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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 Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]6 <meta name="GENERATOR" content="amaya V5.0">
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 Veillardec78c0f2000-08-25 10:25:23 +0000[diff] [blame]11<h1 align="center">The XML C library for Gnome</h1>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]12
Daniel Veillard9c466822001-10-25 12:03:39 +0000[diff] [blame]13<h1>Note: this is the flat content of the <a href="index.html">web
14site</a></h1>
15
Daniel Veillardc9484202001-10-24 12:35:52 +0000[diff] [blame]16<h1 style="text-align: center">libxml, a.k.a. gnome-xml</h1>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]17
18<p></p>
Daniel Veillard9c466822001-10-25 12:03:39 +0000[diff] [blame]19
20<p>Libxml is the XML C library developped for the Gnome project. XML itself
21is a metalanguage to design markup languages, i.e. text language where
22semantic and structure are added to the content using extra "markup"
23information enclosed between angle bracket. HTML is the most well-known
24markup language.</p>
25
26<p>Libxml2 implements a number of existing standards related to markup
27languages:</p>
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]28<ul>
Daniel Veillard9c466822001-10-25 12:03:39 +0000[diff] [blame]29 <li>the XML standard: <a
30 href="http://www.w3.org/TR/REC-xml">http://www.w3.org/TR/REC-xml</a></li>
31 <li>Namespaces in XML: <a
32 href="http://www.w3.org/TR/REC-xml-names/">http://www.w3.org/TR/REC-xml-names/</a></li>
33 <li>XML Base: <a
34 href="http://www.w3.org/TR/xmlbase/">http://www.w3.org/TR/xmlbase/</a></li>
35 <li><a href="http://www.cis.ohio-state.edu/rfc/rfc2396.txt">RFC 2396</a>
Daniel Veillardc6271d22001-10-27 07:50:58 +0000[diff] [blame]36 : Uniform Resource Identifiers <a
Daniel Veillard9c466822001-10-25 12:03:39 +0000[diff] [blame]37 href="http://www.ietf.org/rfc/rfc2396.txt">http://www.ietf.org/rfc/rfc2396.txt</a></li>
38 <li>XML Path Language (XPath) 1.0: <a
39 href="http://www.w3.org/TR/xpath">http://www.w3.org/TR/xpath</a></li>
40 <li>HTML4 parser: <a
41 href="http://www.w3.org/TR/html401/">http://www.w3.org/TR/html401/</a></li>
42 <li>most of XML Pointer Language (XPointer) Version 1.0: <a
43 href="http://www.w3.org/TR/xptr">http://www.w3.org/TR/xptr</a></li>
44 <li>XML Inclusions (XInclude) Version 1.0: <a
45 href="http://www.w3.org/TR/xinclude/">http://www.w3.org/TR/xinclude/</a></li>
46 <li>[ISO-8859-1], <a
47 href="http://www.cis.ohio-state.edu/rfc/rfc2044.txt">rfc2044</a> [UTF-8]
48 and <a href="http://www.cis.ohio-state.edu/rfc/rfc2781.txt">rfc2781</a>
49 [UTF-16] core encodings</li>
50 <li>part of SGML Open Technical Resolution TR9401:1997</li>
51 <li>XML Catalogs Working Draft 06 August 2001: <a
52 href="http://www.oasis-open.org/committees/entity/spec-2001-08-06.html">http://www.oasis-open.org/committees/entity/spec-2001-08-06.html</a></li>
Daniel Veillard96984452000-08-31 13:50:12 +0000[diff] [blame]53</ul>
54
Daniel Veillard9c466822001-10-25 12:03:39 +0000[diff] [blame]55<p>In most cases libxml tries to implement the specifications in a relatively
56strict way. To some extent libxml2 provide some support for the following
57other specification but don't claim to implement them:</p>
58<ul>
59 <li>Document Object Model (DOM) <a
60 href="http://www.w3.org/TR/DOM-Level-2-Core/">http://www.w3.org/TR/DOM-Level-2-Core/</a>
61 it doesn't implement the API itself, gdome2 does this in top of
62 libxml2</li>
63 <li><a href="http://www.cis.ohio-state.edu/rfc/rfc959.txt">RFC 959</a>
Daniel Veillardc6271d22001-10-27 07:50:58 +0000[diff] [blame]64 : libxml implements a basic FTP client code</li>
Daniel Veillard9c466822001-10-25 12:03:39 +0000[diff] [blame]65 <li><a href="http://www.cis.ohio-state.edu/rfc/rfc1945.txt">RFC 1945</a>
Daniel Veillardc6271d22001-10-27 07:50:58 +0000[diff] [blame]66 : HTTP/1.0, again a basic HTTP client code</li>
Daniel Veillard9c466822001-10-25 12:03:39 +0000[diff] [blame]67 <li>SAX: a minimal SAX implementation compatible with early expat
68 versions</li>
69 <li>DocBook SGML v4: libxml2 includes a hackish parser to transition to
70 XML</li>
71</ul>
72
Daniel Veillard845cce42002-01-09 11:51:37 +0000[diff] [blame]73<p>Libxml2 is known to be very portable, should build and work without
74serious troubles on a variety of systems (Linux, Unix, Windows, CygWin,
75MacOs, MacOsX, RISC Os, OS/2, VMS, QNX, MVS, ...)</p>
Daniel Veillard9c466822001-10-25 12:03:39 +0000[diff] [blame]76
Daniel Veillard96984452000-08-31 13:50:12 +0000[diff] [blame]77<p>Separate documents:</p>
78<ul>
Daniel Veillardc6271d22001-10-27 07:50:58 +0000[diff] [blame]79 <li><a href="http://xmlsoft.org/XSLT/">the libxslt page</a>
80 providing an implementation of XSLT 1.0 and extensions on top of
81 libxml2</li>
82 <li><a href="http://www.cs.unibo.it/~casarini/gdome2/">the gdome2 page</a>
Daniel Veillard51095312001-10-28 18:51:57 +0000[diff] [blame]83 : a standard DOM2 implementation based on libxml2</li>
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]84</ul>
85
86<h2><a name="Introducti">Introduction</a></h2>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]87
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]88<p>This document describes libxml, the <a
Daniel Veillardec78c0f2000-08-25 10:25:23 +0000[diff] [blame]89href="http://www.w3.org/XML/">XML</a> C library developped for the <a
90href="http://www.gnome.org/">Gnome</a> project. <a
91href="http://www.w3.org/XML/">XML is a standard</a> for building tag-based
92structured documents/data.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]93
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]94<p>Here are some key points about libxml:</p>
95<ul>
Daniel Veillard189446d2000-10-13 10:23:06 +0000[diff] [blame]96 <li>Libxml exports Push and Pull type parser interfaces for both XML and
97 HTML.</li>
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]98 <li>Libxml can do DTD validation at parse time, using a parsed document
99 instance, or with an arbitrary DTD.</li>
100 <li>Libxml now includes nearly complete <a
Daniel Veillard8c2ecaf2001-07-10 17:53:07 +0000[diff] [blame]101 href="http://www.w3.org/TR/xpath">XPath</a>, <a
102 href="http://www.w3.org/TR/xptr">XPointer</a> and <a
103 href="http://www.w3.org/TR/xinclude">XInclude</a> implementations.</li>
Daniel Veillardec78c0f2000-08-25 10:25:23 +0000[diff] [blame]104 <li>It is written in plain C, making as few assumptions as possible, and
Daniel Veillard189446d2000-10-13 10:23:06 +0000[diff] [blame]105 sticking closely to ANSI C/POSIX for easy embedding. Works on
Daniel Veillardab8500d2000-10-15 21:06:19 +0000[diff] [blame]106 Linux/Unix/Windows, ported to a number of other platforms.</li>
Daniel Veillardec70e912001-02-26 20:10:45 +0000[diff] [blame]107 <li>Basic support for HTTP and FTP client allowing aplications to fetch
108 remote resources</li>
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]109 <li>The design is modular, most of the extensions can be compiled out.</li>
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]110 <li>The internal document repesentation is as close as possible to the <a
111 href="http://www.w3.org/DOM/">DOM</a> interfaces.</li>
112 <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]113 like interface</a>; the interface is designed to be compatible with <a
114 href="http://www.jclark.com/xml/expat.html">Expat</a>.</li>
Daniel Veillardc575b992002-02-08 13:28:40 +0000[diff] [blame]115 <li>This library is released under the <a
116 href="http://www.opensource.org/licenses/mit-license.html">MIT
117 Licence</a> see the Copyright file in the distribution for the precise
118 wording.</li>
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]119</ul>
Daniel Veillardccb09631998-10-27 06:21:04 +0000[diff] [blame]120
Daniel Veillarde0c1d722001-03-21 10:28:36 +0000[diff] [blame]121<p>Warning: unless you are forced to because your application links with a
122Gnome library requiring it, <strong><span
123style="background-color: #FF0000">Do Not Use libxml1</span></strong>, use
124libxml2</p>
125
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]126<h2><a name="FAQ">FAQ</a></h2>
127
128<p>Table of Content:</p>
129<ul>
130 <li><a href="FAQ.html#Licence">Licence(s)</a></li>
131 <li><a href="FAQ.html#Installati">Installation</a></li>
132 <li><a href="FAQ.html#Compilatio">Compilation</a></li>
133 <li><a href="FAQ.html#Developer">Developer corner</a></li>
134</ul>
135
136<h3><a name="Licence">Licence</a>(s)</h3>
137<ol>
138 <li><em>Licensing Terms for libxml</em>
Daniel Veillardc575b992002-02-08 13:28:40 +0000[diff] [blame]139 <p>libxml is released under the <a
140 href="http://www.opensource.org/licenses/mit-license.html">MIT
141 Licence</a>, see the file Copyright in the distribution for the precise
142 wording</p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]143 </li>
144 <li><em>Can I embed libxml in a proprietary application ?</em>
Daniel Veillardc575b992002-02-08 13:28:40 +0000[diff] [blame]145 <p>Yes. The MIT Licence allows you to also keep proprietary the changes
146 you made to libxml, but it would be graceful to provide back bugfixes and
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]147 improvements as patches for possible incorporation in the main
148 development tree</p>
149 </li>
150</ol>
151
152<h3><a name="Installati">Installation</a></h3>
153<ol>
154 <li>Unless you are forced to because your application links with a Gnome
155 library requiring it, <strong><span style="background-color: #FF0000">Do
156 Not Use libxml1</span></strong>, use libxml2</li>
157 <li><em>Where can I get libxml</em>
158 ?
159 <p>The original distribution comes from <a
160 href="ftp://rpmfind.net/pub/libxml/">rpmfind.net</a> or <a
161 href="ftp://ftp.gnome.org/pub/GNOME/stable/sources/libxml/">gnome.org</a></p>
162 <p>Most linux and Bsd distribution includes libxml, this is probably the
163 safer way for end-users</p>
164 <p>David Doolin provides precompiled Windows versions at <a
165 href="http://www.ce.berkeley.edu/~doolin/code/libxmlwin32/ ">http://www.ce.berkeley.edu/~doolin/code/libxmlwin32/</a></p>
166 </li>
167 <li><em>I see libxml and libxml2 releases, which one should I install ?</em>
168 <ul>
169 <li>If you are not concerned by any existing backward compatibility
170 with existing application, install libxml2 only</li>
171 <li>If you are not doing development, you can safely install both.
172 usually the packages <a
173 href="http://rpmfind.net/linux/RPM/libxml.html">libxml</a> and <a
174 href="http://rpmfind.net/linux/RPM/libxml2.html">libxml2</a> are
175 compatible (this is not the case for development packages)</li>
176 <li>If you are a developer and your system provides separate packaging
177 for shared libraries and the development components, it is possible
178 to install libxml and libxml2, and also <a
179 href="http://rpmfind.net/linux/RPM/libxml-devel.html">libxml-devel</a>
180 and <a
181 href="http://rpmfind.net/linux/RPM/libxml2-devel.html">libxml2-devel</a>
182 too for libxml2 &gt;= 2.3.0</li>
183 <li>If you are developing a new application, please develop against
184 libxml2(-devel)</li>
185 </ul>
186 </li>
187 <li><em>I can't install the libxml package it conflicts with libxml0</em>
188 <p>You probably have an old libxml0 package used to provide the shared
189 library for libxml.so.0, you can probably safely remove it. Anyway the
190 libxml packages provided on <a
191 href="ftp://rpmfind.net/pub/libxml/">rpmfind.net</a> provides
192 libxml.so.0</p>
193 </li>
194 <li><em>I can't install the libxml(2) RPM package due to failed
195 dependancies</em>
196 <p>The most generic solution is to refetch the latest src.rpm , and
197 rebuild it locally with</p>
198 <p><code>rpm --rebuild libxml(2)-xxx.src.rpm</code></p>
199 <p>if everything goes well it will generate two binary rpm (one providing
200 the shared libs and xmllint, and the other one, the -devel package
201 providing includes, static libraries and scripts needed to build
202 applications with libxml(2)) that you can install locally.</p>
203 </li>
204</ol>
205
206<h3><a name="Compilatio">Compilation</a></h3>
207<ol>
208 <li><em>What is the process to compile libxml ?</em>
209 <p>As most UNIX libraries libxml follows the "standard":</p>
210 <p><code>gunzip -c xxx.tar.gz | tar xvf -</code></p>
211 <p><code>cd libxml-xxxx</code></p>
212 <p><code>./configure --help</code></p>
213 <p>to see the options, then the compilation/installation proper</p>
214 <p><code>./configure [possible options]</code></p>
215 <p><code>make</code></p>
216 <p><code>make install</code></p>
217 <p>At that point you may have to rerun ldconfig or similar utility to
218 update your list of installed shared libs.</p>
219 </li>
220 <li><em>What other libraries are needed to compile/install libxml ?</em>
221 <p>Libxml does not requires any other library, the normal C ANSI API
222 should be sufficient (please report any violation to this rule you may
223 find).</p>
224 <p>However if found at configuration time libxml will detect and use the
225 following libs:</p>
226 <ul>
227 <li><a href="http://www.info-zip.org/pub/infozip/zlib/">libz</a>
228 : a highly portable and available widely compression library</li>
229 <li>iconv: a powerful character encoding conversion library. It's
230 included by default on recent glibc libraries, so it doesn't need to
231 be installed specifically on linux. It seems it's now <a
232 href="http://www.opennc.org/onlinepubs/7908799/xsh/iconv.html">part
233 of the official UNIX</a> specification. Here is one <a
234 href="http://clisp.cons.org/~haible/packages-libiconv.html">implementation
235 of the library</a> which source can be found <a
236 href="ftp://ftp.ilog.fr/pub/Users/haible/gnu/">here</a>.</li>
237 </ul>
238 </li>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]239 <li><em>make check fails on some platforms</em>
240 <p>Sometime the regression tests results don't completely match the value
241 produced by the parser, and the makefile uses diff to print the delta. On
242 some platforms the diff return breaks the compilation process, if the
Daniel Veillarde46182c2002-02-12 14:29:11 +0000[diff] [blame]243 diff is small this is probably not a serious problem.</p>
244 <p>Sometimes (especially on Solaris) make checks fails due to limitations
245 in make. Try using GNU-make instead.</p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]246 </li>
247 <li><em>I use the CVS version and there is no configure script</em>
248 <p>The configure (and other Makefiles) are generated. Use the autogen.sh
249 script to regenerate the configure and Makefiles, like:</p>
250 <p><code>./autogen.sh --prefix=/usr --disable-shared</code></p>
251 </li>
252 <li><em>I have troubles when running make tests with gcc-3.0</em>
253 <p>It seems the initial release of gcc-3.0 has a problem with the
254 optimizer which miscompiles the URI module. Please use another
255 compiler</p>
256 </li>
257</ol>
258
259<h3><a name="Developer">Developer</a> corner</h3>
260<ol>
261 <li><em>xmlDocDump() generates output on one line</em>
262 <p>libxml will not <strong>invent</strong> spaces in the content of a
263 document since <strong>all spaces in the content of a document are
264 significant</strong>. If you build a tree from the API and want
265 indentation:</p>
266 <ol>
267 <li>the correct way is to generate those yourself too</li>
268 <li>the dangerous way is to ask libxml to add those blanks to your
269 content <strong>modifying the content of your document in the
270 process</strong>. The result may not be what you expect. There is
271 <strong>NO</strong> way to guarantee that such a modification won't
272 impact other part of the content of your document. See <a
273 href="http://xmlsoft.org/html/libxml-parser.html#XMLKEEPBLANKSDEFAULT">xmlKeepBlanksDefault
274 ()</a> and <a
275 href="http://xmlsoft.org/html/libxml-tree.html#XMLSAVEFORMATFILE">xmlSaveFormatFile
276 ()</a></li>
277 </ol>
278 </li>
279 <li>Extra nodes in the document:
280 <p><em>For a XML file as below:</em></p>
281 <pre>&lt;?xml version="1.0"?&gt;
282&lt;PLAN xmlns="http://www.argus.ca/autotest/1.0/"&gt;
283&lt;NODE CommFlag="0"/&gt;
284&lt;NODE CommFlag="1"/&gt;
285&lt;/PLAN&gt;</pre>
286 <p><em>after parsing it with the function
287 pxmlDoc=xmlParseFile(...);</em></p>
288 <p><em>I want to the get the content of the first node (node with the
289 CommFlag="0")</em></p>
290 <p><em>so I did it as following;</em></p>
291 <pre>xmlNodePtr pode;
292pnode=pxmlDoc-&gt;children-&gt;children;</pre>
293 <p><em>but it does not work. If I change it to</em></p>
294 <pre>pnode=pxmlDoc-&gt;children-&gt;children-&gt;next;</pre>
295 <p><em>then it works. Can someone explain it to me.</em></p>
296 <p></p>
297 <p>In XML all characters in the content of the document are significant
298 <strong>including blanks and formatting line breaks</strong>.</p>
299 <p>The extra nodes you are wondering about are just that, text nodes with
300 the formatting spaces wich are part of the document but that people tend
301 to forget. There is a function <a
302 href="http://xmlsoft.org/html/libxml-parser.html">xmlKeepBlanksDefault
303 ()</a> to remove those at parse time, but that's an heuristic, and its
304 use should be limited to case where you are sure there is no
305 mixed-content in the document.</p>
306 </li>
307 <li><em>I get compilation errors of existing code like when accessing
308 <strong>root</strong> or <strong>childs fields</strong> of nodes</em>
309 <p>You are compiling code developed for libxml version 1 and using a
310 libxml2 development environment. Either switch back to libxml v1 devel or
311 even better fix the code to compile with libxml2 (or both) by <a
312 href="upgrade.html">following the instructions</a>.</p>
313 </li>
314 <li><em>I get compilation errors about non existing
315 <strong>xmlRootNode</strong> or <strong>xmlChildrenNode</strong>
316 fields</em>
317 <p>The source code you are using has been <a
318 href="upgrade.html">upgraded</a> to be able to compile with both libxml
319 and libxml2, but you need to install a more recent version:
320 libxml(-devel) &gt;= 1.8.8 or libxml2(-devel) &gt;= 2.1.0</p>
321 </li>
322 <li><em>XPath implementation looks seriously broken</em>
323 <p>XPath implementation prior to 2.3.0 was really incomplete, upgrade to
324 a recent version, the implementation and debug of libxslt generated fixes
325 for most obvious problems.</p>
326 </li>
327 <li><em>The example provided in the web page does not compile</em>
328 <p>It's hard to maintain the documentation in sync with the code
329 &lt;grin/&gt; ...</p>
330 <p>Check the previous points 1/ and 2/ raised before, and send
331 patches.</p>
332 </li>
333 <li><em>Where can I get more examples and informations than in the web
334 page</em>
335 <p>Ideally a libxml book would be nice. I have no such plan ... But you
336 can:</p>
337 <ul>
338 <li>check more deeply the <a href="html/libxml-lib.html">existing
339 generated doc</a></li>
340 <li>looks for examples of use for libxml function using the Gnome code
341 for example the following will query the full Gnome CVs base for the
342 use of the <strong>xmlAddChild()</strong> function:
343 <p><a
344 href="http://cvs.gnome.org/lxr/search?string=xmlAddChild">http://cvs.gnome.org/lxr/search?string=xmlAddChild</a></p>
345 <p>This may be slow, a large hardware donation to the gnome project
346 could cure this :-)</p>
347 </li>
348 <li><a
349 href="http://cvs.gnome.org/bonsai/rview.cgi?cvsroot=/cvs/gnome&amp;dir=gnome-xml">Browse
350 the libxml source</a>
351 , I try to write code as clean and documented as possible, so
352 looking at it may be helpful</li>
353 </ul>
354 </li>
355 <li>What about C++ ?
356 <p>libxml is written in pure C in order to allow easy reuse on a number
357 of platforms, including embedded systems. I don't intend to convert to
358 C++.</p>
359 <p>There is however a C++ wrapper provided by Ari Johnson
360 &lt;ari@btigate.com&gt; which may fullfill your needs:</p>
361 <p>Website: <a
362 href="http://lusis.org/~ari/xml++/">http://lusis.org/~ari/xml++/</a></p>
363 <p>Download: <a
364 href="http://lusis.org/~ari/xml++/libxml++.tar.gz">http://lusis.org/~ari/xml++/libxml++.tar.gz</a></p>
365 </li>
366 <li>How to validate a document a posteriori ?
367 <p>It is possible to validate documents which had not been validated at
368 initial parsing time or documents who have been built from scratch using
369 the API. Use the <a
370 href="http://xmlsoft.org/html/libxml-valid.html#XMLVALIDATEDTD">xmlValidateDtd()</a>
371 function. It is also possible to simply add a Dtd to an existing
372 document:</p>
373 <pre>xmlDocPtr doc; /* your existing document */
374 xmlDtdPtr dtd = xmlParseDTD(NULL, filename_of_dtd); /* parse the DTD */
375 dtd-&gt;name = xmlStrDup((xmlChar*)"root_name"); /* use the given root */
376
377 doc-&gt;intSubset = dtd;
378 if (doc-&gt;children == NULL) xmlAddChild((xmlNodePtr)doc, (xmlNodePtr)dtd);
379 else xmlAddPrevSibling(doc-&gt;children, (xmlNodePtr)dtd);
380 </pre>
381 </li>
382 <li>etc ...</li>
383</ol>
384
385<p></p>
386
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]387<h2><a name="Documentat">Documentation</a></h2>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]388
Daniel Veillard402e8c82000-02-29 22:57:47 +0000[diff] [blame]389<p>There are some on-line resources about using libxml:</p>
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]390<ol>
Daniel Veillard365e13b2000-07-02 07:56:37 +0000[diff] [blame]391 <li>Check the <a href="FAQ.html">FAQ</a></li>
Daniel Veillardc19fccc2000-07-03 11:52:01 +0000[diff] [blame]392 <li>Check the <a href="http://xmlsoft.org/html/libxml-lib.html">extensive
Daniel Veillard8c6d6af2000-08-25 17:14:13 +0000[diff] [blame]393 documentation</a> automatically extracted from code comments (using <a
394 href="http://cvs.gnome.org/bonsai/rview.cgi?cvsroot=/cvs/gnome&amp;dir=gtk-doc">gtk
395 doc</a>).</li>
Daniel Veillard8d869642000-07-14 12:12:59 +0000[diff] [blame]396 <li>Look at the documentation about <a href="encoding.html">libxml
397 internationalization support</a></li>
Daniel Veillardbc66f852002-01-14 09:49:20 +0000[diff] [blame]398 <li>This page provides a global overview and <a href="example.html">some
Daniel Veillard402e8c82000-02-29 22:57:47 +0000[diff] [blame]399 examples</a> on how to use libxml.</li>
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]400 <li><a href="mailto:james@daa.com.au">James Henstridge</a>
401 wrote <a
Daniel Veillard402e8c82000-02-29 22:57:47 +0000[diff] [blame]402 href="http://www.daa.com.au/~james/gnome/xml-sax/xml-sax.html">some nice
403 documentation</a> explaining how to use the libxml SAX interface.</li>
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]404 <li>George Lebl wrote <a
405 href="http://www-4.ibm.com/software/developer/library/gnome3/">an article
Daniel Veillard402e8c82000-02-29 22:57:47 +0000[diff] [blame]406 for IBM developerWorks</a> about using libxml.</li>
Daniel Veillardec303412000-03-24 13:41:54 +0000[diff] [blame]407 <li>Check <a href="http://cvs.gnome.org/lxr/source/gnome-xml/TODO">the TODO
408 file</a></li>
409 <li>Read the <a href="upgrade.html">1.x to 2.x upgrade path</a>. If you are
410 starting a new project using libxml you should really use the 2.x
411 version.</li>
Daniel Veillard845cce42002-01-09 11:51:37 +0000[diff] [blame]412 <li>And don't forget to look at the <a
413 href="http://mail.gnome.org/archives/xml/">mailing-list archive</a>.</li>
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]414</ol>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]415
Daniel Veillardd5f97f82000-09-17 16:38:14 +0000[diff] [blame]416<h2><a name="Reporting">Reporting bugs and getting help</a></h2>
Daniel Veillard4c3a2031999-11-19 17:46:26 +0000[diff] [blame]417
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]418<p>Well, bugs or missing features are always possible, and I will make a
419point of fixing them in a timely fashion. The best way to report a bug is to
420use the <a href="http://bugzilla.gnome.org/buglist.cgi?product=libxml">Gnome
421bug tracking database</a> (make sure to use the "libxml" module name). I look
422at reports there regularly and it's good to have a reminder when a bug is
Daniel Veillard51095312001-10-28 18:51:57 +0000[diff] [blame]423still open. Be sure to specify that the bug is for the package libxml.</p>
Daniel Veillard4c3a2031999-11-19 17:46:26 +0000[diff] [blame]424
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]425<p>There is also a mailing-list <a
Daniel Veillard3197f162001-04-04 00:40:08 +0000[diff] [blame]426href="mailto:xml@gnome.org">xml@gnome.org</a> for libxml, with an <a
427href="http://mail.gnome.org/archives/xml/">on-line archive</a> (<a
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]428href="http://xmlsoft.org/messages">old</a>). To subscribe to this list,
429please visit the <a
430href="http://mail.gnome.org/mailman/listinfo/xml">associated Web</a> page and
431follow the instructions. <strong>Do not send code, I won't debug it</strong>
432(but patches are really appreciated!).</p>
Daniel Veillard234547b2001-07-05 09:46:10 +0000[diff] [blame]433
Daniel Veillard008186f2001-09-13 14:24:44 +0000[diff] [blame]434<p>Check the following <strong><span style="color: #FF0000">before
435posting</span></strong>:</p>
Daniel Veillard234547b2001-07-05 09:46:10 +0000[diff] [blame]436<ul>
Daniel Veillarddadd0872001-09-15 09:21:44 +0000[diff] [blame]437 <li>read the <a href="FAQ.html">FAQ</a></li>
Daniel Veillard234547b2001-07-05 09:46:10 +0000[diff] [blame]438 <li>make sure you are <a href="ftp://xmlsoft.org/">using a recent
439 version</a>, and that the problem still shows up in those</li>
440 <li>check the <a href="http://mail.gnome.org/archives/xml/">list
441 archives</a> to see if the problem was reported already, in this case
Daniel Veillarde7ead2d2001-08-22 23:44:09 +0000[diff] [blame]442 there is probably a fix available, similary check the <a
443 href="http://bugzilla.gnome.org/buglist.cgi?product=libxml">registered
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]444 open bugs</a></li>
Daniel Veillard234547b2001-07-05 09:46:10 +0000[diff] [blame]445 <li>make sure you can reproduce the bug with xmllint or one of the test
446 programs found in source in the distribution</li>
447 <li>Please send the command showing the error as well as the input (as an
448 attachement)</li>
449</ul>
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]450
Daniel Veillarddadd0872001-09-15 09:21:44 +0000[diff] [blame]451<p>Then send the bug with associated informations to reproduce it to the <a
Daniel Veillard33a67802001-03-07 09:44:02 +0000[diff] [blame]452href="mailto:xml@gnome.org">xml@gnome.org</a> list; if it's really libxml
Daniel Veillard008186f2001-09-13 14:24:44 +0000[diff] [blame]453related I will approve it.. Please do not send me mail directly, it makes
454things really harder to track and in some cases I'm not the best person to
455answer a given question, ask the list instead.</p>
Daniel Veillard4c3a2031999-11-19 17:46:26 +0000[diff] [blame]456
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]457<p>Of course, bugs reported with a suggested patch for fixing them will
Daniel Veillardec303412000-03-24 13:41:54 +0000[diff] [blame]458probably be processed faster.</p>
459
460<p>If you're looking for help, a quick look at <a
Daniel Veillardf7ed3362001-08-17 12:01:21 +0000[diff] [blame]461href="http://mail.gnome.org/archives/xml/">the list archive</a> may actually
Daniel Veillardec303412000-03-24 13:41:54 +0000[diff] [blame]462provide the answer, I usually send source samples when answering libxml usage
Daniel Veillard6f0adb52000-07-03 11:41:26 +0000[diff] [blame]463questions. The <a href="http://xmlsoft.org/html/book1.html">auto-generated
Daniel Veillardec303412000-03-24 13:41:54 +0000[diff] [blame]464documentantion</a> is not as polished as I would like (i need to learn more
465about Docbook), but it's a good starting point.</p>
466
Daniel Veillardd5f97f82000-09-17 16:38:14 +0000[diff] [blame]467<h2><a name="help">How to help</a></h2>
468
469<p>You can help the project in various ways, the best thing to do first is to
470subscribe to the mailing-list as explained before, check the <a
Daniel Veillardf7ed3362001-08-17 12:01:21 +0000[diff] [blame]471href="http://mail.gnome.org/archives/xml/">archives </a>and the <a
472href="http://bugzilla.gnome.org/buglist.cgi?product=libxml">Gnome bug
Daniel Veillardd5f97f82000-09-17 16:38:14 +0000[diff] [blame]473database:</a>:</p>
474<ol>
475 <li>provide patches when you find problems</li>
Daniel Veillard189446d2000-10-13 10:23:06 +0000[diff] [blame]476 <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]477 be integrated in all cases but help pinpointing portability problems
478 and</li>
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]479 <li>provide documentation fixes (either as patches to the code comments or
Daniel Veillardd5f97f82000-09-17 16:38:14 +0000[diff] [blame]480 as HTML diffs).</li>
481 <li>provide new documentations pieces (translations, examples, etc ...)</li>
482 <li>Check the TODO file and try to close one of the items</li>
483 <li>take one of the points raised in the archive or the bug database and
Daniel Veillarde7ead2d2001-08-22 23:44:09 +0000[diff] [blame]484 provide a fix. <a href="mailto:daniel@veillard.com">Get in touch with me
485 </a>before to avoid synchronization problems and check that the suggested
486 fix will fit in nicely :-)</li>
Daniel Veillardd5f97f82000-09-17 16:38:14 +0000[diff] [blame]487</ol>
488
Daniel Veillard10a2c651999-12-12 13:03:50 +0000[diff] [blame]489<h2><a name="Downloads">Downloads</a></h2>
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]490
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]491<p>The latest versions of libxml can be found on <a
Daniel Veillard20c8cf22001-06-26 22:47:36 +0000[diff] [blame]492href="ftp://xmlsoft.org/">xmlsoft.org</a> (<a
493href="ftp://speakeasy.rpmfind.net/pub/libxml/">Seattle</a>, <a
494href="ftp://fr.rpmfind.net/pub/libxml/">France</a>) or on the <a
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]495href="ftp://ftp.gnome.org/pub/GNOME/MIRRORS.html">Gnome FTP server</a> either
Daniel Veillard10a2c651999-12-12 13:03:50 +0000[diff] [blame]496as a <a href="ftp://ftp.gnome.org/pub/GNOME/stable/sources/libxml/">source
Daniel Veillard306be992000-07-03 12:38:45 +0000[diff] [blame]497archive</a> or <a
Daniel Veillarda41123c2001-04-22 19:31:20 +0000[diff] [blame]498href="ftp://ftp.gnome.org/pub/GNOME/stable/redhat/i386/libxml/">RPM
499packages</a>. (NOTE that you need both the <a
Daniel Veillardc19fccc2000-07-03 11:52:01 +0000[diff] [blame]500href="http://rpmfind.net/linux/RPM/libxml2.html">libxml(2)</a> and <a
501href="http://rpmfind.net/linux/RPM/libxml2-devel.html">libxml(2)-devel</a>
Daniel Veillard95189532001-07-26 18:30:26 +0000[diff] [blame]502packages installed to compile applications using libxml.) <a
503href="mailto:izlatkovic@daenet.de">Igor Zlatkovic</a> is now the maintainer
504of the Windows port, <a
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]505href="http://www.fh-frankfurt.de/~igor/projects/libxml/index.html">he
Daniel Veillardc6271d22001-10-27 07:50:58 +0000[diff] [blame]506provides binaries</a>. <a href="mailto:Gary.Pennington@sun.com">Gary
Daniel Veillard1aadc442001-11-28 13:10:32 +0000[diff] [blame]507Pennington</a> provides <a href="http://garypennington.net/libxml2/">Solaris
508binaries</a>.</p>
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]509
Daniel Veillard6c8b1172000-03-01 00:40:41 +0000[diff] [blame]510<p><a name="Snapshot">Snapshot:</a></p>
511<ul>
512 <li>Code from the W3C cvs base libxml <a
Daniel Veillard33a67802001-03-07 09:44:02 +0000[diff] [blame]513 href="ftp://xmlsoft.org/cvs-snapshot.tar.gz">cvs-snapshot.tar.gz</a></li>
Daniel Veillard6c8b1172000-03-01 00:40:41 +0000[diff] [blame]514 <li>Docs, content of the web site, the list archive included <a
Daniel Veillard33a67802001-03-07 09:44:02 +0000[diff] [blame]515 href="ftp://xmlsoft.org/libxml-docs.tar.gz">libxml-docs.tar.gz</a></li>
Daniel Veillard6c8b1172000-03-01 00:40:41 +0000[diff] [blame]516</ul>
517
Daniel Veillardc6271d22001-10-27 07:50:58 +0000[diff] [blame]518<p><a name="Contribs">Contributions:</a></p>
Daniel Veillard6c8b1172000-03-01 00:40:41 +0000[diff] [blame]519
520<p>I do accept external contributions, especially if compiling on another
Daniel Veillardc6271d22001-10-27 07:50:58 +0000[diff] [blame]521platform, get in touch with me to upload the package, wrappers for various
Daniel Veillard51095312001-10-28 18:51:57 +0000[diff] [blame]522languages have been provided, and can be found in the <a
523href="contribs.html">contrib section</a></p>
Daniel Veillard6c8b1172000-03-01 00:40:41 +0000[diff] [blame]524
Daniel Veillard82687162001-01-22 15:32:01 +0000[diff] [blame]525<p>Libxml is also available from CVS:</p>
Daniel Veillard10a2c651999-12-12 13:03:50 +0000[diff] [blame]526<ul>
Daniel Veillard10a2c651999-12-12 13:03:50 +0000[diff] [blame]527 <li><p>The <a
528 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]529 CVS base</a>. Check the <a
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]530 href="http://developer.gnome.org/tools/cvs.html">Gnome CVS Tools</a>
531 page; the CVS module is <b>gnome-xml</b>.</p>
Daniel Veillard10a2c651999-12-12 13:03:50 +0000[diff] [blame]532 </li>
Daniel Veillard82687162001-01-22 15:32:01 +0000[diff] [blame]533 <li>The <strong>libxslt</strong> module is also present there</li>
Daniel Veillard10a2c651999-12-12 13:03:50 +0000[diff] [blame]534</ul>
535
536<h2><a name="News">News</a></h2>
537
Daniel Veillard944b5ff1999-12-15 19:08:24 +0000[diff] [blame]538<h3>CVS only : check the <a
539href="http://cvs.gnome.org/lxr/source/gnome-xml/ChangeLog">Changelog</a> file
Daniel Veillard189446d2000-10-13 10:23:06 +0000[diff] [blame]540for a really accurate description</h3>
Daniel Veillardab8500d2000-10-15 21:06:19 +0000[diff] [blame]541
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]542<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]543you want to test those</p>
544<ul>
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]545 <li>Implementing <a href="http://xmlsoft.org/XSLT">XSLT</a>, this is done
546 as a separate C library on top of libxml called libxslt</li>
Daniel Veillard28929b22000-11-13 18:22:49 +0000[diff] [blame]547 <li>Finishing up <a href="http://www.w3.org/TR/xptr">XPointer</a> and <a
548 href="http://www.w3.org/TR/xinclude">XInclude</a></li>
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]549 <li>(seeems working but delayed from release) parsing/import of Docbook
550 SGML docs</li>
551</ul>
552
Daniel Veillard5f4b5992002-02-20 10:22:49 +0000[diff] [blame^]553<h3>2.4.16: Feb 20 2002</h3>
554<ul>
555 <li>a lot of bug fixes, most of them were triggered by the XML Testsuite
556 from OASIS and W3C. Compliance has been significantly improved.</li>
557 <li>a couple of portability fixes too.</li>
558</ul>
559
Daniel Veillard397ff112002-02-11 18:27:20 +0000[diff] [blame]560<h3>2.4.15: Feb 11 2002</h3>
561<ul>
562 <li>Fixed the Makefiles, especially the python module ones</li>
563 <li>A few bug fixes and cleanup</li>
564 <li>Includes cleanup</li>
565</ul>
566
Daniel Veillardb6c1e2f2002-02-08 14:52:52 +0000[diff] [blame]567<h3>2.4.14: Feb 8 2002</h3>
568<ul>
569 <li>Change of Licence to the <a
570 href="http://www.opensource.org/licenses/mit-license.html">MIT
571 Licence</a> basisally for integration in XFree86 codebase, and removing
572 confusion around the previous dual-licencing</li>
573 <li>added Python bindings, beta software but should already be quite
574 complete</li>
575 <li>a large number of fixes and cleanups, especially for all tree
576 manipulations</li>
577 <li>cleanup of the headers, generation of a reference API definition in
578 XML</li>
579</ul>
580
581<h3>2.4.13: Jan 14 2002</h3>
Daniel Veillard744683d2002-01-14 17:30:20 +0000[diff] [blame]582<ul>
583 <li>update of the documentation: John Fleck and Charlie Bozeman</li>
584 <li>cleanup of timing code from Justin Fletcher</li>
585 <li>fixes for Windows and initial thread support on Win32: Igor and Serguei
586 Narojnyi</li>
587 <li>Cygwin patch from Robert Collins</li>
588 <li>added xmlSetEntityReferenceFunc() for Keith Isdale work on xsldbg</li>
589</ul>
590
Daniel Veillardef90ba72001-12-07 14:24:22 +0000[diff] [blame]591<h3>2.4.12: Dec 7 2001</h3>
592<ul>
593 <li>a few bug fixes: thread (Gary Pennington), xmllint (Geert Kloosterman),
594 XML parser (Robin Berjon), XPointer (Danny Jamshy), I/O cleanups
595 (robert)</li>
596 <li>Eric Lavigne contributed project files for MacOS</li>
597 <li>some makefiles cleanups</li>
598</ul>
599
Daniel Veillarda4871052001-11-26 13:19:48 +0000[diff] [blame]600<h3>2.4.11: Nov 26 2001</h3>
601<ul>
602 <li>fixed a couple of errors in the includes, fixed a few bugs, some code
603 cleanups</li>
604 <li>xmllint man pages improvement by Heiko Rupp</li>
605 <li>updated VMS build instructions from John A Fotheringham</li>
606 <li>Windows Makefiles updates from Igor</li>
607</ul>
608
Daniel Veillard43d3f612001-11-10 11:57:23 +0000[diff] [blame]609<h3>2.4.10: Nov 10 2001</h3>
610<ul>
611 <li>URI escaping fix (Joel Young)</li>
612 <li>added xmlGetNodePath() (for paths or XPointers generation)</li>
613 <li>Fixes namespace handling problems when using DTD and validation</li>
614 <li>improvements on xmllint: Morus Walter patches for --format and
615 --encode, Stefan Kost and Heiko Rupp improvements on the --shell</li>
616 <li>fixes for xmlcatalog linking pointed by Weiqi Gao</li>
617 <li>fixes to the HTML parser</li>
618</ul>
619
620<h3>2.4.9: Nov 6 2001</h3>
621<ul>
622 <li>fixes more catalog bugs</li>
623 <li>avoid a compilation problem, improve xmlGetLineNo()</li>
624</ul>
625
Daniel Veillarded421aa2001-11-04 21:22:45 +0000[diff] [blame]626<h3>2.4.8: Nov 4 2001</h3>
627<ul>
628 <li>fixed SGML catalogs broken in previous release, updated xmlcatalog
629 tool</li>
630 <li>fixed a compile errors and some includes troubles.</li>
631</ul>
632
Daniel Veillard52dcab32001-10-30 12:51:17 +0000[diff] [blame]633<h3>2.4.7: Oct 30 2001</h3>
634<ul>
635 <li>exported some debugging interfaces</li>
636 <li>serious rewrite of the catalog code</li>
637 <li>integrated Gary Pennington thread safety patch, added configure option
638 and regression tests</li>
639 <li>removed an HTML parser bug</li>
640 <li>fixed a couple of potentially serious validation bugs</li>
641 <li>integrated the SGML DocBook support in xmllint</li>
642 <li>changed the nanoftp anonymous login passwd</li>
643 <li>some I/O cleanup and a couple of interfaces for Perl wrapper</li>
644 <li>general bug fixes</li>
645 <li>updated xmllint man page by John Fleck</li>
646 <li>some VMS and Windows updates</li>
647</ul>
648
Daniel Veillard60087f32001-10-10 09:45:09 +0000[diff] [blame]649<h3>2.4.6: Oct 10 2001</h3>
650<ul>
Daniel Veillard52dcab32001-10-30 12:51:17 +0000[diff] [blame]651 <li>added an updated man pages by John Fleck</li>
Daniel Veillard60087f32001-10-10 09:45:09 +0000[diff] [blame]652 <li>portability and configure fixes</li>
653 <li>an infinite loop on the HTML parser was removed (William)</li>
654 <li>Windows makefile patches from Igor</li>
655 <li>fixed half a dozen bugs reported fof libxml or libxslt</li>
656 <li>updated xmlcatalog to be able to modify SGML super catalogs</li>
657</ul>
658
Daniel Veillarddadd0872001-09-15 09:21:44 +0000[diff] [blame]659<h3>2.4.5: Sep 14 2001</h3>
660<ul>
661 <li>Remove a few annoying bugs in 2.4.4</li>
662 <li>forces the HTML serializer to output decimal charrefs since some
663 version of Netscape can't handle hexadecimal ones</li>
664</ul>
665
666<h3>1.8.16: Sep 14 2001</h3>
667<ul>
668 <li>maintenance release of the old libxml1 branch, couple of bug and
669 portability fixes</li>
670</ul>
671
Daniel Veillard04382ae2001-09-12 18:51:30 +0000[diff] [blame]672<h3>2.4.4: Sep 12 2001</h3>
673<ul>
674 <li>added --convert to xmlcatalog, bug fixes and cleanups of XML
675 Catalog</li>
676 <li>a few bug fixes and some portability changes</li>
677 <li>some documentation cleanups</li>
678</ul>
679
Daniel Veillard39936902001-08-24 00:49:01 +0000[diff] [blame]680<h3>2.4.3: Aug 23 2001</h3>
681<ul>
682 <li>XML Catalog support see the doc</li>
683 <li>New NaN/Infinity floating point code</li>
684 <li>A few bug fixes</li>
685</ul>
686
687<h3>2.4.2: Aug 15 2001</h3>
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]688<ul>
689 <li>adds xmlLineNumbersDefault() to control line number generation</li>
690 <li>lot of bug fixes</li>
691 <li>the Microsoft MSC projects files shuld now be up to date</li>
692 <li>inheritance of namespaces from DTD defaulted attributes</li>
693 <li>fixes a serious potential security bug</li>
694 <li>added a --format option to xmllint</li>
695</ul>
696
697<h3>2.4.1: July 24 2001</h3>
698<ul>
699 <li>possibility to keep line numbers in the tree</li>
700 <li>some computation NaN fixes</li>
701 <li>extension of the XPath API</li>
702 <li>cleanup for alpha and ia64 targets</li>
703 <li>patch to allow saving through HTTP PUT or POST</li>
Daniel Veillard09ab7e12001-07-10 15:49:44 +0000[diff] [blame]704</ul>
705
706<h3>2.4.0: July 10 2001</h3>
707<ul>
708 <li>Fixed a few bugs in XPath, validation, and tree handling.</li>
709 <li>Fixed XML Base implementation, added a coupel of examples to the
710 regression tests</li>
711 <li>A bit of cleanup</li>
Daniel Veillardab8500d2000-10-15 21:06:19 +0000[diff] [blame]712</ul>
713
Daniel Veillard5b43fde2001-07-05 23:31:40 +0000[diff] [blame]714<h3>2.3.14: July 5 2001</h3>
715<ul>
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]716 <li>fixed some entities problems and reduce mem requirement when
717 substituing them</li>
Daniel Veillard5b43fde2001-07-05 23:31:40 +0000[diff] [blame]718 <li>lots of improvements in the XPath queries interpreter can be
719 substancially faster</li>
720 <li>Makefiles and configure cleanups</li>
721 <li>Fixes to XPath variable eval, and compare on empty node set</li>
722 <li>HTML tag closing bug fixed</li>
723 <li>Fixed an URI reference computating problem when validating</li>
724</ul>
725
Daniel Veillard2adbb512001-06-28 16:20:36 +0000[diff] [blame]726<h3>2.3.13: June 28 2001</h3>
727<ul>
728 <li>2.3.12 configure.in was broken as well as the push mode XML parser</li>
729 <li>a few more fixes for compilation on Windows MSC by Yon Derek</li>
730</ul>
731
732<h3>1.8.14: June 28 2001</h3>
733<ul>
734 <li>Zbigniew Chyla gave a patch to use the old XML parser in push mode</li>
735 <li>Small Makefile fix</li>
736</ul>
737
Daniel Veillard11648102001-06-26 16:08:24 +0000[diff] [blame]738<h3>2.3.12: June 26 2001</h3>
739<ul>
740 <li>lots of cleanup</li>
741 <li>a couple of validation fix</li>
742 <li>fixed line number counting</li>
743 <li>fixed serious problems in the XInclude processing</li>
744 <li>added support for UTF8 BOM at beginning of entities</li>
745 <li>fixed a strange gcc optimizer bugs in xpath handling of float, gcc-3.0
746 miscompile uri.c (William), Thomas Leitner provided a fix for the
747 optimizer on Tru64</li>
748 <li>incorporated Yon Derek and Igor Zlatkovic fixes and improvements for
749 compilation on Windows MSC</li>
750 <li>update of libxml-doc.el (Felix Natter)</li>
751 <li>fixed 2 bugs in URI normalization code</li>
752</ul>
753
Daniel Veillarde3c81b52001-06-17 14:50:34 +0000[diff] [blame]754<h3>2.3.11: June 17 2001</h3>
755<ul>
756 <li>updates to trio, Makefiles and configure should fix some portability
757 problems (alpha)</li>
758 <li>fixed some HTML serialization problems (pre, script, and block/inline
759 handling), added encoding aware APIs, cleanup of this code</li>
760 <li>added xmlHasNsProp()</li>
761 <li>implemented a specific PI for encoding support in the DocBook SGML
762 parser</li>
763 <li>some XPath fixes (-Infinity, / as a function parameter and namespaces
764 node selection)</li>
765 <li>fixed a performance problem and an error in the validation code</li>
766 <li>fixed XInclude routine to implement the recursive behaviour</li>
767 <li>fixed xmlFreeNode problem when libxml is included statically twice</li>
768 <li>added --version to xmllint for bug reports</li>
769</ul>
770
Daniel Veillard2e4f1882001-06-01 10:11:57 +0000[diff] [blame]771<h3>2.3.10: June 1 2001</h3>
772<ul>
773 <li>fixed the SGML catalog support</li>
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]774 <li>a number of reported bugs got fixed, in XPath, iconv detection,
775 XInclude processing</li>
Daniel Veillard2e4f1882001-06-01 10:11:57 +0000[diff] [blame]776 <li>XPath string function should now handle unicode correctly</li>
777</ul>
778
Daniel Veillard4623acd2001-05-19 15:13:15 +0000[diff] [blame]779<h3>2.3.9: May 19 2001</h3>
780
781<p>Lots of bugfixes, and added a basic SGML catalog support:</p>
782<ul>
783 <li>HTML push bugfix #54891 and another patch from Jonas Borgström</li>
784 <li>some serious speed optimisation again</li>
785 <li>some documentation cleanups</li>
786 <li>trying to get better linking on solaris (-R)</li>
787 <li>XPath API cleanup from Thomas Broyer</li>
788 <li>Validation bug fixed #54631, added a patch from Gary Pennington, fixed
789 xmlValidGetValidElements()</li>
790 <li>Added an INSTALL file</li>
791 <li>Attribute removal added to API: #54433</li>
792 <li>added a basic support for SGML catalogs</li>
793 <li>fixed xmlKeepBlanksDefault(0) API</li>
794 <li>bugfix in xmlNodeGetLang()</li>
795 <li>fixed a small configure portability problem</li>
796 <li>fixed an inversion of SYSTEM and PUBLIC identifier in HTML document</li>
797</ul>
798
Daniel Veillarda265af72001-05-14 11:13:58 +0000[diff] [blame]799<h3>1.8.13: May 14 2001</h3>
800<ul>
801 <li>bugfixes release of the old libxml1 branch used by Gnome</li>
802</ul>
803
Daniel Veillard3bbbe6f2001-05-03 11:15:37 +0000[diff] [blame]804<h3>2.3.8: May 3 2001</h3>
805<ul>
806 <li>Integrated an SGML DocBook parser for the Gnome project</li>
807 <li>Fixed a few things in the HTML parser</li>
808 <li>Fixed some XPath bugs raised by XSLT use, tried to fix the floating
809 point portability issue</li>
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]810 <li>Speed improvement (8M/s for SAX, 3M/s for DOM, 1.5M/s for
811 DOM+validation using the XML REC as input and a 700MHz celeron).</li>
Daniel Veillard3bbbe6f2001-05-03 11:15:37 +0000[diff] [blame]812 <li>incorporated more Windows cleanup</li>
813 <li>added xmlSaveFormatFile()</li>
814 <li>fixed problems in copying nodes with entities references (gdome)</li>
815 <li>removed some troubles surrounding the new validation module</li>
816</ul>
817
Daniel Veillarda41123c2001-04-22 19:31:20 +0000[diff] [blame]818<h3>2.3.7: April 22 2001</h3>
819<ul>
820 <li>lots of small bug fixes, corrected XPointer</li>
821 <li>Non determinist content model validation support</li>
822 <li>added xmlDocCopyNode for gdome2</li>
823 <li>revamped the way the HTML parser handles end of tags</li>
824 <li>XPath: corrctions of namespacessupport and number formatting</li>
825 <li>Windows: Igor Zlatkovic patches for MSC compilation</li>
826 <li>HTML ouput fixes from P C Chow and William M. Brack</li>
827 <li>Improved validation speed sensible for DocBook</li>
828 <li>fixed a big bug with ID declared in external parsed entities</li>
829 <li>portability fixes, update of Trio from Bjorn Reese</li>
830</ul>
831
Daniel Veillardafc73112001-04-11 11:51:41 +0000[diff] [blame]832<h3>2.3.6: April 8 2001</h3>
833<ul>
834 <li>Code cleanup using extreme gcc compiler warning options, found and
835 cleared half a dozen potential problem</li>
836 <li>the Eazel team found an XML parser bug</li>
837 <li>cleaned up the user of some of the string formatting function. used the
838 trio library code to provide the one needed when the platform is missing
839 them</li>
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]840 <li>xpath: removed a memory leak and fixed the predicate evaluation
841 problem, extended the testsuite and cleaned up the result. XPointer seems
842 broken ...</li>
Daniel Veillardafc73112001-04-11 11:51:41 +0000[diff] [blame]843</ul>
844
Daniel Veillard56a4cb82001-03-24 17:00:36 +0000[diff] [blame]845<h3>2.3.5: Mar 23 2001</h3>
846<ul>
847 <li>Biggest change is separate parsing and evaluation of XPath expressions,
848 there is some new APIs for this too</li>
849 <li>included a number of bug fixes(XML push parser, 51876, notations,
850 52299)</li>
851 <li>Fixed some portability issues</li>
852</ul>
853
Daniel Veillarde356c282001-03-10 12:32:04 +0000[diff] [blame]854<h3>2.3.4: Mar 10 2001</h3>
855<ul>
856 <li>Fixed bugs #51860 and #51861</li>
857 <li>Added a global variable xmlDefaultBufferSize to allow default buffer
858 size to be application tunable.</li>
859 <li>Some cleanup in the validation code, still a bug left and this part
860 should probably be rewritten to support ambiguous content model :-\</li>
861 <li>Fix a couple of serious bugs introduced or raised by changes in 2.3.3
862 parser</li>
863 <li>Fixed another bug in xmlNodeGetContent()</li>
864 <li>Bjorn fixed XPath node collection and Number formatting</li>
865 <li>Fixed a loop reported in the HTML parsing</li>
866 <li>blank space are reported even if the Dtd content model proves that they
867 are formatting spaces, this is for XmL conformance</li>
868</ul>
869
Daniel Veillardb402c072001-03-01 17:28:58 +0000[diff] [blame]870<h3>2.3.3: Mar 1 2001</h3>
871<ul>
872 <li>small change in XPath for XSLT</li>
873 <li>documentation cleanups</li>
874 <li>fix in validation by Gary Pennington</li>
875 <li>serious parsing performances improvements</li>
876</ul>
877
Daniel Veillardec70e912001-02-26 20:10:45 +0000[diff] [blame]878<h3>2.3.2: Feb 24 2001</h3>
Daniel Veillard71681102001-02-24 17:48:53 +0000[diff] [blame]879<ul>
880 <li>chasing XPath bugs, found a bunch, completed some TODO</li>
881 <li>fixed a Dtd parsing bug</li>
882 <li>fixed a bug in xmlNodeGetContent</li>
883 <li>ID/IDREF support partly rewritten by Gary Pennington</li>
884</ul>
885
Daniel Veillardec70e912001-02-26 20:10:45 +0000[diff] [blame]886<h3>2.3.1: Feb 15 2001</h3>
Daniel Veillard6e6a6cc2001-02-15 15:55:44 +0000[diff] [blame]887<ul>
888 <li>some XPath and HTML bug fixes for XSLT</li>
889 <li>small extension of the hash table interfaces for DOM gdome2
890 implementation</li>
891 <li>A few bug fixes</li>
892</ul>
893
Daniel Veillardec70e912001-02-26 20:10:45 +0000[diff] [blame]894<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]895<ul>
896 <li>Lots of XPath bug fixes</li>
897 <li>Add a mode with Dtd lookup but without validation error reporting for
898 XSLT</li>
899 <li>Add support for text node without escaping (XSLT)</li>
900 <li>bug fixes for xmlCheckFilename</li>
901 <li>validation code bug fixes from Gary Pennington</li>
902 <li>Patch from Paul D. Smith correcting URI path normalization</li>
903 <li>Patch to allow simultaneous install of libxml-devel and
904 libxml2-devel</li>
905 <li>the example Makefile is now fixed</li>
906 <li>added HTML to the RPM packages</li>
907 <li>tree copying bugfixes</li>
908 <li>updates to Windows makefiles</li>
909 <li>optimisation patch from Bjorn Reese</li>
910</ul>
911
Daniel Veillardec70e912001-02-26 20:10:45 +0000[diff] [blame]912<h3>2.2.11: Jan 4 2001</h3>
Daniel Veillard503b8932001-01-05 06:36:31 +0000[diff] [blame]913<ul>
914 <li>bunch of bug fixes (memory I/O, xpath, ftp/http, ...)</li>
915 <li>added htmlHandleOmittedElem()</li>
916 <li>Applied Bjorn Reese's IPV6 first patch</li>
917 <li>Applied Paul D. Smith patches for validation of XInclude results</li>
Daniel Veillard82687162001-01-22 15:32:01 +0000[diff] [blame]918 <li>added XPointer xmlns() new scheme support</li>
Daniel Veillard503b8932001-01-05 06:36:31 +0000[diff] [blame]919</ul>
920
Daniel Veillard2ddd23d2000-11-25 10:42:19 +0000[diff] [blame]921<h3>2.2.10: Nov 25 2000</h3>
Daniel Veillard9d343c42000-11-25 10:12:43 +0000[diff] [blame]922<ul>
923 <li>Fix the Windows problems of 2.2.8</li>
924 <li>integrate OpenVMS patches</li>
925 <li>better handling of some nasty HTML input</li>
926 <li>Improved the XPointer implementation</li>
927 <li>integrate a number of provided patches</li>
928</ul>
929
Daniel Veillard2ddd23d2000-11-25 10:42:19 +0000[diff] [blame]930<h3>2.2.9: Nov 25 2000</h3>
931<ul>
932 <li>erroneous release :-(</li>
933</ul>
934
Daniel Veillard28929b22000-11-13 18:22:49 +0000[diff] [blame]935<h3>2.2.8: Nov 13 2000</h3>
936<ul>
937 <li>First version of <a href="http://www.w3.org/TR/xinclude">XInclude</a>
938 support</li>
939 <li>Patch in conditional section handling</li>
940 <li>updated MS compiler project</li>
941 <li>fixed some XPath problems</li>
942 <li>added an URI escaping function</li>
943 <li>some other bug fixes</li>
944</ul>
945
946<h3>2.2.7: Oct 31 2000</h3>
947<ul>
948 <li>added message redirection</li>
949 <li>XPath improvements (thanks TOM !)</li>
950 <li>xmlIOParseDTD() added</li>
951 <li>various small fixes in the HTML, URI, HTTP and XPointer support</li>
952 <li>some cleanup of the Makefile, autoconf and the distribution content</li>
953</ul>
954
Daniel Veillard29a11cc2000-10-25 13:32:39 +0000[diff] [blame]955<h3>2.2.6: Oct 25 2000:</h3>
956<ul>
957 <li>Added an hash table module, migrated a number of internal structure to
958 those</li>
959 <li>Fixed a posteriori validation problems</li>
960 <li>HTTP module cleanups</li>
961 <li>HTML parser improvements (tag errors, script/style handling, attribute
962 normalization)</li>
963 <li>coalescing of adjacent text nodes</li>
964 <li>couple of XPath bug fixes, exported the internal API</li>
965</ul>
966
Daniel Veillardab8500d2000-10-15 21:06:19 +0000[diff] [blame]967<h3>2.2.5: Oct 15 2000:</h3>
Daniel Veillard4c3a2031999-11-19 17:46:26 +0000[diff] [blame]968<ul>
Daniel Veillard189446d2000-10-13 10:23:06 +0000[diff] [blame]969 <li>XPointer implementation and testsuite</li>
970 <li>Lot of XPath fixes, added variable and functions registration, more
971 tests</li>
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]972 <li>Portability fixes, lots of enhancements toward an easy Windows build
973 and release</li>
Daniel Veillard189446d2000-10-13 10:23:06 +0000[diff] [blame]974 <li>Late validation fixes</li>
975 <li>Integrated a lot of contributed patches</li>
976 <li>added memory management docs</li>
Daniel Veillardab8500d2000-10-15 21:06:19 +0000[diff] [blame]977 <li>a performance problem when using large buffer seems fixed</li>
Daniel Veillard189446d2000-10-13 10:23:06 +0000[diff] [blame]978</ul>
979
980<h3>2.2.4: Oct 1 2000:</h3>
981<ul>
982 <li>main XPath problem fixed</li>
983 <li>Integrated portability patches for Windows</li>
984 <li>Serious bug fixes on the URI and HTML code</li>
Daniel Veillard361d8452000-04-03 19:48:13 +0000[diff] [blame]985</ul>
986
Daniel Veillardd5f97f82000-09-17 16:38:14 +0000[diff] [blame]987<h3>2.2.3: Sep 17 2000</h3>
988<ul>
989 <li>bug fixes</li>
990 <li>cleanup of entity handling code</li>
991 <li>overall review of all loops in the parsers, all sprintf usage has been
992 checked too</li>
993 <li>Far better handling of larges Dtd. Validating against Docbook XML Dtd
994 works smoothly now.</li>
995</ul>
996
997<h3>1.8.10: Sep 6 2000</h3>
998<ul>
999 <li>bug fix release for some Gnome projects</li>
1000</ul>
1001
1002<h3>2.2.2: August 12 2000</h3>
Daniel Veillard786d7c82000-08-12 23:38:57 +0000[diff] [blame]1003<ul>
1004 <li>mostly bug fixes</li>
Daniel Veillardec78c0f2000-08-25 10:25:23 +0000[diff] [blame]1005 <li>started adding routines to access xml parser context options</li>
Daniel Veillard786d7c82000-08-12 23:38:57 +0000[diff] [blame]1006</ul>
1007
Daniel Veillardd5f97f82000-09-17 16:38:14 +0000[diff] [blame]1008<h3>2.2.1: July 21 2000</h3>
Daniel Veillarda2679fa2000-07-22 02:38:15 +0000[diff] [blame]1009<ul>
1010 <li>a purely bug fixes release</li>
1011 <li>fixed an encoding support problem when parsing from a memory block</li>
1012 <li>fixed a DOCTYPE parsing problem</li>
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]1013 <li>removed a bug in the function allowing to override the memory
1014 allocation routines</li>
Daniel Veillarda2679fa2000-07-22 02:38:15 +0000[diff] [blame]1015</ul>
1016
Daniel Veillardd5f97f82000-09-17 16:38:14 +0000[diff] [blame]1017<h3>2.2.0: July 14 2000</h3>
Daniel Veillard94e90602000-07-17 14:38:19 +0000[diff] [blame]1018<ul>
1019 <li>applied a lot of portability fixes</li>
1020 <li>better encoding support/cleanup and saving (content is now always
1021 encoded in UTF-8)</li>
1022 <li>the HTML parser now correctly handles encodings</li>
1023 <li>added xmlHasProp()</li>
1024 <li>fixed a serious problem with &amp;#38;</li>
1025 <li>propagated the fix to FTP client</li>
1026 <li>cleanup, bugfixes, etc ...</li>
1027 <li>Added a page about <a href="encoding.html">libxml Internationalization
1028 support</a></li>
1029</ul>
1030
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]1031<h3>1.8.9: July 9 2000</h3>
1032<ul>
1033 <li>fixed the spec the RPMs should be better</li>
1034 <li>fixed a serious bug in the FTP implementation, released 1.8.9 to solve
1035 rpmfind users problem</li>
1036</ul>
1037
Daniel Veillard6388e172000-07-03 16:07:19 +0000[diff] [blame]1038<h3>2.1.1: July 1 2000</h3>
1039<ul>
1040 <li>fixes a couple of bugs in the 2.1.0 packaging</li>
1041 <li>improvements on the HTML parser</li>
1042</ul>
1043
Daniel Veillard3f6f7f62000-06-30 17:58:25 +0000[diff] [blame]1044<h3>2.1.0 and 1.8.8: June 29 2000</h3>
1045<ul>
1046 <li>1.8.8 is mostly a comodity package for upgrading to libxml2 accoding to
1047 <a href="upgrade.html">new instructions</a>. It fixes a nasty problem
1048 about &amp;#38; charref parsing</li>
1049 <li>2.1.0 also ease the upgrade from libxml v1 to the recent version. it
1050 also contains numerous fixes and enhancements:
1051 <ul>
1052 <li>added xmlStopParser() to stop parsing</li>
1053 <li>improved a lot parsing speed when there is large CDATA blocs</li>
1054 <li>includes XPath patches provided by Picdar Technology</li>
1055 <li>tried to fix as much as possible DtD validation and namespace
1056 related problems</li>
1057 <li>output to a given encoding has been added/tested</li>
1058 <li>lot of various fixes</li>
1059 </ul>
1060 </li>
1061</ul>
1062
Daniel Veillarde0aed302000-04-16 08:52:20 +0000[diff] [blame]1063<h3>2.0.0: Apr 12 2000</h3>
Daniel Veillard361d8452000-04-03 19:48:13 +0000[diff] [blame]1064<ul>
1065 <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]1066 idea to check the 1.x to 2.x upgrade instructions. NOTE: while initally
1067 scheduled for Apr 3 the relase occured only on Apr 12 due to massive
1068 workload.</li>
Daniel Veillard361d8452000-04-03 19:48:13 +0000[diff] [blame]1069 <li>The include are now located under $prefix/include/libxml (instead of
Daniel Veillarde0aed302000-04-16 08:52:20 +0000[diff] [blame]1070 $prefix/include/gnome-xml), they also are referenced by
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]1071 <pre>#include &lt;libxml/xxx.h&gt;</pre>
Daniel Veillarde0aed302000-04-16 08:52:20 +0000[diff] [blame]1072 <p>instead of</p>
Daniel Veillard361d8452000-04-03 19:48:13 +0000[diff] [blame]1073 <pre>#include "xxx.h"</pre>
1074 </li>
Daniel Veillard8f621982000-03-20 13:07:15 +0000[diff] [blame]1075 <li>a new URI module for parsing URIs and following strictly RFC 2396</li>
1076 <li>the memory allocation routines used by libxml can now be overloaded
1077 dynamically by using xmlMemSetup()</li>
Daniel Veillard361d8452000-04-03 19:48:13 +0000[diff] [blame]1078 <li>The previously CVS only tool tester has been renamed
1079 <strong>xmllint</strong> and is now installed as part of the libxml2
1080 package</li>
Daniel Veillarde0aed302000-04-16 08:52:20 +0000[diff] [blame]1081 <li>The I/O interface has been revamped. There is now ways to plug in
1082 specific I/O modules, either at the URI scheme detection level using
1083 xmlRegisterInputCallbacks() or by passing I/O functions when creating a
1084 parser context using xmlCreateIOParserCtxt()</li>
1085 <li>there is a C preprocessor macro LIBXML_VERSION providing the version
1086 number of the libxml module in use</li>
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]1087 <li>a number of optional features of libxml can now be excluded at
1088 configure time (FTP/HTTP/HTML/XPath/Debug)</li>
Daniel Veillardedfb29b2000-03-14 19:59:05 +0000[diff] [blame]1089</ul>
1090
1091<h3>2.0.0beta: Mar 14 2000</h3>
1092<ul>
1093 <li>This is a first Beta release of libxml version 2</li>
Daniel Veillarde356c282001-03-10 12:32:04 +0000[diff] [blame]1094 <li>It's available only from<a href="ftp://xmlsoft.org/">xmlsoft.org
1095 FTP</a>, it's packaged as libxml2-2.0.0beta and available as tar and
1096 RPMs</li>
Daniel Veillardedfb29b2000-03-14 19:59:05 +0000[diff] [blame]1097 <li>This version is now the head in the Gnome CVS base, the old one is
1098 available under the tag LIB_XML_1_X</li>
1099 <li>This includes a very large set of changes. Froma programmatic point of
1100 view applications should not have to be modified too much, check the <a
1101 href="upgrade.html">upgrade page</a></li>
1102 <li>Some interfaces may changes (especially a bit about encoding).</li>
1103 <li>the updates includes:
Daniel Veillard6c8b1172000-03-01 00:40:41 +0000[diff] [blame]1104 <ul>
Daniel Veillardedfb29b2000-03-14 19:59:05 +0000[diff] [blame]1105 <li>fix I18N support. ISO-Latin-x/UTF-8/UTF-16 (nearly) seems correctly
1106 handled now</li>
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]1107 <li>Better handling of entities, especially well formedness checking
1108 and proper PEref extensions in external subsets</li>
Daniel Veillard6c8b1172000-03-01 00:40:41 +0000[diff] [blame]1109 <li>DTD conditional sections</li>
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]1110 <li>Validation now correcly handle entities content</li>
Daniel Veillard6c8b1172000-03-01 00:40:41 +0000[diff] [blame]1111 <li><a href="http://rpmfind.net/tools/gdome/messages/0039.html">change
1112 structures to accomodate DOM</a></li>
Daniel Veillard6c8b1172000-03-01 00:40:41 +0000[diff] [blame]1113 </ul>
1114 </li>
Daniel Veillardedfb29b2000-03-14 19:59:05 +0000[diff] [blame]1115 <li>Serious progress were made toward compliance, <a
1116 href="conf/result.html">here are the result of the test</a> against the
1117 OASIS testsuite (except the japanese tests since I don't support that
1118 encoding yet). This URL is rebuilt every couple of hours using the CVS
1119 head version.</li>
Daniel Veillarde41f2b72000-01-30 20:00:07 +0000[diff] [blame]1120</ul>
1121
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]1122<h3>1.8.7: Mar 6 2000</h3>
1123<ul>
1124 <li>This is a bug fix release:</li>
1125 <li>It is possible to disable the ignorable blanks heuristic used by
1126 libxml-1.x, a new function xmlKeepBlanksDefault(0) will allow this. Note
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]1127 that for adherence to XML spec, this behaviour will be disabled by
1128 default in 2.x . The same function will allow to keep compatibility for
1129 old code.</li>
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]1130 <li>Blanks in &lt;a&gt; &lt;/a&gt; constructs are not ignored anymore,
1131 avoiding heuristic is really the Right Way :-\</li>
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]1132 <li>The unchecked use of snprintf which was breaking libxml-1.8.6
1133 compilation on some platforms has been fixed</li>
1134 <li>nanoftp.c nanohttp.c: Fixed '#' and '?' stripping when processing
1135 URIs</li>
1136</ul>
1137
Daniel Veillarde41f2b72000-01-30 20:00:07 +0000[diff] [blame]1138<h3>1.8.6: Jan 31 2000</h3>
1139<ul>
1140 <li>added a nanoFTP transport module, debugged until the new version of <a
1141 href="http://rpmfind.net/linux/rpm2html/rpmfind.html">rpmfind</a> can use
1142 it without troubles</li>
Daniel Veillardda07c342000-01-25 18:31:22 +0000[diff] [blame]1143</ul>
1144
1145<h3>1.8.5: Jan 21 2000</h3>
1146<ul>
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]1147 <li>adding APIs to parse a well balanced chunk of XML (production <a
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]1148 href="http://www.w3.org/TR/REC-xml#NT-content">[43] content</a> of the
1149 XML spec)</li>
Daniel Veillard461a66c2000-01-18 18:01:01 +0000[diff] [blame]1150 <li>fixed a hideous bug in xmlGetProp pointed by Rune.Djurhuus@fast.no</li>
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]1151 <li>Jody Goldberg &lt;jgoldberg@home.com&gt; provided another patch trying
1152 to solve the zlib checks problems</li>
Daniel Veillard461a66c2000-01-18 18:01:01 +0000[diff] [blame]1153 <li>The current state in gnome CVS base is expected to ship as 1.8.5 with
1154 gnumeric soon</li>
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]1155</ul>
1156
1157<h3>1.8.4: Jan 13 2000</h3>
1158<ul>
1159 <li>bug fixes, reintroduced xmlNewGlobalNs(), fixed xmlNewNs()</li>
1160 <li>all exit() call should have been removed from libxml</li>
1161 <li>fixed a problem with INCLUDE_WINSOCK on WIN32 platform</li>
1162 <li>added newDocFragment()</li>
Daniel Veillardf84f71f2000-01-05 19:54:23 +0000[diff] [blame]1163</ul>
1164
1165<h3>1.8.3: Jan 5 2000</h3>
1166<ul>
1167 <li>a Push interface for the XML and HTML parsers</li>
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]1168 <li>a shell-like interface to the document tree (try tester --shell :-)</li>
Daniel Veillarddbfd6411999-12-28 16:35:14 +0000[diff] [blame]1169 <li>lots of bug fixes and improvement added over XMas hollidays</li>
Daniel Veillard437b87b2000-01-03 17:30:46 +0000[diff] [blame]1170 <li>fixed the DTD parsing code to work with the xhtml DTD</li>
Daniel Veillardf84f71f2000-01-05 19:54:23 +0000[diff] [blame]1171 <li>added xmlRemoveProp(), xmlRemoveID() and xmlRemoveRef()</li>
1172 <li>Fixed bugs in xmlNewNs()</li>
Daniel Veillard437b87b2000-01-03 17:30:46 +0000[diff] [blame]1173 <li>External entity loading code has been revamped, now it uses
Daniel Veillardf84f71f2000-01-05 19:54:23 +0000[diff] [blame]1174 xmlLoadExternalEntity(), some fix on entities processing were added</li>
Daniel Veillard437b87b2000-01-03 17:30:46 +0000[diff] [blame]1175 <li>cleaned up WIN32 includes of socket stuff</li>
Daniel Veillard5cb5ab81999-12-21 15:35:29 +0000[diff] [blame]1176</ul>
1177
1178<h3>1.8.2: Dec 21 1999</h3>
1179<ul>
Daniel Veillardb24054a1999-12-18 15:32:46 +0000[diff] [blame]1180 <li>I got another problem with includes and C++, I hope this issue is fixed
1181 for good this time</li>
Daniel Veillard5cb5ab81999-12-21 15:35:29 +0000[diff] [blame]1182 <li>Added a few tree modification functions: xmlReplaceNode,
1183 xmlAddPrevSibling, xmlAddNextSibling, xmlNodeSetName and
1184 xmlDocSetRootElement</li>
1185 <li>Tried to improve the HTML output with help from <a
1186 href="mailto:clahey@umich.edu">Chris Lahey</a></li>
Daniel Veillarde4e51311999-12-18 15:32:46 +0000[diff] [blame]1187</ul>
Daniel Veillardb24054a1999-12-18 15:32:46 +0000[diff] [blame]1188
Daniel Veillarde4e51311999-12-18 15:32:46 +0000[diff] [blame]1189<h3>1.8.1: Dec 18 1999</h3>
1190<ul>
1191 <li>various patches to avoid troubles when using libxml with C++ compilers
1192 the "namespace" keyword and C escaping in include files</li>
1193 <li>a problem in one of the core macros IS_CHAR was corrected</li>
1194 <li>fixed a bug introduced in 1.8.0 breaking default namespace processing,
1195 and more specifically the Dia application</li>
Daniel Veillard944b5ff1999-12-15 19:08:24 +0000[diff] [blame]1196 <li>fixed a posteriori validation (validation after parsing, or by using a
1197 Dtd not specified in the original document)</li>
Daniel Veillardb24054a1999-12-18 15:32:46 +0000[diff] [blame]1198 <li>fixed a bug in</li>
Daniel Veillard10a2c651999-12-12 13:03:50 +0000[diff] [blame]1199</ul>
1200
1201<h3>1.8.0: Dec 12 1999</h3>
1202<ul>
1203 <li>cleanup, especially memory wise</li>
1204 <li>the parser should be more reliable, especially the HTML one, it should
1205 not crash, whatever the input !</li>
1206 <li>Integrated various patches, especially a speedup improvement for large
1207 dataset from <a href="mailto:cnygard@bellatlantic.net">Carl Nygard</a>,
1208 configure with --with-buffers to enable them.</li>
1209 <li>attribute normalization, oops should have been added long ago !</li>
1210 <li>attributes defaulted from Dtds should be available, xmlSetProp() now
1211 does entities escapting by default.</li>
Daniel Veillard4c3a2031999-11-19 17:46:26 +0000[diff] [blame]1212</ul>
Daniel Veillard35008381999-10-25 13:15:52 +0000[diff] [blame]1213
1214<h3>1.7.4: Oct 25 1999</h3>
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]1215<ul>
Daniel Veillard35008381999-10-25 13:15:52 +0000[diff] [blame]1216 <li>Lots of HTML improvement</li>
1217 <li>Fixed some errors when saving both XML and HTML</li>
1218 <li>More examples, the regression tests should now look clean</li>
1219 <li>Fixed a bug with contiguous charref</li>
1220</ul>
1221
1222<h3>1.7.3: Sep 29 1999</h3>
1223<ul>
1224 <li>portability problems fixed</li>
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]1225 <li>snprintf was used unconditionnally, leading to link problems on system
Daniel Veillard35008381999-10-25 13:15:52 +0000[diff] [blame]1226 were it's not available, fixed</li>
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]1227</ul>
1228
1229<h3>1.7.1: Sep 24 1999</h3>
1230<ul>
1231 <li>The basic type for strings manipulated by libxml has been renamed in
1232 1.7.1 from <strong>CHAR</strong> to <strong>xmlChar</strong>. The reason
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]1233 is that CHAR was conflicting with a predefined type on Windows. However
1234 on non WIN32 environment, compatibility is provided by the way of a
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]1235 <strong>#define </strong>.</li>
1236 <li>Changed another error : the use of a structure field called errno, and
1237 leading to troubles on platforms where it's a macro</li>
1238</ul>
1239
1240<h3>1.7.0: sep 23 1999</h3>
1241<ul>
1242 <li>Added the ability to fetch remote DTD or parsed entities, see the <a
Daniel Veillard9cb5ff42001-01-29 08:22:21 +0000[diff] [blame]1243 href="html/libxml-nanohttp.html">nanohttp</a> module.</li>
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]1244 <li>Added an errno to report errors by another mean than a simple printf
1245 like callback</li>
1246 <li>Finished ID/IDREF support and checking when validation</li>
1247 <li>Serious memory leaks fixed (there is now a <a
Daniel Veillard9cb5ff42001-01-29 08:22:21 +0000[diff] [blame]1248 href="html/libxml-xmlmemory.html">memory wrapper</a> module)</li>
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]1249 <li>Improvement of <a href="http://www.w3.org/TR/xpath">XPath</a>
1250 implementation</li>
1251 <li>Added an HTML parser front-end</li>
1252</ul>
1253
1254<h2><a name="XML">XML</a></h2>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]1255
Daniel Veillard402e8c82000-02-29 22:57:47 +0000[diff] [blame]1256<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]1257markup-based structured documents. Here is <a name="example">an example XML
1258document</a>:</p>
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]1259<pre>&lt;?xml version="1.0"?&gt;
1260&lt;EXAMPLE prop1="gnome is great" prop2="&amp;amp; linux too"&gt;
1261 &lt;head&gt;
1262 &lt;title&gt;Welcome to Gnome&lt;/title&gt;
1263 &lt;/head&gt;
1264 &lt;chapter&gt;
1265 &lt;title&gt;The Linux adventure&lt;/title&gt;
1266 &lt;p&gt;bla bla bla ...&lt;/p&gt;
1267 &lt;image href="linus.gif"/&gt;
1268 &lt;p&gt;...&lt;/p&gt;
1269 &lt;/chapter&gt;
1270&lt;/EXAMPLE&gt;</pre>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]1271
Daniel Veillard402e8c82000-02-29 22:57:47 +0000[diff] [blame]1272<p>The first line specifies that it's an XML document and gives useful
1273information about its encoding. Then the document is a text format whose
1274structure is specified by tags between brackets. <strong>Each tag opened has
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]1275to be closed</strong>. XML is pedantic about this. However, if a tag is empty
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]1276(no content), a single tag can serve as both the opening and closing tag if
1277it ends with <code>/&gt;</code> rather than with <code>&gt;</code>. Note
1278that, for example, the image tag has no content (just an attribute) and is
1279closed by ending the tag with <code>/&gt;</code>.</p>
Daniel Veillardccb09631998-10-27 06:21:04 +0000[diff] [blame]1280
Daniel Veillard402e8c82000-02-29 22:57:47 +0000[diff] [blame]1281<p>XML can be applied sucessfully to a wide range of uses, from long term
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]1282structured document maintenance (where it follows the steps of SGML) to
1283simple data encoding mechanisms like configuration file formatting (glade),
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]1284spreadsheets (gnumeric), or even shorter lived documents such as WebDAV where
1285it is used to encode remote calls between a client and a server.</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]1286
Daniel Veillard82687162001-01-22 15:32:01 +0000[diff] [blame]1287<h2><a name="XSLT">XSLT</a></h2>
1288
Daniel Veillard6e6a6cc2001-02-15 15:55:44 +0000[diff] [blame]1289<p>Check <a href="http://xmlsoft.org/XSLT">the separate libxslt page</a></p>
1290
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]1291<p><a href="http://www.w3.org/TR/xslt">XSL Transformations</a>, is a
1292language for transforming XML documents into other XML documents (or
1293HTML/textual output).</p>
Daniel Veillard82687162001-01-22 15:32:01 +0000[diff] [blame]1294
1295<p>A separate library called libxslt is being built on top of libxml2. This
1296module "libxslt" can be found in the Gnome CVS base too.</p>
1297
Daniel Veillard383b1472001-01-23 11:39:52 +0000[diff] [blame]1298<p>You can check the <a
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]1299href="http://cvs.gnome.org/lxr/source/libxslt/FEATURES">features</a>
1300supported and the progresses on the <a
Daniel Veillard82687162001-01-22 15:32:01 +0000[diff] [blame]1301href="http://cvs.gnome.org/lxr/source/libxslt/ChangeLog">Changelog</a></p>
1302
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]1303<h2><a name="architecture">libxml architecture</a></h2>
Daniel Veillard4540be42000-08-19 16:40:28 +0000[diff] [blame]1304
Daniel Veillardec70e912001-02-26 20:10:45 +0000[diff] [blame]1305<p>Libxml is made of multiple components; some of them are optional, and most
1306of the block interfaces are public. The main components are:</p>
Daniel Veillard4540be42000-08-19 16:40:28 +0000[diff] [blame]1307<ul>
1308 <li>an Input/Output layer</li>
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]1309 <li>FTP and HTTP client layers (optional)</li>
Daniel Veillard4540be42000-08-19 16:40:28 +0000[diff] [blame]1310 <li>an Internationalization layer managing the encodings support</li>
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]1311 <li>a URI module</li>
Daniel Veillard4540be42000-08-19 16:40:28 +0000[diff] [blame]1312 <li>the XML parser and its basic SAX interface</li>
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]1313 <li>an HTML parser using the same SAX interface (optional)</li>
Daniel Veillard4540be42000-08-19 16:40:28 +0000[diff] [blame]1314 <li>a SAX tree module to build an in-memory DOM representation</li>
1315 <li>a tree module to manipulate the DOM representation</li>
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]1316 <li>a validation module using the DOM representation (optional)</li>
Daniel Veillard4540be42000-08-19 16:40:28 +0000[diff] [blame]1317 <li>an XPath module for global lookup in a DOM representation
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]1318 (optional)</li>
1319 <li>a debug module (optional)</li>
Daniel Veillard4540be42000-08-19 16:40:28 +0000[diff] [blame]1320</ul>
1321
1322<p>Graphically this gives the following:</p>
1323
1324<p><img src="libxml.gif" alt="a graphical view of the various"></p>
1325
1326<p></p>
1327
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]1328<h2><a name="tree">The tree output</a></h2>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]1329
1330<p>The parser returns a tree built during the document analysis. The value
Daniel Veillard402e8c82000-02-29 22:57:47 +0000[diff] [blame]1331returned is an <strong>xmlDocPtr</strong> (i.e., a pointer to an
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]1332<strong>xmlDoc</strong> structure). This structure contains information such
Daniel Veillard306be992000-07-03 12:38:45 +0000[diff] [blame]1333as the file name, the document type, and a <strong>children</strong> pointer
1334which is the root of the document (or more exactly the first child under the
1335root which is the document). The tree is made of <strong>xmlNode</strong>s,
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]1336chained in double-linked lists of siblings and with a children&lt;-&gt;parent
Daniel Veillard306be992000-07-03 12:38:45 +0000[diff] [blame]1337relationship. An xmlNode can also carry properties (a chain of xmlAttr
1338structures). An attribute may have a value which is a list of TEXT or
1339ENTITY_REF nodes.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]1340
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]1341<p>Here is an example (erroneous with respect to the XML spec since there
1342should be only one ELEMENT under the root):</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]1343
1344<p><img src="structure.gif" alt=" structure.gif "></p>
1345
1346<p>In the source package there is a small program (not installed by default)
Daniel Veillard361d8452000-04-03 19:48:13 +0000[diff] [blame]1347called <strong>xmllint</strong> which parses XML files given as argument and
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]1348prints them back as parsed. This is useful for detecting errors both in XML
1349code and in the XML parser itself. It has an option <strong>--debug</strong>
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]1350which prints the actual in-memory structure of the document; here is the
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]1351result with the <a href="#example">example</a> given before:</p>
Daniel Veillard10c6a8f1998-10-28 01:00:12 +0000[diff] [blame]1352<pre>DOCUMENT
1353version=1.0
1354standalone=true
1355 ELEMENT EXAMPLE
1356 ATTRIBUTE prop1
1357 TEXT
1358 content=gnome is great
1359 ATTRIBUTE prop2
1360 ENTITY_REF
1361 TEXT
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]1362 content= linux too
Daniel Veillard402e8c82000-02-29 22:57:47 +0000[diff] [blame]1363 ELEMENT head
Daniel Veillard10c6a8f1998-10-28 01:00:12 +0000[diff] [blame]1364 ELEMENT title
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]1365 TEXT
1366 content=Welcome to Gnome
Daniel Veillard10c6a8f1998-10-28 01:00:12 +0000[diff] [blame]1367 ELEMENT chapter
1368 ELEMENT title
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]1369 TEXT
1370 content=The Linux adventure
Daniel Veillard10c6a8f1998-10-28 01:00:12 +0000[diff] [blame]1371 ELEMENT p
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]1372 TEXT
1373 content=bla bla bla ...
Daniel Veillard10c6a8f1998-10-28 01:00:12 +0000[diff] [blame]1374 ELEMENT image
1375 ATTRIBUTE href
1376 TEXT
1377 content=linus.gif
1378 ELEMENT p
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]1379 TEXT
1380 content=...</pre>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]1381
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]1382<p>This should be useful for learning the internal representation model.</p>
Daniel Veillardccb09631998-10-27 06:21:04 +0000[diff] [blame]1383
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]1384<h2><a name="interface">The SAX interface</a></h2>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]1385
Daniel Veillard402e8c82000-02-29 22:57:47 +0000[diff] [blame]1386<p>Sometimes the DOM tree output is just too large to fit reasonably into
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]1387memory. In that case (and if you don't expect to save back the XML document
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]1388loaded using libxml), it's better to use the SAX interface of libxml. SAX is
1389a <strong>callback-based interface</strong> to the parser. Before parsing,
1390the application layer registers a customized set of callbacks which are
1391called by the library as it progresses through the XML input.</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]1392
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]1393<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]1394libxml, see the <a
1395href="http://www.daa.com.au/~james/gnome/xml-sax/xml-sax.html">nice
1396documentation</a>.written by <a href="mailto:james@daa.com.au">James
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]1397Henstridge</a>.</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]1398
1399<p>You can debug the SAX behaviour by using the <strong>testSAX</strong>
1400program located in the gnome-xml module (it's usually not shipped in the
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]1401binary packages of libxml, but you can find it in the tar source
Daniel Veillard402e8c82000-02-29 22:57:47 +0000[diff] [blame]1402distribution). Here is the sequence of callbacks that would be reported by
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]1403testSAX when parsing the example XML document shown earlier:</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]1404<pre>SAX.setDocumentLocator()
1405SAX.startDocument()
1406SAX.getEntity(amp)
1407SAX.startElement(EXAMPLE, prop1='gnome is great', prop2='&amp;amp; linux too')
1408SAX.characters( , 3)
1409SAX.startElement(head)
1410SAX.characters( , 4)
1411SAX.startElement(title)
1412SAX.characters(Welcome to Gnome, 16)
1413SAX.endElement(title)
1414SAX.characters( , 3)
1415SAX.endElement(head)
1416SAX.characters( , 3)
1417SAX.startElement(chapter)
1418SAX.characters( , 4)
1419SAX.startElement(title)
1420SAX.characters(The Linux adventure, 19)
1421SAX.endElement(title)
1422SAX.characters( , 4)
1423SAX.startElement(p)
1424SAX.characters(bla bla bla ..., 15)
1425SAX.endElement(p)
1426SAX.characters( , 4)
1427SAX.startElement(image, href='linus.gif')
1428SAX.endElement(image)
1429SAX.characters( , 4)
1430SAX.startElement(p)
1431SAX.characters(..., 3)
1432SAX.endElement(p)
1433SAX.characters( , 3)
1434SAX.endElement(chapter)
1435SAX.characters( , 1)
1436SAX.endElement(EXAMPLE)
1437SAX.endDocument()</pre>
1438
Daniel Veillardec70e912001-02-26 20:10:45 +0000[diff] [blame]1439<p>Most of the other interfaces of libxml are based on the DOM tree-building
1440facility, so nearly everything up to the end of this document presupposes the
1441use of the standard DOM tree build. Note that the DOM tree itself is built by
1442a set of registered default callbacks, without internal specific
1443interface.</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]1444
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]1445<h2><a name="Validation">Validation &amp; DTDs</a></h2>
1446
1447<p>Table of Content:</p>
1448<ol>
1449 <li><a href="#General5">General overview</a></li>
1450 <li><a href="#definition">The definition</a></li>
1451 <li><a href="#Simple">Simple rules</a>
1452 <ol>
Daniel Veillard9c466822001-10-25 12:03:39 +0000[diff] [blame]1453 <li><a href="#reference">How to reference a DTD from a document</a></li>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]1454 <li><a href="#Declaring">Declaring elements</a></li>
1455 <li><a href="#Declaring1">Declaring attributes</a></li>
1456 </ol>
1457 </li>
1458 <li><a href="#Some">Some examples</a></li>
1459 <li><a href="#validate">How to validate</a></li>
1460 <li><a href="#Other">Other resources</a></li>
1461</ol>
1462
1463<h3><a name="General5">General overview</a></h3>
1464
1465<p>Well what is validation and what is a DTD ?</p>
1466
1467<p>DTD is the acronym for Document Type Definition. This is a description of
1468the content for a familly of XML files. This is part of the XML 1.0
1469specification, and alows to describe and check that a given document instance
1470conforms to a set of rules detailing its structure and content.</p>
1471
1472<p>Validation is the process of checking a document against a DTD (more
1473generally against a set of construction rules).</p>
1474
1475<p>The validation process and building DTDs are the two most difficult parts
1476of the XML life cycle. Briefly a DTD defines all the possibles element to be
1477found within your document, what is the formal shape of your document tree
1478(by defining the allowed content of an element, either text, a regular
1479expression for the allowed list of children, or mixed content i.e. both text
1480and children). The DTD also defines the allowed attributes for all elements
1481and the types of the attributes.</p>
1482
1483<h3><a name="definition1">The definition</a></h3>
1484
1485<p>The <a href="http://www.w3.org/TR/REC-xml">W3C XML Recommendation</a> (<a
1486href="http://www.xml.com/axml/axml.html">Tim Bray's annotated version of
1487Rev1</a>):</p>
1488<ul>
1489 <li><a href="http://www.w3.org/TR/REC-xml#elemdecls">Declaring
1490 elements</a></li>
1491 <li><a href="http://www.w3.org/TR/REC-xml#attdecls">Declaring
1492 attributes</a></li>
1493</ul>
1494
1495<p>(unfortunately) all this is inherited from the SGML world, the syntax is
1496ancient...</p>
1497
1498<h3><a name="Simple1">Simple rules</a></h3>
1499
1500<p>Writing DTD can be done in multiple ways, the rules to build them if you
1501need something fixed or something which can evolve over time can be radically
1502different. Really complex DTD like Docbook ones are flexible but quite harder
1503to design. I will just focuse on DTDs for a formats with a fixed simple
1504structure. It is just a set of basic rules, and definitely not exhaustive nor
1505useable for complex DTD design.</p>
1506
1507<h4><a name="reference1">How to reference a DTD from a document</a>:</h4>
1508
1509<p>Assuming the top element of the document is <code>spec</code> and the dtd
1510is placed in the file <code>mydtd</code> in the subdirectory
1511<code>dtds</code> of the directory from where the document were loaded:</p>
1512
1513<p><code>&lt;!DOCTYPE spec SYSTEM "dtds/mydtd"&gt;</code></p>
1514
1515<p>Notes:</p>
1516<ul>
1517 <li>the system string is actually an URI-Reference (as defined in <a
1518 href="http://www.ietf.org/rfc/rfc2396.txt">RFC 2396</a>) so you can use a
1519 full URL string indicating the location of your DTD on the Web, this is a
1520 really good thing to do if you want others to validate your document</li>
1521 <li>it is also possible to associate a <code>PUBLIC</code> identifier (a
1522 magic string) so that the DTd is looked up in catalogs on the client side
1523 without having to locate it on the web</li>
1524 <li>a dtd contains a set of elements and attributes declarations, but they
1525 don't define what the root of the document should be. This is explicitely
1526 told to the parser/validator as the first element of the
1527 <code>DOCTYPE</code> declaration.</li>
1528</ul>
1529
1530<h4><a name="Declaring2">Declaring elements</a>:</h4>
1531
1532<p>The following declares an element <code>spec</code>:</p>
1533
1534<p><code>&lt;!ELEMENT spec (front, body, back?)&gt;</code></p>
1535
1536<p>it also expresses that the spec element contains one <code>front</code>,
1537one <code>body</code> and one optionnal <code>back</code> children elements
1538in this order. The declaration of one element of the structure and its
1539content are done in a single declaration. Similary the following declares
1540<code>div1</code> elements:</p>
1541
Daniel Veillard51737272002-01-23 23:10:38 +0000[diff] [blame]1542<p><code>&lt;!ELEMENT div1 (head, (p | list | note)*, div2?)&gt;</code></p>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]1543
1544<p>means div1 contains one <code>head</code> then a series of optional
1545<code>p</code>, <code>list</code>s and <code>note</code>s and then an
1546optional <code>div2</code>. And last but not least an element can contain
1547text:</p>
1548
1549<p><code>&lt;!ELEMENT b (#PCDATA)&gt;</code></p>
1550
1551<p><code>b</code> contains text or being of mixed content (text and elements
1552in no particular order):</p>
1553
1554<p><code>&lt;!ELEMENT p (#PCDATA|a|ul|b|i|em)*&gt;</code></p>
1555
1556<p><code>p </code>can contain text or <code>a</code>, <code>ul</code>,
1557<code>b</code>, <code>i </code>or <code>em</code> elements in no particular
1558order.</p>
1559
1560<h4><a name="Declaring1">Declaring attributes</a>:</h4>
1561
1562<p>again the attributes declaration includes their content definition:</p>
1563
1564<p><code>&lt;!ATTLIST termdef name CDATA #IMPLIED&gt;</code></p>
1565
1566<p>means that the element <code>termdef</code> can have a <code>name</code>
1567attribute containing text (<code>CDATA</code>) and which is optionnal
1568(<code>#IMPLIED</code>). The attribute value can also be defined within a
1569set:</p>
1570
1571<p><code>&lt;!ATTLIST list type (bullets|ordered|glossary)
1572"ordered"&gt;</code></p>
1573
1574<p>means <code>list</code> element have a <code>type</code> attribute with 3
1575allowed values "bullets", "ordered" or "glossary" and which default to
1576"ordered" if the attribute is not explicitely specified.</p>
1577
1578<p>The content type of an attribute can be text (<code>CDATA</code>),
1579anchor/reference/references
1580(<code>ID</code>/<code>IDREF</code>/<code>IDREFS</code>), entity(ies)
1581(<code>ENTITY</code>/<code>ENTITIES</code>) or name(s)
1582(<code>NMTOKEN</code>/<code>NMTOKENS</code>). The following defines that a
1583<code>chapter</code> element can have an optional <code>id</code> attribute
1584of type <code>ID</code>, usable for reference from attribute of type
1585IDREF:</p>
1586
1587<p><code>&lt;!ATTLIST chapter id ID #IMPLIED&gt;</code></p>
1588
1589<p>The last value of an attribute definition can be <code>#REQUIRED
1590</code>meaning that the attribute has to be given, <code>#IMPLIED</code>
1591meaning that it is optional, or the default value (possibly prefixed by
1592<code>#FIXED</code> if it is the only allowed).</p>
1593
1594<p>Notes:</p>
1595<ul>
1596 <li>usually the attributes pertaining to a given element are declared in a
1597 single expression, but it is just a convention adopted by a lot of DTD
1598 writers:
1599 <pre>&lt;!ATTLIST termdef
1600 id ID #REQUIRED
1601 name CDATA #IMPLIED&gt;</pre>
1602 <p>The previous construct defines both <code>id</code> and
1603 <code>name</code> attributes for the element <code>termdef</code></p>
1604 </li>
1605</ul>
1606
1607<h3><a name="Some1">Some examples</a></h3>
1608
1609<p>The directory <code>test/valid/dtds/</code> in the libxml distribution
1610contains some complex DTD examples. The <code>test/valid/dia.xml</code>
1611example shows an XML file where the simple DTD is directly included within
1612the document.</p>
1613
1614<h3><a name="validate1">How to validate</a></h3>
1615
1616<p>The simplest is to use the xmllint program comming with libxml. The
1617<code>--valid</code> option turn on validation of the files given as input,
1618for example the following validates a copy of the first revision of the XML
16191.0 specification:</p>
1620
1621<p><code>xmllint --valid --noout test/valid/REC-xml-19980210.xml</code></p>
1622
1623<p>the -- noout is used to not output the resulting tree.</p>
1624
1625<p>The <code>--dtdvalid dtd</code> allows to validate the document(s) against
1626a given DTD.</p>
1627
1628<p>Libxml exports an API to handle DTDs and validation, check the <a
1629href="http://xmlsoft.org/html/libxml-valid.html">associated
1630description</a>.</p>
1631
1632<h3><a name="Other1">Other resources</a></h3>
1633
1634<p>DTDs are as old as SGML. So there may be a number of examples on-line, I
1635will just list one for now, others pointers welcome:</p>
1636<ul>
1637 <li><a href="http://www.xml101.com:8081/dtd/">XML-101 DTD</a></li>
1638</ul>
1639
1640<p>I suggest looking at the examples found under test/valid/dtd and any of
1641the large number of books available on XML. The dia example in test/valid
1642should be both simple and complete enough to allow you to build your own.</p>
1643
1644<p></p>
1645
1646<h2><a name="Memory">Memory Management</a></h2>
1647
1648<p>Table of Content:</p>
1649<ol>
1650 <li><a href="#General3">General overview</a></li>
Daniel Veillard9c466822001-10-25 12:03:39 +0000[diff] [blame]1651 <li><a href="#setting">Setting libxml set of memory routines</a></li>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]1652 <li><a href="#cleanup">Cleaning up after parsing</a></li>
1653 <li><a href="#Debugging">Debugging routines</a></li>
1654 <li><a href="#General4">General memory requirements</a></li>
1655</ol>
1656
1657<h3><a name="General3">General overview</a></h3>
1658
1659<p>The module <code><a
1660href="http://xmlsoft.org/html/libxml-xmlmemory.html">xmlmemory.h</a></code>
1661provides the interfaces to the libxml memory system:</p>
1662<ul>
1663 <li>libxml does not use the libc memory allocator directly but xmlFree(),
1664 xmlMalloc() and xmlRealloc()</li>
1665 <li>those routines can be reallocated to a specific set of routine, by
1666 default the libc ones i.e. free(), malloc() and realloc()</li>
1667 <li>the xmlmemory.c module includes a set of debugging routine</li>
1668</ul>
1669
1670<h3><a name="setting">Setting libxml set of memory routines</a></h3>
1671
1672<p>It is sometimes useful to not use the default memory allocator, either for
1673debugging, analysis or to implement a specific behaviour on memory management
1674(like on embedded systems). Two function calls are available to do so:</p>
1675<ul>
1676 <li><a href="http://xmlsoft.org/html/libxml-xmlmemory.html">xmlMemGet ()</a>
1677 which return the current set of functions in use by the parser</li>
1678 <li><a
1679 href="http://xmlsoft.org/html/libxml-xmlmemory.html">xmlMemSetup()</a>
1680 which allow to set up a new set of memory allocation functions</li>
1681</ul>
1682
1683<p>Of course a call to xmlMemSetup() should probably be done before calling
1684any other libxml routines (unless you are sure your allocations routines are
1685compatibles).</p>
1686
1687<h3><a name="cleanup">Cleaning up after parsing</a></h3>
1688
1689<p>Libxml is not stateless, there is a few set of memory structures needing
1690allocation before the parser is fully functionnal (some encoding structures
1691for example). This also mean that once parsing is finished there is a tiny
1692amount of memory (a few hundred bytes) which can be recollected if you don't
1693reuse the parser immediately:</p>
1694<ul>
1695 <li><a href="http://xmlsoft.org/html/libxml-parser.html">xmlCleanupParser
1696 ()</a>
1697 is a centralized routine to free the parsing states. Note that it won't
1698 deallocate any produced tree if any (use the xmlFreeDoc() and related
1699 routines for this).</li>
1700 <li><a href="http://xmlsoft.org/html/libxml-parser.html">xmlInitParser
1701 ()</a>
1702 is the dual routine allowing to preallocate the parsing state which can
1703 be useful for example to avoid initialization reentrancy problems when
1704 using libxml in multithreaded applications</li>
1705</ul>
1706
1707<p>Generally xmlCleanupParser() is safe, if needed the state will be rebuild
1708at the next invocation of parser routines, but be careful of the consequences
1709in multithreaded applications.</p>
1710
1711<h3><a name="Debugging">Debugging routines</a></h3>
1712
1713<p>When configured using --with-mem-debug flag (off by default), libxml uses
1714a set of memory allocation debugging routineskeeping track of all allocated
1715blocks and the location in the code where the routine was called. A couple of
1716other debugging routines allow to dump the memory allocated infos to a file
1717or call a specific routine when a given block number is allocated:</p>
1718<ul>
1719 <li><a
1720 href="http://xmlsoft.org/html/libxml-xmlmemory.html">xmlMallocLoc()</a>
1721 <a
1722 href="http://xmlsoft.org/html/libxml-xmlmemory.html">xmlReallocLoc()</a>
1723 and <a
1724 href="http://xmlsoft.org/html/libxml-xmlmemory.html">xmlMemStrdupLoc()</a>
1725 are the memory debugging replacement allocation routines</li>
1726 <li><a href="http://xmlsoft.org/html/libxml-xmlmemory.html">xmlMemoryDump
1727 ()</a>
1728 dumps all the informations about the allocated memory block lefts in the
1729 <code>.memdump</code> file</li>
1730</ul>
1731
1732<p>When developping libxml memory debug is enabled, the tests programs call
1733xmlMemoryDump () and the "make test" regression tests will check for any
1734memory leak during the full regression test sequence, this helps a lot
1735ensuring that libxml does not leak memory and bullet proof memory
1736allocations use (some libc implementations are known to be far too permissive
1737resulting in major portability problems!).</p>
1738
1739<p>If the .memdump reports a leak, it displays the allocation function and
1740also tries to give some informations about the content and structure of the
1741allocated blocks left. This is sufficient in most cases to find the culprit,
1742but not always. Assuming the allocation problem is reproductible, it is
1743possible to find more easilly:</p>
1744<ol>
1745 <li>write down the block number xxxx not allocated</li>
1746 <li>export the environement variable XML_MEM_BREAKPOINT=xxxx</li>
1747 <li>run the program under a debugger and set a breakpoint on
1748 xmlMallocBreakpoint() a specific function called when this precise block
1749 is allocated</li>
1750 <li>when the breakpoint is reached you can then do a fine analysis of the
1751 allocation an step to see the condition resulting in the missing
1752 deallocation.</li>
1753</ol>
1754
1755<p>I used to use a commercial tool to debug libxml memory problems but after
1756noticing that it was not detecting memory leaks that simple mechanism was
1757used and proved extremely efficient until now.</p>
1758
1759<h3><a name="General4">General memory requirements</a></h3>
1760
1761<p>How much libxml memory require ? It's hard to tell in average it depends
1762of a number of things:</p>
1763<ul>
1764 <li>the parser itself should work in a fixed amout of memory, except for
1765 information maintained about the stacks of names and entities locations.
1766 The I/O and encoding handlers will probably account for a few KBytes.
1767 This is true for both the XML and HTML parser (though the HTML parser
1768 need more state).</li>
1769 <li>If you are generating the DOM tree then memory requirements will grow
1770 nearly lineary with the size of the data. In general for a balanced
1771 textual document the internal memory requirement is about 4 times the
1772 size of the UTF8 serialization of this document (exmple the XML-1.0
1773 recommendation is a bit more of 150KBytes and takes 650KBytes of main
1774 memory when parsed). Validation will add a amount of memory required for
1775 maintaining the external Dtd state which should be linear with the
1776 complexity of the content model defined by the Dtd</li>
1777 <li>If you don't care about the advanced features of libxml like
1778 validation, DOM, XPath or XPointer, but really need to work fixed memory
1779 requirements, then the SAX interface should be used.</li>
1780</ul>
1781
1782<p></p>
1783
1784<h2><a name="Encodings">Encodings support</a></h2>
1785
1786<p>Table of Content:</p>
1787<ol>
1788 <li><a href="encoding.html#What">What does internationalization support
1789 mean ?</a></li>
1790 <li><a href="encoding.html#internal">The internal encoding, how and
1791 why</a></li>
1792 <li><a href="encoding.html#implemente">How is it implemented ?</a></li>
1793 <li><a href="encoding.html#Default">Default supported encodings</a></li>
1794 <li><a href="encoding.html#extend">How to extend the existing
1795 support</a></li>
1796</ol>
1797
1798<h3><a name="What">What does internationalization support mean ?</a></h3>
1799
1800<p>XML was designed from the start to allow the support of any character set
1801by using Unicode. Any conformant XML parser has to support the UTF-8 and
1802UTF-16 default encodings which can both express the full unicode ranges. UTF8
1803is a variable length encoding whose greatest point are to resuse the same
1804emcoding for ASCII and to save space for Western encodings, but it is a bit
1805more complex to handle in practice. UTF-16 use 2 bytes per characters (and
1806sometimes combines two pairs), it makes implementation easier, but looks a
1807bit overkill for Western languages encoding. Moreover the XML specification
1808allows document to be encoded in other encodings at the condition that they
1809are clearly labelled as such. For example the following is a wellformed XML
1810document encoded in ISO-8859 1 and using accentuated letter that we French
1811likes for both markup and content:</p>
1812<pre>&lt;?xml version="1.0" encoding="ISO-8859-1"?&gt;
1813&lt;très&gt;là&lt;/très&gt;</pre>
1814
1815<p>Having internationalization support in libxml means the foolowing:</p>
1816<ul>
1817 <li>the document is properly parsed</li>
1818 <li>informations about it's encoding are saved</li>
1819 <li>it can be modified</li>
1820 <li>it can be saved in its original encoding</li>
1821 <li>it can also be saved in another encoding supported by libxml (for
1822 example straight UTF8 or even an ASCII form)</li>
1823</ul>
1824
1825<p>Another very important point is that the whole libxml API, with the
1826exception of a few routines to read with a specific encoding or save to a
1827specific encoding, is completely agnostic about the original encoding of the
1828document.</p>
1829
1830<p>It should be noted too that the HTML parser embedded in libxml now obbey
1831the same rules too, the following document will be (as of 2.2.2) handled in
1832an internationalized fashion by libxml too:</p>
1833<pre>&lt;!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"
1834 "http://www.w3.org/TR/REC-html40/loose.dtd"&gt;
1835&lt;html lang="fr"&gt;
1836&lt;head&gt;
1837 &lt;META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=ISO-8859-1"&gt;
1838&lt;/head&gt;
1839&lt;body&gt;
1840&lt;p&gt;W3C crée des standards pour le Web.&lt;/body&gt;
1841&lt;/html&gt;</pre>
1842
1843<h3><a name="internal">The internal encoding, how and why</a></h3>
1844
1845<p>One of the core decision was to force all documents to be converted to a
1846default internal encoding, and that encoding to be UTF-8, here are the
1847rationale for those choices:</p>
1848<ul>
1849 <li>keeping the native encoding in the internal form would force the libxml
1850 users (or the code associated) to be fully aware of the encoding of the
1851 original document, for examples when adding a text node to a document,
1852 the content would have to be provided in the document encoding, i.e. the
1853 client code would have to check it before hand, make sure it's conformant
1854 to the encoding, etc ... Very hard in practice, though in some specific
1855 cases this may make sense.</li>
1856 <li>the second decision was which encoding. From the XML spec only UTF8 and
1857 UTF16 really makes sense as being the two only encodings for which there
1858 is amndatory support. UCS-4 (32 bits fixed size encoding) could be
1859 considered an intelligent choice too since it's a direct Unicode mapping
1860 support. I selected UTF-8 on the basis of efficiency and compatibility
1861 with surrounding software:
1862 <ul>
1863 <li>UTF-8 while a bit more complex to convert from/to (i.e. slightly
1864 more costly to import and export CPU wise) is also far more compact
1865 than UTF-16 (and UCS-4) for a majority of the documents I see it used
1866 for right now (RPM RDF catalogs, advogato data, various configuration
1867 file formats, etc.) and the key point for today's computer
1868 architecture is efficient uses of caches. If one nearly double the
1869 memory requirement to store the same amount of data, this will trash
1870 caches (main memory/external caches/internal caches) and my take is
1871 that this harms the system far more than the CPU requirements needed
1872 for the conversion to UTF-8</li>
1873 <li>Most of libxml version 1 users were using it with straight ASCII
1874 most of the time, doing the conversion with an internal encoding
1875 requiring all their code to be rewritten was a serious show-stopper
1876 for using UTF-16 or UCS-4.</li>
1877 <li>UTF-8 is being used as the de-facto internal encoding standard for
1878 related code like the <a href="http://www.pango.org/">pango</a>
1879 upcoming Gnome text widget, and a lot of Unix code (yep another place
1880 where Unix programmer base takes a different approach from Microsoft
1881 - they are using UTF-16)</li>
1882 </ul>
1883 </li>
1884</ul>
1885
1886<p>What does this mean in practice for the libxml user:</p>
1887<ul>
1888 <li>xmlChar, the libxml data type is a byte, those bytes must be assembled
1889 as UTF-8 valid strings. The proper way to terminate an xmlChar * string
1890 is simply to append 0 byte, as usual.</li>
1891 <li>One just need to make sure that when using chars outside the ASCII set,
1892 the values has been properly converted to UTF-8</li>
1893</ul>
1894
1895<h3><a name="implemente">How is it implemented ?</a></h3>
1896
1897<p>Let's describe how all this works within libxml, basically the I18N
1898(internationalization) support get triggered only during I/O operation, i.e.
1899when reading a document or saving one. Let's look first at the reading
1900sequence:</p>
1901<ol>
1902 <li>when a document is processed, we usually don't know the encoding, a
1903 simple heuristic allows to detect UTF-18 and UCS-4 from whose where the
1904 ASCII range (0-0x7F) maps with ASCII</li>
1905 <li>the xml declaration if available is parsed, including the encoding
1906 declaration. At that point, if the autodetected encoding is different
1907 from the one declared a call to xmlSwitchEncoding() is issued.</li>
1908 <li>If there is no encoding declaration, then the input has to be in either
1909 UTF-8 or UTF-16, if it is not then at some point when processing the
1910 input, the converter/checker of UTF-8 form will raise an encoding error.
1911 You may end-up with a garbled document, or no document at all ! Example:
1912 <pre>~/XML -&gt; ./xmllint err.xml
1913err.xml:1: error: Input is not proper UTF-8, indicate encoding !
1914&lt;très&gt;là&lt;/très&gt;
1915 ^
1916err.xml:1: error: Bytes: 0xE8 0x73 0x3E 0x6C
1917&lt;très&gt;là&lt;/très&gt;
1918 ^</pre>
1919 </li>
1920 <li>xmlSwitchEncoding() does an encoding name lookup, canonalize it, and
1921 then search the default registered encoding converters for that encoding.
1922 If it's not within the default set and iconv() support has been compiled
1923 it, it will ask iconv for such an encoder. If this fails then the parser
1924 will report an error and stops processing:
1925 <pre>~/XML -&gt; ./xmllint err2.xml
1926err2.xml:1: error: Unsupported encoding UnsupportedEnc
1927&lt;?xml version="1.0" encoding="UnsupportedEnc"?&gt;
1928 ^</pre>
1929 </li>
1930 <li>From that point the encoder process progressingly the input (it is
1931 plugged as a front-end to the I/O module) for that entity. It captures
1932 and convert on-the-fly the document to be parsed to UTF-8. The parser
1933 itself just does UTF-8 checking of this input and process it
1934 transparently. The only difference is that the encoding information has
1935 been added to the parsing context (more precisely to the input
1936 corresponding to this entity).</li>
1937 <li>The result (when using DOM) is an internal form completely in UTF-8
1938 with just an encoding information on the document node.</li>
1939</ol>
1940
1941<p>Ok then what's happen when saving the document (assuming you
1942colllected/built an xmlDoc DOM like structure) ? It depends on the function
1943called, xmlSaveFile() will just try to save in the original encoding, while
1944xmlSaveFileTo() and xmlSaveFileEnc() can optionally save to a given
1945encoding:</p>
1946<ol>
1947 <li>if no encoding is given, libxml will look for an encoding value
1948 associated to the document and if it exists will try to save to that
1949 encoding,
1950 <p>otherwise everything is written in the internal form, i.e. UTF-8</p>
1951 </li>
1952 <li>so if an encoding was specified, either at the API level or on the
1953 document, libxml will again canonalize the encoding name, lookup for a
1954 converter in the registered set or through iconv. If not found the
1955 function will return an error code</li>
1956 <li>the converter is placed before the I/O buffer layer, as another kind of
1957 buffer, then libxml will simply push the UTF-8 serialization to through
1958 that buffer, which will then progressively be converted and pushed onto
1959 the I/O layer.</li>
1960 <li>It is possible that the converter code fails on some input, for example
1961 trying to push an UTF-8 encoded chinese character through the UTF-8 to
1962 ISO-8859-1 converter won't work. Since the encoders are progressive they
1963 will just report the error and the number of bytes converted, at that
1964 point libxml will decode the offending character, remove it from the
1965 buffer and replace it with the associated charRef encoding &amp;#123; and
1966 resume the convertion. This guarante that any document will be saved
1967 without losses (except for markup names where this is not legal, this is
1968 a problem in the current version, in pactice avoid using non-ascci
1969 characters for tags or attributes names @@). A special "ascii" encoding
1970 name is used to save documents to a pure ascii form can be used when
1971 portability is really crucial</li>
1972</ol>
1973
1974<p>Here is a few examples based on the same test document:</p>
1975<pre>~/XML -&gt; ./xmllint isolat1
1976&lt;?xml version="1.0" encoding="ISO-8859-1"?&gt;
1977&lt;très&gt;là&lt;/très&gt;
1978~/XML -&gt; ./xmllint --encode UTF-8 isolat1
1979&lt;?xml version="1.0" encoding="UTF-8"?&gt;
1980&lt;très&gt;là  &lt;/très&gt;
1981~/XML -&gt; </pre>
1982
1983<p>The same processing is applied (and reuse most of the code) for HTML I18N
1984processing. Looking up and modifying the content encoding is a bit more
1985difficult since it is located in a &lt;meta&gt; tag under the &lt;head&gt;,
1986so a couple of functions htmlGetMetaEncoding() and htmlSetMetaEncoding() have
1987been provided. The parser also attempts to switch encoding on the fly when
1988detecting such a tag on input. Except for that the processing is the same
1989(and again reuses the same code).</p>
1990
1991<h3><a name="Default">Default supported encodings</a></h3>
1992
1993<p>libxml has a set of default converters for the following encodings
1994(located in encoding.c):</p>
1995<ol>
1996 <li>UTF-8 is supported by default (null handlers)</li>
1997 <li>UTF-16, both little and big endian</li>
1998 <li>ISO-Latin-1 (ISO-8859-1) covering most western languages</li>
1999 <li>ASCII, useful mostly for saving</li>
2000 <li>HTML, a specific handler for the conversion of UTF-8 to ASCII with HTML
2001 predefined entities like &amp;copy; for the Copyright sign.</li>
2002</ol>
2003
2004<p>More over when compiled on an Unix platfor with iconv support the full set
2005of encodings supported by iconv can be instantly be used by libxml. On a
2006linux machine with glibc-2.1 the list of supported encodings and aliases fill
20073 full pages, and include UCS-4, the full set of ISO-Latin encodings, and the
2008various Japanese ones.</p>
2009
2010<h4>Encoding aliases</h4>
2011
2012<p>From 2.2.3, libxml has support to register encoding names aliases. The
2013goal is to be able to parse document whose encoding is supported but where
2014the name differs (for example from the default set of names accepted by
2015iconv). The following functions allow to register and handle new aliases for
2016existing encodings. Once registered libxml will automatically lookup the
2017aliases when handling a document:</p>
2018<ul>
2019 <li>int xmlAddEncodingAlias(const char *name, const char *alias);</li>
2020 <li>int xmlDelEncodingAlias(const char *alias);</li>
2021 <li>const char * xmlGetEncodingAlias(const char *alias);</li>
2022 <li>void xmlCleanupEncodingAliases(void);</li>
2023</ul>
2024
2025<h3><a name="extend">How to extend the existing support</a></h3>
2026
2027<p>Well adding support for new encoding, or overriding one of the encoders
2028(assuming it is buggy) should not be hard, just write an input and output
2029conversion routines to/from UTF-8, and register them using
2030xmlNewCharEncodingHandler(name, xxxToUTF8, UTF8Toxxx), and they will be
2031called automatically if the parser(s) encounter such an encoding name
2032(register it uppercase, this will help). The description of the encoders,
2033their arguments and expected return values are described in the encoding.h
2034header.</p>
2035
2036<p>A quick note on the topic of subverting the parser to use a different
2037internal encoding than UTF-8, in some case people will absolutely want to
2038keep the internal encoding different, I think it's still possible (but the
2039encoding must be compliant with ASCII on the same subrange) though I didn't
2040tried it. The key is to override the default conversion routines (by
2041registering null encoders/decoders for your charsets), and bypass the UTF-8
2042checking of the parser by setting the parser context charset
2043(ctxt-&gt;charset) to something different than XML_CHAR_ENCODING_UTF8, but
2044there is no guarantee taht this will work. You may also have some troubles
2045saving back.</p>
2046
2047<p>Basically proper I18N support is important, this requires at least
2048libxml-2.0.0, but a lot of features and corrections are really available only
2049starting 2.2.</p>
2050
2051<h2><a name="IO">I/O Interfaces</a></h2>
2052
2053<p>Table of Content:</p>
2054<ol>
2055 <li><a href="#General1">General overview</a></li>
2056 <li><a href="#basic">The basic buffer type</a></li>
2057 <li><a href="#Input">Input I/O handlers</a></li>
2058 <li><a href="#Output">Output I/O handlers</a></li>
2059 <li><a href="#entities">The entities loader</a></li>
2060 <li><a href="#Example2">Example of customized I/O</a></li>
2061</ol>
2062
2063<h3><a name="General1">General overview</a></h3>
2064
2065<p>The module <code><a
2066href="http://xmlsoft.org/html/libxml-xmlio.html">xmlIO.h</a></code> provides
2067the interfaces to the libxml I/O system. This consists of 4 main parts:</p>
2068<ul>
2069 <li>Entities loader, this is a routine which tries to fetch the entities
2070 (files) based on their PUBLIC and SYSTEM identifiers. The default loader
2071 don't look at the public identifier since libxml do not maintain a
2072 catalog. You can redefine you own entity loader by using
2073 <code>xmlGetExternalEntityLoader()</code> and
Daniel Veillard9c466822001-10-25 12:03:39 +0000[diff] [blame]2074 <code>xmlSetExternalEntityLoader()</code>. <a href="#entities">Check the
2075 example</a>.</li>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2076 <li>Input I/O buffers which are a commodity structure used by the parser(s)
2077 input layer to handle fetching the informations to feed the parser. This
2078 provides buffering and is also a placeholder where the encoding
2079 convertors to UTF8 are piggy-backed.</li>
2080 <li>Output I/O buffers are similar to the Input ones and fulfill similar
2081 task but when generating a serialization from a tree.</li>
2082 <li>A mechanism to register sets of I/O callbacks and associate them with
2083 specific naming schemes like the protocol part of the URIs.
2084 <p>This affect the default I/O operations and allows to use specific I/O
2085 handlers for certain names.</p>
2086 </li>
2087</ul>
2088
2089<p>The general mechanism used when loading http://rpmfind.net/xml.html for
2090example in the HTML parser is the following:</p>
2091<ol>
2092 <li>The default entity loader calls <code>xmlNewInputFromFile()</code> with
2093 the parsing context and the URI string.</li>
2094 <li>the URI string is checked against the existing registered handlers
2095 using their match() callback function, if the HTTP module was compiled
2096 in, it is registered and its match() function will succeeds</li>
2097 <li>the open() function of the handler is called and if successful will
2098 return an I/O Input buffer</li>
2099 <li>the parser will the start reading from this buffer and progressively
2100 fetch information from the resource, calling the read() function of the
2101 handler until the resource is exhausted</li>
2102 <li>if an encoding change is detected it will be installed on the input
2103 buffer, providing buffering and efficient use of the conversion
2104 routines</li>
2105 <li>once the parser has finished, the close() function of the handler is
2106 called once and the Input buffer and associed resources are
2107 deallocated.</li>
2108</ol>
2109
2110<p>The user defined callbacks are checked first to allow overriding of the
2111default libxml I/O routines.</p>
2112
2113<h3><a name="basic">The basic buffer type</a></h3>
2114
2115<p>All the buffer manipulation handling is done using the
2116<code>xmlBuffer</code> type define in <code><a
2117href="http://xmlsoft.org/html/libxml-tree.html">tree.h</a> </code>which is a
2118resizable memory buffer. The buffer allocation strategy can be selected to be
2119either best-fit or use an exponential doubling one (CPU vs. memory use
2120tradeoff). The values are <code>XML_BUFFER_ALLOC_EXACT</code> and
2121<code>XML_BUFFER_ALLOC_DOUBLEIT</code>, and can be set individually or on a
2122system wide basis using <code>xmlBufferSetAllocationScheme()</code>. A number
2123of functions allows to manipulate buffers with names starting with the
2124<code>xmlBuffer...</code> prefix.</p>
2125
2126<h3><a name="Input">Input I/O handlers</a></h3>
2127
2128<p>An Input I/O handler is a simple structure
2129<code>xmlParserInputBuffer</code> containing a context associated to the
2130resource (file descriptor, or pointer to a protocol handler), the read() and
2131close() callbacks to use and an xmlBuffer. And extra xmlBuffer and a charset
2132encoding handler are also present to support charset conversion when
2133needed.</p>
2134
2135<h3><a name="Output">Output I/O handlers</a></h3>
2136
2137<p>An Output handler <code>xmlOutputBuffer</code> is completely similar to an
2138Input one except the callbacks are write() and close().</p>
2139
2140<h3><a name="entities">The entities loader</a></h3>
2141
2142<p>The entity loader resolves requests for new entities and create inputs for
2143the parser. Creating an input from a filename or an URI string is done
2144through the xmlNewInputFromFile() routine. The default entity loader do not
2145handle the PUBLIC identifier associated with an entity (if any). So it just
2146calls xmlNewInputFromFile() with the SYSTEM identifier (which is mandatory in
2147XML).</p>
2148
2149<p>If you want to hook up a catalog mechanism then you simply need to
2150override the default entity loader, here is an example:</p>
2151<pre>#include &lt;libxml/xmlIO.h&gt;
2152
2153xmlExternalEntityLoader defaultLoader = NULL;
2154
2155xmlParserInputPtr
2156xmlMyExternalEntityLoader(const char *URL, const char *ID,
2157 xmlParserCtxtPtr ctxt) {
2158 xmlParserInputPtr ret;
2159 const char *fileID = NULL;
2160 /* lookup for the fileID depending on ID */
2161
2162 ret = xmlNewInputFromFile(ctxt, fileID);
2163 if (ret != NULL)
2164 return(ret);
2165 if (defaultLoader != NULL)
2166 ret = defaultLoader(URL, ID, ctxt);
2167 return(ret);
2168}
2169
2170int main(..) {
2171 ...
2172
2173 /*
2174 * Install our own entity loader
2175 */
2176 defaultLoader = xmlGetExternalEntityLoader();
2177 xmlSetExternalEntityLoader(xmlMyExternalEntityLoader);
2178
2179 ...
2180}</pre>
2181
2182<h3><a name="Example2">Example of customized I/O</a></h3>
2183
2184<p>This example come from <a href="http://xmlsoft.org/messages/0708.html">a
2185real use case</a>, xmlDocDump() closes the FILE * passed by the application
2186and this was a problem. The <a
2187href="http://xmlsoft.org/messages/0711.html">solution</a> was to redefine a
2188new output handler with the closing call deactivated:</p>
2189<ol>
2190 <li>First define a new I/O ouput allocator where the output don't close the
2191 file:
2192 <pre>xmlOutputBufferPtr
2193xmlOutputBufferCreateOwn(FILE *file, xmlCharEncodingHandlerPtr encoder) {
2194    xmlOutputBufferPtr ret;
2195    
2196    if (xmlOutputCallbackInitialized == 0)
2197        xmlRegisterDefaultOutputCallbacks();
2198
2199    if (file == NULL) return(NULL);
2200    ret = xmlAllocOutputBuffer(encoder);
2201    if (ret != NULL) {
2202        ret-&gt;context = file;
2203        ret-&gt;writecallback = xmlFileWrite;
2204        ret-&gt;closecallback = NULL; /* No close callback */
2205    }
2206    return(ret); <br>
2207
2208
2209
Daniel Veillard9c466822001-10-25 12:03:39 +0000[diff] [blame]2210
2211
Daniel Veillardc6271d22001-10-27 07:50:58 +0000[diff] [blame]2212
Daniel Veillard51095312001-10-28 18:51:57 +0000[diff] [blame]2213
Daniel Veillard52dcab32001-10-30 12:51:17 +0000[diff] [blame]2214
Daniel Veillarded421aa2001-11-04 21:22:45 +0000[diff] [blame]2215
Daniel Veillard43d3f612001-11-10 11:57:23 +0000[diff] [blame]2216
Daniel Veillarda4871052001-11-26 13:19:48 +0000[diff] [blame]2217
Daniel Veillard1aadc442001-11-28 13:10:32 +0000[diff] [blame]2218
Daniel Veillardef90ba72001-12-07 14:24:22 +0000[diff] [blame]2219
Daniel Veillard9ae4b7a2001-12-13 14:24:09 +0000[diff] [blame]2220
Daniel Veillard845cce42002-01-09 11:51:37 +0000[diff] [blame]2221
Daniel Veillard744683d2002-01-14 17:30:20 +0000[diff] [blame]2222
Daniel Veillard35e937a2002-01-19 22:21:54 +0000[diff] [blame]2223
Daniel Veillardc575b992002-02-08 13:28:40 +0000[diff] [blame]2224
Daniel Veillardb6c1e2f2002-02-08 14:52:52 +0000[diff] [blame]2225
Daniel Veillard397ff112002-02-11 18:27:20 +0000[diff] [blame]2226
Daniel Veillarde46182c2002-02-12 14:29:11 +0000[diff] [blame]2227
Daniel Veillard5f4b5992002-02-20 10:22:49 +0000[diff] [blame^]2228
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2229} </pre>
2230 </li>
2231 <li>And then use it to save the document:
2232 <pre>FILE *f;
2233xmlOutputBufferPtr output;
2234xmlDocPtr doc;
2235int res;
2236
2237f = ...
2238doc = ....
2239
2240output = xmlOutputBufferCreateOwn(f, NULL);
2241res = xmlSaveFileTo(output, doc, NULL);
2242 </pre>
2243 </li>
2244</ol>
2245
2246<h2><a name="Catalog">Catalog support</a></h2>
2247
2248<p>Table of Content:</p>
2249<ol>
2250 <li><a href="General2">General overview</a></li>
2251 <li><a href="#definition">The definition</a></li>
2252 <li><a href="#Simple">Using catalogs</a></li>
2253 <li><a href="#Some">Some examples</a></li>
2254 <li><a href="#reference">How to tune catalog usage</a></li>
2255 <li><a href="#validate">How to debug catalog processing</a></li>
2256 <li><a href="#Declaring">How to create and maintain catalogs</a></li>
2257 <li><a href="#implemento">The implementor corner quick review of the
2258 API</a></li>
2259 <li><a href="#Other">Other resources</a></li>
2260</ol>
2261
2262<h3><a name="General2">General overview</a></h3>
2263
2264<p>What is a catalog? Basically it's a lookup mechanism used when an entity
2265(a file or a remote resource) references another entity. The catalog lookup
2266is inserted between the moment the reference is recognized by the software
2267(XML parser, stylesheet processing, or even images referenced for inclusion
2268in a rendering) and the time where loading that resource is actually
2269started.</p>
2270
2271<p>It is basically used for 3 things:</p>
2272<ul>
2273 <li>mapping from "logical" names, the public identifiers and a more
2274 concrete name usable for download (and URI). For example it can associate
2275 the logical name
2276 <p>"-//OASIS//DTD DocBook XML V4.1.2//EN"</p>
2277 <p>of the DocBook 4.1.2 XML DTD with the actual URL where it can be
2278 downloaded</p>
2279 <p>http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd</p>
2280 </li>
2281 <li>remapping from a given URL to another one, like an HTTP indirection
2282 saying that
2283 <p>"http://www.oasis-open.org/committes/tr.xsl"</p>
2284 <p>should really be looked at</p>
2285 <p>"http://www.oasis-open.org/committes/entity/stylesheets/base/tr.xsl"</p>
2286 </li>
2287 <li>providing a local cache mechanism allowing to load the entities
2288 associated to public identifiers or remote resources, this is a really
2289 important feature for any significant deployment of XML or SGML since it
2290 allows to avoid the aleas and delays associated to fetching remote
2291 resources.</li>
2292</ul>
2293
2294<h3><a name="definition">The definitions</a></h3>
2295
2296<p>Libxml, as of 2.4.3 implements 2 kind of catalogs:</p>
2297<ul>
2298 <li>the older SGML catalogs, the official spec is SGML Open Technical
2299 Resolution TR9401:1997, but is better understood by reading <a
2300 href="http://www.jclark.com/sp/catalog.htm">the SP Catalog page</a> from
2301 James Clark. This is relatively old and not the preferred mode of
2302 operation of libxml.</li>
2303 <li><a href="http://www.oasis-open.org/committees/entity/spec.html">XML
2304 Catalogs</a>
2305 is far more flexible, more recent, uses an XML syntax and should scale
2306 quite better. This is the default option of libxml.</li>
2307</ul>
2308
2309<p></p>
2310
2311<h3><a name="Simple">Using catalog</a></h3>
2312
2313<p>In a normal environment libxml will by default check the presence of a
2314catalog in /etc/xml/catalog, and assuming it has been correctly populated,
2315the processing is completely transparent to the document user. To take a
2316concrete example, suppose you are authoring a DocBook document, this one
2317starts with the following DOCTYPE definition:</p>
2318<pre>&lt;?xml version='1.0'?&gt;
2319&lt;!DOCTYPE book PUBLIC "-//Norman Walsh//DTD DocBk XML V3.1.4//EN"
2320 "http://nwalsh.com/docbook/xml/3.1.4/db3xml.dtd"&gt;</pre>
2321
2322<p>When validating the document with libxml, the catalog will be
2323automatically consulted to lookup the public identifier "-//Norman Walsh//DTD
2324DocBk XML V3.1.4//EN" and the system identifier
2325"http://nwalsh.com/docbook/xml/3.1.4/db3xml.dtd", and if these entities have
2326been installed on your system and the catalogs actually point to them, libxml
2327will fetch them from the local disk.</p>
2328
2329<p style="font-size: 10pt"><strong>Note</strong>: Really don't use this
2330DOCTYPE example it's a really old version, but is fine as an example.</p>
2331
2332<p>Libxml will check the catalog each time that it is requested to load an
2333entity, this includes DTD, external parsed entities, stylesheets, etc ... If
2334your system is correctly configured all the authoring phase and processing
2335should use only local files, even if your document stays portable because it
2336uses the canonical public and system ID, referencing the remote document.</p>
2337
2338<h3><a name="Some">Some examples:</a></h3>
2339
2340<p>Here is a couple of fragments from XML Catalogs used in libxml early
2341regression tests in <code>test/catalogs</code> :</p>
2342<pre>&lt;?xml version="1.0"?&gt;
2343&lt;!DOCTYPE catalog PUBLIC
2344 "-//OASIS//DTD Entity Resolution XML Catalog V1.0//EN"
2345 "http://www.oasis-open.org/committees/entity/release/1.0/catalog.dtd"&gt;
2346&lt;catalog xmlns="urn:oasis:names:tc:entity:xmlns:xml:catalog"&gt;
2347 &lt;public publicId="-//OASIS//DTD DocBook XML V4.1.2//EN"
2348 uri="http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd"/&gt;
2349...</pre>
2350
2351<p>This is the beginning of a catalog for DocBook 4.1.2, XML Catalogs are
2352written in XML, there is a specific namespace for catalog elements
2353"urn:oasis:names:tc:entity:xmlns:xml:catalog". The first entry in this
2354catalog is a <code>public</code> mapping it allows to associate a Public
2355Identifier with an URI.</p>
2356<pre>...
2357 &lt;rewriteSystem systemIdStartString="http://www.oasis-open.org/docbook/"
2358 rewritePrefix="file:///usr/share/xml/docbook/"/&gt;
2359...</pre>
2360
2361<p>A <code>rewriteSystem</code> is a very powerful instruction, it says that
2362any URI starting with a given prefix should be looked at another URI
2363constructed by replacing the prefix with an new one. In effect this acts like
2364a cache system for a full area of the Web. In practice it is extremely useful
2365with a file prefix if you have installed a copy of those resources on your
2366local system.</p>
2367<pre>...
2368&lt;delegatePublic publicIdStartString="-//OASIS//DTD XML Catalog //"
2369 catalog="file:///usr/share/xml/docbook.xml"/&gt;
2370&lt;delegatePublic publicIdStartString="-//OASIS//ENTITIES DocBook XML"
2371 catalog="file:///usr/share/xml/docbook.xml"/&gt;
2372&lt;delegatePublic publicIdStartString="-//OASIS//DTD DocBook XML"
2373 catalog="file:///usr/share/xml/docbook.xml"/&gt;
2374&lt;delegateSystem systemIdStartString="http://www.oasis-open.org/docbook/"
2375 catalog="file:///usr/share/xml/docbook.xml"/&gt;
2376&lt;delegateURI uriStartString="http://www.oasis-open.org/docbook/"
2377 catalog="file:///usr/share/xml/docbook.xml"/&gt;
2378...</pre>
2379
2380<p>Delegation is the core features which allows to build a tree of catalogs,
2381easier to maintain than a single catalog, based on Public Identifier, System
2382Identifier or URI prefixes it instructs the catalog software to look up
2383entries in another resource. This feature allow to build hierarchies of
2384catalogs, the set of entries presented should be sufficient to redirect the
2385resolution of all DocBook references to the specific catalog in
2386<code>/usr/share/xml/docbook.xml</code> this one in turn could delegate all
2387references for DocBook 4.2.1 to a specific catalog installed at the same time
2388as the DocBook resources on the local machine.</p>
2389
2390<h3><a name="reference">How to tune catalog usage:</a></h3>
2391
2392<p>The user can change the default catalog behaviour by redirecting queries
2393to its own set of catalogs, this can be done by setting the
2394<code>XML_CATALOG_FILES</code> environment variable to a list of catalogs, an
2395empty one should deactivate loading the default <code>/etc/xml/catalog</code>
2396default catalog</p>
2397
2398<h3><a name="validate">How to debug catalog processing:</a></h3>
2399
2400<p>Setting up the <code>XML_DEBUG_CATALOG</code> environment variable will
2401make libxml output debugging informations for each catalog operations, for
2402example:</p>
2403<pre>orchis:~/XML -&gt; xmllint --memory --noout test/ent2
2404warning: failed to load external entity "title.xml"
2405orchis:~/XML -&gt; export XML_DEBUG_CATALOG=
2406orchis:~/XML -&gt; xmllint --memory --noout test/ent2
2407Failed to parse catalog /etc/xml/catalog
2408Failed to parse catalog /etc/xml/catalog
2409warning: failed to load external entity "title.xml"
2410Catalogs cleanup
2411orchis:~/XML -&gt; </pre>
2412
2413<p>The test/ent2 references an entity, running the parser from memory makes
2414the base URI unavailable and the the "title.xml" entity cannot be loaded.
2415Setting up the debug environment variable allows to detect that an attempt is
2416made to load the <code>/etc/xml/catalog</code> but since it's not present the
2417resolution fails.</p>
2418
2419<p>But the most advanced way to debug XML catalog processing is to use the
2420<strong>xmlcatalog</strong> command shipped with libxml2, it allows to load
2421catalogs and make resolution queries to see what is going on. This is also
2422used for the regression tests:</p>
2423<pre>orchis:~/XML -&gt; ./xmlcatalog test/catalogs/docbook.xml \
2424 "-//OASIS//DTD DocBook XML V4.1.2//EN"
2425http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd
2426orchis:~/XML -&gt; </pre>
2427
2428<p>For debugging what is going on, adding one -v flags increase the verbosity
2429level to indicate the processing done (adding a second flag also indicate
2430what elements are recognized at parsing):</p>
2431<pre>orchis:~/XML -&gt; ./xmlcatalog -v test/catalogs/docbook.xml \
2432 "-//OASIS//DTD DocBook XML V4.1.2//EN"
2433Parsing catalog test/catalogs/docbook.xml's content
2434Found public match -//OASIS//DTD DocBook XML V4.1.2//EN
2435http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd
2436Catalogs cleanup
2437orchis:~/XML -&gt; </pre>
2438
2439<p>A shell interface is also available to debug and process multiple queries
2440(and for regression tests):</p>
2441<pre>orchis:~/XML -&gt; ./xmlcatalog -shell test/catalogs/docbook.xml \
2442 "-//OASIS//DTD DocBook XML V4.1.2//EN"
2443&gt; help
2444Commands available:
2445public PublicID: make a PUBLIC identifier lookup
2446system SystemID: make a SYSTEM identifier lookup
2447resolve PublicID SystemID: do a full resolver lookup
2448add 'type' 'orig' 'replace' : add an entry
2449del 'values' : remove values
2450dump: print the current catalog state
2451debug: increase the verbosity level
2452quiet: decrease the verbosity level
2453exit: quit the shell
2454&gt; public "-//OASIS//DTD DocBook XML V4.1.2//EN"
2455http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd
2456&gt; quit
2457orchis:~/XML -&gt; </pre>
2458
2459<p>This should be sufficient for most debugging purpose, this was actually
2460used heavily to debug the XML Catalog implementation itself.</p>
2461
2462<h3><a name="Declaring">How to create and maintain</a> catalogs:</h3>
2463
2464<p>Basically XML Catalogs are XML files, you can either use XML tools to
2465manage them or use <strong>xmlcatalog</strong> for this. The basic step is
2466to create a catalog the -create option provide this facility:</p>
2467<pre>orchis:~/XML -&gt; ./xmlcatalog --create tst.xml
2468&lt;?xml version="1.0"?&gt;
2469&lt;!DOCTYPE catalog PUBLIC "-//OASIS//DTD Entity Resolution XML Catalog V1.0//EN"
2470 "http://www.oasis-open.org/committees/entity/release/1.0/catalog.dtd"&gt;
2471&lt;catalog xmlns="urn:oasis:names:tc:entity:xmlns:xml:catalog"/&gt;
2472orchis:~/XML -&gt; </pre>
2473
2474<p>By default xmlcatalog does not overwrite the original catalog and save the
2475result on the standard output, this can be overridden using the -noout
2476option. The <code>-add</code> command allows to add entries in the
2477catalog:</p>
2478<pre>orchis:~/XML -&gt; ./xmlcatalog --noout --create --add "public" \
2479 "-//OASIS//DTD DocBook XML V4.1.2//EN" \
2480 http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd tst.xml
2481orchis:~/XML -&gt; cat tst.xml
2482&lt;?xml version="1.0"?&gt;
2483&lt;!DOCTYPE catalog PUBLIC "-//OASIS//DTD Entity Resolution XML Catalog V1.0//EN" \
2484 "http://www.oasis-open.org/committees/entity/release/1.0/catalog.dtd"&gt;
2485&lt;catalog xmlns="urn:oasis:names:tc:entity:xmlns:xml:catalog"&gt;
2486&lt;public publicId="-//OASIS//DTD DocBook XML V4.1.2//EN"
2487 uri="http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd"/&gt;
2488&lt;/catalog&gt;
2489orchis:~/XML -&gt; </pre>
2490
2491<p>The <code>-add</code> option will always take 3 parameters even if some of
2492the XML Catalog constructs (like nextCatalog) will have only a single
2493argument, just pass a third empty string, it will be ignored.</p>
2494
2495<p>Similarly the <code>-del</code> option remove matching entries from the
2496catalog:</p>
2497<pre>orchis:~/XML -&gt; ./xmlcatalog --del \
2498 "http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd" tst.xml
2499&lt;?xml version="1.0"?&gt;
2500&lt;!DOCTYPE catalog PUBLIC "-//OASIS//DTD Entity Resolution XML Catalog V1.0//EN"
2501 "http://www.oasis-open.org/committees/entity/release/1.0/catalog.dtd"&gt;
2502&lt;catalog xmlns="urn:oasis:names:tc:entity:xmlns:xml:catalog"/&gt;
2503orchis:~/XML -&gt; </pre>
2504
2505<p>The catalog is now empty. Note that the matching of <code>-del</code> is
2506exact and would have worked in a similar fashion with the Public ID
2507string.</p>
2508
2509<p>This is rudimentary but should be sufficient to manage a not too complex
2510catalog tree of resources.</p>
2511
2512<h3><a name="implemento">The implementor corner quick review of the
2513API:</a></h3>
2514
2515<p>First, and like for every other module of libxml, there is an
2516automatically generated <a href="html/libxml-catalog.html">API page for
2517catalog support</a>.</p>
2518
2519<p>The header for the catalog interfaces should be included as:</p>
2520<pre>#include &lt;libxml/catalog.h&gt;</pre>
2521
2522<p>The API is voluntarily kept very simple. First it is not obvious that
2523applications really need access to it since it is the default behaviour of
2524libxml (Note: it is possible to completely override libxml default catalog by
2525using <a href="html/libxml-parser.html">xmlSetExternalEntityLoader</a> to
2526plug an application specific resolver).</p>
2527
2528<p>Basically libxml support 2 catalog lists:</p>
2529<ul>
2530 <li>the default one, global shared by all the application</li>
2531 <li>a per-document catalog, this one is built if the document uses the
2532 <code>oasis-xml-catalog</code> PIs to specify its own catalog list, it is
2533 associated to the parser context and destroyed when the parsing context
2534 is destroyed.</li>
2535</ul>
2536
2537<p>the document one will be used first if it exists.</p>
2538
2539<h4>Initialization routines:</h4>
2540
2541<p>xmlInitializeCatalog(), xmlLoadCatalog() and xmlLoadCatalogs() should be
2542used at startup to initialize the catalog, if the catalog should be
2543initialized with specific values xmlLoadCatalog() or xmlLoadCatalogs()
2544should be called before xmlInitializeCatalog() which would otherwise do a
2545default initialization first.</p>
2546
2547<p>The xmlCatalogAddLocal() call is used by the parser to grow the document
2548own catalog list if needed.</p>
2549
2550<h4>Preferences setup:</h4>
2551
2552<p>The XML Catalog spec requires the possibility to select default
2553preferences between public and system delegation,
2554xmlCatalogSetDefaultPrefer() allows this, xmlCatalogSetDefaults() and
2555xmlCatalogGetDefaults() allow to control if XML Catalogs resolution should
2556be forbidden, allowed for global catalog, for document catalog or both, the
2557default is to allow both.</p>
2558
2559<p>And of course xmlCatalogSetDebug() allows to generate debug messages
2560(through the xmlGenericError() mechanism).</p>
2561
2562<h4>Querying routines:</h4>
2563
2564<p>xmlCatalogResolve(), xmlCatalogResolveSystem(), xmlCatalogResolvePublic()
2565and xmlCatalogResolveURI() are relatively explicit if you read the XML
2566Catalog specification they correspond to section 7 algorithms, they should
2567also work if you have loaded an SGML catalog with a simplified semantic.</p>
2568
2569<p>xmlCatalogLocalResolve() and xmlCatalogLocalResolveURI() are the same but
2570operate on the document catalog list</p>
2571
2572<h4>Cleanup and Miscellaneous:</h4>
2573
2574<p>xmlCatalogCleanup() free-up the global catalog, xmlCatalogFreeLocal() is
2575the per-document equivalent.</p>
2576
2577<p>xmlCatalogAdd() and xmlCatalogRemove() are used to dynamically modify the
2578first catalog in the global list, and xmlCatalogDump() allows to dump a
2579catalog state, those routines are primarily designed for xmlcatalog, I'm not
2580sure that exposing more complex interfaces (like navigation ones) would be
2581really useful.</p>
2582
2583<p>The xmlParseCatalogFile() is a function used to load XML Catalog files,
2584it's similar as xmlParseFile() except it bypass all catalog lookups, it's
2585provided because this functionality may be useful for client tools.</p>
2586
2587<h4>threaded environments:</h4>
2588
2589<p>Since the catalog tree is built progressively, some care has been taken to
2590try to avoid troubles in multithreaded environments. The code is now thread
2591safe assuming that the libxml library has been compiled with threads
2592support.</p>
2593
2594<p></p>
2595
2596<h3><a name="Other">Other resources</a></h3>
2597
2598<p>The XML Catalog specification is relatively recent so there isn't much
2599literature to point at:</p>
2600<ul>
2601 <li>You can find an good rant from Norm Walsh about <a
2602 href="http://www.arbortext.com/Think_Tank/XML_Resources/Issue_Three/issue_three.html">the
2603 need for catalogs</a>, it provides a lot of context informations even if
2604 I don't agree with everything presented.</li>
2605 <li>An <a href="http://home.ccil.org/~cowan/XML/XCatalog.html">old XML
2606 catalog proposal</a> from John Cowan</li>
2607 <li>The <a href="http://www.rddl.org/">Resource Directory Description
2608 Language</a> (RDDL) another catalog system but more oriented toward
2609 providing metadata for XML namespaces.</li>
2610 <li>the page from the OASIS Technical <a
2611 href="http://www.oasis-open.org/committees/entity/">Committee on Entity
2612 Resolution</a> who maintains XML Catalog, you will find pointers to the
2613 specification update, some background and pointers to others tools
2614 providing XML Catalog support</li>
Daniel Veillard35e937a2002-01-19 22:21:54 +0000[diff] [blame]2615 <li>Here is a <a href="buildDocBookCatalog">shell script</a> to generate
2616 XML Catalogs for DocBook 4.1.2 . If it can write to the /etc/xml/
2617 directory, it will set-up /etc/xml/catalog and /etc/xml/docbook based on
2618 the resources found on the system. Otherwise it will just create
2619 ~/xmlcatalog and ~/dbkxmlcatalog and doing:
Daniel Veillardc575b992002-02-08 13:28:40 +0000[diff] [blame]2620 <p><code>export XMLCATALOG=$HOME/xmlcatalog</code></p>
Daniel Veillard35e937a2002-01-19 22:21:54 +0000[diff] [blame]2621 <p>should allow to process DocBook documentations without requiring
2622 network accesses for the DTd or stylesheets</p>
2623 </li>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2624 <li>I have uploaded <a href="ftp://xmlsoft.org/test/dbk412catalog.tar.gz">a
Daniel Veillard35e937a2002-01-19 22:21:54 +0000[diff] [blame]2625 small tarball</a> containing XML Catalogs for DocBook 4.1.2 which seems
2626 to work fine for me too</li>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2627 <li>The <a href="http://www.xmlsoft.org/xmlcatalog_man.html">xmlcatalog
2628 manual page</a></li>
2629</ul>
2630
2631<p>If you have suggestions for corrections or additions, simply contact
2632me:</p>
2633
2634<h2><a name="library">The parser interfaces</a></h2>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]2635
2636<p>This section is directly intended to help programmers getting bootstrapped
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]2637using the XML library from the C language. It is not intended to be
2638extensive. I hope the automatically generated documents will provide the
2639completeness required, but as a separate set of documents. The interfaces of
2640the XML library are by principle low level, there is nearly zero abstraction.
2641Those interested in a higher level API should <a href="#DOM">look at
2642DOM</a>.</p>
Daniel Veillardccb09631998-10-27 06:21:04 +0000[diff] [blame]2643
Daniel Veillard9cb5ff42001-01-29 08:22:21 +0000[diff] [blame]2644<p>The <a href="html/libxml-parser.html">parser interfaces for XML</a> are
2645separated from the <a href="html/libxml-htmlparser.html">HTML parser
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]2646interfaces</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]2647
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]2648<h3><a name="Invoking">Invoking the parser : the pull method</a></h3>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]2649
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]2650<p>Usually, the first thing to do is to read an XML input. The parser accepts
2651documents either from in-memory strings or from files. The functions are
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]2652defined in "parser.h":</p>
Daniel Veillard10c6a8f1998-10-28 01:00:12 +0000[diff] [blame]2653<dl>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]2654 <dt><code>xmlDocPtr xmlParseMemory(char *buffer, int size);</code></dt>
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]2655 <dd><p>Parse a null-terminated string containing the document.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]2656 </dd>
Daniel Veillard10c6a8f1998-10-28 01:00:12 +0000[diff] [blame]2657</dl>
2658<dl>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]2659 <dt><code>xmlDocPtr xmlParseFile(const char *filename);</code></dt>
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]2660 <dd><p>Parse an XML document contained in a (possibly compressed)
2661 file.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]2662 </dd>
Daniel Veillard10c6a8f1998-10-28 01:00:12 +0000[diff] [blame]2663</dl>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]2664
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]2665<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]2666failure).</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]2667
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]2668<h3 id="Invoking1">Invoking the parser: the push method</h3>
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]2669
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]2670<p>In order for the application to keep the control when the document is
2671being fetched (which is common for GUI based programs) libxml provides a push
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]2672interface, too, as of version 1.8.3. Here are the interface functions:</p>
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]2673<pre>xmlParserCtxtPtr xmlCreatePushParserCtxt(xmlSAXHandlerPtr sax,
2674 void *user_data,
2675 const char *chunk,
2676 int size,
2677 const char *filename);
2678int xmlParseChunk (xmlParserCtxtPtr ctxt,
2679 const char *chunk,
2680 int size,
2681 int terminate);</pre>
2682
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]2683<p>and here is a simple example showing how to use the interface:</p>
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]2684<pre> FILE *f;
2685
2686 f = fopen(filename, "r");
2687 if (f != NULL) {
2688 int res, size = 1024;
2689 char chars[1024];
2690 xmlParserCtxtPtr ctxt;
2691
2692 res = fread(chars, 1, 4, f);
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]2693 if (res &gt; 0) {
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]2694 ctxt = xmlCreatePushParserCtxt(NULL, NULL,
2695 chars, res, filename);
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]2696 while ((res = fread(chars, 1, size, f)) &gt; 0) {
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]2697 xmlParseChunk(ctxt, chars, res, 0);
2698 }
2699 xmlParseChunk(ctxt, chars, 0, 1);
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]2700 doc = ctxt-&gt;myDoc;
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]2701 xmlFreeParserCtxt(ctxt);
2702 }
2703 }</pre>
2704
Daniel Veillardec70e912001-02-26 20:10:45 +0000[diff] [blame]2705<p>The HTML parser embedded into libxml also has a push interface; the
2706functions are just prefixed by "html" rather than "xml".</p>
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]2707
2708<h3 id="Invoking2">Invoking the parser: the SAX interface</h3>
2709
Daniel Veillardec70e912001-02-26 20:10:45 +0000[diff] [blame]2710<p>The tree-building interface makes the parser memory-hungry, first loading
2711the document in memory and then building the tree itself. Reading a document
2712without building the tree is possible using the SAX interfaces (see SAX.h and
2713<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]2714Henstridge's documentation</a>). Note also that the push interface can be
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]2715limited to SAX: just use the two first arguments of
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]2716<code>xmlCreatePushParserCtxt()</code>.</p>
Daniel Veillardccb09631998-10-27 06:21:04 +0000[diff] [blame]2717
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]2718<h3><a name="Building">Building a tree from scratch</a></h3>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]2719
2720<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]2721there is a set of functions dedicated to building new elements. (These are
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]2722also described in &lt;libxml/tree.h&gt;.) For example, here is a piece of
2723code that produces the XML document used in the previous examples:</p>
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]2724<pre> #include &lt;libxml/tree.h&gt;
Daniel Veillard361d8452000-04-03 19:48:13 +0000[diff] [blame]2725 xmlDocPtr doc;
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]2726 xmlNodePtr tree, subtree;
2727
2728 doc = xmlNewDoc("1.0");
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]2729 doc-&gt;children = xmlNewDocNode(doc, NULL, "EXAMPLE", NULL);
2730 xmlSetProp(doc-&gt;children, "prop1", "gnome is great");
2731 xmlSetProp(doc-&gt;children, "prop2", "&amp; linux too");
2732 tree = xmlNewChild(doc-&gt;children, NULL, "head", NULL);
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]2733 subtree = xmlNewChild(tree, NULL, "title", "Welcome to Gnome");
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]2734 tree = xmlNewChild(doc-&gt;children, NULL, "chapter", NULL);
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]2735 subtree = xmlNewChild(tree, NULL, "title", "The Linux adventure");
2736 subtree = xmlNewChild(tree, NULL, "p", "bla bla bla ...");
2737 subtree = xmlNewChild(tree, NULL, "image", NULL);
2738 xmlSetProp(subtree, "href", "linus.gif");</pre>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]2739
2740<p>Not really rocket science ...</p>
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]2741
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]2742<h3><a name="Traversing">Traversing the tree</a></h3>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]2743
Daniel Veillard9cb5ff42001-01-29 08:22:21 +0000[diff] [blame]2744<p>Basically by <a href="html/libxml-tree.html">including "tree.h"</a> your
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]2745code has access to the internal structure of all the elements of the tree.
2746The names should be somewhat simple like <strong>parent</strong>,
Daniel Veillard306be992000-07-03 12:38:45 +0000[diff] [blame]2747<strong>children</strong>, <strong>next</strong>, <strong>prev</strong>,
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]2748<strong>properties</strong>, etc... For example, still with the previous
Daniel Veillard0142b842000-01-14 14:45:24 +0000[diff] [blame]2749example:</p>
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]2750<pre><code>doc-&gt;children-&gt;children-&gt;children</code></pre>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]2751
2752<p>points to the title element,</p>
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]2753<pre>doc-&gt;children-&gt;children-&gt;next-&gt;children-&gt;children</pre>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]2754
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]2755<p>points to the text node containing the chapter title "The Linux
2756adventure".</p>
Daniel Veillard10c6a8f1998-10-28 01:00:12 +0000[diff] [blame]2757
Daniel Veillardb24054a1999-12-18 15:32:46 +0000[diff] [blame]2758<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]2759present before the document root, so <code>doc-&gt;children</code> may point
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]2760to an element which is not the document Root Element; a function
Daniel Veillard5cb5ab81999-12-21 15:35:29 +0000[diff] [blame]2761<code>xmlDocGetRootElement()</code> was added for this purpose.</p>
Daniel Veillardb24054a1999-12-18 15:32:46 +0000[diff] [blame]2762
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]2763<h3><a name="Modifying">Modifying the tree</a></h3>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]2764
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]2765<p>Functions are provided for reading and writing the document content. Here
Daniel Veillard9cb5ff42001-01-29 08:22:21 +0000[diff] [blame]2766is an excerpt from the <a href="html/libxml-tree.html">tree API</a>:</p>
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]2767<dl>
Daniel Veillarddd6b3671999-09-23 22:19:22 +0000[diff] [blame]2768 <dt><code>xmlAttrPtr xmlSetProp(xmlNodePtr node, const xmlChar *name, const
2769 xmlChar *value);</code></dt>
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]2770 <dd><p>This sets (or changes) an attribute carried by an ELEMENT node.
2771 The value can be NULL.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]2772 </dd>
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]2773</dl>
2774<dl>
Daniel Veillarddd6b3671999-09-23 22:19:22 +0000[diff] [blame]2775 <dt><code>const xmlChar *xmlGetProp(xmlNodePtr node, const xmlChar
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]2776 *name);</code></dt>
Daniel Veillardc92c3042000-09-29 02:42:04 +0000[diff] [blame]2777 <dd><p>This function returns a pointer to new copy of the property
2778 content. Note that the user must deallocate the result.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]2779 </dd>
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]2780</dl>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]2781
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]2782<p>Two functions are provided for reading and writing the text associated
2783with elements:</p>
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]2784<dl>
Daniel Veillarddd6b3671999-09-23 22:19:22 +0000[diff] [blame]2785 <dt><code>xmlNodePtr xmlStringGetNodeList(xmlDocPtr doc, const xmlChar
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]2786 *value);</code></dt>
Daniel Veillardec70e912001-02-26 20:10:45 +0000[diff] [blame]2787 <dd><p>This function takes an "external" string and converts it to one
2788 text node or possibly to a list of entity and text nodes. All
2789 non-predefined entity references like &amp;Gnome; will be stored
2790 internally as entity nodes, hence the result of the function may not be
2791 a single node.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]2792 </dd>
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]2793</dl>
2794<dl>
Daniel Veillarddd6b3671999-09-23 22:19:22 +0000[diff] [blame]2795 <dt><code>xmlChar *xmlNodeListGetString(xmlDocPtr doc, xmlNodePtr list, int
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]2796 inLine);</code></dt>
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]2797 <dd><p>This function is the inverse of
2798 <code>xmlStringGetNodeList()</code>. It generates a new string
2799 containing the content of the text and entity nodes. Note the extra
2800 argument inLine. If this argument is set to 1, the function will expand
2801 entity references. For example, instead of returning the &amp;Gnome;
2802 XML encoding in the string, it will substitute it with its value (say,
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]2803 "GNU Network Object Model Environment").</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]2804 </dd>
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]2805</dl>
Daniel Veillard10c6a8f1998-10-28 01:00:12 +0000[diff] [blame]2806
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]2807<h3><a name="Saving">Saving a tree</a></h3>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]2808
2809<p>Basically 3 options are possible:</p>
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]2810<dl>
Daniel Veillarddd6b3671999-09-23 22:19:22 +0000[diff] [blame]2811 <dt><code>void xmlDocDumpMemory(xmlDocPtr cur, xmlChar**mem, int
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]2812 *size);</code></dt>
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]2813 <dd><p>Returns a buffer into which the document has been saved.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]2814 </dd>
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]2815</dl>
2816<dl>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]2817 <dt><code>extern void xmlDocDump(FILE *f, xmlDocPtr doc);</code></dt>
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]2818 <dd><p>Dumps a document to an open file descriptor.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]2819 </dd>
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]2820</dl>
2821<dl>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]2822 <dt><code>int xmlSaveFile(const char *filename, xmlDocPtr cur);</code></dt>
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]2823 <dd><p>Saves the document to a file. In this case, the compression
2824 interface is triggered if it has been turned on.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]2825 </dd>
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]2826</dl>
Daniel Veillard10c6a8f1998-10-28 01:00:12 +0000[diff] [blame]2827
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]2828<h3><a name="Compressio">Compression</a></h3>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]2829
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]2830<p>The library transparently handles compression when doing file-based
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]2831accesses. The level of compression on saves can be turned on either globally
2832or individually for one file:</p>
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]2833<dl>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]2834 <dt><code>int xmlGetDocCompressMode (xmlDocPtr doc);</code></dt>
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]2835 <dd><p>Gets the document compression ratio (0-9).</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]2836 </dd>
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]2837</dl>
2838<dl>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]2839 <dt><code>void xmlSetDocCompressMode (xmlDocPtr doc, int mode);</code></dt>
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]2840 <dd><p>Sets the document compression ratio.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]2841 </dd>
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]2842</dl>
2843<dl>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]2844 <dt><code>int xmlGetCompressMode(void);</code></dt>
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]2845 <dd><p>Gets the default compression ratio.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]2846 </dd>
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]2847</dl>
2848<dl>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]2849 <dt><code>void xmlSetCompressMode(int mode);</code></dt>
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]2850 <dd><p>Sets the default compression ratio.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]2851 </dd>
Daniel Veillard25940b71998-10-29 05:51:30 +0000[diff] [blame]2852</dl>
2853
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]2854<h2><a name="Entities">Entities or no entities</a></h2>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]2855
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]2856<p>Entities in principle are similar to simple C macros. An entity defines an
2857abbreviation for a given string that you can reuse many times throughout the
2858content of your document. Entities are especially useful when a given string
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]2859may occur frequently within a document, or to confine the change needed to a
2860document to a restricted area in the internal subset of the document (at the
2861beginning). Example:</p>
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]2862<pre>1 &lt;?xml version="1.0"?&gt;
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]28632 &lt;!DOCTYPE EXAMPLE SYSTEM "example.dtd" [
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]28643 &lt;!ENTITY xml "Extensible Markup Language"&gt;
28654 ]&gt;
28665 &lt;EXAMPLE&gt;
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]28676 &amp;xml;
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]28687 &lt;/EXAMPLE&gt;</pre>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]2869
2870<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]2871its name with '&amp;' and following it by ';' without any spaces added. There
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]2872are 5 predefined entities in libxml allowing you to escape charaters with
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]2873predefined meaning in some parts of the xml document content:
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]2874<strong>&amp;lt;</strong> for the character '&lt;', <strong>&amp;gt;</strong>
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]2875for the character '&gt;', <strong>&amp;apos;</strong> for the character ''',
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]2876<strong>&amp;quot;</strong> for the character '"', and
2877<strong>&amp;amp;</strong> for the character '&amp;'.</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]2878
2879<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]2880substitute an entity's content so that you can see the replacement text in
2881your application. Or you may prefer to keep entity references as such in the
2882content to be able to save the document back without losing this usually
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]2883precious information (if the user went through the pain of explicitly
2884defining entities, he may have a a rather negative attitude if you blindly
2885susbtitute them as saving time). The <a
Daniel Veillard9cb5ff42001-01-29 08:22:21 +0000[diff] [blame]2886href="html/libxml-parser.html#XMLSUBSTITUTEENTITIESDEFAULT">xmlSubstituteEntitiesDefault()</a>
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]2887function allows you to check and change the behaviour, which is to not
2888substitute entities by default.</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]2889
2890<p>Here is the DOM tree built by libxml for the previous document in the
2891default case:</p>
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]2892<pre>/gnome/src/gnome-xml -&gt; ./xmllint --debug test/ent1
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]2893DOCUMENT
2894version=1.0
2895 ELEMENT EXAMPLE
2896 TEXT
2897 content=
2898 ENTITY_REF
2899 INTERNAL_GENERAL_ENTITY xml
2900 content=Extensible Markup Language
2901 TEXT
2902 content=</pre>
2903
2904<p>And here is the result when substituting entities:</p>
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]2905<pre>/gnome/src/gnome-xml -&gt; ./tester --debug --noent test/ent1
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]2906DOCUMENT
2907version=1.0
2908 ELEMENT EXAMPLE
2909 TEXT
2910 content= Extensible Markup Language</pre>
2911
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]2912<p>So, entities or no entities? Basically, it depends on your use case. I
2913suggest that you keep the non-substituting default behaviour and avoid using
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]2914entities in your XML document or data if you are not willing to handle the
2915entity references elements in the DOM tree.</p>
2916
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]2917<p>Note that at save time libxml enforces the conversion of the predefined
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]2918entities where necessary to prevent well-formedness problems, and will also
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]2919transparently replace those with chars (i.e. it will not generate entity
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]2920reference elements in the DOM tree or call the reference() SAX callback when
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]2921finding them in the input).</p>
2922
Daniel Veillard7b9c4b72000-08-25 16:26:50 +0000[diff] [blame]2923<p><span style="background-color: #FF0000">WARNING</span>: handling entities
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]2924on top of the libxml SAX interface is difficult!!! If you plan to use
Daniel Veillard7b9c4b72000-08-25 16:26:50 +0000[diff] [blame]2925non-predefined entities in your documents, then the learning cuvre to handle
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]2926then 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]2927strongly suggest you consider using the DOM interface instead and let libxml
Daniel Veillard8c6d6af2000-08-25 17:14:13 +0000[diff] [blame]2928deal with the complexity rather than trying to do it yourself.</p>
Daniel Veillard7b9c4b72000-08-25 16:26:50 +0000[diff] [blame]2929
Daniel Veillard2f4dfc41999-09-24 14:03:48 +0000[diff] [blame]2930<h2><a name="Namespaces">Namespaces</a></h2>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]2931
Daniel Veillardec303412000-03-24 13:41:54 +0000[diff] [blame]2932<p>The libxml library implements <a
2933href="http://www.w3.org/TR/REC-xml-names/">XML namespaces</a> support by
2934recognizing namespace contructs in the input, and does namespace lookup
2935automatically when building the DOM tree. A namespace declaration is
2936associated with an in-memory structure and all elements or attributes within
2937that namespace point to it. Hence testing the namespace is a simple and fast
2938equality operation at the user level.</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]2939
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]2940<p>I suggest that people using libxml use a namespace, and declare it in the
2941root element of their document as the default namespace. Then they don't need
2942to 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]2943refinement and merging of data from different sources. This doesn't increase
Daniel Veillardec70e912001-02-26 20:10:45 +0000[diff] [blame]2944the size of the XML output significantly, but significantly increases its
2945value in the long-term. Example:</p>
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]2946<pre>&lt;mydoc xmlns="http://mydoc.example.org/schemas/"&gt;
2947 &lt;elem1&gt;...&lt;/elem1&gt;
2948 &lt;elem2&gt;...&lt;/elem2&gt;
2949&lt;/mydoc&gt;</pre>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]2950
Daniel Veillardec70e912001-02-26 20:10:45 +0000[diff] [blame]2951<p>The namespace value has to be an absolute URL, but the URL doesn't have to
2952point to any existing resource on the Web. It will bind all the element and
2953atributes with that URL. I suggest to use an URL within a domain you control,
2954and that the URL should contain some kind of version information if possible.
2955For example, <code>"http://www.gnome.org/gnumeric/1.0/"</code> is a good
2956namespace scheme.</p>
Daniel Veillardec303412000-03-24 13:41:54 +0000[diff] [blame]2957
2958<p>Then when you load a file, make sure that a namespace carrying the
Daniel Veillard88f00ae2000-03-02 00:15:55 +0000[diff] [blame]2959version-independent prefix is installed on the root element of your document,
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]2960and if the version information don't match something you know, warn the user
2961and 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]2962namespace checking on the prefix value. &lt;foo:text&gt; may be exactly the
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]2963same as &lt;bar:text&gt; in another document. What really matters is the URI
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]2964associated with the element or the attribute, not the prefix string (which is
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]2965just a shortcut for the full URI). In libxml, element and attributes have an
Daniel Veillardec303412000-03-24 13:41:54 +0000[diff] [blame]2966<code>ns</code> field pointing to an xmlNs structure detailing the namespace
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]2967prefix and its URI.</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]2968
2969<p>@@Interfaces@@</p>
2970
2971<p>@@Examples@@</p>
2972
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]2973<p>Usually people object to using namespaces together with validity checking.
2974I will try to make sure that using namespaces won't break validity checking,
2975so even if you plan to use or currently are using validation I strongly
Daniel Veillardf13e1ed2000-03-06 07:41:49 +0000[diff] [blame]2976suggest adding namespaces to your document. A default namespace scheme
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]2977<code>xmlns="http://...."</code> should not break validity even on less
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]2978flexible parsers. Using namespaces to mix and differentiate content coming
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]2979from multiple DTDs will certainly break current validation schemes. I will
2980try to provide ways to do this, but this may not be portable or
2981standardized.</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]2982
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2983<h2><a name="Upgrading">Upgrading 1.x code</a></h2>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]2984
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2985<p>Incompatible changes:</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]2986
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]2987<p>Version 2 of libxml is the first version introducing serious backward
2988incompatible changes. The main goals were:</p>
2989<ul>
2990 <li>a general cleanup. A number of mistakes inherited from the very early
2991 versions couldn't be changed due to compatibility constraints. Example
2992 the "childs" element in the nodes.</li>
2993 <li>Uniformization of the various nodes, at least for their header and link
2994 parts (doc, parent, children, prev, next), the goal is a simpler
2995 programming model and simplifying the task of the DOM implementors.</li>
2996 <li>better conformances to the XML specification, for example version 1.x
2997 had an heuristic to try to detect ignorable white spaces. As a result the
2998 SAX event generated were ignorableWhitespace() while the spec requires
2999 character() in that case. This also mean that a number of DOM node
3000 containing blank text may populate the DOM tree which were not present
3001 before.</li>
3002</ul>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]3003
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]3004<h3>How to fix libxml-1.x code:</h3>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]3005
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]3006<p>So client code of libxml designed to run with version 1.x may have to be
3007changed to compile against version 2.x of libxml. Here is a list of changes
3008that I have collected, they may not be sufficient, so in case you find other
3009change which are required, <a href="mailto:Daniel.Ïeillardw3.org">drop me a
3010mail</a>:</p>
3011<ol>
3012 <li>The package name have changed from libxml to libxml2, the library name
3013 is now -lxml2 . There is a new xml2-config script which should be used to
3014 select the right parameters libxml2</li>
3015 <li>Node <strong>childs</strong> field has been renamed
3016 <strong>children</strong> so s/childs/children/g should be applied
3017 (probablility of having "childs" anywere else is close to 0+</li>
3018 <li>The document don't have anymore a <strong>root</strong> element it has
3019 been replaced by <strong>children</strong> and usually you will get a
3020 list of element here. For example a Dtd element for the internal subset
3021 and it's declaration may be found in that list, as well as processing
3022 instructions or comments found before or after the document root element.
3023 Use <strong>xmlDocGetRootElement(doc)</strong> to get the root element of
3024 a document. Alternatively if you are sure to not reference Dtds nor have
3025 PIs or comments before or after the root element
3026 s/-&gt;root/-&gt;children/g will probably do it.</li>
3027 <li>The white space issue, this one is more complex, unless special case of
3028 validating parsing, the line breaks and spaces usually used for indenting
3029 and formatting the document content becomes significant. So they are
3030 reported by SAX and if your using the DOM tree, corresponding nodes are
3031 generated. Too approach can be taken:
3032 <ol>
3033 <li>lazy one, use the compatibility call
3034 <strong>xmlKeepBlanksDefault(0)</strong> but be aware that you are
3035 relying on a special (and possibly broken) set of heuristics of
3036 libxml to detect ignorable blanks. Don't complain if it breaks or
3037 make your application not 100% clean w.r.t. to it's input.</li>
3038 <li>the Right Way: change you code to accept possibly unsignificant
3039 blanks characters, or have your tree populated with weird blank text
3040 nodes. You can spot them using the comodity function
3041 <strong>xmlIsBlankNode(node)</strong> returning 1 for such blank
3042 nodes.</li>
3043 </ol>
3044 <p>Note also that with the new default the output functions don't add any
3045 extra indentation when saving a tree in order to be able to round trip
3046 (read and save) without inflating the document with extra formatting
3047 chars.</p>
3048 </li>
3049 <li>The include path has changed to $prefix/libxml/ and the includes
3050 themselves uses this new prefix in includes instructions... If you are
3051 using (as expected) the
3052 <pre>xml2-config --cflags</pre>
3053 <p>output to generate you compile commands this will probably work out of
3054 the box</p>
3055 </li>
3056 <li>xmlDetectCharEncoding takes an extra argument indicating the lenght in
3057 byte of the head of the document available for character detection.</li>
3058</ol>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]3059
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]3060<h3>Ensuring both libxml-1.x and libxml-2.x compatibility</h3>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]3061
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]3062<p>Two new version of libxml (1.8.11) and libxml2 (2.3.4) have been released
3063to allow smoth upgrade of existing libxml v1code while retaining
3064compatibility. They offers the following:</p>
3065<ol>
3066 <li>similar include naming, one should use
3067 <strong>#include&lt;libxml/...&gt;</strong> in both cases.</li>
3068 <li>similar identifiers defined via macros for the child and root fields:
3069 respectively <strong>xmlChildrenNode</strong> and
3070 <strong>xmlRootNode</strong></li>
3071 <li>a new macro <strong>LIBXML_TEST_VERSION</strong> which should be
3072 inserted once in the client code</li>
3073</ol>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]3074
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]3075<p>So the roadmap to upgrade your existing libxml applications is the
3076following:</p>
3077<ol>
3078 <li>install the libxml-1.8.8 (and libxml-devel-1.8.8) packages</li>
3079 <li>find all occurences where the xmlDoc <strong>root</strong> field is
3080 used and change it to <strong>xmlRootNode</strong></li>
3081 <li>similary find all occurences where the xmlNode <strong>childs</strong>
3082 field is used and change it to <strong>xmlChildrenNode</strong></li>
3083 <li>add a <strong>LIBXML_TEST_VERSION</strong> macro somewhere in your
3084 <strong>main()</strong> or in the library init entry point</li>
3085 <li>Recompile, check compatibility, it should still work</li>
3086 <li>Change your configure script to look first for xml2-config and fallback
3087 using xml-config . Use the --cflags and --libs ouptut of the command as
3088 the Include and Linking parameters needed to use libxml.</li>
3089 <li>install libxml2-2.3.x and libxml2-devel-2.3.x (libxml-1.8.y and
3090 libxml-devel-1.8.y can be kept simultaneously)</li>
3091 <li>remove your config.cache, relaunch your configuration mechanism, and
3092 recompile, if steps 2 and 3 were done right it should compile as-is</li>
3093 <li>Test that your application is still running correctly, if not this may
3094 be due to extra empty nodes due to formating spaces being kept in libxml2
3095 contrary to libxml1, in that case insert xmlKeepBlanksDefault(1) in your
3096 code before calling the parser (next to
3097 <strong>LIBXML_TEST_VERSION</strong> is a fine place).</li>
3098</ol>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]3099
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]3100<p>Following those steps should work. It worked for some of my own code.</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]3101
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]3102<p>Let me put some emphasis on the fact that there is far more changes from
3103libxml 1.x to 2.x than the ones you may have to patch for. The overall code
3104has been considerably cleaned up and the conformance to the XML specification
3105has been drastically improved too. Don't take those changes as an excuse to
3106not upgrade, it may cost a lot on the long term ...</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]3107
Daniel Veillard52dcab32001-10-30 12:51:17 +0000[diff] [blame]3108<h2><a name="Thread">Thread safety</a></h2>
3109
3110<p>Starting with 2.4.7, libxml makes provisions to ensure that concurent
3111threads can safely work in parallel parsing different documents. There is
3112however a couple of things to do to ensure it:</p>
3113<ul>
3114 <li>configure the library accordingly using the --with-threads options</li>
3115 <li>call xmlInitParser() in the "main" thread before using any of the
3116 libxml API (except possibly selecting a different memory allocator)</li>
3117</ul>
3118
3119<p>Note that the thread safety cannot be ensured for multiple threads sharing
3120the same document, the locking must be done at the application level, libxml
3121exports a basic mutex and reentrant mutexes API in &lt;libxml/threads.h&gt;.
3122The parts of the library checked for thread safety are:</p>
3123<ul>
3124 <li>concurrent loading</li>
3125 <li>file access resolution</li>
3126 <li>catalog access</li>
3127 <li>catalog building</li>
3128 <li>entities lookup/accesses</li>
3129 <li>validation</li>
3130 <li>global variables per-thread override</li>
3131 <li>memory handling</li>
3132</ul>
3133
3134<p>XPath is supposed to be thread safe now, but this wasn't tested
3135seriously.</p>
3136
Daniel Veillard35008381999-10-25 13:15:52 +0000[diff] [blame]3137<h2><a name="DOM"></a><a name="Principles">DOM Principles</a></h2>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3138
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]3139<p><a href="http://www.w3.org/DOM/">DOM</a> stands for the <em>Document
3140Object Model</em>; this is an API for accessing XML or HTML structured
3141documents. Native support for DOM in Gnome is on the way (module gnome-dom),
3142and will be based on gnome-xml. This will be a far cleaner interface to
3143manipulate XML files within Gnome since it won't expose the internal
3144structure.</p>
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]3145
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]3146<p>The current DOM implementation on top of libxml is the <a
Daniel Veillarda47fb3d2001-03-25 17:23:49 +0000[diff] [blame]3147href="http://cvs.gnome.org/lxr/source/gdome2/">gdome2 Gnome module</a>, this
3148is a full DOM interface, thanks to Paolo Casarini, check the <a
3149href="http://www.cs.unibo.it/~casarini/gdome2/">Gdome2 homepage</a> for more
3150informations.</p>
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]3151
Daniel Veillard35008381999-10-25 13:15:52 +0000[diff] [blame]3152<h2><a name="Example"></a><a name="real">A real example</a></h2>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3153
3154<p>Here is a real size example, where the actual content of the application
3155data 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]3156a proposal to keep a database of jobs related to Gnome, with an XML based
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3157storage structure. Here is an <a href="gjobs.xml">XML encoded jobs
3158base</a>:</p>
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]3159<pre>&lt;?xml version="1.0"?&gt;
3160&lt;gjob:Helping xmlns:gjob="http://www.gnome.org/some-location"&gt;
3161 &lt;gjob:Jobs&gt;
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]3162
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]3163 &lt;gjob:Job&gt;
3164 &lt;gjob:Project ID="3"/&gt;
3165 &lt;gjob:Application&gt;GBackup&lt;/gjob:Application&gt;
3166 &lt;gjob:Category&gt;Development&lt;/gjob:Category&gt;
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]3167
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]3168 &lt;gjob:Update&gt;
3169 &lt;gjob:Status&gt;Open&lt;/gjob:Status&gt;
3170 &lt;gjob:Modified&gt;Mon, 07 Jun 1999 20:27:45 -0400 MET DST&lt;/gjob:Modified&gt;
3171 &lt;gjob:Salary&gt;USD 0.00&lt;/gjob:Salary&gt;
3172 &lt;/gjob:Update&gt;
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]3173
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]3174 &lt;gjob:Developers&gt;
3175 &lt;gjob:Developer&gt;
3176 &lt;/gjob:Developer&gt;
3177 &lt;/gjob:Developers&gt;
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]3178
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]3179 &lt;gjob:Contact&gt;
3180 &lt;gjob:Person&gt;Nathan Clemons&lt;/gjob:Person&gt;
3181 &lt;gjob:Email&gt;nathan@windsofstorm.net&lt;/gjob:Email&gt;
3182 &lt;gjob:Company&gt;
3183 &lt;/gjob:Company&gt;
3184 &lt;gjob:Organisation&gt;
3185 &lt;/gjob:Organisation&gt;
3186 &lt;gjob:Webpage&gt;
3187 &lt;/gjob:Webpage&gt;
3188 &lt;gjob:Snailmail&gt;
3189 &lt;/gjob:Snailmail&gt;
3190 &lt;gjob:Phone&gt;
3191 &lt;/gjob:Phone&gt;
3192 &lt;/gjob:Contact&gt;
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]3193
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]3194 &lt;gjob:Requirements&gt;
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]3195 The program should be released as free software, under the GPL.
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]3196 &lt;/gjob:Requirements&gt;
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]3197
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]3198 &lt;gjob:Skills&gt;
3199 &lt;/gjob:Skills&gt;
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]3200
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]3201 &lt;gjob:Details&gt;
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]3202 A GNOME based system that will allow a superuser to configure
3203 compressed and uncompressed files and/or file systems to be backed
3204 up with a supported media in the system. This should be able to
3205 perform via find commands generating a list of files that are passed
3206 to tar, dd, cpio, cp, gzip, etc., to be directed to the tape machine
3207 or via operations performed on the filesystem itself. Email
3208 notification and GUI status display very important.
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]3209 &lt;/gjob:Details&gt;
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]3210
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]3211 &lt;/gjob:Job&gt;
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]3212
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]3213 &lt;/gjob:Jobs&gt;
3214&lt;/gjob:Helping&gt;</pre>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3215
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]3216<p>While loading the XML file into an internal DOM tree is a matter of
3217calling only a couple of functions, browsing the tree to gather the ata and
3218generate the internal structures is harder, and more error prone.</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3219
3220<p>The suggested principle is to be tolerant with respect to the input
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]3221structure. For example, the ordering of the attributes is not significant,
3222the XML specification is clear about it. It's also usually a good idea not to
Daniel Veillardec70e912001-02-26 20:10:45 +0000[diff] [blame]3223depend on the order of the children of a given node, unless it really makes
3224things harder. Here is some code to parse the information for a person:</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3225<pre>/*
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]3226 * A person record
3227 */
3228typedef struct person {
3229 char *name;
3230 char *email;
3231 char *company;
3232 char *organisation;
3233 char *smail;
3234 char *webPage;
3235 char *phone;
3236} person, *personPtr;
3237
3238/*
3239 * And the code needed to parse it
3240 */
3241personPtr parsePerson(xmlDocPtr doc, xmlNsPtr ns, xmlNodePtr cur) {
3242 personPtr ret = NULL;
3243
3244DEBUG("parsePerson\n");
3245 /*
3246 * allocate the struct
3247 */
3248 ret = (personPtr) malloc(sizeof(person));
3249 if (ret == NULL) {
3250 fprintf(stderr,"out of memory\n");
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3251 return(NULL);
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]3252 }
3253 memset(ret, 0, sizeof(person));
3254
3255 /* We don't care what the top level element name is */
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]3256 cur = cur-&gt;xmlChildrenNode;
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]3257 while (cur != NULL) {
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]3258 if ((!strcmp(cur-&gt;name, "Person")) &amp;&amp; (cur-&gt;ns == ns))
3259 ret-&gt;name = xmlNodeListGetString(doc, cur-&gt;xmlChildrenNode, 1);
3260 if ((!strcmp(cur-&gt;name, "Email")) &amp;&amp; (cur-&gt;ns == ns))
3261 ret-&gt;email = xmlNodeListGetString(doc, cur-&gt;xmlChildrenNode, 1);
3262 cur = cur-&gt;next;
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]3263 }
3264
3265 return(ret);
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3266}</pre>
3267
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]3268<p>Here are a couple of things to notice:</p>
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]3269<ul>
Daniel Veillard91e9d582001-02-26 07:31:12 +0000[diff] [blame]3270 <li>Usually a recursive parsing style is the more convenient one: XML data
3271 is by nature subject to repetitive constructs and usually exibits highly
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3272 stuctured patterns.</li>
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]3273 <li>The two arguments of type <em>xmlDocPtr</em> and <em>xmlNsPtr</em>,
3274 i.e. the pointer to the global XML document and the namespace reserved to
3275 the application. Document wide information are needed for example to
3276 decode entities and it's a good coding practice to define a namespace for
3277 your application set of data and test that the element and attributes
3278 you're analyzing actually pertains to your application space. This is
3279 done by a simple equality test (cur-&gt;ns == ns).</li>
Daniel Veillardec70e912001-02-26 20:10:45 +0000[diff] [blame]3280 <li>To retrieve text and attributes value, you can use the function
3281 <em>xmlNodeListGetString</em> to gather all the text and entity reference
3282 nodes generated by the DOM output and produce an single text string.</li>
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]3283</ul>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3284
3285<p>Here is another piece of code used to parse another level of the
3286structure:</p>
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]3287<pre>#include &lt;libxml/tree.h&gt;
Daniel Veillard361d8452000-04-03 19:48:13 +0000[diff] [blame]3288/*
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]3289 * a Description for a Job
3290 */
3291typedef struct job {
3292 char *projectID;
3293 char *application;
3294 char *category;
3295 personPtr contact;
3296 int nbDevelopers;
3297 personPtr developers[100]; /* using dynamic alloc is left as an exercise */
3298} job, *jobPtr;
3299
3300/*
3301 * And the code needed to parse it
3302 */
3303jobPtr parseJob(xmlDocPtr doc, xmlNsPtr ns, xmlNodePtr cur) {
3304 jobPtr ret = NULL;
3305
3306DEBUG("parseJob\n");
3307 /*
3308 * allocate the struct
3309 */
3310 ret = (jobPtr) malloc(sizeof(job));
3311 if (ret == NULL) {
3312 fprintf(stderr,"out of memory\n");
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3313 return(NULL);
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]3314 }
3315 memset(ret, 0, sizeof(job));
3316
3317 /* We don't care what the top level element name is */
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]3318 cur = cur-&gt;xmlChildrenNode;
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]3319 while (cur != NULL) {
3320
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]3321 if ((!strcmp(cur-&gt;name, "Project")) &amp;&amp; (cur-&gt;ns == ns)) {
3322 ret-&gt;projectID = xmlGetProp(cur, "ID");
3323 if (ret-&gt;projectID == NULL) {
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3324 fprintf(stderr, "Project has no ID\n");
3325 }
3326 }
Daniel Veillard60979bd2000-07-10 12:17:33 +0000[diff] [blame]3327 if ((!strcmp(cur-&gt;name, "Application")) &amp;&amp; (cur-&gt;ns == ns))
3328 ret-&gt;application = xmlNodeListGetString(doc, cur-&gt;xmlChildrenNode, 1);
3329 if ((!strcmp(cur-&gt;name, "Category")) &amp;&amp; (cur-&gt;ns == ns))
3330 ret-&gt;category = xmlNodeListGetString(doc, cur-&gt;xmlChildrenNode, 1);
3331 if ((!strcmp(cur-&gt;name, "Contact")) &amp;&amp; (cur-&gt;ns == ns))
3332 ret-&gt;contact = parsePerson(doc, ns, cur);
3333 cur = cur-&gt;next;
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]3334 }
3335
3336 return(ret);
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3337}</pre>
Daniel Veillard14fff061999-06-22 21:49:07 +0000[diff] [blame]3338
Daniel Veillardec70e912001-02-26 20:10:45 +0000[diff] [blame]3339<p>Once you are used to it, writing this kind of code is quite simple, but
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]3340boring. Ultimately, it could be possble to write stubbers taking either C
3341data structure definitions, a set of XML examples or an XML DTD and produce
3342the code needed to import and export the content between C data and XML
3343storage. This is left as an exercise to the reader :-)</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3344
Daniel Veillard6f0adb52000-07-03 11:41:26 +0000[diff] [blame]3345<p>Feel free to use <a href="example/gjobread.c">the code for the full C
3346parsing example</a> as a template, it is also available with Makefile in the
3347Gnome CVS base under gnome-xml/example</p>
Daniel Veillardb05deb71999-08-10 19:04:08 +0000[diff] [blame]3348
Daniel Veillardc310d562000-06-23 18:32:15 +0000[diff] [blame]3349<h2><a name="Contributi">Contributions</a></h2>
3350<ul>
Daniel Veillardb8cfbd12001-10-25 10:53:28 +0000[diff] [blame]3351 <li>Bjorn Reese, William Brack and Thomas Broyer have provided a number of
3352 patches, Gary Pennington worked on the validation API, threading support
3353 and Solaris port.</li>
3354 <li>John Fleck helps maintaining the documentation and man pages.</li>
Daniel Veillardc6271d22001-10-27 07:50:58 +0000[diff] [blame]3355 <li><a href="mailto:ari@lusis.org">Ari Johnson</a>
Daniel Veillard51095312001-10-28 18:51:57 +0000[diff] [blame]3356 provides a C++ wrapper for libxml:<br>
Daniel Veillardc6271d22001-10-27 07:50:58 +0000[diff] [blame]3357 Website: <a
3358 href="http://lusis.org/~ari/xml++/">http://lusis.org/~ari/xml++/</a><br>
3359 Download: <a
Daniel Veillard51095312001-10-28 18:51:57 +0000[diff] [blame]3360 href="http://lusis.org/~ari/xml++/libxml++.tar.gz">http://lusis.org/~ari/xml++/libxml++.tar.gz</a></li>
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]3361 <li><a href="mailto:izlatkovic@daenet.de">Igor Zlatkovic</a>
3362 is now the maintainer of the Windows port, <a
Daniel Veillard95189532001-07-26 18:30:26 +0000[diff] [blame]3363 href="http://www.fh-frankfurt.de/~igor/projects/libxml/index.html">he
3364 provides binaries</a></li>
Daniel Veillardc9484202001-10-24 12:35:52 +0000[diff] [blame]3365 <li><a href="mailto:Gary.Pennington@sun.com">Gary Pennington</a>
Daniel Veillarddb9dfd92001-11-26 17:25:02 +0000[diff] [blame]3366 provides <a href="http://garypennington.net/libxml2/">Solaris
Daniel Veillard0a702dc2001-10-19 14:50:57 +0000[diff] [blame]3367 binaries</a></li>
Daniel Veillarde356c282001-03-10 12:32:04 +0000[diff] [blame]3368 <li><a
3369 href="http://mail.gnome.org/archives/xml/2001-March/msg00014.html">Matt
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]3370 Sergeant</a>
3371 developped <a href="http://axkit.org/download/">XML::LibXSLT</a>, a perl
3372 wrapper for libxml2/libxslt as part of the <a
3373 href="http://axkit.com/">AxKit XML application server</a></li>
3374 <li><a href="mailto:fnatter@gmx.net">Felix Natter</a>
3375 and <a href="mailto:geertk@ai.rug.nl">Geert Kloosterman</a> provide <a
Daniel Veillardca989762001-06-23 17:39:29 +0000[diff] [blame]3376 href="libxml-doc.el">an emacs module</a> to lookup libxml(2) functions
Daniel Veillard3f6f7f62000-06-30 17:58:25 +0000[diff] [blame]3377 documentation</li>
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]3378 <li><a href="mailto:sherwin@nlm.nih.gov">Ziying Sherwin</a>
3379 provided <a href="http://xmlsoft.org/messages/0488.html">man
3380 pages</a></li>
Daniel Veillard5168dbf2001-07-07 00:18:23 +0000[diff] [blame]3381 <li>there is a module for <a
3382 href="http://acs-misc.sourceforge.net/nsxml.html">libxml/libxslt support
3383 in OpenNSD/AOLServer</a></li>
Daniel Veillard3d6ae1c2001-08-15 13:12:39 +0000[diff] [blame]3384 <li><a href="mailto:dkuhlman@cutter.rexx.com">Dave Kuhlman</a>
3385 provides libxml/libxslt <a href="http://www.rexx.com/~dkuhlman">wrappers
3386 for Python</a></li>
Daniel Veillard1aadc442001-11-28 13:10:32 +0000[diff] [blame]3387 <li>Petr Kozelka provides <a
3388 href="http://sourceforge.net/projects/libxml2-pas">Pascal units to glue
3389 libxml2</a> with Kylix and Delphi and other Pascal compilers</li>
Daniel Veillardc310d562000-06-23 18:32:15 +0000[diff] [blame]3390</ul>
3391
Daniel Veillardc8eab3a1999-09-04 18:27:23 +0000[diff] [blame]3392<p></p>
Daniel Veillardccb09631998-10-27 06:21:04 +0000[diff] [blame]3393</body>
3394</html>