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4<head>
Daniel Veillardec78c0f2000-08-25 10:25:23 +00005 <title>The XML C library for Gnome</title>
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Daniel Veillard60979bd2000-07-10 12:17:33 +000011<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"
Daniel Veillardb370a742001-06-09 16:58:47 +000013alt="W3C Logo"></a><a href="http://www.redhat.com"><img src="redhat.gif"
14alt="Red Hat Logo"></a></p>
Daniel Veillardec303412000-03-24 13:41:54 +000015
Daniel Veillardec78c0f2000-08-25 10:25:23 +000016<h1 align="center">The XML C library for Gnome</h1>
Daniel Veillardb05deb71999-08-10 19:04:08 +000017
Daniel Veillardc8eab3a1999-09-04 18:27:23 +000018<h2 style="text-align: center">libxml, a.k.a. gnome-xml</h2>
19
20<p></p>
Daniel Veillard2f4dfc41999-09-24 14:03:48 +000021<ul>
22 <li><a href="#Introducti">Introduction</a></li>
23 <li><a href="#Documentat">Documentation</a></li>
Daniel Veillardd5f97f82000-09-17 16:38:14 +000024 <li><a href="#Reporting">Reporting bugs and getting help</a></li>
25 <li><a href="#help">how to help</a></li>
Daniel Veillard10a2c651999-12-12 13:03:50 +000026 <li><a href="#Downloads">Downloads</a></li>
Daniel Veillard2f4dfc41999-09-24 14:03:48 +000027 <li><a href="#News">News</a></li>
28 <li><a href="#XML">XML</a></li>
Daniel Veillard82687162001-01-22 15:32:01 +000029 <li><a href="#XSLT">XSLT</a></li>
Daniel Veillard2f4dfc41999-09-24 14:03:48 +000030 <li><a href="#tree">The tree output</a></li>
31 <li><a href="#interface">The SAX interface</a></li>
32 <li><a href="#library">The XML library interfaces</a>
33 <ul>
Daniel Veillard0142b842000-01-14 14:45:24 +000034 <li><a href="#Invoking">Invoking the parser: the pull way</a></li>
35 <li><a href="#Invoking">Invoking the parser: the push way</a></li>
36 <li><a href="#Invoking2">Invoking the parser: the SAX interface</a></li>
Daniel Veillard2f4dfc41999-09-24 14:03:48 +000037 <li><a href="#Building">Building a tree from scratch</a></li>
38 <li><a href="#Traversing">Traversing the tree</a></li>
39 <li><a href="#Modifying">Modifying the tree</a></li>
40 <li><a href="#Saving">Saving the tree</a></li>
41 <li><a href="#Compressio">Compression</a></li>
42 </ul>
43 </li>
44 <li><a href="#Entities">Entities or no entities</a></li>
45 <li><a href="#Namespaces">Namespaces</a></li>
46 <li><a href="#Validation">Validation</a></li>
47 <li><a href="#Principles">DOM principles</a></li>
48 <li><a href="#real">A real example</a></li>
Daniel Veillard96984452000-08-31 13:50:12 +000049 <li><a href="#Contributi">Contributions</a></li>
50</ul>
51
52<p>Separate documents:</p>
53<ul>
54 <li><a href="upgrade.html">upgrade instructions for migrating to
55 libxml2</a></li>
56 <li><a href="encoding.html">libxml Internationalization support</a></li>
57 <li><a href="xmlio.html">libxml Input/Output interfaces</a></li>
Daniel Veillard189446d2000-10-13 10:23:06 +000058 <li><a href="xmlmem.html">libxml Memory interfaces</a></li>
Daniel Veillarde7ead2d2001-08-22 23:44:09 +000059 <li><a href="catalog.html">libxml Catalog support</a></li>
Daniel Veillard300f7d62000-11-24 13:04:04 +000060 <li><a href="xmldtd.html">a short introduction about DTDs and
61 libxml</a></li>
Daniel Veillard6e6a6cc2001-02-15 15:55:44 +000062 <li><a href="http://xmlsoft.org/XSLT/">the libxslt page</a></li>
Daniel Veillard7b06bcb2001-06-22 16:03:51 +000063 <li><a href="http://www.cs.unibo.it/~casarini/gdome2/">the gdome2 page: a
64 standard DOM interface for libxml2</a></li>
Daniel Veillard2f4dfc41999-09-24 14:03:48 +000065</ul>
66
67<h2><a name="Introducti">Introduction</a></h2>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +000068
Daniel Veillardf13e1ed2000-03-06 07:41:49 +000069<p>This document describes libxml, the <a
Daniel Veillardec78c0f2000-08-25 10:25:23 +000070href="http://www.w3.org/XML/">XML</a> C library developped for the <a
71href="http://www.gnome.org/">Gnome</a> project. <a
72href="http://www.w3.org/XML/">XML is a standard</a> for building tag-based
73structured documents/data.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +000074
Daniel Veillard0142b842000-01-14 14:45:24 +000075<p>Here are some key points about libxml:</p>
76<ul>
Daniel Veillard189446d2000-10-13 10:23:06 +000077 <li>Libxml exports Push and Pull type parser interfaces for both XML and
78 HTML.</li>
Daniel Veillard91e9d582001-02-26 07:31:12 +000079 <li>Libxml can do DTD validation at parse time, using a parsed document
80 instance, or with an arbitrary DTD.</li>
81 <li>Libxml now includes nearly complete <a
Daniel Veillard8c2ecaf2001-07-10 17:53:07 +000082 href="http://www.w3.org/TR/xpath">XPath</a>, <a
83 href="http://www.w3.org/TR/xptr">XPointer</a> and <a
84 href="http://www.w3.org/TR/xinclude">XInclude</a> implementations.</li>
Daniel Veillardec78c0f2000-08-25 10:25:23 +000085 <li>It is written in plain C, making as few assumptions as possible, and
Daniel Veillard189446d2000-10-13 10:23:06 +000086 sticking closely to ANSI C/POSIX for easy embedding. Works on
Daniel Veillardab8500d2000-10-15 21:06:19 +000087 Linux/Unix/Windows, ported to a number of other platforms.</li>
Daniel Veillardec70e912001-02-26 20:10:45 +000088 <li>Basic support for HTTP and FTP client allowing aplications to fetch
89 remote resources</li>
Daniel Veillard91e9d582001-02-26 07:31:12 +000090 <li>The design is modular, most of the extensions can be compiled out.</li>
Daniel Veillard0142b842000-01-14 14:45:24 +000091 <li>The internal document repesentation is as close as possible to the <a
92 href="http://www.w3.org/DOM/">DOM</a> interfaces.</li>
93 <li>Libxml also has a <a href="http://www.megginson.com/SAX/index.html">SAX
Daniel Veillard402e8c82000-02-29 22:57:47 +000094 like interface</a>; the interface is designed to be compatible with <a
95 href="http://www.jclark.com/xml/expat.html">Expat</a>.</li>
Daniel Veillardec303412000-03-24 13:41:54 +000096 <li>This library is released both under the <a
97 href="http://www.w3.org/Consortium/Legal/copyright-software-19980720.html">W3C
Daniel Veillard189446d2000-10-13 10:23:06 +000098 IPR</a> and the <a href="http://www.gnu.org/copyleft/lesser.html">GNU
99 LGPL</a>. Use either at your convenience, basically this should make
100 everybody happy, if not, drop me a mail.</li>
Daniel Veillard0142b842000-01-14 14:45:24 +0000101</ul>
Daniel Veillardccb09631998-10-27 06:21:04 +0000102
Daniel Veillarde0c1d722001-03-21 10:28:36 +0000103<p>Warning: unless you are forced to because your application links with a
104Gnome library requiring it, <strong><span
105style="background-color: #FF0000">Do Not Use libxml1</span></strong>, use
106libxml2</p>
107
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000108<h2><a name="Documentat">Documentation</a></h2>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000109
Daniel Veillard402e8c82000-02-29 22:57:47 +0000110<p>There are some on-line resources about using libxml:</p>
Daniel Veillard0142b842000-01-14 14:45:24 +0000111<ol>
Daniel Veillard365e13b2000-07-02 07:56:37 +0000112 <li>Check the <a href="FAQ.html">FAQ</a></li>
Daniel Veillardc19fccc2000-07-03 11:52:01 +0000113 <li>Check the <a href="http://xmlsoft.org/html/libxml-lib.html">extensive
Daniel Veillard8c6d6af2000-08-25 17:14:13 +0000114 documentation</a> automatically extracted from code comments (using <a
115 href="http://cvs.gnome.org/bonsai/rview.cgi?cvsroot=/cvs/gnome&amp;dir=gtk-doc">gtk
116 doc</a>).</li>
Daniel Veillard8d869642000-07-14 12:12:59 +0000117 <li>Look at the documentation about <a href="encoding.html">libxml
118 internationalization support</a></li>
Daniel Veillard0142b842000-01-14 14:45:24 +0000119 <li>This page provides a global overview and <a href="#real">some
Daniel Veillard402e8c82000-02-29 22:57:47 +0000120 examples</a> on how to use libxml.</li>
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000121 <li><a href="mailto:james@daa.com.au">James Henstridge</a>
122 wrote <a
Daniel Veillard402e8c82000-02-29 22:57:47 +0000123 href="http://www.daa.com.au/~james/gnome/xml-sax/xml-sax.html">some nice
124 documentation</a> explaining how to use the libxml SAX interface.</li>
Daniel Veillard0142b842000-01-14 14:45:24 +0000125 <li>George Lebl wrote <a
126 href="http://www-4.ibm.com/software/developer/library/gnome3/">an article
Daniel Veillard402e8c82000-02-29 22:57:47 +0000127 for IBM developerWorks</a> about using libxml.</li>
Daniel Veillardec303412000-03-24 13:41:54 +0000128 <li>Check <a href="http://cvs.gnome.org/lxr/source/gnome-xml/TODO">the TODO
129 file</a></li>
130 <li>Read the <a href="upgrade.html">1.x to 2.x upgrade path</a>. If you are
131 starting a new project using libxml you should really use the 2.x
132 version.</li>
Daniel Veillard0142b842000-01-14 14:45:24 +0000133 <li>And don't forget to look at the <a href="/messages/">mailing-list
Daniel Veillardc310d562000-06-23 18:32:15 +0000134 archive</a>.</li>
Daniel Veillard0142b842000-01-14 14:45:24 +0000135</ol>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000136
Daniel Veillardd5f97f82000-09-17 16:38:14 +0000137<h2><a name="Reporting">Reporting bugs and getting help</a></h2>
Daniel Veillard4c3a2031999-11-19 17:46:26 +0000138
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000139<p>Well, bugs or missing features are always possible, and I will make a
140point of fixing them in a timely fashion. The best way to report a bug is to
141use the <a href="http://bugzilla.gnome.org/buglist.cgi?product=libxml">Gnome
142bug tracking database</a> (make sure to use the "libxml" module name). I look
143at reports there regularly and it's good to have a reminder when a bug is
144still open. Check the <a
145href="http://bugzilla.gnome.org/bugwritinghelp.html">instructions on
146reporting bugs</a> and be sure to specify that the bug is for the package
147libxml.</p>
Daniel Veillard4c3a2031999-11-19 17:46:26 +0000148
Daniel Veillard0142b842000-01-14 14:45:24 +0000149<p>There is also a mailing-list <a
Daniel Veillard3197f162001-04-04 00:40:08 +0000150href="mailto:xml@gnome.org">xml@gnome.org</a> for libxml, with an <a
151href="http://mail.gnome.org/archives/xml/">on-line archive</a> (<a
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000152href="http://xmlsoft.org/messages">old</a>). To subscribe to this list,
153please visit the <a
154href="http://mail.gnome.org/mailman/listinfo/xml">associated Web</a> page and
155follow the instructions. <strong>Do not send code, I won't debug it</strong>
156(but patches are really appreciated!).</p>
Daniel Veillard234547b2001-07-05 09:46:10 +0000157
158<p>Check the following too before posting:</p>
159<ul>
160 <li>make sure you are <a href="ftp://xmlsoft.org/">using a recent
161 version</a>, and that the problem still shows up in those</li>
162 <li>check the <a href="http://mail.gnome.org/archives/xml/">list
163 archives</a> to see if the problem was reported already, in this case
Daniel Veillarde7ead2d2001-08-22 23:44:09 +0000164 there is probably a fix available, similary check the <a
165 href="http://bugzilla.gnome.org/buglist.cgi?product=libxml">registered
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000166 open bugs</a></li>
Daniel Veillard234547b2001-07-05 09:46:10 +0000167 <li>make sure you can reproduce the bug with xmllint or one of the test
168 programs found in source in the distribution</li>
169 <li>Please send the command showing the error as well as the input (as an
170 attachement)</li>
171</ul>
Daniel Veillard0142b842000-01-14 14:45:24 +0000172
Daniel Veillard402e8c82000-02-29 22:57:47 +0000173<p>Alternatively, you can just send the bug to the <a
Daniel Veillard33a67802001-03-07 09:44:02 +0000174href="mailto:xml@gnome.org">xml@gnome.org</a> list; if it's really libxml
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000175related I will approve it.. Please do not send me mail directly especially
176for portability problem, it makes things really harder to track and in some
177cases I'm not the best person to answer a given question, ask the list
178instead.</p>
Daniel Veillard4c3a2031999-11-19 17:46:26 +0000179
Daniel Veillard91e9d582001-02-26 07:31:12 +0000180<p>Of course, bugs reported with a suggested patch for fixing them will
Daniel Veillardec303412000-03-24 13:41:54 +0000181probably be processed faster.</p>
182
183<p>If you're looking for help, a quick look at <a
Daniel Veillardf7ed3362001-08-17 12:01:21 +0000184href="http://mail.gnome.org/archives/xml/">the list archive</a> may actually
Daniel Veillardec303412000-03-24 13:41:54 +0000185provide the answer, I usually send source samples when answering libxml usage
Daniel Veillard6f0adb52000-07-03 11:41:26 +0000186questions. The <a href="http://xmlsoft.org/html/book1.html">auto-generated
Daniel Veillardec303412000-03-24 13:41:54 +0000187documentantion</a> is not as polished as I would like (i need to learn more
188about Docbook), but it's a good starting point.</p>
189
Daniel Veillardd5f97f82000-09-17 16:38:14 +0000190<h2><a name="help">How to help</a></h2>
191
192<p>You can help the project in various ways, the best thing to do first is to
193subscribe to the mailing-list as explained before, check the <a
Daniel Veillardf7ed3362001-08-17 12:01:21 +0000194href="http://mail.gnome.org/archives/xml/">archives </a>and the <a
195href="http://bugzilla.gnome.org/buglist.cgi?product=libxml">Gnome bug
Daniel Veillardd5f97f82000-09-17 16:38:14 +0000196database:</a>:</p>
197<ol>
198 <li>provide patches when you find problems</li>
Daniel Veillard189446d2000-10-13 10:23:06 +0000199 <li>provide the diffs when you port libxml to a new platform. They may not
Daniel Veillardab8500d2000-10-15 21:06:19 +0000200 be integrated in all cases but help pinpointing portability problems
201 and</li>
Daniel Veillard91e9d582001-02-26 07:31:12 +0000202 <li>provide documentation fixes (either as patches to the code comments or
Daniel Veillardd5f97f82000-09-17 16:38:14 +0000203 as HTML diffs).</li>
204 <li>provide new documentations pieces (translations, examples, etc ...)</li>
205 <li>Check the TODO file and try to close one of the items</li>
206 <li>take one of the points raised in the archive or the bug database and
Daniel Veillarde7ead2d2001-08-22 23:44:09 +0000207 provide a fix. <a href="mailto:daniel@veillard.com">Get in touch with me
208 </a>before to avoid synchronization problems and check that the suggested
209 fix will fit in nicely :-)</li>
Daniel Veillardd5f97f82000-09-17 16:38:14 +0000210</ol>
211
Daniel Veillard10a2c651999-12-12 13:03:50 +0000212<h2><a name="Downloads">Downloads</a></h2>
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000213
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000214<p>The latest versions of libxml can be found on <a
Daniel Veillard20c8cf22001-06-26 22:47:36 +0000215href="ftp://xmlsoft.org/">xmlsoft.org</a> (<a
216href="ftp://speakeasy.rpmfind.net/pub/libxml/">Seattle</a>, <a
217href="ftp://fr.rpmfind.net/pub/libxml/">France</a>) or on the <a
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000218href="ftp://ftp.gnome.org/pub/GNOME/MIRRORS.html">Gnome FTP server</a> either
Daniel Veillard10a2c651999-12-12 13:03:50 +0000219as a <a href="ftp://ftp.gnome.org/pub/GNOME/stable/sources/libxml/">source
Daniel Veillard306be992000-07-03 12:38:45 +0000220archive</a> or <a
Daniel Veillarda41123c2001-04-22 19:31:20 +0000221href="ftp://ftp.gnome.org/pub/GNOME/stable/redhat/i386/libxml/">RPM
222packages</a>. (NOTE that you need both the <a
Daniel Veillardc19fccc2000-07-03 11:52:01 +0000223href="http://rpmfind.net/linux/RPM/libxml2.html">libxml(2)</a> and <a
224href="http://rpmfind.net/linux/RPM/libxml2-devel.html">libxml(2)-devel</a>
Daniel Veillard95189532001-07-26 18:30:26 +0000225packages installed to compile applications using libxml.) <a
226href="mailto:izlatkovic@daenet.de">Igor Zlatkovic</a> is now the maintainer
227of the Windows port, <a
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000228href="http://www.fh-frankfurt.de/~igor/projects/libxml/index.html">he
229provides binaries</a></p>
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000230
Daniel Veillard6c8b1172000-03-01 00:40:41 +0000231<p><a name="Snapshot">Snapshot:</a></p>
232<ul>
233 <li>Code from the W3C cvs base libxml <a
Daniel Veillard33a67802001-03-07 09:44:02 +0000234 href="ftp://xmlsoft.org/cvs-snapshot.tar.gz">cvs-snapshot.tar.gz</a></li>
Daniel Veillard6c8b1172000-03-01 00:40:41 +0000235 <li>Docs, content of the web site, the list archive included <a
Daniel Veillard33a67802001-03-07 09:44:02 +0000236 href="ftp://xmlsoft.org/libxml-docs.tar.gz">libxml-docs.tar.gz</a></li>
Daniel Veillard6c8b1172000-03-01 00:40:41 +0000237</ul>
238
239<p><a name="Contribs">Contribs:</a></p>
240
241<p>I do accept external contributions, especially if compiling on another
242platform, get in touch with me to upload the package. I will keep them in the
Daniel Veillard33a67802001-03-07 09:44:02 +0000243<a href="ftp://xmlsoft.org/contribs/">contrib directory</a></p>
Daniel Veillard6c8b1172000-03-01 00:40:41 +0000244
Daniel Veillard82687162001-01-22 15:32:01 +0000245<p>Libxml is also available from CVS:</p>
Daniel Veillard10a2c651999-12-12 13:03:50 +0000246<ul>
Daniel Veillard10a2c651999-12-12 13:03:50 +0000247 <li><p>The <a
248 href="http://cvs.gnome.org/bonsai/rview.cgi?cvsroot=/cvs/gnome&amp;dir=gnome-xml">Gnome
Daniel Veillard402e8c82000-02-29 22:57:47 +0000249 CVS base</a>. Check the <a
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000250 href="http://developer.gnome.org/tools/cvs.html">Gnome CVS Tools</a>
251 page; the CVS module is <b>gnome-xml</b>.</p>
Daniel Veillard10a2c651999-12-12 13:03:50 +0000252 </li>
Daniel Veillard82687162001-01-22 15:32:01 +0000253 <li>The <strong>libxslt</strong> module is also present there</li>
Daniel Veillard10a2c651999-12-12 13:03:50 +0000254</ul>
255
256<h2><a name="News">News</a></h2>
257
Daniel Veillard944b5ff1999-12-15 19:08:24 +0000258<h3>CVS only : check the <a
259href="http://cvs.gnome.org/lxr/source/gnome-xml/ChangeLog">Changelog</a> file
Daniel Veillard189446d2000-10-13 10:23:06 +0000260for a really accurate description</h3>
Daniel Veillardab8500d2000-10-15 21:06:19 +0000261
Daniel Veillard91e9d582001-02-26 07:31:12 +0000262<p>Items floating around but not actively worked on, get in touch with me if
Daniel Veillardab8500d2000-10-15 21:06:19 +0000263you want to test those</p>
264<ul>
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000265 <li>Implementing <a href="http://xmlsoft.org/XSLT">XSLT</a>, this is done
266 as a separate C library on top of libxml called libxslt</li>
Daniel Veillard28929b22000-11-13 18:22:49 +0000267 <li>Finishing up <a href="http://www.w3.org/TR/xptr">XPointer</a> and <a
268 href="http://www.w3.org/TR/xinclude">XInclude</a></li>
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000269 <li>(seeems working but delayed from release) parsing/import of Docbook
270 SGML docs</li>
271</ul>
272
Daniel Veillard04382ae2001-09-12 18:51:30 +0000273<h3>2.4.4: Sep 12 2001</h3>
274<ul>
275 <li>added --convert to xmlcatalog, bug fixes and cleanups of XML
276 Catalog</li>
277 <li>a few bug fixes and some portability changes</li>
278 <li>some documentation cleanups</li>
279</ul>
280
Daniel Veillard39936902001-08-24 00:49:01 +0000281<h3>2.4.3: Aug 23 2001</h3>
282<ul>
283 <li>XML Catalog support see the doc</li>
284 <li>New NaN/Infinity floating point code</li>
285 <li>A few bug fixes</li>
286</ul>
287
288<h3>2.4.2: Aug 15 2001</h3>
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000289<ul>
290 <li>adds xmlLineNumbersDefault() to control line number generation</li>
291 <li>lot of bug fixes</li>
292 <li>the Microsoft MSC projects files shuld now be up to date</li>
293 <li>inheritance of namespaces from DTD defaulted attributes</li>
294 <li>fixes a serious potential security bug</li>
295 <li>added a --format option to xmllint</li>
296</ul>
297
298<h3>2.4.1: July 24 2001</h3>
299<ul>
300 <li>possibility to keep line numbers in the tree</li>
301 <li>some computation NaN fixes</li>
302 <li>extension of the XPath API</li>
303 <li>cleanup for alpha and ia64 targets</li>
304 <li>patch to allow saving through HTTP PUT or POST</li>
Daniel Veillard09ab7e12001-07-10 15:49:44 +0000305</ul>
306
307<h3>2.4.0: July 10 2001</h3>
308<ul>
309 <li>Fixed a few bugs in XPath, validation, and tree handling.</li>
310 <li>Fixed XML Base implementation, added a coupel of examples to the
311 regression tests</li>
312 <li>A bit of cleanup</li>
Daniel Veillardab8500d2000-10-15 21:06:19 +0000313</ul>
314
Daniel Veillard5b43fde2001-07-05 23:31:40 +0000315<h3>2.3.14: July 5 2001</h3>
316<ul>
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000317 <li>fixed some entities problems and reduce mem requirement when
318 substituing them</li>
Daniel Veillard5b43fde2001-07-05 23:31:40 +0000319 <li>lots of improvements in the XPath queries interpreter can be
320 substancially faster</li>
321 <li>Makefiles and configure cleanups</li>
322 <li>Fixes to XPath variable eval, and compare on empty node set</li>
323 <li>HTML tag closing bug fixed</li>
324 <li>Fixed an URI reference computating problem when validating</li>
325</ul>
326
Daniel Veillard2adbb512001-06-28 16:20:36 +0000327<h3>2.3.13: June 28 2001</h3>
328<ul>
329 <li>2.3.12 configure.in was broken as well as the push mode XML parser</li>
330 <li>a few more fixes for compilation on Windows MSC by Yon Derek</li>
331</ul>
332
333<h3>1.8.14: June 28 2001</h3>
334<ul>
335 <li>Zbigniew Chyla gave a patch to use the old XML parser in push mode</li>
336 <li>Small Makefile fix</li>
337</ul>
338
Daniel Veillard11648102001-06-26 16:08:24 +0000339<h3>2.3.12: June 26 2001</h3>
340<ul>
341 <li>lots of cleanup</li>
342 <li>a couple of validation fix</li>
343 <li>fixed line number counting</li>
344 <li>fixed serious problems in the XInclude processing</li>
345 <li>added support for UTF8 BOM at beginning of entities</li>
346 <li>fixed a strange gcc optimizer bugs in xpath handling of float, gcc-3.0
347 miscompile uri.c (William), Thomas Leitner provided a fix for the
348 optimizer on Tru64</li>
349 <li>incorporated Yon Derek and Igor Zlatkovic fixes and improvements for
350 compilation on Windows MSC</li>
351 <li>update of libxml-doc.el (Felix Natter)</li>
352 <li>fixed 2 bugs in URI normalization code</li>
353</ul>
354
Daniel Veillarde3c81b52001-06-17 14:50:34 +0000355<h3>2.3.11: June 17 2001</h3>
356<ul>
357 <li>updates to trio, Makefiles and configure should fix some portability
358 problems (alpha)</li>
359 <li>fixed some HTML serialization problems (pre, script, and block/inline
360 handling), added encoding aware APIs, cleanup of this code</li>
361 <li>added xmlHasNsProp()</li>
362 <li>implemented a specific PI for encoding support in the DocBook SGML
363 parser</li>
364 <li>some XPath fixes (-Infinity, / as a function parameter and namespaces
365 node selection)</li>
366 <li>fixed a performance problem and an error in the validation code</li>
367 <li>fixed XInclude routine to implement the recursive behaviour</li>
368 <li>fixed xmlFreeNode problem when libxml is included statically twice</li>
369 <li>added --version to xmllint for bug reports</li>
370</ul>
371
Daniel Veillard2e4f1882001-06-01 10:11:57 +0000372<h3>2.3.10: June 1 2001</h3>
373<ul>
374 <li>fixed the SGML catalog support</li>
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000375 <li>a number of reported bugs got fixed, in XPath, iconv detection,
376 XInclude processing</li>
Daniel Veillard2e4f1882001-06-01 10:11:57 +0000377 <li>XPath string function should now handle unicode correctly</li>
378</ul>
379
Daniel Veillard4623acd2001-05-19 15:13:15 +0000380<h3>2.3.9: May 19 2001</h3>
381
382<p>Lots of bugfixes, and added a basic SGML catalog support:</p>
383<ul>
384 <li>HTML push bugfix #54891 and another patch from Jonas Borgström</li>
385 <li>some serious speed optimisation again</li>
386 <li>some documentation cleanups</li>
387 <li>trying to get better linking on solaris (-R)</li>
388 <li>XPath API cleanup from Thomas Broyer</li>
389 <li>Validation bug fixed #54631, added a patch from Gary Pennington, fixed
390 xmlValidGetValidElements()</li>
391 <li>Added an INSTALL file</li>
392 <li>Attribute removal added to API: #54433</li>
393 <li>added a basic support for SGML catalogs</li>
394 <li>fixed xmlKeepBlanksDefault(0) API</li>
395 <li>bugfix in xmlNodeGetLang()</li>
396 <li>fixed a small configure portability problem</li>
397 <li>fixed an inversion of SYSTEM and PUBLIC identifier in HTML document</li>
398</ul>
399
Daniel Veillarda265af72001-05-14 11:13:58 +0000400<h3>1.8.13: May 14 2001</h3>
401<ul>
402 <li>bugfixes release of the old libxml1 branch used by Gnome</li>
403</ul>
404
Daniel Veillard3bbbe6f2001-05-03 11:15:37 +0000405<h3>2.3.8: May 3 2001</h3>
406<ul>
407 <li>Integrated an SGML DocBook parser for the Gnome project</li>
408 <li>Fixed a few things in the HTML parser</li>
409 <li>Fixed some XPath bugs raised by XSLT use, tried to fix the floating
410 point portability issue</li>
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000411 <li>Speed improvement (8M/s for SAX, 3M/s for DOM, 1.5M/s for
412 DOM+validation using the XML REC as input and a 700MHz celeron).</li>
Daniel Veillard3bbbe6f2001-05-03 11:15:37 +0000413 <li>incorporated more Windows cleanup</li>
414 <li>added xmlSaveFormatFile()</li>
415 <li>fixed problems in copying nodes with entities references (gdome)</li>
416 <li>removed some troubles surrounding the new validation module</li>
417</ul>
418
Daniel Veillarda41123c2001-04-22 19:31:20 +0000419<h3>2.3.7: April 22 2001</h3>
420<ul>
421 <li>lots of small bug fixes, corrected XPointer</li>
422 <li>Non determinist content model validation support</li>
423 <li>added xmlDocCopyNode for gdome2</li>
424 <li>revamped the way the HTML parser handles end of tags</li>
425 <li>XPath: corrctions of namespacessupport and number formatting</li>
426 <li>Windows: Igor Zlatkovic patches for MSC compilation</li>
427 <li>HTML ouput fixes from P C Chow and William M. Brack</li>
428 <li>Improved validation speed sensible for DocBook</li>
429 <li>fixed a big bug with ID declared in external parsed entities</li>
430 <li>portability fixes, update of Trio from Bjorn Reese</li>
431</ul>
432
Daniel Veillardafc73112001-04-11 11:51:41 +0000433<h3>2.3.6: April 8 2001</h3>
434<ul>
435 <li>Code cleanup using extreme gcc compiler warning options, found and
436 cleared half a dozen potential problem</li>
437 <li>the Eazel team found an XML parser bug</li>
438 <li>cleaned up the user of some of the string formatting function. used the
439 trio library code to provide the one needed when the platform is missing
440 them</li>
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000441 <li>xpath: removed a memory leak and fixed the predicate evaluation
442 problem, extended the testsuite and cleaned up the result. XPointer seems
443 broken ...</li>
Daniel Veillardafc73112001-04-11 11:51:41 +0000444</ul>
445
Daniel Veillard56a4cb82001-03-24 17:00:36 +0000446<h3>2.3.5: Mar 23 2001</h3>
447<ul>
448 <li>Biggest change is separate parsing and evaluation of XPath expressions,
449 there is some new APIs for this too</li>
450 <li>included a number of bug fixes(XML push parser, 51876, notations,
451 52299)</li>
452 <li>Fixed some portability issues</li>
453</ul>
454
Daniel Veillarde356c282001-03-10 12:32:04 +0000455<h3>2.3.4: Mar 10 2001</h3>
456<ul>
457 <li>Fixed bugs #51860 and #51861</li>
458 <li>Added a global variable xmlDefaultBufferSize to allow default buffer
459 size to be application tunable.</li>
460 <li>Some cleanup in the validation code, still a bug left and this part
461 should probably be rewritten to support ambiguous content model :-\</li>
462 <li>Fix a couple of serious bugs introduced or raised by changes in 2.3.3
463 parser</li>
464 <li>Fixed another bug in xmlNodeGetContent()</li>
465 <li>Bjorn fixed XPath node collection and Number formatting</li>
466 <li>Fixed a loop reported in the HTML parsing</li>
467 <li>blank space are reported even if the Dtd content model proves that they
468 are formatting spaces, this is for XmL conformance</li>
469</ul>
470
Daniel Veillardb402c072001-03-01 17:28:58 +0000471<h3>2.3.3: Mar 1 2001</h3>
472<ul>
473 <li>small change in XPath for XSLT</li>
474 <li>documentation cleanups</li>
475 <li>fix in validation by Gary Pennington</li>
476 <li>serious parsing performances improvements</li>
477</ul>
478
Daniel Veillardec70e912001-02-26 20:10:45 +0000479<h3>2.3.2: Feb 24 2001</h3>
Daniel Veillard71681102001-02-24 17:48:53 +0000480<ul>
481 <li>chasing XPath bugs, found a bunch, completed some TODO</li>
482 <li>fixed a Dtd parsing bug</li>
483 <li>fixed a bug in xmlNodeGetContent</li>
484 <li>ID/IDREF support partly rewritten by Gary Pennington</li>
485</ul>
486
Daniel Veillardec70e912001-02-26 20:10:45 +0000487<h3>2.3.1: Feb 15 2001</h3>
Daniel Veillard6e6a6cc2001-02-15 15:55:44 +0000488<ul>
489 <li>some XPath and HTML bug fixes for XSLT</li>
490 <li>small extension of the hash table interfaces for DOM gdome2
491 implementation</li>
492 <li>A few bug fixes</li>
493</ul>
494
Daniel Veillardec70e912001-02-26 20:10:45 +0000495<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 +0000496<ul>
497 <li>Lots of XPath bug fixes</li>
498 <li>Add a mode with Dtd lookup but without validation error reporting for
499 XSLT</li>
500 <li>Add support for text node without escaping (XSLT)</li>
501 <li>bug fixes for xmlCheckFilename</li>
502 <li>validation code bug fixes from Gary Pennington</li>
503 <li>Patch from Paul D. Smith correcting URI path normalization</li>
504 <li>Patch to allow simultaneous install of libxml-devel and
505 libxml2-devel</li>
506 <li>the example Makefile is now fixed</li>
507 <li>added HTML to the RPM packages</li>
508 <li>tree copying bugfixes</li>
509 <li>updates to Windows makefiles</li>
510 <li>optimisation patch from Bjorn Reese</li>
511</ul>
512
Daniel Veillardec70e912001-02-26 20:10:45 +0000513<h3>2.2.11: Jan 4 2001</h3>
Daniel Veillard503b8932001-01-05 06:36:31 +0000514<ul>
515 <li>bunch of bug fixes (memory I/O, xpath, ftp/http, ...)</li>
516 <li>added htmlHandleOmittedElem()</li>
517 <li>Applied Bjorn Reese's IPV6 first patch</li>
518 <li>Applied Paul D. Smith patches for validation of XInclude results</li>
Daniel Veillard82687162001-01-22 15:32:01 +0000519 <li>added XPointer xmlns() new scheme support</li>
Daniel Veillard503b8932001-01-05 06:36:31 +0000520</ul>
521
Daniel Veillard2ddd23d2000-11-25 10:42:19 +0000522<h3>2.2.10: Nov 25 2000</h3>
Daniel Veillard9d343c42000-11-25 10:12:43 +0000523<ul>
524 <li>Fix the Windows problems of 2.2.8</li>
525 <li>integrate OpenVMS patches</li>
526 <li>better handling of some nasty HTML input</li>
527 <li>Improved the XPointer implementation</li>
528 <li>integrate a number of provided patches</li>
529</ul>
530
Daniel Veillard2ddd23d2000-11-25 10:42:19 +0000531<h3>2.2.9: Nov 25 2000</h3>
532<ul>
533 <li>erroneous release :-(</li>
534</ul>
535
Daniel Veillard28929b22000-11-13 18:22:49 +0000536<h3>2.2.8: Nov 13 2000</h3>
537<ul>
538 <li>First version of <a href="http://www.w3.org/TR/xinclude">XInclude</a>
539 support</li>
540 <li>Patch in conditional section handling</li>
541 <li>updated MS compiler project</li>
542 <li>fixed some XPath problems</li>
543 <li>added an URI escaping function</li>
544 <li>some other bug fixes</li>
545</ul>
546
547<h3>2.2.7: Oct 31 2000</h3>
548<ul>
549 <li>added message redirection</li>
550 <li>XPath improvements (thanks TOM !)</li>
551 <li>xmlIOParseDTD() added</li>
552 <li>various small fixes in the HTML, URI, HTTP and XPointer support</li>
553 <li>some cleanup of the Makefile, autoconf and the distribution content</li>
554</ul>
555
Daniel Veillard29a11cc2000-10-25 13:32:39 +0000556<h3>2.2.6: Oct 25 2000:</h3>
557<ul>
558 <li>Added an hash table module, migrated a number of internal structure to
559 those</li>
560 <li>Fixed a posteriori validation problems</li>
561 <li>HTTP module cleanups</li>
562 <li>HTML parser improvements (tag errors, script/style handling, attribute
563 normalization)</li>
564 <li>coalescing of adjacent text nodes</li>
565 <li>couple of XPath bug fixes, exported the internal API</li>
566</ul>
567
Daniel Veillardab8500d2000-10-15 21:06:19 +0000568<h3>2.2.5: Oct 15 2000:</h3>
Daniel Veillard4c3a2031999-11-19 17:46:26 +0000569<ul>
Daniel Veillard189446d2000-10-13 10:23:06 +0000570 <li>XPointer implementation and testsuite</li>
571 <li>Lot of XPath fixes, added variable and functions registration, more
572 tests</li>
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000573 <li>Portability fixes, lots of enhancements toward an easy Windows build
574 and release</li>
Daniel Veillard189446d2000-10-13 10:23:06 +0000575 <li>Late validation fixes</li>
576 <li>Integrated a lot of contributed patches</li>
577 <li>added memory management docs</li>
Daniel Veillardab8500d2000-10-15 21:06:19 +0000578 <li>a performance problem when using large buffer seems fixed</li>
Daniel Veillard189446d2000-10-13 10:23:06 +0000579</ul>
580
581<h3>2.2.4: Oct 1 2000:</h3>
582<ul>
583 <li>main XPath problem fixed</li>
584 <li>Integrated portability patches for Windows</li>
585 <li>Serious bug fixes on the URI and HTML code</li>
Daniel Veillard361d8452000-04-03 19:48:13 +0000586</ul>
587
Daniel Veillardd5f97f82000-09-17 16:38:14 +0000588<h3>2.2.3: Sep 17 2000</h3>
589<ul>
590 <li>bug fixes</li>
591 <li>cleanup of entity handling code</li>
592 <li>overall review of all loops in the parsers, all sprintf usage has been
593 checked too</li>
594 <li>Far better handling of larges Dtd. Validating against Docbook XML Dtd
595 works smoothly now.</li>
596</ul>
597
598<h3>1.8.10: Sep 6 2000</h3>
599<ul>
600 <li>bug fix release for some Gnome projects</li>
601</ul>
602
603<h3>2.2.2: August 12 2000</h3>
Daniel Veillard786d7c82000-08-12 23:38:57 +0000604<ul>
605 <li>mostly bug fixes</li>
Daniel Veillardec78c0f2000-08-25 10:25:23 +0000606 <li>started adding routines to access xml parser context options</li>
Daniel Veillard786d7c82000-08-12 23:38:57 +0000607</ul>
608
Daniel Veillardd5f97f82000-09-17 16:38:14 +0000609<h3>2.2.1: July 21 2000</h3>
Daniel Veillarda2679fa2000-07-22 02:38:15 +0000610<ul>
611 <li>a purely bug fixes release</li>
612 <li>fixed an encoding support problem when parsing from a memory block</li>
613 <li>fixed a DOCTYPE parsing problem</li>
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000614 <li>removed a bug in the function allowing to override the memory
615 allocation routines</li>
Daniel Veillarda2679fa2000-07-22 02:38:15 +0000616</ul>
617
Daniel Veillardd5f97f82000-09-17 16:38:14 +0000618<h3>2.2.0: July 14 2000</h3>
Daniel Veillard94e90602000-07-17 14:38:19 +0000619<ul>
620 <li>applied a lot of portability fixes</li>
621 <li>better encoding support/cleanup and saving (content is now always
622 encoded in UTF-8)</li>
623 <li>the HTML parser now correctly handles encodings</li>
624 <li>added xmlHasProp()</li>
625 <li>fixed a serious problem with &amp;#38;</li>
626 <li>propagated the fix to FTP client</li>
627 <li>cleanup, bugfixes, etc ...</li>
628 <li>Added a page about <a href="encoding.html">libxml Internationalization
629 support</a></li>
630</ul>
631
Daniel Veillard60979bd2000-07-10 12:17:33 +0000632<h3>1.8.9: July 9 2000</h3>
633<ul>
634 <li>fixed the spec the RPMs should be better</li>
635 <li>fixed a serious bug in the FTP implementation, released 1.8.9 to solve
636 rpmfind users problem</li>
637</ul>
638
Daniel Veillard6388e172000-07-03 16:07:19 +0000639<h3>2.1.1: July 1 2000</h3>
640<ul>
641 <li>fixes a couple of bugs in the 2.1.0 packaging</li>
642 <li>improvements on the HTML parser</li>
643</ul>
644
Daniel Veillard3f6f7f62000-06-30 17:58:25 +0000645<h3>2.1.0 and 1.8.8: June 29 2000</h3>
646<ul>
647 <li>1.8.8 is mostly a comodity package for upgrading to libxml2 accoding to
648 <a href="upgrade.html">new instructions</a>. It fixes a nasty problem
649 about &amp;#38; charref parsing</li>
650 <li>2.1.0 also ease the upgrade from libxml v1 to the recent version. it
651 also contains numerous fixes and enhancements:
652 <ul>
653 <li>added xmlStopParser() to stop parsing</li>
654 <li>improved a lot parsing speed when there is large CDATA blocs</li>
655 <li>includes XPath patches provided by Picdar Technology</li>
656 <li>tried to fix as much as possible DtD validation and namespace
657 related problems</li>
658 <li>output to a given encoding has been added/tested</li>
659 <li>lot of various fixes</li>
660 </ul>
661 </li>
662</ul>
663
Daniel Veillarde0aed302000-04-16 08:52:20 +0000664<h3>2.0.0: Apr 12 2000</h3>
Daniel Veillard361d8452000-04-03 19:48:13 +0000665<ul>
666 <li>First public release of libxml2. If you are using libxml, it's a good
Daniel Veillarde0aed302000-04-16 08:52:20 +0000667 idea to check the 1.x to 2.x upgrade instructions. NOTE: while initally
668 scheduled for Apr 3 the relase occured only on Apr 12 due to massive
669 workload.</li>
Daniel Veillard361d8452000-04-03 19:48:13 +0000670 <li>The include are now located under $prefix/include/libxml (instead of
Daniel Veillarde0aed302000-04-16 08:52:20 +0000671 $prefix/include/gnome-xml), they also are referenced by
Daniel Veillard60979bd2000-07-10 12:17:33 +0000672 <pre>#include &lt;libxml/xxx.h&gt;</pre>
Daniel Veillarde0aed302000-04-16 08:52:20 +0000673 <p>instead of</p>
Daniel Veillard361d8452000-04-03 19:48:13 +0000674 <pre>#include "xxx.h"</pre>
675 </li>
Daniel Veillard8f621982000-03-20 13:07:15 +0000676 <li>a new URI module for parsing URIs and following strictly RFC 2396</li>
677 <li>the memory allocation routines used by libxml can now be overloaded
678 dynamically by using xmlMemSetup()</li>
Daniel Veillard361d8452000-04-03 19:48:13 +0000679 <li>The previously CVS only tool tester has been renamed
680 <strong>xmllint</strong> and is now installed as part of the libxml2
681 package</li>
Daniel Veillarde0aed302000-04-16 08:52:20 +0000682 <li>The I/O interface has been revamped. There is now ways to plug in
683 specific I/O modules, either at the URI scheme detection level using
684 xmlRegisterInputCallbacks() or by passing I/O functions when creating a
685 parser context using xmlCreateIOParserCtxt()</li>
686 <li>there is a C preprocessor macro LIBXML_VERSION providing the version
687 number of the libxml module in use</li>
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000688 <li>a number of optional features of libxml can now be excluded at
689 configure time (FTP/HTTP/HTML/XPath/Debug)</li>
Daniel Veillardedfb29b2000-03-14 19:59:05 +0000690</ul>
691
692<h3>2.0.0beta: Mar 14 2000</h3>
693<ul>
694 <li>This is a first Beta release of libxml version 2</li>
Daniel Veillarde356c282001-03-10 12:32:04 +0000695 <li>It's available only from<a href="ftp://xmlsoft.org/">xmlsoft.org
696 FTP</a>, it's packaged as libxml2-2.0.0beta and available as tar and
697 RPMs</li>
Daniel Veillardedfb29b2000-03-14 19:59:05 +0000698 <li>This version is now the head in the Gnome CVS base, the old one is
699 available under the tag LIB_XML_1_X</li>
700 <li>This includes a very large set of changes. Froma programmatic point of
701 view applications should not have to be modified too much, check the <a
702 href="upgrade.html">upgrade page</a></li>
703 <li>Some interfaces may changes (especially a bit about encoding).</li>
704 <li>the updates includes:
Daniel Veillard6c8b1172000-03-01 00:40:41 +0000705 <ul>
Daniel Veillardedfb29b2000-03-14 19:59:05 +0000706 <li>fix I18N support. ISO-Latin-x/UTF-8/UTF-16 (nearly) seems correctly
707 handled now</li>
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000708 <li>Better handling of entities, especially well formedness checking
709 and proper PEref extensions in external subsets</li>
Daniel Veillard6c8b1172000-03-01 00:40:41 +0000710 <li>DTD conditional sections</li>
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000711 <li>Validation now correcly handle entities content</li>
Daniel Veillard6c8b1172000-03-01 00:40:41 +0000712 <li><a href="http://rpmfind.net/tools/gdome/messages/0039.html">change
713 structures to accomodate DOM</a></li>
Daniel Veillard6c8b1172000-03-01 00:40:41 +0000714 </ul>
715 </li>
Daniel Veillardedfb29b2000-03-14 19:59:05 +0000716 <li>Serious progress were made toward compliance, <a
717 href="conf/result.html">here are the result of the test</a> against the
718 OASIS testsuite (except the japanese tests since I don't support that
719 encoding yet). This URL is rebuilt every couple of hours using the CVS
720 head version.</li>
Daniel Veillarde41f2b72000-01-30 20:00:07 +0000721</ul>
722
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000723<h3>1.8.7: Mar 6 2000</h3>
724<ul>
725 <li>This is a bug fix release:</li>
726 <li>It is possible to disable the ignorable blanks heuristic used by
727 libxml-1.x, a new function xmlKeepBlanksDefault(0) will allow this. Note
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000728 that for adherence to XML spec, this behaviour will be disabled by
729 default in 2.x . The same function will allow to keep compatibility for
730 old code.</li>
Daniel Veillard60979bd2000-07-10 12:17:33 +0000731 <li>Blanks in &lt;a&gt; &lt;/a&gt; constructs are not ignored anymore,
732 avoiding heuristic is really the Right Way :-\</li>
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000733 <li>The unchecked use of snprintf which was breaking libxml-1.8.6
734 compilation on some platforms has been fixed</li>
735 <li>nanoftp.c nanohttp.c: Fixed '#' and '?' stripping when processing
736 URIs</li>
737</ul>
738
Daniel Veillarde41f2b72000-01-30 20:00:07 +0000739<h3>1.8.6: Jan 31 2000</h3>
740<ul>
741 <li>added a nanoFTP transport module, debugged until the new version of <a
742 href="http://rpmfind.net/linux/rpm2html/rpmfind.html">rpmfind</a> can use
743 it without troubles</li>
Daniel Veillardda07c342000-01-25 18:31:22 +0000744</ul>
745
746<h3>1.8.5: Jan 21 2000</h3>
747<ul>
Daniel Veillard0142b842000-01-14 14:45:24 +0000748 <li>adding APIs to parse a well balanced chunk of XML (production <a
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000749 href="http://www.w3.org/TR/REC-xml#NT-content">[43] content</a> of the
750 XML spec)</li>
Daniel Veillard461a66c2000-01-18 18:01:01 +0000751 <li>fixed a hideous bug in xmlGetProp pointed by Rune.Djurhuus@fast.no</li>
Daniel Veillard60979bd2000-07-10 12:17:33 +0000752 <li>Jody Goldberg &lt;jgoldberg@home.com&gt; provided another patch trying
753 to solve the zlib checks problems</li>
Daniel Veillard461a66c2000-01-18 18:01:01 +0000754 <li>The current state in gnome CVS base is expected to ship as 1.8.5 with
755 gnumeric soon</li>
Daniel Veillard0142b842000-01-14 14:45:24 +0000756</ul>
757
758<h3>1.8.4: Jan 13 2000</h3>
759<ul>
760 <li>bug fixes, reintroduced xmlNewGlobalNs(), fixed xmlNewNs()</li>
761 <li>all exit() call should have been removed from libxml</li>
762 <li>fixed a problem with INCLUDE_WINSOCK on WIN32 platform</li>
763 <li>added newDocFragment()</li>
Daniel Veillardf84f71f2000-01-05 19:54:23 +0000764</ul>
765
766<h3>1.8.3: Jan 5 2000</h3>
767<ul>
768 <li>a Push interface for the XML and HTML parsers</li>
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000769 <li>a shell-like interface to the document tree (try tester --shell :-)</li>
Daniel Veillarddbfd6411999-12-28 16:35:14 +0000770 <li>lots of bug fixes and improvement added over XMas hollidays</li>
Daniel Veillard437b87b2000-01-03 17:30:46 +0000771 <li>fixed the DTD parsing code to work with the xhtml DTD</li>
Daniel Veillardf84f71f2000-01-05 19:54:23 +0000772 <li>added xmlRemoveProp(), xmlRemoveID() and xmlRemoveRef()</li>
773 <li>Fixed bugs in xmlNewNs()</li>
Daniel Veillard437b87b2000-01-03 17:30:46 +0000774 <li>External entity loading code has been revamped, now it uses
Daniel Veillardf84f71f2000-01-05 19:54:23 +0000775 xmlLoadExternalEntity(), some fix on entities processing were added</li>
Daniel Veillard437b87b2000-01-03 17:30:46 +0000776 <li>cleaned up WIN32 includes of socket stuff</li>
Daniel Veillard5cb5ab81999-12-21 15:35:29 +0000777</ul>
778
779<h3>1.8.2: Dec 21 1999</h3>
780<ul>
Daniel Veillardb24054a1999-12-18 15:32:46 +0000781 <li>I got another problem with includes and C++, I hope this issue is fixed
782 for good this time</li>
Daniel Veillard5cb5ab81999-12-21 15:35:29 +0000783 <li>Added a few tree modification functions: xmlReplaceNode,
784 xmlAddPrevSibling, xmlAddNextSibling, xmlNodeSetName and
785 xmlDocSetRootElement</li>
786 <li>Tried to improve the HTML output with help from <a
787 href="mailto:clahey@umich.edu">Chris Lahey</a></li>
Daniel Veillarde4e51311999-12-18 15:32:46 +0000788</ul>
Daniel Veillardb24054a1999-12-18 15:32:46 +0000789
Daniel Veillarde4e51311999-12-18 15:32:46 +0000790<h3>1.8.1: Dec 18 1999</h3>
791<ul>
792 <li>various patches to avoid troubles when using libxml with C++ compilers
793 the "namespace" keyword and C escaping in include files</li>
794 <li>a problem in one of the core macros IS_CHAR was corrected</li>
795 <li>fixed a bug introduced in 1.8.0 breaking default namespace processing,
796 and more specifically the Dia application</li>
Daniel Veillard944b5ff1999-12-15 19:08:24 +0000797 <li>fixed a posteriori validation (validation after parsing, or by using a
798 Dtd not specified in the original document)</li>
Daniel Veillardb24054a1999-12-18 15:32:46 +0000799 <li>fixed a bug in</li>
Daniel Veillard10a2c651999-12-12 13:03:50 +0000800</ul>
801
802<h3>1.8.0: Dec 12 1999</h3>
803<ul>
804 <li>cleanup, especially memory wise</li>
805 <li>the parser should be more reliable, especially the HTML one, it should
806 not crash, whatever the input !</li>
807 <li>Integrated various patches, especially a speedup improvement for large
808 dataset from <a href="mailto:cnygard@bellatlantic.net">Carl Nygard</a>,
809 configure with --with-buffers to enable them.</li>
810 <li>attribute normalization, oops should have been added long ago !</li>
811 <li>attributes defaulted from Dtds should be available, xmlSetProp() now
812 does entities escapting by default.</li>
Daniel Veillard4c3a2031999-11-19 17:46:26 +0000813</ul>
Daniel Veillard35008381999-10-25 13:15:52 +0000814
815<h3>1.7.4: Oct 25 1999</h3>
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000816<ul>
Daniel Veillard35008381999-10-25 13:15:52 +0000817 <li>Lots of HTML improvement</li>
818 <li>Fixed some errors when saving both XML and HTML</li>
819 <li>More examples, the regression tests should now look clean</li>
820 <li>Fixed a bug with contiguous charref</li>
821</ul>
822
823<h3>1.7.3: Sep 29 1999</h3>
824<ul>
825 <li>portability problems fixed</li>
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000826 <li>snprintf was used unconditionnally, leading to link problems on system
Daniel Veillard35008381999-10-25 13:15:52 +0000827 were it's not available, fixed</li>
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000828</ul>
829
830<h3>1.7.1: Sep 24 1999</h3>
831<ul>
832 <li>The basic type for strings manipulated by libxml has been renamed in
833 1.7.1 from <strong>CHAR</strong> to <strong>xmlChar</strong>. The reason
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000834 is that CHAR was conflicting with a predefined type on Windows. However
835 on non WIN32 environment, compatibility is provided by the way of a
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000836 <strong>#define </strong>.</li>
837 <li>Changed another error : the use of a structure field called errno, and
838 leading to troubles on platforms where it's a macro</li>
839</ul>
840
841<h3>1.7.0: sep 23 1999</h3>
842<ul>
843 <li>Added the ability to fetch remote DTD or parsed entities, see the <a
Daniel Veillard9cb5ff42001-01-29 08:22:21 +0000844 href="html/libxml-nanohttp.html">nanohttp</a> module.</li>
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000845 <li>Added an errno to report errors by another mean than a simple printf
846 like callback</li>
847 <li>Finished ID/IDREF support and checking when validation</li>
848 <li>Serious memory leaks fixed (there is now a <a
Daniel Veillard9cb5ff42001-01-29 08:22:21 +0000849 href="html/libxml-xmlmemory.html">memory wrapper</a> module)</li>
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000850 <li>Improvement of <a href="http://www.w3.org/TR/xpath">XPath</a>
851 implementation</li>
852 <li>Added an HTML parser front-end</li>
853</ul>
854
855<h2><a name="XML">XML</a></h2>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000856
Daniel Veillard402e8c82000-02-29 22:57:47 +0000857<p><a href="http://www.w3.org/TR/REC-xml">XML is a standard</a> for
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000858markup-based structured documents. Here is <a name="example">an example XML
859document</a>:</p>
Daniel Veillard60979bd2000-07-10 12:17:33 +0000860<pre>&lt;?xml version="1.0"?&gt;
861&lt;EXAMPLE prop1="gnome is great" prop2="&amp;amp; linux too"&gt;
862 &lt;head&gt;
863 &lt;title&gt;Welcome to Gnome&lt;/title&gt;
864 &lt;/head&gt;
865 &lt;chapter&gt;
866 &lt;title&gt;The Linux adventure&lt;/title&gt;
867 &lt;p&gt;bla bla bla ...&lt;/p&gt;
868 &lt;image href="linus.gif"/&gt;
869 &lt;p&gt;...&lt;/p&gt;
870 &lt;/chapter&gt;
871&lt;/EXAMPLE&gt;</pre>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000872
Daniel Veillard402e8c82000-02-29 22:57:47 +0000873<p>The first line specifies that it's an XML document and gives useful
874information about its encoding. Then the document is a text format whose
875structure is specified by tags between brackets. <strong>Each tag opened has
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000876to be closed</strong>. XML is pedantic about this. However, if a tag is empty
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000877(no content), a single tag can serve as both the opening and closing tag if
878it ends with <code>/&gt;</code> rather than with <code>&gt;</code>. Note
879that, for example, the image tag has no content (just an attribute) and is
880closed by ending the tag with <code>/&gt;</code>.</p>
Daniel Veillardccb09631998-10-27 06:21:04 +0000881
Daniel Veillard402e8c82000-02-29 22:57:47 +0000882<p>XML can be applied sucessfully to a wide range of uses, from long term
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000883structured document maintenance (where it follows the steps of SGML) to
884simple data encoding mechanisms like configuration file formatting (glade),
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000885spreadsheets (gnumeric), or even shorter lived documents such as WebDAV where
886it is used to encode remote calls between a client and a server.</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000887
Daniel Veillard82687162001-01-22 15:32:01 +0000888<h2><a name="XSLT">XSLT</a></h2>
889
Daniel Veillard6e6a6cc2001-02-15 15:55:44 +0000890<p>Check <a href="http://xmlsoft.org/XSLT">the separate libxslt page</a></p>
891
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000892<p><a href="http://www.w3.org/TR/xslt">XSL Transformations</a>, is a
893language for transforming XML documents into other XML documents (or
894HTML/textual output).</p>
Daniel Veillard82687162001-01-22 15:32:01 +0000895
896<p>A separate library called libxslt is being built on top of libxml2. This
897module "libxslt" can be found in the Gnome CVS base too.</p>
898
Daniel Veillard383b1472001-01-23 11:39:52 +0000899<p>You can check the <a
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000900href="http://cvs.gnome.org/lxr/source/libxslt/FEATURES">features</a>
901supported and the progresses on the <a
Daniel Veillard82687162001-01-22 15:32:01 +0000902href="http://cvs.gnome.org/lxr/source/libxslt/ChangeLog">Changelog</a></p>
903
Daniel Veillard4540be42000-08-19 16:40:28 +0000904<h2>An overview of libxml architecture</h2>
905
Daniel Veillardec70e912001-02-26 20:10:45 +0000906<p>Libxml is made of multiple components; some of them are optional, and most
907of the block interfaces are public. The main components are:</p>
Daniel Veillard4540be42000-08-19 16:40:28 +0000908<ul>
909 <li>an Input/Output layer</li>
Daniel Veillard91e9d582001-02-26 07:31:12 +0000910 <li>FTP and HTTP client layers (optional)</li>
Daniel Veillard4540be42000-08-19 16:40:28 +0000911 <li>an Internationalization layer managing the encodings support</li>
Daniel Veillard91e9d582001-02-26 07:31:12 +0000912 <li>a URI module</li>
Daniel Veillard4540be42000-08-19 16:40:28 +0000913 <li>the XML parser and its basic SAX interface</li>
Daniel Veillard91e9d582001-02-26 07:31:12 +0000914 <li>an HTML parser using the same SAX interface (optional)</li>
Daniel Veillard4540be42000-08-19 16:40:28 +0000915 <li>a SAX tree module to build an in-memory DOM representation</li>
916 <li>a tree module to manipulate the DOM representation</li>
Daniel Veillard91e9d582001-02-26 07:31:12 +0000917 <li>a validation module using the DOM representation (optional)</li>
Daniel Veillard4540be42000-08-19 16:40:28 +0000918 <li>an XPath module for global lookup in a DOM representation
Daniel Veillard91e9d582001-02-26 07:31:12 +0000919 (optional)</li>
920 <li>a debug module (optional)</li>
Daniel Veillard4540be42000-08-19 16:40:28 +0000921</ul>
922
923<p>Graphically this gives the following:</p>
924
925<p><img src="libxml.gif" alt="a graphical view of the various"></p>
926
927<p></p>
928
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000929<h2><a name="tree">The tree output</a></h2>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000930
931<p>The parser returns a tree built during the document analysis. The value
Daniel Veillard402e8c82000-02-29 22:57:47 +0000932returned is an <strong>xmlDocPtr</strong> (i.e., a pointer to an
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000933<strong>xmlDoc</strong> structure). This structure contains information such
Daniel Veillard306be992000-07-03 12:38:45 +0000934as the file name, the document type, and a <strong>children</strong> pointer
935which is the root of the document (or more exactly the first child under the
936root which is the document). The tree is made of <strong>xmlNode</strong>s,
Daniel Veillard91e9d582001-02-26 07:31:12 +0000937chained in double-linked lists of siblings and with a children&lt;-&gt;parent
Daniel Veillard306be992000-07-03 12:38:45 +0000938relationship. An xmlNode can also carry properties (a chain of xmlAttr
939structures). An attribute may have a value which is a list of TEXT or
940ENTITY_REF nodes.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000941
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000942<p>Here is an example (erroneous with respect to the XML spec since there
943should be only one ELEMENT under the root):</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000944
945<p><img src="structure.gif" alt=" structure.gif "></p>
946
947<p>In the source package there is a small program (not installed by default)
Daniel Veillard361d8452000-04-03 19:48:13 +0000948called <strong>xmllint</strong> which parses XML files given as argument and
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000949prints them back as parsed. This is useful for detecting errors both in XML
950code and in the XML parser itself. It has an option <strong>--debug</strong>
Daniel Veillard91e9d582001-02-26 07:31:12 +0000951which prints the actual in-memory structure of the document; here is the
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000952result with the <a href="#example">example</a> given before:</p>
Daniel Veillard10c6a8f1998-10-28 01:00:12 +0000953<pre>DOCUMENT
954version=1.0
955standalone=true
956 ELEMENT EXAMPLE
957 ATTRIBUTE prop1
958 TEXT
959 content=gnome is great
960 ATTRIBUTE prop2
961 ENTITY_REF
962 TEXT
Daniel Veillard0142b842000-01-14 14:45:24 +0000963 content= linux too
Daniel Veillard402e8c82000-02-29 22:57:47 +0000964 ELEMENT head
Daniel Veillard10c6a8f1998-10-28 01:00:12 +0000965 ELEMENT title
Daniel Veillard25940b71998-10-29 05:51:30 +0000966 TEXT
967 content=Welcome to Gnome
Daniel Veillard10c6a8f1998-10-28 01:00:12 +0000968 ELEMENT chapter
969 ELEMENT title
Daniel Veillard25940b71998-10-29 05:51:30 +0000970 TEXT
971 content=The Linux adventure
Daniel Veillard10c6a8f1998-10-28 01:00:12 +0000972 ELEMENT p
Daniel Veillard25940b71998-10-29 05:51:30 +0000973 TEXT
974 content=bla bla bla ...
Daniel Veillard10c6a8f1998-10-28 01:00:12 +0000975 ELEMENT image
976 ATTRIBUTE href
977 TEXT
978 content=linus.gif
979 ELEMENT p
Daniel Veillard25940b71998-10-29 05:51:30 +0000980 TEXT
981 content=...</pre>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000982
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000983<p>This should be useful for learning the internal representation model.</p>
Daniel Veillardccb09631998-10-27 06:21:04 +0000984
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000985<h2><a name="interface">The SAX interface</a></h2>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000986
Daniel Veillard402e8c82000-02-29 22:57:47 +0000987<p>Sometimes the DOM tree output is just too large to fit reasonably into
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000988memory. In that case (and if you don't expect to save back the XML document
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000989loaded using libxml), it's better to use the SAX interface of libxml. SAX is
990a <strong>callback-based interface</strong> to the parser. Before parsing,
991the application layer registers a customized set of callbacks which are
992called by the library as it progresses through the XML input.</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000993
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000994<p>To get more detailed step-by-step guidance on using the SAX interface of
Daniel Veillard4540be42000-08-19 16:40:28 +0000995libxml, see the <a
996href="http://www.daa.com.au/~james/gnome/xml-sax/xml-sax.html">nice
997documentation</a>.written by <a href="mailto:james@daa.com.au">James
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000998Henstridge</a>.</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000999
1000<p>You can debug the SAX behaviour by using the <strong>testSAX</strong>
1001program located in the gnome-xml module (it's usually not shipped in the
Daniel Veillard88f00ae2000-03-02 00:15:55 +00001002binary packages of libxml, but you can find it in the tar source
Daniel Veillard402e8c82000-02-29 22:57:47 +00001003distribution). Here is the sequence of callbacks that would be reported by
Daniel Veillard88f00ae2000-03-02 00:15:55 +00001004testSAX when parsing the example XML document shown earlier:</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +00001005<pre>SAX.setDocumentLocator()
1006SAX.startDocument()
1007SAX.getEntity(amp)
1008SAX.startElement(EXAMPLE, prop1='gnome is great', prop2='&amp;amp; linux too')
1009SAX.characters( , 3)
1010SAX.startElement(head)
1011SAX.characters( , 4)
1012SAX.startElement(title)
1013SAX.characters(Welcome to Gnome, 16)
1014SAX.endElement(title)
1015SAX.characters( , 3)
1016SAX.endElement(head)
1017SAX.characters( , 3)
1018SAX.startElement(chapter)
1019SAX.characters( , 4)
1020SAX.startElement(title)
1021SAX.characters(The Linux adventure, 19)
1022SAX.endElement(title)
1023SAX.characters( , 4)
1024SAX.startElement(p)
1025SAX.characters(bla bla bla ..., 15)
1026SAX.endElement(p)
1027SAX.characters( , 4)
1028SAX.startElement(image, href='linus.gif')
1029SAX.endElement(image)
1030SAX.characters( , 4)
1031SAX.startElement(p)
1032SAX.characters(..., 3)
1033SAX.endElement(p)
1034SAX.characters( , 3)
1035SAX.endElement(chapter)
1036SAX.characters( , 1)
1037SAX.endElement(EXAMPLE)
1038SAX.endDocument()</pre>
1039
Daniel Veillardec70e912001-02-26 20:10:45 +00001040<p>Most of the other interfaces of libxml are based on the DOM tree-building
1041facility, so nearly everything up to the end of this document presupposes the
1042use of the standard DOM tree build. Note that the DOM tree itself is built by
1043a set of registered default callbacks, without internal specific
1044interface.</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +00001045
Daniel Veillard2f4dfc41999-09-24 14:03:48 +00001046<h2><a name="library">The XML library interfaces</a></h2>
Daniel Veillardb05deb71999-08-10 19:04:08 +00001047
1048<p>This section is directly intended to help programmers getting bootstrapped
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +00001049using the XML library from the C language. It is not intended to be
1050extensive. I hope the automatically generated documents will provide the
1051completeness required, but as a separate set of documents. The interfaces of
1052the XML library are by principle low level, there is nearly zero abstraction.
1053Those interested in a higher level API should <a href="#DOM">look at
1054DOM</a>.</p>
Daniel Veillardccb09631998-10-27 06:21:04 +00001055
Daniel Veillard9cb5ff42001-01-29 08:22:21 +00001056<p>The <a href="html/libxml-parser.html">parser interfaces for XML</a> are
1057separated from the <a href="html/libxml-htmlparser.html">HTML parser
Daniel Veillard88f00ae2000-03-02 00:15:55 +00001058interfaces</a>. Let's have a look at how the XML parser can be called:</p>
Daniel Veillard0142b842000-01-14 14:45:24 +00001059
Daniel Veillard88f00ae2000-03-02 00:15:55 +00001060<h3><a name="Invoking">Invoking the parser : the pull method</a></h3>
Daniel Veillardb05deb71999-08-10 19:04:08 +00001061
Daniel Veillard88f00ae2000-03-02 00:15:55 +00001062<p>Usually, the first thing to do is to read an XML input. The parser accepts
1063documents either from in-memory strings or from files. The functions are
Daniel Veillardb05deb71999-08-10 19:04:08 +00001064defined in "parser.h":</p>
Daniel Veillard10c6a8f1998-10-28 01:00:12 +00001065<dl>
Daniel Veillardb05deb71999-08-10 19:04:08 +00001066 <dt><code>xmlDocPtr xmlParseMemory(char *buffer, int size);</code></dt>
Daniel Veillard88f00ae2000-03-02 00:15:55 +00001067 <dd><p>Parse a null-terminated string containing the document.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +00001068 </dd>
Daniel Veillard10c6a8f1998-10-28 01:00:12 +00001069</dl>
1070<dl>
Daniel Veillardb05deb71999-08-10 19:04:08 +00001071 <dt><code>xmlDocPtr xmlParseFile(const char *filename);</code></dt>
Daniel Veillardf13e1ed2000-03-06 07:41:49 +00001072 <dd><p>Parse an XML document contained in a (possibly compressed)
1073 file.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +00001074 </dd>
Daniel Veillard10c6a8f1998-10-28 01:00:12 +00001075</dl>
Daniel Veillardb05deb71999-08-10 19:04:08 +00001076
Daniel Veillard88f00ae2000-03-02 00:15:55 +00001077<p>The parser returns a pointer to the document structure (or NULL in case of
Daniel Veillard10c6a8f1998-10-28 01:00:12 +00001078failure).</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +00001079
Daniel Veillard88f00ae2000-03-02 00:15:55 +00001080<h3 id="Invoking1">Invoking the parser: the push method</h3>
Daniel Veillard0142b842000-01-14 14:45:24 +00001081
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +00001082<p>In order for the application to keep the control when the document is
1083being fetched (which is common for GUI based programs) libxml provides a push
Daniel Veillard88f00ae2000-03-02 00:15:55 +00001084interface, too, as of version 1.8.3. Here are the interface functions:</p>
Daniel Veillard0142b842000-01-14 14:45:24 +00001085<pre>xmlParserCtxtPtr xmlCreatePushParserCtxt(xmlSAXHandlerPtr sax,
1086 void *user_data,
1087 const char *chunk,
1088 int size,
1089 const char *filename);
1090int xmlParseChunk (xmlParserCtxtPtr ctxt,
1091 const char *chunk,
1092 int size,
1093 int terminate);</pre>
1094
Daniel Veillard88f00ae2000-03-02 00:15:55 +00001095<p>and here is a simple example showing how to use the interface:</p>
Daniel Veillard0142b842000-01-14 14:45:24 +00001096<pre> FILE *f;
1097
1098 f = fopen(filename, "r");
1099 if (f != NULL) {
1100 int res, size = 1024;
1101 char chars[1024];
1102 xmlParserCtxtPtr ctxt;
1103
1104 res = fread(chars, 1, 4, f);
Daniel Veillard60979bd2000-07-10 12:17:33 +00001105 if (res &gt; 0) {
Daniel Veillard0142b842000-01-14 14:45:24 +00001106 ctxt = xmlCreatePushParserCtxt(NULL, NULL,
1107 chars, res, filename);
Daniel Veillard60979bd2000-07-10 12:17:33 +00001108 while ((res = fread(chars, 1, size, f)) &gt; 0) {
Daniel Veillard0142b842000-01-14 14:45:24 +00001109 xmlParseChunk(ctxt, chars, res, 0);
1110 }
1111 xmlParseChunk(ctxt, chars, 0, 1);
Daniel Veillard60979bd2000-07-10 12:17:33 +00001112 doc = ctxt-&gt;myDoc;
Daniel Veillard0142b842000-01-14 14:45:24 +00001113 xmlFreeParserCtxt(ctxt);
1114 }
1115 }</pre>
1116
Daniel Veillardec70e912001-02-26 20:10:45 +00001117<p>The HTML parser embedded into libxml also has a push interface; the
1118functions are just prefixed by "html" rather than "xml".</p>
Daniel Veillard0142b842000-01-14 14:45:24 +00001119
1120<h3 id="Invoking2">Invoking the parser: the SAX interface</h3>
1121
Daniel Veillardec70e912001-02-26 20:10:45 +00001122<p>The tree-building interface makes the parser memory-hungry, first loading
1123the document in memory and then building the tree itself. Reading a document
1124without building the tree is possible using the SAX interfaces (see SAX.h and
1125<a href="http://www.daa.com.au/~james/gnome/xml-sax/xml-sax.html">James
Daniel Veillard88f00ae2000-03-02 00:15:55 +00001126Henstridge's documentation</a>). Note also that the push interface can be
Daniel Veillard91e9d582001-02-26 07:31:12 +00001127limited to SAX: just use the two first arguments of
Daniel Veillard0142b842000-01-14 14:45:24 +00001128<code>xmlCreatePushParserCtxt()</code>.</p>
Daniel Veillardccb09631998-10-27 06:21:04 +00001129
Daniel Veillard2f4dfc41999-09-24 14:03:48 +00001130<h3><a name="Building">Building a tree from scratch</a></h3>
Daniel Veillardb05deb71999-08-10 19:04:08 +00001131
1132<p>The other way to get an XML tree in memory is by building it. Basically
Daniel Veillardf13e1ed2000-03-06 07:41:49 +00001133there is a set of functions dedicated to building new elements. (These are
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +00001134also described in &lt;libxml/tree.h&gt;.) For example, here is a piece of
1135code that produces the XML document used in the previous examples:</p>
Daniel Veillard60979bd2000-07-10 12:17:33 +00001136<pre> #include &lt;libxml/tree.h&gt;
Daniel Veillard361d8452000-04-03 19:48:13 +00001137 xmlDocPtr doc;
Daniel Veillard25940b71998-10-29 05:51:30 +00001138 xmlNodePtr tree, subtree;
1139
1140 doc = xmlNewDoc("1.0");
Daniel Veillard60979bd2000-07-10 12:17:33 +00001141 doc-&gt;children = xmlNewDocNode(doc, NULL, "EXAMPLE", NULL);
1142 xmlSetProp(doc-&gt;children, "prop1", "gnome is great");
1143 xmlSetProp(doc-&gt;children, "prop2", "&amp; linux too");
1144 tree = xmlNewChild(doc-&gt;children, NULL, "head", NULL);
Daniel Veillard25940b71998-10-29 05:51:30 +00001145 subtree = xmlNewChild(tree, NULL, "title", "Welcome to Gnome");
Daniel Veillard60979bd2000-07-10 12:17:33 +00001146 tree = xmlNewChild(doc-&gt;children, NULL, "chapter", NULL);
Daniel Veillard25940b71998-10-29 05:51:30 +00001147 subtree = xmlNewChild(tree, NULL, "title", "The Linux adventure");
1148 subtree = xmlNewChild(tree, NULL, "p", "bla bla bla ...");
1149 subtree = xmlNewChild(tree, NULL, "image", NULL);
1150 xmlSetProp(subtree, "href", "linus.gif");</pre>
Daniel Veillardb05deb71999-08-10 19:04:08 +00001151
1152<p>Not really rocket science ...</p>
Daniel Veillard25940b71998-10-29 05:51:30 +00001153
Daniel Veillard2f4dfc41999-09-24 14:03:48 +00001154<h3><a name="Traversing">Traversing the tree</a></h3>
Daniel Veillardb05deb71999-08-10 19:04:08 +00001155
Daniel Veillard9cb5ff42001-01-29 08:22:21 +00001156<p>Basically by <a href="html/libxml-tree.html">including "tree.h"</a> your
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +00001157code has access to the internal structure of all the elements of the tree.
1158The names should be somewhat simple like <strong>parent</strong>,
Daniel Veillard306be992000-07-03 12:38:45 +00001159<strong>children</strong>, <strong>next</strong>, <strong>prev</strong>,
Daniel Veillard88f00ae2000-03-02 00:15:55 +00001160<strong>properties</strong>, etc... For example, still with the previous
Daniel Veillard0142b842000-01-14 14:45:24 +00001161example:</p>
Daniel Veillard60979bd2000-07-10 12:17:33 +00001162<pre><code>doc-&gt;children-&gt;children-&gt;children</code></pre>
Daniel Veillardb05deb71999-08-10 19:04:08 +00001163
1164<p>points to the title element,</p>
Daniel Veillard91e9d582001-02-26 07:31:12 +00001165<pre>doc-&gt;children-&gt;children-&gt;next-&gt;children-&gt;children</pre>
Daniel Veillardb05deb71999-08-10 19:04:08 +00001166
Daniel Veillardf13e1ed2000-03-06 07:41:49 +00001167<p>points to the text node containing the chapter title "The Linux
1168adventure".</p>
Daniel Veillard10c6a8f1998-10-28 01:00:12 +00001169
Daniel Veillardb24054a1999-12-18 15:32:46 +00001170<p><strong>NOTE</strong>: XML allows <em>PI</em>s and <em>comments</em> to be
Daniel Veillard60979bd2000-07-10 12:17:33 +00001171present before the document root, so <code>doc-&gt;children</code> may point
Daniel Veillard91e9d582001-02-26 07:31:12 +00001172to an element which is not the document Root Element; a function
Daniel Veillard5cb5ab81999-12-21 15:35:29 +00001173<code>xmlDocGetRootElement()</code> was added for this purpose.</p>
Daniel Veillardb24054a1999-12-18 15:32:46 +00001174
Daniel Veillard2f4dfc41999-09-24 14:03:48 +00001175<h3><a name="Modifying">Modifying the tree</a></h3>
Daniel Veillardb05deb71999-08-10 19:04:08 +00001176
Daniel Veillard88f00ae2000-03-02 00:15:55 +00001177<p>Functions are provided for reading and writing the document content. Here
Daniel Veillard9cb5ff42001-01-29 08:22:21 +00001178is an excerpt from the <a href="html/libxml-tree.html">tree API</a>:</p>
Daniel Veillard25940b71998-10-29 05:51:30 +00001179<dl>
Daniel Veillarddd6b3671999-09-23 22:19:22 +00001180 <dt><code>xmlAttrPtr xmlSetProp(xmlNodePtr node, const xmlChar *name, const
1181 xmlChar *value);</code></dt>
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +00001182 <dd><p>This sets (or changes) an attribute carried by an ELEMENT node.
1183 The value can be NULL.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +00001184 </dd>
Daniel Veillard25940b71998-10-29 05:51:30 +00001185</dl>
1186<dl>
Daniel Veillarddd6b3671999-09-23 22:19:22 +00001187 <dt><code>const xmlChar *xmlGetProp(xmlNodePtr node, const xmlChar
Daniel Veillardb05deb71999-08-10 19:04:08 +00001188 *name);</code></dt>
Daniel Veillardc92c3042000-09-29 02:42:04 +00001189 <dd><p>This function returns a pointer to new copy of the property
1190 content. Note that the user must deallocate the result.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +00001191 </dd>
Daniel Veillard25940b71998-10-29 05:51:30 +00001192</dl>
Daniel Veillardb05deb71999-08-10 19:04:08 +00001193
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +00001194<p>Two functions are provided for reading and writing the text associated
1195with elements:</p>
Daniel Veillard25940b71998-10-29 05:51:30 +00001196<dl>
Daniel Veillarddd6b3671999-09-23 22:19:22 +00001197 <dt><code>xmlNodePtr xmlStringGetNodeList(xmlDocPtr doc, const xmlChar
Daniel Veillardb05deb71999-08-10 19:04:08 +00001198 *value);</code></dt>
Daniel Veillardec70e912001-02-26 20:10:45 +00001199 <dd><p>This function takes an "external" string and converts it to one
1200 text node or possibly to a list of entity and text nodes. All
1201 non-predefined entity references like &amp;Gnome; will be stored
1202 internally as entity nodes, hence the result of the function may not be
1203 a single node.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +00001204 </dd>
Daniel Veillard25940b71998-10-29 05:51:30 +00001205</dl>
1206<dl>
Daniel Veillarddd6b3671999-09-23 22:19:22 +00001207 <dt><code>xmlChar *xmlNodeListGetString(xmlDocPtr doc, xmlNodePtr list, int
Daniel Veillardb05deb71999-08-10 19:04:08 +00001208 inLine);</code></dt>
Daniel Veillardf13e1ed2000-03-06 07:41:49 +00001209 <dd><p>This function is the inverse of
1210 <code>xmlStringGetNodeList()</code>. It generates a new string
1211 containing the content of the text and entity nodes. Note the extra
1212 argument inLine. If this argument is set to 1, the function will expand
1213 entity references. For example, instead of returning the &amp;Gnome;
1214 XML encoding in the string, it will substitute it with its value (say,
Daniel Veillard91e9d582001-02-26 07:31:12 +00001215 "GNU Network Object Model Environment").</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +00001216 </dd>
Daniel Veillard25940b71998-10-29 05:51:30 +00001217</dl>
Daniel Veillard10c6a8f1998-10-28 01:00:12 +00001218
Daniel Veillard2f4dfc41999-09-24 14:03:48 +00001219<h3><a name="Saving">Saving a tree</a></h3>
Daniel Veillardb05deb71999-08-10 19:04:08 +00001220
1221<p>Basically 3 options are possible:</p>
Daniel Veillard25940b71998-10-29 05:51:30 +00001222<dl>
Daniel Veillarddd6b3671999-09-23 22:19:22 +00001223 <dt><code>void xmlDocDumpMemory(xmlDocPtr cur, xmlChar**mem, int
Daniel Veillardb05deb71999-08-10 19:04:08 +00001224 *size);</code></dt>
Daniel Veillard88f00ae2000-03-02 00:15:55 +00001225 <dd><p>Returns a buffer into which the document has been saved.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +00001226 </dd>
Daniel Veillard25940b71998-10-29 05:51:30 +00001227</dl>
1228<dl>
Daniel Veillardb05deb71999-08-10 19:04:08 +00001229 <dt><code>extern void xmlDocDump(FILE *f, xmlDocPtr doc);</code></dt>
Daniel Veillard88f00ae2000-03-02 00:15:55 +00001230 <dd><p>Dumps a document to an open file descriptor.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +00001231 </dd>
Daniel Veillard25940b71998-10-29 05:51:30 +00001232</dl>
1233<dl>
Daniel Veillardb05deb71999-08-10 19:04:08 +00001234 <dt><code>int xmlSaveFile(const char *filename, xmlDocPtr cur);</code></dt>
Daniel Veillardf13e1ed2000-03-06 07:41:49 +00001235 <dd><p>Saves the document to a file. In this case, the compression
1236 interface is triggered if it has been turned on.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +00001237 </dd>
Daniel Veillard25940b71998-10-29 05:51:30 +00001238</dl>
Daniel Veillard10c6a8f1998-10-28 01:00:12 +00001239
Daniel Veillard2f4dfc41999-09-24 14:03:48 +00001240<h3><a name="Compressio">Compression</a></h3>
Daniel Veillardb05deb71999-08-10 19:04:08 +00001241
Daniel Veillard88f00ae2000-03-02 00:15:55 +00001242<p>The library transparently handles compression when doing file-based
Daniel Veillardf13e1ed2000-03-06 07:41:49 +00001243accesses. The level of compression on saves can be turned on either globally
1244or individually for one file:</p>
Daniel Veillard25940b71998-10-29 05:51:30 +00001245<dl>
Daniel Veillardb05deb71999-08-10 19:04:08 +00001246 <dt><code>int xmlGetDocCompressMode (xmlDocPtr doc);</code></dt>
Daniel Veillard88f00ae2000-03-02 00:15:55 +00001247 <dd><p>Gets the document compression ratio (0-9).</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +00001248 </dd>
Daniel Veillard25940b71998-10-29 05:51:30 +00001249</dl>
1250<dl>
Daniel Veillardb05deb71999-08-10 19:04:08 +00001251 <dt><code>void xmlSetDocCompressMode (xmlDocPtr doc, int mode);</code></dt>
Daniel Veillard88f00ae2000-03-02 00:15:55 +00001252 <dd><p>Sets the document compression ratio.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +00001253 </dd>
Daniel Veillard25940b71998-10-29 05:51:30 +00001254</dl>
1255<dl>
Daniel Veillardb05deb71999-08-10 19:04:08 +00001256 <dt><code>int xmlGetCompressMode(void);</code></dt>
Daniel Veillard88f00ae2000-03-02 00:15:55 +00001257 <dd><p>Gets the default compression ratio.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +00001258 </dd>
Daniel Veillard25940b71998-10-29 05:51:30 +00001259</dl>
1260<dl>
Daniel Veillardb05deb71999-08-10 19:04:08 +00001261 <dt><code>void xmlSetCompressMode(int mode);</code></dt>
Daniel Veillard88f00ae2000-03-02 00:15:55 +00001262 <dd><p>Sets the default compression ratio.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +00001263 </dd>
Daniel Veillard25940b71998-10-29 05:51:30 +00001264</dl>
1265
Daniel Veillard2f4dfc41999-09-24 14:03:48 +00001266<h2><a name="Entities">Entities or no entities</a></h2>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +00001267
Daniel Veillard88f00ae2000-03-02 00:15:55 +00001268<p>Entities in principle are similar to simple C macros. An entity defines an
1269abbreviation for a given string that you can reuse many times throughout the
1270content of your document. Entities are especially useful when a given string
Daniel Veillardf13e1ed2000-03-06 07:41:49 +00001271may occur frequently within a document, or to confine the change needed to a
1272document to a restricted area in the internal subset of the document (at the
1273beginning). Example:</p>
Daniel Veillard60979bd2000-07-10 12:17:33 +00001274<pre>1 &lt;?xml version="1.0"?&gt;
Daniel Veillardc8eab3a1999-09-04 18:27:23 +000012752 &lt;!DOCTYPE EXAMPLE SYSTEM "example.dtd" [
Daniel Veillard60979bd2000-07-10 12:17:33 +000012763 &lt;!ENTITY xml "Extensible Markup Language"&gt;
12774 ]&gt;
12785 &lt;EXAMPLE&gt;
Daniel Veillardc8eab3a1999-09-04 18:27:23 +000012796 &amp;xml;
Daniel Veillard60979bd2000-07-10 12:17:33 +000012807 &lt;/EXAMPLE&gt;</pre>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +00001281
1282<p>Line 3 declares the xml entity. Line 6 uses the xml entity, by prefixing
Daniel Veillard91e9d582001-02-26 07:31:12 +00001283its name with '&amp;' and following it by ';' without any spaces added. There
Daniel Veillard88f00ae2000-03-02 00:15:55 +00001284are 5 predefined entities in libxml allowing you to escape charaters with
Daniel Veillardc8eab3a1999-09-04 18:27:23 +00001285predefined meaning in some parts of the xml document content:
Daniel Veillard88f00ae2000-03-02 00:15:55 +00001286<strong>&amp;lt;</strong> for the character '&lt;', <strong>&amp;gt;</strong>
Daniel Veillard60979bd2000-07-10 12:17:33 +00001287for the character '&gt;', <strong>&amp;apos;</strong> for the character ''',
Daniel Veillard88f00ae2000-03-02 00:15:55 +00001288<strong>&amp;quot;</strong> for the character '"', and
1289<strong>&amp;amp;</strong> for the character '&amp;'.</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +00001290
1291<p>One of the problems related to entities is that you may want the parser to
Daniel Veillardf13e1ed2000-03-06 07:41:49 +00001292substitute an entity's content so that you can see the replacement text in
1293your application. Or you may prefer to keep entity references as such in the
1294content to be able to save the document back without losing this usually
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +00001295precious information (if the user went through the pain of explicitly
1296defining entities, he may have a a rather negative attitude if you blindly
1297susbtitute them as saving time). The <a
Daniel Veillard9cb5ff42001-01-29 08:22:21 +00001298href="html/libxml-parser.html#XMLSUBSTITUTEENTITIESDEFAULT">xmlSubstituteEntitiesDefault()</a>
Daniel Veillard88f00ae2000-03-02 00:15:55 +00001299function allows you to check and change the behaviour, which is to not
1300substitute entities by default.</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +00001301
1302<p>Here is the DOM tree built by libxml for the previous document in the
1303default case:</p>
Daniel Veillard60979bd2000-07-10 12:17:33 +00001304<pre>/gnome/src/gnome-xml -&gt; ./xmllint --debug test/ent1
Daniel Veillardc8eab3a1999-09-04 18:27:23 +00001305DOCUMENT
1306version=1.0
1307 ELEMENT EXAMPLE
1308 TEXT
1309 content=
1310 ENTITY_REF
1311 INTERNAL_GENERAL_ENTITY xml
1312 content=Extensible Markup Language
1313 TEXT
1314 content=</pre>
1315
1316<p>And here is the result when substituting entities:</p>
Daniel Veillard60979bd2000-07-10 12:17:33 +00001317<pre>/gnome/src/gnome-xml -&gt; ./tester --debug --noent test/ent1
Daniel Veillardc8eab3a1999-09-04 18:27:23 +00001318DOCUMENT
1319version=1.0
1320 ELEMENT EXAMPLE
1321 TEXT
1322 content= Extensible Markup Language</pre>
1323
Daniel Veillard88f00ae2000-03-02 00:15:55 +00001324<p>So, entities or no entities? Basically, it depends on your use case. I
1325suggest that you keep the non-substituting default behaviour and avoid using
Daniel Veillardc8eab3a1999-09-04 18:27:23 +00001326entities in your XML document or data if you are not willing to handle the
1327entity references elements in the DOM tree.</p>
1328
Daniel Veillard91e9d582001-02-26 07:31:12 +00001329<p>Note that at save time libxml enforces the conversion of the predefined
Daniel Veillardc8eab3a1999-09-04 18:27:23 +00001330entities where necessary to prevent well-formedness problems, and will also
Daniel Veillard91e9d582001-02-26 07:31:12 +00001331transparently replace those with chars (i.e. it will not generate entity
Daniel Veillard88f00ae2000-03-02 00:15:55 +00001332reference elements in the DOM tree or call the reference() SAX callback when
Daniel Veillardc8eab3a1999-09-04 18:27:23 +00001333finding them in the input).</p>
1334
Daniel Veillard7b9c4b72000-08-25 16:26:50 +00001335<p><span style="background-color: #FF0000">WARNING</span>: handling entities
Daniel Veillard91e9d582001-02-26 07:31:12 +00001336on top of the libxml SAX interface is difficult!!! If you plan to use
Daniel Veillard7b9c4b72000-08-25 16:26:50 +00001337non-predefined entities in your documents, then the learning cuvre to handle
Daniel Veillard91e9d582001-02-26 07:31:12 +00001338then using the SAX API may be long. If you plan to use complex documents, I
Daniel Veillard7b9c4b72000-08-25 16:26:50 +00001339strongly suggest you consider using the DOM interface instead and let libxml
Daniel Veillard8c6d6af2000-08-25 17:14:13 +00001340deal with the complexity rather than trying to do it yourself.</p>
Daniel Veillard7b9c4b72000-08-25 16:26:50 +00001341
Daniel Veillard2f4dfc41999-09-24 14:03:48 +00001342<h2><a name="Namespaces">Namespaces</a></h2>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +00001343
Daniel Veillardec303412000-03-24 13:41:54 +00001344<p>The libxml library implements <a
1345href="http://www.w3.org/TR/REC-xml-names/">XML namespaces</a> support by
1346recognizing namespace contructs in the input, and does namespace lookup
1347automatically when building the DOM tree. A namespace declaration is
1348associated with an in-memory structure and all elements or attributes within
1349that namespace point to it. Hence testing the namespace is a simple and fast
1350equality operation at the user level.</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +00001351
Daniel Veillardf13e1ed2000-03-06 07:41:49 +00001352<p>I suggest that people using libxml use a namespace, and declare it in the
1353root element of their document as the default namespace. Then they don't need
1354to use the prefix in the content but we will have a basis for future semantic
Daniel Veillard91e9d582001-02-26 07:31:12 +00001355refinement and merging of data from different sources. This doesn't increase
Daniel Veillardec70e912001-02-26 20:10:45 +00001356the size of the XML output significantly, but significantly increases its
1357value in the long-term. Example:</p>
Daniel Veillard60979bd2000-07-10 12:17:33 +00001358<pre>&lt;mydoc xmlns="http://mydoc.example.org/schemas/"&gt;
1359 &lt;elem1&gt;...&lt;/elem1&gt;
1360 &lt;elem2&gt;...&lt;/elem2&gt;
1361&lt;/mydoc&gt;</pre>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +00001362
Daniel Veillardec70e912001-02-26 20:10:45 +00001363<p>The namespace value has to be an absolute URL, but the URL doesn't have to
1364point to any existing resource on the Web. It will bind all the element and
1365atributes with that URL. I suggest to use an URL within a domain you control,
1366and that the URL should contain some kind of version information if possible.
1367For example, <code>"http://www.gnome.org/gnumeric/1.0/"</code> is a good
1368namespace scheme.</p>
Daniel Veillardec303412000-03-24 13:41:54 +00001369
1370<p>Then when you load a file, make sure that a namespace carrying the
Daniel Veillard88f00ae2000-03-02 00:15:55 +00001371version-independent prefix is installed on the root element of your document,
Daniel Veillardc8eab3a1999-09-04 18:27:23 +00001372and if the version information don't match something you know, warn the user
1373and be liberal in what you accept as the input. Also do *not* try to base
Daniel Veillard60979bd2000-07-10 12:17:33 +00001374namespace checking on the prefix value. &lt;foo:text&gt; may be exactly the
Daniel Veillard91e9d582001-02-26 07:31:12 +00001375same as &lt;bar:text&gt; in another document. What really matters is the URI
Daniel Veillard60979bd2000-07-10 12:17:33 +00001376associated with the element or the attribute, not the prefix string (which is
Daniel Veillard91e9d582001-02-26 07:31:12 +00001377just a shortcut for the full URI). In libxml, element and attributes have an
Daniel Veillardec303412000-03-24 13:41:54 +00001378<code>ns</code> field pointing to an xmlNs structure detailing the namespace
Daniel Veillard91e9d582001-02-26 07:31:12 +00001379prefix and its URI.</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +00001380
1381<p>@@Interfaces@@</p>
1382
1383<p>@@Examples@@</p>
1384
Daniel Veillard91e9d582001-02-26 07:31:12 +00001385<p>Usually people object to using namespaces together with validity checking.
1386I will try to make sure that using namespaces won't break validity checking,
1387so even if you plan to use or currently are using validation I strongly
Daniel Veillardf13e1ed2000-03-06 07:41:49 +00001388suggest adding namespaces to your document. A default namespace scheme
Daniel Veillardc8eab3a1999-09-04 18:27:23 +00001389<code>xmlns="http://...."</code> should not break validity even on less
Daniel Veillard91e9d582001-02-26 07:31:12 +00001390flexible parsers. Using namespaces to mix and differentiate content coming
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +00001391from multiple DTDs will certainly break current validation schemes. I will
1392try to provide ways to do this, but this may not be portable or
1393standardized.</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +00001394
Daniel Veillard2f4dfc41999-09-24 14:03:48 +00001395<h2><a name="Validation">Validation, or are you afraid of DTDs ?</a></h2>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +00001396
1397<p>Well what is validation and what is a DTD ?</p>
1398
1399<p>Validation is the process of checking a document against a set of
Daniel Veillard91e9d582001-02-26 07:31:12 +00001400construction rules; a <strong>DTD</strong> (Document Type Definition) is such
Daniel Veillardc8eab3a1999-09-04 18:27:23 +00001401a set of rules.</p>
1402
1403<p>The validation process and building DTDs are the two most difficult parts
Daniel Veillard91e9d582001-02-26 07:31:12 +00001404of the XML life cycle. Briefly a DTD defines all the possibles element to be
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +00001405found within your document, what is the formal shape of your document tree
1406(by defining the allowed content of an element, either text, a regular
1407expression for the allowed list of children, or mixed content i.e. both text
1408and children). The DTD also defines the allowed attributes for all elements
1409and the types of the attributes. For more detailed information, I suggest
1410that you read the related parts of the XML specification, the examples found
1411under gnome-xml/test/valid/dtd and any of the large number of books available
1412on XML. The dia example in gnome-xml/test/valid should be both simple and
Daniel Veillardec70e912001-02-26 20:10:45 +00001413complete enough to allow you to build your own.</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +00001414
Daniel Veillard91e9d582001-02-26 07:31:12 +00001415<p>A word of warning, building a good DTD which will fit the needs of your
1416application in the long-term is far from trivial; however, the extra level of
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +00001417quality it can ensure is well worth the price for some sets of applications
1418or if you already have already a DTD defined for your application field.</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +00001419
1420<p>The validation is not completely finished but in a (very IMHO) usable
1421state. Until a real validation interface is defined the way to do it is to
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +00001422define and set the <strong>xmlDoValidityCheckingDefaultValue</strong>
1423external variable to 1, this will of course be changed at some point:</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +00001424
1425<p>extern int xmlDoValidityCheckingDefaultValue;</p>
1426
1427<p>...</p>
1428
1429<p>xmlDoValidityCheckingDefaultValue = 1;</p>
1430
1431<p></p>
1432
1433<p>To handle external entities, use the function
1434<strong>xmlSetExternalEntityLoader</strong>(xmlExternalEntityLoader f); to
1435link in you HTTP/FTP/Entities database library to the standard libxml
1436core.</p>
1437
1438<p>@@interfaces@@</p>
1439
Daniel Veillard35008381999-10-25 13:15:52 +00001440<h2><a name="DOM"></a><a name="Principles">DOM Principles</a></h2>
Daniel Veillardb05deb71999-08-10 19:04:08 +00001441
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +00001442<p><a href="http://www.w3.org/DOM/">DOM</a> stands for the <em>Document
1443Object Model</em>; this is an API for accessing XML or HTML structured
1444documents. Native support for DOM in Gnome is on the way (module gnome-dom),
1445and will be based on gnome-xml. This will be a far cleaner interface to
1446manipulate XML files within Gnome since it won't expose the internal
1447structure.</p>
Daniel Veillard14fff061999-06-22 21:49:07 +00001448
Daniel Veillardc8eab3a1999-09-04 18:27:23 +00001449<p>The current DOM implementation on top of libxml is the <a
Daniel Veillarda47fb3d2001-03-25 17:23:49 +00001450href="http://cvs.gnome.org/lxr/source/gdome2/">gdome2 Gnome module</a>, this
1451is a full DOM interface, thanks to Paolo Casarini, check the <a
1452href="http://www.cs.unibo.it/~casarini/gdome2/">Gdome2 homepage</a> for more
1453informations.</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +00001454
Daniel Veillard35008381999-10-25 13:15:52 +00001455<h2><a name="Example"></a><a name="real">A real example</a></h2>
Daniel Veillardb05deb71999-08-10 19:04:08 +00001456
1457<p>Here is a real size example, where the actual content of the application
1458data is not kept in the DOM tree but uses internal structures. It is based on
Daniel Veillard14fff061999-06-22 21:49:07 +00001459a proposal to keep a database of jobs related to Gnome, with an XML based
Daniel Veillardb05deb71999-08-10 19:04:08 +00001460storage structure. Here is an <a href="gjobs.xml">XML encoded jobs
1461base</a>:</p>
Daniel Veillard60979bd2000-07-10 12:17:33 +00001462<pre>&lt;?xml version="1.0"?&gt;
1463&lt;gjob:Helping xmlns:gjob="http://www.gnome.org/some-location"&gt;
1464 &lt;gjob:Jobs&gt;
Daniel Veillard14fff061999-06-22 21:49:07 +00001465
Daniel Veillard60979bd2000-07-10 12:17:33 +00001466 &lt;gjob:Job&gt;
1467 &lt;gjob:Project ID="3"/&gt;
1468 &lt;gjob:Application&gt;GBackup&lt;/gjob:Application&gt;
1469 &lt;gjob:Category&gt;Development&lt;/gjob:Category&gt;
Daniel Veillard14fff061999-06-22 21:49:07 +00001470
Daniel Veillard60979bd2000-07-10 12:17:33 +00001471 &lt;gjob:Update&gt;
1472 &lt;gjob:Status&gt;Open&lt;/gjob:Status&gt;
1473 &lt;gjob:Modified&gt;Mon, 07 Jun 1999 20:27:45 -0400 MET DST&lt;/gjob:Modified&gt;
1474 &lt;gjob:Salary&gt;USD 0.00&lt;/gjob:Salary&gt;
1475 &lt;/gjob:Update&gt;
Daniel Veillard14fff061999-06-22 21:49:07 +00001476
Daniel Veillard60979bd2000-07-10 12:17:33 +00001477 &lt;gjob:Developers&gt;
1478 &lt;gjob:Developer&gt;
1479 &lt;/gjob:Developer&gt;
1480 &lt;/gjob:Developers&gt;
Daniel Veillard14fff061999-06-22 21:49:07 +00001481
Daniel Veillard60979bd2000-07-10 12:17:33 +00001482 &lt;gjob:Contact&gt;
1483 &lt;gjob:Person&gt;Nathan Clemons&lt;/gjob:Person&gt;
1484 &lt;gjob:Email&gt;nathan@windsofstorm.net&lt;/gjob:Email&gt;
1485 &lt;gjob:Company&gt;
1486 &lt;/gjob:Company&gt;
1487 &lt;gjob:Organisation&gt;
1488 &lt;/gjob:Organisation&gt;
1489 &lt;gjob:Webpage&gt;
1490 &lt;/gjob:Webpage&gt;
1491 &lt;gjob:Snailmail&gt;
1492 &lt;/gjob:Snailmail&gt;
1493 &lt;gjob:Phone&gt;
1494 &lt;/gjob:Phone&gt;
1495 &lt;/gjob:Contact&gt;
Daniel Veillard14fff061999-06-22 21:49:07 +00001496
Daniel Veillard60979bd2000-07-10 12:17:33 +00001497 &lt;gjob:Requirements&gt;
Daniel Veillard14fff061999-06-22 21:49:07 +00001498 The program should be released as free software, under the GPL.
Daniel Veillard60979bd2000-07-10 12:17:33 +00001499 &lt;/gjob:Requirements&gt;
Daniel Veillard14fff061999-06-22 21:49:07 +00001500
Daniel Veillard60979bd2000-07-10 12:17:33 +00001501 &lt;gjob:Skills&gt;
1502 &lt;/gjob:Skills&gt;
Daniel Veillard14fff061999-06-22 21:49:07 +00001503
Daniel Veillard60979bd2000-07-10 12:17:33 +00001504 &lt;gjob:Details&gt;
Daniel Veillard14fff061999-06-22 21:49:07 +00001505 A GNOME based system that will allow a superuser to configure
1506 compressed and uncompressed files and/or file systems to be backed
1507 up with a supported media in the system. This should be able to
1508 perform via find commands generating a list of files that are passed
1509 to tar, dd, cpio, cp, gzip, etc., to be directed to the tape machine
1510 or via operations performed on the filesystem itself. Email
1511 notification and GUI status display very important.
Daniel Veillard60979bd2000-07-10 12:17:33 +00001512 &lt;/gjob:Details&gt;
Daniel Veillard14fff061999-06-22 21:49:07 +00001513
Daniel Veillard60979bd2000-07-10 12:17:33 +00001514 &lt;/gjob:Job&gt;
Daniel Veillard14fff061999-06-22 21:49:07 +00001515
Daniel Veillard60979bd2000-07-10 12:17:33 +00001516 &lt;/gjob:Jobs&gt;
1517&lt;/gjob:Helping&gt;</pre>
Daniel Veillardb05deb71999-08-10 19:04:08 +00001518
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +00001519<p>While loading the XML file into an internal DOM tree is a matter of
1520calling only a couple of functions, browsing the tree to gather the ata and
1521generate the internal structures is harder, and more error prone.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +00001522
1523<p>The suggested principle is to be tolerant with respect to the input
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +00001524structure. For example, the ordering of the attributes is not significant,
1525the XML specification is clear about it. It's also usually a good idea not to
Daniel Veillardec70e912001-02-26 20:10:45 +00001526depend on the order of the children of a given node, unless it really makes
1527things harder. Here is some code to parse the information for a person:</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +00001528<pre>/*
Daniel Veillard14fff061999-06-22 21:49:07 +00001529 * A person record
1530 */
1531typedef struct person {
1532 char *name;
1533 char *email;
1534 char *company;
1535 char *organisation;
1536 char *smail;
1537 char *webPage;
1538 char *phone;
1539} person, *personPtr;
1540
1541/*
1542 * And the code needed to parse it
1543 */
1544personPtr parsePerson(xmlDocPtr doc, xmlNsPtr ns, xmlNodePtr cur) {
1545 personPtr ret = NULL;
1546
1547DEBUG("parsePerson\n");
1548 /*
1549 * allocate the struct
1550 */
1551 ret = (personPtr) malloc(sizeof(person));
1552 if (ret == NULL) {
1553 fprintf(stderr,"out of memory\n");
Daniel Veillardb05deb71999-08-10 19:04:08 +00001554 return(NULL);
Daniel Veillard14fff061999-06-22 21:49:07 +00001555 }
1556 memset(ret, 0, sizeof(person));
1557
1558 /* We don't care what the top level element name is */
Daniel Veillard60979bd2000-07-10 12:17:33 +00001559 cur = cur-&gt;xmlChildrenNode;
Daniel Veillard14fff061999-06-22 21:49:07 +00001560 while (cur != NULL) {
Daniel Veillard60979bd2000-07-10 12:17:33 +00001561 if ((!strcmp(cur-&gt;name, "Person")) &amp;&amp; (cur-&gt;ns == ns))
1562 ret-&gt;name = xmlNodeListGetString(doc, cur-&gt;xmlChildrenNode, 1);
1563 if ((!strcmp(cur-&gt;name, "Email")) &amp;&amp; (cur-&gt;ns == ns))
1564 ret-&gt;email = xmlNodeListGetString(doc, cur-&gt;xmlChildrenNode, 1);
1565 cur = cur-&gt;next;
Daniel Veillard14fff061999-06-22 21:49:07 +00001566 }
1567
1568 return(ret);
Daniel Veillardb05deb71999-08-10 19:04:08 +00001569}</pre>
1570
Daniel Veillard91e9d582001-02-26 07:31:12 +00001571<p>Here are a couple of things to notice:</p>
Daniel Veillard14fff061999-06-22 21:49:07 +00001572<ul>
Daniel Veillard91e9d582001-02-26 07:31:12 +00001573 <li>Usually a recursive parsing style is the more convenient one: XML data
1574 is by nature subject to repetitive constructs and usually exibits highly
Daniel Veillardb05deb71999-08-10 19:04:08 +00001575 stuctured patterns.</li>
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +00001576 <li>The two arguments of type <em>xmlDocPtr</em> and <em>xmlNsPtr</em>,
1577 i.e. the pointer to the global XML document and the namespace reserved to
1578 the application. Document wide information are needed for example to
1579 decode entities and it's a good coding practice to define a namespace for
1580 your application set of data and test that the element and attributes
1581 you're analyzing actually pertains to your application space. This is
1582 done by a simple equality test (cur-&gt;ns == ns).</li>
Daniel Veillardec70e912001-02-26 20:10:45 +00001583 <li>To retrieve text and attributes value, you can use the function
1584 <em>xmlNodeListGetString</em> to gather all the text and entity reference
1585 nodes generated by the DOM output and produce an single text string.</li>
Daniel Veillard14fff061999-06-22 21:49:07 +00001586</ul>
Daniel Veillardb05deb71999-08-10 19:04:08 +00001587
1588<p>Here is another piece of code used to parse another level of the
1589structure:</p>
Daniel Veillard60979bd2000-07-10 12:17:33 +00001590<pre>#include &lt;libxml/tree.h&gt;
Daniel Veillard361d8452000-04-03 19:48:13 +00001591/*
Daniel Veillard14fff061999-06-22 21:49:07 +00001592 * a Description for a Job
1593 */
1594typedef struct job {
1595 char *projectID;
1596 char *application;
1597 char *category;
1598 personPtr contact;
1599 int nbDevelopers;
1600 personPtr developers[100]; /* using dynamic alloc is left as an exercise */
1601} job, *jobPtr;
1602
1603/*
1604 * And the code needed to parse it
1605 */
1606jobPtr parseJob(xmlDocPtr doc, xmlNsPtr ns, xmlNodePtr cur) {
1607 jobPtr ret = NULL;
1608
1609DEBUG("parseJob\n");
1610 /*
1611 * allocate the struct
1612 */
1613 ret = (jobPtr) malloc(sizeof(job));
1614 if (ret == NULL) {
1615 fprintf(stderr,"out of memory\n");
Daniel Veillardb05deb71999-08-10 19:04:08 +00001616 return(NULL);
Daniel Veillard14fff061999-06-22 21:49:07 +00001617 }
1618 memset(ret, 0, sizeof(job));
1619
1620 /* We don't care what the top level element name is */
Daniel Veillard60979bd2000-07-10 12:17:33 +00001621 cur = cur-&gt;xmlChildrenNode;
Daniel Veillard14fff061999-06-22 21:49:07 +00001622 while (cur != NULL) {
1623
Daniel Veillard60979bd2000-07-10 12:17:33 +00001624 if ((!strcmp(cur-&gt;name, "Project")) &amp;&amp; (cur-&gt;ns == ns)) {
1625 ret-&gt;projectID = xmlGetProp(cur, "ID");
1626 if (ret-&gt;projectID == NULL) {
Daniel Veillardb05deb71999-08-10 19:04:08 +00001627 fprintf(stderr, "Project has no ID\n");
1628 }
1629 }
Daniel Veillard60979bd2000-07-10 12:17:33 +00001630 if ((!strcmp(cur-&gt;name, "Application")) &amp;&amp; (cur-&gt;ns == ns))
1631 ret-&gt;application = xmlNodeListGetString(doc, cur-&gt;xmlChildrenNode, 1);
1632 if ((!strcmp(cur-&gt;name, "Category")) &amp;&amp; (cur-&gt;ns == ns))
1633 ret-&gt;category = xmlNodeListGetString(doc, cur-&gt;xmlChildrenNode, 1);
1634 if ((!strcmp(cur-&gt;name, "Contact")) &amp;&amp; (cur-&gt;ns == ns))
1635 ret-&gt;contact = parsePerson(doc, ns, cur);
1636 cur = cur-&gt;next;
Daniel Veillard14fff061999-06-22 21:49:07 +00001637 }
1638
1639 return(ret);
Daniel Veillardb05deb71999-08-10 19:04:08 +00001640}</pre>
Daniel Veillard14fff061999-06-22 21:49:07 +00001641
Daniel Veillardec70e912001-02-26 20:10:45 +00001642<p>Once you are used to it, writing this kind of code is quite simple, but
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +00001643boring. Ultimately, it could be possble to write stubbers taking either C
1644data structure definitions, a set of XML examples or an XML DTD and produce
1645the code needed to import and export the content between C data and XML
1646storage. This is left as an exercise to the reader :-)</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +00001647
Daniel Veillard6f0adb52000-07-03 11:41:26 +00001648<p>Feel free to use <a href="example/gjobread.c">the code for the full C
1649parsing example</a> as a template, it is also available with Makefile in the
1650Gnome CVS base under gnome-xml/example</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +00001651
Daniel Veillardc310d562000-06-23 18:32:15 +00001652<h2><a name="Contributi">Contributions</a></h2>
1653<ul>
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +00001654 <li><a href="mailto:ari@lusis.org">Ari Johnson</a>
1655 provides a C++ wrapper for libxml:
Daniel Veillardc310d562000-06-23 18:32:15 +00001656 <p>Website: <a
1657 href="http://lusis.org/~ari/xml++/">http://lusis.org/~ari/xml++/</a></p>
1658 <p>Download: <a
1659 href="http://lusis.org/~ari/xml++/libxml++.tar.gz">http://lusis.org/~ari/xml++/libxml++.tar.gz</a></p>
1660 </li>
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +00001661 <li><a href="mailto:izlatkovic@daenet.de">Igor Zlatkovic</a>
1662 is now the maintainer of the Windows port, <a
Daniel Veillard95189532001-07-26 18:30:26 +00001663 href="http://www.fh-frankfurt.de/~igor/projects/libxml/index.html">he
1664 provides binaries</a></li>
Daniel Veillarde356c282001-03-10 12:32:04 +00001665 <li><a
1666 href="http://mail.gnome.org/archives/xml/2001-March/msg00014.html">Matt
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +00001667 Sergeant</a>
1668 developped <a href="http://axkit.org/download/">XML::LibXSLT</a>, a perl
1669 wrapper for libxml2/libxslt as part of the <a
1670 href="http://axkit.com/">AxKit XML application server</a></li>
1671 <li><a href="mailto:fnatter@gmx.net">Felix Natter</a>
1672 and <a href="mailto:geertk@ai.rug.nl">Geert Kloosterman</a> provide <a
Daniel Veillardca989762001-06-23 17:39:29 +00001673 href="libxml-doc.el">an emacs module</a> to lookup libxml(2) functions
Daniel Veillard3f6f7f62000-06-30 17:58:25 +00001674 documentation</li>
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +00001675 <li><a href="mailto:sherwin@nlm.nih.gov">Ziying Sherwin</a>
1676 provided <a href="http://xmlsoft.org/messages/0488.html">man
1677 pages</a></li>
Daniel Veillard5168dbf2001-07-07 00:18:23 +00001678 <li>there is a module for <a
1679 href="http://acs-misc.sourceforge.net/nsxml.html">libxml/libxslt support
1680 in OpenNSD/AOLServer</a></li>
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +00001681 <li><a href="mailto:dkuhlman@cutter.rexx.com">Dave Kuhlman</a>
1682 provides libxml/libxslt <a href="http://www.rexx.com/~dkuhlman">wrappers
1683 for Python</a></li>
Daniel Veillardc310d562000-06-23 18:32:15 +00001684</ul>
1685
Daniel Veillardc8eab3a1999-09-04 18:27:23 +00001686<p></p>
1687
Daniel Veillardf7ed3362001-08-17 12:01:21 +00001688<p><a href="mailto:daniel@veillard.com">Daniel Veillard</a></p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +00001689
Daniel Veillard04382ae2001-09-12 18:51:30 +00001690<p>$Id: xml.html,v 1.108 2001/08/24 00:49:01 veillard Exp $</p>
Daniel Veillardccb09631998-10-27 06:21:04 +00001691</body>
1692</html>