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blob: 2eb16417bb87e6b2a05f8c818c16633f47b07673 [file] [log] [blame]
Daniel Veillard09ab7e12001-07-10 15:49:44 +0000[diff] [blame]1<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
2 "http://www.w3.org/TR/html4/loose.dtd">
Daniel Veillardccb09631998-10-27 06:21:04 +0000[diff] [blame]3<html>
4<head>
Daniel Veillardec78c0f2000-08-25 10:25:23 +0000[diff] [blame]5 <title>The XML C library for Gnome</title>
Daniel Veillard95189532001-07-26 18:30:26 +0000[diff] [blame]6 <meta name="GENERATOR" content="amaya V4.1">
Daniel Veillardb24054a1999-12-18 15:32:46 +0000[diff] [blame]7 <meta http-equiv="Content-Type" content="text/html">
Daniel Veillardccb09631998-10-27 06:21:04 +0000[diff] [blame]8</head>
Daniel Veillardccb09631998-10-27 06:21:04 +0000[diff] [blame]9
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]10<body bgcolor="#ffffff">
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]11<p><a href="http://www.gnome.org/"><img src="smallfootonly.gif"
12alt="Gnome Logo"></a><a href="http://www.w3.org/Status"><img src="w3c.png"
Daniel Veillardb370a742001-06-09 16:58:47 +0000[diff] [blame]13alt="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 +0000[diff] [blame]15
Daniel Veillardec78c0f2000-08-25 10:25:23 +0000[diff] [blame]16<h1 align="center">The XML C library for Gnome</h1>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]17
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]18<h2 style="text-align: center">libxml, a.k.a. gnome-xml</h2>
19
20<p></p>
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]21<ul>
22 <li><a href="#Introducti">Introduction</a></li>
23 <li><a href="#Documentat">Documentation</a></li>
Daniel Veillardd5f97f82000-09-17 16:38:14 +0000[diff] [blame]24 <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 +0000[diff] [blame]26 <li><a href="#Downloads">Downloads</a></li>
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]27 <li><a href="#News">News</a></li>
28 <li><a href="#XML">XML</a></li>
Daniel Veillard82687162001-01-22 15:32:01 +0000[diff] [blame]29 <li><a href="#XSLT">XSLT</a></li>
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]30 <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 +0000[diff] [blame]34 <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 +0000[diff] [blame]37 <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 +0000[diff] [blame]49 <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 +0000[diff] [blame]58 <li><a href="xmlmem.html">libxml Memory interfaces</a></li>
Daniel Veillard300f7d62000-11-24 13:04:04 +0000[diff] [blame]59 <li><a href="xmldtd.html">a short introduction about DTDs and
60 libxml</a></li>
Daniel Veillard6e6a6cc2001-02-15 15:55:44 +0000[diff] [blame]61 <li><a href="http://xmlsoft.org/XSLT/">the libxslt page</a></li>
Daniel Veillard7b06bcb2001-06-22 16:03:51 +0000[diff] [blame]62 <li><a href="http://www.cs.unibo.it/~casarini/gdome2/">the gdome2 page: a
63 standard DOM interface for libxml2</a></li>
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]64</ul>
65
66<h2><a name="Introducti">Introduction</a></h2>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]67
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]68<p>This document describes libxml, the <a
Daniel Veillardec78c0f2000-08-25 10:25:23 +0000[diff] [blame]69href="http://www.w3.org/XML/">XML</a> C library developped for the <a
70href="http://www.gnome.org/">Gnome</a> project. <a
71href="http://www.w3.org/XML/">XML is a standard</a> for building tag-based
72structured documents/data.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]73
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]74<p>Here are some key points about libxml:</p>
75<ul>
Daniel Veillard189446d2000-10-13 10:23:06 +0000[diff] [blame]76 <li>Libxml exports Push and Pull type parser interfaces for both XML and
77 HTML.</li>
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]78 <li>Libxml can do DTD validation at parse time, using a parsed document
79 instance, or with an arbitrary DTD.</li>
80 <li>Libxml now includes nearly complete <a
Daniel Veillard8c2ecaf2001-07-10 17:53:07 +0000[diff] [blame]81 href="http://www.w3.org/TR/xpath">XPath</a>, <a
82 href="http://www.w3.org/TR/xptr">XPointer</a> and <a
83 href="http://www.w3.org/TR/xinclude">XInclude</a> implementations.</li>
Daniel Veillardec78c0f2000-08-25 10:25:23 +0000[diff] [blame]84 <li>It is written in plain C, making as few assumptions as possible, and
Daniel Veillard189446d2000-10-13 10:23:06 +0000[diff] [blame]85 sticking closely to ANSI C/POSIX for easy embedding. Works on
Daniel Veillardab8500d2000-10-15 21:06:19 +0000[diff] [blame]86 Linux/Unix/Windows, ported to a number of other platforms.</li>
Daniel Veillardec70e912001-02-26 20:10:45 +0000[diff] [blame]87 <li>Basic support for HTTP and FTP client allowing aplications to fetch
88 remote resources</li>
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]89 <li>The design is modular, most of the extensions can be compiled out.</li>
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]90 <li>The internal document repesentation is as close as possible to the <a
91 href="http://www.w3.org/DOM/">DOM</a> interfaces.</li>
92 <li>Libxml also has a <a href="http://www.megginson.com/SAX/index.html">SAX
Daniel Veillard402e8c82000-02-29 22:57:47 +0000[diff] [blame]93 like interface</a>; the interface is designed to be compatible with <a
94 href="http://www.jclark.com/xml/expat.html">Expat</a>.</li>
Daniel Veillardec303412000-03-24 13:41:54 +0000[diff] [blame]95 <li>This library is released both under the <a
96 href="http://www.w3.org/Consortium/Legal/copyright-software-19980720.html">W3C
Daniel Veillard189446d2000-10-13 10:23:06 +0000[diff] [blame]97 IPR</a> and the <a href="http://www.gnu.org/copyleft/lesser.html">GNU
98 LGPL</a>. Use either at your convenience, basically this should make
99 everybody happy, if not, drop me a mail.</li>
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]100</ul>
Daniel Veillardccb09631998-10-27 06:21:04 +0000[diff] [blame]101
Daniel Veillarde0c1d722001-03-21 10:28:36 +0000[diff] [blame]102<p>Warning: unless you are forced to because your application links with a
103Gnome library requiring it, <strong><span
104style="background-color: #FF0000">Do Not Use libxml1</span></strong>, use
105libxml2</p>
106
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]107<h2><a name="Documentat">Documentation</a></h2>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]108
Daniel Veillard402e8c82000-02-29 22:57:47 +0000[diff] [blame]109<p>There are some on-line resources about using libxml:</p>
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]110<ol>
Daniel Veillard365e13b2000-07-02 07:56:37 +0000[diff] [blame]111 <li>Check the <a href="FAQ.html">FAQ</a></li>
Daniel Veillardc19fccc2000-07-03 11:52:01 +0000[diff] [blame]112 <li>Check the <a href="http://xmlsoft.org/html/libxml-lib.html">extensive
Daniel Veillard8c6d6af2000-08-25 17:14:13 +0000[diff] [blame]113 documentation</a> automatically extracted from code comments (using <a
114 href="http://cvs.gnome.org/bonsai/rview.cgi?cvsroot=/cvs/gnome&amp;dir=gtk-doc">gtk
115 doc</a>).</li>
Daniel Veillard8d869642000-07-14 12:12:59 +0000[diff] [blame]116 <li>Look at the documentation about <a href="encoding.html">libxml
117 internationalization support</a></li>
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]118 <li>This page provides a global overview and <a href="#real">some
Daniel Veillard402e8c82000-02-29 22:57:47 +0000[diff] [blame]119 examples</a> on how to use libxml.</li>
Daniel Veillard95189532001-07-26 18:30:26 +0000[diff] [blame]120 <li><a href="mailto:james@daa.com.au">James Henstridge</a> wrote <a
Daniel Veillard402e8c82000-02-29 22:57:47 +0000[diff] [blame]121 href="http://www.daa.com.au/~james/gnome/xml-sax/xml-sax.html">some nice
122 documentation</a> explaining how to use the libxml SAX interface.</li>
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]123 <li>George Lebl wrote <a
124 href="http://www-4.ibm.com/software/developer/library/gnome3/">an article
Daniel Veillard402e8c82000-02-29 22:57:47 +0000[diff] [blame]125 for IBM developerWorks</a> about using libxml.</li>
Daniel Veillardec303412000-03-24 13:41:54 +0000[diff] [blame]126 <li>Check <a href="http://cvs.gnome.org/lxr/source/gnome-xml/TODO">the TODO
127 file</a></li>
128 <li>Read the <a href="upgrade.html">1.x to 2.x upgrade path</a>. If you are
129 starting a new project using libxml you should really use the 2.x
130 version.</li>
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]131 <li>And don't forget to look at the <a href="/messages/">mailing-list
Daniel Veillardc310d562000-06-23 18:32:15 +0000[diff] [blame]132 archive</a>.</li>
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]133</ol>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]134
Daniel Veillardd5f97f82000-09-17 16:38:14 +0000[diff] [blame]135<h2><a name="Reporting">Reporting bugs and getting help</a></h2>
Daniel Veillard4c3a2031999-11-19 17:46:26 +0000[diff] [blame]136
Daniel Veillard95189532001-07-26 18:30:26 +0000[diff] [blame]137<p>Well, bugs or missing features are always possible, and I will make a point
138of fixing them in a timely fashion. The best way to report a bug is to use the
139<a href="http://bugzilla.gnome.org/buglist.cgi?product=libxml">Gnome bug
140tracking database</a> (make sure to use the "libxml" module name). I look at
141reports there regularly and it's good to have a reminder when a bug is still
142open. Check the <a
143href="http://bugzilla.gnome.org/bugwritinghelp.html">instructions on reporting
144bugs</a> and be sure to specify that the bug is for the package libxml.</p>
Daniel Veillard4c3a2031999-11-19 17:46:26 +0000[diff] [blame]145
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]146<p>There is also a mailing-list <a
Daniel Veillard3197f162001-04-04 00:40:08 +0000[diff] [blame]147href="mailto:xml@gnome.org">xml@gnome.org</a> for libxml, with an <a
148href="http://mail.gnome.org/archives/xml/">on-line archive</a> (<a
Daniel Veillard95189532001-07-26 18:30:26 +0000[diff] [blame]149href="http://xmlsoft.org/messages">old</a>). To subscribe to this list, please
150visit the <a href="http://mail.gnome.org/mailman/listinfo/xml">associated
151Web</a> page and follow the instructions. <strong>Do not send code, I won't
152debug it</strong> (but patches are really appreciated!).</p>
Daniel Veillard234547b2001-07-05 09:46:10 +0000[diff] [blame]153
154<p>Check the following too before posting:</p>
155<ul>
156 <li>make sure you are <a href="ftp://xmlsoft.org/">using a recent
157 version</a>, and that the problem still shows up in those</li>
158 <li>check the <a href="http://mail.gnome.org/archives/xml/">list
159 archives</a> to see if the problem was reported already, in this case
Daniel Veillard95189532001-07-26 18:30:26 +0000[diff] [blame]160 there is probably a fix available, similary check the <a href="http://bugzilla.gnome.org/buglist.cgi?product=libxml&amp;product=libxslt&amp;bug_status=UNCONFIRMED&amp;bug_status=NEW&amp;bug_status=ASSIGNED&amp;bug_status=NEEDINFO&amp;bug_status=REOPENED&amp;bug_status=RESOLVED&amp;bug_status=VERIFIED&amp;email1=&amp;emailtype1=substring&amp;emailassigned_to1=1&amp;emailreporter1=1&amp;emailcc1=1&amp;emaillongdesc1=1&amp;email2=&amp;emailtype2=substring&amp;emailassigned_to2=1&amp;emailreporter2=1&amp;emailcc2=1&amp;emaillongdesc2=1&amp;changedin=&amp;chfieldfrom=&amp;chfieldto=Now&amp;chfieldvalue=&amp;short_desc=&amp;short_desc_type=substring&amp;long_desc=&amp;long_desc_type=substring&amp;bug_file_loc=&amp;bug_file_loc_type=substring&amp;status_whiteboard=&amp;status_whiteboard_type=substring&amp;keywords=&amp;keywords_type=anywords&amp;op_sys_details=&amp;op_sys_details_type=substring&amp;version_details=&amp;version_details_type=substring&amp;cmdtype=doit&amp;newqueryname=&amp;order=Reuse+same+sort+as+last+time&amp;form_name=query">registered open
161 bugs</a></li>
Daniel Veillard234547b2001-07-05 09:46:10 +0000[diff] [blame]162 <li>make sure you can reproduce the bug with xmllint or one of the test
163 programs found in source in the distribution</li>
164 <li>Please send the command showing the error as well as the input (as an
165 attachement)</li>
166</ul>
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]167
Daniel Veillard402e8c82000-02-29 22:57:47 +0000[diff] [blame]168<p>Alternatively, you can just send the bug to the <a
Daniel Veillard33a67802001-03-07 09:44:02 +0000[diff] [blame]169href="mailto:xml@gnome.org">xml@gnome.org</a> list; if it's really libxml
Daniel Veillard95189532001-07-26 18:30:26 +0000[diff] [blame]170related I will approve it.. Please do not send me mail directly especially for
171portability problem, it makes things really harder to track and in some cases
172I'm not the best person to answer a given question, ask the list instead.</p>
Daniel Veillard4c3a2031999-11-19 17:46:26 +0000[diff] [blame]173
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]174<p>Of course, bugs reported with a suggested patch for fixing them will
Daniel Veillardec303412000-03-24 13:41:54 +0000[diff] [blame]175probably be processed faster.</p>
176
177<p>If you're looking for help, a quick look at <a
178href="http://xmlsoft.org/messages/#407">the list archive</a> may actually
179provide the answer, I usually send source samples when answering libxml usage
Daniel Veillard6f0adb52000-07-03 11:41:26 +0000[diff] [blame]180questions. The <a href="http://xmlsoft.org/html/book1.html">auto-generated
Daniel Veillardec303412000-03-24 13:41:54 +0000[diff] [blame]181documentantion</a> is not as polished as I would like (i need to learn more
182about Docbook), but it's a good starting point.</p>
183
Daniel Veillardd5f97f82000-09-17 16:38:14 +0000[diff] [blame]184<h2><a name="help">How to help</a></h2>
185
186<p>You can help the project in various ways, the best thing to do first is to
187subscribe to the mailing-list as explained before, check the <a
188href="http://xmlsoft.org/messages/">archives </a>and the <a
189href="http://bugs.gnome.org/db/pa/lgnome-xml.html">Gnome bug
190database:</a>:</p>
191<ol>
192 <li>provide patches when you find problems</li>
Daniel Veillard189446d2000-10-13 10:23:06 +0000[diff] [blame]193 <li>provide the diffs when you port libxml to a new platform. They may not
Daniel Veillardab8500d2000-10-15 21:06:19 +0000[diff] [blame]194 be integrated in all cases but help pinpointing portability problems
195 and</li>
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]196 <li>provide documentation fixes (either as patches to the code comments or
Daniel Veillardd5f97f82000-09-17 16:38:14 +0000[diff] [blame]197 as HTML diffs).</li>
198 <li>provide new documentations pieces (translations, examples, etc ...)</li>
199 <li>Check the TODO file and try to close one of the items</li>
200 <li>take one of the points raised in the archive or the bug database and
Daniel Veillard33a67802001-03-07 09:44:02 +0000[diff] [blame]201 provide a fix. <a href="mailto:Daniel.Veillard@imag.fr">Get in touch with
Daniel Veillardd5f97f82000-09-17 16:38:14 +0000[diff] [blame]202 me </a>before to avoid synchronization problems and check that the
203 suggested fix will fit in nicely :-)</li>
204</ol>
205
Daniel Veillard10a2c651999-12-12 13:03:50 +0000[diff] [blame]206<h2><a name="Downloads">Downloads</a></h2>
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]207
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]208<p>The latest versions of libxml can be found on <a
Daniel Veillard20c8cf22001-06-26 22:47:36 +0000[diff] [blame]209href="ftp://xmlsoft.org/">xmlsoft.org</a> (<a
210href="ftp://speakeasy.rpmfind.net/pub/libxml/">Seattle</a>, <a
211href="ftp://fr.rpmfind.net/pub/libxml/">France</a>) or on the <a
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]212href="ftp://ftp.gnome.org/pub/GNOME/MIRRORS.html">Gnome FTP server</a> either
Daniel Veillard10a2c651999-12-12 13:03:50 +0000[diff] [blame]213as a <a href="ftp://ftp.gnome.org/pub/GNOME/stable/sources/libxml/">source
Daniel Veillard306be992000-07-03 12:38:45 +0000[diff] [blame]214archive</a> or <a
Daniel Veillarda41123c2001-04-22 19:31:20 +0000[diff] [blame]215href="ftp://ftp.gnome.org/pub/GNOME/stable/redhat/i386/libxml/">RPM
216packages</a>. (NOTE that you need both the <a
Daniel Veillardc19fccc2000-07-03 11:52:01 +0000[diff] [blame]217href="http://rpmfind.net/linux/RPM/libxml2.html">libxml(2)</a> and <a
218href="http://rpmfind.net/linux/RPM/libxml2-devel.html">libxml(2)-devel</a>
Daniel Veillard95189532001-07-26 18:30:26 +0000[diff] [blame]219packages installed to compile applications using libxml.) <a
220href="mailto:izlatkovic@daenet.de">Igor Zlatkovic</a> is now the maintainer
221of the Windows port, <a
222href="http://www.fh-frankfurt.de/~igor/projects/libxml/index.html">he provides
223binaries</a></p>
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]224
Daniel Veillard6c8b1172000-03-01 00:40:41 +0000[diff] [blame]225<p><a name="Snapshot">Snapshot:</a></p>
226<ul>
227 <li>Code from the W3C cvs base libxml <a
Daniel Veillard33a67802001-03-07 09:44:02 +0000[diff] [blame]228 href="ftp://xmlsoft.org/cvs-snapshot.tar.gz">cvs-snapshot.tar.gz</a></li>
Daniel Veillard6c8b1172000-03-01 00:40:41 +0000[diff] [blame]229 <li>Docs, content of the web site, the list archive included <a
Daniel Veillard33a67802001-03-07 09:44:02 +0000[diff] [blame]230 href="ftp://xmlsoft.org/libxml-docs.tar.gz">libxml-docs.tar.gz</a></li>
Daniel Veillard6c8b1172000-03-01 00:40:41 +0000[diff] [blame]231</ul>
232
233<p><a name="Contribs">Contribs:</a></p>
234
235<p>I do accept external contributions, especially if compiling on another
236platform, get in touch with me to upload the package. I will keep them in the
Daniel Veillard33a67802001-03-07 09:44:02 +0000[diff] [blame]237<a href="ftp://xmlsoft.org/contribs/">contrib directory</a></p>
Daniel Veillard6c8b1172000-03-01 00:40:41 +0000[diff] [blame]238
Daniel Veillard82687162001-01-22 15:32:01 +0000[diff] [blame]239<p>Libxml is also available from CVS:</p>
Daniel Veillard10a2c651999-12-12 13:03:50 +0000[diff] [blame]240<ul>
Daniel Veillard10a2c651999-12-12 13:03:50 +0000[diff] [blame]241 <li><p>The <a
242 href="http://cvs.gnome.org/bonsai/rview.cgi?cvsroot=/cvs/gnome&amp;dir=gnome-xml">Gnome
Daniel Veillard402e8c82000-02-29 22:57:47 +0000[diff] [blame]243 CVS base</a>. Check the <a
Daniel Veillard95189532001-07-26 18:30:26 +0000[diff] [blame]244 href="http://developer.gnome.org/tools/cvs.html">Gnome CVS Tools</a> page;
245 the CVS module is <b>gnome-xml</b>.</p>
Daniel Veillard10a2c651999-12-12 13:03:50 +0000[diff] [blame]246 </li>
Daniel Veillard82687162001-01-22 15:32:01 +0000[diff] [blame]247 <li>The <strong>libxslt</strong> module is also present there</li>
Daniel Veillard10a2c651999-12-12 13:03:50 +0000[diff] [blame]248</ul>
249
250<h2><a name="News">News</a></h2>
251
Daniel Veillard944b5ff1999-12-15 19:08:24 +0000[diff] [blame]252<h3>CVS only : check the <a
253href="http://cvs.gnome.org/lxr/source/gnome-xml/ChangeLog">Changelog</a> file
Daniel Veillard189446d2000-10-13 10:23:06 +0000[diff] [blame]254for a really accurate description</h3>
Daniel Veillardab8500d2000-10-15 21:06:19 +0000[diff] [blame]255
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]256<p>Items floating around but not actively worked on, get in touch with me if
Daniel Veillardab8500d2000-10-15 21:06:19 +0000[diff] [blame]257you want to test those</p>
258<ul>
Daniel Veillard95189532001-07-26 18:30:26 +0000[diff] [blame]259 <li>Implementing <a href="http://xmlsoft.org/XSLT">XSLT</a>, this is done as
260 a separate C library on top of libxml called libxslt</li>
Daniel Veillard28929b22000-11-13 18:22:49 +0000[diff] [blame]261 <li>Finishing up <a href="http://www.w3.org/TR/xptr">XPointer</a> and <a
262 href="http://www.w3.org/TR/xinclude">XInclude</a></li>
Daniel Veillard95189532001-07-26 18:30:26 +0000[diff] [blame]263 <li>(seeems working but delayed from release) parsing/import of Docbook SGML
264 docs</li>
Daniel Veillard09ab7e12001-07-10 15:49:44 +0000[diff] [blame]265</ul>
266
267<h3>2.4.0: July 10 2001</h3>
268<ul>
269 <li>Fixed a few bugs in XPath, validation, and tree handling.</li>
270 <li>Fixed XML Base implementation, added a coupel of examples to the
271 regression tests</li>
272 <li>A bit of cleanup</li>
Daniel Veillardab8500d2000-10-15 21:06:19 +0000[diff] [blame]273</ul>
274
Daniel Veillard5b43fde2001-07-05 23:31:40 +0000[diff] [blame]275<h3>2.3.14: July 5 2001</h3>
276<ul>
Daniel Veillard95189532001-07-26 18:30:26 +0000[diff] [blame]277 <li>fixed some entities problems and reduce mem requirement when substituing
278 them</li>
Daniel Veillard5b43fde2001-07-05 23:31:40 +0000[diff] [blame]279 <li>lots of improvements in the XPath queries interpreter can be
280 substancially faster</li>
281 <li>Makefiles and configure cleanups</li>
282 <li>Fixes to XPath variable eval, and compare on empty node set</li>
283 <li>HTML tag closing bug fixed</li>
284 <li>Fixed an URI reference computating problem when validating</li>
285</ul>
286
Daniel Veillard2adbb512001-06-28 16:20:36 +0000[diff] [blame]287<h3>2.3.13: June 28 2001</h3>
288<ul>
289 <li>2.3.12 configure.in was broken as well as the push mode XML parser</li>
290 <li>a few more fixes for compilation on Windows MSC by Yon Derek</li>
291</ul>
292
293<h3>1.8.14: June 28 2001</h3>
294<ul>
295 <li>Zbigniew Chyla gave a patch to use the old XML parser in push mode</li>
296 <li>Small Makefile fix</li>
297</ul>
298
Daniel Veillard11648102001-06-26 16:08:24 +0000[diff] [blame]299<h3>2.3.12: June 26 2001</h3>
300<ul>
301 <li>lots of cleanup</li>
302 <li>a couple of validation fix</li>
303 <li>fixed line number counting</li>
304 <li>fixed serious problems in the XInclude processing</li>
305 <li>added support for UTF8 BOM at beginning of entities</li>
306 <li>fixed a strange gcc optimizer bugs in xpath handling of float, gcc-3.0
307 miscompile uri.c (William), Thomas Leitner provided a fix for the
308 optimizer on Tru64</li>
309 <li>incorporated Yon Derek and Igor Zlatkovic fixes and improvements for
310 compilation on Windows MSC</li>
311 <li>update of libxml-doc.el (Felix Natter)</li>
312 <li>fixed 2 bugs in URI normalization code</li>
313</ul>
314
Daniel Veillarde3c81b52001-06-17 14:50:34 +0000[diff] [blame]315<h3>2.3.11: June 17 2001</h3>
316<ul>
317 <li>updates to trio, Makefiles and configure should fix some portability
318 problems (alpha)</li>
319 <li>fixed some HTML serialization problems (pre, script, and block/inline
320 handling), added encoding aware APIs, cleanup of this code</li>
321 <li>added xmlHasNsProp()</li>
322 <li>implemented a specific PI for encoding support in the DocBook SGML
323 parser</li>
324 <li>some XPath fixes (-Infinity, / as a function parameter and namespaces
325 node selection)</li>
326 <li>fixed a performance problem and an error in the validation code</li>
327 <li>fixed XInclude routine to implement the recursive behaviour</li>
328 <li>fixed xmlFreeNode problem when libxml is included statically twice</li>
329 <li>added --version to xmllint for bug reports</li>
330</ul>
331
Daniel Veillard2e4f1882001-06-01 10:11:57 +0000[diff] [blame]332<h3>2.3.10: June 1 2001</h3>
333<ul>
334 <li>fixed the SGML catalog support</li>
Daniel Veillard95189532001-07-26 18:30:26 +0000[diff] [blame]335 <li>a number of reported bugs got fixed, in XPath, iconv detection, XInclude
336 processing</li>
Daniel Veillard2e4f1882001-06-01 10:11:57 +0000[diff] [blame]337 <li>XPath string function should now handle unicode correctly</li>
338</ul>
339
Daniel Veillard4623acd2001-05-19 15:13:15 +0000[diff] [blame]340<h3>2.3.9: May 19 2001</h3>
341
342<p>Lots of bugfixes, and added a basic SGML catalog support:</p>
343<ul>
344 <li>HTML push bugfix #54891 and another patch from Jonas Borgström</li>
345 <li>some serious speed optimisation again</li>
346 <li>some documentation cleanups</li>
347 <li>trying to get better linking on solaris (-R)</li>
348 <li>XPath API cleanup from Thomas Broyer</li>
349 <li>Validation bug fixed #54631, added a patch from Gary Pennington, fixed
350 xmlValidGetValidElements()</li>
351 <li>Added an INSTALL file</li>
352 <li>Attribute removal added to API: #54433</li>
353 <li>added a basic support for SGML catalogs</li>
354 <li>fixed xmlKeepBlanksDefault(0) API</li>
355 <li>bugfix in xmlNodeGetLang()</li>
356 <li>fixed a small configure portability problem</li>
357 <li>fixed an inversion of SYSTEM and PUBLIC identifier in HTML document</li>
358</ul>
359
Daniel Veillarda265af72001-05-14 11:13:58 +0000[diff] [blame]360<h3>1.8.13: May 14 2001</h3>
361<ul>
362 <li>bugfixes release of the old libxml1 branch used by Gnome</li>
363</ul>
364
Daniel Veillard3bbbe6f2001-05-03 11:15:37 +0000[diff] [blame]365<h3>2.3.8: May 3 2001</h3>
366<ul>
367 <li>Integrated an SGML DocBook parser for the Gnome project</li>
368 <li>Fixed a few things in the HTML parser</li>
369 <li>Fixed some XPath bugs raised by XSLT use, tried to fix the floating
370 point portability issue</li>
Daniel Veillard95189532001-07-26 18:30:26 +0000[diff] [blame]371 <li>Speed improvement (8M/s for SAX, 3M/s for DOM, 1.5M/s for DOM+validation
372 using the XML REC as input and a 700MHz celeron).</li>
Daniel Veillard3bbbe6f2001-05-03 11:15:37 +0000[diff] [blame]373 <li>incorporated more Windows cleanup</li>
374 <li>added xmlSaveFormatFile()</li>
375 <li>fixed problems in copying nodes with entities references (gdome)</li>
376 <li>removed some troubles surrounding the new validation module</li>
377</ul>
378
Daniel Veillarda41123c2001-04-22 19:31:20 +0000[diff] [blame]379<h3>2.3.7: April 22 2001</h3>
380<ul>
381 <li>lots of small bug fixes, corrected XPointer</li>
382 <li>Non determinist content model validation support</li>
383 <li>added xmlDocCopyNode for gdome2</li>
384 <li>revamped the way the HTML parser handles end of tags</li>
385 <li>XPath: corrctions of namespacessupport and number formatting</li>
386 <li>Windows: Igor Zlatkovic patches for MSC compilation</li>
387 <li>HTML ouput fixes from P C Chow and William M. Brack</li>
388 <li>Improved validation speed sensible for DocBook</li>
389 <li>fixed a big bug with ID declared in external parsed entities</li>
390 <li>portability fixes, update of Trio from Bjorn Reese</li>
391</ul>
392
Daniel Veillardafc73112001-04-11 11:51:41 +0000[diff] [blame]393<h3>2.3.6: April 8 2001</h3>
394<ul>
395 <li>Code cleanup using extreme gcc compiler warning options, found and
396 cleared half a dozen potential problem</li>
397 <li>the Eazel team found an XML parser bug</li>
398 <li>cleaned up the user of some of the string formatting function. used the
399 trio library code to provide the one needed when the platform is missing
400 them</li>
Daniel Veillard95189532001-07-26 18:30:26 +0000[diff] [blame]401 <li>xpath: removed a memory leak and fixed the predicate evaluation problem,
402 extended the testsuite and cleaned up the result. XPointer seems broken
403 ...</li>
Daniel Veillardafc73112001-04-11 11:51:41 +0000[diff] [blame]404</ul>
405
Daniel Veillard56a4cb82001-03-24 17:00:36 +0000[diff] [blame]406<h3>2.3.5: Mar 23 2001</h3>
407<ul>
408 <li>Biggest change is separate parsing and evaluation of XPath expressions,
409 there is some new APIs for this too</li>
410 <li>included a number of bug fixes(XML push parser, 51876, notations,
411 52299)</li>
412 <li>Fixed some portability issues</li>
413</ul>
414
Daniel Veillarde356c282001-03-10 12:32:04 +0000[diff] [blame]415<h3>2.3.4: Mar 10 2001</h3>
416<ul>
417 <li>Fixed bugs #51860 and #51861</li>
418 <li>Added a global variable xmlDefaultBufferSize to allow default buffer
419 size to be application tunable.</li>
420 <li>Some cleanup in the validation code, still a bug left and this part
421 should probably be rewritten to support ambiguous content model :-\</li>
422 <li>Fix a couple of serious bugs introduced or raised by changes in 2.3.3
423 parser</li>
424 <li>Fixed another bug in xmlNodeGetContent()</li>
425 <li>Bjorn fixed XPath node collection and Number formatting</li>
426 <li>Fixed a loop reported in the HTML parsing</li>
427 <li>blank space are reported even if the Dtd content model proves that they
428 are formatting spaces, this is for XmL conformance</li>
429</ul>
430
Daniel Veillardb402c072001-03-01 17:28:58 +0000[diff] [blame]431<h3>2.3.3: Mar 1 2001</h3>
432<ul>
433 <li>small change in XPath for XSLT</li>
434 <li>documentation cleanups</li>
435 <li>fix in validation by Gary Pennington</li>
436 <li>serious parsing performances improvements</li>
437</ul>
438
Daniel Veillardec70e912001-02-26 20:10:45 +0000[diff] [blame]439<h3>2.3.2: Feb 24 2001</h3>
Daniel Veillard71681102001-02-24 17:48:53 +0000[diff] [blame]440<ul>
441 <li>chasing XPath bugs, found a bunch, completed some TODO</li>
442 <li>fixed a Dtd parsing bug</li>
443 <li>fixed a bug in xmlNodeGetContent</li>
444 <li>ID/IDREF support partly rewritten by Gary Pennington</li>
445</ul>
446
Daniel Veillardec70e912001-02-26 20:10:45 +0000[diff] [blame]447<h3>2.3.1: Feb 15 2001</h3>
Daniel Veillard6e6a6cc2001-02-15 15:55:44 +0000[diff] [blame]448<ul>
449 <li>some XPath and HTML bug fixes for XSLT</li>
450 <li>small extension of the hash table interfaces for DOM gdome2
451 implementation</li>
452 <li>A few bug fixes</li>
453</ul>
454
Daniel Veillardec70e912001-02-26 20:10:45 +0000[diff] [blame]455<h3>2.3.0: Feb 8 2001 (2.2.12 was on 25 Jan but I didn't kept track)</h3>
Daniel Veillard6e6a6cc2001-02-15 15:55:44 +0000[diff] [blame]456<ul>
457 <li>Lots of XPath bug fixes</li>
458 <li>Add a mode with Dtd lookup but without validation error reporting for
459 XSLT</li>
460 <li>Add support for text node without escaping (XSLT)</li>
461 <li>bug fixes for xmlCheckFilename</li>
462 <li>validation code bug fixes from Gary Pennington</li>
463 <li>Patch from Paul D. Smith correcting URI path normalization</li>
464 <li>Patch to allow simultaneous install of libxml-devel and
465 libxml2-devel</li>
466 <li>the example Makefile is now fixed</li>
467 <li>added HTML to the RPM packages</li>
468 <li>tree copying bugfixes</li>
469 <li>updates to Windows makefiles</li>
470 <li>optimisation patch from Bjorn Reese</li>
471</ul>
472
Daniel Veillardec70e912001-02-26 20:10:45 +0000[diff] [blame]473<h3>2.2.11: Jan 4 2001</h3>
Daniel Veillard503b8932001-01-05 06:36:31 +0000[diff] [blame]474<ul>
475 <li>bunch of bug fixes (memory I/O, xpath, ftp/http, ...)</li>
476 <li>added htmlHandleOmittedElem()</li>
477 <li>Applied Bjorn Reese's IPV6 first patch</li>
478 <li>Applied Paul D. Smith patches for validation of XInclude results</li>
Daniel Veillard82687162001-01-22 15:32:01 +0000[diff] [blame]479 <li>added XPointer xmlns() new scheme support</li>
Daniel Veillard503b8932001-01-05 06:36:31 +0000[diff] [blame]480</ul>
481
Daniel Veillard2ddd23d2000-11-25 10:42:19 +0000[diff] [blame]482<h3>2.2.10: Nov 25 2000</h3>
Daniel Veillard9d343c42000-11-25 10:12:43 +0000[diff] [blame]483<ul>
484 <li>Fix the Windows problems of 2.2.8</li>
485 <li>integrate OpenVMS patches</li>
486 <li>better handling of some nasty HTML input</li>
487 <li>Improved the XPointer implementation</li>
488 <li>integrate a number of provided patches</li>
489</ul>
490
Daniel Veillard2ddd23d2000-11-25 10:42:19 +0000[diff] [blame]491<h3>2.2.9: Nov 25 2000</h3>
492<ul>
493 <li>erroneous release :-(</li>
494</ul>
495
Daniel Veillard28929b22000-11-13 18:22:49 +0000[diff] [blame]496<h3>2.2.8: Nov 13 2000</h3>
497<ul>
498 <li>First version of <a href="http://www.w3.org/TR/xinclude">XInclude</a>
499 support</li>
500 <li>Patch in conditional section handling</li>
501 <li>updated MS compiler project</li>
502 <li>fixed some XPath problems</li>
503 <li>added an URI escaping function</li>
504 <li>some other bug fixes</li>
505</ul>
506
507<h3>2.2.7: Oct 31 2000</h3>
508<ul>
509 <li>added message redirection</li>
510 <li>XPath improvements (thanks TOM !)</li>
511 <li>xmlIOParseDTD() added</li>
512 <li>various small fixes in the HTML, URI, HTTP and XPointer support</li>
513 <li>some cleanup of the Makefile, autoconf and the distribution content</li>
514</ul>
515
Daniel Veillard29a11cc2000-10-25 13:32:39 +0000[diff] [blame]516<h3>2.2.6: Oct 25 2000:</h3>
517<ul>
518 <li>Added an hash table module, migrated a number of internal structure to
519 those</li>
520 <li>Fixed a posteriori validation problems</li>
521 <li>HTTP module cleanups</li>
522 <li>HTML parser improvements (tag errors, script/style handling, attribute
523 normalization)</li>
524 <li>coalescing of adjacent text nodes</li>
525 <li>couple of XPath bug fixes, exported the internal API</li>
526</ul>
527
Daniel Veillardab8500d2000-10-15 21:06:19 +0000[diff] [blame]528<h3>2.2.5: Oct 15 2000:</h3>
Daniel Veillard4c3a2031999-11-19 17:46:26 +0000[diff] [blame]529<ul>
Daniel Veillard189446d2000-10-13 10:23:06 +0000[diff] [blame]530 <li>XPointer implementation and testsuite</li>
531 <li>Lot of XPath fixes, added variable and functions registration, more
532 tests</li>
Daniel Veillard95189532001-07-26 18:30:26 +0000[diff] [blame]533 <li>Portability fixes, lots of enhancements toward an easy Windows build and
534 release</li>
Daniel Veillard189446d2000-10-13 10:23:06 +0000[diff] [blame]535 <li>Late validation fixes</li>
536 <li>Integrated a lot of contributed patches</li>
537 <li>added memory management docs</li>
Daniel Veillardab8500d2000-10-15 21:06:19 +0000[diff] [blame]538 <li>a performance problem when using large buffer seems fixed</li>
Daniel Veillard189446d2000-10-13 10:23:06 +0000[diff] [blame]539</ul>
540
541<h3>2.2.4: Oct 1 2000:</h3>
542<ul>
543 <li>main XPath problem fixed</li>
544 <li>Integrated portability patches for Windows</li>
545 <li>Serious bug fixes on the URI and HTML code</li>
Daniel Veillard361d8452000-04-03 19:48:13 +0000[diff] [blame]546</ul>
547
Daniel Veillardd5f97f82000-09-17 16:38:14 +0000[diff] [blame]548<h3>2.2.3: Sep 17 2000</h3>
549<ul>
550 <li>bug fixes</li>
551 <li>cleanup of entity handling code</li>
552 <li>overall review of all loops in the parsers, all sprintf usage has been
553 checked too</li>
554 <li>Far better handling of larges Dtd. Validating against Docbook XML Dtd
555 works smoothly now.</li>
556</ul>
557
558<h3>1.8.10: Sep 6 2000</h3>
559<ul>
560 <li>bug fix release for some Gnome projects</li>
561</ul>
562
563<h3>2.2.2: August 12 2000</h3>
Daniel Veillard786d7c82000-08-12 23:38:57 +0000[diff] [blame]564<ul>
565 <li>mostly bug fixes</li>
Daniel Veillardec78c0f2000-08-25 10:25:23 +0000[diff] [blame]566 <li>started adding routines to access xml parser context options</li>
Daniel Veillard786d7c82000-08-12 23:38:57 +0000[diff] [blame]567</ul>
568
Daniel Veillardd5f97f82000-09-17 16:38:14 +0000[diff] [blame]569<h3>2.2.1: July 21 2000</h3>
Daniel Veillarda2679fa2000-07-22 02:38:15 +0000[diff] [blame]570<ul>
571 <li>a purely bug fixes release</li>
572 <li>fixed an encoding support problem when parsing from a memory block</li>
573 <li>fixed a DOCTYPE parsing problem</li>
Daniel Veillard95189532001-07-26 18:30:26 +0000[diff] [blame]574 <li>removed a bug in the function allowing to override the memory allocation
575 routines</li>
Daniel Veillarda2679fa2000-07-22 02:38:15 +0000[diff] [blame]576</ul>
577
Daniel Veillardd5f97f82000-09-17 16:38:14 +0000[diff] [blame]578<h3>2.2.0: July 14 2000</h3>
Daniel Veillard94e90602000-07-17 14:38:19 +0000[diff] [blame]579<ul>
580 <li>applied a lot of portability fixes</li>
581 <li>better encoding support/cleanup and saving (content is now always
582 encoded in UTF-8)</li>
583 <li>the HTML parser now correctly handles encodings</li>
584 <li>added xmlHasProp()</li>
585 <li>fixed a serious problem with &amp;#38;</li>
586 <li>propagated the fix to FTP client</li>
587 <li>cleanup, bugfixes, etc ...</li>
588 <li>Added a page about <a href="encoding.html">libxml Internationalization
589 support</a></li>
590</ul>
591
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]592<h3>1.8.9: July 9 2000</h3>
593<ul>
594 <li>fixed the spec the RPMs should be better</li>
595 <li>fixed a serious bug in the FTP implementation, released 1.8.9 to solve
596 rpmfind users problem</li>
597</ul>
598
Daniel Veillard6388e172000-07-03 16:07:19 +0000[diff] [blame]599<h3>2.1.1: July 1 2000</h3>
600<ul>
601 <li>fixes a couple of bugs in the 2.1.0 packaging</li>
602 <li>improvements on the HTML parser</li>
603</ul>
604
Daniel Veillard3f6f7f62000-06-30 17:58:25 +0000[diff] [blame]605<h3>2.1.0 and 1.8.8: June 29 2000</h3>
606<ul>
607 <li>1.8.8 is mostly a comodity package for upgrading to libxml2 accoding to
608 <a href="upgrade.html">new instructions</a>. It fixes a nasty problem
609 about &amp;#38; charref parsing</li>
610 <li>2.1.0 also ease the upgrade from libxml v1 to the recent version. it
611 also contains numerous fixes and enhancements:
612 <ul>
613 <li>added xmlStopParser() to stop parsing</li>
614 <li>improved a lot parsing speed when there is large CDATA blocs</li>
615 <li>includes XPath patches provided by Picdar Technology</li>
616 <li>tried to fix as much as possible DtD validation and namespace
617 related problems</li>
618 <li>output to a given encoding has been added/tested</li>
619 <li>lot of various fixes</li>
620 </ul>
621 </li>
622</ul>
623
Daniel Veillarde0aed302000-04-16 08:52:20 +0000[diff] [blame]624<h3>2.0.0: Apr 12 2000</h3>
Daniel Veillard361d8452000-04-03 19:48:13 +0000[diff] [blame]625<ul>
626 <li>First public release of libxml2. If you are using libxml, it's a good
Daniel Veillarde0aed302000-04-16 08:52:20 +0000[diff] [blame]627 idea to check the 1.x to 2.x upgrade instructions. NOTE: while initally
628 scheduled for Apr 3 the relase occured only on Apr 12 due to massive
629 workload.</li>
Daniel Veillard361d8452000-04-03 19:48:13 +0000[diff] [blame]630 <li>The include are now located under $prefix/include/libxml (instead of
Daniel Veillarde0aed302000-04-16 08:52:20 +0000[diff] [blame]631 $prefix/include/gnome-xml), they also are referenced by
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]632 <pre>#include &lt;libxml/xxx.h&gt;</pre>
Daniel Veillarde0aed302000-04-16 08:52:20 +0000[diff] [blame]633 <p>instead of</p>
Daniel Veillard361d8452000-04-03 19:48:13 +0000[diff] [blame]634 <pre>#include "xxx.h"</pre>
635 </li>
Daniel Veillard8f621982000-03-20 13:07:15 +0000[diff] [blame]636 <li>a new URI module for parsing URIs and following strictly RFC 2396</li>
637 <li>the memory allocation routines used by libxml can now be overloaded
638 dynamically by using xmlMemSetup()</li>
Daniel Veillard361d8452000-04-03 19:48:13 +0000[diff] [blame]639 <li>The previously CVS only tool tester has been renamed
640 <strong>xmllint</strong> and is now installed as part of the libxml2
641 package</li>
Daniel Veillarde0aed302000-04-16 08:52:20 +0000[diff] [blame]642 <li>The I/O interface has been revamped. There is now ways to plug in
643 specific I/O modules, either at the URI scheme detection level using
644 xmlRegisterInputCallbacks() or by passing I/O functions when creating a
645 parser context using xmlCreateIOParserCtxt()</li>
646 <li>there is a C preprocessor macro LIBXML_VERSION providing the version
647 number of the libxml module in use</li>
Daniel Veillard95189532001-07-26 18:30:26 +0000[diff] [blame]648 <li>a number of optional features of libxml can now be excluded at configure
649 time (FTP/HTTP/HTML/XPath/Debug)</li>
Daniel Veillardedfb29b2000-03-14 19:59:05 +0000[diff] [blame]650</ul>
651
652<h3>2.0.0beta: Mar 14 2000</h3>
653<ul>
654 <li>This is a first Beta release of libxml version 2</li>
Daniel Veillarde356c282001-03-10 12:32:04 +0000[diff] [blame]655 <li>It's available only from<a href="ftp://xmlsoft.org/">xmlsoft.org
656 FTP</a>, it's packaged as libxml2-2.0.0beta and available as tar and
657 RPMs</li>
Daniel Veillardedfb29b2000-03-14 19:59:05 +0000[diff] [blame]658 <li>This version is now the head in the Gnome CVS base, the old one is
659 available under the tag LIB_XML_1_X</li>
660 <li>This includes a very large set of changes. Froma programmatic point of
661 view applications should not have to be modified too much, check the <a
662 href="upgrade.html">upgrade page</a></li>
663 <li>Some interfaces may changes (especially a bit about encoding).</li>
664 <li>the updates includes:
Daniel Veillard6c8b1172000-03-01 00:40:41 +0000[diff] [blame]665 <ul>
Daniel Veillardedfb29b2000-03-14 19:59:05 +0000[diff] [blame]666 <li>fix I18N support. ISO-Latin-x/UTF-8/UTF-16 (nearly) seems correctly
667 handled now</li>
Daniel Veillard95189532001-07-26 18:30:26 +0000[diff] [blame]668 <li>Better handling of entities, especially well formedness checking and
669 proper PEref extensions in external subsets</li>
Daniel Veillard6c8b1172000-03-01 00:40:41 +0000[diff] [blame]670 <li>DTD conditional sections</li>
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]671 <li>Validation now correcly handle entities content</li>
Daniel Veillard6c8b1172000-03-01 00:40:41 +0000[diff] [blame]672 <li><a href="http://rpmfind.net/tools/gdome/messages/0039.html">change
673 structures to accomodate DOM</a></li>
Daniel Veillard6c8b1172000-03-01 00:40:41 +0000[diff] [blame]674 </ul>
675 </li>
Daniel Veillardedfb29b2000-03-14 19:59:05 +0000[diff] [blame]676 <li>Serious progress were made toward compliance, <a
677 href="conf/result.html">here are the result of the test</a> against the
678 OASIS testsuite (except the japanese tests since I don't support that
679 encoding yet). This URL is rebuilt every couple of hours using the CVS
680 head version.</li>
Daniel Veillarde41f2b72000-01-30 20:00:07 +0000[diff] [blame]681</ul>
682
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]683<h3>1.8.7: Mar 6 2000</h3>
684<ul>
685 <li>This is a bug fix release:</li>
686 <li>It is possible to disable the ignorable blanks heuristic used by
687 libxml-1.x, a new function xmlKeepBlanksDefault(0) will allow this. Note
Daniel Veillard95189532001-07-26 18:30:26 +0000[diff] [blame]688 that for adherence to XML spec, this behaviour will be disabled by default
689 in 2.x . The same function will allow to keep compatibility for old
690 code.</li>
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]691 <li>Blanks in &lt;a&gt; &lt;/a&gt; constructs are not ignored anymore,
692 avoiding heuristic is really the Right Way :-\</li>
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]693 <li>The unchecked use of snprintf which was breaking libxml-1.8.6
694 compilation on some platforms has been fixed</li>
695 <li>nanoftp.c nanohttp.c: Fixed '#' and '?' stripping when processing
696 URIs</li>
697</ul>
698
Daniel Veillarde41f2b72000-01-30 20:00:07 +0000[diff] [blame]699<h3>1.8.6: Jan 31 2000</h3>
700<ul>
701 <li>added a nanoFTP transport module, debugged until the new version of <a
702 href="http://rpmfind.net/linux/rpm2html/rpmfind.html">rpmfind</a> can use
703 it without troubles</li>
Daniel Veillardda07c342000-01-25 18:31:22 +0000[diff] [blame]704</ul>
705
706<h3>1.8.5: Jan 21 2000</h3>
707<ul>
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]708 <li>adding APIs to parse a well balanced chunk of XML (production <a
Daniel Veillard95189532001-07-26 18:30:26 +0000[diff] [blame]709 href="http://www.w3.org/TR/REC-xml#NT-content">[43] content</a> of the XML
710 spec)</li>
Daniel Veillard461a66c2000-01-18 18:01:01 +0000[diff] [blame]711 <li>fixed a hideous bug in xmlGetProp pointed by Rune.Djurhuus@fast.no</li>
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]712 <li>Jody Goldberg &lt;jgoldberg@home.com&gt; provided another patch trying
713 to solve the zlib checks problems</li>
Daniel Veillard461a66c2000-01-18 18:01:01 +0000[diff] [blame]714 <li>The current state in gnome CVS base is expected to ship as 1.8.5 with
715 gnumeric soon</li>
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]716</ul>
717
718<h3>1.8.4: Jan 13 2000</h3>
719<ul>
720 <li>bug fixes, reintroduced xmlNewGlobalNs(), fixed xmlNewNs()</li>
721 <li>all exit() call should have been removed from libxml</li>
722 <li>fixed a problem with INCLUDE_WINSOCK on WIN32 platform</li>
723 <li>added newDocFragment()</li>
Daniel Veillardf84f71f2000-01-05 19:54:23 +0000[diff] [blame]724</ul>
725
726<h3>1.8.3: Jan 5 2000</h3>
727<ul>
728 <li>a Push interface for the XML and HTML parsers</li>
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]729 <li>a shell-like interface to the document tree (try tester --shell :-)</li>
Daniel Veillarddbfd6411999-12-28 16:35:14 +0000[diff] [blame]730 <li>lots of bug fixes and improvement added over XMas hollidays</li>
Daniel Veillard437b87b2000-01-03 17:30:46 +0000[diff] [blame]731 <li>fixed the DTD parsing code to work with the xhtml DTD</li>
Daniel Veillardf84f71f2000-01-05 19:54:23 +0000[diff] [blame]732 <li>added xmlRemoveProp(), xmlRemoveID() and xmlRemoveRef()</li>
733 <li>Fixed bugs in xmlNewNs()</li>
Daniel Veillard437b87b2000-01-03 17:30:46 +0000[diff] [blame]734 <li>External entity loading code has been revamped, now it uses
Daniel Veillardf84f71f2000-01-05 19:54:23 +0000[diff] [blame]735 xmlLoadExternalEntity(), some fix on entities processing were added</li>
Daniel Veillard437b87b2000-01-03 17:30:46 +0000[diff] [blame]736 <li>cleaned up WIN32 includes of socket stuff</li>
Daniel Veillard5cb5ab81999-12-21 15:35:29 +0000[diff] [blame]737</ul>
738
739<h3>1.8.2: Dec 21 1999</h3>
740<ul>
Daniel Veillardb24054a1999-12-18 15:32:46 +0000[diff] [blame]741 <li>I got another problem with includes and C++, I hope this issue is fixed
742 for good this time</li>
Daniel Veillard5cb5ab81999-12-21 15:35:29 +0000[diff] [blame]743 <li>Added a few tree modification functions: xmlReplaceNode,
744 xmlAddPrevSibling, xmlAddNextSibling, xmlNodeSetName and
745 xmlDocSetRootElement</li>
746 <li>Tried to improve the HTML output with help from <a
747 href="mailto:clahey@umich.edu">Chris Lahey</a></li>
Daniel Veillarde4e51311999-12-18 15:32:46 +0000[diff] [blame]748</ul>
Daniel Veillardb24054a1999-12-18 15:32:46 +0000[diff] [blame]749
Daniel Veillarde4e51311999-12-18 15:32:46 +0000[diff] [blame]750<h3>1.8.1: Dec 18 1999</h3>
751<ul>
752 <li>various patches to avoid troubles when using libxml with C++ compilers
753 the "namespace" keyword and C escaping in include files</li>
754 <li>a problem in one of the core macros IS_CHAR was corrected</li>
755 <li>fixed a bug introduced in 1.8.0 breaking default namespace processing,
756 and more specifically the Dia application</li>
Daniel Veillard944b5ff1999-12-15 19:08:24 +0000[diff] [blame]757 <li>fixed a posteriori validation (validation after parsing, or by using a
758 Dtd not specified in the original document)</li>
Daniel Veillardb24054a1999-12-18 15:32:46 +0000[diff] [blame]759 <li>fixed a bug in</li>
Daniel Veillard10a2c651999-12-12 13:03:50 +0000[diff] [blame]760</ul>
761
762<h3>1.8.0: Dec 12 1999</h3>
763<ul>
764 <li>cleanup, especially memory wise</li>
765 <li>the parser should be more reliable, especially the HTML one, it should
766 not crash, whatever the input !</li>
767 <li>Integrated various patches, especially a speedup improvement for large
768 dataset from <a href="mailto:cnygard@bellatlantic.net">Carl Nygard</a>,
769 configure with --with-buffers to enable them.</li>
770 <li>attribute normalization, oops should have been added long ago !</li>
771 <li>attributes defaulted from Dtds should be available, xmlSetProp() now
772 does entities escapting by default.</li>
Daniel Veillard4c3a2031999-11-19 17:46:26 +0000[diff] [blame]773</ul>
Daniel Veillard35008381999-10-25 13:15:52 +0000[diff] [blame]774
775<h3>1.7.4: Oct 25 1999</h3>
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]776<ul>
Daniel Veillard35008381999-10-25 13:15:52 +0000[diff] [blame]777 <li>Lots of HTML improvement</li>
778 <li>Fixed some errors when saving both XML and HTML</li>
779 <li>More examples, the regression tests should now look clean</li>
780 <li>Fixed a bug with contiguous charref</li>
781</ul>
782
783<h3>1.7.3: Sep 29 1999</h3>
784<ul>
785 <li>portability problems fixed</li>
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]786 <li>snprintf was used unconditionnally, leading to link problems on system
Daniel Veillard35008381999-10-25 13:15:52 +0000[diff] [blame]787 were it's not available, fixed</li>
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]788</ul>
789
790<h3>1.7.1: Sep 24 1999</h3>
791<ul>
792 <li>The basic type for strings manipulated by libxml has been renamed in
793 1.7.1 from <strong>CHAR</strong> to <strong>xmlChar</strong>. The reason
Daniel Veillard95189532001-07-26 18:30:26 +0000[diff] [blame]794 is that CHAR was conflicting with a predefined type on Windows. However on
795 non WIN32 environment, compatibility is provided by the way of a
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]796 <strong>#define </strong>.</li>
797 <li>Changed another error : the use of a structure field called errno, and
798 leading to troubles on platforms where it's a macro</li>
799</ul>
800
801<h3>1.7.0: sep 23 1999</h3>
802<ul>
803 <li>Added the ability to fetch remote DTD or parsed entities, see the <a
Daniel Veillard9cb5ff42001-01-29 08:22:21 +0000[diff] [blame]804 href="html/libxml-nanohttp.html">nanohttp</a> module.</li>
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]805 <li>Added an errno to report errors by another mean than a simple printf
806 like callback</li>
807 <li>Finished ID/IDREF support and checking when validation</li>
808 <li>Serious memory leaks fixed (there is now a <a
Daniel Veillard9cb5ff42001-01-29 08:22:21 +0000[diff] [blame]809 href="html/libxml-xmlmemory.html">memory wrapper</a> module)</li>
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]810 <li>Improvement of <a href="http://www.w3.org/TR/xpath">XPath</a>
811 implementation</li>
812 <li>Added an HTML parser front-end</li>
813</ul>
814
815<h2><a name="XML">XML</a></h2>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]816
Daniel Veillard402e8c82000-02-29 22:57:47 +0000[diff] [blame]817<p><a href="http://www.w3.org/TR/REC-xml">XML is a standard</a> for
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]818markup-based structured documents. Here is <a name="example">an example XML
819document</a>:</p>
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]820<pre>&lt;?xml version="1.0"?&gt;
821&lt;EXAMPLE prop1="gnome is great" prop2="&amp;amp; linux too"&gt;
822 &lt;head&gt;
823 &lt;title&gt;Welcome to Gnome&lt;/title&gt;
824 &lt;/head&gt;
825 &lt;chapter&gt;
826 &lt;title&gt;The Linux adventure&lt;/title&gt;
827 &lt;p&gt;bla bla bla ...&lt;/p&gt;
828 &lt;image href="linus.gif"/&gt;
829 &lt;p&gt;...&lt;/p&gt;
830 &lt;/chapter&gt;
831&lt;/EXAMPLE&gt;</pre>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]832
Daniel Veillard402e8c82000-02-29 22:57:47 +0000[diff] [blame]833<p>The first line specifies that it's an XML document and gives useful
834information about its encoding. Then the document is a text format whose
835structure is specified by tags between brackets. <strong>Each tag opened has
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]836to be closed</strong>. XML is pedantic about this. However, if a tag is empty
Daniel Veillard95189532001-07-26 18:30:26 +0000[diff] [blame]837(no content), a single tag can serve as both the opening and closing tag if it
838ends with <code>/&gt;</code> rather than with <code>&gt;</code>. Note that,
839for example, the image tag has no content (just an attribute) and is closed by
840ending the tag with <code>/&gt;</code>.</p>
Daniel Veillardccb09631998-10-27 06:21:04 +0000[diff] [blame]841
Daniel Veillard402e8c82000-02-29 22:57:47 +0000[diff] [blame]842<p>XML can be applied sucessfully to a wide range of uses, from long term
Daniel Veillard95189532001-07-26 18:30:26 +0000[diff] [blame]843structured document maintenance (where it follows the steps of SGML) to simple
844data encoding mechanisms like configuration file formatting (glade),
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]845spreadsheets (gnumeric), or even shorter lived documents such as WebDAV where
846it is used to encode remote calls between a client and a server.</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]847
Daniel Veillard82687162001-01-22 15:32:01 +0000[diff] [blame]848<h2><a name="XSLT">XSLT</a></h2>
849
Daniel Veillard6e6a6cc2001-02-15 15:55:44 +0000[diff] [blame]850<p>Check <a href="http://xmlsoft.org/XSLT">the separate libxslt page</a></p>
851
Daniel Veillard95189532001-07-26 18:30:26 +0000[diff] [blame]852<p><a href="http://www.w3.org/TR/xslt">XSL Transformations</a>, is a language
853for transforming XML documents into other XML documents (or HTML/textual
854output).</p>
Daniel Veillard82687162001-01-22 15:32:01 +0000[diff] [blame]855
856<p>A separate library called libxslt is being built on top of libxml2. This
857module "libxslt" can be found in the Gnome CVS base too.</p>
858
Daniel Veillard383b1472001-01-23 11:39:52 +0000[diff] [blame]859<p>You can check the <a
Daniel Veillard95189532001-07-26 18:30:26 +0000[diff] [blame]860href="http://cvs.gnome.org/lxr/source/libxslt/FEATURES">features</a> supported
861and the progresses on the <a
Daniel Veillard82687162001-01-22 15:32:01 +0000[diff] [blame]862href="http://cvs.gnome.org/lxr/source/libxslt/ChangeLog">Changelog</a></p>
863
Daniel Veillard4540be42000-08-19 16:40:28 +0000[diff] [blame]864<h2>An overview of libxml architecture</h2>
865
Daniel Veillardec70e912001-02-26 20:10:45 +0000[diff] [blame]866<p>Libxml is made of multiple components; some of them are optional, and most
867of the block interfaces are public. The main components are:</p>
Daniel Veillard4540be42000-08-19 16:40:28 +0000[diff] [blame]868<ul>
869 <li>an Input/Output layer</li>
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]870 <li>FTP and HTTP client layers (optional)</li>
Daniel Veillard4540be42000-08-19 16:40:28 +0000[diff] [blame]871 <li>an Internationalization layer managing the encodings support</li>
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]872 <li>a URI module</li>
Daniel Veillard4540be42000-08-19 16:40:28 +0000[diff] [blame]873 <li>the XML parser and its basic SAX interface</li>
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]874 <li>an HTML parser using the same SAX interface (optional)</li>
Daniel Veillard4540be42000-08-19 16:40:28 +0000[diff] [blame]875 <li>a SAX tree module to build an in-memory DOM representation</li>
876 <li>a tree module to manipulate the DOM representation</li>
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]877 <li>a validation module using the DOM representation (optional)</li>
Daniel Veillard4540be42000-08-19 16:40:28 +0000[diff] [blame]878 <li>an XPath module for global lookup in a DOM representation
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]879 (optional)</li>
880 <li>a debug module (optional)</li>
Daniel Veillard4540be42000-08-19 16:40:28 +0000[diff] [blame]881</ul>
882
883<p>Graphically this gives the following:</p>
884
885<p><img src="libxml.gif" alt="a graphical view of the various"></p>
886
887<p></p>
888
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]889<h2><a name="tree">The tree output</a></h2>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]890
891<p>The parser returns a tree built during the document analysis. The value
Daniel Veillard402e8c82000-02-29 22:57:47 +0000[diff] [blame]892returned is an <strong>xmlDocPtr</strong> (i.e., a pointer to an
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]893<strong>xmlDoc</strong> structure). This structure contains information such
Daniel Veillard306be992000-07-03 12:38:45 +0000[diff] [blame]894as the file name, the document type, and a <strong>children</strong> pointer
895which is the root of the document (or more exactly the first child under the
896root which is the document). The tree is made of <strong>xmlNode</strong>s,
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]897chained in double-linked lists of siblings and with a children&lt;-&gt;parent
Daniel Veillard306be992000-07-03 12:38:45 +0000[diff] [blame]898relationship. An xmlNode can also carry properties (a chain of xmlAttr
899structures). An attribute may have a value which is a list of TEXT or
900ENTITY_REF nodes.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]901
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]902<p>Here is an example (erroneous with respect to the XML spec since there
903should be only one ELEMENT under the root):</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]904
905<p><img src="structure.gif" alt=" structure.gif "></p>
906
907<p>In the source package there is a small program (not installed by default)
Daniel Veillard361d8452000-04-03 19:48:13 +0000[diff] [blame]908called <strong>xmllint</strong> which parses XML files given as argument and
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]909prints them back as parsed. This is useful for detecting errors both in XML
910code and in the XML parser itself. It has an option <strong>--debug</strong>
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]911which prints the actual in-memory structure of the document; here is the
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]912result with the <a href="#example">example</a> given before:</p>
Daniel Veillard10c6a8f1998-10-28 01:00:12 +0000[diff] [blame]913<pre>DOCUMENT
914version=1.0
915standalone=true
916 ELEMENT EXAMPLE
917 ATTRIBUTE prop1
918 TEXT
919 content=gnome is great
920 ATTRIBUTE prop2
921 ENTITY_REF
922 TEXT
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]923 content= linux too
Daniel Veillard402e8c82000-02-29 22:57:47 +0000[diff] [blame]924 ELEMENT head
Daniel Veillard10c6a8f1998-10-28 01:00:12 +0000[diff] [blame]925 ELEMENT title
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]926 TEXT
927 content=Welcome to Gnome
Daniel Veillard10c6a8f1998-10-28 01:00:12 +0000[diff] [blame]928 ELEMENT chapter
929 ELEMENT title
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]930 TEXT
931 content=The Linux adventure
Daniel Veillard10c6a8f1998-10-28 01:00:12 +0000[diff] [blame]932 ELEMENT p
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]933 TEXT
934 content=bla bla bla ...
Daniel Veillard10c6a8f1998-10-28 01:00:12 +0000[diff] [blame]935 ELEMENT image
936 ATTRIBUTE href
937 TEXT
938 content=linus.gif
939 ELEMENT p
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]940 TEXT
941 content=...</pre>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]942
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]943<p>This should be useful for learning the internal representation model.</p>
Daniel Veillardccb09631998-10-27 06:21:04 +0000[diff] [blame]944
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]945<h2><a name="interface">The SAX interface</a></h2>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]946
Daniel Veillard402e8c82000-02-29 22:57:47 +0000[diff] [blame]947<p>Sometimes the DOM tree output is just too large to fit reasonably into
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]948memory. In that case (and if you don't expect to save back the XML document
Daniel Veillard95189532001-07-26 18:30:26 +0000[diff] [blame]949loaded using libxml), it's better to use the SAX interface of libxml. SAX is a
950<strong>callback-based interface</strong> to the parser. Before parsing, the
951application layer registers a customized set of callbacks which are called by
952the library as it progresses through the XML input.</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]953
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]954<p>To get more detailed step-by-step guidance on using the SAX interface of
Daniel Veillard4540be42000-08-19 16:40:28 +0000[diff] [blame]955libxml, see the <a
956href="http://www.daa.com.au/~james/gnome/xml-sax/xml-sax.html">nice
957documentation</a>.written by <a href="mailto:james@daa.com.au">James
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]958Henstridge</a>.</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]959
960<p>You can debug the SAX behaviour by using the <strong>testSAX</strong>
961program located in the gnome-xml module (it's usually not shipped in the
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]962binary packages of libxml, but you can find it in the tar source
Daniel Veillard402e8c82000-02-29 22:57:47 +0000[diff] [blame]963distribution). Here is the sequence of callbacks that would be reported by
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]964testSAX when parsing the example XML document shown earlier:</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]965<pre>SAX.setDocumentLocator()
966SAX.startDocument()
967SAX.getEntity(amp)
968SAX.startElement(EXAMPLE, prop1='gnome is great', prop2='&amp;amp; linux too')
969SAX.characters( , 3)
970SAX.startElement(head)
971SAX.characters( , 4)
972SAX.startElement(title)
973SAX.characters(Welcome to Gnome, 16)
974SAX.endElement(title)
975SAX.characters( , 3)
976SAX.endElement(head)
977SAX.characters( , 3)
978SAX.startElement(chapter)
979SAX.characters( , 4)
980SAX.startElement(title)
981SAX.characters(The Linux adventure, 19)
982SAX.endElement(title)
983SAX.characters( , 4)
984SAX.startElement(p)
985SAX.characters(bla bla bla ..., 15)
986SAX.endElement(p)
987SAX.characters( , 4)
988SAX.startElement(image, href='linus.gif')
989SAX.endElement(image)
990SAX.characters( , 4)
991SAX.startElement(p)
992SAX.characters(..., 3)
993SAX.endElement(p)
994SAX.characters( , 3)
995SAX.endElement(chapter)
996SAX.characters( , 1)
997SAX.endElement(EXAMPLE)
998SAX.endDocument()</pre>
999
Daniel Veillardec70e912001-02-26 20:10:45 +0000[diff] [blame]1000<p>Most of the other interfaces of libxml are based on the DOM tree-building
1001facility, so nearly everything up to the end of this document presupposes the
1002use of the standard DOM tree build. Note that the DOM tree itself is built by
1003a set of registered default callbacks, without internal specific
1004interface.</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]1005
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]1006<h2><a name="library">The XML library interfaces</a></h2>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]1007
1008<p>This section is directly intended to help programmers getting bootstrapped
Daniel Veillard95189532001-07-26 18:30:26 +0000[diff] [blame]1009using the XML library from the C language. It is not intended to be extensive.
1010I hope the automatically generated documents will provide the completeness
1011required, but as a separate set of documents. The interfaces of the XML
1012library are by principle low level, there is nearly zero abstraction. Those
1013interested in a higher level API should <a href="#DOM">look at DOM</a>.</p>
Daniel Veillardccb09631998-10-27 06:21:04 +0000[diff] [blame]1014
Daniel Veillard9cb5ff42001-01-29 08:22:21 +0000[diff] [blame]1015<p>The <a href="html/libxml-parser.html">parser interfaces for XML</a> are
1016separated from the <a href="html/libxml-htmlparser.html">HTML parser
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]1017interfaces</a>. Let's have a look at how the XML parser can be called:</p>
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]1018
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]1019<h3><a name="Invoking">Invoking the parser : the pull method</a></h3>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]1020
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]1021<p>Usually, the first thing to do is to read an XML input. The parser accepts
1022documents either from in-memory strings or from files. The functions are
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]1023defined in "parser.h":</p>
Daniel Veillard10c6a8f1998-10-28 01:00:12 +0000[diff] [blame]1024<dl>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]1025 <dt><code>xmlDocPtr xmlParseMemory(char *buffer, int size);</code></dt>
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]1026 <dd><p>Parse a null-terminated string containing the document.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]1027 </dd>
Daniel Veillard10c6a8f1998-10-28 01:00:12 +0000[diff] [blame]1028</dl>
1029<dl>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]1030 <dt><code>xmlDocPtr xmlParseFile(const char *filename);</code></dt>
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]1031 <dd><p>Parse an XML document contained in a (possibly compressed)
1032 file.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]1033 </dd>
Daniel Veillard10c6a8f1998-10-28 01:00:12 +0000[diff] [blame]1034</dl>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]1035
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]1036<p>The parser returns a pointer to the document structure (or NULL in case of
Daniel Veillard10c6a8f1998-10-28 01:00:12 +0000[diff] [blame]1037failure).</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]1038
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]1039<h3 id="Invoking1">Invoking the parser: the push method</h3>
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]1040
Daniel Veillard95189532001-07-26 18:30:26 +0000[diff] [blame]1041<p>In order for the application to keep the control when the document is being
1042fetched (which is common for GUI based programs) libxml provides a push
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]1043interface, too, as of version 1.8.3. Here are the interface functions:</p>
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]1044<pre>xmlParserCtxtPtr xmlCreatePushParserCtxt(xmlSAXHandlerPtr sax,
1045 void *user_data,
1046 const char *chunk,
1047 int size,
1048 const char *filename);
1049int xmlParseChunk (xmlParserCtxtPtr ctxt,
1050 const char *chunk,
1051 int size,
1052 int terminate);</pre>
1053
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]1054<p>and here is a simple example showing how to use the interface:</p>
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]1055<pre> FILE *f;
1056
1057 f = fopen(filename, "r");
1058 if (f != NULL) {
1059 int res, size = 1024;
1060 char chars[1024];
1061 xmlParserCtxtPtr ctxt;
1062
1063 res = fread(chars, 1, 4, f);
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]1064 if (res &gt; 0) {
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]1065 ctxt = xmlCreatePushParserCtxt(NULL, NULL,
1066 chars, res, filename);
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]1067 while ((res = fread(chars, 1, size, f)) &gt; 0) {
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]1068 xmlParseChunk(ctxt, chars, res, 0);
1069 }
1070 xmlParseChunk(ctxt, chars, 0, 1);
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]1071 doc = ctxt-&gt;myDoc;
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]1072 xmlFreeParserCtxt(ctxt);
1073 }
1074 }</pre>
1075
Daniel Veillardec70e912001-02-26 20:10:45 +0000[diff] [blame]1076<p>The HTML parser embedded into libxml also has a push interface; the
1077functions are just prefixed by "html" rather than "xml".</p>
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]1078
1079<h3 id="Invoking2">Invoking the parser: the SAX interface</h3>
1080
Daniel Veillardec70e912001-02-26 20:10:45 +0000[diff] [blame]1081<p>The tree-building interface makes the parser memory-hungry, first loading
1082the document in memory and then building the tree itself. Reading a document
1083without building the tree is possible using the SAX interfaces (see SAX.h and
1084<a href="http://www.daa.com.au/~james/gnome/xml-sax/xml-sax.html">James
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]1085Henstridge's documentation</a>). Note also that the push interface can be
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]1086limited to SAX: just use the two first arguments of
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]1087<code>xmlCreatePushParserCtxt()</code>.</p>
Daniel Veillardccb09631998-10-27 06:21:04 +0000[diff] [blame]1088
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]1089<h3><a name="Building">Building a tree from scratch</a></h3>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]1090
1091<p>The other way to get an XML tree in memory is by building it. Basically
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]1092there is a set of functions dedicated to building new elements. (These are
Daniel Veillard95189532001-07-26 18:30:26 +0000[diff] [blame]1093also described in &lt;libxml/tree.h&gt;.) For example, here is a piece of code
1094that produces the XML document used in the previous examples:</p>
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]1095<pre> #include &lt;libxml/tree.h&gt;
Daniel Veillard361d8452000-04-03 19:48:13 +0000[diff] [blame]1096 xmlDocPtr doc;
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]1097 xmlNodePtr tree, subtree;
1098
1099 doc = xmlNewDoc("1.0");
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]1100 doc-&gt;children = xmlNewDocNode(doc, NULL, "EXAMPLE", NULL);
1101 xmlSetProp(doc-&gt;children, "prop1", "gnome is great");
1102 xmlSetProp(doc-&gt;children, "prop2", "&amp; linux too");
1103 tree = xmlNewChild(doc-&gt;children, NULL, "head", NULL);
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]1104 subtree = xmlNewChild(tree, NULL, "title", "Welcome to Gnome");
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]1105 tree = xmlNewChild(doc-&gt;children, NULL, "chapter", NULL);
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]1106 subtree = xmlNewChild(tree, NULL, "title", "The Linux adventure");
1107 subtree = xmlNewChild(tree, NULL, "p", "bla bla bla ...");
1108 subtree = xmlNewChild(tree, NULL, "image", NULL);
1109 xmlSetProp(subtree, "href", "linus.gif");</pre>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]1110
1111<p>Not really rocket science ...</p>
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]1112
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]1113<h3><a name="Traversing">Traversing the tree</a></h3>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]1114
Daniel Veillard9cb5ff42001-01-29 08:22:21 +0000[diff] [blame]1115<p>Basically by <a href="html/libxml-tree.html">including "tree.h"</a> your
Daniel Veillard95189532001-07-26 18:30:26 +0000[diff] [blame]1116code has access to the internal structure of all the elements of the tree. The
1117names should be somewhat simple like <strong>parent</strong>,
Daniel Veillard306be992000-07-03 12:38:45 +0000[diff] [blame]1118<strong>children</strong>, <strong>next</strong>, <strong>prev</strong>,
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]1119<strong>properties</strong>, etc... For example, still with the previous
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]1120example:</p>
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]1121<pre><code>doc-&gt;children-&gt;children-&gt;children</code></pre>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]1122
1123<p>points to the title element,</p>
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]1124<pre>doc-&gt;children-&gt;children-&gt;next-&gt;children-&gt;children</pre>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]1125
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]1126<p>points to the text node containing the chapter title "The Linux
1127adventure".</p>
Daniel Veillard10c6a8f1998-10-28 01:00:12 +0000[diff] [blame]1128
Daniel Veillardb24054a1999-12-18 15:32:46 +0000[diff] [blame]1129<p><strong>NOTE</strong>: XML allows <em>PI</em>s and <em>comments</em> to be
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]1130present before the document root, so <code>doc-&gt;children</code> may point
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]1131to an element which is not the document Root Element; a function
Daniel Veillard5cb5ab81999-12-21 15:35:29 +0000[diff] [blame]1132<code>xmlDocGetRootElement()</code> was added for this purpose.</p>
Daniel Veillardb24054a1999-12-18 15:32:46 +0000[diff] [blame]1133
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]1134<h3><a name="Modifying">Modifying the tree</a></h3>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]1135
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]1136<p>Functions are provided for reading and writing the document content. Here
Daniel Veillard9cb5ff42001-01-29 08:22:21 +0000[diff] [blame]1137is an excerpt from the <a href="html/libxml-tree.html">tree API</a>:</p>
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]1138<dl>
Daniel Veillarddd6b3671999-09-23 22:19:22 +0000[diff] [blame]1139 <dt><code>xmlAttrPtr xmlSetProp(xmlNodePtr node, const xmlChar *name, const
1140 xmlChar *value);</code></dt>
Daniel Veillard95189532001-07-26 18:30:26 +0000[diff] [blame]1141 <dd><p>This sets (or changes) an attribute carried by an ELEMENT node. The
1142 value can be NULL.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]1143 </dd>
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]1144</dl>
1145<dl>
Daniel Veillarddd6b3671999-09-23 22:19:22 +0000[diff] [blame]1146 <dt><code>const xmlChar *xmlGetProp(xmlNodePtr node, const xmlChar
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]1147 *name);</code></dt>
Daniel Veillardc92c3042000-09-29 02:42:04 +0000[diff] [blame]1148 <dd><p>This function returns a pointer to new copy of the property
1149 content. Note that the user must deallocate the result.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]1150 </dd>
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]1151</dl>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]1152
Daniel Veillard95189532001-07-26 18:30:26 +0000[diff] [blame]1153<p>Two functions are provided for reading and writing the text associated with
1154elements:</p>
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]1155<dl>
Daniel Veillarddd6b3671999-09-23 22:19:22 +0000[diff] [blame]1156 <dt><code>xmlNodePtr xmlStringGetNodeList(xmlDocPtr doc, const xmlChar
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]1157 *value);</code></dt>
Daniel Veillardec70e912001-02-26 20:10:45 +0000[diff] [blame]1158 <dd><p>This function takes an "external" string and converts it to one
1159 text node or possibly to a list of entity and text nodes. All
1160 non-predefined entity references like &amp;Gnome; will be stored
1161 internally as entity nodes, hence the result of the function may not be
1162 a single node.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]1163 </dd>
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]1164</dl>
1165<dl>
Daniel Veillarddd6b3671999-09-23 22:19:22 +0000[diff] [blame]1166 <dt><code>xmlChar *xmlNodeListGetString(xmlDocPtr doc, xmlNodePtr list, int
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]1167 inLine);</code></dt>
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]1168 <dd><p>This function is the inverse of
1169 <code>xmlStringGetNodeList()</code>. It generates a new string
1170 containing the content of the text and entity nodes. Note the extra
1171 argument inLine. If this argument is set to 1, the function will expand
1172 entity references. For example, instead of returning the &amp;Gnome;
1173 XML encoding in the string, it will substitute it with its value (say,
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]1174 "GNU Network Object Model Environment").</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]1175 </dd>
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]1176</dl>
Daniel Veillard10c6a8f1998-10-28 01:00:12 +0000[diff] [blame]1177
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]1178<h3><a name="Saving">Saving a tree</a></h3>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]1179
1180<p>Basically 3 options are possible:</p>
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]1181<dl>
Daniel Veillarddd6b3671999-09-23 22:19:22 +0000[diff] [blame]1182 <dt><code>void xmlDocDumpMemory(xmlDocPtr cur, xmlChar**mem, int
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]1183 *size);</code></dt>
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]1184 <dd><p>Returns a buffer into which the document has been saved.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]1185 </dd>
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]1186</dl>
1187<dl>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]1188 <dt><code>extern void xmlDocDump(FILE *f, xmlDocPtr doc);</code></dt>
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]1189 <dd><p>Dumps a document to an open file descriptor.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]1190 </dd>
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]1191</dl>
1192<dl>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]1193 <dt><code>int xmlSaveFile(const char *filename, xmlDocPtr cur);</code></dt>
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]1194 <dd><p>Saves the document to a file. In this case, the compression
1195 interface is triggered if it has been turned on.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]1196 </dd>
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]1197</dl>
Daniel Veillard10c6a8f1998-10-28 01:00:12 +0000[diff] [blame]1198
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]1199<h3><a name="Compressio">Compression</a></h3>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]1200
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]1201<p>The library transparently handles compression when doing file-based
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]1202accesses. The level of compression on saves can be turned on either globally
1203or individually for one file:</p>
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]1204<dl>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]1205 <dt><code>int xmlGetDocCompressMode (xmlDocPtr doc);</code></dt>
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]1206 <dd><p>Gets the document compression ratio (0-9).</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]1207 </dd>
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]1208</dl>
1209<dl>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]1210 <dt><code>void xmlSetDocCompressMode (xmlDocPtr doc, int mode);</code></dt>
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]1211 <dd><p>Sets the document compression ratio.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]1212 </dd>
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]1213</dl>
1214<dl>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]1215 <dt><code>int xmlGetCompressMode(void);</code></dt>
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]1216 <dd><p>Gets the default compression ratio.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]1217 </dd>
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]1218</dl>
1219<dl>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]1220 <dt><code>void xmlSetCompressMode(int mode);</code></dt>
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]1221 <dd><p>Sets the default compression ratio.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]1222 </dd>
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]1223</dl>
1224
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]1225<h2><a name="Entities">Entities or no entities</a></h2>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]1226
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]1227<p>Entities in principle are similar to simple C macros. An entity defines an
1228abbreviation for a given string that you can reuse many times throughout the
1229content of your document. Entities are especially useful when a given string
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]1230may occur frequently within a document, or to confine the change needed to a
1231document to a restricted area in the internal subset of the document (at the
1232beginning). Example:</p>
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]1233<pre>1 &lt;?xml version="1.0"?&gt;
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]12342 &lt;!DOCTYPE EXAMPLE SYSTEM "example.dtd" [
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]12353 &lt;!ENTITY xml "Extensible Markup Language"&gt;
12364 ]&gt;
12375 &lt;EXAMPLE&gt;
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]12386 &amp;xml;
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]12397 &lt;/EXAMPLE&gt;</pre>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]1240
1241<p>Line 3 declares the xml entity. Line 6 uses the xml entity, by prefixing
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]1242its name with '&amp;' and following it by ';' without any spaces added. There
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]1243are 5 predefined entities in libxml allowing you to escape charaters with
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]1244predefined meaning in some parts of the xml document content:
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]1245<strong>&amp;lt;</strong> for the character '&lt;', <strong>&amp;gt;</strong>
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]1246for the character '&gt;', <strong>&amp;apos;</strong> for the character ''',
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]1247<strong>&amp;quot;</strong> for the character '"', and
1248<strong>&amp;amp;</strong> for the character '&amp;'.</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]1249
1250<p>One of the problems related to entities is that you may want the parser to
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]1251substitute an entity's content so that you can see the replacement text in
1252your application. Or you may prefer to keep entity references as such in the
1253content to be able to save the document back without losing this usually
Daniel Veillard95189532001-07-26 18:30:26 +0000[diff] [blame]1254precious information (if the user went through the pain of explicitly defining
1255entities, he may have a a rather negative attitude if you blindly susbtitute
1256them as saving time). The <a
Daniel Veillard9cb5ff42001-01-29 08:22:21 +0000[diff] [blame]1257href="html/libxml-parser.html#XMLSUBSTITUTEENTITIESDEFAULT">xmlSubstituteEntitiesDefault()</a>
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]1258function allows you to check and change the behaviour, which is to not
1259substitute entities by default.</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]1260
1261<p>Here is the DOM tree built by libxml for the previous document in the
1262default case:</p>
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]1263<pre>/gnome/src/gnome-xml -&gt; ./xmllint --debug test/ent1
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]1264DOCUMENT
1265version=1.0
1266 ELEMENT EXAMPLE
1267 TEXT
1268 content=
1269 ENTITY_REF
1270 INTERNAL_GENERAL_ENTITY xml
1271 content=Extensible Markup Language
1272 TEXT
1273 content=</pre>
1274
1275<p>And here is the result when substituting entities:</p>
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]1276<pre>/gnome/src/gnome-xml -&gt; ./tester --debug --noent test/ent1
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]1277DOCUMENT
1278version=1.0
1279 ELEMENT EXAMPLE
1280 TEXT
1281 content= Extensible Markup Language</pre>
1282
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]1283<p>So, entities or no entities? Basically, it depends on your use case. I
1284suggest that you keep the non-substituting default behaviour and avoid using
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]1285entities in your XML document or data if you are not willing to handle the
1286entity references elements in the DOM tree.</p>
1287
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]1288<p>Note that at save time libxml enforces the conversion of the predefined
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]1289entities where necessary to prevent well-formedness problems, and will also
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]1290transparently replace those with chars (i.e. it will not generate entity
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]1291reference elements in the DOM tree or call the reference() SAX callback when
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]1292finding them in the input).</p>
1293
Daniel Veillard7b9c4b72000-08-25 16:26:50 +0000[diff] [blame]1294<p><span style="background-color: #FF0000">WARNING</span>: handling entities
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]1295on top of the libxml SAX interface is difficult!!! If you plan to use
Daniel Veillard7b9c4b72000-08-25 16:26:50 +0000[diff] [blame]1296non-predefined entities in your documents, then the learning cuvre to handle
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]1297then using the SAX API may be long. If you plan to use complex documents, I
Daniel Veillard7b9c4b72000-08-25 16:26:50 +0000[diff] [blame]1298strongly suggest you consider using the DOM interface instead and let libxml
Daniel Veillard8c6d6af2000-08-25 17:14:13 +0000[diff] [blame]1299deal with the complexity rather than trying to do it yourself.</p>
Daniel Veillard7b9c4b72000-08-25 16:26:50 +0000[diff] [blame]1300
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]1301<h2><a name="Namespaces">Namespaces</a></h2>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]1302
Daniel Veillardec303412000-03-24 13:41:54 +0000[diff] [blame]1303<p>The libxml library implements <a
1304href="http://www.w3.org/TR/REC-xml-names/">XML namespaces</a> support by
1305recognizing namespace contructs in the input, and does namespace lookup
1306automatically when building the DOM tree. A namespace declaration is
1307associated with an in-memory structure and all elements or attributes within
1308that namespace point to it. Hence testing the namespace is a simple and fast
1309equality operation at the user level.</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]1310
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]1311<p>I suggest that people using libxml use a namespace, and declare it in the
1312root element of their document as the default namespace. Then they don't need
1313to use the prefix in the content but we will have a basis for future semantic
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]1314refinement and merging of data from different sources. This doesn't increase
Daniel Veillardec70e912001-02-26 20:10:45 +0000[diff] [blame]1315the size of the XML output significantly, but significantly increases its
1316value in the long-term. Example:</p>
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]1317<pre>&lt;mydoc xmlns="http://mydoc.example.org/schemas/"&gt;
1318 &lt;elem1&gt;...&lt;/elem1&gt;
1319 &lt;elem2&gt;...&lt;/elem2&gt;
1320&lt;/mydoc&gt;</pre>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]1321
Daniel Veillardec70e912001-02-26 20:10:45 +0000[diff] [blame]1322<p>The namespace value has to be an absolute URL, but the URL doesn't have to
1323point to any existing resource on the Web. It will bind all the element and
1324atributes with that URL. I suggest to use an URL within a domain you control,
1325and that the URL should contain some kind of version information if possible.
1326For example, <code>"http://www.gnome.org/gnumeric/1.0/"</code> is a good
1327namespace scheme.</p>
Daniel Veillardec303412000-03-24 13:41:54 +0000[diff] [blame]1328
1329<p>Then when you load a file, make sure that a namespace carrying the
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]1330version-independent prefix is installed on the root element of your document,
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]1331and if the version information don't match something you know, warn the user
1332and be liberal in what you accept as the input. Also do *not* try to base
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]1333namespace checking on the prefix value. &lt;foo:text&gt; may be exactly the
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]1334same as &lt;bar:text&gt; in another document. What really matters is the URI
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]1335associated with the element or the attribute, not the prefix string (which is
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]1336just a shortcut for the full URI). In libxml, element and attributes have an
Daniel Veillardec303412000-03-24 13:41:54 +0000[diff] [blame]1337<code>ns</code> field pointing to an xmlNs structure detailing the namespace
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]1338prefix and its URI.</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]1339
1340<p>@@Interfaces@@</p>
1341
1342<p>@@Examples@@</p>
1343
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]1344<p>Usually people object to using namespaces together with validity checking.
1345I will try to make sure that using namespaces won't break validity checking,
1346so even if you plan to use or currently are using validation I strongly
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]1347suggest adding namespaces to your document. A default namespace scheme
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]1348<code>xmlns="http://...."</code> should not break validity even on less
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]1349flexible parsers. Using namespaces to mix and differentiate content coming
Daniel Veillard95189532001-07-26 18:30:26 +0000[diff] [blame]1350from multiple DTDs will certainly break current validation schemes. I will try
1351to provide ways to do this, but this may not be portable or standardized.</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]1352
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]1353<h2><a name="Validation">Validation, or are you afraid of DTDs ?</a></h2>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]1354
1355<p>Well what is validation and what is a DTD ?</p>
1356
1357<p>Validation is the process of checking a document against a set of
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]1358construction rules; a <strong>DTD</strong> (Document Type Definition) is such
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]1359a set of rules.</p>
1360
1361<p>The validation process and building DTDs are the two most difficult parts
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]1362of the XML life cycle. Briefly a DTD defines all the possibles element to be
Daniel Veillard95189532001-07-26 18:30:26 +0000[diff] [blame]1363found within your document, what is the formal shape of your document tree (by
1364defining the allowed content of an element, either text, a regular expression
1365for the allowed list of children, or mixed content i.e. both text and
1366children). The DTD also defines the allowed attributes for all elements and
1367the types of the attributes. For more detailed information, I suggest that you
1368read the related parts of the XML specification, the examples found under
1369gnome-xml/test/valid/dtd and any of the large number of books available on
1370XML. The dia example in gnome-xml/test/valid should be both simple and
Daniel Veillardec70e912001-02-26 20:10:45 +0000[diff] [blame]1371complete enough to allow you to build your own.</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]1372
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]1373<p>A word of warning, building a good DTD which will fit the needs of your
1374application in the long-term is far from trivial; however, the extra level of
Daniel Veillard95189532001-07-26 18:30:26 +0000[diff] [blame]1375quality it can ensure is well worth the price for some sets of applications or
1376if you already have already a DTD defined for your application field.</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]1377
1378<p>The validation is not completely finished but in a (very IMHO) usable
1379state. Until a real validation interface is defined the way to do it is to
Daniel Veillard95189532001-07-26 18:30:26 +0000[diff] [blame]1380define and set the <strong>xmlDoValidityCheckingDefaultValue</strong> external
1381variable to 1, this will of course be changed at some point:</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]1382
1383<p>extern int xmlDoValidityCheckingDefaultValue;</p>
1384
1385<p>...</p>
1386
1387<p>xmlDoValidityCheckingDefaultValue = 1;</p>
1388
1389<p></p>
1390
1391<p>To handle external entities, use the function
1392<strong>xmlSetExternalEntityLoader</strong>(xmlExternalEntityLoader f); to
1393link in you HTTP/FTP/Entities database library to the standard libxml
1394core.</p>
1395
1396<p>@@interfaces@@</p>
1397
Daniel Veillard35008381999-10-25 13:15:52 +0000[diff] [blame]1398<h2><a name="DOM"></a><a name="Principles">DOM Principles</a></h2>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]1399
Daniel Veillard95189532001-07-26 18:30:26 +0000[diff] [blame]1400<p><a href="http://www.w3.org/DOM/">DOM</a> stands for the <em>Document Object
1401Model</em>; this is an API for accessing XML or HTML structured documents.
1402Native support for DOM in Gnome is on the way (module gnome-dom), and will be
1403based on gnome-xml. This will be a far cleaner interface to manipulate XML
1404files within Gnome since it won't expose the internal structure.</p>
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]1405
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]1406<p>The current DOM implementation on top of libxml is the <a
Daniel Veillarda47fb3d2001-03-25 17:23:49 +0000[diff] [blame]1407href="http://cvs.gnome.org/lxr/source/gdome2/">gdome2 Gnome module</a>, this
1408is a full DOM interface, thanks to Paolo Casarini, check the <a
1409href="http://www.cs.unibo.it/~casarini/gdome2/">Gdome2 homepage</a> for more
1410informations.</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]1411
Daniel Veillard35008381999-10-25 13:15:52 +0000[diff] [blame]1412<h2><a name="Example"></a><a name="real">A real example</a></h2>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]1413
1414<p>Here is a real size example, where the actual content of the application
1415data is not kept in the DOM tree but uses internal structures. It is based on
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]1416a proposal to keep a database of jobs related to Gnome, with an XML based
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]1417storage structure. Here is an <a href="gjobs.xml">XML encoded jobs
1418base</a>:</p>
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]1419<pre>&lt;?xml version="1.0"?&gt;
1420&lt;gjob:Helping xmlns:gjob="http://www.gnome.org/some-location"&gt;
1421 &lt;gjob:Jobs&gt;
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]1422
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]1423 &lt;gjob:Job&gt;
1424 &lt;gjob:Project ID="3"/&gt;
1425 &lt;gjob:Application&gt;GBackup&lt;/gjob:Application&gt;
1426 &lt;gjob:Category&gt;Development&lt;/gjob:Category&gt;
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]1427
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]1428 &lt;gjob:Update&gt;
1429 &lt;gjob:Status&gt;Open&lt;/gjob:Status&gt;
1430 &lt;gjob:Modified&gt;Mon, 07 Jun 1999 20:27:45 -0400 MET DST&lt;/gjob:Modified&gt;
1431 &lt;gjob:Salary&gt;USD 0.00&lt;/gjob:Salary&gt;
1432 &lt;/gjob:Update&gt;
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]1433
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]1434 &lt;gjob:Developers&gt;
1435 &lt;gjob:Developer&gt;
1436 &lt;/gjob:Developer&gt;
1437 &lt;/gjob:Developers&gt;
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]1438
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]1439 &lt;gjob:Contact&gt;
1440 &lt;gjob:Person&gt;Nathan Clemons&lt;/gjob:Person&gt;
1441 &lt;gjob:Email&gt;nathan@windsofstorm.net&lt;/gjob:Email&gt;
1442 &lt;gjob:Company&gt;
1443 &lt;/gjob:Company&gt;
1444 &lt;gjob:Organisation&gt;
1445 &lt;/gjob:Organisation&gt;
1446 &lt;gjob:Webpage&gt;
1447 &lt;/gjob:Webpage&gt;
1448 &lt;gjob:Snailmail&gt;
1449 &lt;/gjob:Snailmail&gt;
1450 &lt;gjob:Phone&gt;
1451 &lt;/gjob:Phone&gt;
1452 &lt;/gjob:Contact&gt;
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]1453
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]1454 &lt;gjob:Requirements&gt;
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]1455 The program should be released as free software, under the GPL.
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]1456 &lt;/gjob:Requirements&gt;
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]1457
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]1458 &lt;gjob:Skills&gt;
1459 &lt;/gjob:Skills&gt;
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]1460
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]1461 &lt;gjob:Details&gt;
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]1462 A GNOME based system that will allow a superuser to configure
1463 compressed and uncompressed files and/or file systems to be backed
1464 up with a supported media in the system. This should be able to
1465 perform via find commands generating a list of files that are passed
1466 to tar, dd, cpio, cp, gzip, etc., to be directed to the tape machine
1467 or via operations performed on the filesystem itself. Email
1468 notification and GUI status display very important.
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]1469 &lt;/gjob:Details&gt;
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]1470
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]1471 &lt;/gjob:Job&gt;
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]1472
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]1473 &lt;/gjob:Jobs&gt;
1474&lt;/gjob:Helping&gt;</pre>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]1475
Daniel Veillard95189532001-07-26 18:30:26 +0000[diff] [blame]1476<p>While loading the XML file into an internal DOM tree is a matter of calling
1477only a couple of functions, browsing the tree to gather the ata and generate
1478the internal structures is harder, and more error prone.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]1479
1480<p>The suggested principle is to be tolerant with respect to the input
Daniel Veillard95189532001-07-26 18:30:26 +0000[diff] [blame]1481structure. For example, the ordering of the attributes is not significant, the
1482XML specification is clear about it. It's also usually a good idea not to
Daniel Veillardec70e912001-02-26 20:10:45 +0000[diff] [blame]1483depend on the order of the children of a given node, unless it really makes
1484things harder. Here is some code to parse the information for a person:</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]1485<pre>/*
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]1486 * A person record
1487 */
1488typedef struct person {
1489 char *name;
1490 char *email;
1491 char *company;
1492 char *organisation;
1493 char *smail;
1494 char *webPage;
1495 char *phone;
1496} person, *personPtr;
1497
1498/*
1499 * And the code needed to parse it
1500 */
1501personPtr parsePerson(xmlDocPtr doc, xmlNsPtr ns, xmlNodePtr cur) {
1502 personPtr ret = NULL;
1503
1504DEBUG("parsePerson\n");
1505 /*
1506 * allocate the struct
1507 */
1508 ret = (personPtr) malloc(sizeof(person));
1509 if (ret == NULL) {
1510 fprintf(stderr,"out of memory\n");
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]1511 return(NULL);
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]1512 }
1513 memset(ret, 0, sizeof(person));
1514
1515 /* We don't care what the top level element name is */
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]1516 cur = cur-&gt;xmlChildrenNode;
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]1517 while (cur != NULL) {
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]1518 if ((!strcmp(cur-&gt;name, "Person")) &amp;&amp; (cur-&gt;ns == ns))
1519 ret-&gt;name = xmlNodeListGetString(doc, cur-&gt;xmlChildrenNode, 1);
1520 if ((!strcmp(cur-&gt;name, "Email")) &amp;&amp; (cur-&gt;ns == ns))
1521 ret-&gt;email = xmlNodeListGetString(doc, cur-&gt;xmlChildrenNode, 1);
1522 cur = cur-&gt;next;
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]1523 }
1524
1525 return(ret);
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]1526}</pre>
1527
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]1528<p>Here are a couple of things to notice:</p>
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]1529<ul>
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]1530 <li>Usually a recursive parsing style is the more convenient one: XML data
1531 is by nature subject to repetitive constructs and usually exibits highly
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]1532 stuctured patterns.</li>
Daniel Veillard95189532001-07-26 18:30:26 +0000[diff] [blame]1533 <li>The two arguments of type <em>xmlDocPtr</em> and <em>xmlNsPtr</em>, i.e.
1534 the pointer to the global XML document and the namespace reserved to the
1535 application. Document wide information are needed for example to decode
1536 entities and it's a good coding practice to define a namespace for your
1537 application set of data and test that the element and attributes you're
1538 analyzing actually pertains to your application space. This is done by a
1539 simple equality test (cur-&gt;ns == ns).</li>
Daniel Veillardec70e912001-02-26 20:10:45 +0000[diff] [blame]1540 <li>To retrieve text and attributes value, you can use the function
1541 <em>xmlNodeListGetString</em> to gather all the text and entity reference
1542 nodes generated by the DOM output and produce an single text string.</li>
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]1543</ul>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]1544
1545<p>Here is another piece of code used to parse another level of the
1546structure:</p>
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]1547<pre>#include &lt;libxml/tree.h&gt;
Daniel Veillard361d8452000-04-03 19:48:13 +0000[diff] [blame]1548/*
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]1549 * a Description for a Job
1550 */
1551typedef struct job {
1552 char *projectID;
1553 char *application;
1554 char *category;
1555 personPtr contact;
1556 int nbDevelopers;
1557 personPtr developers[100]; /* using dynamic alloc is left as an exercise */
1558} job, *jobPtr;
1559
1560/*
1561 * And the code needed to parse it
1562 */
1563jobPtr parseJob(xmlDocPtr doc, xmlNsPtr ns, xmlNodePtr cur) {
1564 jobPtr ret = NULL;
1565
1566DEBUG("parseJob\n");
1567 /*
1568 * allocate the struct
1569 */
1570 ret = (jobPtr) malloc(sizeof(job));
1571 if (ret == NULL) {
1572 fprintf(stderr,"out of memory\n");
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]1573 return(NULL);
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]1574 }
1575 memset(ret, 0, sizeof(job));
1576
1577 /* We don't care what the top level element name is */
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]1578 cur = cur-&gt;xmlChildrenNode;
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]1579 while (cur != NULL) {
1580
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]1581 if ((!strcmp(cur-&gt;name, "Project")) &amp;&amp; (cur-&gt;ns == ns)) {
1582 ret-&gt;projectID = xmlGetProp(cur, "ID");
1583 if (ret-&gt;projectID == NULL) {
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]1584 fprintf(stderr, "Project has no ID\n");
1585 }
1586 }
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]1587 if ((!strcmp(cur-&gt;name, "Application")) &amp;&amp; (cur-&gt;ns == ns))
1588 ret-&gt;application = xmlNodeListGetString(doc, cur-&gt;xmlChildrenNode, 1);
1589 if ((!strcmp(cur-&gt;name, "Category")) &amp;&amp; (cur-&gt;ns == ns))
1590 ret-&gt;category = xmlNodeListGetString(doc, cur-&gt;xmlChildrenNode, 1);
1591 if ((!strcmp(cur-&gt;name, "Contact")) &amp;&amp; (cur-&gt;ns == ns))
1592 ret-&gt;contact = parsePerson(doc, ns, cur);
1593 cur = cur-&gt;next;
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]1594 }
1595
1596 return(ret);
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]1597}</pre>
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]1598
Daniel Veillardec70e912001-02-26 20:10:45 +0000[diff] [blame]1599<p>Once you are used to it, writing this kind of code is quite simple, but
Daniel Veillard95189532001-07-26 18:30:26 +0000[diff] [blame]1600boring. Ultimately, it could be possble to write stubbers taking either C data
1601structure definitions, a set of XML examples or an XML DTD and produce the
1602code needed to import and export the content between C data and XML storage.
1603This is left as an exercise to the reader :-)</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]1604
Daniel Veillard6f0adb52000-07-03 11:41:26 +0000[diff] [blame]1605<p>Feel free to use <a href="example/gjobread.c">the code for the full C
1606parsing example</a> as a template, it is also available with Makefile in the
1607Gnome CVS base under gnome-xml/example</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]1608
Daniel Veillardc310d562000-06-23 18:32:15 +0000[diff] [blame]1609<h2><a name="Contributi">Contributions</a></h2>
1610<ul>
Daniel Veillard95189532001-07-26 18:30:26 +0000[diff] [blame]1611 <li><a href="mailto:ari@lusis.org">Ari Johnson</a> provides a C++ wrapper
1612 for libxml:
Daniel Veillardc310d562000-06-23 18:32:15 +0000[diff] [blame]1613 <p>Website: <a
1614 href="http://lusis.org/~ari/xml++/">http://lusis.org/~ari/xml++/</a></p>
1615 <p>Download: <a
1616 href="http://lusis.org/~ari/xml++/libxml++.tar.gz">http://lusis.org/~ari/xml++/libxml++.tar.gz</a></p>
1617 </li>
Daniel Veillard95189532001-07-26 18:30:26 +0000[diff] [blame]1618 <li><a href="mailto:izlatkovic@daenet.de">Igor Zlatkovic</a> is now the
1619 maintainer of the Windows port, <a
1620 href="http://www.fh-frankfurt.de/~igor/projects/libxml/index.html">he
1621 provides binaries</a></li>
Daniel Veillarde356c282001-03-10 12:32:04 +0000[diff] [blame]1622 <li><a
1623 href="http://mail.gnome.org/archives/xml/2001-March/msg00014.html">Matt
Daniel Veillard95189532001-07-26 18:30:26 +0000[diff] [blame]1624 Sergeant</a> developped <a
1625 href="http://axkit.org/download/">XML::LibXSLT</a>, a perl wrapper for
1626 libxml2/libxslt as part of the <a href="http://axkit.com/">AxKit XML
1627 application server</a></li>
1628 <li><a href="mailto:fnatter@gmx.net">Felix Natter</a> and <a
1629 href="mailto:geertk@ai.rug.nl">Geert Kloosterman</a> provide <a
Daniel Veillardca989762001-06-23 17:39:29 +0000[diff] [blame]1630 href="libxml-doc.el">an emacs module</a> to lookup libxml(2) functions
Daniel Veillard3f6f7f62000-06-30 17:58:25 +0000[diff] [blame]1631 documentation</li>
Daniel Veillard95189532001-07-26 18:30:26 +0000[diff] [blame]1632 <li><a href="mailto:sherwin@nlm.nih.gov">Ziying Sherwin</a> provided <a
1633 href="http://xmlsoft.org/messages/0488.html">man pages</a></li>
Daniel Veillard5168dbf2001-07-07 00:18:23 +0000[diff] [blame]1634 <li>there is a module for <a
1635 href="http://acs-misc.sourceforge.net/nsxml.html">libxml/libxslt support
1636 in OpenNSD/AOLServer</a></li>
Daniel Veillard25997ca2001-07-27 18:56:57 +0000[diff] [blame]1637 <li><a href="mailto:dkuhlman@cutter.rexx.com">Dave Kuhlman</a> provides
1638 libxml/libxslt <a href="http://www.rexx.com/~dkuhlman">wrappers for
1639 Python</a></li>
Daniel Veillardc310d562000-06-23 18:32:15 +0000[diff] [blame]1640</ul>
1641
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]1642<p></p>
1643
Daniel Veillard33a67802001-03-07 09:44:02 +0000[diff] [blame]1644<p><a href="mailto:Daniel.Veillard@imag.fr">Daniel Veillard</a></p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]1645
Daniel Veillard25997ca2001-07-27 18:56:57 +0000[diff] [blame]1646<p>$Id: xml.html,v 1.103 2001/07/26 18:30:26 veillard Exp $</p>
Daniel Veillardccb09631998-10-27 06:21:04 +0000[diff] [blame]1647</body>
1648</html>