>
997 <li>Fixes namespace handling problems when using DTD and validation</li>
998 <li>improvements on xmllint: Morus Walter patches for --format and
999 --encode, Stefan Kost and Heiko Rupp improvements on the --shell</li>
1000 <li>fixes for xmlcatalog linking pointed by Weiqi Gao</li>
1001 <li>fixes to the HTML parser</li>
1002</ul>
1003
1004<h3>2.4.9: Nov 6 2001</h3>
1005<ul>
1006 <li>fixes more catalog bugs</li>
1007 <li>avoid a compilation problem, improve xmlGetLineNo()</li>
1008</ul>
1009
Daniel Veillarded421aa2001-11-04 21:22:45 +0000[diff] [blame]1010<h3>2.4.8: Nov 4 2001</h3>
1011<ul>
1012 <li>fixed SGML catalogs broken in previous release, updated xmlcatalog
1013 tool</li>
1014 <li>fixed a compile errors and some includes troubles.</li>
1015</ul>
1016
Daniel Veillard52dcab32001-10-30 12:51:17 +0000[diff] [blame]1017<h3>2.4.7: Oct 30 2001</h3>
1018<ul>
1019 <li>exported some debugging interfaces</li>
1020 <li>serious rewrite of the catalog code</li>
1021 <li>integrated Gary Pennington thread safety patch, added configure option
1022 and regression tests</li>
1023 <li>removed an HTML parser bug</li>
1024 <li>fixed a couple of potentially serious validation bugs</li>
1025 <li>integrated the SGML DocBook support in xmllint</li>
1026 <li>changed the nanoftp anonymous login passwd</li>
1027 <li>some I/O cleanup and a couple of interfaces for Perl wrapper</li>
1028 <li>general bug fixes</li>
1029 <li>updated xmllint man page by John Fleck</li>
1030 <li>some VMS and Windows updates</li>
1031</ul>
1032
Daniel Veillard60087f32001-10-10 09:45:09 +0000[diff] [blame]1033<h3>2.4.6: Oct 10 2001</h3>
1034<ul>
Daniel Veillard52dcab32001-10-30 12:51:17 +0000[diff] [blame]1035 <li>added an updated man pages by John Fleck</li>
Daniel Veillard60087f32001-10-10 09:45:09 +0000[diff] [blame]1036 <li>portability and configure fixes</li>
1037 <li>an infinite loop on the HTML parser was removed (William)</li>
1038 <li>Windows makefile patches from Igor</li>
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]1039 <li>fixed half a dozen bugs reported for libxml or libxslt</li>
Daniel Veillard60087f32001-10-10 09:45:09 +0000[diff] [blame]1040 <li>updated xmlcatalog to be able to modify SGML super catalogs</li>
1041</ul>
1042
Daniel Veillarddadd0872001-09-15 09:21:44 +0000[diff] [blame]1043<h3>2.4.5: Sep 14 2001</h3>
1044<ul>
1045 <li>Remove a few annoying bugs in 2.4.4</li>
1046 <li>forces the HTML serializer to output decimal charrefs since some
1047 version of Netscape can't handle hexadecimal ones</li>
1048</ul>
1049
1050<h3>1.8.16: Sep 14 2001</h3>
1051<ul>
1052 <li>maintenance release of the old libxml1 branch, couple of bug and
1053 portability fixes</li>
1054</ul>
1055
Daniel Veillard04382ae2001-09-12 18:51:30 +0000[diff] [blame]1056<h3>2.4.4: Sep 12 2001</h3>
1057<ul>
1058 <li>added --convert to xmlcatalog, bug fixes and cleanups of XML
1059 Catalog</li>
1060 <li>a few bug fixes and some portability changes</li>
1061 <li>some documentation cleanups</li>
1062</ul>
1063
Daniel Veillard39936902001-08-24 00:49:01 +0000[diff] [blame]1064<h3>2.4.3: Aug 23 2001</h3>
1065<ul>
1066 <li>XML Catalog support see the doc</li>
1067 <li>New NaN/Infinity floating point code</li>
1068 <li>A few bug fixes</li>
1069</ul>
1070
1071<h3>2.4.2: Aug 15 2001</h3>
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]1072<ul>
1073 <li>adds xmlLineNumbersDefault() to control line number generation</li>
1074 <li>lot of bug fixes</li>
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]1075 <li>the Microsoft MSC projects files should now be up to date</li>
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]1076 <li>inheritance of namespaces from DTD defaulted attributes</li>
1077 <li>fixes a serious potential security bug</li>
1078 <li>added a --format option to xmllint</li>
1079</ul>
1080
1081<h3>2.4.1: July 24 2001</h3>
1082<ul>
1083 <li>possibility to keep line numbers in the tree</li>
1084 <li>some computation NaN fixes</li>
1085 <li>extension of the XPath API</li>
1086 <li>cleanup for alpha and ia64 targets</li>
1087 <li>patch to allow saving through HTTP PUT or POST</li>
Daniel Veillard09ab7e12001-07-10 15:49:44 +0000[diff] [blame]1088</ul>
1089
1090<h3>2.4.0: July 10 2001</h3>
1091<ul>
1092 <li>Fixed a few bugs in XPath, validation, and tree handling.</li>
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]1093 <li>Fixed XML Base implementation, added a couple of examples to the
Daniel Veillard09ab7e12001-07-10 15:49:44 +0000[diff] [blame]1094 regression tests</li>
1095 <li>A bit of cleanup</li>
Daniel Veillardab8500d2000-10-15 21:06:19 +0000[diff] [blame]1096</ul>
1097
Daniel Veillard5b43fde2001-07-05 23:31:40 +0000[diff] [blame]1098<h3>2.3.14: July 5 2001</h3>
1099<ul>
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]1100 <li>fixed some entities problems and reduce memory requirement when
1101 substituting them</li>
Daniel Veillard5b43fde2001-07-05 23:31:40 +0000[diff] [blame]1102 <li>lots of improvements in the XPath queries interpreter can be
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]1103 substantially faster</li>
Daniel Veillard5b43fde2001-07-05 23:31:40 +0000[diff] [blame]1104 <li>Makefiles and configure cleanups</li>
1105 <li>Fixes to XPath variable eval, and compare on empty node set</li>
1106 <li>HTML tag closing bug fixed</li>
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]1107 <li>Fixed an URI reference computation problem when validating</li>
Daniel Veillard5b43fde2001-07-05 23:31:40 +0000[diff] [blame]1108</ul>
1109
Daniel Veillard2adbb512001-06-28 16:20:36 +0000[diff] [blame]1110<h3>2.3.13: June 28 2001</h3>
1111<ul>
1112 <li>2.3.12 configure.in was broken as well as the push mode XML parser</li>
1113 <li>a few more fixes for compilation on Windows MSC by Yon Derek</li>
1114</ul>
1115
1116<h3>1.8.14: June 28 2001</h3>
1117<ul>
1118 <li>Zbigniew Chyla gave a patch to use the old XML parser in push mode</li>
1119 <li>Small Makefile fix</li>
1120</ul>
1121
Daniel Veillard11648102001-06-26 16:08:24 +0000[diff] [blame]1122<h3>2.3.12: June 26 2001</h3>
1123<ul>
1124 <li>lots of cleanup</li>
1125 <li>a couple of validation fix</li>
1126 <li>fixed line number counting</li>
1127 <li>fixed serious problems in the XInclude processing</li>
1128 <li>added support for UTF8 BOM at beginning of entities</li>
1129 <li>fixed a strange gcc optimizer bugs in xpath handling of float, gcc-3.0
1130 miscompile uri.c (William), Thomas Leitner provided a fix for the
1131 optimizer on Tru64</li>
1132 <li>incorporated Yon Derek and Igor Zlatkovic fixes and improvements for
1133 compilation on Windows MSC</li>
1134 <li>update of libxml-doc.el (Felix Natter)</li>
1135 <li>fixed 2 bugs in URI normalization code</li>
1136</ul>
1137
Daniel Veillarde3c81b52001-06-17 14:50:34 +0000[diff] [blame]1138<h3>2.3.11: June 17 2001</h3>
1139<ul>
1140 <li>updates to trio, Makefiles and configure should fix some portability
1141 problems (alpha)</li>
1142 <li>fixed some HTML serialization problems (pre, script, and block/inline
1143 handling), added encoding aware APIs, cleanup of this code</li>
1144 <li>added xmlHasNsProp()</li>
1145 <li>implemented a specific PI for encoding support in the DocBook SGML
1146 parser</li>
1147 <li>some XPath fixes (-Infinity, / as a function parameter and namespaces
1148 node selection)</li>
1149 <li>fixed a performance problem and an error in the validation code</li>
1150 <li>fixed XInclude routine to implement the recursive behaviour</li>
1151 <li>fixed xmlFreeNode problem when libxml is included statically twice</li>
1152 <li>added --version to xmllint for bug reports</li>
1153</ul>
1154
Daniel Veillard2e4f1882001-06-01 10:11:57 +0000[diff] [blame]1155<h3>2.3.10: June 1 2001</h3>
1156<ul>
1157 <li>fixed the SGML catalog support</li>
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]1158 <li>a number of reported bugs got fixed, in XPath, iconv detection,
1159 XInclude processing</li>
Daniel Veillard2e4f1882001-06-01 10:11:57 +0000[diff] [blame]1160 <li>XPath string function should now handle unicode correctly</li>
1161</ul>
1162
Daniel Veillard4623acd2001-05-19 15:13:15 +0000[diff] [blame]1163<h3>2.3.9: May 19 2001</h3>
1164
1165<p>Lots of bugfixes, and added a basic SGML catalog support:</p>
1166<ul>
1167 <li>HTML push bugfix #54891 and another patch from Jonas Borgström</li>
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]1168 <li>some serious speed optimization again</li>
Daniel Veillard4623acd2001-05-19 15:13:15 +0000[diff] [blame]1169 <li>some documentation cleanups</li>
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]1170 <li>trying to get better linking on Solaris (-R)</li>
Daniel Veillard4623acd2001-05-19 15:13:15 +0000[diff] [blame]1171 <li>XPath API cleanup from Thomas Broyer</li>
1172 <li>Validation bug fixed #54631, added a patch from Gary Pennington, fixed
1173 xmlValidGetValidElements()</li>
1174 <li>Added an INSTALL file</li>
1175 <li>Attribute removal added to API: #54433</li>
1176 <li>added a basic support for SGML catalogs</li>
1177 <li>fixed xmlKeepBlanksDefault(0) API</li>
1178 <li>bugfix in xmlNodeGetLang()</li>
1179 <li>fixed a small configure portability problem</li>
1180 <li>fixed an inversion of SYSTEM and PUBLIC identifier in HTML document</li>
1181</ul>
1182
Daniel Veillarda265af72001-05-14 11:13:58 +0000[diff] [blame]1183<h3>1.8.13: May 14 2001</h3>
1184<ul>
1185 <li>bugfixes release of the old libxml1 branch used by Gnome</li>
1186</ul>
1187
Daniel Veillard3bbbe6f2001-05-03 11:15:37 +0000[diff] [blame]1188<h3>2.3.8: May 3 2001</h3>
1189<ul>
1190 <li>Integrated an SGML DocBook parser for the Gnome project</li>
1191 <li>Fixed a few things in the HTML parser</li>
1192 <li>Fixed some XPath bugs raised by XSLT use, tried to fix the floating
1193 point portability issue</li>
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]1194 <li>Speed improvement (8M/s for SAX, 3M/s for DOM, 1.5M/s for
1195 DOM+validation using the XML REC as input and a 700MHz celeron).</li>
Daniel Veillard3bbbe6f2001-05-03 11:15:37 +0000[diff] [blame]1196 <li>incorporated more Windows cleanup</li>
1197 <li>added xmlSaveFormatFile()</li>
1198 <li>fixed problems in copying nodes with entities references (gdome)</li>
1199 <li>removed some troubles surrounding the new validation module</li>
1200</ul>
1201
Daniel Veillarda41123c2001-04-22 19:31:20 +0000[diff] [blame]1202<h3>2.3.7: April 22 2001</h3>
1203<ul>
1204 <li>lots of small bug fixes, corrected XPointer</li>
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]1205 <li>Non deterministic content model validation support</li>
Daniel Veillarda41123c2001-04-22 19:31:20 +0000[diff] [blame]1206 <li>added xmlDocCopyNode for gdome2</li>
1207 <li>revamped the way the HTML parser handles end of tags</li>
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]1208 <li>XPath: corrections of namespaces support and number formatting</li>
Daniel Veillarda41123c2001-04-22 19:31:20 +0000[diff] [blame]1209 <li>Windows: Igor Zlatkovic patches for MSC compilation</li>
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]1210 <li>HTML output fixes from P C Chow and William M. Brack</li>
Daniel Veillarda41123c2001-04-22 19:31:20 +0000[diff] [blame]1211 <li>Improved validation speed sensible for DocBook</li>
1212 <li>fixed a big bug with ID declared in external parsed entities</li>
1213 <li>portability fixes, update of Trio from Bjorn Reese</li>
1214</ul>
1215
Daniel Veillardafc73112001-04-11 11:51:41 +0000[diff] [blame]1216<h3>2.3.6: April 8 2001</h3>
1217<ul>
1218 <li>Code cleanup using extreme gcc compiler warning options, found and
1219 cleared half a dozen potential problem</li>
1220 <li>the Eazel team found an XML parser bug</li>
1221 <li>cleaned up the user of some of the string formatting function. used the
1222 trio library code to provide the one needed when the platform is missing
1223 them</li>
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]1224 <li>xpath: removed a memory leak and fixed the predicate evaluation
1225 problem, extended the testsuite and cleaned up the result. XPointer seems
1226 broken ...</li>
Daniel Veillardafc73112001-04-11 11:51:41 +0000[diff] [blame]1227</ul>
1228
Daniel Veillard56a4cb82001-03-24 17:00:36 +0000[diff] [blame]1229<h3>2.3.5: Mar 23 2001</h3>
1230<ul>
1231 <li>Biggest change is separate parsing and evaluation of XPath expressions,
1232 there is some new APIs for this too</li>
1233 <li>included a number of bug fixes(XML push parser, 51876, notations,
1234 52299)</li>
1235 <li>Fixed some portability issues</li>
1236</ul>
1237
Daniel Veillarde356c282001-03-10 12:32:04 +0000[diff] [blame]1238<h3>2.3.4: Mar 10 2001</h3>
1239<ul>
1240 <li>Fixed bugs #51860 and #51861</li>
1241 <li>Added a global variable xmlDefaultBufferSize to allow default buffer
1242 size to be application tunable.</li>
1243 <li>Some cleanup in the validation code, still a bug left and this part
1244 should probably be rewritten to support ambiguous content model :-\</li>
1245 <li>Fix a couple of serious bugs introduced or raised by changes in 2.3.3
1246 parser</li>
1247 <li>Fixed another bug in xmlNodeGetContent()</li>
1248 <li>Bjorn fixed XPath node collection and Number formatting</li>
1249 <li>Fixed a loop reported in the HTML parsing</li>
1250 <li>blank space are reported even if the Dtd content model proves that they
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]1251 are formatting spaces, this is for XML conformance</li>
Daniel Veillarde356c282001-03-10 12:32:04 +0000[diff] [blame]1252</ul>
1253
Daniel Veillardb402c072001-03-01 17:28:58 +0000[diff] [blame]1254<h3>2.3.3: Mar 1 2001</h3>
1255<ul>
1256 <li>small change in XPath for XSLT</li>
1257 <li>documentation cleanups</li>
1258 <li>fix in validation by Gary Pennington</li>
1259 <li>serious parsing performances improvements</li>
1260</ul>
1261
Daniel Veillardec70e912001-02-26 20:10:45 +0000[diff] [blame]1262<h3>2.3.2: Feb 24 2001</h3>
Daniel Veillard71681102001-02-24 17:48:53 +0000[diff] [blame]1263<ul>
1264 <li>chasing XPath bugs, found a bunch, completed some TODO</li>
1265 <li>fixed a Dtd parsing bug</li>
1266 <li>fixed a bug in xmlNodeGetContent</li>
1267 <li>ID/IDREF support partly rewritten by Gary Pennington</li>
1268</ul>
1269
Daniel Veillardec70e912001-02-26 20:10:45 +0000[diff] [blame]1270<h3>2.3.1: Feb 15 2001</h3>
Daniel Veillard6e6a6cc2001-02-15 15:55:44 +0000[diff] [blame]1271<ul>
1272 <li>some XPath and HTML bug fixes for XSLT</li>
1273 <li>small extension of the hash table interfaces for DOM gdome2
1274 implementation</li>
1275 <li>A few bug fixes</li>
1276</ul>
1277
Daniel Veillardec70e912001-02-26 20:10:45 +0000[diff] [blame]1278<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]1279<ul>
1280 <li>Lots of XPath bug fixes</li>
1281 <li>Add a mode with Dtd lookup but without validation error reporting for
1282 XSLT</li>
1283 <li>Add support for text node without escaping (XSLT)</li>
1284 <li>bug fixes for xmlCheckFilename</li>
1285 <li>validation code bug fixes from Gary Pennington</li>
1286 <li>Patch from Paul D. Smith correcting URI path normalization</li>
1287 <li>Patch to allow simultaneous install of libxml-devel and
1288 libxml2-devel</li>
1289 <li>the example Makefile is now fixed</li>
1290 <li>added HTML to the RPM packages</li>
1291 <li>tree copying bugfixes</li>
1292 <li>updates to Windows makefiles</li>
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]1293 <li>optimization patch from Bjorn Reese</li>
Daniel Veillard6e6a6cc2001-02-15 15:55:44 +0000[diff] [blame]1294</ul>
1295
Daniel Veillardec70e912001-02-26 20:10:45 +0000[diff] [blame]1296<h3>2.2.11: Jan 4 2001</h3>
Daniel Veillard503b8932001-01-05 06:36:31 +0000[diff] [blame]1297<ul>
1298 <li>bunch of bug fixes (memory I/O, xpath, ftp/http, ...)</li>
1299 <li>added htmlHandleOmittedElem()</li>
1300 <li>Applied Bjorn Reese's IPV6 first patch</li>
1301 <li>Applied Paul D. Smith patches for validation of XInclude results</li>
Daniel Veillard82687162001-01-22 15:32:01 +0000[diff] [blame]1302 <li>added XPointer xmlns() new scheme support</li>
Daniel Veillard503b8932001-01-05 06:36:31 +0000[diff] [blame]1303</ul>
1304
Daniel Veillard2ddd23d2000-11-25 10:42:19 +0000[diff] [blame]1305<h3>2.2.10: Nov 25 2000</h3>
Daniel Veillard9d343c42000-11-25 10:12:43 +0000[diff] [blame]1306<ul>
1307 <li>Fix the Windows problems of 2.2.8</li>
1308 <li>integrate OpenVMS patches</li>
1309 <li>better handling of some nasty HTML input</li>
1310 <li>Improved the XPointer implementation</li>
1311 <li>integrate a number of provided patches</li>
1312</ul>
1313
Daniel Veillard2ddd23d2000-11-25 10:42:19 +0000[diff] [blame]1314<h3>2.2.9: Nov 25 2000</h3>
1315<ul>
1316 <li>erroneous release :-(</li>
1317</ul>
1318
Daniel Veillard28929b22000-11-13 18:22:49 +0000[diff] [blame]1319<h3>2.2.8: Nov 13 2000</h3>
1320<ul>
1321 <li>First version of <a href="http://www.w3.org/TR/xinclude">XInclude</a>
1322 support</li>
1323 <li>Patch in conditional section handling</li>
1324 <li>updated MS compiler project</li>
1325 <li>fixed some XPath problems</li>
1326 <li>added an URI escaping function</li>
1327 <li>some other bug fixes</li>
1328</ul>
1329
1330<h3>2.2.7: Oct 31 2000</h3>
1331<ul>
1332 <li>added message redirection</li>
1333 <li>XPath improvements (thanks TOM !)</li>
1334 <li>xmlIOParseDTD() added</li>
1335 <li>various small fixes in the HTML, URI, HTTP and XPointer support</li>
1336 <li>some cleanup of the Makefile, autoconf and the distribution content</li>
1337</ul>
1338
Daniel Veillard29a11cc2000-10-25 13:32:39 +0000[diff] [blame]1339<h3>2.2.6: Oct 25 2000:</h3>
1340<ul>
1341 <li>Added an hash table module, migrated a number of internal structure to
1342 those</li>
1343 <li>Fixed a posteriori validation problems</li>
1344 <li>HTTP module cleanups</li>
1345 <li>HTML parser improvements (tag errors, script/style handling, attribute
1346 normalization)</li>
1347 <li>coalescing of adjacent text nodes</li>
1348 <li>couple of XPath bug fixes, exported the internal API</li>
1349</ul>
1350
Daniel Veillardab8500d2000-10-15 21:06:19 +0000[diff] [blame]1351<h3>2.2.5: Oct 15 2000:</h3>
Daniel Veillard4c3a2031999-11-19 17:46:26 +0000[diff] [blame]1352<ul>
Daniel Veillard189446d2000-10-13 10:23:06 +0000[diff] [blame]1353 <li>XPointer implementation and testsuite</li>
1354 <li>Lot of XPath fixes, added variable and functions registration, more
1355 tests</li>
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]1356 <li>Portability fixes, lots of enhancements toward an easy Windows build
1357 and release</li>
Daniel Veillard189446d2000-10-13 10:23:06 +0000[diff] [blame]1358 <li>Late validation fixes</li>
1359 <li>Integrated a lot of contributed patches</li>
1360 <li>added memory management docs</li>
Daniel Veillardab8500d2000-10-15 21:06:19 +0000[diff] [blame]1361 <li>a performance problem when using large buffer seems fixed</li>
Daniel Veillard189446d2000-10-13 10:23:06 +0000[diff] [blame]1362</ul>
1363
1364<h3>2.2.4: Oct 1 2000:</h3>
1365<ul>
1366 <li>main XPath problem fixed</li>
1367 <li>Integrated portability patches for Windows</li>
1368 <li>Serious bug fixes on the URI and HTML code</li>
Daniel Veillard361d8452000-04-03 19:48:13 +0000[diff] [blame]1369</ul>
1370
Daniel Veillardd5f97f82000-09-17 16:38:14 +0000[diff] [blame]1371<h3>2.2.3: Sep 17 2000</h3>
1372<ul>
1373 <li>bug fixes</li>
1374 <li>cleanup of entity handling code</li>
1375 <li>overall review of all loops in the parsers, all sprintf usage has been
1376 checked too</li>
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]1377 <li>Far better handling of larges Dtd. Validating against DocBook XML Dtd
Daniel Veillardd5f97f82000-09-17 16:38:14 +0000[diff] [blame]1378 works smoothly now.</li>
1379</ul>
1380
1381<h3>1.8.10: Sep 6 2000</h3>
1382<ul>
1383 <li>bug fix release for some Gnome projects</li>
1384</ul>
1385
1386<h3>2.2.2: August 12 2000</h3>
Daniel Veillard786d7c82000-08-12 23:38:57 +0000[diff] [blame]1387<ul>
1388 <li>mostly bug fixes</li>
Daniel Veillardec78c0f2000-08-25 10:25:23 +0000[diff] [blame]1389 <li>started adding routines to access xml parser context options</li>
Daniel Veillard786d7c82000-08-12 23:38:57 +0000[diff] [blame]1390</ul>
1391
Daniel Veillardd5f97f82000-09-17 16:38:14 +0000[diff] [blame]1392<h3>2.2.1: July 21 2000</h3>
Daniel Veillarda2679fa2000-07-22 02:38:15 +0000[diff] [blame]1393<ul>
1394 <li>a purely bug fixes release</li>
1395 <li>fixed an encoding support problem when parsing from a memory block</li>
1396 <li>fixed a DOCTYPE parsing problem</li>
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]1397 <li>removed a bug in the function allowing to override the memory
1398 allocation routines</li>
Daniel Veillarda2679fa2000-07-22 02:38:15 +0000[diff] [blame]1399</ul>
1400
Daniel Veillardd5f97f82000-09-17 16:38:14 +0000[diff] [blame]1401<h3>2.2.0: July 14 2000</h3>
Daniel Veillard94e90602000-07-17 14:38:19 +0000[diff] [blame]1402<ul>
1403 <li>applied a lot of portability fixes</li>
1404 <li>better encoding support/cleanup and saving (content is now always
1405 encoded in UTF-8)</li>
1406 <li>the HTML parser now correctly handles encodings</li>
1407 <li>added xmlHasProp()</li>
1408 <li>fixed a serious problem with &amp;#38;</li>
1409 <li>propagated the fix to FTP client</li>
1410 <li>cleanup, bugfixes, etc ...</li>
1411 <li>Added a page about <a href="encoding.html">libxml Internationalization
1412 support</a></li>
1413</ul>
1414
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]1415<h3>1.8.9: July 9 2000</h3>
1416<ul>
1417 <li>fixed the spec the RPMs should be better</li>
1418 <li>fixed a serious bug in the FTP implementation, released 1.8.9 to solve
1419 rpmfind users problem</li>
1420</ul>
1421
Daniel Veillard6388e172000-07-03 16:07:19 +0000[diff] [blame]1422<h3>2.1.1: July 1 2000</h3>
1423<ul>
1424 <li>fixes a couple of bugs in the 2.1.0 packaging</li>
1425 <li>improvements on the HTML parser</li>
1426</ul>
1427
Daniel Veillard3f6f7f62000-06-30 17:58:25 +0000[diff] [blame]1428<h3>2.1.0 and 1.8.8: June 29 2000</h3>
1429<ul>
Daniel Veillardc0801af2002-05-28 16:28:42 +0000[diff] [blame]1430 <li>1.8.8 is mostly a commodity package for upgrading to libxml2 according
1431 to <a href="upgrade.html">new instructions</a>. It fixes a nasty problem
Daniel Veillard3f6f7f62000-06-30 17:58:25 +0000[diff] [blame]1432 about &amp;#38; charref parsing</li>
1433 <li>2.1.0 also ease the upgrade from libxml v1 to the recent version. it
1434 also contains numerous fixes and enhancements:
1435 <ul>
1436 <li>added xmlStopParser() to stop parsing</li>
1437 <li>improved a lot parsing speed when there is large CDATA blocs</li>
1438 <li>includes XPath patches provided by Picdar Technology</li>
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]1439 <li>tried to fix as much as possible DTD validation and namespace
Daniel Veillard3f6f7f62000-06-30 17:58:25 +0000[diff] [blame]1440 related problems</li>
1441 <li>output to a given encoding has been added/tested</li>
1442 <li>lot of various fixes</li>
1443 </ul>
1444 </li>
1445</ul>
1446
Daniel Veillarde0aed302000-04-16 08:52:20 +0000[diff] [blame]1447<h3>2.0.0: Apr 12 2000</h3>
Daniel Veillard361d8452000-04-03 19:48:13 +0000[diff] [blame]1448<ul>
1449 <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]1450 idea to check the 1.x to 2.x upgrade instructions. NOTE: while initially
1451 scheduled for Apr 3 the release occurred only on Apr 12 due to massive
Daniel Veillarde0aed302000-04-16 08:52:20 +0000[diff] [blame]1452 workload.</li>
Daniel Veillard361d8452000-04-03 19:48:13 +0000[diff] [blame]1453 <li>The include are now located under $prefix/include/libxml (instead of
Daniel Veillarde0aed302000-04-16 08:52:20 +0000[diff] [blame]1454 $prefix/include/gnome-xml), they also are referenced by
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]1455 <pre>#include &lt;libxml/xxx.h&gt;</pre>
Daniel Veillarde0aed302000-04-16 08:52:20 +0000[diff] [blame]1456 <p>instead of</p>
Daniel Veillard361d8452000-04-03 19:48:13 +0000[diff] [blame]1457 <pre>#include "xxx.h"</pre>
1458 </li>
Daniel Veillard8f621982000-03-20 13:07:15 +0000[diff] [blame]1459 <li>a new URI module for parsing URIs and following strictly RFC 2396</li>
1460 <li>the memory allocation routines used by libxml can now be overloaded
1461 dynamically by using xmlMemSetup()</li>
Daniel Veillard361d8452000-04-03 19:48:13 +0000[diff] [blame]1462 <li>The previously CVS only tool tester has been renamed
1463 <strong>xmllint</strong> and is now installed as part of the libxml2
1464 package</li>
Daniel Veillarde0aed302000-04-16 08:52:20 +0000[diff] [blame]1465 <li>The I/O interface has been revamped. There is now ways to plug in
1466 specific I/O modules, either at the URI scheme detection level using
1467 xmlRegisterInputCallbacks() or by passing I/O functions when creating a
1468 parser context using xmlCreateIOParserCtxt()</li>
1469 <li>there is a C preprocessor macro LIBXML_VERSION providing the version
1470 number of the libxml module in use</li>
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]1471 <li>a number of optional features of libxml can now be excluded at
1472 configure time (FTP/HTTP/HTML/XPath/Debug)</li>
Daniel Veillardedfb29b2000-03-14 19:59:05 +0000[diff] [blame]1473</ul>
1474
1475<h3>2.0.0beta: Mar 14 2000</h3>
1476<ul>
1477 <li>This is a first Beta release of libxml version 2</li>
Daniel Veillarde356c282001-03-10 12:32:04 +0000[diff] [blame]1478 <li>It's available only from<a href="ftp://xmlsoft.org/">xmlsoft.org
1479 FTP</a>, it's packaged as libxml2-2.0.0beta and available as tar and
1480 RPMs</li>
Daniel Veillardedfb29b2000-03-14 19:59:05 +0000[diff] [blame]1481 <li>This version is now the head in the Gnome CVS base, the old one is
1482 available under the tag LIB_XML_1_X</li>
Daniel Veillardc0801af2002-05-28 16:28:42 +0000[diff] [blame]1483 <li>This includes a very large set of changes. From a programmatic point
1484 of view applications should not have to be modified too much, check the
1485 <a href="upgrade.html">upgrade page</a></li>
Daniel Veillardedfb29b2000-03-14 19:59:05 +0000[diff] [blame]1486 <li>Some interfaces may changes (especially a bit about encoding).</li>
1487 <li>the updates includes:
Daniel Veillard6c8b1172000-03-01 00:40:41 +0000[diff] [blame]1488 <ul>
Daniel Veillardedfb29b2000-03-14 19:59:05 +0000[diff] [blame]1489 <li>fix I18N support. ISO-Latin-x/UTF-8/UTF-16 (nearly) seems correctly
1490 handled now</li>
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]1491 <li>Better handling of entities, especially well-formedness checking
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]1492 and proper PEref extensions in external subsets</li>
Daniel Veillard6c8b1172000-03-01 00:40:41 +0000[diff] [blame]1493 <li>DTD conditional sections</li>
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]1494 <li>Validation now correctly handle entities content</li>
Daniel Veillard6c8b1172000-03-01 00:40:41 +0000[diff] [blame]1495 <li><a href="http://rpmfind.net/tools/gdome/messages/0039.html">change
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]1496 structures to accommodate DOM</a></li>
Daniel Veillard6c8b1172000-03-01 00:40:41 +0000[diff] [blame]1497 </ul>
1498 </li>
Daniel Veillardedfb29b2000-03-14 19:59:05 +0000[diff] [blame]1499 <li>Serious progress were made toward compliance, <a
1500 href="conf/result.html">here are the result of the test</a> against the
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]1501 OASIS testsuite (except the Japanese tests since I don't support that
Daniel Veillardedfb29b2000-03-14 19:59:05 +0000[diff] [blame]1502 encoding yet). This URL is rebuilt every couple of hours using the CVS
1503 head version.</li>
Daniel Veillarde41f2b72000-01-30 20:00:07 +0000[diff] [blame]1504</ul>
1505
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]1506<h3>1.8.7: Mar 6 2000</h3>
1507<ul>
1508 <li>This is a bug fix release:</li>
1509 <li>It is possible to disable the ignorable blanks heuristic used by
1510 libxml-1.x, a new function xmlKeepBlanksDefault(0) will allow this. Note
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]1511 that for adherence to XML spec, this behaviour will be disabled by
1512 default in 2.x . The same function will allow to keep compatibility for
1513 old code.</li>
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]1514 <li>Blanks in &lt;a&gt; &lt;/a&gt; constructs are not ignored anymore,
1515 avoiding heuristic is really the Right Way :-\</li>
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]1516 <li>The unchecked use of snprintf which was breaking libxml-1.8.6
1517 compilation on some platforms has been fixed</li>
1518 <li>nanoftp.c nanohttp.c: Fixed '#' and '?' stripping when processing
1519 URIs</li>
1520</ul>
1521
Daniel Veillarde41f2b72000-01-30 20:00:07 +0000[diff] [blame]1522<h3>1.8.6: Jan 31 2000</h3>
1523<ul>
1524 <li>added a nanoFTP transport module, debugged until the new version of <a
1525 href="http://rpmfind.net/linux/rpm2html/rpmfind.html">rpmfind</a> can use
1526 it without troubles</li>
Daniel Veillardda07c342000-01-25 18:31:22 +0000[diff] [blame]1527</ul>
1528
1529<h3>1.8.5: Jan 21 2000</h3>
1530<ul>
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]1531 <li>adding APIs to parse a well balanced chunk of XML (production <a
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]1532 href="http://www.w3.org/TR/REC-xml#NT-content">[43] content</a> of the
1533 XML spec)</li>
Daniel Veillard461a66c2000-01-18 18:01:01 +0000[diff] [blame]1534 <li>fixed a hideous bug in xmlGetProp pointed by Rune.Djurhuus@fast.no</li>
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]1535 <li>Jody Goldberg &lt;jgoldberg@home.com&gt; provided another patch trying
1536 to solve the zlib checks problems</li>
Daniel Veillard461a66c2000-01-18 18:01:01 +0000[diff] [blame]1537 <li>The current state in gnome CVS base is expected to ship as 1.8.5 with
1538 gnumeric soon</li>
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]1539</ul>
1540
1541<h3>1.8.4: Jan 13 2000</h3>
1542<ul>
1543 <li>bug fixes, reintroduced xmlNewGlobalNs(), fixed xmlNewNs()</li>
1544 <li>all exit() call should have been removed from libxml</li>
1545 <li>fixed a problem with INCLUDE_WINSOCK on WIN32 platform</li>
1546 <li>added newDocFragment()</li>
Daniel Veillardf84f71f2000-01-05 19:54:23 +0000[diff] [blame]1547</ul>
1548
1549<h3>1.8.3: Jan 5 2000</h3>
1550<ul>
1551 <li>a Push interface for the XML and HTML parsers</li>
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]1552 <li>a shell-like interface to the document tree (try tester --shell :-)</li>
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]1553 <li>lots of bug fixes and improvement added over XMas holidays</li>
Daniel Veillard437b87b2000-01-03 17:30:46 +0000[diff] [blame]1554 <li>fixed the DTD parsing code to work with the xhtml DTD</li>
Daniel Veillardf84f71f2000-01-05 19:54:23 +0000[diff] [blame]1555 <li>added xmlRemoveProp(), xmlRemoveID() and xmlRemoveRef()</li>
1556 <li>Fixed bugs in xmlNewNs()</li>
Daniel Veillard437b87b2000-01-03 17:30:46 +0000[diff] [blame]1557 <li>External entity loading code has been revamped, now it uses
Daniel Veillardf84f71f2000-01-05 19:54:23 +0000[diff] [blame]1558 xmlLoadExternalEntity(), some fix on entities processing were added</li>
Daniel Veillard437b87b2000-01-03 17:30:46 +0000[diff] [blame]1559 <li>cleaned up WIN32 includes of socket stuff</li>
Daniel Veillard5cb5ab81999-12-21 15:35:29 +0000[diff] [blame]1560</ul>
1561
1562<h3>1.8.2: Dec 21 1999</h3>
1563<ul>
Daniel Veillardb24054a1999-12-18 15:32:46 +0000[diff] [blame]1564 <li>I got another problem with includes and C++, I hope this issue is fixed
1565 for good this time</li>
Daniel Veillard5cb5ab81999-12-21 15:35:29 +0000[diff] [blame]1566 <li>Added a few tree modification functions: xmlReplaceNode,
1567 xmlAddPrevSibling, xmlAddNextSibling, xmlNodeSetName and
1568 xmlDocSetRootElement</li>
1569 <li>Tried to improve the HTML output with help from <a
1570 href="mailto:clahey@umich.edu">Chris Lahey</a></li>
Daniel Veillarde4e51311999-12-18 15:32:46 +0000[diff] [blame]1571</ul>
Daniel Veillardb24054a1999-12-18 15:32:46 +0000[diff] [blame]1572
Daniel Veillarde4e51311999-12-18 15:32:46 +0000[diff] [blame]1573<h3>1.8.1: Dec 18 1999</h3>
1574<ul>
1575 <li>various patches to avoid troubles when using libxml with C++ compilers
1576 the "namespace" keyword and C escaping in include files</li>
1577 <li>a problem in one of the core macros IS_CHAR was corrected</li>
1578 <li>fixed a bug introduced in 1.8.0 breaking default namespace processing,
1579 and more specifically the Dia application</li>
Daniel Veillard944b5ff1999-12-15 19:08:24 +0000[diff] [blame]1580 <li>fixed a posteriori validation (validation after parsing, or by using a
1581 Dtd not specified in the original document)</li>
Daniel Veillardb24054a1999-12-18 15:32:46 +0000[diff] [blame]1582 <li>fixed a bug in</li>
Daniel Veillard10a2c651999-12-12 13:03:50 +0000[diff] [blame]1583</ul>
1584
1585<h3>1.8.0: Dec 12 1999</h3>
1586<ul>
1587 <li>cleanup, especially memory wise</li>
1588 <li>the parser should be more reliable, especially the HTML one, it should
1589 not crash, whatever the input !</li>
1590 <li>Integrated various patches, especially a speedup improvement for large
1591 dataset from <a href="mailto:cnygard@bellatlantic.net">Carl Nygard</a>,
1592 configure with --with-buffers to enable them.</li>
1593 <li>attribute normalization, oops should have been added long ago !</li>
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]1594 <li>attributes defaulted from DTDs should be available, xmlSetProp() now
1595 does entities escaping by default.</li>
Daniel Veillard4c3a2031999-11-19 17:46:26 +0000[diff] [blame]1596</ul>
Daniel Veillard35008381999-10-25 13:15:52 +0000[diff] [blame]1597
1598<h3>1.7.4: Oct 25 1999</h3>
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]1599<ul>
Daniel Veillard35008381999-10-25 13:15:52 +0000[diff] [blame]1600 <li>Lots of HTML improvement</li>
1601 <li>Fixed some errors when saving both XML and HTML</li>
1602 <li>More examples, the regression tests should now look clean</li>
1603 <li>Fixed a bug with contiguous charref</li>
1604</ul>
1605
1606<h3>1.7.3: Sep 29 1999</h3>
1607<ul>
1608 <li>portability problems fixed</li>
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]1609 <li>snprintf was used unconditionally, leading to link problems on system
Daniel Veillard35008381999-10-25 13:15:52 +0000[diff] [blame]1610 were it's not available, fixed</li>
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]1611</ul>
1612
1613<h3>1.7.1: Sep 24 1999</h3>
1614<ul>
1615 <li>The basic type for strings manipulated by libxml has been renamed in
1616 1.7.1 from <strong>CHAR</strong> to <strong>xmlChar</strong>. The reason
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]1617 is that CHAR was conflicting with a predefined type on Windows. However
1618 on non WIN32 environment, compatibility is provided by the way of a
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]1619 <strong>#define </strong>.</li>
1620 <li>Changed another error : the use of a structure field called errno, and
1621 leading to troubles on platforms where it's a macro</li>
1622</ul>
1623
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]1624<h3>1.7.0: Sep 23 1999</h3>
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]1625<ul>
1626 <li>Added the ability to fetch remote DTD or parsed entities, see the <a
Daniel Veillard9cb5ff42001-01-29 08:22:21 +0000[diff] [blame]1627 href="html/libxml-nanohttp.html">nanohttp</a> module.</li>
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]1628 <li>Added an errno to report errors by another mean than a simple printf
1629 like callback</li>
1630 <li>Finished ID/IDREF support and checking when validation</li>
1631 <li>Serious memory leaks fixed (there is now a <a
Daniel Veillard9cb5ff42001-01-29 08:22:21 +0000[diff] [blame]1632 href="html/libxml-xmlmemory.html">memory wrapper</a> module)</li>
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]1633 <li>Improvement of <a href="http://www.w3.org/TR/xpath">XPath</a>
1634 implementation</li>
1635 <li>Added an HTML parser front-end</li>
1636</ul>
1637
1638<h2><a name="XML">XML</a></h2>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]1639
Daniel Veillard402e8c82000-02-29 22:57:47 +0000[diff] [blame]1640<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]1641markup-based structured documents. Here is <a name="example">an example XML
1642document</a>:</p>
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]1643<pre>&lt;?xml version="1.0"?&gt;
1644&lt;EXAMPLE prop1="gnome is great" prop2="&amp;amp; linux too"&gt;
1645 &lt;head&gt;
1646 &lt;title&gt;Welcome to Gnome&lt;/title&gt;
1647 &lt;/head&gt;
1648 &lt;chapter&gt;
1649 &lt;title&gt;The Linux adventure&lt;/title&gt;
1650 &lt;p&gt;bla bla bla ...&lt;/p&gt;
1651 &lt;image href="linus.gif"/&gt;
1652 &lt;p&gt;...&lt;/p&gt;
1653 &lt;/chapter&gt;
1654&lt;/EXAMPLE&gt;</pre>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]1655
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]1656<p>The first line specifies that it is an XML document and gives useful
Daniel Veillard42766c02002-08-22 20:52:17 +0000[diff] [blame]1657information about its encoding. Then the rest of the document is a text
1658format whose structure is specified by tags between brackets. <strong>Each
1659tag opened has to be closed</strong>. XML is pedantic about this. However, if
1660a tag is empty (no content), a single tag can serve as both the opening and
1661closing tag if it ends with <code>/&gt;</code> rather than with
1662<code>&gt;</code>. Note that, for example, the image tag has no content (just
1663an attribute) and is closed by ending the tag with <code>/&gt;</code>.</p>
Daniel Veillardccb09631998-10-27 06:21:04 +0000[diff] [blame]1664
Daniel Veillard42766c02002-08-22 20:52:17 +0000[diff] [blame]1665<p>XML can be applied successfully to a wide range of tasks, ranging from
1666long term structured document maintenance (where it follows the steps of
1667SGML) to simple data encoding mechanisms like configuration file formatting
1668(glade), spreadsheets (gnumeric), or even shorter lived documents such as
1669WebDAV where it is used to encode remote calls between a client and a
1670server.</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]1671
Daniel Veillard82687162001-01-22 15:32:01 +0000[diff] [blame]1672<h2><a name="XSLT">XSLT</a></h2>
1673
Daniel Veillard6e6a6cc2001-02-15 15:55:44 +0000[diff] [blame]1674<p>Check <a href="http://xmlsoft.org/XSLT">the separate libxslt page</a></p>
1675
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]1676<p><a href="http://www.w3.org/TR/xslt">XSL Transformations</a>, is a
1677language for transforming XML documents into other XML documents (or
1678HTML/textual output).</p>
Daniel Veillard82687162001-01-22 15:32:01 +0000[diff] [blame]1679
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]1680<p>A separate library called libxslt is available implementing XSLT-1.0
1681for libxml2. This module "libxslt" too can be found in the Gnome CVS base.</p>
Daniel Veillard82687162001-01-22 15:32:01 +0000[diff] [blame]1682
Daniel Veillard383b1472001-01-23 11:39:52 +0000[diff] [blame]1683<p>You can check the <a
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]1684href="http://cvs.gnome.org/lxr/source/libxslt/FEATURES">features</a>
1685supported and the progresses on the <a
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]1686href="http://cvs.gnome.org/lxr/source/libxslt/ChangeLog"
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]1687name="Changelog">Changelog</a>.</p>
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]1688
1689<h2><a name="Python">Python and bindings</a></h2>
1690
Daniel Veillard42766c02002-08-22 20:52:17 +0000[diff] [blame]1691<p>There are a number of language bindings and wrappers available for
1692libxml2, the list below is not exhaustive. Please contact the <a
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]1693href="http://mail.gnome.org/mailman/listinfo/xml-bindings">xml-bindings@gnome.org</a>
1694(<a href="http://mail.gnome.org/archives/xml-bindings/">archives</a>) in
1695order to get updates to this list or to discuss the specific topic of libxml2
1696or libxslt wrappers or bindings:</p>
1697<ul>
Daniel Veillardc14401e2002-11-20 14:28:17 +0000[diff] [blame]1698 <li><a href="http://libxmlplusplus.sourceforge.net/">Libxml++</a> seems the
1699 most up-to-date C++ bindings for libxml2, check the <a
1700 href="http://libxmlplusplus.sourceforge.net/reference/html/hierarchy.html">documentation</a>
1701 and the <a
1702 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]1703 <li>There is another <a href="http://libgdome-cpp.berlios.de/">C++ wrapper
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]1704 based on the gdome2 bindings</a> maintained by Tobias Peters.</li>
Daniel Veillard9b6fd302002-05-13 12:06:47 +0000[diff] [blame]1705 <li>and a third C++ wrapper by Peter Jones &lt;pjones@pmade.org&gt;
1706 <p>Website: <a
1707 href="http://pmade.org/pjones/software/xmlwrapp/">http://pmade.org/pjones/software/xmlwrapp/</a></p>
1708 </li>
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]1709 <li><a
1710 href="http://mail.gnome.org/archives/xml/2001-March/msg00014.html">Matt
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]1711 Sergeant</a> developed <a
1712 href="http://axkit.org/download/">XML::LibXSLT</a>, a Perl wrapper for
Daniel Veillardaf43f632002-03-08 15:05:20 +0000[diff] [blame]1713 libxml2/libxslt as part of the <a href="http://axkit.com/">AxKit XML
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]1714 application server</a>.</li>
Daniel Veillard21473672002-06-17 07:29:22 +0000[diff] [blame]1715 <li><a href="mailto:dkuhlman@cutter.rexx.com">Dave Kuhlman</a> provides an
Daniel Veillardaf43f632002-03-08 15:05:20 +0000[diff] [blame]1716 earlier version of the libxml/libxslt <a
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]1717 href="http://www.rexx.com/~dkuhlman">wrappers for Python</a>.</li>
Daniel Veillard21473672002-06-17 07:29:22 +0000[diff] [blame]1718 <li>Gopal.V and Peter Minten develop <a
1719 href="http://savannah.gnu.org/projects/libxmlsharp">libxml#</a>, a set of
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]1720 C# libxml2 bindings.</li>
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]1721 <li>Petr Kozelka provides <a
1722 href="http://sourceforge.net/projects/libxml2-pas">Pascal units to glue
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]1723 libxml2</a> with Kylix, Delphi and other Pascal compilers.</li>
Daniel Veillardb2fb8ed2002-04-01 09:33:12 +0000[diff] [blame]1724 <li>Uwe Fechner also provides <a
1725 href="http://sourceforge.net/projects/idom2-pas/">idom2</a>, a DOM2
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]1726 implementation for Kylix2/D5/D6 from Borland.</li>
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]1727 <li>Wai-Sun "Squidster" Chia provides <a
1728 href="http://www.rubycolor.org/arc/redist/">bindings for Ruby</a> and
1729 libxml2 bindings are also available in Ruby through the <a
1730 href="http://libgdome-ruby.berlios.de/">libgdome-ruby</a> module
1731 maintained by Tobias Peters.</li>
Daniel Veillardaf43f632002-03-08 15:05:20 +0000[diff] [blame]1732 <li>Steve Ball and contributors maintains <a
1733 href="http://tclxml.sourceforge.net/">libxml2 and libxslt bindings for
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]1734 Tcl</a>.</li>
Daniel Veillardaf43f632002-03-08 15:05:20 +0000[diff] [blame]1735 <li>There is support for libxml2 in the DOM module of PHP.</li>
Daniel Veillard41b01a82003-02-27 11:09:06 +0000[diff] [blame]1736 <li><a href="http://savannah.gnu.org/projects/classpathx/">LibxmlJ</a> is
Daniel Veillard806cada2003-03-19 21:58:59 +0000[diff] [blame]1737 an effort to create a 100% JAXP-compatible Java wrapper for libxml2 and
1738 libxslt as part of GNU ClasspathX project.</li>
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]1739</ul>
1740
Daniel Veillardc0801af2002-05-28 16:28:42 +0000[diff] [blame]1741<p>The distribution includes a set of Python bindings, which are guaranteed
1742to be maintained as part of the library in the future, though the Python
Daniel Veillard41b01a82003-02-27 11:09:06 +0000[diff] [blame]1743interface have not yet reached the completeness of the C API.</p>
Daniel Veillard7b4b2f92003-01-06 13:11:20 +0000[diff] [blame]1744
Daniel Veillard27907c72002-12-16 16:05:58 +0000[diff] [blame]1745<p><a href="mailto:stephane.bidoul@softwareag.com">Stéphane Bidoul</a>
Daniel Veillard7b4b2f92003-01-06 13:11:20 +0000[diff] [blame]1746maintains <a href="http://users.skynet.be/sbi/libxml-python/">a Windows port
1747of the Python bindings</a>.</p>
Daniel Veillardaf43f632002-03-08 15:05:20 +0000[diff] [blame]1748
Daniel Veillard7ef0fcb2002-12-14 10:38:55 +0000[diff] [blame]1749<p>Note to people interested in building bindings, the API is formalized as
1750<a href="libxml2-api.xml">an XML API description file</a> which allows to
1751automate a large part of the Python bindings, this includes function
Daniel Veillard7b4b2f92003-01-06 13:11:20 +0000[diff] [blame]1752descriptions, enums, structures, typedefs, etc... The Python script used to
1753build the bindings is python/generator.py in the source distribution.</p>
Daniel Veillard7ef0fcb2002-12-14 10:38:55 +0000[diff] [blame]1754
Daniel Veillardaf43f632002-03-08 15:05:20 +0000[diff] [blame]1755<p>To install the Python bindings there are 2 options:</p>
Daniel Veillard0b79dfe2002-02-23 13:02:31 +0000[diff] [blame]1756<ul>
Daniel Veillardaf43f632002-03-08 15:05:20 +0000[diff] [blame]1757 <li>If you use an RPM based distribution, simply install the <a
1758 href="http://rpmfind.net/linux/rpm2html/search.php?query=libxml2-python">libxml2-python
1759 RPM</a> (and if needed the <a
1760 href="http://rpmfind.net/linux/rpm2html/search.php?query=libxslt-python">libxslt-python
1761 RPM</a>).</li>
1762 <li>Otherwise use the <a href="ftp://xmlsoft.org/python/">libxml2-python
1763 module distribution</a> corresponding to your installed version of
1764 libxml2 and libxslt. Note that to install it you will need both libxml2
1765 and libxslt installed and run "python setup.py build install" in the
1766 module tree.</li>
Daniel Veillard0b79dfe2002-02-23 13:02:31 +0000[diff] [blame]1767</ul>
Daniel Veillardaf43f632002-03-08 15:05:20 +0000[diff] [blame]1768
1769<p>The distribution includes a set of examples and regression tests for the
1770python bindings in the <code>python/tests</code> directory. Here are some
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]1771excerpts from those tests:</p>
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]1772
1773<h3>tst.py:</h3>
1774
1775<p>This is a basic test of the file interface and DOM navigation:</p>
1776<pre>import libxml2
1777
1778doc = libxml2.parseFile("tst.xml")
1779if doc.name != "tst.xml":
1780 print "doc.name failed"
1781 sys.exit(1)
1782root = doc.children
1783if root.name != "doc":
1784 print "root.name failed"
1785 sys.exit(1)
1786child = root.children
1787if child.name != "foo":
1788 print "child.name failed"
1789 sys.exit(1)
1790doc.freeDoc()</pre>
1791
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]1792<p>The Python module is called libxml2; parseFile is the equivalent of
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]1793xmlParseFile (most of the bindings are automatically generated, and the xml
1794prefix is removed and the casing convention are kept). All node seen at the
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]1795binding level share the same subset of accessors:</p>
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]1796<ul>
Daniel Veillardaf43f632002-03-08 15:05:20 +0000[diff] [blame]1797 <li><code>name</code> : returns the node name</li>
Daniel Veillardc0801af2002-05-28 16:28:42 +0000[diff] [blame]1798 <li><code>type</code> : returns a string indicating the node type</li>
Daniel Veillardaf43f632002-03-08 15:05:20 +0000[diff] [blame]1799 <li><code>content</code> : returns the content of the node, it is based on
1800 xmlNodeGetContent() and hence is recursive.</li>
1801 <li><code>parent</code> , <code>children</code>, <code>last</code>,
1802 <code>next</code>, <code>prev</code>, <code>doc</code>,
1803 <code>properties</code>: pointing to the associated element in the tree,
1804 those may return None in case no such link exists.</li>
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]1805</ul>
1806
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]1807<p>Also note the need to explicitly deallocate documents with freeDoc() .
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]1808Reference counting for libxml2 trees would need quite a lot of work to
1809function properly, and rather than risk memory leaks if not implemented
1810correctly it sounds safer to have an explicit function to free a tree. The
1811wrapper python objects like doc, root or child are them automatically garbage
1812collected.</p>
1813
1814<h3>validate.py:</h3>
1815
1816<p>This test check the validation interfaces and redirection of error
1817messages:</p>
1818<pre>import libxml2
1819
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]1820#deactivate error messages from the validation
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]1821def noerr(ctx, str):
1822 pass
1823
1824libxml2.registerErrorHandler(noerr, None)
1825
1826ctxt = libxml2.createFileParserCtxt("invalid.xml")
1827ctxt.validate(1)
1828ctxt.parseDocument()
1829doc = ctxt.doc()
1830valid = ctxt.isValid()
1831doc.freeDoc()
1832if valid != 0:
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]1833 print "validity check failed"</pre>
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]1834
1835<p>The first thing to notice is the call to registerErrorHandler(), it
1836defines a new error handler global to the library. It is used to avoid seeing
1837the error messages when trying to validate the invalid document.</p>
1838
1839<p>The main interest of that test is the creation of a parser context with
1840createFileParserCtxt() and how the behaviour can be changed before calling
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]1841parseDocument() . Similarly the informations resulting from the parsing phase
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]1842are also available using context methods.</p>
1843
1844<p>Contexts like nodes are defined as class and the libxml2 wrappers maps the
1845C function interfaces in terms of objects method as much as possible. The
1846best to get a complete view of what methods are supported is to look at the
1847libxml2.py module containing all the wrappers.</p>
1848
1849<h3>push.py:</h3>
1850
1851<p>This test show how to activate the push parser interface:</p>
1852<pre>import libxml2
1853
1854ctxt = libxml2.createPushParser(None, "&lt;foo", 4, "test.xml")
1855ctxt.parseChunk("/&gt;", 2, 1)
1856doc = ctxt.doc()
1857
1858doc.freeDoc()</pre>
1859
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]1860<p>The context is created with a special call based on the
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]1861xmlCreatePushParser() from the C library. The first argument is an optional
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]1862SAX callback object, then the initial set of data, the length and the name of
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]1863the resource in case URI-References need to be computed by the parser.</p>
1864
1865<p>Then the data are pushed using the parseChunk() method, the last call
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]1866setting the third argument terminate to 1.</p>
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]1867
1868<h3>pushSAX.py:</h3>
1869
1870<p>this test show the use of the event based parsing interfaces. In this case
1871the parser does not build a document, but provides callback information as
1872the parser makes progresses analyzing the data being provided:</p>
1873<pre>import libxml2
1874log = ""
1875
1876class callback:
1877 def startDocument(self):
1878 global log
1879 log = log + "startDocument:"
1880
1881 def endDocument(self):
1882 global log
1883 log = log + "endDocument:"
1884
1885 def startElement(self, tag, attrs):
1886 global log
1887 log = log + "startElement %s %s:" % (tag, attrs)
1888
1889 def endElement(self, tag):
1890 global log
1891 log = log + "endElement %s:" % (tag)
1892
1893 def characters(self, data):
1894 global log
1895 log = log + "characters: %s:" % (data)
1896
1897 def warning(self, msg):
1898 global log
1899 log = log + "warning: %s:" % (msg)
1900
1901 def error(self, msg):
1902 global log
1903 log = log + "error: %s:" % (msg)
1904
1905 def fatalError(self, msg):
1906 global log
1907 log = log + "fatalError: %s:" % (msg)
1908
1909handler = callback()
1910
1911ctxt = libxml2.createPushParser(handler, "&lt;foo", 4, "test.xml")
1912chunk = " url='tst'&gt;b"
1913ctxt.parseChunk(chunk, len(chunk), 0)
1914chunk = "ar&lt;/foo&gt;"
1915ctxt.parseChunk(chunk, len(chunk), 1)
1916
Daniel Veillardfcbfa2d2002-02-21 17:54:27 +0000[diff] [blame]1917reference = "startDocument:startElement foo {'url': 'tst'}:" + \
1918 "characters: bar:endElement foo:endDocument:"
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]1919if log != reference:
1920 print "Error got: %s" % log
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]1921 print "Expected: %s" % reference</pre>
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]1922
1923<p>The key object in that test is the handler, it provides a number of entry
1924points which can be called by the parser as it makes progresses to indicate
1925the information set obtained. The full set of callback is larger than what
1926the callback class in that specific example implements (see the SAX
1927definition for a complete list). The wrapper will only call those supplied by
1928the object when activated. The startElement receives the names of the element
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]1929and a dictionary containing the attributes carried by this element.</p>
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]1930
1931<p>Also note that the reference string generated from the callback shows a
1932single character call even though the string "bar" is passed to the parser
1933from 2 different call to parseChunk()</p>
1934
1935<h3>xpath.py:</h3>
1936
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]1937<p>This is a basic test of XPath wrappers support</p>
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]1938<pre>import libxml2
1939
1940doc = libxml2.parseFile("tst.xml")
1941ctxt = doc.xpathNewContext()
1942res = ctxt.xpathEval("//*")
1943if len(res) != 2:
1944 print "xpath query: wrong node set size"
1945 sys.exit(1)
1946if res[0].name != "doc" or res[1].name != "foo":
1947 print "xpath query: wrong node set value"
1948 sys.exit(1)
1949doc.freeDoc()
1950ctxt.xpathFreeContext()</pre>
1951
1952<p>This test parses a file, then create an XPath context to evaluate XPath
1953expression on it. The xpathEval() method execute an XPath query and returns
1954the result mapped in a Python way. String and numbers are natively converted,
1955and node sets are returned as a tuple of libxml2 Python nodes wrappers. Like
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]1956the document, the XPath context need to be freed explicitly, also not that
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]1957the result of the XPath query may point back to the document tree and hence
1958the document must be freed after the result of the query is used.</p>
1959
1960<h3>xpathext.py:</h3>
1961
1962<p>This test shows how to extend the XPath engine with functions written in
1963python:</p>
1964<pre>import libxml2
1965
1966def foo(ctx, x):
1967 return x + 1
1968
1969doc = libxml2.parseFile("tst.xml")
1970ctxt = doc.xpathNewContext()
1971libxml2.registerXPathFunction(ctxt._o, "foo", None, foo)
1972res = ctxt.xpathEval("foo(1)")
1973if res != 2:
1974 print "xpath extension failure"
1975doc.freeDoc()
1976ctxt.xpathFreeContext()</pre>
1977
1978<p>Note how the extension function is registered with the context (but that
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]1979part is not yet finalized, this may change slightly in the future).</p>
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]1980
1981<h3>tstxpath.py:</h3>
1982
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]1983<p>This test is similar to the previous one but shows how the extension
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]1984function can access the XPath evaluation context:</p>
1985<pre>def foo(ctx, x):
1986 global called
1987
1988 #
1989 # test that access to the XPath evaluation contexts
1990 #
1991 pctxt = libxml2.xpathParserContext(_obj=ctx)
1992 ctxt = pctxt.context()
1993 called = ctxt.function()
1994 return x + 1</pre>
1995
1996<p>All the interfaces around the XPath parser(or rather evaluation) context
1997are not finalized, but it should be sufficient to do contextual work at the
1998evaluation point.</p>
1999
2000<h3>Memory debugging:</h3>
2001
2002<p>last but not least, all tests starts with the following prologue:</p>
2003<pre>#memory debug specific
Daniel Veillardaf43f632002-03-08 15:05:20 +0000[diff] [blame]2004libxml2.debugMemory(1)</pre>
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]2005
2006<p>and ends with the following epilogue:</p>
2007<pre>#memory debug specific
2008libxml2.cleanupParser()
2009if libxml2.debugMemory(1) == 0:
2010 print "OK"
2011else:
2012 print "Memory leak %d bytes" % (libxml2.debugMemory(1))
2013 libxml2.dumpMemory()</pre>
2014
2015<p>Those activate the memory debugging interface of libxml2 where all
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]2016allocated block in the library are tracked. The prologue then cleans up the
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]2017library state and checks that all allocated memory has been freed. If not it
2018calls dumpMemory() which saves that list in a <code>.memdump</code> file.</p>
Daniel Veillard82687162001-01-22 15:32:01 +0000[diff] [blame]2019
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]2020<h2><a name="architecture">libxml2 architecture</a></h2>
Daniel Veillard4540be42000-08-19 16:40:28 +0000[diff] [blame]2021
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]2022<p>Libxml2 is made of multiple components; some of them are optional, and most
Daniel Veillardec70e912001-02-26 20:10:45 +0000[diff] [blame]2023of the block interfaces are public. The main components are:</p>
Daniel Veillard4540be42000-08-19 16:40:28 +0000[diff] [blame]2024<ul>
2025 <li>an Input/Output layer</li>
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]2026 <li>FTP and HTTP client layers (optional)</li>
Daniel Veillard4540be42000-08-19 16:40:28 +0000[diff] [blame]2027 <li>an Internationalization layer managing the encodings support</li>
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]2028 <li>a URI module</li>
Daniel Veillard4540be42000-08-19 16:40:28 +0000[diff] [blame]2029 <li>the XML parser and its basic SAX interface</li>
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]2030 <li>an HTML parser using the same SAX interface (optional)</li>
Daniel Veillard4540be42000-08-19 16:40:28 +0000[diff] [blame]2031 <li>a SAX tree module to build an in-memory DOM representation</li>
2032 <li>a tree module to manipulate the DOM representation</li>
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]2033 <li>a validation module using the DOM representation (optional)</li>
Daniel Veillard4540be42000-08-19 16:40:28 +0000[diff] [blame]2034 <li>an XPath module for global lookup in a DOM representation
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]2035 (optional)</li>
2036 <li>a debug module (optional)</li>
Daniel Veillard4540be42000-08-19 16:40:28 +0000[diff] [blame]2037</ul>
2038
2039<p>Graphically this gives the following:</p>
2040
2041<p><img src="libxml.gif" alt="a graphical view of the various"></p>
2042
2043<p></p>
2044
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]2045<h2><a name="tree">The tree output</a></h2>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]2046
2047<p>The parser returns a tree built during the document analysis. The value
Daniel Veillard402e8c82000-02-29 22:57:47 +0000[diff] [blame]2048returned is an <strong>xmlDocPtr</strong> (i.e., a pointer to an
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]2049<strong>xmlDoc</strong> structure). This structure contains information such
Daniel Veillard306be992000-07-03 12:38:45 +0000[diff] [blame]2050as the file name, the document type, and a <strong>children</strong> pointer
2051which is the root of the document (or more exactly the first child under the
2052root which is the document). The tree is made of <strong>xmlNode</strong>s,
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]2053chained in double-linked lists of siblings and with a children&lt;-&gt;parent
Daniel Veillard306be992000-07-03 12:38:45 +0000[diff] [blame]2054relationship. An xmlNode can also carry properties (a chain of xmlAttr
2055structures). An attribute may have a value which is a list of TEXT or
2056ENTITY_REF nodes.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]2057
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]2058<p>Here is an example (erroneous with respect to the XML spec since there
2059should be only one ELEMENT under the root):</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]2060
2061<p><img src="structure.gif" alt=" structure.gif "></p>
2062
2063<p>In the source package there is a small program (not installed by default)
Daniel Veillard361d8452000-04-03 19:48:13 +0000[diff] [blame]2064called <strong>xmllint</strong> which parses XML files given as argument and
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]2065prints them back as parsed. This is useful for detecting errors both in XML
2066code and in the XML parser itself. It has an option <strong>--debug</strong>
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]2067which prints the actual in-memory structure of the document; here is the
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]2068result with the <a href="#example">example</a> given before:</p>
Daniel Veillard10c6a8f1998-10-28 01:00:12 +0000[diff] [blame]2069<pre>DOCUMENT
2070version=1.0
2071standalone=true
2072 ELEMENT EXAMPLE
2073 ATTRIBUTE prop1
2074 TEXT
2075 content=gnome is great
2076 ATTRIBUTE prop2
2077 ENTITY_REF
2078 TEXT
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]2079 content= linux too
Daniel Veillard402e8c82000-02-29 22:57:47 +0000[diff] [blame]2080 ELEMENT head
Daniel Veillard10c6a8f1998-10-28 01:00:12 +0000[diff] [blame]2081 ELEMENT title
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]2082 TEXT
2083 content=Welcome to Gnome
Daniel Veillard10c6a8f1998-10-28 01:00:12 +0000[diff] [blame]2084 ELEMENT chapter
2085 ELEMENT title
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]2086 TEXT
2087 content=The Linux adventure
Daniel Veillard10c6a8f1998-10-28 01:00:12 +0000[diff] [blame]2088 ELEMENT p
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]2089 TEXT
2090 content=bla bla bla ...
Daniel Veillard10c6a8f1998-10-28 01:00:12 +0000[diff] [blame]2091 ELEMENT image
2092 ATTRIBUTE href
2093 TEXT
2094 content=linus.gif
2095 ELEMENT p
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]2096 TEXT
2097 content=...</pre>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]2098
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]2099<p>This should be useful for learning the internal representation model.</p>
Daniel Veillardccb09631998-10-27 06:21:04 +0000[diff] [blame]2100
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]2101<h2><a name="interface">The SAX interface</a></h2>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]2102
Daniel Veillard402e8c82000-02-29 22:57:47 +0000[diff] [blame]2103<p>Sometimes the DOM tree output is just too large to fit reasonably into
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]2104memory. 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]2105loaded using libxml), it's better to use the SAX interface of libxml. SAX is
2106a <strong>callback-based interface</strong> to the parser. Before parsing,
2107the application layer registers a customized set of callbacks which are
2108called by the library as it progresses through the XML input.</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]2109
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]2110<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]2111libxml, see the <a
2112href="http://www.daa.com.au/~james/gnome/xml-sax/xml-sax.html">nice
2113documentation</a>.written by <a href="mailto:james@daa.com.au">James
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]2114Henstridge</a>.</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]2115
2116<p>You can debug the SAX behaviour by using the <strong>testSAX</strong>
2117program located in the gnome-xml module (it's usually not shipped in the
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]2118binary packages of libxml, but you can find it in the tar source
Daniel Veillard402e8c82000-02-29 22:57:47 +0000[diff] [blame]2119distribution). Here is the sequence of callbacks that would be reported by
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]2120testSAX when parsing the example XML document shown earlier:</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]2121<pre>SAX.setDocumentLocator()
2122SAX.startDocument()
2123SAX.getEntity(amp)
2124SAX.startElement(EXAMPLE, prop1='gnome is great', prop2='&amp;amp; linux too')
2125SAX.characters( , 3)
2126SAX.startElement(head)
2127SAX.characters( , 4)
2128SAX.startElement(title)
2129SAX.characters(Welcome to Gnome, 16)
2130SAX.endElement(title)
2131SAX.characters( , 3)
2132SAX.endElement(head)
2133SAX.characters( , 3)
2134SAX.startElement(chapter)
2135SAX.characters( , 4)
2136SAX.startElement(title)
2137SAX.characters(The Linux adventure, 19)
2138SAX.endElement(title)
2139SAX.characters( , 4)
2140SAX.startElement(p)
2141SAX.characters(bla bla bla ..., 15)
2142SAX.endElement(p)
2143SAX.characters( , 4)
2144SAX.startElement(image, href='linus.gif')
2145SAX.endElement(image)
2146SAX.characters( , 4)
2147SAX.startElement(p)
2148SAX.characters(..., 3)
2149SAX.endElement(p)
2150SAX.characters( , 3)
2151SAX.endElement(chapter)
2152SAX.characters( , 1)
2153SAX.endElement(EXAMPLE)
2154SAX.endDocument()</pre>
2155
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]2156<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]2157facility, so nearly everything up to the end of this document presupposes the
2158use of the standard DOM tree build. Note that the DOM tree itself is built by
2159a set of registered default callbacks, without internal specific
2160interface.</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]2161
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2162<h2><a name="Validation">Validation &amp; DTDs</a></h2>
2163
2164<p>Table of Content:</p>
2165<ol>
2166 <li><a href="#General5">General overview</a></li>
2167 <li><a href="#definition">The definition</a></li>
2168 <li><a href="#Simple">Simple rules</a>
2169 <ol>
Daniel Veillard9c466822001-10-25 12:03:39 +0000[diff] [blame]2170 <li><a href="#reference">How to reference a DTD from a document</a></li>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2171 <li><a href="#Declaring">Declaring elements</a></li>
2172 <li><a href="#Declaring1">Declaring attributes</a></li>
2173 </ol>
2174 </li>
2175 <li><a href="#Some">Some examples</a></li>
2176 <li><a href="#validate">How to validate</a></li>
2177 <li><a href="#Other">Other resources</a></li>
2178</ol>
2179
2180<h3><a name="General5">General overview</a></h3>
2181
2182<p>Well what is validation and what is a DTD ?</p>
2183
2184<p>DTD is the acronym for Document Type Definition. This is a description of
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]2185the 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]2186specification, and allows one to describe and verify that a given document
2187instance conforms to the set of rules detailing its structure and content.</p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2188
2189<p>Validation is the process of checking a document against a DTD (more
2190generally against a set of construction rules).</p>
2191
2192<p>The validation process and building DTDs are the two most difficult parts
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]2193of the XML life cycle. Briefly a DTD defines all the possible elements to be
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2194found within your document, what is the formal shape of your document tree
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]2195(by defining the allowed content of an element; either text, a regular
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2196expression for the allowed list of children, or mixed content i.e. both text
Daniel Veillard42766c02002-08-22 20:52:17 +0000[diff] [blame]2197and children). The DTD also defines the valid attributes for all elements and
2198the types of those attributes.</p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2199
2200<h3><a name="definition1">The definition</a></h3>
2201
2202<p>The <a href="http://www.w3.org/TR/REC-xml">W3C XML Recommendation</a> (<a
2203href="http://www.xml.com/axml/axml.html">Tim Bray's annotated version of
2204Rev1</a>):</p>
2205<ul>
2206 <li><a href="http://www.w3.org/TR/REC-xml#elemdecls">Declaring
2207 elements</a></li>
2208 <li><a href="http://www.w3.org/TR/REC-xml#attdecls">Declaring
2209 attributes</a></li>
2210</ul>
2211
2212<p>(unfortunately) all this is inherited from the SGML world, the syntax is
2213ancient...</p>
2214
2215<h3><a name="Simple1">Simple rules</a></h3>
2216
Daniel Veillard42766c02002-08-22 20:52:17 +0000[diff] [blame]2217<p>Writing DTDs can be done in many ways. The rules to build them if you need
2218something permanent or something which can evolve over time can be radically
2219different. Really complex DTDs like DocBook ones are flexible but quite
2220harder 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]2221structure. It is just a set of basic rules, and definitely not exhaustive nor
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]2222usable for complex DTD design.</p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2223
2224<h4><a name="reference1">How to reference a DTD from a document</a>:</h4>
2225
2226<p>Assuming the top element of the document is <code>spec</code> and the dtd
2227is placed in the file <code>mydtd</code> in the subdirectory
2228<code>dtds</code> of the directory from where the document were loaded:</p>
2229
2230<p><code>&lt;!DOCTYPE spec SYSTEM "dtds/mydtd"&gt;</code></p>
2231
2232<p>Notes:</p>
2233<ul>
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]2234 <li>The system string is actually an URI-Reference (as defined in <a
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2235 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]2236 full URL string indicating the location of your DTD on the Web. This is a
2237 really good thing to do if you want others to validate your document.</li>
2238 <li>It is also possible to associate a <code>PUBLIC</code> identifier (a
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]2239 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]2240 without having to locate it on the web.</li>
2241 <li>A DTD contains a set of element and attribute declarations, but they
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]2242 don't define what the root of the document should be. This is explicitly
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2243 told to the parser/validator as the first element of the
2244 <code>DOCTYPE</code> declaration.</li>
2245</ul>
2246
2247<h4><a name="Declaring2">Declaring elements</a>:</h4>
2248
2249<p>The following declares an element <code>spec</code>:</p>
2250
2251<p><code>&lt;!ELEMENT spec (front, body, back?)&gt;</code></p>
2252
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]2253<p>It also expresses that the spec element contains one <code>front</code>,
Daniel Veillardc0801af2002-05-28 16:28:42 +0000[diff] [blame]2254one <code>body</code> and one optional <code>back</code> children elements in
2255this order. The declaration of one element of the structure and its content
2256are done in a single declaration. Similarly the following declares
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2257<code>div1</code> elements:</p>
2258
Daniel Veillard51737272002-01-23 23:10:38 +0000[diff] [blame]2259<p><code>&lt;!ELEMENT div1 (head, (p | list | note)*, div2?)&gt;</code></p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2260
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]2261<p>which means div1 contains one <code>head</code> then a series of optional
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2262<code>p</code>, <code>list</code>s and <code>note</code>s and then an
2263optional <code>div2</code>. And last but not least an element can contain
2264text:</p>
2265
2266<p><code>&lt;!ELEMENT b (#PCDATA)&gt;</code></p>
2267
2268<p><code>b</code> contains text or being of mixed content (text and elements
2269in no particular order):</p>
2270
2271<p><code>&lt;!ELEMENT p (#PCDATA|a|ul|b|i|em)*&gt;</code></p>
2272
2273<p><code>p </code>can contain text or <code>a</code>, <code>ul</code>,
2274<code>b</code>, <code>i </code>or <code>em</code> elements in no particular
2275order.</p>
2276
2277<h4><a name="Declaring1">Declaring attributes</a>:</h4>
2278
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]2279<p>Again the attributes declaration includes their content definition:</p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2280
2281<p><code>&lt;!ATTLIST termdef name CDATA #IMPLIED&gt;</code></p>
2282
2283<p>means that the element <code>termdef</code> can have a <code>name</code>
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]2284attribute containing text (<code>CDATA</code>) and which is optional
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2285(<code>#IMPLIED</code>). The attribute value can also be defined within a
2286set:</p>
2287
2288<p><code>&lt;!ATTLIST list type (bullets|ordered|glossary)
2289"ordered"&gt;</code></p>
2290
2291<p>means <code>list</code> element have a <code>type</code> attribute with 3
2292allowed values "bullets", "ordered" or "glossary" and which default to
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]2293"ordered" if the attribute is not explicitly specified.</p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2294
2295<p>The content type of an attribute can be text (<code>CDATA</code>),
2296anchor/reference/references
2297(<code>ID</code>/<code>IDREF</code>/<code>IDREFS</code>), entity(ies)
2298(<code>ENTITY</code>/<code>ENTITIES</code>) or name(s)
2299(<code>NMTOKEN</code>/<code>NMTOKENS</code>). The following defines that a
2300<code>chapter</code> element can have an optional <code>id</code> attribute
2301of type <code>ID</code>, usable for reference from attribute of type
2302IDREF:</p>
2303
2304<p><code>&lt;!ATTLIST chapter id ID #IMPLIED&gt;</code></p>
2305
2306<p>The last value of an attribute definition can be <code>#REQUIRED
2307</code>meaning that the attribute has to be given, <code>#IMPLIED</code>
2308meaning that it is optional, or the default value (possibly prefixed by
2309<code>#FIXED</code> if it is the only allowed).</p>
2310
2311<p>Notes:</p>
2312<ul>
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]2313 <li>Usually the attributes pertaining to a given element are declared in a
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2314 single expression, but it is just a convention adopted by a lot of DTD
2315 writers:
2316 <pre>&lt;!ATTLIST termdef
2317 id ID #REQUIRED
2318 name CDATA #IMPLIED&gt;</pre>
2319 <p>The previous construct defines both <code>id</code> and
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]2320 <code>name</code> attributes for the element <code>termdef</code>.</p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2321 </li>
2322</ul>
2323
2324<h3><a name="Some1">Some examples</a></h3>
2325
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]2326<p>The directory <code>test/valid/dtds/</code> in the libxml2 distribution
Daniel Veillard42766c02002-08-22 20:52:17 +0000[diff] [blame]2327contains some complex DTD examples. The example in the file
2328<code>test/valid/dia.xml</code> shows an XML file where the simple DTD is
2329directly included within the document.</p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2330
2331<h3><a name="validate1">How to validate</a></h3>
2332
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]2333<p>The simplest way is to use the xmllint program included with libxml. The
2334<code>--valid</code> option turns-on validation of the files given as input.
2335For example the following validates a copy of the first revision of the XML
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]23361.0 specification:</p>
2337
2338<p><code>xmllint --valid --noout test/valid/REC-xml-19980210.xml</code></p>
2339
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]2340<p>the -- noout is used to disable output of the resulting tree.</p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2341
Daniel Veillard42766c02002-08-22 20:52:17 +0000[diff] [blame]2342<p>The <code>--dtdvalid dtd</code> allows validation of the document(s)
2343against a given DTD.</p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2344
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]2345<p>Libxml2 exports an API to handle DTDs and validation, check the <a
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2346href="http://xmlsoft.org/html/libxml-valid.html">associated
2347description</a>.</p>
2348
2349<h3><a name="Other1">Other resources</a></h3>
2350
2351<p>DTDs are as old as SGML. So there may be a number of examples on-line, I
2352will just list one for now, others pointers welcome:</p>
2353<ul>
2354 <li><a href="http://www.xml101.com:8081/dtd/">XML-101 DTD</a></li>
2355</ul>
2356
2357<p>I suggest looking at the examples found under test/valid/dtd and any of
2358the large number of books available on XML. The dia example in test/valid
2359should be both simple and complete enough to allow you to build your own.</p>
2360
2361<p></p>
2362
2363<h2><a name="Memory">Memory Management</a></h2>
2364
2365<p>Table of Content:</p>
2366<ol>
2367 <li><a href="#General3">General overview</a></li>
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]2368 <li><a href="#setting">Setting libxml2 set of memory routines</a></li>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2369 <li><a href="#cleanup">Cleaning up after parsing</a></li>
2370 <li><a href="#Debugging">Debugging routines</a></li>
2371 <li><a href="#General4">General memory requirements</a></li>
2372</ol>
2373
2374<h3><a name="General3">General overview</a></h3>
2375
2376<p>The module <code><a
2377href="http://xmlsoft.org/html/libxml-xmlmemory.html">xmlmemory.h</a></code>
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]2378provides the interfaces to the libxml2 memory system:</p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2379<ul>
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]2380 <li>libxml2 does not use the libc memory allocator directly but xmlFree(),
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2381 xmlMalloc() and xmlRealloc()</li>
2382 <li>those routines can be reallocated to a specific set of routine, by
2383 default the libc ones i.e. free(), malloc() and realloc()</li>
2384 <li>the xmlmemory.c module includes a set of debugging routine</li>
2385</ul>
2386
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]2387<h3><a name="setting">Setting libxml2 set of memory routines</a></h3>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2388
2389<p>It is sometimes useful to not use the default memory allocator, either for
2390debugging, analysis or to implement a specific behaviour on memory management
2391(like on embedded systems). Two function calls are available to do so:</p>
2392<ul>
Daniel Veillardaf43f632002-03-08 15:05:20 +0000[diff] [blame]2393 <li><a href="http://xmlsoft.org/html/libxml-xmlmemory.html">xmlMemGet
2394 ()</a> which return the current set of functions in use by the parser</li>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2395 <li><a
2396 href="http://xmlsoft.org/html/libxml-xmlmemory.html">xmlMemSetup()</a>
Daniel Veillardaf43f632002-03-08 15:05:20 +0000[diff] [blame]2397 which allow to set up a new set of memory allocation functions</li>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2398</ul>
2399
2400<p>Of course a call to xmlMemSetup() should probably be done before calling
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]2401any other libxml2 routines (unless you are sure your allocations routines are
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2402compatibles).</p>
2403
2404<h3><a name="cleanup">Cleaning up after parsing</a></h3>
2405
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]2406<p>Libxml2 is not stateless, there is a few set of memory structures needing
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]2407allocation before the parser is fully functional (some encoding structures
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2408for example). This also mean that once parsing is finished there is a tiny
2409amount of memory (a few hundred bytes) which can be recollected if you don't
2410reuse the parser immediately:</p>
2411<ul>
2412 <li><a href="http://xmlsoft.org/html/libxml-parser.html">xmlCleanupParser
Daniel Veillardaf43f632002-03-08 15:05:20 +0000[diff] [blame]2413 ()</a> is a centralized routine to free the parsing states. Note that it
2414 won't deallocate any produced tree if any (use the xmlFreeDoc() and
2415 related routines for this).</li>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2416 <li><a href="http://xmlsoft.org/html/libxml-parser.html">xmlInitParser
Daniel Veillardaf43f632002-03-08 15:05:20 +0000[diff] [blame]2417 ()</a> is the dual routine allowing to preallocate the parsing state
2418 which can be useful for example to avoid initialization reentrancy
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]2419 problems when using libxml2 in multithreaded applications</li>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2420</ul>
2421
2422<p>Generally xmlCleanupParser() is safe, if needed the state will be rebuild
2423at the next invocation of parser routines, but be careful of the consequences
2424in multithreaded applications.</p>
2425
2426<h3><a name="Debugging">Debugging routines</a></h3>
2427
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]2428<p>When configured using --with-mem-debug flag (off by default), libxml2 uses
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]2429a set of memory allocation debugging routines keeping track of all allocated
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2430blocks and the location in the code where the routine was called. A couple of
2431other debugging routines allow to dump the memory allocated infos to a file
2432or call a specific routine when a given block number is allocated:</p>
2433<ul>
2434 <li><a
2435 href="http://xmlsoft.org/html/libxml-xmlmemory.html">xmlMallocLoc()</a>
Daniel Veillardaf43f632002-03-08 15:05:20 +0000[diff] [blame]2436 <a
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2437 href="http://xmlsoft.org/html/libxml-xmlmemory.html">xmlReallocLoc()</a>
2438 and <a
2439 href="http://xmlsoft.org/html/libxml-xmlmemory.html">xmlMemStrdupLoc()</a>
2440 are the memory debugging replacement allocation routines</li>
2441 <li><a href="http://xmlsoft.org/html/libxml-xmlmemory.html">xmlMemoryDump
Daniel Veillardaf43f632002-03-08 15:05:20 +0000[diff] [blame]2442 ()</a> dumps all the informations about the allocated memory block lefts
2443 in the <code>.memdump</code> file</li>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2444</ul>
2445
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]2446<p>When developing libxml2 memory debug is enabled, the tests programs call
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2447xmlMemoryDump () and the "make test" regression tests will check for any
2448memory leak during the full regression test sequence, this helps a lot
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]2449ensuring that libxml2 does not leak memory and bullet proof memory
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2450allocations use (some libc implementations are known to be far too permissive
2451resulting in major portability problems!).</p>
2452
2453<p>If the .memdump reports a leak, it displays the allocation function and
2454also tries to give some informations about the content and structure of the
2455allocated blocks left. This is sufficient in most cases to find the culprit,
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]2456but not always. Assuming the allocation problem is reproducible, it is
2457possible to find more easily:</p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2458<ol>
2459 <li>write down the block number xxxx not allocated</li>
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]2460 <li>export the environment variable XML_MEM_BREAKPOINT=xxxx , the easiest
Daniel Veillard75794822002-04-11 16:24:32 +0000[diff] [blame]2461 when using GDB is to simply give the command
2462 <p><code>set environment XML_MEM_BREAKPOINT xxxx</code></p>
2463 <p>before running the program.</p>
2464 </li>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2465 <li>run the program under a debugger and set a breakpoint on
2466 xmlMallocBreakpoint() a specific function called when this precise block
2467 is allocated</li>
2468 <li>when the breakpoint is reached you can then do a fine analysis of the
2469 allocation an step to see the condition resulting in the missing
2470 deallocation.</li>
2471</ol>
2472
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]2473<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]2474noticing that it was not detecting memory leaks that simple mechanism was
Daniel Veillard75794822002-04-11 16:24:32 +0000[diff] [blame]2475used and proved extremely efficient until now. Lately I have also used <a
2476href="http://developer.kde.org/~sewardj/">valgrind</a> with quite some
2477success, it is tied to the i386 architecture since it works by emulating the
2478processor and instruction set, it is slow but extremely efficient, i.e. it
2479spot memory usage errors in a very precise way.</p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2480
2481<h3><a name="General4">General memory requirements</a></h3>
2482
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]2483<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]2484of a number of things:</p>
2485<ul>
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]2486 <li>the parser itself should work in a fixed amount of memory, except for
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2487 information maintained about the stacks of names and entities locations.
2488 The I/O and encoding handlers will probably account for a few KBytes.
2489 This is true for both the XML and HTML parser (though the HTML parser
2490 need more state).</li>
2491 <li>If you are generating the DOM tree then memory requirements will grow
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]2492 nearly linear with the size of the data. In general for a balanced
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2493 textual document the internal memory requirement is about 4 times the
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]2494 size of the UTF8 serialization of this document (example the XML-1.0
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2495 recommendation is a bit more of 150KBytes and takes 650KBytes of main
2496 memory when parsed). Validation will add a amount of memory required for
2497 maintaining the external Dtd state which should be linear with the
2498 complexity of the content model defined by the Dtd</li>
Daniel Veillardce192eb2003-04-16 15:58:05 +0000[diff] [blame]2499 <li>If you need to work with fixed memory requirements or don't need the
2500 full DOM tree then using the <a href="xmlreader.html">xmlReader
2501 interface</a> is probably the best way to proceed, it still allows to
2502 validate or operate on subset of the tree if needed.</li>
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]2503 <li>If you don't care about the advanced features of libxml2 like
Daniel Veillardce192eb2003-04-16 15:58:05 +0000[diff] [blame]2504 validation, DOM, XPath or XPointer, don't use entities, need to work with
2505 fixed memory requirements, and try to get the fastest parsing possible
2506 then the SAX interface should be used, but it has known restrictions.</li>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2507</ul>
2508
2509<p></p>
2510
2511<h2><a name="Encodings">Encodings support</a></h2>
2512
2513<p>Table of Content:</p>
2514<ol>
2515 <li><a href="encoding.html#What">What does internationalization support
2516 mean ?</a></li>
2517 <li><a href="encoding.html#internal">The internal encoding, how and
2518 why</a></li>
2519 <li><a href="encoding.html#implemente">How is it implemented ?</a></li>
2520 <li><a href="encoding.html#Default">Default supported encodings</a></li>
2521 <li><a href="encoding.html#extend">How to extend the existing
2522 support</a></li>
2523</ol>
2524
2525<h3><a name="What">What does internationalization support mean ?</a></h3>
2526
Daniel Veillard238836e2003-04-07 22:57:29 +0000[diff] [blame]2527<p>If you are not really familiar with Internationalization (usual shorcut is
2528I18N) , Unicode, characters and glyphs, I suggest you read a <a
2529href="http://www.tbray.org/ongoing/When/200x/2003/04/06/Unicode">presentation</a>
2530by Tim Bray on Unicode and why you should care about it.</p>
2531
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2532<p>XML was designed from the start to allow the support of any character set
2533by using Unicode. Any conformant XML parser has to support the UTF-8 and
2534UTF-16 default encodings which can both express the full unicode ranges. UTF8
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]2535is a variable length encoding whose greatest points are to reuse the same
2536encoding for ASCII and to save space for Western encodings, but it is a bit
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2537more complex to handle in practice. UTF-16 use 2 bytes per characters (and
2538sometimes combines two pairs), it makes implementation easier, but looks a
2539bit overkill for Western languages encoding. Moreover the XML specification
2540allows document to be encoded in other encodings at the condition that they
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]2541are clearly labeled as such. For example the following is a wellformed XML
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2542document encoded in ISO-8859 1 and using accentuated letter that we French
2543likes for both markup and content:</p>
2544<pre>&lt;?xml version="1.0" encoding="ISO-8859-1"?&gt;
2545&lt;très&gt;là&lt;/très&gt;</pre>
2546
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]2547<p>Having internationalization support in libxml2 means the following:</p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2548<ul>
2549 <li>the document is properly parsed</li>
2550 <li>informations about it's encoding are saved</li>
2551 <li>it can be modified</li>
2552 <li>it can be saved in its original encoding</li>
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]2553 <li>it can also be saved in another encoding supported by libxml2 (for
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2554 example straight UTF8 or even an ASCII form)</li>
2555</ul>
2556
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]2557<p>Another very important point is that the whole libxml2 API, with the
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2558exception of a few routines to read with a specific encoding or save to a
2559specific encoding, is completely agnostic about the original encoding of the
2560document.</p>
2561
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]2562<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]2563the 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]2564an internationalized fashion by libxml2 too:</p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2565<pre>&lt;!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"
2566 "http://www.w3.org/TR/REC-html40/loose.dtd"&gt;
2567&lt;html lang="fr"&gt;
2568&lt;head&gt;
2569 &lt;META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=ISO-8859-1"&gt;
2570&lt;/head&gt;
2571&lt;body&gt;
2572&lt;p&gt;W3C crée des standards pour le Web.&lt;/body&gt;
2573&lt;/html&gt;</pre>
2574
2575<h3><a name="internal">The internal encoding, how and why</a></h3>
2576
2577<p>One of the core decision was to force all documents to be converted to a
2578default internal encoding, and that encoding to be UTF-8, here are the
2579rationale for those choices:</p>
2580<ul>
2581 <li>keeping the native encoding in the internal form would force the libxml
2582 users (or the code associated) to be fully aware of the encoding of the
2583 original document, for examples when adding a text node to a document,
2584 the content would have to be provided in the document encoding, i.e. the
2585 client code would have to check it before hand, make sure it's conformant
2586 to the encoding, etc ... Very hard in practice, though in some specific
2587 cases this may make sense.</li>
2588 <li>the second decision was which encoding. From the XML spec only UTF8 and
2589 UTF16 really makes sense as being the two only encodings for which there
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]2590 is mandatory support. UCS-4 (32 bits fixed size encoding) could be
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2591 considered an intelligent choice too since it's a direct Unicode mapping
2592 support. I selected UTF-8 on the basis of efficiency and compatibility
2593 with surrounding software:
2594 <ul>
2595 <li>UTF-8 while a bit more complex to convert from/to (i.e. slightly
2596 more costly to import and export CPU wise) is also far more compact
2597 than UTF-16 (and UCS-4) for a majority of the documents I see it used
2598 for right now (RPM RDF catalogs, advogato data, various configuration
2599 file formats, etc.) and the key point for today's computer
2600 architecture is efficient uses of caches. If one nearly double the
2601 memory requirement to store the same amount of data, this will trash
2602 caches (main memory/external caches/internal caches) and my take is
2603 that this harms the system far more than the CPU requirements needed
2604 for the conversion to UTF-8</li>
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]2605 <li>Most of libxml2 version 1 users were using it with straight ASCII
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2606 most of the time, doing the conversion with an internal encoding
2607 requiring all their code to be rewritten was a serious show-stopper
2608 for using UTF-16 or UCS-4.</li>
2609 <li>UTF-8 is being used as the de-facto internal encoding standard for
2610 related code like the <a href="http://www.pango.org/">pango</a>
2611 upcoming Gnome text widget, and a lot of Unix code (yep another place
2612 where Unix programmer base takes a different approach from Microsoft
2613 - they are using UTF-16)</li>
2614 </ul>
2615 </li>
2616</ul>
2617
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]2618<p>What does this mean in practice for the libxml2 user:</p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2619<ul>
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]2620 <li>xmlChar, the libxml2 data type is a byte, those bytes must be assembled
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2621 as UTF-8 valid strings. The proper way to terminate an xmlChar * string
2622 is simply to append 0 byte, as usual.</li>
2623 <li>One just need to make sure that when using chars outside the ASCII set,
2624 the values has been properly converted to UTF-8</li>
2625</ul>
2626
2627<h3><a name="implemente">How is it implemented ?</a></h3>
2628
2629<p>Let's describe how all this works within libxml, basically the I18N
2630(internationalization) support get triggered only during I/O operation, i.e.
2631when reading a document or saving one. Let's look first at the reading
2632sequence:</p>
2633<ol>
2634 <li>when a document is processed, we usually don't know the encoding, a
2635 simple heuristic allows to detect UTF-18 and UCS-4 from whose where the
2636 ASCII range (0-0x7F) maps with ASCII</li>
2637 <li>the xml declaration if available is parsed, including the encoding
2638 declaration. At that point, if the autodetected encoding is different
2639 from the one declared a call to xmlSwitchEncoding() is issued.</li>
2640 <li>If there is no encoding declaration, then the input has to be in either
2641 UTF-8 or UTF-16, if it is not then at some point when processing the
2642 input, the converter/checker of UTF-8 form will raise an encoding error.
2643 You may end-up with a garbled document, or no document at all ! Example:
2644 <pre>~/XML -&gt; ./xmllint err.xml
2645err.xml:1: error: Input is not proper UTF-8, indicate encoding !
2646&lt;très&gt;là&lt;/très&gt;
2647 ^
2648err.xml:1: error: Bytes: 0xE8 0x73 0x3E 0x6C
2649&lt;très&gt;là&lt;/très&gt;
2650 ^</pre>
2651 </li>
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]2652 <li>xmlSwitchEncoding() does an encoding name lookup, canonicalize it, and
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2653 then search the default registered encoding converters for that encoding.
2654 If it's not within the default set and iconv() support has been compiled
2655 it, it will ask iconv for such an encoder. If this fails then the parser
2656 will report an error and stops processing:
2657 <pre>~/XML -&gt; ./xmllint err2.xml
2658err2.xml:1: error: Unsupported encoding UnsupportedEnc
2659&lt;?xml version="1.0" encoding="UnsupportedEnc"?&gt;
2660 ^</pre>
2661 </li>
Daniel Veillard46c5c1d2002-05-20 07:15:54 +0000[diff] [blame]2662 <li>From that point the encoder processes progressively the input (it is
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2663 plugged as a front-end to the I/O module) for that entity. It captures
2664 and convert on-the-fly the document to be parsed to UTF-8. The parser
2665 itself just does UTF-8 checking of this input and process it
2666 transparently. The only difference is that the encoding information has
2667 been added to the parsing context (more precisely to the input
2668 corresponding to this entity).</li>
2669 <li>The result (when using DOM) is an internal form completely in UTF-8
2670 with just an encoding information on the document node.</li>
2671</ol>
2672
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]2673<p>Ok then what happens when saving the document (assuming you
2674collected/built an xmlDoc DOM like structure) ? It depends on the function
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2675called, xmlSaveFile() will just try to save in the original encoding, while
2676xmlSaveFileTo() and xmlSaveFileEnc() can optionally save to a given
2677encoding:</p>
2678<ol>
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]2679 <li>if no encoding is given, libxml2 will look for an encoding value
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2680 associated to the document and if it exists will try to save to that
2681 encoding,
2682 <p>otherwise everything is written in the internal form, i.e. UTF-8</p>
2683 </li>
2684 <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]2685 document, libxml2 will again canonicalize the encoding name, lookup for a
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2686 converter in the registered set or through iconv. If not found the
2687 function will return an error code</li>
2688 <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]2689 buffer, then libxml2 will simply push the UTF-8 serialization to through
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2690 that buffer, which will then progressively be converted and pushed onto
2691 the I/O layer.</li>
2692 <li>It is possible that the converter code fails on some input, for example
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]2693 trying to push an UTF-8 encoded Chinese character through the UTF-8 to
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2694 ISO-8859-1 converter won't work. Since the encoders are progressive they
2695 will just report the error and the number of bytes converted, at that
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]2696 point libxml2 will decode the offending character, remove it from the
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2697 buffer and replace it with the associated charRef encoding &amp;#123; and
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]2698 resume the conversion. This guarantees that any document will be saved
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2699 without losses (except for markup names where this is not legal, this is
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]2700 a problem in the current version, in practice avoid using non-ascii
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2701 characters for tags or attributes names @@). A special "ascii" encoding
2702 name is used to save documents to a pure ascii form can be used when
2703 portability is really crucial</li>
2704</ol>
2705
2706<p>Here is a few examples based on the same test document:</p>
2707<pre>~/XML -&gt; ./xmllint isolat1
2708&lt;?xml version="1.0" encoding="ISO-8859-1"?&gt;
2709&lt;très&gt;là&lt;/très&gt;
2710~/XML -&gt; ./xmllint --encode UTF-8 isolat1
2711&lt;?xml version="1.0" encoding="UTF-8"?&gt;
2712&lt;très&gt;là  &lt;/très&gt;
2713~/XML -&gt; </pre>
2714
2715<p>The same processing is applied (and reuse most of the code) for HTML I18N
2716processing. Looking up and modifying the content encoding is a bit more
2717difficult since it is located in a &lt;meta&gt; tag under the &lt;head&gt;,
2718so a couple of functions htmlGetMetaEncoding() and htmlSetMetaEncoding() have
2719been provided. The parser also attempts to switch encoding on the fly when
2720detecting such a tag on input. Except for that the processing is the same
2721(and again reuses the same code).</p>
2722
2723<h3><a name="Default">Default supported encodings</a></h3>
2724
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]2725<p>libxml2 has a set of default converters for the following encodings
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2726(located in encoding.c):</p>
2727<ol>
2728 <li>UTF-8 is supported by default (null handlers)</li>
2729 <li>UTF-16, both little and big endian</li>
2730 <li>ISO-Latin-1 (ISO-8859-1) covering most western languages</li>
2731 <li>ASCII, useful mostly for saving</li>
2732 <li>HTML, a specific handler for the conversion of UTF-8 to ASCII with HTML
2733 predefined entities like &amp;copy; for the Copyright sign.</li>
2734</ol>
2735
Daniel Veillardc0801af2002-05-28 16:28:42 +0000[diff] [blame]2736<p>More over when compiled on an Unix platform with iconv support the full
2737set of encodings supported by iconv can be instantly be used by libxml. On a
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2738linux machine with glibc-2.1 the list of supported encodings and aliases fill
27393 full pages, and include UCS-4, the full set of ISO-Latin encodings, and the
2740various Japanese ones.</p>
2741
2742<h4>Encoding aliases</h4>
2743
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]2744<p>From 2.2.3, libxml2 has support to register encoding names aliases. The
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2745goal is to be able to parse document whose encoding is supported but where
2746the name differs (for example from the default set of names accepted by
2747iconv). The following functions allow to register and handle new aliases for
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]2748existing encodings. Once registered libxml2 will automatically lookup the
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2749aliases when handling a document:</p>
2750<ul>
2751 <li>int xmlAddEncodingAlias(const char *name, const char *alias);</li>
2752 <li>int xmlDelEncodingAlias(const char *alias);</li>
2753 <li>const char * xmlGetEncodingAlias(const char *alias);</li>
2754 <li>void xmlCleanupEncodingAliases(void);</li>
2755</ul>
2756
2757<h3><a name="extend">How to extend the existing support</a></h3>
2758
2759<p>Well adding support for new encoding, or overriding one of the encoders
2760(assuming it is buggy) should not be hard, just write an input and output
2761conversion routines to/from UTF-8, and register them using
2762xmlNewCharEncodingHandler(name, xxxToUTF8, UTF8Toxxx), and they will be
2763called automatically if the parser(s) encounter such an encoding name
2764(register it uppercase, this will help). The description of the encoders,
2765their arguments and expected return values are described in the encoding.h
2766header.</p>
2767
2768<p>A quick note on the topic of subverting the parser to use a different
2769internal encoding than UTF-8, in some case people will absolutely want to
2770keep the internal encoding different, I think it's still possible (but the
2771encoding must be compliant with ASCII on the same subrange) though I didn't
2772tried it. The key is to override the default conversion routines (by
2773registering null encoders/decoders for your charsets), and bypass the UTF-8
2774checking of the parser by setting the parser context charset
2775(ctxt-&gt;charset) to something different than XML_CHAR_ENCODING_UTF8, but
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]2776there is no guarantee that this will work. You may also have some troubles
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2777saving back.</p>
2778
2779<p>Basically proper I18N support is important, this requires at least
2780libxml-2.0.0, but a lot of features and corrections are really available only
2781starting 2.2.</p>
2782
2783<h2><a name="IO">I/O Interfaces</a></h2>
2784
2785<p>Table of Content:</p>
2786<ol>
2787 <li><a href="#General1">General overview</a></li>
2788 <li><a href="#basic">The basic buffer type</a></li>
2789 <li><a href="#Input">Input I/O handlers</a></li>
2790 <li><a href="#Output">Output I/O handlers</a></li>
2791 <li><a href="#entities">The entities loader</a></li>
2792 <li><a href="#Example2">Example of customized I/O</a></li>
2793</ol>
2794
2795<h3><a name="General1">General overview</a></h3>
2796
2797<p>The module <code><a
2798href="http://xmlsoft.org/html/libxml-xmlio.html">xmlIO.h</a></code> provides
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]2799the interfaces to the libxml2 I/O system. This consists of 4 main parts:</p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2800<ul>
2801 <li>Entities loader, this is a routine which tries to fetch the entities
2802 (files) based on their PUBLIC and SYSTEM identifiers. The default loader
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]2803 don't look at the public identifier since libxml2 do not maintain a
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2804 catalog. You can redefine you own entity loader by using
2805 <code>xmlGetExternalEntityLoader()</code> and
Daniel Veillard9c466822001-10-25 12:03:39 +0000[diff] [blame]2806 <code>xmlSetExternalEntityLoader()</code>. <a href="#entities">Check the
2807 example</a>.</li>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2808 <li>Input I/O buffers which are a commodity structure used by the parser(s)
2809 input layer to handle fetching the informations to feed the parser. This
2810 provides buffering and is also a placeholder where the encoding
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]2811 converters to UTF8 are piggy-backed.</li>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2812 <li>Output I/O buffers are similar to the Input ones and fulfill similar
2813 task but when generating a serialization from a tree.</li>
2814 <li>A mechanism to register sets of I/O callbacks and associate them with
2815 specific naming schemes like the protocol part of the URIs.
2816 <p>This affect the default I/O operations and allows to use specific I/O
2817 handlers for certain names.</p>
2818 </li>
2819</ul>
2820
2821<p>The general mechanism used when loading http://rpmfind.net/xml.html for
2822example in the HTML parser is the following:</p>
2823<ol>
2824 <li>The default entity loader calls <code>xmlNewInputFromFile()</code> with
2825 the parsing context and the URI string.</li>
2826 <li>the URI string is checked against the existing registered handlers
2827 using their match() callback function, if the HTTP module was compiled
2828 in, it is registered and its match() function will succeeds</li>
2829 <li>the open() function of the handler is called and if successful will
2830 return an I/O Input buffer</li>
2831 <li>the parser will the start reading from this buffer and progressively
2832 fetch information from the resource, calling the read() function of the
2833 handler until the resource is exhausted</li>
2834 <li>if an encoding change is detected it will be installed on the input
2835 buffer, providing buffering and efficient use of the conversion
2836 routines</li>
2837 <li>once the parser has finished, the close() function of the handler is
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]2838 called once and the Input buffer and associated resources are
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2839 deallocated.</li>
2840</ol>
2841
2842<p>The user defined callbacks are checked first to allow overriding of the
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]2843default libxml2 I/O routines.</p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2844
2845<h3><a name="basic">The basic buffer type</a></h3>
2846
2847<p>All the buffer manipulation handling is done using the
2848<code>xmlBuffer</code> type define in <code><a
2849href="http://xmlsoft.org/html/libxml-tree.html">tree.h</a> </code>which is a
2850resizable memory buffer. The buffer allocation strategy can be selected to be
2851either best-fit or use an exponential doubling one (CPU vs. memory use
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]2852trade-off). The values are <code>XML_BUFFER_ALLOC_EXACT</code> and
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2853<code>XML_BUFFER_ALLOC_DOUBLEIT</code>, and can be set individually or on a
2854system wide basis using <code>xmlBufferSetAllocationScheme()</code>. A number
2855of functions allows to manipulate buffers with names starting with the
2856<code>xmlBuffer...</code> prefix.</p>
2857
2858<h3><a name="Input">Input I/O handlers</a></h3>
2859
2860<p>An Input I/O handler is a simple structure
2861<code>xmlParserInputBuffer</code> containing a context associated to the
2862resource (file descriptor, or pointer to a protocol handler), the read() and
2863close() callbacks to use and an xmlBuffer. And extra xmlBuffer and a charset
2864encoding handler are also present to support charset conversion when
2865needed.</p>
2866
2867<h3><a name="Output">Output I/O handlers</a></h3>
2868
2869<p>An Output handler <code>xmlOutputBuffer</code> is completely similar to an
2870Input one except the callbacks are write() and close().</p>
2871
2872<h3><a name="entities">The entities loader</a></h3>
2873
2874<p>The entity loader resolves requests for new entities and create inputs for
2875the parser. Creating an input from a filename or an URI string is done
2876through the xmlNewInputFromFile() routine. The default entity loader do not
2877handle the PUBLIC identifier associated with an entity (if any). So it just
2878calls xmlNewInputFromFile() with the SYSTEM identifier (which is mandatory in
2879XML).</p>
2880
2881<p>If you want to hook up a catalog mechanism then you simply need to
2882override the default entity loader, here is an example:</p>
2883<pre>#include &lt;libxml/xmlIO.h&gt;
2884
2885xmlExternalEntityLoader defaultLoader = NULL;
2886
2887xmlParserInputPtr
2888xmlMyExternalEntityLoader(const char *URL, const char *ID,
2889 xmlParserCtxtPtr ctxt) {
2890 xmlParserInputPtr ret;
2891 const char *fileID = NULL;
2892 /* lookup for the fileID depending on ID */
2893
2894 ret = xmlNewInputFromFile(ctxt, fileID);
2895 if (ret != NULL)
2896 return(ret);
2897 if (defaultLoader != NULL)
2898 ret = defaultLoader(URL, ID, ctxt);
2899 return(ret);
2900}
2901
2902int main(..) {
2903 ...
2904
2905 /*
2906 * Install our own entity loader
2907 */
2908 defaultLoader = xmlGetExternalEntityLoader();
2909 xmlSetExternalEntityLoader(xmlMyExternalEntityLoader);
2910
2911 ...
2912}</pre>
2913
2914<h3><a name="Example2">Example of customized I/O</a></h3>
2915
2916<p>This example come from <a href="http://xmlsoft.org/messages/0708.html">a
2917real use case</a>, xmlDocDump() closes the FILE * passed by the application
2918and this was a problem. The <a
2919href="http://xmlsoft.org/messages/0711.html">solution</a> was to redefine a
2920new output handler with the closing call deactivated:</p>
2921<ol>
Daniel Veillardc0801af2002-05-28 16:28:42 +0000[diff] [blame]2922 <li>First define a new I/O output allocator where the output don't close
2923 the file:
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2924 <pre>xmlOutputBufferPtr
2925xmlOutputBufferCreateOwn(FILE *file, xmlCharEncodingHandlerPtr encoder) {
2926    xmlOutputBufferPtr ret;
2927    
2928    if (xmlOutputCallbackInitialized == 0)
2929        xmlRegisterDefaultOutputCallbacks();
2930
2931    if (file == NULL) return(NULL);
2932    ret = xmlAllocOutputBuffer(encoder);
2933    if (ret != NULL) {
2934        ret-&gt;context = file;
2935        ret-&gt;writecallback = xmlFileWrite;
2936        ret-&gt;closecallback = NULL; /* No close callback */
2937    }
Daniel Veillardf83a2c72003-04-08 13:48:40 +0000[diff] [blame]2938    return(ret);
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2939} </pre>
2940 </li>
2941 <li>And then use it to save the document:
2942 <pre>FILE *f;
2943xmlOutputBufferPtr output;
2944xmlDocPtr doc;
2945int res;
2946
2947f = ...
2948doc = ....
2949
2950output = xmlOutputBufferCreateOwn(f, NULL);
2951res = xmlSaveFileTo(output, doc, NULL);
2952 </pre>
2953 </li>
2954</ol>
2955
2956<h2><a name="Catalog">Catalog support</a></h2>
2957
2958<p>Table of Content:</p>
2959<ol>
2960 <li><a href="General2">General overview</a></li>
2961 <li><a href="#definition">The definition</a></li>
2962 <li><a href="#Simple">Using catalogs</a></li>
2963 <li><a href="#Some">Some examples</a></li>
2964 <li><a href="#reference">How to tune catalog usage</a></li>
2965 <li><a href="#validate">How to debug catalog processing</a></li>
2966 <li><a href="#Declaring">How to create and maintain catalogs</a></li>
2967 <li><a href="#implemento">The implementor corner quick review of the
2968 API</a></li>
2969 <li><a href="#Other">Other resources</a></li>
2970</ol>
2971
2972<h3><a name="General2">General overview</a></h3>
2973
2974<p>What is a catalog? Basically it's a lookup mechanism used when an entity
2975(a file or a remote resource) references another entity. The catalog lookup
2976is inserted between the moment the reference is recognized by the software
2977(XML parser, stylesheet processing, or even images referenced for inclusion
2978in a rendering) and the time where loading that resource is actually
2979started.</p>
2980
2981<p>It is basically used for 3 things:</p>
2982<ul>
2983 <li>mapping from "logical" names, the public identifiers and a more
2984 concrete name usable for download (and URI). For example it can associate
2985 the logical name
2986 <p>"-//OASIS//DTD DocBook XML V4.1.2//EN"</p>
2987 <p>of the DocBook 4.1.2 XML DTD with the actual URL where it can be
2988 downloaded</p>
2989 <p>http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd</p>
2990 </li>
2991 <li>remapping from a given URL to another one, like an HTTP indirection
2992 saying that
2993 <p>"http://www.oasis-open.org/committes/tr.xsl"</p>
2994 <p>should really be looked at</p>
2995 <p>"http://www.oasis-open.org/committes/entity/stylesheets/base/tr.xsl"</p>
2996 </li>
2997 <li>providing a local cache mechanism allowing to load the entities
2998 associated to public identifiers or remote resources, this is a really
2999 important feature for any significant deployment of XML or SGML since it
3000 allows to avoid the aleas and delays associated to fetching remote
3001 resources.</li>
3002</ul>
3003
3004<h3><a name="definition">The definitions</a></h3>
3005
3006<p>Libxml, as of 2.4.3 implements 2 kind of catalogs:</p>
3007<ul>
3008 <li>the older SGML catalogs, the official spec is SGML Open Technical
3009 Resolution TR9401:1997, but is better understood by reading <a
3010 href="http://www.jclark.com/sp/catalog.htm">the SP Catalog page</a> from
3011 James Clark. This is relatively old and not the preferred mode of
3012 operation of libxml.</li>
3013 <li><a href="http://www.oasis-open.org/committees/entity/spec.html">XML
Daniel Veillardaf43f632002-03-08 15:05:20 +0000[diff] [blame]3014 Catalogs</a> is far more flexible, more recent, uses an XML syntax and
3015 should scale quite better. This is the default option of libxml.</li>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]3016</ul>
3017
3018<p></p>
3019
3020<h3><a name="Simple">Using catalog</a></h3>
3021
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]3022<p>In a normal environment libxml2 will by default check the presence of a
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]3023catalog in /etc/xml/catalog, and assuming it has been correctly populated,
3024the processing is completely transparent to the document user. To take a
3025concrete example, suppose you are authoring a DocBook document, this one
3026starts with the following DOCTYPE definition:</p>
3027<pre>&lt;?xml version='1.0'?&gt;
3028&lt;!DOCTYPE book PUBLIC "-//Norman Walsh//DTD DocBk XML V3.1.4//EN"
3029 "http://nwalsh.com/docbook/xml/3.1.4/db3xml.dtd"&gt;</pre>
3030
3031<p>When validating the document with libxml, the catalog will be
3032automatically consulted to lookup the public identifier "-//Norman Walsh//DTD
3033DocBk XML V3.1.4//EN" and the system identifier
3034"http://nwalsh.com/docbook/xml/3.1.4/db3xml.dtd", and if these entities have
3035been installed on your system and the catalogs actually point to them, libxml
3036will fetch them from the local disk.</p>
3037
3038<p style="font-size: 10pt"><strong>Note</strong>: Really don't use this
3039DOCTYPE example it's a really old version, but is fine as an example.</p>
3040
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]3041<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]3042entity, this includes DTD, external parsed entities, stylesheets, etc ... If
3043your system is correctly configured all the authoring phase and processing
3044should use only local files, even if your document stays portable because it
3045uses the canonical public and system ID, referencing the remote document.</p>
3046
3047<h3><a name="Some">Some examples:</a></h3>
3048
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]3049<p>Here is a couple of fragments from XML Catalogs used in libxml2 early
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]3050regression tests in <code>test/catalogs</code> :</p>
3051<pre>&lt;?xml version="1.0"?&gt;
3052&lt;!DOCTYPE catalog PUBLIC
3053 "-//OASIS//DTD Entity Resolution XML Catalog V1.0//EN"
3054 "http://www.oasis-open.org/committees/entity/release/1.0/catalog.dtd"&gt;
3055&lt;catalog xmlns="urn:oasis:names:tc:entity:xmlns:xml:catalog"&gt;
3056 &lt;public publicId="-//OASIS//DTD DocBook XML V4.1.2//EN"
3057 uri="http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd"/&gt;
3058...</pre>
3059
3060<p>This is the beginning of a catalog for DocBook 4.1.2, XML Catalogs are
3061written in XML, there is a specific namespace for catalog elements
3062"urn:oasis:names:tc:entity:xmlns:xml:catalog". The first entry in this
3063catalog is a <code>public</code> mapping it allows to associate a Public
3064Identifier with an URI.</p>
3065<pre>...
3066 &lt;rewriteSystem systemIdStartString="http://www.oasis-open.org/docbook/"
3067 rewritePrefix="file:///usr/share/xml/docbook/"/&gt;
3068...</pre>
3069
3070<p>A <code>rewriteSystem</code> is a very powerful instruction, it says that
3071any URI starting with a given prefix should be looked at another URI
3072constructed by replacing the prefix with an new one. In effect this acts like
3073a cache system for a full area of the Web. In practice it is extremely useful
3074with a file prefix if you have installed a copy of those resources on your
3075local system.</p>
3076<pre>...
3077&lt;delegatePublic publicIdStartString="-//OASIS//DTD XML Catalog //"
3078 catalog="file:///usr/share/xml/docbook.xml"/&gt;
3079&lt;delegatePublic publicIdStartString="-//OASIS//ENTITIES DocBook XML"
3080 catalog="file:///usr/share/xml/docbook.xml"/&gt;
3081&lt;delegatePublic publicIdStartString="-//OASIS//DTD DocBook XML"
3082 catalog="file:///usr/share/xml/docbook.xml"/&gt;
3083&lt;delegateSystem systemIdStartString="http://www.oasis-open.org/docbook/"
3084 catalog="file:///usr/share/xml/docbook.xml"/&gt;
3085&lt;delegateURI uriStartString="http://www.oasis-open.org/docbook/"
3086 catalog="file:///usr/share/xml/docbook.xml"/&gt;
3087...</pre>
3088
3089<p>Delegation is the core features which allows to build a tree of catalogs,
3090easier to maintain than a single catalog, based on Public Identifier, System
3091Identifier or URI prefixes it instructs the catalog software to look up
3092entries in another resource. This feature allow to build hierarchies of
3093catalogs, the set of entries presented should be sufficient to redirect the
3094resolution of all DocBook references to the specific catalog in
3095<code>/usr/share/xml/docbook.xml</code> this one in turn could delegate all
3096references for DocBook 4.2.1 to a specific catalog installed at the same time
3097as the DocBook resources on the local machine.</p>
3098
3099<h3><a name="reference">How to tune catalog usage:</a></h3>
3100
3101<p>The user can change the default catalog behaviour by redirecting queries
3102to its own set of catalogs, this can be done by setting the
3103<code>XML_CATALOG_FILES</code> environment variable to a list of catalogs, an
3104empty one should deactivate loading the default <code>/etc/xml/catalog</code>
3105default catalog</p>
3106
3107<h3><a name="validate">How to debug catalog processing:</a></h3>
3108
3109<p>Setting up the <code>XML_DEBUG_CATALOG</code> environment variable will
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]3110make libxml2 output debugging informations for each catalog operations, for
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]3111example:</p>
3112<pre>orchis:~/XML -&gt; xmllint --memory --noout test/ent2
3113warning: failed to load external entity "title.xml"
3114orchis:~/XML -&gt; export XML_DEBUG_CATALOG=
3115orchis:~/XML -&gt; xmllint --memory --noout test/ent2
3116Failed to parse catalog /etc/xml/catalog
3117Failed to parse catalog /etc/xml/catalog
3118warning: failed to load external entity "title.xml"
3119Catalogs cleanup
3120orchis:~/XML -&gt; </pre>
3121
3122<p>The test/ent2 references an entity, running the parser from memory makes
3123the base URI unavailable and the the "title.xml" entity cannot be loaded.
3124Setting up the debug environment variable allows to detect that an attempt is
3125made to load the <code>/etc/xml/catalog</code> but since it's not present the
3126resolution fails.</p>
3127
3128<p>But the most advanced way to debug XML catalog processing is to use the
3129<strong>xmlcatalog</strong> command shipped with libxml2, it allows to load
3130catalogs and make resolution queries to see what is going on. This is also
3131used for the regression tests:</p>
3132<pre>orchis:~/XML -&gt; ./xmlcatalog test/catalogs/docbook.xml \
3133 "-//OASIS//DTD DocBook XML V4.1.2//EN"
3134http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd
3135orchis:~/XML -&gt; </pre>
3136
3137<p>For debugging what is going on, adding one -v flags increase the verbosity
3138level to indicate the processing done (adding a second flag also indicate
3139what elements are recognized at parsing):</p>
3140<pre>orchis:~/XML -&gt; ./xmlcatalog -v test/catalogs/docbook.xml \
3141 "-//OASIS//DTD DocBook XML V4.1.2//EN"
3142Parsing catalog test/catalogs/docbook.xml's content
3143Found public match -//OASIS//DTD DocBook XML V4.1.2//EN
3144http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd
3145Catalogs cleanup
3146orchis:~/XML -&gt; </pre>
3147
3148<p>A shell interface is also available to debug and process multiple queries
3149(and for regression tests):</p>
3150<pre>orchis:~/XML -&gt; ./xmlcatalog -shell test/catalogs/docbook.xml \
3151 "-//OASIS//DTD DocBook XML V4.1.2//EN"
3152&gt; help
3153Commands available:
3154public PublicID: make a PUBLIC identifier lookup
3155system SystemID: make a SYSTEM identifier lookup
3156resolve PublicID SystemID: do a full resolver lookup
3157add 'type' 'orig' 'replace' : add an entry
3158del 'values' : remove values
3159dump: print the current catalog state
3160debug: increase the verbosity level
3161quiet: decrease the verbosity level
3162exit: quit the shell
3163&gt; public "-//OASIS//DTD DocBook XML V4.1.2//EN"
3164http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd
3165&gt; quit
3166orchis:~/XML -&gt; </pre>
3167
3168<p>This should be sufficient for most debugging purpose, this was actually
3169used heavily to debug the XML Catalog implementation itself.</p>
3170
3171<h3><a name="Declaring">How to create and maintain</a> catalogs:</h3>
3172
3173<p>Basically XML Catalogs are XML files, you can either use XML tools to
3174manage them or use <strong>xmlcatalog</strong> for this. The basic step is
3175to create a catalog the -create option provide this facility:</p>
3176<pre>orchis:~/XML -&gt; ./xmlcatalog --create tst.xml
3177&lt;?xml version="1.0"?&gt;
3178&lt;!DOCTYPE catalog PUBLIC "-//OASIS//DTD Entity Resolution XML Catalog V1.0//EN"
3179 "http://www.oasis-open.org/committees/entity/release/1.0/catalog.dtd"&gt;
3180&lt;catalog xmlns="urn:oasis:names:tc:entity:xmlns:xml:catalog"/&gt;
3181orchis:~/XML -&gt; </pre>
3182
3183<p>By default xmlcatalog does not overwrite the original catalog and save the
3184result on the standard output, this can be overridden using the -noout
3185option. The <code>-add</code> command allows to add entries in the
3186catalog:</p>
3187<pre>orchis:~/XML -&gt; ./xmlcatalog --noout --create --add "public" \
3188 "-//OASIS//DTD DocBook XML V4.1.2//EN" \
3189 http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd tst.xml
3190orchis:~/XML -&gt; cat tst.xml
3191&lt;?xml version="1.0"?&gt;
3192&lt;!DOCTYPE catalog PUBLIC "-//OASIS//DTD Entity Resolution XML Catalog V1.0//EN" \
3193 "http://www.oasis-open.org/committees/entity/release/1.0/catalog.dtd"&gt;
3194&lt;catalog xmlns="urn:oasis:names:tc:entity:xmlns:xml:catalog"&gt;
3195&lt;public publicId="-//OASIS//DTD DocBook XML V4.1.2//EN"
3196 uri="http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd"/&gt;
3197&lt;/catalog&gt;
3198orchis:~/XML -&gt; </pre>
3199
3200<p>The <code>-add</code> option will always take 3 parameters even if some of
3201the XML Catalog constructs (like nextCatalog) will have only a single
3202argument, just pass a third empty string, it will be ignored.</p>
3203
3204<p>Similarly the <code>-del</code> option remove matching entries from the
3205catalog:</p>
3206<pre>orchis:~/XML -&gt; ./xmlcatalog --del \
3207 "http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd" tst.xml
3208&lt;?xml version="1.0"?&gt;
3209&lt;!DOCTYPE catalog PUBLIC "-//OASIS//DTD Entity Resolution XML Catalog V1.0//EN"
3210 "http://www.oasis-open.org/committees/entity/release/1.0/catalog.dtd"&gt;
3211&lt;catalog xmlns="urn:oasis:names:tc:entity:xmlns:xml:catalog"/&gt;
3212orchis:~/XML -&gt; </pre>
3213
3214<p>The catalog is now empty. Note that the matching of <code>-del</code> is
3215exact and would have worked in a similar fashion with the Public ID
3216string.</p>
3217
3218<p>This is rudimentary but should be sufficient to manage a not too complex
3219catalog tree of resources.</p>
3220
3221<h3><a name="implemento">The implementor corner quick review of the
3222API:</a></h3>
3223
3224<p>First, and like for every other module of libxml, there is an
3225automatically generated <a href="html/libxml-catalog.html">API page for
3226catalog support</a>.</p>
3227
3228<p>The header for the catalog interfaces should be included as:</p>
3229<pre>#include &lt;libxml/catalog.h&gt;</pre>
3230
3231<p>The API is voluntarily kept very simple. First it is not obvious that
3232applications really need access to it since it is the default behaviour of
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]3233libxml2 (Note: it is possible to completely override libxml2 default catalog by
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]3234using <a href="html/libxml-parser.html">xmlSetExternalEntityLoader</a> to
3235plug an application specific resolver).</p>
3236
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]3237<p>Basically libxml2 support 2 catalog lists:</p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]3238<ul>
3239 <li>the default one, global shared by all the application</li>
3240 <li>a per-document catalog, this one is built if the document uses the
3241 <code>oasis-xml-catalog</code> PIs to specify its own catalog list, it is
3242 associated to the parser context and destroyed when the parsing context
3243 is destroyed.</li>
3244</ul>
3245
3246<p>the document one will be used first if it exists.</p>
3247
3248<h4>Initialization routines:</h4>
3249
3250<p>xmlInitializeCatalog(), xmlLoadCatalog() and xmlLoadCatalogs() should be
3251used at startup to initialize the catalog, if the catalog should be
3252initialized with specific values xmlLoadCatalog() or xmlLoadCatalogs()
3253should be called before xmlInitializeCatalog() which would otherwise do a
3254default initialization first.</p>
3255
3256<p>The xmlCatalogAddLocal() call is used by the parser to grow the document
3257own catalog list if needed.</p>
3258
3259<h4>Preferences setup:</h4>
3260
3261<p>The XML Catalog spec requires the possibility to select default
3262preferences between public and system delegation,
3263xmlCatalogSetDefaultPrefer() allows this, xmlCatalogSetDefaults() and
3264xmlCatalogGetDefaults() allow to control if XML Catalogs resolution should
3265be forbidden, allowed for global catalog, for document catalog or both, the
3266default is to allow both.</p>
3267
3268<p>And of course xmlCatalogSetDebug() allows to generate debug messages
3269(through the xmlGenericError() mechanism).</p>
3270
3271<h4>Querying routines:</h4>
3272
3273<p>xmlCatalogResolve(), xmlCatalogResolveSystem(), xmlCatalogResolvePublic()
3274and xmlCatalogResolveURI() are relatively explicit if you read the XML
3275Catalog specification they correspond to section 7 algorithms, they should
3276also work if you have loaded an SGML catalog with a simplified semantic.</p>
3277
3278<p>xmlCatalogLocalResolve() and xmlCatalogLocalResolveURI() are the same but
3279operate on the document catalog list</p>
3280
3281<h4>Cleanup and Miscellaneous:</h4>
3282
3283<p>xmlCatalogCleanup() free-up the global catalog, xmlCatalogFreeLocal() is
3284the per-document equivalent.</p>
3285
3286<p>xmlCatalogAdd() and xmlCatalogRemove() are used to dynamically modify the
3287first catalog in the global list, and xmlCatalogDump() allows to dump a
3288catalog state, those routines are primarily designed for xmlcatalog, I'm not
3289sure that exposing more complex interfaces (like navigation ones) would be
3290really useful.</p>
3291
3292<p>The xmlParseCatalogFile() is a function used to load XML Catalog files,
3293it's similar as xmlParseFile() except it bypass all catalog lookups, it's
3294provided because this functionality may be useful for client tools.</p>
3295
3296<h4>threaded environments:</h4>
3297
3298<p>Since the catalog tree is built progressively, some care has been taken to
3299try to avoid troubles in multithreaded environments. The code is now thread
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]3300safe assuming that the libxml2 library has been compiled with threads
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]3301support.</p>
3302
3303<p></p>
3304
3305<h3><a name="Other">Other resources</a></h3>
3306
3307<p>The XML Catalog specification is relatively recent so there isn't much
3308literature to point at:</p>
3309<ul>
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]3310 <li>You can find a good rant from Norm Walsh about <a
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]3311 href="http://www.arbortext.com/Think_Tank/XML_Resources/Issue_Three/issue_three.html">the
3312 need for catalogs</a>, it provides a lot of context informations even if
Daniel Veillard93d3a472002-04-26 14:04:55 +0000[diff] [blame]3313 I don't agree with everything presented. Norm also wrote a more recent
3314 article <a
3315 href="http://wwws.sun.com/software/xml/developers/resolver/article/">XML
3316 entities and URI resolvers</a> describing them.</li>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]3317 <li>An <a href="http://home.ccil.org/~cowan/XML/XCatalog.html">old XML
3318 catalog proposal</a> from John Cowan</li>
3319 <li>The <a href="http://www.rddl.org/">Resource Directory Description
3320 Language</a> (RDDL) another catalog system but more oriented toward
3321 providing metadata for XML namespaces.</li>
3322 <li>the page from the OASIS Technical <a
3323 href="http://www.oasis-open.org/committees/entity/">Committee on Entity
3324 Resolution</a> who maintains XML Catalog, you will find pointers to the
3325 specification update, some background and pointers to others tools
3326 providing XML Catalog support</li>
Daniel Veillard35e937a2002-01-19 22:21:54 +0000[diff] [blame]3327 <li>Here is a <a href="buildDocBookCatalog">shell script</a> to generate
3328 XML Catalogs for DocBook 4.1.2 . If it can write to the /etc/xml/
3329 directory, it will set-up /etc/xml/catalog and /etc/xml/docbook based on
3330 the resources found on the system. Otherwise it will just create
3331 ~/xmlcatalog and ~/dbkxmlcatalog and doing:
Daniel Veillard8594de92003-04-25 10:08:44 +0000[diff] [blame]3332 <p><code>export XML_CATALOG_FILES=$HOME/xmlcatalog</code></p>
Daniel Veillard35e937a2002-01-19 22:21:54 +0000[diff] [blame]3333 <p>should allow to process DocBook documentations without requiring
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]3334 network accesses for the DTD or stylesheets</p>
Daniel Veillard35e937a2002-01-19 22:21:54 +0000[diff] [blame]3335 </li>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]3336 <li>I have uploaded <a href="ftp://xmlsoft.org/test/dbk412catalog.tar.gz">a
Daniel Veillard35e937a2002-01-19 22:21:54 +0000[diff] [blame]3337 small tarball</a> containing XML Catalogs for DocBook 4.1.2 which seems
3338 to work fine for me too</li>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]3339 <li>The <a href="http://www.xmlsoft.org/xmlcatalog_man.html">xmlcatalog
3340 manual page</a></li>
3341</ul>
3342
3343<p>If you have suggestions for corrections or additions, simply contact
3344me:</p>
3345
3346<h2><a name="library">The parser interfaces</a></h2>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3347
3348<p>This section is directly intended to help programmers getting bootstrapped
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]3349using the XML tollkit from the C language. It is not intended to be
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]3350extensive. I hope the automatically generated documents will provide the
3351completeness required, but as a separate set of documents. The interfaces of
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]3352the XML parser are by principle low level,
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]3353Those interested in a higher level API should <a href="#DOM">look at
3354DOM</a>.</p>
Daniel Veillardccb09631998-10-27 06:21:04 +0000[diff] [blame]3355
Daniel Veillard9cb5ff42001-01-29 08:22:21 +0000[diff] [blame]3356<p>The <a href="html/libxml-parser.html">parser interfaces for XML</a> are
3357separated from the <a href="html/libxml-htmlparser.html">HTML parser
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]3358interfaces</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]3359
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]3360<h3><a name="Invoking">Invoking the parser : the pull method</a></h3>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3361
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]3362<p>Usually, the first thing to do is to read an XML input. The parser accepts
3363documents either from in-memory strings or from files. The functions are
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3364defined in "parser.h":</p>
Daniel Veillard10c6a8f1998-10-28 01:00:12 +0000[diff] [blame]3365<dl>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3366 <dt><code>xmlDocPtr xmlParseMemory(char *buffer, int size);</code></dt>
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]3367 <dd><p>Parse a null-terminated string containing the document.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3368 </dd>
Daniel Veillard10c6a8f1998-10-28 01:00:12 +0000[diff] [blame]3369</dl>
3370<dl>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3371 <dt><code>xmlDocPtr xmlParseFile(const char *filename);</code></dt>
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]3372 <dd><p>Parse an XML document contained in a (possibly compressed)
3373 file.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3374 </dd>
Daniel Veillard10c6a8f1998-10-28 01:00:12 +0000[diff] [blame]3375</dl>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3376
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]3377<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]3378failure).</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3379
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]3380<h3 id="Invoking1">Invoking the parser: the push method</h3>
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]3381
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]3382<p>In order for the application to keep the control when the document is
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]3383being fetched (which is common for GUI based programs) libxml2 provides a push
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]3384interface, too, as of version 1.8.3. Here are the interface functions:</p>
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]3385<pre>xmlParserCtxtPtr xmlCreatePushParserCtxt(xmlSAXHandlerPtr sax,
3386 void *user_data,
3387 const char *chunk,
3388 int size,
3389 const char *filename);
3390int xmlParseChunk (xmlParserCtxtPtr ctxt,
3391 const char *chunk,
3392 int size,
3393 int terminate);</pre>
3394
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]3395<p>and here is a simple example showing how to use the interface:</p>
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]3396<pre> FILE *f;
3397
3398 f = fopen(filename, "r");
3399 if (f != NULL) {
3400 int res, size = 1024;
3401 char chars[1024];
3402 xmlParserCtxtPtr ctxt;
3403
3404 res = fread(chars, 1, 4, f);
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]3405 if (res &gt; 0) {
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]3406 ctxt = xmlCreatePushParserCtxt(NULL, NULL,
3407 chars, res, filename);
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]3408 while ((res = fread(chars, 1, size, f)) &gt; 0) {
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]3409 xmlParseChunk(ctxt, chars, res, 0);
3410 }
3411 xmlParseChunk(ctxt, chars, 0, 1);
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]3412 doc = ctxt-&gt;myDoc;
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]3413 xmlFreeParserCtxt(ctxt);
3414 }
3415 }</pre>
3416
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]3417<p>The HTML parser embedded into libxml2 also has a push interface; the
Daniel Veillardec70e912001-02-26 20:10:45 +0000[diff] [blame]3418functions are just prefixed by "html" rather than "xml".</p>
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]3419
3420<h3 id="Invoking2">Invoking the parser: the SAX interface</h3>
3421
Daniel Veillardec70e912001-02-26 20:10:45 +0000[diff] [blame]3422<p>The tree-building interface makes the parser memory-hungry, first loading
3423the document in memory and then building the tree itself. Reading a document
3424without building the tree is possible using the SAX interfaces (see SAX.h and
3425<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]3426Henstridge's documentation</a>). Note also that the push interface can be
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]3427limited to SAX: just use the two first arguments of
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]3428<code>xmlCreatePushParserCtxt()</code>.</p>
Daniel Veillardccb09631998-10-27 06:21:04 +0000[diff] [blame]3429
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]3430<h3><a name="Building">Building a tree from scratch</a></h3>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3431
3432<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]3433there is a set of functions dedicated to building new elements. (These are
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]3434also described in &lt;libxml/tree.h&gt;.) For example, here is a piece of
3435code that produces the XML document used in the previous examples:</p>
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]3436<pre> #include &lt;libxml/tree.h&gt;
Daniel Veillard361d8452000-04-03 19:48:13 +0000[diff] [blame]3437 xmlDocPtr doc;
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]3438 xmlNodePtr tree, subtree;
3439
3440 doc = xmlNewDoc("1.0");
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]3441 doc-&gt;children = xmlNewDocNode(doc, NULL, "EXAMPLE", NULL);
3442 xmlSetProp(doc-&gt;children, "prop1", "gnome is great");
3443 xmlSetProp(doc-&gt;children, "prop2", "&amp; linux too");
3444 tree = xmlNewChild(doc-&gt;children, NULL, "head", NULL);
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]3445 subtree = xmlNewChild(tree, NULL, "title", "Welcome to Gnome");
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]3446 tree = xmlNewChild(doc-&gt;children, NULL, "chapter", NULL);
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]3447 subtree = xmlNewChild(tree, NULL, "title", "The Linux adventure");
3448 subtree = xmlNewChild(tree, NULL, "p", "bla bla bla ...");
3449 subtree = xmlNewChild(tree, NULL, "image", NULL);
3450 xmlSetProp(subtree, "href", "linus.gif");</pre>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3451
3452<p>Not really rocket science ...</p>
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]3453
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]3454<h3><a name="Traversing">Traversing the tree</a></h3>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3455
Daniel Veillard9cb5ff42001-01-29 08:22:21 +0000[diff] [blame]3456<p>Basically by <a href="html/libxml-tree.html">including "tree.h"</a> your
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]3457code has access to the internal structure of all the elements of the tree.
3458The names should be somewhat simple like <strong>parent</strong>,
Daniel Veillard306be992000-07-03 12:38:45 +0000[diff] [blame]3459<strong>children</strong>, <strong>next</strong>, <strong>prev</strong>,
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]3460<strong>properties</strong>, etc... For example, still with the previous
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]3461example:</p>
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]3462<pre><code>doc-&gt;children-&gt;children-&gt;children</code></pre>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3463
3464<p>points to the title element,</p>
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]3465<pre>doc-&gt;children-&gt;children-&gt;next-&gt;children-&gt;children</pre>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3466
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]3467<p>points to the text node containing the chapter title "The Linux
3468adventure".</p>
Daniel Veillard10c6a8f1998-10-28 01:00:12 +0000[diff] [blame]3469
Daniel Veillardb24054a1999-12-18 15:32:46 +0000[diff] [blame]3470<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]3471present before the document root, so <code>doc-&gt;children</code> may point
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]3472to an element which is not the document Root Element; a function
Daniel Veillard5cb5ab81999-12-21 15:35:29 +0000[diff] [blame]3473<code>xmlDocGetRootElement()</code> was added for this purpose.</p>
Daniel Veillardb24054a1999-12-18 15:32:46 +0000[diff] [blame]3474
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]3475<h3><a name="Modifying">Modifying the tree</a></h3>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3476
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]3477<p>Functions are provided for reading and writing the document content. Here
Daniel Veillard9cb5ff42001-01-29 08:22:21 +0000[diff] [blame]3478is an excerpt from the <a href="html/libxml-tree.html">tree API</a>:</p>
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]3479<dl>
Daniel Veillarddd6b3671999-09-23 22:19:22 +0000[diff] [blame]3480 <dt><code>xmlAttrPtr xmlSetProp(xmlNodePtr node, const xmlChar *name, const
3481 xmlChar *value);</code></dt>
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]3482 <dd><p>This sets (or changes) an attribute carried by an ELEMENT node.
3483 The value can be NULL.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3484 </dd>
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]3485</dl>
3486<dl>
Daniel Veillarddd6b3671999-09-23 22:19:22 +0000[diff] [blame]3487 <dt><code>const xmlChar *xmlGetProp(xmlNodePtr node, const xmlChar
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3488 *name);</code></dt>
Daniel Veillardc92c3042000-09-29 02:42:04 +0000[diff] [blame]3489 <dd><p>This function returns a pointer to new copy of the property
3490 content. Note that the user must deallocate the result.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3491 </dd>
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]3492</dl>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3493
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]3494<p>Two functions are provided for reading and writing the text associated
3495with elements:</p>
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]3496<dl>
Daniel Veillarddd6b3671999-09-23 22:19:22 +0000[diff] [blame]3497 <dt><code>xmlNodePtr xmlStringGetNodeList(xmlDocPtr doc, const xmlChar
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3498 *value);</code></dt>
Daniel Veillardec70e912001-02-26 20:10:45 +0000[diff] [blame]3499 <dd><p>This function takes an "external" string and converts it to one
3500 text node or possibly to a list of entity and text nodes. All
3501 non-predefined entity references like &amp;Gnome; will be stored
3502 internally as entity nodes, hence the result of the function may not be
3503 a single node.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3504 </dd>
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]3505</dl>
3506<dl>
Daniel Veillarddd6b3671999-09-23 22:19:22 +0000[diff] [blame]3507 <dt><code>xmlChar *xmlNodeListGetString(xmlDocPtr doc, xmlNodePtr list, int
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3508 inLine);</code></dt>
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]3509 <dd><p>This function is the inverse of
3510 <code>xmlStringGetNodeList()</code>. It generates a new string
3511 containing the content of the text and entity nodes. Note the extra
3512 argument inLine. If this argument is set to 1, the function will expand
3513 entity references. For example, instead of returning the &amp;Gnome;
3514 XML encoding in the string, it will substitute it with its value (say,
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]3515 "GNU Network Object Model Environment").</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3516 </dd>
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]3517</dl>
Daniel Veillard10c6a8f1998-10-28 01:00:12 +0000[diff] [blame]3518
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]3519<h3><a name="Saving">Saving a tree</a></h3>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3520
3521<p>Basically 3 options are possible:</p>
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]3522<dl>
Daniel Veillarddd6b3671999-09-23 22:19:22 +0000[diff] [blame]3523 <dt><code>void xmlDocDumpMemory(xmlDocPtr cur, xmlChar**mem, int
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3524 *size);</code></dt>
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]3525 <dd><p>Returns a buffer into which the document has been saved.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3526 </dd>
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]3527</dl>
3528<dl>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3529 <dt><code>extern void xmlDocDump(FILE *f, xmlDocPtr doc);</code></dt>
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]3530 <dd><p>Dumps a document to an open file descriptor.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3531 </dd>
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]3532</dl>
3533<dl>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3534 <dt><code>int xmlSaveFile(const char *filename, xmlDocPtr cur);</code></dt>
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]3535 <dd><p>Saves the document to a file. In this case, the compression
3536 interface is triggered if it has been turned on.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3537 </dd>
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]3538</dl>
Daniel Veillard10c6a8f1998-10-28 01:00:12 +0000[diff] [blame]3539
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]3540<h3><a name="Compressio">Compression</a></h3>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3541
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]3542<p>The library transparently handles compression when doing file-based
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]3543accesses. The level of compression on saves can be turned on either globally
3544or individually for one file:</p>
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]3545<dl>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3546 <dt><code>int xmlGetDocCompressMode (xmlDocPtr doc);</code></dt>
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]3547 <dd><p>Gets the document compression ratio (0-9).</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3548 </dd>
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]3549</dl>
3550<dl>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3551 <dt><code>void xmlSetDocCompressMode (xmlDocPtr doc, int mode);</code></dt>
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]3552 <dd><p>Sets the document compression ratio.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3553 </dd>
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]3554</dl>
3555<dl>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3556 <dt><code>int xmlGetCompressMode(void);</code></dt>
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]3557 <dd><p>Gets the default compression ratio.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3558 </dd>
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]3559</dl>
3560<dl>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3561 <dt><code>void xmlSetCompressMode(int mode);</code></dt>
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]3562 <dd><p>Sets the default compression ratio.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3563 </dd>
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]3564</dl>
3565
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]3566<h2><a name="Entities">Entities or no entities</a></h2>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]3567
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]3568<p>Entities in principle are similar to simple C macros. An entity defines an
3569abbreviation for a given string that you can reuse many times throughout the
3570content of your document. Entities are especially useful when a given string
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]3571may occur frequently within a document, or to confine the change needed to a
3572document to a restricted area in the internal subset of the document (at the
3573beginning). Example:</p>
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]3574<pre>1 &lt;?xml version="1.0"?&gt;
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]35752 &lt;!DOCTYPE EXAMPLE SYSTEM "example.dtd" [
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]35763 &lt;!ENTITY xml "Extensible Markup Language"&gt;
35774 ]&gt;
35785 &lt;EXAMPLE&gt;
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]35796 &amp;xml;
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]35807 &lt;/EXAMPLE&gt;</pre>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]3581
3582<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]3583its name with '&amp;' and following it by ';' without any spaces added. There
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]3584are 5 predefined entities in libxml2 allowing you to escape characters with
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]3585predefined meaning in some parts of the xml document content:
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]3586<strong>&amp;lt;</strong> for the character '&lt;', <strong>&amp;gt;</strong>
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]3587for the character '&gt;', <strong>&amp;apos;</strong> for the character ''',
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]3588<strong>&amp;quot;</strong> for the character '"', and
3589<strong>&amp;amp;</strong> for the character '&amp;'.</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]3590
3591<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]3592substitute an entity's content so that you can see the replacement text in
3593your application. Or you may prefer to keep entity references as such in the
3594content to be able to save the document back without losing this usually
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]3595precious information (if the user went through the pain of explicitly
3596defining entities, he may have a a rather negative attitude if you blindly
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]3597substitute them as saving time). The <a
Daniel Veillard9cb5ff42001-01-29 08:22:21 +0000[diff] [blame]3598href="html/libxml-parser.html#XMLSUBSTITUTEENTITIESDEFAULT">xmlSubstituteEntitiesDefault()</a>
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]3599function allows you to check and change the behaviour, which is to not
3600substitute entities by default.</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]3601
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]3602<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]3603default case:</p>
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]3604<pre>/gnome/src/gnome-xml -&gt; ./xmllint --debug test/ent1
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]3605DOCUMENT
3606version=1.0
3607 ELEMENT EXAMPLE
3608 TEXT
3609 content=
3610 ENTITY_REF
3611 INTERNAL_GENERAL_ENTITY xml
3612 content=Extensible Markup Language
3613 TEXT
3614 content=</pre>
3615
3616<p>And here is the result when substituting entities:</p>
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]3617<pre>/gnome/src/gnome-xml -&gt; ./tester --debug --noent test/ent1
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]3618DOCUMENT
3619version=1.0
3620 ELEMENT EXAMPLE
3621 TEXT
3622 content= Extensible Markup Language</pre>
3623
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]3624<p>So, entities or no entities? Basically, it depends on your use case. I
3625suggest that you keep the non-substituting default behaviour and avoid using
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]3626entities in your XML document or data if you are not willing to handle the
3627entity references elements in the DOM tree.</p>
3628
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]3629<p>Note that at save time libxml2 enforces the conversion of the predefined
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]3630entities where necessary to prevent well-formedness problems, and will also
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]3631transparently replace those with chars (i.e. it will not generate entity
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]3632reference elements in the DOM tree or call the reference() SAX callback when
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]3633finding them in the input).</p>
3634
Daniel Veillard7b9c4b72000-08-25 16:26:50 +0000[diff] [blame]3635<p><span style="background-color: #FF0000">WARNING</span>: handling entities
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]3636on top of the libxml2 SAX interface is difficult!!! If you plan to use
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]3637non-predefined entities in your documents, then the learning curve to handle
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]3638then 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]3639strongly suggest you consider using the DOM interface instead and let libxml
Daniel Veillard8c6d6af2000-08-25 17:14:13 +0000[diff] [blame]3640deal with the complexity rather than trying to do it yourself.</p>
Daniel Veillard7b9c4b72000-08-25 16:26:50 +0000[diff] [blame]3641
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]3642<h2><a name="Namespaces">Namespaces</a></h2>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]3643
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]3644<p>The libxml2 library implements <a
Daniel Veillardec303412000-03-24 13:41:54 +0000[diff] [blame]3645href="http://www.w3.org/TR/REC-xml-names/">XML namespaces</a> support by
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]3646recognizing namespace constructs in the input, and does namespace lookup
Daniel Veillardec303412000-03-24 13:41:54 +0000[diff] [blame]3647automatically when building the DOM tree. A namespace declaration is
3648associated with an in-memory structure and all elements or attributes within
3649that namespace point to it. Hence testing the namespace is a simple and fast
3650equality operation at the user level.</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]3651
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]3652<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]3653root element of their document as the default namespace. Then they don't need
3654to 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]3655refinement and merging of data from different sources. This doesn't increase
Daniel Veillardec70e912001-02-26 20:10:45 +0000[diff] [blame]3656the size of the XML output significantly, but significantly increases its
3657value in the long-term. Example:</p>
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]3658<pre>&lt;mydoc xmlns="http://mydoc.example.org/schemas/"&gt;
3659 &lt;elem1&gt;...&lt;/elem1&gt;
3660 &lt;elem2&gt;...&lt;/elem2&gt;
3661&lt;/mydoc&gt;</pre>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]3662
Daniel Veillardec70e912001-02-26 20:10:45 +0000[diff] [blame]3663<p>The namespace value has to be an absolute URL, but the URL doesn't have to
3664point to any existing resource on the Web. It will bind all the element and
Daniel Veillardc0801af2002-05-28 16:28:42 +0000[diff] [blame]3665attributes with that URL. I suggest to use an URL within a domain you
3666control, and that the URL should contain some kind of version information if
3667possible. For example, <code>"http://www.gnome.org/gnumeric/1.0/"</code> is a
3668good namespace scheme.</p>
Daniel Veillardec303412000-03-24 13:41:54 +0000[diff] [blame]3669
3670<p>Then when you load a file, make sure that a namespace carrying the
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]3671version-independent prefix is installed on the root element of your document,
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]3672and if the version information don't match something you know, warn the user
3673and 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]3674namespace checking on the prefix value. &lt;foo:text&gt; may be exactly the
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]3675same as &lt;bar:text&gt; in another document. What really matters is the URI
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]3676associated with the element or the attribute, not the prefix string (which is
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]3677just a shortcut for the full URI). In libxml, element and attributes have an
Daniel Veillardec303412000-03-24 13:41:54 +0000[diff] [blame]3678<code>ns</code> field pointing to an xmlNs structure detailing the namespace
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]3679prefix and its URI.</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]3680
3681<p>@@Interfaces@@</p>
3682
3683<p>@@Examples@@</p>
3684
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]3685<p>Usually people object to using namespaces together with validity checking.
3686I will try to make sure that using namespaces won't break validity checking,
3687so even if you plan to use or currently are using validation I strongly
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]3688suggest adding namespaces to your document. A default namespace scheme
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]3689<code>xmlns="http://...."</code> should not break validity even on less
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]3690flexible parsers. Using namespaces to mix and differentiate content coming
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]3691from multiple DTDs will certainly break current validation schemes. I will
3692try to provide ways to do this, but this may not be portable or
3693standardized.</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]3694
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]3695<h2><a name="Upgrading">Upgrading 1.x code</a></h2>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]3696
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]3697<p>Incompatible changes:</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]3698
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]3699<p>Version 2 of libxml2 is the first version introducing serious backward
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]3700incompatible changes. The main goals were:</p>
3701<ul>
3702 <li>a general cleanup. A number of mistakes inherited from the very early
3703 versions couldn't be changed due to compatibility constraints. Example
3704 the "childs" element in the nodes.</li>
3705 <li>Uniformization of the various nodes, at least for their header and link
3706 parts (doc, parent, children, prev, next), the goal is a simpler
3707 programming model and simplifying the task of the DOM implementors.</li>
3708 <li>better conformances to the XML specification, for example version 1.x
3709 had an heuristic to try to detect ignorable white spaces. As a result the
3710 SAX event generated were ignorableWhitespace() while the spec requires
3711 character() in that case. This also mean that a number of DOM node
3712 containing blank text may populate the DOM tree which were not present
3713 before.</li>
3714</ul>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]3715
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]3716<h3>How to fix libxml-1.x code:</h3>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]3717
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]3718<p>So client code of libxml designed to run with version 1.x may have to be
3719changed to compile against version 2.x of libxml. Here is a list of changes
3720that I have collected, they may not be sufficient, so in case you find other
3721change which are required, <a href="mailto:Daniel.Ïeillardw3.org">drop me a
3722mail</a>:</p>
3723<ol>
3724 <li>The package name have changed from libxml to libxml2, the library name
3725 is now -lxml2 . There is a new xml2-config script which should be used to
3726 select the right parameters libxml2</li>
3727 <li>Node <strong>childs</strong> field has been renamed
3728 <strong>children</strong> so s/childs/children/g should be applied
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]3729 (probability of having "childs" anywhere else is close to 0+</li>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]3730 <li>The document don't have anymore a <strong>root</strong> element it has
3731 been replaced by <strong>children</strong> and usually you will get a
3732 list of element here. For example a Dtd element for the internal subset
3733 and it's declaration may be found in that list, as well as processing
3734 instructions or comments found before or after the document root element.
3735 Use <strong>xmlDocGetRootElement(doc)</strong> to get the root element of
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]3736 a document. Alternatively if you are sure to not reference DTDs nor have
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]3737 PIs or comments before or after the root element
3738 s/-&gt;root/-&gt;children/g will probably do it.</li>
3739 <li>The white space issue, this one is more complex, unless special case of
3740 validating parsing, the line breaks and spaces usually used for indenting
3741 and formatting the document content becomes significant. So they are
3742 reported by SAX and if your using the DOM tree, corresponding nodes are
3743 generated. Too approach can be taken:
3744 <ol>
3745 <li>lazy one, use the compatibility call
3746 <strong>xmlKeepBlanksDefault(0)</strong> but be aware that you are
3747 relying on a special (and possibly broken) set of heuristics of
3748 libxml to detect ignorable blanks. Don't complain if it breaks or
3749 make your application not 100% clean w.r.t. to it's input.</li>
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]3750 <li>the Right Way: change you code to accept possibly insignificant
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]3751 blanks characters, or have your tree populated with weird blank text
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]3752 nodes. You can spot them using the commodity function
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]3753 <strong>xmlIsBlankNode(node)</strong> returning 1 for such blank
3754 nodes.</li>
3755 </ol>
3756 <p>Note also that with the new default the output functions don't add any
3757 extra indentation when saving a tree in order to be able to round trip
3758 (read and save) without inflating the document with extra formatting
3759 chars.</p>
3760 </li>
3761 <li>The include path has changed to $prefix/libxml/ and the includes
3762 themselves uses this new prefix in includes instructions... If you are
3763 using (as expected) the
3764 <pre>xml2-config --cflags</pre>
3765 <p>output to generate you compile commands this will probably work out of
3766 the box</p>
3767 </li>
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]3768 <li>xmlDetectCharEncoding takes an extra argument indicating the length in
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]3769 byte of the head of the document available for character detection.</li>
3770</ol>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]3771
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]3772<h3>Ensuring both libxml-1.x and libxml-2.x compatibility</h3>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]3773
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]3774<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]3775to allow smooth upgrade of existing libxml v1code while retaining
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]3776compatibility. They offers the following:</p>
3777<ol>
3778 <li>similar include naming, one should use
3779 <strong>#include&lt;libxml/...&gt;</strong> in both cases.</li>
3780 <li>similar identifiers defined via macros for the child and root fields:
3781 respectively <strong>xmlChildrenNode</strong> and
3782 <strong>xmlRootNode</strong></li>
3783 <li>a new macro <strong>LIBXML_TEST_VERSION</strong> which should be
3784 inserted once in the client code</li>
3785</ol>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]3786
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]3787<p>So the roadmap to upgrade your existing libxml applications is the
3788following:</p>
3789<ol>
3790 <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]3791 <li>find all occurrences where the xmlDoc <strong>root</strong> field is
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]3792 used and change it to <strong>xmlRootNode</strong></li>
Daniel Veillardc0801af2002-05-28 16:28:42 +0000[diff] [blame]3793 <li>similarly find all occurrences where the xmlNode
3794 <strong>childs</strong> field is used and change it to
3795 <strong>xmlChildrenNode</strong></li>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]3796 <li>add a <strong>LIBXML_TEST_VERSION</strong> macro somewhere in your
3797 <strong>main()</strong> or in the library init entry point</li>
3798 <li>Recompile, check compatibility, it should still work</li>
Daniel Veillardc0801af2002-05-28 16:28:42 +0000[diff] [blame]3799 <li>Change your configure script to look first for xml2-config and fall
3800 back using xml-config . Use the --cflags and --libs output of the command
3801 as the Include and Linking parameters needed to use libxml.</li>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]3802 <li>install libxml2-2.3.x and libxml2-devel-2.3.x (libxml-1.8.y and
3803 libxml-devel-1.8.y can be kept simultaneously)</li>
3804 <li>remove your config.cache, relaunch your configuration mechanism, and
3805 recompile, if steps 2 and 3 were done right it should compile as-is</li>
3806 <li>Test that your application is still running correctly, if not this may
3807 be due to extra empty nodes due to formating spaces being kept in libxml2
3808 contrary to libxml1, in that case insert xmlKeepBlanksDefault(1) in your
3809 code before calling the parser (next to
3810 <strong>LIBXML_TEST_VERSION</strong> is a fine place).</li>
3811</ol>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]3812
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]3813<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]3814
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]3815<p>Let me put some emphasis on the fact that there is far more changes from
3816libxml 1.x to 2.x than the ones you may have to patch for. The overall code
3817has been considerably cleaned up and the conformance to the XML specification
3818has been drastically improved too. Don't take those changes as an excuse to
3819not upgrade, it may cost a lot on the long term ...</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]3820
Daniel Veillard52dcab32001-10-30 12:51:17 +0000[diff] [blame]3821<h2><a name="Thread">Thread safety</a></h2>
3822
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]3823<p>Starting with 2.4.7, libxml2 makes provisions to ensure that concurrent
Daniel Veillard52dcab32001-10-30 12:51:17 +0000[diff] [blame]3824threads can safely work in parallel parsing different documents. There is
3825however a couple of things to do to ensure it:</p>
3826<ul>
3827 <li>configure the library accordingly using the --with-threads options</li>
3828 <li>call xmlInitParser() in the "main" thread before using any of the
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]3829 libxml2 API (except possibly selecting a different memory allocator)</li>
Daniel Veillard52dcab32001-10-30 12:51:17 +0000[diff] [blame]3830</ul>
3831
3832<p>Note that the thread safety cannot be ensured for multiple threads sharing
3833the same document, the locking must be done at the application level, libxml
3834exports a basic mutex and reentrant mutexes API in &lt;libxml/threads.h&gt;.
3835The parts of the library checked for thread safety are:</p>
3836<ul>
3837 <li>concurrent loading</li>
3838 <li>file access resolution</li>
3839 <li>catalog access</li>
3840 <li>catalog building</li>
3841 <li>entities lookup/accesses</li>
3842 <li>validation</li>
3843 <li>global variables per-thread override</li>
3844 <li>memory handling</li>
3845</ul>
3846
3847<p>XPath is supposed to be thread safe now, but this wasn't tested
3848seriously.</p>
3849
Daniel Veillard35008381999-10-25 13:15:52 +0000[diff] [blame]3850<h2><a name="DOM"></a><a name="Principles">DOM Principles</a></h2>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3851
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]3852<p><a href="http://www.w3.org/DOM/">DOM</a> stands for the <em>Document
3853Object Model</em>; this is an API for accessing XML or HTML structured
3854documents. Native support for DOM in Gnome is on the way (module gnome-dom),
3855and will be based on gnome-xml. This will be a far cleaner interface to
3856manipulate XML files within Gnome since it won't expose the internal
3857structure.</p>
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]3858
Daniel Veillard8a469172003-06-12 16:05:07 +0000[diff] [blame]3859<p>The current DOM implementation on top of libxml2 is the <a
Daniel Veillarda47fb3d2001-03-25 17:23:49 +0000[diff] [blame]3860href="http://cvs.gnome.org/lxr/source/gdome2/">gdome2 Gnome module</a>, this
3861is a full DOM interface, thanks to Paolo Casarini, check the <a
3862href="http://www.cs.unibo.it/~casarini/gdome2/">Gdome2 homepage</a> for more
3863informations.</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]3864
Daniel Veillard35008381999-10-25 13:15:52 +0000[diff] [blame]3865<h2><a name="Example"></a><a name="real">A real example</a></h2>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3866
3867<p>Here is a real size example, where the actual content of the application
3868data 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]3869a proposal to keep a database of jobs related to Gnome, with an XML based
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3870storage structure. Here is an <a href="gjobs.xml">XML encoded jobs
3871base</a>:</p>
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]3872<pre>&lt;?xml version="1.0"?&gt;
3873&lt;gjob:Helping xmlns:gjob="http://www.gnome.org/some-location"&gt;
3874 &lt;gjob:Jobs&gt;
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]3875
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]3876 &lt;gjob:Job&gt;
3877 &lt;gjob:Project ID="3"/&gt;
3878 &lt;gjob:Application&gt;GBackup&lt;/gjob:Application&gt;
3879 &lt;gjob:Category&gt;Development&lt;/gjob:Category&gt;
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]3880
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]3881 &lt;gjob:Update&gt;
3882 &lt;gjob:Status&gt;Open&lt;/gjob:Status&gt;
3883 &lt;gjob:Modified&gt;Mon, 07 Jun 1999 20:27:45 -0400 MET DST&lt;/gjob:Modified&gt;
3884 &lt;gjob:Salary&gt;USD 0.00&lt;/gjob:Salary&gt;
3885 &lt;/gjob:Update&gt;
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]3886
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]3887 &lt;gjob:Developers&gt;
3888 &lt;gjob:Developer&gt;
3889 &lt;/gjob:Developer&gt;
3890 &lt;/gjob:Developers&gt;
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]3891
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]3892 &lt;gjob:Contact&gt;
3893 &lt;gjob:Person&gt;Nathan Clemons&lt;/gjob:Person&gt;
3894 &lt;gjob:Email&gt;nathan@windsofstorm.net&lt;/gjob:Email&gt;
3895 &lt;gjob:Company&gt;
3896 &lt;/gjob:Company&gt;
3897 &lt;gjob:Organisation&gt;
3898 &lt;/gjob:Organisation&gt;
3899 &lt;gjob:Webpage&gt;
3900 &lt;/gjob:Webpage&gt;
3901 &lt;gjob:Snailmail&gt;
3902 &lt;/gjob:Snailmail&gt;
3903 &lt;gjob:Phone&gt;
3904 &lt;/gjob:Phone&gt;
3905 &lt;/gjob:Contact&gt;
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]3906
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]3907 &lt;gjob:Requirements&gt;
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]3908 The program should be released as free software, under the GPL.
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]3909 &lt;/gjob:Requirements&gt;
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]3910
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]3911 &lt;gjob:Skills&gt;
3912 &lt;/gjob:Skills&gt;
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]3913
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]3914 &lt;gjob:Details&gt;
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]3915 A GNOME based system that will allow a superuser to configure
3916 compressed and uncompressed files and/or file systems to be backed
3917 up with a supported media in the system. This should be able to
3918 perform via find commands generating a list of files that are passed
3919 to tar, dd, cpio, cp, gzip, etc., to be directed to the tape machine
3920 or via operations performed on the filesystem itself. Email
3921 notification and GUI status display very important.
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]3922 &lt;/gjob:Details&gt;
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]3923
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]3924 &lt;/gjob:Job&gt;
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]3925
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]3926 &lt;/gjob:Jobs&gt;
3927&lt;/gjob:Helping&gt;</pre>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3928
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]3929<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]3930calling only a couple of functions, browsing the tree to gather the data and
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]3931generate the internal structures is harder, and more error prone.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3932
3933<p>The suggested principle is to be tolerant with respect to the input
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]3934structure. For example, the ordering of the attributes is not significant,
3935the 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]3936depend on the order of the children of a given node, unless it really makes
3937things harder. Here is some code to parse the information for a person:</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3938<pre>/*
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]3939 * A person record
3940 */
3941typedef struct person {
3942 char *name;
3943 char *email;
3944 char *company;
3945 char *organisation;
3946 char *smail;
3947 char *webPage;
3948 char *phone;
3949} person, *personPtr;
3950
3951/*
3952 * And the code needed to parse it
3953 */
3954personPtr parsePerson(xmlDocPtr doc, xmlNsPtr ns, xmlNodePtr cur) {
3955 personPtr ret = NULL;
3956
3957DEBUG("parsePerson\n");
3958 /*
3959 * allocate the struct
3960 */
3961 ret = (personPtr) malloc(sizeof(person));
3962 if (ret == NULL) {
3963 fprintf(stderr,"out of memory\n");
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3964 return(NULL);
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]3965 }
3966 memset(ret, 0, sizeof(person));
3967
3968 /* We don't care what the top level element name is */
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]3969 cur = cur-&gt;xmlChildrenNode;
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]3970 while (cur != NULL) {
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]3971 if ((!strcmp(cur-&gt;name, "Person")) &amp;&amp; (cur-&gt;ns == ns))
3972 ret-&gt;name = xmlNodeListGetString(doc, cur-&gt;xmlChildrenNode, 1);
3973 if ((!strcmp(cur-&gt;name, "Email")) &amp;&amp; (cur-&gt;ns == ns))
3974 ret-&gt;email = xmlNodeListGetString(doc, cur-&gt;xmlChildrenNode, 1);
3975 cur = cur-&gt;next;
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]3976 }
3977
3978 return(ret);
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3979}</pre>
3980
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]3981<p>Here are a couple of things to notice:</p>
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]3982<ul>
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]3983 <li>Usually a recursive parsing style is the more convenient one: XML data
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]3984 is by nature subject to repetitive constructs and usually exhibits highly
3985 structured patterns.</li>
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]3986 <li>The two arguments of type <em>xmlDocPtr</em> and <em>xmlNsPtr</em>,
3987 i.e. the pointer to the global XML document and the namespace reserved to
3988 the application. Document wide information are needed for example to
3989 decode entities and it's a good coding practice to define a namespace for
3990 your application set of data and test that the element and attributes
3991 you're analyzing actually pertains to your application space. This is
3992 done by a simple equality test (cur-&gt;ns == ns).</li>
Daniel Veillardec70e912001-02-26 20:10:45 +0000[diff] [blame]3993 <li>To retrieve text and attributes value, you can use the function
3994 <em>xmlNodeListGetString</em> to gather all the text and entity reference
3995 nodes generated by the DOM output and produce an single text string.</li>
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]3996</ul>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3997
3998<p>Here is another piece of code used to parse another level of the
3999structure:</p>
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]4000<pre>#include &lt;libxml/tree.h&gt;
Daniel Veillard361d8452000-04-03 19:48:13 +0000[diff] [blame]4001/*
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]4002 * a Description for a Job
4003 */
4004typedef struct job {
4005 char *projectID;
4006 char *application;
4007 char *category;
4008 personPtr contact;
4009 int nbDevelopers;
4010 personPtr developers[100]; /* using dynamic alloc is left as an exercise */
4011} job, *jobPtr;
4012
4013/*
4014 * And the code needed to parse it
4015 */
4016jobPtr parseJob(xmlDocPtr doc, xmlNsPtr ns, xmlNodePtr cur) {
4017 jobPtr ret = NULL;
4018
4019DEBUG("parseJob\n");
4020 /*
4021 * allocate the struct
4022 */
4023 ret = (jobPtr) malloc(sizeof(job));
4024 if (ret == NULL) {
4025 fprintf(stderr,"out of memory\n");
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]4026 return(NULL);
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]4027 }
4028 memset(ret, 0, sizeof(job));
4029
4030 /* We don't care what the top level element name is */
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]4031 cur = cur-&gt;xmlChildrenNode;
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]4032 while (cur != NULL) {
4033
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]4034 if ((!strcmp(cur-&gt;name, "Project")) &amp;&amp; (cur-&gt;ns == ns)) {
4035 ret-&gt;projectID = xmlGetProp(cur, "ID");
4036 if (ret-&gt;projectID == NULL) {
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]4037 fprintf(stderr, "Project has no ID\n");
4038 }
4039 }
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]4040 if ((!strcmp(cur-&gt;name, "Application")) &amp;&amp; (cur-&gt;ns == ns))
4041 ret-&gt;application = xmlNodeListGetString(doc, cur-&gt;xmlChildrenNode, 1);
4042 if ((!strcmp(cur-&gt;name, "Category")) &amp;&amp; (cur-&gt;ns == ns))
4043 ret-&gt;category = xmlNodeListGetString(doc, cur-&gt;xmlChildrenNode, 1);
4044 if ((!strcmp(cur-&gt;name, "Contact")) &amp;&amp; (cur-&gt;ns == ns))
4045 ret-&gt;contact = parsePerson(doc, ns, cur);
4046 cur = cur-&gt;next;
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]4047 }
4048
4049 return(ret);
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]4050}</pre>
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]4051
Daniel Veillardec70e912001-02-26 20:10:45 +0000[diff] [blame]4052<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]4053boring. Ultimately, it could be possible to write stubbers taking either C
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]4054data structure definitions, a set of XML examples or an XML DTD and produce
4055the code needed to import and export the content between C data and XML
4056storage. This is left as an exercise to the reader :-)</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]4057
Daniel Veillard6f0adb52000-07-03 11:41:26 +0000[diff] [blame]4058<p>Feel free to use <a href="example/gjobread.c">the code for the full C
4059parsing example</a> as a template, it is also available with Makefile in the
4060Gnome CVS base under gnome-xml/example</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]4061
Daniel Veillardc310d562000-06-23 18:32:15 +0000[diff] [blame]4062<h2><a name="Contributi">Contributions</a></h2>
4063<ul>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]4064 <li>Bjorn Reese, William Brack and Thomas Broyer have provided a number of
4065 patches, Gary Pennington worked on the validation API, threading support
4066 and Solaris port.</li>
4067 <li>John Fleck helps maintaining the documentation and man pages.</li>
Daniel Veillard7b4b2f92003-01-06 13:11:20 +0000[diff] [blame]4068 <li><a href="mailto:igor@zlatkovic.com">Igor Zlatkovic</a> is now the
4069 maintainer of the Windows port, <a
4070 href="http://www.zlatkovic.com/projects/libxml/index.html">he provides
4071 binaries</a></li>
Daniel Veillardaf43f632002-03-08 15:05:20 +0000[diff] [blame]4072 <li><a href="mailto:Gary.Pennington@sun.com">Gary Pennington</a> provides
4073 <a href="http://garypennington.net/libxml2/">Solaris binaries</a></li>
Daniel Veillarde356c282001-03-10 12:32:04 +0000[diff] [blame]4074 <li><a
4075 href="http://mail.gnome.org/archives/xml/2001-March/msg00014.html">Matt
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]4076 Sergeant</a> developed <a
4077 href="http://axkit.org/download/">XML::LibXSLT</a>, a Perl wrapper for
Daniel Veillardaf43f632002-03-08 15:05:20 +0000[diff] [blame]4078 libxml2/libxslt as part of the <a href="http://axkit.com/">AxKit XML
4079 application server</a></li>
4080 <li><a href="mailto:fnatter@gmx.net">Felix Natter</a> and <a
4081 href="mailto:geertk@ai.rug.nl">Geert Kloosterman</a> provide <a
Daniel Veillardca989762001-06-23 17:39:29 +0000[diff] [blame]4082 href="libxml-doc.el">an emacs module</a> to lookup libxml(2) functions
Daniel Veillard3f6f7f62000-06-30 17:58:25 +0000[diff] [blame]4083 documentation</li>
Daniel Veillardaf43f632002-03-08 15:05:20 +0000[diff] [blame]4084 <li><a href="mailto:sherwin@nlm.nih.gov">Ziying Sherwin</a> provided <a
4085 href="http://xmlsoft.org/messages/0488.html">man pages</a></li>
Daniel Veillard5168dbf2001-07-07 00:18:23 +0000[diff] [blame]4086 <li>there is a module for <a
4087 href="http://acs-misc.sourceforge.net/nsxml.html">libxml/libxslt support
4088 in OpenNSD/AOLServer</a></li>
Daniel Veillard2d347fa2002-03-17 10:34:11 +0000[diff] [blame]4089 <li><a href="mailto:dkuhlman@cutter.rexx.com">Dave Kuhlman</a> provided the
4090 first version of libxml/libxslt <a
4091 href="http://www.rexx.com/~dkuhlman">wrappers for Python</a></li>
Daniel Veillard1aadc442001-11-28 13:10:32 +0000[diff] [blame]4092 <li>Petr Kozelka provides <a
4093 href="http://sourceforge.net/projects/libxml2-pas">Pascal units to glue
4094 libxml2</a> with Kylix and Delphi and other Pascal compilers</li>
Daniel Veillard2d347fa2002-03-17 10:34:11 +0000[diff] [blame]4095 <li><a href="mailto:aleksey@aleksey.com">Aleksey Sanin</a> implemented the
4096 <a href="http://www.w3.org/Signature/">XML Canonicalization and XML
4097 Digital Signature</a> <a
4098 href="http://www.aleksey.com/xmlsec/">implementations for libxml2</a></li>
Daniel Veillard17bed982003-02-24 20:11:43 +0000[diff] [blame]4099 <li><a href="mailto:Steve.Ball@zveno.com">Steve Ball</a>, <a
4100 href="http://www.zveno.com/">Zveno</a> and contributors maintain <a
4101 href="http://tclxml.sourceforge.net/">tcl bindings for libxml2 and
4102 libxslt</a>, as well as <a
4103 href="http://tclxml.sf.net/tkxmllint.html">tkxmllint</a> a GUI for
4104 xmllint and <a href="http://tclxml.sf.net/tkxsltproc.html">tkxsltproc</a>
4105 a GUI for xsltproc.</li>
Daniel Veillardc310d562000-06-23 18:32:15 +0000[diff] [blame]4106</ul>
4107
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]4108<p></p>
Daniel Veillardccb09631998-10-27 06:21:04 +0000[diff] [blame]4109</body>
4110</html>