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blob: ec30ec7dd9172b1601d848aa5fa00e23c8fa438b [file] [log] [blame]
Daniel Veillardccb09631998-10-27 06:21:04 +0000[diff] [blame]1<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]2 "http://www.w3.org/TR/REC-html40/loose.dtd">
Daniel Veillardccb09631998-10-27 06:21:04 +0000[diff] [blame]3<html>
4<head>
Daniel Veillardec78c0f2000-08-25 10:25:23 +0000[diff] [blame^]5 <title>The XML C library for Gnome</title>
6 <meta name="GENERATOR" content="amaya V3.2">
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 Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]11<p><a href="http://www.gnome.org/"><img src="smallfootonly.gif"
12alt="Gnome Logo"></a><a href="http://www.w3.org/Status"><img src="w3c.png"
13alt="W3C Logo"></a></p>
Daniel Veillardec303412000-03-24 13:41:54 +0000[diff] [blame]14
Daniel Veillardec78c0f2000-08-25 10:25:23 +0000[diff] [blame^]15<h1 align="center">The XML C library for Gnome</h1>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]16
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]17<h2 style="text-align: center">libxml, a.k.a. gnome-xml</h2>
18
19<p></p>
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]20<ul>
21 <li><a href="#Introducti">Introduction</a></li>
22 <li><a href="#Documentat">Documentation</a></li>
Daniel Veillard10a2c651999-12-12 13:03:50 +0000[diff] [blame]23 <li><a href="#Downloads">Downloads</a></li>
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]24 <li><a href="#News">News</a></li>
25 <li><a href="#XML">XML</a></li>
26 <li><a href="#tree">The tree output</a></li>
27 <li><a href="#interface">The SAX interface</a></li>
28 <li><a href="#library">The XML library interfaces</a>
29 <ul>
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]30 <li><a href="#Invoking">Invoking the parser: the pull way</a></li>
31 <li><a href="#Invoking">Invoking the parser: the push way</a></li>
32 <li><a href="#Invoking2">Invoking the parser: the SAX interface</a></li>
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]33 <li><a href="#Building">Building a tree from scratch</a></li>
34 <li><a href="#Traversing">Traversing the tree</a></li>
35 <li><a href="#Modifying">Modifying the tree</a></li>
36 <li><a href="#Saving">Saving the tree</a></li>
37 <li><a href="#Compressio">Compression</a></li>
38 </ul>
39 </li>
40 <li><a href="#Entities">Entities or no entities</a></li>
41 <li><a href="#Namespaces">Namespaces</a></li>
42 <li><a href="#Validation">Validation</a></li>
43 <li><a href="#Principles">DOM principles</a></li>
44 <li><a href="#real">A real example</a></li>
Daniel Veillardc310d562000-06-23 18:32:15 +0000[diff] [blame]45 <li><a href="#Contributi">Contribution</a></li>
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]46</ul>
47
48<h2><a name="Introducti">Introduction</a></h2>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]49
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]50<p>This document describes libxml, the <a
Daniel Veillardec78c0f2000-08-25 10:25:23 +0000[diff] [blame^]51href="http://www.w3.org/XML/">XML</a> C library developped for the <a
52href="http://www.gnome.org/">Gnome</a> project. <a
53href="http://www.w3.org/XML/">XML is a standard</a> for building tag-based
54structured documents/data.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]55
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]56<p>Here are some key points about libxml:</p>
57<ul>
Daniel Veillardec78c0f2000-08-25 10:25:23 +0000[diff] [blame^]58 <li>It is written in plain C, making as few assumptions as possible, and
Daniel Veillard6f0adb52000-07-03 11:41:26 +0000[diff] [blame]59 sticking closely to ANSI C for easy embedding.</li>
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]60 <li>The internal document repesentation is as close as possible to the <a
61 href="http://www.w3.org/DOM/">DOM</a> interfaces.</li>
62 <li>Libxml also has a <a href="http://www.megginson.com/SAX/index.html">SAX
Daniel Veillard402e8c82000-02-29 22:57:47 +0000[diff] [blame]63 like interface</a>; the interface is designed to be compatible with <a
64 href="http://www.jclark.com/xml/expat.html">Expat</a>.</li>
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]65 <li>Libxml now includes a nearly complete <a
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]66 href="http://www.w3.org/TR/xpath">XPath</a> implementation.</li>
Daniel Veillard402e8c82000-02-29 22:57:47 +0000[diff] [blame]67 <li>Libxml exports Push and Pull type parser interfaces for both XML and
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]68 HTML.</li>
Daniel Veillardec303412000-03-24 13:41:54 +0000[diff] [blame]69 <li>This library is released both under the <a
70 href="http://www.w3.org/Consortium/Legal/copyright-software-19980720.html">W3C
71 IPR</a> and the GNU LGPL. Use either at your convenience, basically this
72 should make everybody happy, if not, drop me a mail.</li>
Daniel Veillardc310d562000-06-23 18:32:15 +0000[diff] [blame]73 <li>There is <a href="upgrade.html">a first set of instructions</a>
Daniel Veillardedfb29b2000-03-14 19:59:05 +0000[diff] [blame]74 concerning upgrade from libxml-1.x to libxml-2.x</li>
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]75</ul>
Daniel Veillardccb09631998-10-27 06:21:04 +0000[diff] [blame]76
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]77<h2><a name="Documentat">Documentation</a></h2>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]78
Daniel Veillard402e8c82000-02-29 22:57:47 +0000[diff] [blame]79<p>There are some on-line resources about using libxml:</p>
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]80<ol>
Daniel Veillard365e13b2000-07-02 07:56:37 +0000[diff] [blame]81 <li>Check the <a href="FAQ.html">FAQ</a></li>
Daniel Veillardc19fccc2000-07-03 11:52:01 +0000[diff] [blame]82 <li>Check the <a href="http://xmlsoft.org/html/libxml-lib.html">extensive
Daniel Veillard365e13b2000-07-02 07:56:37 +0000[diff] [blame]83 documentation</a> automatically extracted from code comments.</li>
Daniel Veillard8d869642000-07-14 12:12:59 +0000[diff] [blame]84 <li>Look at the documentation about <a href="encoding.html">libxml
85 internationalization support</a></li>
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]86 <li>This page provides a global overview and <a href="#real">some
Daniel Veillard402e8c82000-02-29 22:57:47 +0000[diff] [blame]87 examples</a> on how to use libxml.</li>
88 <li><a href="mailto:james@daa.com.au">James Henstridge</a> wrote <a
89 href="http://www.daa.com.au/~james/gnome/xml-sax/xml-sax.html">some nice
90 documentation</a> explaining how to use the libxml SAX interface.</li>
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]91 <li>George Lebl wrote <a
92 href="http://www-4.ibm.com/software/developer/library/gnome3/">an article
Daniel Veillard402e8c82000-02-29 22:57:47 +0000[diff] [blame]93 for IBM developerWorks</a> about using libxml.</li>
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]94 <li>It is also a good idea to check to <a href="mailto:raph@levien.com">Raph
95 Levien</a> <a href="http://levien.com/gnome/">web site</a> since he is
96 building the <a href="http://levien.com/gnome/gdome.html">DOM interface
Daniel Veillard402e8c82000-02-29 22:57:47 +0000[diff] [blame]97 gdome</a> on top of libxml result tree and an implementation of <a
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]98 href="http://www.w3.org/Graphics/SVG/">SVG</a> called <a
99 href="http://www.levien.com/svg/">gill</a>. Check his <a
100 href="http://www.levien.com/gnome/domination.html">DOMination
101 paper</a>.</li>
Daniel Veillardec303412000-03-24 13:41:54 +0000[diff] [blame]102 <li>Check <a href="http://cvs.gnome.org/lxr/source/gnome-xml/TODO">the TODO
103 file</a></li>
104 <li>Read the <a href="upgrade.html">1.x to 2.x upgrade path</a>. If you are
105 starting a new project using libxml you should really use the 2.x
106 version.</li>
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]107 <li>And don't forget to look at the <a href="/messages/">mailing-list
Daniel Veillardc310d562000-06-23 18:32:15 +0000[diff] [blame]108 archive</a>.</li>
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]109</ol>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]110
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]111<h3>Reporting bugs and getting help</h3>
Daniel Veillard4c3a2031999-11-19 17:46:26 +0000[diff] [blame]112
Daniel Veillard402e8c82000-02-29 22:57:47 +0000[diff] [blame]113<p>Well, bugs or missing features are always possible, and I will make a point
114of fixing them in a timely fashion. The best way to report a bug is to <a
Daniel Veillard4c3a2031999-11-19 17:46:26 +0000[diff] [blame]115href="http://bugs.gnome.org/db/pa/lgnome-xml.html">use the Gnome bug tracking
Daniel Veillard402e8c82000-02-29 22:57:47 +0000[diff] [blame]116database</a>. I look at reports there regularly and it's good to have a
Daniel Veillard4c3a2031999-11-19 17:46:26 +0000[diff] [blame]117reminder when a bug is still open. Check the <a
118href="http://bugs.gnome.org/Reporting.html">instructions on reporting bugs</a>
Daniel Veillard402e8c82000-02-29 22:57:47 +0000[diff] [blame]119and be sure to specify that the bug is for the package gnome-xml.</p>
Daniel Veillard4c3a2031999-11-19 17:46:26 +0000[diff] [blame]120
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]121<p>There is also a mailing-list <a
122href="mailto:xml@rufus.w3.org">xml@rufus.w3.org</a> for libxml, with an <a
123href="http://xmlsoft.org/messages">on-line archive</a>. To subscribe to this
Daniel Veillard402e8c82000-02-29 22:57:47 +0000[diff] [blame]124majordomo based list, send a mail message to <a
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]125href="mailto:majordomo@rufus.w3.org">majordomo@rufus.w3.org</a> with
126"subscribe xml" in the <strong>content</strong> of the message.</p>
127
Daniel Veillard402e8c82000-02-29 22:57:47 +0000[diff] [blame]128<p>Alternatively, you can just send the bug to the <a
Daniel Veillard10a2c651999-12-12 13:03:50 +0000[diff] [blame]129href="mailto:xml@rufus.w3.org">xml@rufus.w3.org</a> list.</p>
Daniel Veillard4c3a2031999-11-19 17:46:26 +0000[diff] [blame]130
Daniel Veillardec303412000-03-24 13:41:54 +0000[diff] [blame]131<p>Of course, bugs reports with a suggested patch for fixing them will
132probably be processed faster.</p>
133
134<p>If you're looking for help, a quick look at <a
135href="http://xmlsoft.org/messages/#407">the list archive</a> may actually
136provide the answer, I usually send source samples when answering libxml usage
Daniel Veillard6f0adb52000-07-03 11:41:26 +0000[diff] [blame]137questions. The <a href="http://xmlsoft.org/html/book1.html">auto-generated
Daniel Veillardec303412000-03-24 13:41:54 +0000[diff] [blame]138documentantion</a> is not as polished as I would like (i need to learn more
139about Docbook), but it's a good starting point.</p>
140
Daniel Veillard10a2c651999-12-12 13:03:50 +0000[diff] [blame]141<h2><a name="Downloads">Downloads</a></h2>
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]142
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]143<p>The latest versions of libxml can be found on <a
Daniel Veillard6c8b1172000-03-01 00:40:41 +0000[diff] [blame]144href="ftp://rpmfind.net/pub/libxml/">rpmfind.net</a> or on the <a
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]145href="ftp://ftp.gnome.org/pub/GNOME/MIRRORS.html">Gnome FTP server</a> either
Daniel Veillard10a2c651999-12-12 13:03:50 +0000[diff] [blame]146as a <a href="ftp://ftp.gnome.org/pub/GNOME/stable/sources/libxml/">source
Daniel Veillard306be992000-07-03 12:38:45 +0000[diff] [blame]147archive</a> or <a
148href="ftp://ftp.gnome.org/pub/GNOME/contrib/redhat/SRPMS/">RPM packages</a>.
149(NOTE that you need both the <a
Daniel Veillardc19fccc2000-07-03 11:52:01 +0000[diff] [blame]150href="http://rpmfind.net/linux/RPM/libxml2.html">libxml(2)</a> and <a
151href="http://rpmfind.net/linux/RPM/libxml2-devel.html">libxml(2)-devel</a>
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]152packages installed to compile applications using libxml.)</p>
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]153
Daniel Veillard6c8b1172000-03-01 00:40:41 +0000[diff] [blame]154<p><a name="Snapshot">Snapshot:</a></p>
155<ul>
156 <li>Code from the W3C cvs base libxml <a
157 href="ftp://rpmfind.net/pub/libxml/cvs-snapshot.tar.gz">cvs-snapshot.tar.gz</a></li>
158 <li>Docs, content of the web site, the list archive included <a
159 href="ftp://rpmfind.net/pub/libxml/libxml-docs.tar.gz">libxml-docs.tar.gz</a></li>
160</ul>
161
162<p><a name="Contribs">Contribs:</a></p>
163
164<p>I do accept external contributions, especially if compiling on another
165platform, get in touch with me to upload the package. I will keep them in the
166<a href="ftp://rpmfind.net/pub/libxml/contribs/">contrib directory</a></p>
167
Daniel Veillardc310d562000-06-23 18:32:15 +0000[diff] [blame]168<p>Libxml is also available from 2 CVS bases:</p>
Daniel Veillard10a2c651999-12-12 13:03:50 +0000[diff] [blame]169<ul>
170 <li><p>The <a href="http://dev.w3.org/cvsweb/XML/">W3C CVS base</a>,
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]171 available read-only using the CVS pserver authentification (I tend to use
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]172 this base for my own development, so it's updated more regularly, but the
173 content may not be as stable):</p>
Daniel Veillard10a2c651999-12-12 13:03:50 +0000[diff] [blame]174 <pre>CVSROOT=:pserver:anonymous@dev.w3.org:/sources/public
Daniel Veillard365e13b2000-07-02 07:56:37 +0000[diff] [blame]175 password: anonymous
176 module: XML</pre>
Daniel Veillard10a2c651999-12-12 13:03:50 +0000[diff] [blame]177 </li>
178 <li><p>The <a
179 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]180 CVS base</a>. Check the <a
181 href="http://developer.gnome.org/tools/cvs.html">Gnome CVS Tools</a> page;
182 the CVS module is <b>gnome-xml</b>.</p>
Daniel Veillard10a2c651999-12-12 13:03:50 +0000[diff] [blame]183 </li>
184</ul>
185
186<h2><a name="News">News</a></h2>
187
Daniel Veillard944b5ff1999-12-15 19:08:24 +0000[diff] [blame]188<h3>CVS only : check the <a
189href="http://cvs.gnome.org/lxr/source/gnome-xml/ChangeLog">Changelog</a> file
190for really accurate description</h3>
Daniel Veillard4c3a2031999-11-19 17:46:26 +0000[diff] [blame]191<ul>
Daniel Veillard10a2c651999-12-12 13:03:50 +0000[diff] [blame]192 <li>working on HTML and XML links recognition layers, get in touch with me
Daniel Veillard944b5ff1999-12-15 19:08:24 +0000[diff] [blame]193 if you want to test those.</li>
Daniel Veillard361d8452000-04-03 19:48:13 +0000[diff] [blame]194</ul>
195
Daniel Veillard786d7c82000-08-12 23:38:57 +0000[diff] [blame]196<h2>2.2.2: August 12 2000</h2>
197<ul>
198 <li>mostly bug fixes</li>
Daniel Veillardec78c0f2000-08-25 10:25:23 +0000[diff] [blame^]199 <li>started adding routines to access xml parser context options</li>
Daniel Veillard786d7c82000-08-12 23:38:57 +0000[diff] [blame]200</ul>
201
Daniel Veillarda2679fa2000-07-22 02:38:15 +0000[diff] [blame]202<h2>2.2.1: July 21 2000</h2>
203<ul>
204 <li>a purely bug fixes release</li>
205 <li>fixed an encoding support problem when parsing from a memory block</li>
206 <li>fixed a DOCTYPE parsing problem</li>
207 <li>removed a bug in the function allowing to override the memory allocation
208 routines</li>
209</ul>
210
Daniel Veillard94e90602000-07-17 14:38:19 +0000[diff] [blame]211<h2>2.2.0: July 14 2000</h2>
212<ul>
213 <li>applied a lot of portability fixes</li>
214 <li>better encoding support/cleanup and saving (content is now always
215 encoded in UTF-8)</li>
216 <li>the HTML parser now correctly handles encodings</li>
217 <li>added xmlHasProp()</li>
218 <li>fixed a serious problem with &amp;#38;</li>
219 <li>propagated the fix to FTP client</li>
220 <li>cleanup, bugfixes, etc ...</li>
221 <li>Added a page about <a href="encoding.html">libxml Internationalization
222 support</a></li>
223</ul>
224
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]225<h3>1.8.9: July 9 2000</h3>
226<ul>
227 <li>fixed the spec the RPMs should be better</li>
228 <li>fixed a serious bug in the FTP implementation, released 1.8.9 to solve
229 rpmfind users problem</li>
230</ul>
231
Daniel Veillard6388e172000-07-03 16:07:19 +0000[diff] [blame]232<h3>2.1.1: July 1 2000</h3>
233<ul>
234 <li>fixes a couple of bugs in the 2.1.0 packaging</li>
235 <li>improvements on the HTML parser</li>
236</ul>
237
Daniel Veillard3f6f7f62000-06-30 17:58:25 +0000[diff] [blame]238<h3>2.1.0 and 1.8.8: June 29 2000</h3>
239<ul>
240 <li>1.8.8 is mostly a comodity package for upgrading to libxml2 accoding to
241 <a href="upgrade.html">new instructions</a>. It fixes a nasty problem
242 about &amp;#38; charref parsing</li>
243 <li>2.1.0 also ease the upgrade from libxml v1 to the recent version. it
244 also contains numerous fixes and enhancements:
245 <ul>
246 <li>added xmlStopParser() to stop parsing</li>
247 <li>improved a lot parsing speed when there is large CDATA blocs</li>
248 <li>includes XPath patches provided by Picdar Technology</li>
249 <li>tried to fix as much as possible DtD validation and namespace
250 related problems</li>
251 <li>output to a given encoding has been added/tested</li>
252 <li>lot of various fixes</li>
253 </ul>
254 </li>
255</ul>
256
Daniel Veillarde0aed302000-04-16 08:52:20 +0000[diff] [blame]257<h3>2.0.0: Apr 12 2000</h3>
Daniel Veillard361d8452000-04-03 19:48:13 +0000[diff] [blame]258<ul>
259 <li>First public release of libxml2. If you are using libxml, it's a good
Daniel Veillarde0aed302000-04-16 08:52:20 +0000[diff] [blame]260 idea to check the 1.x to 2.x upgrade instructions. NOTE: while initally
261 scheduled for Apr 3 the relase occured only on Apr 12 due to massive
262 workload.</li>
Daniel Veillard361d8452000-04-03 19:48:13 +0000[diff] [blame]263 <li>The include are now located under $prefix/include/libxml (instead of
Daniel Veillarde0aed302000-04-16 08:52:20 +0000[diff] [blame]264 $prefix/include/gnome-xml), they also are referenced by
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]265 <pre>#include &lt;libxml/xxx.h&gt;</pre>
Daniel Veillarde0aed302000-04-16 08:52:20 +0000[diff] [blame]266 <p>instead of</p>
Daniel Veillard361d8452000-04-03 19:48:13 +0000[diff] [blame]267 <pre>#include "xxx.h"</pre>
268 </li>
Daniel Veillard8f621982000-03-20 13:07:15 +0000[diff] [blame]269 <li>a new URI module for parsing URIs and following strictly RFC 2396</li>
270 <li>the memory allocation routines used by libxml can now be overloaded
271 dynamically by using xmlMemSetup()</li>
Daniel Veillard361d8452000-04-03 19:48:13 +0000[diff] [blame]272 <li>The previously CVS only tool tester has been renamed
273 <strong>xmllint</strong> and is now installed as part of the libxml2
274 package</li>
Daniel Veillarde0aed302000-04-16 08:52:20 +0000[diff] [blame]275 <li>The I/O interface has been revamped. There is now ways to plug in
276 specific I/O modules, either at the URI scheme detection level using
277 xmlRegisterInputCallbacks() or by passing I/O functions when creating a
278 parser context using xmlCreateIOParserCtxt()</li>
279 <li>there is a C preprocessor macro LIBXML_VERSION providing the version
280 number of the libxml module in use</li>
281 <li>a number of optional features of libxml can now be excluded at configure
282 time (FTP/HTTP/HTML/XPath/Debug)</li>
Daniel Veillardedfb29b2000-03-14 19:59:05 +0000[diff] [blame]283</ul>
284
285<h3>2.0.0beta: Mar 14 2000</h3>
286<ul>
287 <li>This is a first Beta release of libxml version 2</li>
288 <li>It's available only from<a href="ftp://rpmfind.net/pub/libxml/">
289 rpmfind.net FTP</a>, it's packaged as libxml2-2.0.0beta and available as
290 tar and RPMs</li>
291 <li>This version is now the head in the Gnome CVS base, the old one is
292 available under the tag LIB_XML_1_X</li>
293 <li>This includes a very large set of changes. Froma programmatic point of
294 view applications should not have to be modified too much, check the <a
295 href="upgrade.html">upgrade page</a></li>
296 <li>Some interfaces may changes (especially a bit about encoding).</li>
297 <li>the updates includes:
Daniel Veillard6c8b1172000-03-01 00:40:41 +0000[diff] [blame]298 <ul>
Daniel Veillardedfb29b2000-03-14 19:59:05 +0000[diff] [blame]299 <li>fix I18N support. ISO-Latin-x/UTF-8/UTF-16 (nearly) seems correctly
300 handled now</li>
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]301 <li>Better handling of entities, especially well formedness checking and
302 proper PEref extensions in external subsets</li>
Daniel Veillard6c8b1172000-03-01 00:40:41 +0000[diff] [blame]303 <li>DTD conditional sections</li>
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]304 <li>Validation now correcly handle entities content</li>
Daniel Veillard6c8b1172000-03-01 00:40:41 +0000[diff] [blame]305 <li><a href="http://rpmfind.net/tools/gdome/messages/0039.html">change
306 structures to accomodate DOM</a></li>
Daniel Veillard6c8b1172000-03-01 00:40:41 +0000[diff] [blame]307 </ul>
308 </li>
Daniel Veillardedfb29b2000-03-14 19:59:05 +0000[diff] [blame]309 <li>Serious progress were made toward compliance, <a
310 href="conf/result.html">here are the result of the test</a> against the
311 OASIS testsuite (except the japanese tests since I don't support that
312 encoding yet). This URL is rebuilt every couple of hours using the CVS
313 head version.</li>
Daniel Veillarde41f2b72000-01-30 20:00:07 +0000[diff] [blame]314</ul>
315
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]316<h3>1.8.7: Mar 6 2000</h3>
317<ul>
318 <li>This is a bug fix release:</li>
319 <li>It is possible to disable the ignorable blanks heuristic used by
320 libxml-1.x, a new function xmlKeepBlanksDefault(0) will allow this. Note
321 that for adherence to XML spec, this behaviour will be disabled by default
322 in 2.x . The same function will allow to keep compatibility for old
323 code.</li>
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]324 <li>Blanks in &lt;a&gt; &lt;/a&gt; constructs are not ignored anymore,
325 avoiding heuristic is really the Right Way :-\</li>
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]326 <li>The unchecked use of snprintf which was breaking libxml-1.8.6
327 compilation on some platforms has been fixed</li>
328 <li>nanoftp.c nanohttp.c: Fixed '#' and '?' stripping when processing
329 URIs</li>
330</ul>
331
Daniel Veillarde41f2b72000-01-30 20:00:07 +0000[diff] [blame]332<h3>1.8.6: Jan 31 2000</h3>
333<ul>
334 <li>added a nanoFTP transport module, debugged until the new version of <a
335 href="http://rpmfind.net/linux/rpm2html/rpmfind.html">rpmfind</a> can use
336 it without troubles</li>
Daniel Veillardda07c342000-01-25 18:31:22 +0000[diff] [blame]337</ul>
338
339<h3>1.8.5: Jan 21 2000</h3>
340<ul>
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]341 <li>adding APIs to parse a well balanced chunk of XML (production <a
342 href="http://www.w3.org/TR/REC-xml#NT-content">[43] content</a> of the XML
343 spec)</li>
Daniel Veillard461a66c2000-01-18 18:01:01 +0000[diff] [blame]344 <li>fixed a hideous bug in xmlGetProp pointed by Rune.Djurhuus@fast.no</li>
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]345 <li>Jody Goldberg &lt;jgoldberg@home.com&gt; provided another patch trying
346 to solve the zlib checks problems</li>
Daniel Veillard461a66c2000-01-18 18:01:01 +0000[diff] [blame]347 <li>The current state in gnome CVS base is expected to ship as 1.8.5 with
348 gnumeric soon</li>
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]349</ul>
350
351<h3>1.8.4: Jan 13 2000</h3>
352<ul>
353 <li>bug fixes, reintroduced xmlNewGlobalNs(), fixed xmlNewNs()</li>
354 <li>all exit() call should have been removed from libxml</li>
355 <li>fixed a problem with INCLUDE_WINSOCK on WIN32 platform</li>
356 <li>added newDocFragment()</li>
Daniel Veillardf84f71f2000-01-05 19:54:23 +0000[diff] [blame]357</ul>
358
359<h3>1.8.3: Jan 5 2000</h3>
360<ul>
361 <li>a Push interface for the XML and HTML parsers</li>
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]362 <li>a shell-like interface to the document tree (try tester --shell :-)</li>
Daniel Veillarddbfd6411999-12-28 16:35:14 +0000[diff] [blame]363 <li>lots of bug fixes and improvement added over XMas hollidays</li>
Daniel Veillard437b87b2000-01-03 17:30:46 +0000[diff] [blame]364 <li>fixed the DTD parsing code to work with the xhtml DTD</li>
Daniel Veillardf84f71f2000-01-05 19:54:23 +0000[diff] [blame]365 <li>added xmlRemoveProp(), xmlRemoveID() and xmlRemoveRef()</li>
366 <li>Fixed bugs in xmlNewNs()</li>
Daniel Veillard437b87b2000-01-03 17:30:46 +0000[diff] [blame]367 <li>External entity loading code has been revamped, now it uses
Daniel Veillardf84f71f2000-01-05 19:54:23 +0000[diff] [blame]368 xmlLoadExternalEntity(), some fix on entities processing were added</li>
Daniel Veillard437b87b2000-01-03 17:30:46 +0000[diff] [blame]369 <li>cleaned up WIN32 includes of socket stuff</li>
Daniel Veillard5cb5ab81999-12-21 15:35:29 +0000[diff] [blame]370</ul>
371
372<h3>1.8.2: Dec 21 1999</h3>
373<ul>
Daniel Veillardb24054a1999-12-18 15:32:46 +0000[diff] [blame]374 <li>I got another problem with includes and C++, I hope this issue is fixed
375 for good this time</li>
Daniel Veillard5cb5ab81999-12-21 15:35:29 +0000[diff] [blame]376 <li>Added a few tree modification functions: xmlReplaceNode,
377 xmlAddPrevSibling, xmlAddNextSibling, xmlNodeSetName and
378 xmlDocSetRootElement</li>
379 <li>Tried to improve the HTML output with help from <a
380 href="mailto:clahey@umich.edu">Chris Lahey</a></li>
Daniel Veillarde4e51311999-12-18 15:32:46 +0000[diff] [blame]381</ul>
Daniel Veillardb24054a1999-12-18 15:32:46 +0000[diff] [blame]382
Daniel Veillarde4e51311999-12-18 15:32:46 +0000[diff] [blame]383<h3>1.8.1: Dec 18 1999</h3>
384<ul>
385 <li>various patches to avoid troubles when using libxml with C++ compilers
386 the "namespace" keyword and C escaping in include files</li>
387 <li>a problem in one of the core macros IS_CHAR was corrected</li>
388 <li>fixed a bug introduced in 1.8.0 breaking default namespace processing,
389 and more specifically the Dia application</li>
Daniel Veillard944b5ff1999-12-15 19:08:24 +0000[diff] [blame]390 <li>fixed a posteriori validation (validation after parsing, or by using a
391 Dtd not specified in the original document)</li>
Daniel Veillardb24054a1999-12-18 15:32:46 +0000[diff] [blame]392 <li>fixed a bug in</li>
Daniel Veillard10a2c651999-12-12 13:03:50 +0000[diff] [blame]393</ul>
394
395<h3>1.8.0: Dec 12 1999</h3>
396<ul>
397 <li>cleanup, especially memory wise</li>
398 <li>the parser should be more reliable, especially the HTML one, it should
399 not crash, whatever the input !</li>
400 <li>Integrated various patches, especially a speedup improvement for large
401 dataset from <a href="mailto:cnygard@bellatlantic.net">Carl Nygard</a>,
402 configure with --with-buffers to enable them.</li>
403 <li>attribute normalization, oops should have been added long ago !</li>
404 <li>attributes defaulted from Dtds should be available, xmlSetProp() now
405 does entities escapting by default.</li>
Daniel Veillard4c3a2031999-11-19 17:46:26 +0000[diff] [blame]406</ul>
Daniel Veillard35008381999-10-25 13:15:52 +0000[diff] [blame]407
408<h3>1.7.4: Oct 25 1999</h3>
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]409<ul>
Daniel Veillard35008381999-10-25 13:15:52 +0000[diff] [blame]410 <li>Lots of HTML improvement</li>
411 <li>Fixed some errors when saving both XML and HTML</li>
412 <li>More examples, the regression tests should now look clean</li>
413 <li>Fixed a bug with contiguous charref</li>
414</ul>
415
416<h3>1.7.3: Sep 29 1999</h3>
417<ul>
418 <li>portability problems fixed</li>
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]419 <li>snprintf was used unconditionnally, leading to link problems on system
Daniel Veillard35008381999-10-25 13:15:52 +0000[diff] [blame]420 were it's not available, fixed</li>
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]421</ul>
422
423<h3>1.7.1: Sep 24 1999</h3>
424<ul>
425 <li>The basic type for strings manipulated by libxml has been renamed in
426 1.7.1 from <strong>CHAR</strong> to <strong>xmlChar</strong>. The reason
427 is that CHAR was conflicting with a predefined type on Windows. However on
428 non WIN32 environment, compatibility is provided by the way of a
429 <strong>#define </strong>.</li>
430 <li>Changed another error : the use of a structure field called errno, and
431 leading to troubles on platforms where it's a macro</li>
432</ul>
433
434<h3>1.7.0: sep 23 1999</h3>
435<ul>
436 <li>Added the ability to fetch remote DTD or parsed entities, see the <a
Daniel Veillardc19fccc2000-07-03 11:52:01 +0000[diff] [blame]437 href="html/gnome-xml-nanohttp.html">nanohttp</a> module.</li>
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]438 <li>Added an errno to report errors by another mean than a simple printf
439 like callback</li>
440 <li>Finished ID/IDREF support and checking when validation</li>
441 <li>Serious memory leaks fixed (there is now a <a
Daniel Veillardc19fccc2000-07-03 11:52:01 +0000[diff] [blame]442 href="html/gnome-xml-xmlmemory.html">memory wrapper</a> module)</li>
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]443 <li>Improvement of <a href="http://www.w3.org/TR/xpath">XPath</a>
444 implementation</li>
445 <li>Added an HTML parser front-end</li>
446</ul>
447
448<h2><a name="XML">XML</a></h2>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]449
Daniel Veillard402e8c82000-02-29 22:57:47 +0000[diff] [blame]450<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]451markup-based structured documents. Here is <a name="example">an example XML
452document</a>:</p>
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]453<pre>&lt;?xml version="1.0"?&gt;
454&lt;EXAMPLE prop1="gnome is great" prop2="&amp;amp; linux too"&gt;
455 &lt;head&gt;
456 &lt;title&gt;Welcome to Gnome&lt;/title&gt;
457 &lt;/head&gt;
458 &lt;chapter&gt;
459 &lt;title&gt;The Linux adventure&lt;/title&gt;
460 &lt;p&gt;bla bla bla ...&lt;/p&gt;
461 &lt;image href="linus.gif"/&gt;
462 &lt;p&gt;...&lt;/p&gt;
463 &lt;/chapter&gt;
464&lt;/EXAMPLE&gt;</pre>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]465
Daniel Veillard402e8c82000-02-29 22:57:47 +0000[diff] [blame]466<p>The first line specifies that it's an XML document and gives useful
467information about its encoding. Then the document is a text format whose
468structure is specified by tags between brackets. <strong>Each tag opened has
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]469to be closed</strong>. XML is pedantic about this. However, if a tag is empty
470(no content), a single tag can serve as both the opening and closing tag if it
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]471ends with <code>/&gt;</code> rather than with <code>&gt;</code>. Note that,
472for example, the image tag has no content (just an attribute) and is closed by
473ending the tag with <code>/&gt;</code>.</p>
Daniel Veillardccb09631998-10-27 06:21:04 +0000[diff] [blame]474
Daniel Veillard402e8c82000-02-29 22:57:47 +0000[diff] [blame]475<p>XML can be applied sucessfully to a wide range of uses, from long term
476structured document maintenance (where it follows the steps of SGML) to simple
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]477data encoding mechanisms like configuration file formatting (glade),
478spreadsheets (gnumeric), or even shorter lived documents such as WebDAV where
479it is used to encode remote calls between a client and a server.</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]480
Daniel Veillard4540be42000-08-19 16:40:28 +0000[diff] [blame]481<h2>An overview of libxml architecture</h2>
482
483<p>Libxml is made of multiple components, some of them optionals, and most of
484the block interfaces are public. The main components are:</p>
485<ul>
486 <li>an Input/Output layer</li>
487 <li>FTP and HTTP client layers (optionnal)</li>
488 <li>an Internationalization layer managing the encodings support</li>
489 <li>an URI module</li>
490 <li>the XML parser and its basic SAX interface</li>
491 <li>an HTML parser using the same SAX interface (optionnal)</li>
492 <li>a SAX tree module to build an in-memory DOM representation</li>
493 <li>a tree module to manipulate the DOM representation</li>
494 <li>a validation module using the DOM representation (optionnal)</li>
495 <li>an XPath module for global lookup in a DOM representation
496 (optionnal)</li>
497 <li>a debug module (optionnal)</li>
498</ul>
499
500<p>Graphically this gives the following:</p>
501
502<p><img src="libxml.gif" alt="a graphical view of the various"></p>
503
504<p></p>
505
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]506<h2><a name="tree">The tree output</a></h2>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]507
508<p>The parser returns a tree built during the document analysis. The value
Daniel Veillard402e8c82000-02-29 22:57:47 +0000[diff] [blame]509returned is an <strong>xmlDocPtr</strong> (i.e., a pointer to an
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]510<strong>xmlDoc</strong> structure). This structure contains information such
Daniel Veillard306be992000-07-03 12:38:45 +0000[diff] [blame]511as the file name, the document type, and a <strong>children</strong> pointer
512which is the root of the document (or more exactly the first child under the
513root which is the document). The tree is made of <strong>xmlNode</strong>s,
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]514chained in double-linked lists of siblings and with children&lt;-&gt;parent
Daniel Veillard306be992000-07-03 12:38:45 +0000[diff] [blame]515relationship. An xmlNode can also carry properties (a chain of xmlAttr
516structures). An attribute may have a value which is a list of TEXT or
517ENTITY_REF nodes.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]518
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]519<p>Here is an example (erroneous with respect to the XML spec since there
520should be only one ELEMENT under the root):</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]521
522<p><img src="structure.gif" alt=" structure.gif "></p>
523
524<p>In the source package there is a small program (not installed by default)
Daniel Veillard361d8452000-04-03 19:48:13 +0000[diff] [blame]525called <strong>xmllint</strong> which parses XML files given as argument and
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]526prints them back as parsed. This is useful for detecting errors both in XML
527code and in the XML parser itself. It has an option <strong>--debug</strong>
528which prints the actual in-memory structure of the document, here is the
529result with the <a href="#example">example</a> given before:</p>
Daniel Veillard10c6a8f1998-10-28 01:00:12 +0000[diff] [blame]530<pre>DOCUMENT
531version=1.0
532standalone=true
533 ELEMENT EXAMPLE
534 ATTRIBUTE prop1
535 TEXT
536 content=gnome is great
537 ATTRIBUTE prop2
538 ENTITY_REF
539 TEXT
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]540 content= linux too
Daniel Veillard402e8c82000-02-29 22:57:47 +0000[diff] [blame]541 ELEMENT head
Daniel Veillard10c6a8f1998-10-28 01:00:12 +0000[diff] [blame]542 ELEMENT title
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]543 TEXT
544 content=Welcome to Gnome
Daniel Veillard10c6a8f1998-10-28 01:00:12 +0000[diff] [blame]545 ELEMENT chapter
546 ELEMENT title
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]547 TEXT
548 content=The Linux adventure
Daniel Veillard10c6a8f1998-10-28 01:00:12 +0000[diff] [blame]549 ELEMENT p
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]550 TEXT
551 content=bla bla bla ...
Daniel Veillard10c6a8f1998-10-28 01:00:12 +0000[diff] [blame]552 ELEMENT image
553 ATTRIBUTE href
554 TEXT
555 content=linus.gif
556 ELEMENT p
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]557 TEXT
558 content=...</pre>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]559
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]560<p>This should be useful for learning the internal representation model.</p>
Daniel Veillardccb09631998-10-27 06:21:04 +0000[diff] [blame]561
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]562<h2><a name="interface">The SAX interface</a></h2>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]563
Daniel Veillard402e8c82000-02-29 22:57:47 +0000[diff] [blame]564<p>Sometimes the DOM tree output is just too large to fit reasonably into
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]565memory. In that case (and if you don't expect to save back the XML document
566loaded using libxml), it's better to use the SAX interface of libxml. SAX is a
Daniel Veillard402e8c82000-02-29 22:57:47 +0000[diff] [blame]567<strong>callback-based interface</strong> to the parser. Before parsing, the
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]568application layer registers a customized set of callbacks which are called by
569the library as it progresses through the XML input.</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]570
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]571<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]572libxml, see the <a
573href="http://www.daa.com.au/~james/gnome/xml-sax/xml-sax.html">nice
574documentation</a>.written by <a href="mailto:james@daa.com.au">James
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]575Henstridge</a>.</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]576
577<p>You can debug the SAX behaviour by using the <strong>testSAX</strong>
578program located in the gnome-xml module (it's usually not shipped in the
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]579binary packages of libxml, but you can find it in the tar source
Daniel Veillard402e8c82000-02-29 22:57:47 +0000[diff] [blame]580distribution). Here is the sequence of callbacks that would be reported by
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]581testSAX when parsing the example XML document shown earlier:</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]582<pre>SAX.setDocumentLocator()
583SAX.startDocument()
584SAX.getEntity(amp)
585SAX.startElement(EXAMPLE, prop1='gnome is great', prop2='&amp;amp; linux too')
586SAX.characters( , 3)
587SAX.startElement(head)
588SAX.characters( , 4)
589SAX.startElement(title)
590SAX.characters(Welcome to Gnome, 16)
591SAX.endElement(title)
592SAX.characters( , 3)
593SAX.endElement(head)
594SAX.characters( , 3)
595SAX.startElement(chapter)
596SAX.characters( , 4)
597SAX.startElement(title)
598SAX.characters(The Linux adventure, 19)
599SAX.endElement(title)
600SAX.characters( , 4)
601SAX.startElement(p)
602SAX.characters(bla bla bla ..., 15)
603SAX.endElement(p)
604SAX.characters( , 4)
605SAX.startElement(image, href='linus.gif')
606SAX.endElement(image)
607SAX.characters( , 4)
608SAX.startElement(p)
609SAX.characters(..., 3)
610SAX.endElement(p)
611SAX.characters( , 3)
612SAX.endElement(chapter)
613SAX.characters( , 1)
614SAX.endElement(EXAMPLE)
615SAX.endDocument()</pre>
616
Daniel Veillard402e8c82000-02-29 22:57:47 +0000[diff] [blame]617<p>Most of the other functionalities of libxml are based on the DOM
618tree-building facility, so nearly everything up to the end of this document
619presupposes the use of the standard DOM tree build. Note that the DOM tree
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]620itself is built by a set of registered default callbacks, without internal
621specific interface.</p>
622
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]623<h2><a name="library">The XML library interfaces</a></h2>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]624
625<p>This section is directly intended to help programmers getting bootstrapped
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]626using the XML library from the C language. It is not intended to be extensive.
627I hope the automatically generated documents will provide the completeness
628required, but as a separate set of documents. The interfaces of the XML
629library are by principle low level, there is nearly zero abstraction. Those
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]630interested in a higher level API should <a href="#DOM">look at DOM</a>.</p>
Daniel Veillardccb09631998-10-27 06:21:04 +0000[diff] [blame]631
Daniel Veillardc19fccc2000-07-03 11:52:01 +0000[diff] [blame]632<p>The <a href="html/gnome-xml-parser.html">parser interfaces for XML</a> are
633separated from the <a href="html/gnome-xml-htmlparser.html">HTML parser
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]634interfaces</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]635
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]636<h3><a name="Invoking">Invoking the parser : the pull method</a></h3>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]637
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]638<p>Usually, the first thing to do is to read an XML input. The parser accepts
639documents either from in-memory strings or from files. The functions are
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]640defined in "parser.h":</p>
Daniel Veillard10c6a8f1998-10-28 01:00:12 +0000[diff] [blame]641<dl>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]642 <dt><code>xmlDocPtr xmlParseMemory(char *buffer, int size);</code></dt>
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]643 <dd><p>Parse a null-terminated string containing the document.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]644 </dd>
Daniel Veillard10c6a8f1998-10-28 01:00:12 +0000[diff] [blame]645</dl>
646<dl>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]647 <dt><code>xmlDocPtr xmlParseFile(const char *filename);</code></dt>
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]648 <dd><p>Parse an XML document contained in a (possibly compressed)
649 file.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]650 </dd>
Daniel Veillard10c6a8f1998-10-28 01:00:12 +0000[diff] [blame]651</dl>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]652
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]653<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]654failure).</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]655
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]656<h3 id="Invoking1">Invoking the parser: the push method</h3>
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]657
658<p>In order for the application to keep the control when the document is been
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]659fetched (which is common for GUI based programs) libxml provides a push
660interface, too, as of version 1.8.3. Here are the interface functions:</p>
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]661<pre>xmlParserCtxtPtr xmlCreatePushParserCtxt(xmlSAXHandlerPtr sax,
662 void *user_data,
663 const char *chunk,
664 int size,
665 const char *filename);
666int xmlParseChunk (xmlParserCtxtPtr ctxt,
667 const char *chunk,
668 int size,
669 int terminate);</pre>
670
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]671<p>and here is a simple example showing how to use the interface:</p>
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]672<pre> FILE *f;
673
674 f = fopen(filename, "r");
675 if (f != NULL) {
676 int res, size = 1024;
677 char chars[1024];
678 xmlParserCtxtPtr ctxt;
679
680 res = fread(chars, 1, 4, f);
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]681 if (res &gt; 0) {
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]682 ctxt = xmlCreatePushParserCtxt(NULL, NULL,
683 chars, res, filename);
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]684 while ((res = fread(chars, 1, size, f)) &gt; 0) {
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]685 xmlParseChunk(ctxt, chars, res, 0);
686 }
687 xmlParseChunk(ctxt, chars, 0, 1);
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]688 doc = ctxt-&gt;myDoc;
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]689 xmlFreeParserCtxt(ctxt);
690 }
691 }</pre>
692
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]693<p>Also note that the HTML parser embedded into libxml also has a push
694interface; the functions are just prefixed by "html" rather than "xml"</p>
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]695
696<h3 id="Invoking2">Invoking the parser: the SAX interface</h3>
697
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]698<p>A couple of comments can be made, first this mean that the parser is
Daniel Veillard10c6a8f1998-10-28 01:00:12 +0000[diff] [blame]699memory-hungry, first to load the document in memory, second to build the tree.
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]700Reading a document without building the tree is possible using the SAX
701interfaces (see SAX.h and <a
702href="http://www.daa.com.au/~james/gnome/xml-sax/xml-sax.html">James
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]703Henstridge's documentation</a>). Note also that the push interface can be
704limited to SAX. Just use the two first arguments of
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]705<code>xmlCreatePushParserCtxt()</code>.</p>
Daniel Veillardccb09631998-10-27 06:21:04 +0000[diff] [blame]706
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]707<h3><a name="Building">Building a tree from scratch</a></h3>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]708
709<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]710there is a set of functions dedicated to building new elements. (These are
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]711also described in &lt;libxml/tree.h&gt;.) For example, here is a piece of code
Daniel Veillard361d8452000-04-03 19:48:13 +0000[diff] [blame]712that produces the XML document used in the previous examples:</p>
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]713<pre> #include &lt;libxml/tree.h&gt;
Daniel Veillard361d8452000-04-03 19:48:13 +0000[diff] [blame]714 xmlDocPtr doc;
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]715 xmlNodePtr tree, subtree;
716
717 doc = xmlNewDoc("1.0");
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]718 doc-&gt;children = xmlNewDocNode(doc, NULL, "EXAMPLE", NULL);
719 xmlSetProp(doc-&gt;children, "prop1", "gnome is great");
720 xmlSetProp(doc-&gt;children, "prop2", "&amp; linux too");
721 tree = xmlNewChild(doc-&gt;children, NULL, "head", NULL);
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]722 subtree = xmlNewChild(tree, NULL, "title", "Welcome to Gnome");
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]723 tree = xmlNewChild(doc-&gt;children, NULL, "chapter", NULL);
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]724 subtree = xmlNewChild(tree, NULL, "title", "The Linux adventure");
725 subtree = xmlNewChild(tree, NULL, "p", "bla bla bla ...");
726 subtree = xmlNewChild(tree, NULL, "image", NULL);
727 xmlSetProp(subtree, "href", "linus.gif");</pre>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]728
729<p>Not really rocket science ...</p>
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]730
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]731<h3><a name="Traversing">Traversing the tree</a></h3>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]732
Daniel Veillard306be992000-07-03 12:38:45 +0000[diff] [blame]733<p>Basically by <a href="html/gnome-xml-tree.html">including "tree.h"</a> your
734code has access to the internal structure of all the elements of the tree. The
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]735names should be somewhat simple like <strong>parent</strong>,
Daniel Veillard306be992000-07-03 12:38:45 +0000[diff] [blame]736<strong>children</strong>, <strong>next</strong>, <strong>prev</strong>,
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]737<strong>properties</strong>, etc... For example, still with the previous
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]738example:</p>
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]739<pre><code>doc-&gt;children-&gt;children-&gt;children</code></pre>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]740
741<p>points to the title element,</p>
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]742<pre>doc-&gt;children-&gt;children-&gt;next-&gt;child-&gt;child</pre>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]743
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]744<p>points to the text node containing the chapter title "The Linux
745adventure".</p>
Daniel Veillard10c6a8f1998-10-28 01:00:12 +0000[diff] [blame]746
Daniel Veillardb24054a1999-12-18 15:32:46 +0000[diff] [blame]747<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]748present before the document root, so <code>doc-&gt;children</code> may point
749to an element which is not the document Root Element, a function
Daniel Veillard5cb5ab81999-12-21 15:35:29 +0000[diff] [blame]750<code>xmlDocGetRootElement()</code> was added for this purpose.</p>
Daniel Veillardb24054a1999-12-18 15:32:46 +0000[diff] [blame]751
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]752<h3><a name="Modifying">Modifying the tree</a></h3>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]753
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]754<p>Functions are provided for reading and writing the document content. Here
Daniel Veillardc19fccc2000-07-03 11:52:01 +0000[diff] [blame]755is an excerpt from the <a href="html/gnome-xml-tree.html">tree API</a>:</p>
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]756<dl>
Daniel Veillarddd6b3671999-09-23 22:19:22 +0000[diff] [blame]757 <dt><code>xmlAttrPtr xmlSetProp(xmlNodePtr node, const xmlChar *name, const
758 xmlChar *value);</code></dt>
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]759 <dd><p>This sets (or changes) an attribute carried by an ELEMENT node. The
760 value can be NULL.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]761 </dd>
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]762</dl>
763<dl>
Daniel Veillarddd6b3671999-09-23 22:19:22 +0000[diff] [blame]764 <dt><code>const xmlChar *xmlGetProp(xmlNodePtr node, const xmlChar
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]765 *name);</code></dt>
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]766 <dd><p>This function returns a pointer to the property content. Note that
767 no extra copy is made.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]768 </dd>
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]769</dl>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]770
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]771<p>Two functions are provided for reading and writing the text associated with
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]772elements:</p>
773<dl>
Daniel Veillarddd6b3671999-09-23 22:19:22 +0000[diff] [blame]774 <dt><code>xmlNodePtr xmlStringGetNodeList(xmlDocPtr doc, const xmlChar
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]775 *value);</code></dt>
776 <dd><p>This function takes an "external" string and convert it to one text
777 node or possibly to a list of entity and text nodes. All non-predefined
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]778 entity references like &amp;Gnome; will be stored internally as entity
779 nodes, hence the result of the function may not be a single node.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]780 </dd>
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]781</dl>
782<dl>
Daniel Veillarddd6b3671999-09-23 22:19:22 +0000[diff] [blame]783 <dt><code>xmlChar *xmlNodeListGetString(xmlDocPtr doc, xmlNodePtr list, int
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]784 inLine);</code></dt>
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]785 <dd><p>This function is the inverse of
786 <code>xmlStringGetNodeList()</code>. It generates a new string
787 containing the content of the text and entity nodes. Note the extra
788 argument inLine. If this argument is set to 1, the function will expand
789 entity references. For example, instead of returning the &amp;Gnome;
790 XML encoding in the string, it will substitute it with its value (say,
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]791 "GNU Network Object Model Environment"). Set this argument if you want
792 to use the string for non-XML usage like User Interface.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]793 </dd>
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]794</dl>
Daniel Veillard10c6a8f1998-10-28 01:00:12 +0000[diff] [blame]795
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]796<h3><a name="Saving">Saving a tree</a></h3>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]797
798<p>Basically 3 options are possible:</p>
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]799<dl>
Daniel Veillarddd6b3671999-09-23 22:19:22 +0000[diff] [blame]800 <dt><code>void xmlDocDumpMemory(xmlDocPtr cur, xmlChar**mem, int
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]801 *size);</code></dt>
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]802 <dd><p>Returns a buffer into which the document has been saved.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]803 </dd>
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]804</dl>
805<dl>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]806 <dt><code>extern void xmlDocDump(FILE *f, xmlDocPtr doc);</code></dt>
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]807 <dd><p>Dumps a document to an open file descriptor.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]808 </dd>
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]809</dl>
810<dl>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]811 <dt><code>int xmlSaveFile(const char *filename, xmlDocPtr cur);</code></dt>
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]812 <dd><p>Saves the document to a file. In this case, the compression
813 interface is triggered if it has been turned on.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]814 </dd>
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]815</dl>
Daniel Veillard10c6a8f1998-10-28 01:00:12 +0000[diff] [blame]816
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]817<h3><a name="Compressio">Compression</a></h3>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]818
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]819<p>The library transparently handles compression when doing file-based
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]820accesses. The level of compression on saves can be turned on either globally
821or individually for one file:</p>
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]822<dl>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]823 <dt><code>int xmlGetDocCompressMode (xmlDocPtr doc);</code></dt>
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]824 <dd><p>Gets the document compression ratio (0-9).</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]825 </dd>
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]826</dl>
827<dl>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]828 <dt><code>void xmlSetDocCompressMode (xmlDocPtr doc, int mode);</code></dt>
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]829 <dd><p>Sets the document compression ratio.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]830 </dd>
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]831</dl>
832<dl>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]833 <dt><code>int xmlGetCompressMode(void);</code></dt>
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]834 <dd><p>Gets the default compression ratio.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]835 </dd>
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]836</dl>
837<dl>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]838 <dt><code>void xmlSetCompressMode(int mode);</code></dt>
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]839 <dd><p>Sets the default compression ratio.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]840 </dd>
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]841</dl>
842
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]843<h2><a name="Entities">Entities or no entities</a></h2>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]844
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]845<p>Entities in principle are similar to simple C macros. An entity defines an
846abbreviation for a given string that you can reuse many times throughout the
847content of your document. Entities are especially useful when a given string
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]848may occur frequently within a document, or to confine the change needed to a
849document to a restricted area in the internal subset of the document (at the
850beginning). Example:</p>
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]851<pre>1 &lt;?xml version="1.0"?&gt;
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]8522 &lt;!DOCTYPE EXAMPLE SYSTEM "example.dtd" [
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]8533 &lt;!ENTITY xml "Extensible Markup Language"&gt;
8544 ]&gt;
8555 &lt;EXAMPLE&gt;
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]8566 &amp;xml;
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]8577 &lt;/EXAMPLE&gt;</pre>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]858
859<p>Line 3 declares the xml entity. Line 6 uses the xml entity, by prefixing
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]860it's name with '&amp;' and following it by ';' without any spaces added. There
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]861are 5 predefined entities in libxml allowing you to escape charaters with
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]862predefined meaning in some parts of the xml document content:
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]863<strong>&amp;lt;</strong> for the character '&lt;', <strong>&amp;gt;</strong>
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]864for the character '&gt;', <strong>&amp;apos;</strong> for the character ''',
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]865<strong>&amp;quot;</strong> for the character '"', and
866<strong>&amp;amp;</strong> for the character '&amp;'.</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]867
868<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]869substitute an entity's content so that you can see the replacement text in
870your application. Or you may prefer to keep entity references as such in the
871content to be able to save the document back without losing this usually
872precious information (if the user went through the pain of explicitly defining
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]873entities, he may have a a rather negative attitude if you blindly susbtitute
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]874them as saving time). The <a
Daniel Veillardc19fccc2000-07-03 11:52:01 +0000[diff] [blame]875href="html/gnome-xml-parser.html#XMLSUBSTITUTEENTITIESDEFAULT">xmlSubstituteEntitiesDefault()</a>
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]876function allows you to check and change the behaviour, which is to not
877substitute entities by default.</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]878
879<p>Here is the DOM tree built by libxml for the previous document in the
880default case:</p>
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]881<pre>/gnome/src/gnome-xml -&gt; ./xmllint --debug test/ent1
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]882DOCUMENT
883version=1.0
884 ELEMENT EXAMPLE
885 TEXT
886 content=
887 ENTITY_REF
888 INTERNAL_GENERAL_ENTITY xml
889 content=Extensible Markup Language
890 TEXT
891 content=</pre>
892
893<p>And here is the result when substituting entities:</p>
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]894<pre>/gnome/src/gnome-xml -&gt; ./tester --debug --noent test/ent1
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]895DOCUMENT
896version=1.0
897 ELEMENT EXAMPLE
898 TEXT
899 content= Extensible Markup Language</pre>
900
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]901<p>So, entities or no entities? Basically, it depends on your use case. I
902suggest that you keep the non-substituting default behaviour and avoid using
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]903entities in your XML document or data if you are not willing to handle the
904entity references elements in the DOM tree.</p>
905
906<p>Note that at save time libxml enforce the conversion of the predefined
907entities where necessary to prevent well-formedness problems, and will also
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]908transparently replace those with chars (i.e., it will not generate entity
909reference elements in the DOM tree or call the reference() SAX callback when
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]910finding them in the input).</p>
911
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]912<h2><a name="Namespaces">Namespaces</a></h2>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]913
Daniel Veillardec303412000-03-24 13:41:54 +0000[diff] [blame]914<p>The libxml library implements <a
915href="http://www.w3.org/TR/REC-xml-names/">XML namespaces</a> support by
916recognizing namespace contructs in the input, and does namespace lookup
917automatically when building the DOM tree. A namespace declaration is
918associated with an in-memory structure and all elements or attributes within
919that namespace point to it. Hence testing the namespace is a simple and fast
920equality operation at the user level.</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]921
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]922<p>I suggest that people using libxml use a namespace, and declare it in the
923root element of their document as the default namespace. Then they don't need
924to use the prefix in the content but we will have a basis for future semantic
925refinement and merging of data from different sources. This doesn't augment
926significantly the size of the XML output, but significantly increase its value
Daniel Veillardec303412000-03-24 13:41:54 +0000[diff] [blame]927in the long-term. Example:</p>
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]928<pre>&lt;mydoc xmlns="http://mydoc.example.org/schemas/"&gt;
929 &lt;elem1&gt;...&lt;/elem1&gt;
930 &lt;elem2&gt;...&lt;/elem2&gt;
931&lt;/mydoc&gt;</pre>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]932
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]933<p>Concerning the namespace value, this has to be an URL, but the URL doesn't
Daniel Veillardec303412000-03-24 13:41:54 +0000[diff] [blame]934have to point to any existing resource on the Web. It will bind all the
935element and atributes with that URL. I suggest to use an URL within a domain
936you control, and that the URL should contain some kind of version information
937if possible. For example, <code>"http://www.gnome.org/gnumeric/1.0/"</code> is
Daniel Veillard361d8452000-04-03 19:48:13 +0000[diff] [blame]938a good namespace scheme.</p>
Daniel Veillardec303412000-03-24 13:41:54 +0000[diff] [blame]939
940<p>Then when you load a file, make sure that a namespace carrying the
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]941version-independent prefix is installed on the root element of your document,
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]942and if the version information don't match something you know, warn the user
943and 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]944namespace checking on the prefix value. &lt;foo:text&gt; may be exactly the
945same as &lt;bar:text&gt; in another document. What really matter is the URI
946associated with the element or the attribute, not the prefix string (which is
947just a shortcut for the full URI). In libxml element and attributes have a
Daniel Veillardec303412000-03-24 13:41:54 +0000[diff] [blame]948<code>ns</code> field pointing to an xmlNs structure detailing the namespace
949prefix and it's URI.</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]950
951<p>@@Interfaces@@</p>
952
953<p>@@Examples@@</p>
954
955<p>Usually people object using namespace in the case of validation, I object
956this and will make sure that using namespaces won't break validity checking,
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]957so even is you plan to use or currently are using validation I strongly
958suggest adding namespaces to your document. A default namespace scheme
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]959<code>xmlns="http://...."</code> should not break validity even on less
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]960flexible parsers. Now using namespace to mix and differentiate content coming
961from multiple DTDs will certainly break current validation schemes. I will try
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]962to provide ways to do this, but this may not be portable or standardized.</p>
963
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]964<h2><a name="Validation">Validation, or are you afraid of DTDs ?</a></h2>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]965
966<p>Well what is validation and what is a DTD ?</p>
967
968<p>Validation is the process of checking a document against a set of
969construction rules, a <strong>DTD</strong> (Document Type Definition) is such
970a set of rules.</p>
971
972<p>The validation process and building DTDs are the two most difficult parts
973of XML life cycle. Briefly a DTD defines all the possibles element to be
974found within your document, what is the formal shape of your document tree (by
975defining the allowed content of an element, either text, a regular expression
Daniel Veillard306be992000-07-03 12:38:45 +0000[diff] [blame]976for the allowed list of children, or mixed content i.e. both text and
977children). The DTD also defines the allowed attributes for all elements and
978the types of the attributes. For more detailed informations, I suggest to read
979the related parts of the XML specification, the examples found under
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]980gnome-xml/test/valid/dtd and the large amount of books available on XML. The
981dia example in gnome-xml/test/valid should be both simple and complete enough
982to allow you to build your own.</p>
983
984<p>A word of warning, building a good DTD which will fit your needs of your
985application in the long-term is far from trivial, however the extra level of
986quality it can insure is well worth the price for some sets of applications or
987if you already have already a DTD defined for your application field.</p>
988
989<p>The validation is not completely finished but in a (very IMHO) usable
990state. Until a real validation interface is defined the way to do it is to
991define and set the <strong>xmlDoValidityCheckingDefaultValue</strong> external
992variable to 1, this will of course be changed at some point:</p>
993
994<p>extern int xmlDoValidityCheckingDefaultValue;</p>
995
996<p>...</p>
997
998<p>xmlDoValidityCheckingDefaultValue = 1;</p>
999
1000<p></p>
1001
1002<p>To handle external entities, use the function
1003<strong>xmlSetExternalEntityLoader</strong>(xmlExternalEntityLoader f); to
1004link in you HTTP/FTP/Entities database library to the standard libxml
1005core.</p>
1006
1007<p>@@interfaces@@</p>
1008
Daniel Veillard35008381999-10-25 13:15:52 +0000[diff] [blame]1009<h2><a name="DOM"></a><a name="Principles">DOM Principles</a></h2>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]1010
1011<p><a href="http://www.w3.org/DOM/">DOM</a> stands for the <em>Document Object
Daniel Veillardccb09631998-10-27 06:21:04 +0000[diff] [blame]1012Model</em> this is an API for accessing XML or HTML structured documents.
1013Native support for DOM in Gnome is on the way (module gnome-dom), and it will
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]1014be based on gnome-xml. This will be a far cleaner interface to manipulate XML
Daniel Veillardc08a2c61999-09-08 21:35:25 +0000[diff] [blame]1015files within Gnome since it won't expose the internal structure. DOM defines a
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]1016set of IDL (or Java) interfaces allowing to traverse and manipulate a
1017document. The DOM library will allow accessing and modifying "live" documents
1018presents on other programs like this:</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]1019
1020<p><img src="DOM.gif" alt=" DOM.gif "></p>
1021
1022<p>This should help greatly doing things like modifying a gnumeric spreadsheet
Daniel Veillardccb09631998-10-27 06:21:04 +0000[diff] [blame]1023embedded in a GWP document for example.</p>
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]1024
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]1025<p>The current DOM implementation on top of libxml is the <a
1026href="http://cvs.gnome.org/lxr/source/gdome/">gdome Gnome module</a>, this is
1027a full DOM interface, thanks to <a href="mailto:raph@levien.com">Raph
1028Levien</a>.</p>
1029
1030<p>The gnome-dom module in the Gnome CVS base is obsolete</p>
1031
Daniel Veillard35008381999-10-25 13:15:52 +0000[diff] [blame]1032<h2><a name="Example"></a><a name="real">A real example</a></h2>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]1033
1034<p>Here is a real size example, where the actual content of the application
1035data 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]1036a proposal to keep a database of jobs related to Gnome, with an XML based
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]1037storage structure. Here is an <a href="gjobs.xml">XML encoded jobs
1038base</a>:</p>
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]1039<pre>&lt;?xml version="1.0"?&gt;
1040&lt;gjob:Helping xmlns:gjob="http://www.gnome.org/some-location"&gt;
1041 &lt;gjob:Jobs&gt;
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]1042
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]1043 &lt;gjob:Job&gt;
1044 &lt;gjob:Project ID="3"/&gt;
1045 &lt;gjob:Application&gt;GBackup&lt;/gjob:Application&gt;
1046 &lt;gjob:Category&gt;Development&lt;/gjob:Category&gt;
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]1047
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]1048 &lt;gjob:Update&gt;
1049 &lt;gjob:Status&gt;Open&lt;/gjob:Status&gt;
1050 &lt;gjob:Modified&gt;Mon, 07 Jun 1999 20:27:45 -0400 MET DST&lt;/gjob:Modified&gt;
1051 &lt;gjob:Salary&gt;USD 0.00&lt;/gjob:Salary&gt;
1052 &lt;/gjob:Update&gt;
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]1053
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]1054 &lt;gjob:Developers&gt;
1055 &lt;gjob:Developer&gt;
1056 &lt;/gjob:Developer&gt;
1057 &lt;/gjob:Developers&gt;
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]1058
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]1059 &lt;gjob:Contact&gt;
1060 &lt;gjob:Person&gt;Nathan Clemons&lt;/gjob:Person&gt;
1061 &lt;gjob:Email&gt;nathan@windsofstorm.net&lt;/gjob:Email&gt;
1062 &lt;gjob:Company&gt;
1063 &lt;/gjob:Company&gt;
1064 &lt;gjob:Organisation&gt;
1065 &lt;/gjob:Organisation&gt;
1066 &lt;gjob:Webpage&gt;
1067 &lt;/gjob:Webpage&gt;
1068 &lt;gjob:Snailmail&gt;
1069 &lt;/gjob:Snailmail&gt;
1070 &lt;gjob:Phone&gt;
1071 &lt;/gjob:Phone&gt;
1072 &lt;/gjob:Contact&gt;
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]1073
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]1074 &lt;gjob:Requirements&gt;
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]1075 The program should be released as free software, under the GPL.
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]1076 &lt;/gjob:Requirements&gt;
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]1077
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]1078 &lt;gjob:Skills&gt;
1079 &lt;/gjob:Skills&gt;
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]1080
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]1081 &lt;gjob:Details&gt;
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]1082 A GNOME based system that will allow a superuser to configure
1083 compressed and uncompressed files and/or file systems to be backed
1084 up with a supported media in the system. This should be able to
1085 perform via find commands generating a list of files that are passed
1086 to tar, dd, cpio, cp, gzip, etc., to be directed to the tape machine
1087 or via operations performed on the filesystem itself. Email
1088 notification and GUI status display very important.
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]1089 &lt;/gjob:Details&gt;
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]1090
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]1091 &lt;/gjob:Job&gt;
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]1092
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]1093 &lt;/gjob:Jobs&gt;
1094&lt;/gjob:Helping&gt;</pre>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]1095
1096<p>While loading the XML file into an internal DOM tree is a matter of calling
1097only a couple of functions, browsing the tree to gather the informations and
1098generate the internals structures is harder, and more error prone.</p>
1099
1100<p>The suggested principle is to be tolerant with respect to the input
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]1101structure. For example, the ordering of the attributes is not significant,
1102Cthe XML specification is clear about it. It's also usually a good idea to not
Daniel Veillard306be992000-07-03 12:38:45 +0000[diff] [blame]1103be dependent of the orders of the children of a given node, unless it really
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]1104makes things harder. Here is some code to parse the informations for a
1105person:</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]1106<pre>/*
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]1107 * A person record
1108 */
1109typedef struct person {
1110 char *name;
1111 char *email;
1112 char *company;
1113 char *organisation;
1114 char *smail;
1115 char *webPage;
1116 char *phone;
1117} person, *personPtr;
1118
1119/*
1120 * And the code needed to parse it
1121 */
1122personPtr parsePerson(xmlDocPtr doc, xmlNsPtr ns, xmlNodePtr cur) {
1123 personPtr ret = NULL;
1124
1125DEBUG("parsePerson\n");
1126 /*
1127 * allocate the struct
1128 */
1129 ret = (personPtr) malloc(sizeof(person));
1130 if (ret == NULL) {
1131 fprintf(stderr,"out of memory\n");
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]1132 return(NULL);
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]1133 }
1134 memset(ret, 0, sizeof(person));
1135
1136 /* We don't care what the top level element name is */
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]1137 cur = cur-&gt;xmlChildrenNode;
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]1138 while (cur != NULL) {
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]1139 if ((!strcmp(cur-&gt;name, "Person")) &amp;&amp; (cur-&gt;ns == ns))
1140 ret-&gt;name = xmlNodeListGetString(doc, cur-&gt;xmlChildrenNode, 1);
1141 if ((!strcmp(cur-&gt;name, "Email")) &amp;&amp; (cur-&gt;ns == ns))
1142 ret-&gt;email = xmlNodeListGetString(doc, cur-&gt;xmlChildrenNode, 1);
1143 cur = cur-&gt;next;
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]1144 }
1145
1146 return(ret);
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]1147}</pre>
1148
1149<p>Here is a couple of things to notice:</p>
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]1150<ul>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]1151 <li>Usually a recursive parsing style is the more convenient one, XML data
1152 being by nature subject to repetitive constructs and usualy exibit highly
1153 stuctured patterns.</li>
1154 <li>The two arguments of type <em>xmlDocPtr</em> and <em>xmlNsPtr</em>, i.e.
1155 the pointer to the global XML document and the namespace reserved to the
1156 application. Document wide information are needed for example to decode
1157 entities and it's a good coding practice to define a namespace for your
1158 application set of data and test that the element and attributes you're
1159 analyzing actually pertains to your application space. This is done by a
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]1160 simple equality test (cur-&gt;ns == ns).</li>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]1161 <li>To retrieve text and attributes value, it is suggested to use the
1162 function <em>xmlNodeListGetString</em> to gather all the text and entity
1163 reference nodes generated by the DOM output and produce an single text
1164 string.</li>
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]1165</ul>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]1166
1167<p>Here is another piece of code used to parse another level of the
1168structure:</p>
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]1169<pre>#include &lt;libxml/tree.h&gt;
Daniel Veillard361d8452000-04-03 19:48:13 +0000[diff] [blame]1170/*
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]1171 * a Description for a Job
1172 */
1173typedef struct job {
1174 char *projectID;
1175 char *application;
1176 char *category;
1177 personPtr contact;
1178 int nbDevelopers;
1179 personPtr developers[100]; /* using dynamic alloc is left as an exercise */
1180} job, *jobPtr;
1181
1182/*
1183 * And the code needed to parse it
1184 */
1185jobPtr parseJob(xmlDocPtr doc, xmlNsPtr ns, xmlNodePtr cur) {
1186 jobPtr ret = NULL;
1187
1188DEBUG("parseJob\n");
1189 /*
1190 * allocate the struct
1191 */
1192 ret = (jobPtr) malloc(sizeof(job));
1193 if (ret == NULL) {
1194 fprintf(stderr,"out of memory\n");
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]1195 return(NULL);
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]1196 }
1197 memset(ret, 0, sizeof(job));
1198
1199 /* We don't care what the top level element name is */
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]1200 cur = cur-&gt;xmlChildrenNode;
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]1201 while (cur != NULL) {
1202
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]1203 if ((!strcmp(cur-&gt;name, "Project")) &amp;&amp; (cur-&gt;ns == ns)) {
1204 ret-&gt;projectID = xmlGetProp(cur, "ID");
1205 if (ret-&gt;projectID == NULL) {
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]1206 fprintf(stderr, "Project has no ID\n");
1207 }
1208 }
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]1209 if ((!strcmp(cur-&gt;name, "Application")) &amp;&amp; (cur-&gt;ns == ns))
1210 ret-&gt;application = xmlNodeListGetString(doc, cur-&gt;xmlChildrenNode, 1);
1211 if ((!strcmp(cur-&gt;name, "Category")) &amp;&amp; (cur-&gt;ns == ns))
1212 ret-&gt;category = xmlNodeListGetString(doc, cur-&gt;xmlChildrenNode, 1);
1213 if ((!strcmp(cur-&gt;name, "Contact")) &amp;&amp; (cur-&gt;ns == ns))
1214 ret-&gt;contact = parsePerson(doc, ns, cur);
1215 cur = cur-&gt;next;
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]1216 }
1217
1218 return(ret);
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]1219}</pre>
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]1220
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]1221<p>One can notice that once used to it, writing this kind of code is quite
1222simple, but boring. Ultimately, it could be possble to write stubbers taking
1223either C data structure definitions, a set of XML examples or an XML DTD and
1224produce the code needed to import and export the content between C data and
1225XML storage. This is left as an exercise to the reader :-)</p>
1226
Daniel Veillard6f0adb52000-07-03 11:41:26 +0000[diff] [blame]1227<p>Feel free to use <a href="example/gjobread.c">the code for the full C
1228parsing example</a> as a template, it is also available with Makefile in the
1229Gnome CVS base under gnome-xml/example</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]1230
Daniel Veillardc310d562000-06-23 18:32:15 +0000[diff] [blame]1231<h2><a name="Contributi">Contributions</a></h2>
1232<ul>
1233 <li><a href="mailto:ari@btigate.com">Ari Johnson</a> provides a C++ wrapper
1234 for libxml:
1235 <p>Website: <a
1236 href="http://lusis.org/~ari/xml++/">http://lusis.org/~ari/xml++/</a></p>
1237 <p>Download: <a
1238 href="http://lusis.org/~ari/xml++/libxml++.tar.gz">http://lusis.org/~ari/xml++/libxml++.tar.gz</a></p>
1239 </li>
1240 <li><a href="mailto:doolin@cs.utk.edu">David Doolin</a> provides a
1241 precompiled Windows version
1242 <p><a
1243 href="http://www.ce.berkeley.edu/~doolin/code/libxmlwin32/">http://www.ce.berkeley.edu/~doolin/code/libxmlwin32/</a></p>
1244 </li>
Daniel Veillard3f6f7f62000-06-30 17:58:25 +0000[diff] [blame]1245 <li><a href="mailto:fnatter@gmx.net">Felix Natter</a> provided <a
1246 href="libxml-doc.el">an emacs module</a> to lookup libxml functions
1247 documentation</li>
Daniel Veillardc310d562000-06-23 18:32:15 +0000[diff] [blame]1248 <li><a href="mailto:sherwin@nlm.nih.gov">Ziying Sherwin</a> provided <a
1249 href="http://xmlsoft.org/messages/0488.html">man pages</a> (not yet
1250 integrated in the distribution)</li>
1251</ul>
1252
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]1253<p></p>
1254
1255<p><a href="mailto:Daniel.Veillard@w3.org">Daniel Veillard</a></p>
1256
Daniel Veillardec78c0f2000-08-25 10:25:23 +0000[diff] [blame^]1257<p>$Id: xml.html,v 1.46 2000/08/19 16:40:28 veillard Exp $</p>
Daniel Veillardccb09631998-10-27 06:21:04 +0000[diff] [blame]1258</body>
1259</html>