1<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" 2 "http://www.w3.org/TR/html4/loose.dtd"> 3<html> 4<head> 5 <title>The XML C parser and toolkit of Gnome</title> 6 <meta name="GENERATOR" content="amaya 8.5, see http://www.w3.org/Amaya/"> 7 <meta http-equiv="Content-Type" content="text/html"> 8</head> 9<body bgcolor="#ffffff"> 10<h1 align="center">The XML C parser and toolkit of Gnome</h1> 11 12<h1>Note: this is the flat content of the <a href="index.html">web 13site</a></h1> 14 15<h1 style="text-align: center">libxml, a.k.a. gnome-xml</h1> 16 17<p></p> 18 19<p 20style="text-align: right; font-style: italic; font-size: 10pt">"Programming 21with libxml2 is like the thrilling embrace of an exotic stranger." <a 22href="http://diveintomark.org/archives/2004/02/18/libxml2">Mark 23Pilgrim</a></p> 24 25<p>Libxml2 is the XML C parser and toolkit developed for the Gnome project 26(but usable outside of the Gnome platform), it is free software available 27under the <a href="http://www.opensource.org/licenses/mit-license.html">MIT 28License</a>. XML itself is a metalanguage to design markup languages, i.e. 29text language where semantic and structure are added to the content using 30extra "markup" information enclosed between angle brackets. HTML is the most 31well-known markup language. Though the library is written in C <a 32href="python.html">a variety of language bindings</a> make it available in 33other environments.</p> 34 35<p>Libxml2 is known to be very portable, the library should build and work 36without serious troubles on a variety of systems (Linux, Unix, Windows, 37CygWin, MacOS, MacOS X, RISC Os, OS/2, VMS, QNX, MVS, ...)</p> 38 39<p>Libxml2 implements a number of existing standards related to markup 40languages:</p> 41<ul> 42 <li>the XML standard: <a 43 href="http://www.w3.org/TR/REC-xml">http://www.w3.org/TR/REC-xml</a></li> 44 <li>Namespaces in XML: <a 45 href="http://www.w3.org/TR/REC-xml-names/">http://www.w3.org/TR/REC-xml-names/</a></li> 46 <li>XML Base: <a 47 href="http://www.w3.org/TR/xmlbase/">http://www.w3.org/TR/xmlbase/</a></li> 48 <li><a href="http://www.cis.ohio-state.edu/rfc/rfc2396.txt">RFC 2396</a> : 49 Uniform Resource Identifiers <a 50 href="http://www.ietf.org/rfc/rfc2396.txt">http://www.ietf.org/rfc/rfc2396.txt</a></li> 51 <li>XML Path Language (XPath) 1.0: <a 52 href="http://www.w3.org/TR/xpath">http://www.w3.org/TR/xpath</a></li> 53 <li>HTML4 parser: <a 54 href="http://www.w3.org/TR/html401/">http://www.w3.org/TR/html401/</a></li> 55 <li>XML Pointer Language (XPointer) Version 1.0: <a 56 href="http://www.w3.org/TR/xptr">http://www.w3.org/TR/xptr</a></li> 57 <li>XML Inclusions (XInclude) Version 1.0: <a 58 href="http://www.w3.org/TR/xinclude/">http://www.w3.org/TR/xinclude/</a></li> 59 <li>ISO-8859-x encodings, as well as <a 60 href="http://www.cis.ohio-state.edu/rfc/rfc2044.txt">rfc2044</a> [UTF-8] 61 and <a href="http://www.cis.ohio-state.edu/rfc/rfc2781.txt">rfc2781</a> 62 [UTF-16] Unicode encodings, and more if using iconv support</li> 63 <li>part of SGML Open Technical Resolution TR9401:1997</li> 64 <li>XML Catalogs Working Draft 06 August 2001: <a 65 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> 66 <li>Canonical XML Version 1.0: <a 67 href="http://www.w3.org/TR/xml-c14n">http://www.w3.org/TR/xml-c14n</a> 68 and the Exclusive XML Canonicalization CR draft <a 69 href="http://www.w3.org/TR/xml-exc-c14n">http://www.w3.org/TR/xml-exc-c14n</a></li> 70 <li>Relax NG, ISO/IEC 19757-2:2003, <a 71 href="http://www.oasis-open.org/committees/relax-ng/spec-20011203.html">http://www.oasis-open.org/committees/relax-ng/spec-20011203.html</a></li> 72 <li>W3C XML Schemas Part 2: Datatypes <a 73 href="http://www.w3.org/TR/2001/REC-xmlschema-2-20010502/">REC 02 May 74 2001</a></li> 75 <li>W3C <a href="http://www.w3.org/TR/xml-id/">xml:id</a> Working Draft 7 76 April 2004</li> 77</ul> 78 79<p>In most cases libxml2 tries to implement the specifications in a 80relatively strictly compliant way. As of release 2.4.16, libxml2 passed all 811800+ tests from the <a 82href="http://www.oasis-open.org/committees/xml-conformance/">OASIS XML Tests 83Suite</a>.</p> 84 85<p>To some extent libxml2 provides support for the following additional 86specifications but doesn't claim to implement them completely:</p> 87<ul> 88 <li>Document Object Model (DOM) <a 89 href="http://www.w3.org/TR/DOM-Level-2-Core/">http://www.w3.org/TR/DOM-Level-2-Core/</a> 90 the document model, but it doesn't implement the API itself, gdome2 does 91 this on top of libxml2</li> 92 <li><a href="http://www.cis.ohio-state.edu/rfc/rfc959.txt">RFC 959</a> : 93 libxml2 implements a basic FTP client code</li> 94 <li><a href="http://www.cis.ohio-state.edu/rfc/rfc1945.txt">RFC 1945</a> : 95 HTTP/1.0, again a basic HTTP client code</li> 96 <li>SAX: a SAX2 like interface and a minimal SAX1 implementation compatible 97 with early expat versions</li> 98</ul> 99 100<p>A partial implementation of <a 101href="http://www.w3.org/TR/2001/REC-xmlschema-1-20010502/">XML Schemas Part 1021: Structure</a> is being worked on but it would be far too early to make any 103conformance statement about it at the moment.</p> 104 105<p>Separate documents:</p> 106<ul> 107 <li><a href="http://xmlsoft.org/XSLT/">the libxslt page</a> providing an 108 implementation of XSLT 1.0 and common extensions like EXSLT for 109 libxml2</li> 110 <li><a href="http://gdome2.cs.unibo.it/">the gdome2 page</a> 111 : a standard DOM2 implementation for libxml2</li> 112 <li><a href="http://www.aleksey.com/xmlsec/">the XMLSec page</a>: an 113 implementation of <a href="http://www.w3.org/TR/xmldsig-core/">W3C XML 114 Digital Signature</a> for libxml2</li> 115 <li>also check the related links section below for more related and active 116 projects.</li> 117</ul> 118<!-- ----------------<p>Results of the <a 119href="http://xmlbench.sourceforge.net/results/benchmark/index.html">xmlbench 120benchmark</a> on sourceforge February 2004 (smaller is better):</p> 121 122<p align="center"><img src="benchmark.png" 123alt="benchmark results for Expat Xerces libxml2 Oracle and Sun toolkits"></p> 124------------ --> 125 126<p>Logo designed by <a href="mailto:liyanage@access.ch">Marc Liyanage</a>.</p> 127 128<h2><a name="Introducti">Introduction</a></h2> 129 130<p>This document describes libxml, the <a 131href="http://www.w3.org/XML/">XML</a> C parser and toolkit developed for the 132<a href="http://www.gnome.org/">Gnome</a> project. <a 133href="http://www.w3.org/XML/">XML is a standard</a> for building tag-based 134structured documents/data.</p> 135 136<p>Here are some key points about libxml:</p> 137<ul> 138 <li>Libxml2 exports Push (progressive) and Pull (blocking) type parser 139 interfaces for both XML and HTML.</li> 140 <li>Libxml2 can do DTD validation at parse time, using a parsed document 141 instance, or with an arbitrary DTD.</li> 142 <li>Libxml2 includes complete <a 143 href="http://www.w3.org/TR/xpath">XPath</a>, <a 144 href="http://www.w3.org/TR/xptr">XPointer</a> and <a 145 href="http://www.w3.org/TR/xinclude">XInclude</a> implementations.</li> 146 <li>It is written in plain C, making as few assumptions as possible, and 147 sticking closely to ANSI C/POSIX for easy embedding. Works on 148 Linux/Unix/Windows, ported to a number of other platforms.</li> 149 <li>Basic support for HTTP and FTP client allowing applications to fetch 150 remote resources.</li> 151 <li>The design is modular, most of the extensions can be compiled out.</li> 152 <li>The internal document representation is as close as possible to the <a 153 href="http://www.w3.org/DOM/">DOM</a> interfaces.</li> 154 <li>Libxml2 also has a <a 155 href="http://www.megginson.com/SAX/index.html">SAX like interface</a>; 156 the interface is designed to be compatible with <a 157 href="http://www.jclark.com/xml/expat.html">Expat</a>.</li> 158 <li>This library is released under the <a 159 href="http://www.opensource.org/licenses/mit-license.html">MIT 160 License</a>. See the Copyright file in the distribution for the precise 161 wording.</li> 162</ul> 163 164<p>Warning: unless you are forced to because your application links with a 165Gnome-1.X library requiring it, <strong><span 166style="background-color: #FF0000">Do Not Use libxml1</span></strong>, use 167libxml2</p> 168 169<h2><a name="FAQ">FAQ</a></h2> 170 171<p>Table of Contents:</p> 172<ul> 173 <li><a href="FAQ.html#License">License(s)</a></li> 174 <li><a href="FAQ.html#Installati">Installation</a></li> 175 <li><a href="FAQ.html#Compilatio">Compilation</a></li> 176 <li><a href="FAQ.html#Developer">Developer corner</a></li> 177</ul> 178 179<h3><a name="License">License</a>(s)</h3> 180<ol> 181 <li><em>Licensing Terms for libxml</em> 182 <p>libxml2 is released under the <a 183 href="http://www.opensource.org/licenses/mit-license.html">MIT 184 License</a>; see the file Copyright in the distribution for the precise 185 wording</p> 186 </li> 187 <li><em>Can I embed libxml2 in a proprietary application ?</em> 188 <p>Yes. The MIT License allows you to keep proprietary the changes you 189 made to libxml, but it would be graceful to send-back bug fixes and 190 improvements as patches for possible incorporation in the main 191 development tree.</p> 192 </li> 193</ol> 194 195<h3><a name="Installati">Installation</a></h3> 196<ol> 197 <li><strong><span style="background-color: #FF0000">Do Not Use 198 libxml1</span></strong>, use libxml2</li> 199 <p></p> 200 <li><em>Where can I get libxml</em> ? 201 <p>The original distribution comes from <a 202 href="ftp://xmlsoft.org/libxml2/">xmlsoft.org</a> or <a 203 href="ftp://ftp.gnome.org/pub/GNOME/sources/libxml2/2.6/">gnome.org</a></p> 204 <p>Most Linux and BSD distributions include libxml, this is probably the 205 safer way for end-users to use libxml.</p> 206 <p>David Doolin provides precompiled Windows versions at <a 207 href="http://www.ce.berkeley.edu/~doolin/code/libxmlwin32/ ">http://www.ce.berkeley.edu/~doolin/code/libxmlwin32/</a></p> 208 </li> 209 <p></p> 210 <li><em>I see libxml and libxml2 releases, which one should I install ?</em> 211 <ul> 212 <li>If you are not constrained by backward compatibility issues with 213 existing applications, install libxml2 only</li> 214 <li>If you are not doing development, you can safely install both. 215 Usually the packages <a 216 href="http://rpmfind.net/linux/RPM/libxml.html">libxml</a> and <a 217 href="http://rpmfind.net/linux/RPM/libxml2.html">libxml2</a> are 218 compatible (this is not the case for development packages).</li> 219 <li>If you are a developer and your system provides separate packaging 220 for shared libraries and the development components, it is possible 221 to install libxml and libxml2, and also <a 222 href="http://rpmfind.net/linux/RPM/libxml-devel.html">libxml-devel</a> 223 and <a 224 href="http://rpmfind.net/linux/RPM/libxml2-devel.html">libxml2-devel</a> 225 too for libxml2 >= 2.3.0</li> 226 <li>If you are developing a new application, please develop against 227 libxml2(-devel)</li> 228 </ul> 229 </li> 230 <li><em>I can't install the libxml package, it conflicts with libxml0</em> 231 <p>You probably have an old libxml0 package used to provide the shared 232 library for libxml.so.0, you can probably safely remove it. The libxml 233 packages provided on <a 234 href="ftp://xmlsoft.org/libxml2/">xmlsoft.org</a> provide 235 libxml.so.0</p> 236 </li> 237 <li><em>I can't install the libxml(2) RPM package due to failed 238 dependencies</em> 239 <p>The most generic solution is to re-fetch the latest src.rpm , and 240 rebuild it locally with</p> 241 <p><code>rpm --rebuild libxml(2)-xxx.src.rpm</code>.</p> 242 <p>If everything goes well it will generate two binary rpm packages (one 243 providing the shared libs and xmllint, and the other one, the -devel 244 package, providing includes, static libraries and scripts needed to build 245 applications with libxml(2)) that you can install locally.</p> 246 </li> 247</ol> 248 249<h3><a name="Compilatio">Compilation</a></h3> 250<ol> 251 <li><em>What is the process to compile libxml2 ?</em> 252 <p>As most UNIX libraries libxml2 follows the "standard":</p> 253 <p><code>gunzip -c xxx.tar.gz | tar xvf -</code></p> 254 <p><code>cd libxml-xxxx</code></p> 255 <p><code>./configure --help</code></p> 256 <p>to see the options, then the compilation/installation proper</p> 257 <p><code>./configure [possible options]</code></p> 258 <p><code>make</code></p> 259 <p><code>make install</code></p> 260 <p>At that point you may have to rerun ldconfig or a similar utility to 261 update your list of installed shared libs.</p> 262 </li> 263 <li><em>What other libraries are needed to compile/install libxml2 ?</em> 264 <p>Libxml2 does not require any other library, the normal C ANSI API 265 should be sufficient (please report any violation to this rule you may 266 find).</p> 267 <p>However if found at configuration time libxml2 will detect and use the 268 following libs:</p> 269 <ul> 270 <li><a href="http://www.info-zip.org/pub/infozip/zlib/">libz</a> : a 271 highly portable and available widely compression library.</li> 272 <li>iconv: a powerful character encoding conversion library. It is 273 included by default in recent glibc libraries, so it doesn't need to 274 be installed specifically on Linux. It now seems a <a 275 href="http://www.opennc.org/onlinepubs/7908799/xsh/iconv.html">part 276 of the official UNIX</a> specification. Here is one <a 277 href="http://www.gnu.org/software/libiconv/">implementation of the 278 library</a> which source can be found <a 279 href="ftp://ftp.ilog.fr/pub/Users/haible/gnu/">here</a>.</li> 280 </ul> 281 </li> 282 <p></p> 283 <li><em>Make check fails on some platforms</em> 284 <p>Sometimes the regression tests' results don't completely match the 285 value produced by the parser, and the makefile uses diff to print the 286 delta. On some platforms the diff return breaks the compilation process; 287 if the diff is small this is probably not a serious problem.</p> 288 <p>Sometimes (especially on Solaris) make checks fail due to limitations 289 in make. Try using GNU-make instead.</p> 290 </li> 291 <li><em>I use the SVN version and there is no configure script</em> 292 <p>The configure script (and other Makefiles) are generated. Use the 293 autogen.sh script to regenerate the configure script and Makefiles, 294 like:</p> 295 <p><code>./autogen.sh --prefix=/usr --disable-shared</code></p> 296 </li> 297 <li><em>I have troubles when running make tests with gcc-3.0</em> 298 <p>It seems the initial release of gcc-3.0 has a problem with the 299 optimizer which miscompiles the URI module. Please use another 300 compiler.</p> 301 </li> 302</ol> 303 304<h3><a name="Developer">Developer</a> corner</h3> 305<ol> 306 <li><em>Troubles compiling or linking programs using libxml2</em> 307 <p>Usually the problem comes from the fact that the compiler doesn't get 308 the right compilation or linking flags. There is a small shell script 309 <code>xml2-config</code> which is installed as part of libxml2 usual 310 install process which provides those flags. Use</p> 311 <p><code>xml2-config --cflags</code></p> 312 <p>to get the compilation flags and</p> 313 <p><code>xml2-config --libs</code></p> 314 <p>to get the linker flags. Usually this is done directly from the 315 Makefile as:</p> 316 <p><code>CFLAGS=`xml2-config --cflags`</code></p> 317 <p><code>LIBS=`xml2-config --libs`</code></p> 318 </li> 319 <li><em>I want to install my own copy of libxml2 in my home directory and 320 link my programs against it, but it doesn't work</em> 321 <p>There are many different ways to accomplish this. Here is one way to 322 do this under Linux. Suppose your home directory is <code>/home/user. 323 </code>Then:</p> 324 <ul> 325 <li>Create a subdirectory, let's call it <code>myxml</code></li> 326 <li>unpack the libxml2 distribution into that subdirectory</li> 327 <li>chdir into the unpacked distribution 328 (<code>/home/user/myxml/libxml2 </code>)</li> 329 <li>configure the library using the "<code>--prefix</code>" switch, 330 specifying an installation subdirectory in 331 <code>/home/user/myxml</code>, e.g. 332 <p><code>./configure --prefix /home/user/myxml/xmlinst</code> {other 333 configuration options}</p> 334 </li> 335 <li>now run <code>make</code> followed by <code>make install</code></li> 336 <li>At this point, the installation subdirectory contains the complete 337 "private" include files, library files and binary program files (e.g. 338 xmllint), located in 339 <p><code>/home/user/myxml/xmlinst/lib, 340 /home/user/myxml/xmlinst/include </code> and <code> 341 /home/user/myxml/xmlinst/bin</code></p> 342 respectively.</li> 343 <li>In order to use this "private" library, you should first add it to 344 the beginning of your default PATH (so that your own private program 345 files such as xmllint will be used instead of the normal system 346 ones). To do this, the Bash command would be 347 <p><code>export PATH=/home/user/myxml/xmlinst/bin:$PATH</code></p> 348 </li> 349 <li>Now suppose you have a program <code>test1.c</code> that you would 350 like to compile with your "private" library. Simply compile it using 351 the command 352 <p><code>gcc `xml2-config --cflags --libs` -o test test.c</code></p> 353 Note that, because your PATH has been set with <code> 354 /home/user/myxml/xmlinst/bin</code> at the beginning, the xml2-config 355 program which you just installed will be used instead of the system 356 default one, and this will <em>automatically</em> get the correct 357 libraries linked with your program.</li> 358 </ul> 359 </li> 360 361 <p></p> 362 <li><em>xmlDocDump() generates output on one line.</em> 363 <p>Libxml2 will not <strong>invent</strong> spaces in the content of a 364 document since <strong>all spaces in the content of a document are 365 significant</strong>. If you build a tree from the API and want 366 indentation:</p> 367 <ol> 368 <li>the correct way is to generate those yourself too.</li> 369 <li>the dangerous way is to ask libxml2 to add those blanks to your 370 content <strong>modifying the content of your document in the 371 process</strong>. The result may not be what you expect. There is 372 <strong>NO</strong> way to guarantee that such a modification won't 373 affect other parts of the content of your document. See <a 374 href="http://xmlsoft.org/html/libxml-parser.html#xmlKeepBlanksDefault">xmlKeepBlanksDefault 375 ()</a> and <a 376 href="http://xmlsoft.org/html/libxml-tree.html#xmlSaveFormatFile">xmlSaveFormatFile 377 ()</a></li> 378 </ol> 379 </li> 380 <p></p> 381 <li><em>Extra nodes in the document:</em> 382 <p><em>For an XML file as below:</em></p> 383 <pre><?xml version="1.0"?> 384<PLAN xmlns="http://www.argus.ca/autotest/1.0/"> 385<NODE CommFlag="0"/> 386<NODE CommFlag="1"/> 387</PLAN></pre> 388 <p><em>after parsing it with the function 389 pxmlDoc=xmlParseFile(...);</em></p> 390 <p><em>I want to the get the content of the first node (node with the 391 CommFlag="0")</em></p> 392 <p><em>so I did it as following;</em></p> 393 <pre>xmlNodePtr pnode; 394pnode=pxmlDoc->children->children;</pre> 395 <p><em>but it does not work. If I change it to</em></p> 396 <pre>pnode=pxmlDoc->children->children->next;</pre> 397 <p><em>then it works. Can someone explain it to me.</em></p> 398 <p></p> 399 <p>In XML all characters in the content of the document are significant 400 <strong>including blanks and formatting line breaks</strong>.</p> 401 <p>The extra nodes you are wondering about are just that, text nodes with 402 the formatting spaces which are part of the document but that people tend 403 to forget. There is a function <a 404 href="http://xmlsoft.org/html/libxml-parser.html">xmlKeepBlanksDefault 405 ()</a> to remove those at parse time, but that's an heuristic, and its 406 use should be limited to cases where you are certain there is no 407 mixed-content in the document.</p> 408 </li> 409 <li><em>I get compilation errors of existing code like when accessing 410 <strong>root</strong> or <strong>child fields</strong> of nodes.</em> 411 <p>You are compiling code developed for libxml version 1 and using a 412 libxml2 development environment. Either switch back to libxml v1 devel or 413 even better fix the code to compile with libxml2 (or both) by <a 414 href="upgrade.html">following the instructions</a>.</p> 415 </li> 416 <li><em>I get compilation errors about non existing 417 <strong>xmlRootNode</strong> or <strong>xmlChildrenNode</strong> 418 fields.</em> 419 <p>The source code you are using has been <a 420 href="upgrade.html">upgraded</a> to be able to compile with both libxml 421 and libxml2, but you need to install a more recent version: 422 libxml(-devel) >= 1.8.8 or libxml2(-devel) >= 2.1.0</p> 423 </li> 424 <li><em>Random crashes in threaded applications</em> 425 <p>Read and follow all advices on the <a href="threads.html">thread 426 safety</a> page, and make 100% sure you never call xmlCleanupParser() 427 while the library or an XML document might still be in use by another 428 thread.</p> 429 </li> 430 <li><em>The example provided in the web page does not compile.</em> 431 <p>It's hard to maintain the documentation in sync with the code 432 <grin/> ...</p> 433 <p>Check the previous points 1/ and 2/ raised before, and please send 434 patches.</p> 435 </li> 436 <li><em>Where can I get more examples and information than provided on the 437 web page?</em> 438 <p>Ideally a libxml2 book would be nice. I have no such plan ... But you 439 can:</p> 440 <ul> 441 <li>check more deeply the <a href="html/libxml-lib.html">existing 442 generated doc</a></li> 443 <li>have a look at <a href="examples/index.html">the set of 444 examples</a>.</li> 445 <li>look for examples of use for libxml2 function using the Gnome code 446 or by asking on Google.</li> 447 <li><a 448 href="http://svn.gnome.org/viewcvs/libxml2/trunk/">Browse 449 the libxml2 source</a> , I try to write code as clean and documented 450 as possible, so looking at it may be helpful. In particular the code 451 of <a href="http://svn.gnome.org/viewcvs/libxml2/trunk/xmllint.c?view=markup">xmllint.c</a> and of the various testXXX.c test programs should 452 provide good examples of how to do things with the library.</li> 453 </ul> 454 </li> 455 <p></p> 456 <li><em>What about C++ ?</em> 457 <p>libxml2 is written in pure C in order to allow easy reuse on a number 458 of platforms, including embedded systems. I don't intend to convert to 459 C++.</p> 460 <p>There is however a C++ wrapper which may fulfill your needs:</p> 461 <ul> 462 <li>by Ari Johnson <ari@btigate.com>: 463 <p>Website: <a 464 href="http://libxmlplusplus.sourceforge.net/">http://libxmlplusplus.sourceforge.net/</a></p> 465 <p>Download: <a 466 href="http://sourceforge.net/project/showfiles.php?group_id=12999">http://sourceforge.net/project/showfiles.php?group_id=12999</a></p> 467 </li> 468 </ul> 469 </li> 470 <li><em>How to validate a document a posteriori ?</em> 471 <p>It is possible to validate documents which had not been validated at 472 initial parsing time or documents which have been built from scratch 473 using the API. Use the <a 474 href="http://xmlsoft.org/html/libxml-valid.html#xmlValidateDtd">xmlValidateDtd()</a> 475 function. It is also possible to simply add a DTD to an existing 476 document:</p> 477 <pre>xmlDocPtr doc; /* your existing document */ 478xmlDtdPtr dtd = xmlParseDTD(NULL, filename_of_dtd); /* parse the DTD */ 479 480 dtd->name = xmlStrDup((xmlChar*)"root_name"); /* use the given root */ 481 482 doc->intSubset = dtd; 483 if (doc->children == NULL) xmlAddChild((xmlNodePtr)doc, (xmlNodePtr)dtd); 484 else xmlAddPrevSibling(doc->children, (xmlNodePtr)dtd); 485 </pre> 486 </li> 487 <li><em>So what is this funky "xmlChar" used all the time?</em> 488 <p>It is a null terminated sequence of utf-8 characters. And only utf-8! 489 You need to convert strings encoded in different ways to utf-8 before 490 passing them to the API. This can be accomplished with the iconv library 491 for instance.</p> 492 </li> 493 <li>etc ...</li> 494</ol> 495 496<p></p> 497 498<h2><a name="Documentat">Developer Menu</a></h2> 499 500<p>There are several on-line resources related to using libxml:</p> 501<ol> 502 <li>Use the <a href="search.php">search engine</a> to look up 503 information.</li> 504 <li>Check the <a href="FAQ.html">FAQ.</a></li> 505 <li>Check the <a href="http://xmlsoft.org/html/libxml-lib.html">extensive 506 documentation</a> automatically extracted from code comments.</li> 507 <li>Look at the documentation about <a href="encoding.html">libxml 508 internationalization support</a>.</li> 509 <li>This page provides a global overview and <a href="example.html">some 510 examples</a> on how to use libxml.</li> 511 <li><a href="examples/index.html">Code examples</a></li> 512 <li>John Fleck's libxml2 tutorial: <a href="tutorial/index.html">html</a> 513 or <a href="tutorial/xmltutorial.pdf">pdf</a>.</li> 514 <li>If you need to parse large files, check the <a 515 href="xmlreader.html">xmlReader</a> API tutorial</li> 516 <li><a href="mailto:james@daa.com.au">James Henstridge</a> wrote <a 517 href="http://www.daa.com.au/~james/gnome/xml-sax/xml-sax.html">some nice 518 documentation</a> explaining how to use the libxml SAX interface.</li> 519 <li>George Lebl wrote <a 520 href="http://www-106.ibm.com/developerworks/library/l-gnome3/">an article 521 for IBM developerWorks</a> about using libxml.</li> 522 <li>Check <a href="http://svn.gnome.org/viewcvs/libxml2/trunk/TODO?view=markup">the TODO 523 file</a>.</li> 524 <li>Read the <a href="upgrade.html">1.x to 2.x upgrade path</a> 525 description. If you are starting a new project using libxml you should 526 really use the 2.x version.</li> 527 <li>And don't forget to look at the <a 528 href="http://mail.gnome.org/archives/xml/">mailing-list archive</a>.</li> 529</ol> 530 531<h2><a name="Reporting">Reporting bugs and getting help</a></h2> 532 533<p>Well, bugs or missing features are always possible, and I will make a 534point of fixing them in a timely fashion. The best way to report a bug is to 535use the <a href="http://bugzilla.gnome.org/buglist.cgi?product=libxml2">Gnome 536bug tracking database</a> (make sure to use the "libxml2" module name). I 537look at reports there regularly and it's good to have a reminder when a bug 538is still open. Be sure to specify that the bug is for the package libxml2.</p> 539 540<p>For small problems you can try to get help on IRC, the #xml channel on 541irc.gnome.org (port 6667) usually have a few person subscribed which may help 542(but there is no guarantee and if a real issue is raised it should go on the 543mailing-list for archival).</p> 544 545<p>There is also a mailing-list <a 546href="mailto:xml@gnome.org">xml@gnome.org</a> for libxml, with an <a 547href="http://mail.gnome.org/archives/xml/">on-line archive</a> (<a 548href="http://xmlsoft.org/messages">old</a>). To subscribe to this list, 549please visit the <a 550href="http://mail.gnome.org/mailman/listinfo/xml">associated Web</a> page and 551follow the instructions. <strong>Do not send code, I won't debug it</strong> 552(but patches are really appreciated!).</p> 553 554<p>Please note that with the current amount of virus and SPAM, sending mail 555to the list without being subscribed won't work. There is *far too many 556bounces* (in the order of a thousand a day !) I cannot approve them manually 557anymore. If your mail to the list bounced waiting for administrator approval, 558it is LOST ! Repost it and fix the problem triggering the error. Also please 559note that <span style="color: #FF0000; background-color: #FFFFFF">emails with 560a legal warning asking to not copy or redistribute freely the information 561they contain</span> are <strong>NOT</strong> acceptable for the mailing-list, 562such mail will as much as possible be discarded automatically, and are less 563likely to be answered if they made it to the list, <strong>DO NOT</strong> 564post to the list from an email address where such legal requirements are 565automatically added, get private paying support if you can't share 566information.</p> 567 568<p>Check the following <strong><span style="color: #FF0000">before 569posting</span></strong>:</p> 570<ul> 571 <li>Read the <a href="FAQ.html">FAQ</a> and <a href="search.php">use the 572 search engine</a> to get information related to your problem.</li> 573 <li>Make sure you are <a href="ftp://xmlsoft.org/libxml2/">using a recent 574 version</a>, and that the problem still shows up in a recent version.</li> 575 <li>Check the <a href="http://mail.gnome.org/archives/xml/">list 576 archives</a> to see if the problem was reported already. In this case 577 there is probably a fix available, similarly check the <a 578 href="http://bugzilla.gnome.org/buglist.cgi?product=libxml2">registered 579 open bugs</a>.</li> 580 <li>Make sure you can reproduce the bug with xmllint or one of the test 581 programs found in source in the distribution.</li> 582 <li>Please send the command showing the error as well as the input (as an 583 attachment)</li> 584</ul> 585 586<p>Then send the bug with associated information to reproduce it to the <a 587href="mailto:xml@gnome.org">xml@gnome.org</a> list; if it's really libxml 588related I will approve it. Please do not send mail to me directly, it makes 589things really hard to track and in some cases I am not the best person to 590answer a given question, ask on the list.</p> 591 592<p>To <span style="color: #E50000">be really clear about support</span>:</p> 593<ul> 594 <li>Support or help <span style="color: #E50000">requests MUST be sent to 595 the list or on bugzilla</span> in case of problems, so that the Question 596 and Answers can be shared publicly. Failing to do so carries the implicit 597 message "I want free support but I don't want to share the benefits with 598 others" and is not welcome. I will automatically Carbon-Copy the 599 xml@gnome.org mailing list for any technical reply made about libxml2 or 600 libxslt.</li> 601 <li>There is <span style="color: #E50000">no guarantee of support</span>. If 602 your question remains unanswered after a week, repost it, making sure you 603 gave all the detail needed and the information requested.</li> 604 <li>Failing to provide information as requested or double checking first 605 for prior feedback also carries the implicit message "the time of the 606 library maintainers is less valuable than my time" and might not be 607 welcome.</li> 608</ul> 609 610<p>Of course, bugs reported with a suggested patch for fixing them will 611probably be processed faster than those without.</p> 612 613<p>If you're looking for help, a quick look at <a 614href="http://mail.gnome.org/archives/xml/">the list archive</a> may actually 615provide the answer. I usually send source samples when answering libxml2 616usage questions. The <a 617href="http://xmlsoft.org/html/book1.html">auto-generated documentation</a> is 618not as polished as I would like (i need to learn more about DocBook), but 619it's a good starting point.</p> 620 621<h2><a name="help">How to help</a></h2> 622 623<p>You can help the project in various ways, the best thing to do first is to 624subscribe to the mailing-list as explained before, check the <a 625href="http://mail.gnome.org/archives/xml/">archives </a>and the <a 626href="http://bugzilla.gnome.org/buglist.cgi?product=libxml2">Gnome bug 627database</a>:</p> 628<ol> 629 <li>Provide patches when you find problems.</li> 630 <li>Provide the diffs when you port libxml2 to a new platform. They may not 631 be integrated in all cases but help pinpointing portability problems 632 and</li> 633 <li>Provide documentation fixes (either as patches to the code comments or 634 as HTML diffs).</li> 635 <li>Provide new documentations pieces (translations, examples, etc 636 ...).</li> 637 <li>Check the TODO file and try to close one of the items.</li> 638 <li>Take one of the points raised in the archive or the bug database and 639 provide a fix. <a href="mailto:daniel@veillard.com">Get in touch with me 640 </a>before to avoid synchronization problems and check that the suggested 641 fix will fit in nicely :-)</li> 642</ol> 643 644<h2><a name="Downloads">Downloads</a></h2> 645 646<p>The latest versions of libxml2 can be found on the <a 647href="ftp://xmlsoft.org/libxml2/">xmlsoft.org</a> server ( <a 648href="ftp://xmlsoft.org/libxml2/">FTP</a> and rsync are available), there are also 649mirrors (<a href="ftp://ftp.planetmirror.com/pub/xmlsoft/">Australia</a>( <a 650href="http://xmlsoft.planetmirror.com/">Web</a>), <a 651href="ftp://fr.rpmfind.net/pub/libxml/">France</a>) or on the <a 652href="ftp://ftp.gnome.org/pub/GNOME/MIRRORS.html">Gnome FTP server</a> as <a 653href="ftp://ftp.gnome.org/pub/GNOME/sources/libxml2/2.6/">source archive</a> 654, Antonin Sprinzl also provide <a href="ftp://gd.tuwien.ac.at/pub/libxml/">a 655mirror in Austria</a>. (NOTE that you need both the <a 656href="http://rpmfind.net/linux/RPM/libxml2.html">libxml(2)</a> and <a 657href="http://rpmfind.net/linux/RPM/libxml2-devel.html">libxml(2)-devel</a> 658packages installed to compile applications using libxml.)</p> 659 660<p>You can find all the history of libxml(2) and libxslt releases in the <a 661href="http://xmlsoft.org/sources/old/">old</a> directory. The precompiled 662Windows binaries made by Igor Zlatovic are available in the <a 663href="http://xmlsoft.org/sources/win32/">win32</a> directory.</p> 664 665<p>Binary ports:</p> 666<ul> 667 <li>Red Hat RPMs for i386 are available directly on <a 668 href="ftp://xmlsoft.org/libxml2/">xmlsoft.org</a>, the source RPM will compile on 669 any architecture supported by Red Hat.</li> 670 <li><a href="mailto:igor@zlatkovic.com">Igor Zlatkovic</a> is now the 671 maintainer of the Windows port, <a 672 href="http://www.zlatkovic.com/projects/libxml/index.html">he provides 673 binaries</a>.</li> 674 <li>Blastwave provides <a 675 href="http://www.blastwave.org/packages.php/libxml2">Solaris 676 binaries</a>.</li> 677 <li><a href="mailto:Steve.Ball@explain.com.au">Steve Ball</a> provides <a 678 href="http://www.explain.com.au/oss/libxml2xslt.html">Mac Os X 679 binaries</a>.</li> 680 <li>The HP-UX porting center provides <a 681 href="http://hpux.connect.org.uk/hppd/hpux/Gnome/">HP-UX binaries</a></li> 682 <li>Bull provides precompiled <a 683 href="http://gnome.bullfreeware.com/new_index.html">RPMs for AIX</a> as 684 patr of their GNOME packages</li> 685</ul> 686 687<p>If you know other supported binary ports, please <a 688href="http://veillard.com/">contact me</a>.</p> 689 690<p><a name="Snapshot">Snapshot:</a></p> 691<ul> 692 <li>Code from the W3C svn base libxml2 module, updated hourly <a 693 href="ftp://xmlsoft.org/libxml2/libxml2-cvs-snapshot.tar.gz">libxml2-cvs-snapshot.tar.gz</a>.</li> 694 <li>Docs, content of the web site, the list archive included <a 695 href="ftp://xmlsoft.org/libxml2/libxml-docs.tar.gz">libxml-docs.tar.gz</a>.</li> 696</ul> 697 698<p><a name="Contribs">Contributions:</a></p> 699 700<p>I do accept external contributions, especially if compiling on another 701platform, get in touch with the list to upload the package, wrappers for 702various languages have been provided, and can be found in the <a 703href="python.html">bindings section</a></p> 704 705<p>Libxml2 is also available from SVN:</p> 706<ul> 707 <li><p>The <a href="http://svn.gnome.org/viewcvs/libxml2/trunk/">Gnome SVN 708 base</a>. Check the <a 709 href="http://developer.gnome.org/tools/svn.html">Gnome SVN Tools</a> 710 page; the SVN module is <b>libxml2</b>.</p> 711 </li> 712 <li>The <strong>libxslt</strong> module is also present there</li> 713</ul> 714 715<h2><a name="News">Releases</a></h2> 716 717<p>Items not finished and worked on, get in touch with the list if you want 718to help those</p> 719<ul> 720 <li>More testing on RelaxNG</li> 721 <li>Finishing up <a href="http://www.w3.org/TR/xmlschema-1/">XML 722 Schemas</a></li> 723</ul> 724 725<p>The <a href="ChangeLog.html">change log</a> describes the recents commits 726to the <a href="http://svn.gnome.org/viewcvs/libxml2/trunk/">SVN</a> code base.</p> 727 728<p>Here is the list of public releases:</p> 729 730<h3>2.7.2: Oct 3 2008</h3> 731<ul> 732 <li>Portability fix: fix solaris compilation problem, fix compilation 733 if XPath is not configured in</li> 734 <li>Bug fixes: nasty entity bug introduced in 2.7.0, restore old behaviour 735 when saving an HTML doc with an xml dump function, HTML UTF-8 parsing 736 bug, fix reader custom error handlers (Riccardo Scussat) 737 <li>Improvement: xmlSave options for more flexibility to save as 738 XML/HTML/XHTML, handle leading BOM in HTML documents</li> 739</ul> 740 741<h3>2.7.1: Sep 1 2008</h3> 742<ul> 743 <li>Portability fix: Borland C fix (Moritz Both)</li> 744 <li>Bug fixes: python serialization wrappers, XPath QName corner 745 case handking and leaks (Martin)</li> 746 <li>Improvement: extend the xmlSave to handle HTML documents and trees</li> 747 <li>Cleanup: python serialization wrappers</li> 748</ul> 749 750<h3>2.7.0: Aug 30 2008</h3> 751<ul> 752 <li>Documentation: switch ChangeLog to UTF-8, improve mutithreads and 753 xmlParserCleanup docs</li> 754 <li>Portability fixes: Older Win32 platforms (Rob Richards), MSVC 755 porting fix (Rob Richards), Mac OS X regression tests (Sven Herzberg), 756 non GNUCC builds (Rob Richards), compilation on Haiku (Andreas F�rber) 757 </li> 758 <li>Bug fixes: various realloc problems (Ashwin), potential double-free 759 (Ashwin), regexp crash, icrash with invalid whitespace facets (Rob 760 Richards), pattern fix when streaming (William Brack), various XML 761 parsing and validation fixes based on the W3C regression tests, reader 762 tree skipping function fix (Ashwin), Schemas regexps escaping fix 763 (Volker Grabsch), handling of entity push errors (Ashwin), fix a slowdown 764 when encoder cant serialize characters on output</li> 765 <li>Code cleanup: compilation fix without the reader, without the output 766 (Robert Schwebel), python whitespace (Martin), many space/tabs cleanups, 767 serious cleanup of the entity handling code</li> 768 <li>Improvement: switch parser to XML-1.0 5th edition, add parsing flags 769 for old versions, switch URI parsing to RFC 3986, 770 add xmlSchemaValidCtxtGetParserCtxt (Holger Kaelberer), 771 new hashing functions for dictionnaries (based on Stefan Behnel work), 772 improve handling of misplaced html/head/body in HTML parser, better 773 regression test tools and code coverage display, better algorithms 774 to detect various versions of the billion laughts attacks, make 775 arbitrary parser limits avoidable as a parser option</li> 776</ul> 777<h3>2.6.32: Apr 8 2008</h3> 778<ul> 779 <li>Documentation: returning heap memory to kernel (Wolfram Sang), 780 trying to clarify xmlCleanupParser() use, xmlXPathContext improvement 781 (Jack Jansen), improve the *Recover* functions documentation, 782 XmlNodeType doc link fix (Martijn Arts)</li> 783 <li>Bug fixes: internal subset memory leak (Ashwin), avoid problem with 784 paths starting with // (Petr Sumbera), streaming XSD validation callback 785 patches (Ashwin), fix redirection on port other than 80 (William Brack), 786 SAX2 leak (Ashwin), XInclude fragment of own document (Chris Ryan), 787 regexp bug with '.' (Andrew Tosh), flush the writer at the end of the 788 document (Alfred Mickautsch), output I/O bug fix (William Brack), 789 writer CDATA output after a text node (Alex Khesin), UTF-16 encoding 790 detection (William Brack), fix handling of empty CDATA nodes for Safari 791 team, python binding problem with namespace nodes, improve HTML parsing 792 (Arnold Hendriks), regexp automata build bug, memory leak fix (Vasily 793 Chekalkin), XSD test crash, weird system parameter entity parsing problem, 794 allow save to file:///X:/ windows paths, various attribute normalisation 795 problems, externalSubsetSplit fix (Ashwin), attribute redefinition in 796 the DTD (Ashwin), fix in char ref parsing check (Alex Khesin), many 797 out of memory handling fixes (Ashwin), XPath out of memory handling fixes 798 (Alvaro Herrera), various realloc problems (Ashwin), UCS4 encoding 799 conversion buffer size (Christian Fruth), problems with EatName 800 functions on memory errors, BOM handling in external parsed entities 801 (Mark Rowe)</li> 802 <li>Code cleanup: fix build under VS 2008 (David Wimsey), remove useless 803 mutex in xmlDict (Florent Guilian), Mingw32 compilation fix (Carlo 804 Bramini), Win and MacOS EOL cleanups (Florent Guiliani), iconv need 805 a const detection (Roumen Petrov), simplify xmlSetProp (Julien Charbon), 806 cross compilation fixes for Mingw (Roumen Petrov), SCO Openserver build 807 fix (Florent Guiliani), iconv uses const on Win32 (Rob Richards), 808 duplicate code removal (Ashwin), missing malloc test and error reports 809 (Ashwin), VMS makefile fix (Tycho Hilhorst)</li> 810 <li>improvements: better plug of schematron in the normal error handling 811 (Tobias Minich)</li> 812</ul> 813 814<h3>2.6.31: Jan 11 2008</h3> 815<ul> 816 <li>Security fix: missing of checks in UTF-8 parsing</li> 817 <li>Bug fixes: regexp bug, dump attribute from XHTML document, fix 818 xmlFree(NULL) to not crash in debug mode, Schematron parsing crash 819 (Rob Richards), global lock free on Windows (Marc-Antoine Ruel), 820 XSD crash due to double free (Rob Richards), indentation fix in 821 xmlTextWriterFullEndElement (Felipe Pena), error in attribute type 822 parsing if attribute redeclared, avoid crash in hash list scanner if 823 deleting elements, column counter bug fix (Christian Schmidt), 824 HTML embed element saving fix (Stefan Behnel), avoid -L/usr/lib 825 output from xml2-config (Fred Crozat), avoid an xmllint crash 826 (Stefan Kost), don't stop HTML parsing on out of range chars. 827 </li> 828 <li>Code cleanup: fix open() call third argument, regexp cut'n paste 829 copy error, unused variable in __xmlGlobalInitMutexLock (Hannes Eder), 830 some make distcheck realted fixes (John Carr)</li> 831 <li>Improvements: HTTP Header: includes port number (William Brack), 832 testURI --debug option, </li> 833</ul> 834<h3>2.6.30: Aug 23 2007</h3> 835<ul> 836 <li>Portability: Solaris crash on error handling, windows path fixes 837 (Roland Schwarz and Rob Richards), mingw build (Roland Schwarz)</li> 838 <li>Bugfixes: xmlXPathNodeSetSort problem (William Brack), leak when 839 reusing a writer for a new document (Dodji Seketeli), Schemas 840 xsi:nil handling patch (Frank Gross), relative URI build problem 841 (Patrik Fimml), crash in xmlDocFormatDump, invalid char in comment 842 detection bug, fix disparity with xmlSAXUserParseMemory, automata 843 generation for complex regexp counts problems, Schemas IDC import 844 problems (Frank Gross), xpath predicate evailation error handling 845 (William Brack)</li> 846</ul> 847<h3>2.6.29: Jun 12 2007</h3> 848<ul> 849 <li>Portability: patches from Andreas Stricke for WinCEi, 850 fix compilation warnings (William Brack), avoid warnings on Apple OS/X 851 (Wendy Doyle and Mark Rowe), Windows compilation and threading 852 improvements (Rob Richards), compilation against old Python versions, 853 new GNU tar changes (Ryan Hill)</li> 854 <li>Documentation: xmlURIUnescapeString comment, </li> 855 <li>Bugfixes: xmlBufferAdd problem (Richard Jones), 'make valgrind' 856 flag fix (Richard Jones), regexp interpretation of \, 857 htmlCreateDocParserCtxt (Jean-Daniel Dupas), configure.in 858 typo (Bjorn Reese), entity content failure, xmlListAppend() fix 859 (Georges-Andr� Silber), XPath number serialization (William Brack), 860 nanohttp gzipped stream fix (William Brack and Alex Cornejo), 861 xmlCharEncFirstLine typo (Mark Rowe), uri bug (Fran�ois Delyon), 862 XPath string value of PI nodes (William Brack), XPath node set 863 sorting bugs (William Brack), avoid outputting namespace decl 864 dups in the writer (Rob Richards), xmlCtxtReset bug, UTF-8 encoding 865 error handling, recustion on next in catalogs, fix a Relax-NG crash, 866 workaround wrong file: URIs, htmlNodeDumpFormatOutput on attributes, 867 invalid character in attribute detection bug, big comments before 868 internal subset streaming bug, HTML parsing of attributes with : in 869 the name, IDness of name in HTML (Dagfinn I. Manns�ker) </li> 870 <li>Improvement: keep URI query parts in raw form (Richard Jones), 871 embed tag support in HTML (Michael Day) </li> 872</ul> 873 874<h3>2.6.28: Apr 17 2007</h3> 875<ul> 876 <li>Documentation: comment fixes (Markus Keim), xpath comments fixes too 877 (James Dennett)</li> 878 <li>Bug fixes: XPath bug (William Brack), HTML parser autoclose stack usage 879 (Usamah Malik), various regexp bug fixes (DV and William), path conversion 880 on Windows (Igor Zlatkovic), htmlCtxtReset fix (Michael Day), XPath 881 principal node of axis bug, HTML serialization of some codepoint 882 (Steven Rainwater), user data propagation in XInclude (Michael Day), 883 standalone and XML decl detection (Michael Day), Python id ouptut 884 for some id, fix the big python string memory leak, URI parsing fixes 885 (St�phane Bidoul and William), long comments parsing bug (William), 886 concurrent threads initialization (Ted Phelps), invalid char 887 in text XInclude (William), XPath memory leak (William), tab in 888 python problems (Andreas Hanke), XPath node comparison error 889 (Oleg Paraschenko), cleanup patch for reader (Julien Reichel), 890 XML Schemas attribute group (William), HTML parsing problem (William), 891 fix char 0x2d in regexps (William), regexp quantifier range with 892 min occurs of 0 (William), HTML script/style parsing (Mike Day)</li> 893 <li>Improvement: make xmlTextReaderSetup() public</li> 894 <li>Compilation and postability: fix a missing include problem (William), 895 __ss_familly on AIX again (Bj�rn Wiberg), compilation without zlib 896 (Michael Day), catalog patch for Win32 (Christian Ehrlicher), 897 Windows CE fixes (Andreas Stricke)</li> 898 <li>Various CVS to SVN infrastructure changes</li> 899</ul> 900<h3>2.6.27: Oct 25 2006</h3> 901<ul> 902 <li>Portability fixes: file names on windows (Roland Schwingel, 903 Emelyanov Alexey), windows compile fixup (Rob Richards), 904 AIX iconv() is apparently case sensitive</li> 905 <li>improvements: Python XPath types mapping (Nic Ferrier), XPath optimization 906 (Kasimier), add xmlXPathCompiledEvalToBoolean (Kasimier), Python node 907 equality and comparison (Andreas Pakulat), xmlXPathCollectAndTest 908 improvememt (Kasimier), expose if library was compiled with zlib 909 support (Andrew Nosenko), cache for xmlSchemaIDCMatcher structs 910 (Kasimier), xmlTextConcat should work with comments and PIs (Rob 911 Richards), export htmlNewParserCtxt needed by Michael Day, refactoring 912 of catalog entity loaders (Michael Day), add XPointer support to 913 python bindings (Ross Reedstrom, Brian West and Stefan Anca), 914 try to sort out most file path to URI conversions and xmlPathToUri, 915 add --html --memory case to xmllint</li> 916 <li>building fix: fix --with-minimum (Felipe Contreras), VMS fix, 917 const'ification of HTML parser structures (Matthias Clasen), 918 portability fix (Emelyanov Alexey), wget autodetection (Peter 919 Breitenlohner), remove the build path recorded in the python 920 shared module, separate library flags for shared and static builds 921 (Mikhail Zabaluev), fix --with-minimum --with-sax1 builds, fix 922 --with-minimum --with-schemas builds</li> 923 <li>bug fix: xmlGetNodePath fix (Kasimier), xmlDOMWrapAdoptNode and 924 attribute (Kasimier), crash when using the recover mode, 925 xmlXPathEvalExpr problem (Kasimier), xmlXPathCompExprAdd bug (Kasimier), 926 missing destry in xmlFreeRMutex (Andrew Nosenko), XML Schemas fixes 927 (Kasimier), warning on entities processing, XHTML script and style 928 serialization (Kasimier), python generator for long types, bug in 929 xmlSchemaClearValidCtxt (Bertrand Fritsch), xmlSchemaXPathEvaluate 930 allocation bug (Marton Illes), error message end of line (Rob Richards), 931 fix attribute serialization in writer (Rob Richards), PHP4 DTD validation 932 crasher, parser safety patch (Ben Darnell), _private context propagation 933 when parsing entities (with Michael Day), fix entities behaviour when 934 using SAX, URI to file path fix (Mikhail Zabaluev), disapearing validity 935 context, arg error in SAX callback (Mike Hommey), fix mixed-content 936 autodetect when using --noblanks, fix xmlIOParseDTD error handling, 937 fix bug in xmlSplitQName on special Names, fix Relax-NG element content 938 validation bug, fix xmlReconciliateNs bug, fix potential attribute 939 XML parsing bug, fix line/column accounting in XML parser, chunking bug 940 in the HTML parser on script, try to detect obviously buggy HTML 941 meta encoding indications, bugs with encoding BOM and xmlSaveDoc, 942 HTML entities in attributes parsing, HTML minimized attribute values, 943 htmlReadDoc and htmlReadIO were broken, error handling bug in 944 xmlXPathEvalExpression (Olaf Walkowiak), fix a problem in 945 htmlCtxtUseOptions, xmlNewInputFromFile could leak (Marius Konitzer), 946 bug on misformed SSD regexps (Christopher Boumenot) 947 </li> 948 <li>documentation: warning about XML_PARSE_COMPACT (Kasimier Buchcik), 949 fix xmlXPathCastToString documentation, improve man pages for 950 xmllitn and xmlcatalog (Daniel Leidert), fixed comments of a few 951 functions</li> 952</ul> 953<h3>2.6.26: Jun 6 2006</h3> 954<ul> 955 <li>portability fixes: Python detection (Joseph Sacco), compilation 956 error(William Brack and Graham Bennett), LynxOS patch (Olli Savia)</li> 957 <li>bug fixes: encoding buffer problem, mix of code and data in 958 xmlIO.c(Kjartan Maraas), entities in XSD validation (Kasimier Buchcik), 959 variousXSD validation fixes (Kasimier), memory leak in pattern (Rob 960 Richards andKasimier), attribute with colon in name (Rob Richards), XPath 961 leak inerror reporting (Aleksey Sanin), XInclude text include of 962 selfdocument.</li> 963 <li>improvements: Xpath optimizations (Kasimier), XPath object 964 cache(Kasimier)</li> 965</ul> 966 967<h3>2.6.25: Jun 6 2006:</h3> 968 969<p>Do not use or package 2.6.25</p> 970 971<h3>2.6.24: Apr 28 2006</h3> 972<ul> 973 <li>Portability fixes: configure on Windows, testapi compile on windows 974 (Kasimier Buchcik, venkat naidu), Borland C++ 6 compile (Eric Zurcher), 975 HP-UX compiler workaround (Rick Jones), xml2-config bugfix, gcc-4.1 976 cleanups, Python detection scheme (Joseph Sacco), UTF-8 file paths on 977 Windows (Roland Schwingel). 978 </li> 979 <li>Improvements: xmlDOMWrapReconcileNamespaces xmlDOMWrapCloneNode (Kasimier 980 Buchcik), XML catalog debugging (Rick Jones), update to Unicode 4.01.</li> 981 <li>Bug fixes: xmlParseChunk() problem in 2.6.23, xmlParseInNodeContext() 982 on HTML docs, URI behaviour on Windows (Rob Richards), comment streaming 983 bug, xmlParseComment (with William Brack), regexp bug fixes (DV & 984 Youri Golovanov), xmlGetNodePath on text/CDATA (Kasimier), 985 one Relax-NG interleave bug, xmllint --path and --valid, 986 XSD bugfixes (Kasimier), remove debug 987 left in Python bindings (Nic Ferrier), xmlCatalogAdd bug (Martin Cole), 988 xmlSetProp fixes (Rob Richards), HTML IDness (Rob Richards), a large 989 number of cleanups and small fixes based on Coverity reports, bug 990 in character ranges, Unicode tables const (Aivars Kalvans), schemas 991 fix (Stefan Kost), xmlRelaxNGParse error deallocation, 992 xmlSchemaAddSchemaDoc error deallocation, error handling on unallowed 993 code point, ixmllint --nonet to never reach the net (Gary Coady), 994 line break in writer after end PI (Jason Viers). </li> 995 <li>Documentation: man pages updates and cleanups (Daniel Leidert).</li> 996 <li>New features: Relax NG structure error handlers.</li> 997</ul> 998 999<h3>2.6.23: Jan 5 2006</h3> 1000<ul> 1001 <li>portability fixes: Windows (Rob Richards), getaddrinfo on Windows 1002 (Kolja Nowak, Rob Richards), icc warnings (Kjartan Maraas), 1003 --with-minimum compilation fixes (William Brack), error case handling fix 1004 on Solaris (Albert Chin), don't use 'list' as parameter name reported by 1005 Samuel Diaz Garcia, more old Unices portability fixes (Albert Chin), 1006 MinGW compilation (Mark Junker), HP-UX compiler warnings (Rick 1007 Jones),</li> 1008 <li>code cleanup: xmlReportError (Adrian Mouat), remove xmlBufferClose 1009 (Geert Jansen), unreachable code (Oleksandr Kononenko), refactoring 1010 parsing code (Bjorn Reese)</li> 1011 <li>bug fixes: xmlBuildRelativeURI and empty path (William Brack), 1012 combinatory explosion and performances in regexp code, leak in 1013 xmlTextReaderReadString(), xmlStringLenDecodeEntities problem (Massimo 1014 Morara), Identity Constraints bugs and a segfault (Kasimier Buchcik), 1015 XPath pattern based evaluation bugs (DV & Kasimier), 1016 xmlSchemaContentModelDump() memory leak (Kasimier), potential leak in 1017 xmlSchemaCheckCSelectorXPath(), xmlTextWriterVSprintf() misuse of 1018 vsnprintf (William Brack), XHTML serialization fix (Rob Richards), CRLF 1019 split problem (William), issues with non-namespaced attributes in 1020 xmlAddChild() xmlAddNextSibling() and xmlAddPrevSibling() (Rob Richards), 1021 HTML parsing of script, Python must not output to stdout (Nic Ferrier), 1022 exclusive C14N namespace visibility (Aleksey Sanin), XSD dataype 1023 totalDigits bug (Kasimier Buchcik), error handling when writing to an 1024 xmlBuffer (Rob Richards), runtest schemas error not reported (Hisashi 1025 Fujinaka), signed/unsigned problem in date/time code (Albert Chin), fix 1026 XSI driven XSD validation (Kasimier), parsing of xs:decimal (Kasimier), 1027 fix DTD writer output (Rob Richards), leak in xmlTextReaderReadInnerXml 1028 (Gary Coady), regexp bug affecting schemas (Kasimier), configuration of 1029 runtime debugging (Kasimier), xmlNodeBufGetContent bug on entity refs 1030 (Oleksandr Kononenko), xmlRegExecPushString2 bug (Sreeni Nair), 1031 compilation and build fixes (Michael Day), removed dependancies on 1032 xmlSchemaValidError (Kasimier), bug with <xml:foo/>, more XPath 1033 pattern based evaluation fixes (Kasimier)</li> 1034 <li>improvements: XSD Schemas redefinitions/restrictions (Kasimier 1035 Buchcik), node copy checks and fix for attribute (Rob Richards), counted 1036 transition bug in regexps, ctxt->standalone = -2 to indicate no 1037 standalone attribute was found, add xmlSchemaSetParserStructuredErrors() 1038 (Kasimier Buchcik), add xmlTextReaderSchemaValidateCtxt() to API 1039 (Kasimier), handle gzipped HTTP resources (Gary Coady), add 1040 htmlDocDumpMemoryFormat. (Rob Richards),</li> 1041 <li>documentation: typo (Michael Day), libxml man page (Albert Chin), save 1042 function to XML buffer (Geert Jansen), small doc fix (Aron Stansvik),</li> 1043</ul> 1044 1045<h3>2.6.22: Sep 12 2005</h3> 1046<ul> 1047 <li>build fixes: compile without schematron (St�phane Bidoul)</li> 1048 <li>bug fixes: xmlDebugDumpNode on namespace node (Oleg Paraschenko)i, 1049 CDATA push parser bug, xmlElemDump problem with XHTML1 doc, 1050 XML_FEATURE_xxx clash with expat headers renamed XML_WITH_xxx, fix some 1051 output formatting for meta element (Rob Richards), script and style 1052 XHTML1 serialization (David Madore), Attribute derivation fixups in XSD 1053 (Kasimier Buchcik), better IDC error reports (Kasimier Buchcik)</li> 1054 <li>improvements: add XML_SAVE_NO_EMPTY xmlSaveOption (Rob Richards), add 1055 XML_SAVE_NO_XHTML xmlSaveOption, XML Schemas improvements preparing for 1056 derive (Kasimier Buchcik).</li> 1057 <li>documentation: generation of gtk-doc like docs, integration with 1058 devhelp.</li> 1059</ul> 1060 1061<h3>2.6.21: Sep 4 2005</h3> 1062<ul> 1063 <li>build fixes: Cygwin portability fixes (Gerrit P. Haase), calling 1064 convention problems on Windows (Marcus Boerger), cleanups based on Linus' 1065 sparse tool, update of win32/configure.js (Rob Richards), remove warnings 1066 on Windows(Marcus Boerger), compilation without SAX1, detection of the 1067 Python binary, use $GCC inestad of $CC = 'gcc' (Andrew W. Nosenko), 1068 compilation/link with threads and old gcc, compile problem by C370 on 1069 Z/OS,</li> 1070 <li>bug fixes: http_proxy environments (Peter Breitenlohner), HTML UTF-8 1071 bug (Jiri Netolicky), XPath NaN compare bug (William Brack), 1072 htmlParseScript potential bug, Schemas regexp handling of spaces, Base64 1073 Schemas comparisons NIST passes, automata build error xsd:all, 1074 xmlGetNodePath for namespaced attributes (Alexander Pohoyda), xmlSchemas 1075 foreign namespaces handling, XML Schemas facet comparison (Kupriyanov 1076 Anatolij), xmlSchemaPSimpleTypeErr error report (Kasimier Buchcik), xml: 1077 namespace ahndling in Schemas (Kasimier), empty model group in Schemas 1078 (Kasimier), wilcard in Schemas (Kasimier), URI composition (William), 1079 xs:anyType in Schemas (Kasimier), Python resolver emmitting error 1080 messages directly, Python xmlAttr.parent (Jakub Piotr Clapa), trying to 1081 fix the file path/URI conversion, xmlTextReaderGetAttribute fix (Rob 1082 Richards), xmlSchemaFreeAnnot memleak (Kasimier), HTML UTF-8 1083 serialization, streaming XPath, Schemas determinism detection problem, 1084 XInclude bug, Schemas context type (Dean Hill), validation fix (Derek 1085 Poon), xmlTextReaderGetAttribute[Ns] namespaces (Rob Richards), Schemas 1086 type fix (Kuba Nowakowski), UTF-8 parser bug, error in encoding handling, 1087 xmlGetLineNo fixes, bug on entities handling, entity name extraction in 1088 error handling with XInclude, text nodes in HTML body tags (Gary Coady), 1089 xml:id and IDness at the treee level fixes, XPath streaming patterns 1090 bugs.</li> 1091 <li>improvements: structured interfaces for schemas and RNG error reports 1092 (Marcus Boerger), optimization of the char data inner loop parsing 1093 (thanks to Behdad Esfahbod for the idea), schematron validation though 1094 not finished yet, xmlSaveOption to omit XML declaration, keyref match 1095 error reports (Kasimier), formal expression handling code not plugged 1096 yet, more lax mode for the HTML parser, parser XML_PARSE_COMPACT option 1097 for text nodes allocation.</li> 1098 <li>documentation: xmllint man page had --nonet duplicated</li> 1099</ul> 1100 1101<h3>2.6.20: Jul 10 2005</h3> 1102<ul> 1103 <li>build fixes: Windows build (Rob Richards), Mingw compilation (Igor 1104 Zlatkovic), Windows Makefile (Igor), gcc warnings (Kasimier and 1105 andriy@google.com), use gcc weak references to pthread to avoid the 1106 pthread dependancy on Linux, compilation problem (Steve Nairn), compiling 1107 of subset (Morten Welinder), IPv6/ss_family compilation (William Brack), 1108 compilation when disabling parts of the library, standalone test 1109 distribution.</li> 1110 <li>bug fixes: bug in lang(), memory cleanup on errors (William Brack), 1111 HTTP query strings (Aron Stansvik), memory leak in DTD (William), integer 1112 overflow in XPath (William), nanoftp buffer size, pattern "." apth fixup 1113 (Kasimier), leak in tree reported by Malcolm Rowe, replaceNode patch 1114 (Brent Hendricks), CDATA with NULL content (Mark Vakoc), xml:base fixup 1115 on XInclude (William), pattern fixes (William), attribute bug in 1116 exclusive c14n (Aleksey Sanin), xml:space and xml:lang with SAX2 (Rob 1117 Richards), namespace trouble in complex parsing (Malcolm Rowe), XSD type 1118 QNames fixes (Kasimier), XPath streaming fixups (William), RelaxNG bug 1119 (Rob Richards), Schemas for Schemas fixes (Kasimier), removal of ID (Rob 1120 Richards), a small RelaxNG leak, HTML parsing in push mode bug (James 1121 Bursa), failure to detect UTF-8 parsing bugs in CDATA sections, 1122 areBlanks() heuristic failure, duplicate attributes in DTD bug 1123 (William).</li> 1124 <li>improvements: lot of work on Schemas by Kasimier Buchcik both on 1125 conformance and streaming, Schemas validation messages (Kasimier Buchcik, 1126 Matthew Burgess), namespace removal at the python level (Brent 1127 Hendricks), Update to new Schemas regression tests from W3C/Nist 1128 (Kasimier), xmlSchemaValidateFile() (Kasimier), implementation of 1129 xmlTextReaderReadInnerXml and xmlTextReaderReadOuterXml (James Wert), 1130 standalone test framework and programs, new DOM import APIs 1131 xmlDOMWrapReconcileNamespaces() xmlDOMWrapAdoptNode() and 1132 xmlDOMWrapRemoveNode(), extension of xmllint capabilities for SAX and 1133 Schemas regression tests, xmlStopParser() available in pull mode too, 1134 ienhancement to xmllint --shell namespaces support, Windows port of the 1135 standalone testing tools (Kasimier and William), 1136 xmlSchemaValidateStream() xmlSchemaSAXPlug() and xmlSchemaSAXUnplug() SAX 1137 Schemas APIs, Schemas xmlReader support.</li> 1138</ul> 1139 1140<h3>2.6.19: Apr 02 2005</h3> 1141<ul> 1142 <li>build fixes: drop .la from RPMs, --with-minimum build fix (William 1143 Brack), use XML_SOCKLEN_T instead of SOCKLEN_T because it breaks with AIX 1144 5.3 compiler, fixed elfgcchack.h generation and PLT reduction code on 1145 Linux/ELF/gcc4</li> 1146 <li>bug fixes: schemas type decimal fixups (William Brack), xmmlint return 1147 code (Gerry Murphy), small schemas fixes (Matthew Burgess and GUY 1148 Fabrice), workaround "DAV:" namespace brokeness in c14n (Aleksey Sanin), 1149 segfault in Schemas (Kasimier Buchcik), Schemas attribute validation 1150 (Kasimier), Prop related functions and xmlNewNodeEatName (Rob Richards), 1151 HTML serialization of name attribute on a elements, Python error handlers 1152 leaks and improvement (Brent Hendricks), uninitialized variable in 1153 encoding code, Relax-NG validation bug, potential crash if 1154 gnorableWhitespace is NULL, xmlSAXParseDoc and xmlParseDoc signatures, 1155 switched back to assuming UTF-8 in case no encoding is given at 1156 serialization time</li> 1157 <li>improvements: lot of work on Schemas by Kasimier Buchcik on facets 1158 checking and also mixed handling.</li> 1159 <li></li> 1160</ul> 1161 1162<h3>2.6.18: Mar 13 2005</h3> 1163<ul> 1164 <li>build fixes: warnings (Peter Breitenlohner), testapi.c generation, 1165 Bakefile support (Francesco Montorsi), Windows compilation (Joel Reed), 1166 some gcc4 fixes, HP-UX portability fixes (Rick Jones).</li> 1167 <li>bug fixes: xmlSchemaElementDump namespace (Kasimier Buchcik), push and 1168 xmlreader stopping on non-fatal errors, thread support for dictionnaries 1169 reference counting (Gary Coady), internal subset and push problem, URL 1170 saved in xmlCopyDoc, various schemas bug fixes (Kasimier), Python paths 1171 fixup (Stephane Bidoul), xmlGetNodePath and namespaces, xmlSetNsProp fix 1172 (Mike Hommey), warning should not count as error (William Brack), 1173 xmlCreatePushParser empty chunk, XInclude parser flags (William), cleanup 1174 FTP and HTTP code to reuse the uri parsing and IPv6 (William), 1175 xmlTextWriterStartAttributeNS fix (Rob Richards), XMLLINT_INDENT being 1176 empty (William), xmlWriter bugs (Rob Richards), multithreading on Windows 1177 (Rich Salz), xmlSearchNsByHref fix (Kasimier), Python binding leak (Brent 1178 Hendricks), aliasing bug exposed by gcc4 on s390, xmlTextReaderNext bug 1179 (Rob Richards), Schemas decimal type fixes (William Brack), 1180 xmlByteConsumed static buffer (Ben Maurer).</li> 1181 <li>improvement: speedup parsing comments and DTDs, dictionnary support for 1182 hash tables, Schemas Identity constraints (Kasimier), streaming XPath 1183 subset, xmlTextReaderReadString added (Bjorn Reese), Schemas canonical 1184 values handling (Kasimier), add xmlTextReaderByteConsumed (Aron 1185 Stansvik),</li> 1186 <li>Documentation: Wiki support (Joel Reed)</li> 1187</ul> 1188 1189<h3>2.6.17: Jan 16 2005</h3> 1190<ul> 1191 <li>build fixes: Windows, warnings removal (William Brack), 1192 maintainer-clean dependency(William), build in a different directory 1193 (William), fixing --with-minimum configure build (William), BeOS build 1194 (Marcin Konicki), Python-2.4 detection (William), compilation on AIX (Dan 1195 McNichol)</li> 1196 <li>bug fixes: xmlTextReaderHasAttributes (Rob Richards), xmlCtxtReadFile() 1197 to use the catalog(s), loop on output (William Brack), XPath memory leak, 1198 ID deallocation problem (Steve Shepard), debugDumpNode crash (William), 1199 warning not using error callback (William), xmlStopParser bug (William), 1200 UTF-16 with BOM on DTDs (William), namespace bug on empty elements in 1201 push mode (Rob Richards), line and col computations fixups (Aleksey 1202 Sanin), xmlURIEscape fix (William), xmlXPathErr on bad range (William), 1203 patterns with too many steps, bug in RNG choice optimization, line number 1204 sometimes missing.</li> 1205 <li>improvements: XSD Schemas (Kasimier Buchcik), python generator 1206 (William), xmlUTF8Strpos speedup (William), unicode Python strings 1207 (William), XSD error reports (Kasimier Buchcik), Python __str__ call 1208 serialize().</li> 1209 <li>new APIs: added xmlDictExists(), GetLineNumber and GetColumnNumber for 1210 the xmlReader (Aleksey Sanin), Dynamic Shared Libraries APIs (mostly Joel 1211 Reed), error extraction API from regexps, new XMLSave option for format 1212 (Phil Shafer)</li> 1213 <li>documentation: site improvement (John Fleck), FAQ entries 1214 (William).</li> 1215</ul> 1216 1217<h3>2.6.16: Nov 10 2004</h3> 1218<ul> 1219 <li>general hardening and bug fixing crossing all the API based on new 1220 automated regression testing</li> 1221 <li>build fix: IPv6 build and test on AIX (Dodji Seketeli)</li> 1222 <li>bug fixes: problem with XML::Libxml reported by Petr Pajas, encoding 1223 conversion functions return values, UTF-8 bug affecting XPath reported by 1224 Markus Bertheau, catalog problem with NULL entries (William Brack)</li> 1225 <li>documentation: fix to xmllint man page, some API function descritpion 1226 were updated.</li> 1227 <li>improvements: DTD validation APIs provided at the Python level (Brent 1228 Hendricks)</li> 1229</ul> 1230 1231<h3>2.6.15: Oct 27 2004</h3> 1232<ul> 1233 <li>security fixes on the nanoftp and nanohttp modules</li> 1234 <li>build fixes: xmllint detection bug in configure, building outside the 1235 source tree (Thomas Fitzsimmons)</li> 1236 <li>bug fixes: HTML parser on broken ASCII chars in names (William), Python 1237 paths (Malcolm Tredinnick), xmlHasNsProp and default namespace (William), 1238 saving to python file objects (Malcolm Tredinnick), DTD lookup fix 1239 (Malcolm), save back <group> in catalogs (William), tree build 1240 fixes (DV and Rob Richards), Schemas memory bug, structured error handler 1241 on Python 64bits, thread local memory deallocation, memory leak reported 1242 by Volker Roth, xmlValidateDtd in the presence of an internal subset, 1243 entities and _private problem (William), xmlBuildRelativeURI error 1244 (William).</li> 1245 <li>improvements: better XInclude error reports (William), tree debugging 1246 module and tests, convenience functions at the Reader API (Graham 1247 Bennett), add support for PI in the HTML parser.</li> 1248</ul> 1249 1250<h3>2.6.14: Sep 29 2004</h3> 1251<ul> 1252 <li>build fixes: configure paths for xmllint and xsltproc, compilation 1253 without HTML parser, compilation warning cleanups (William Brack & 1254 Malcolm Tredinnick), VMS makefile update (Craig Berry),</li> 1255 <li>bug fixes: xmlGetUTF8Char (William Brack), QName properties (Kasimier 1256 Buchcik), XInclude testing, Notation serialization, UTF8ToISO8859x 1257 transcoding (Mark Itzcovitz), lots of XML Schemas cleanup and fixes 1258 (Kasimier), ChangeLog cleanup (Stepan Kasal), memory fixes (Mark Vakoc), 1259 handling of failed realloc(), out of bound array adressing in Schemas 1260 date handling, Python space/tabs cleanups (Malcolm Tredinnick), NMTOKENS 1261 E20 validation fix (Malcolm),</li> 1262 <li>improvements: added W3C XML Schemas testsuite (Kasimier Buchcik), add 1263 xmlSchemaValidateOneElement (Kasimier), Python exception hierearchy 1264 (Malcolm Tredinnick), Python libxml2 driver improvement (Malcolm 1265 Tredinnick), Schemas support for xsi:schemaLocation, 1266 xsi:noNamespaceSchemaLocation, xsi:type (Kasimier Buchcik)</li> 1267</ul> 1268 1269<h3>2.6.13: Aug 31 2004</h3> 1270<ul> 1271 <li>build fixes: Windows and zlib (Igor Zlatkovic), -O flag with gcc, 1272 Solaris compiler warning, fixing RPM BuildRequires,</li> 1273 <li>fixes: DTD loading on Windows (Igor), Schemas error reports APIs 1274 (Kasimier Buchcik), Schemas validation crash, xmlCheckUTF8 (William Brack 1275 and Julius Mittenzwei), Schemas facet check (Kasimier), default namespace 1276 problem (William), Schemas hexbinary empty values, encoding error could 1277 genrate a serialization loop.</li> 1278 <li>Improvements: Schemas validity improvements (Kasimier), added --path 1279 and --load-trace options to xmllint</li> 1280 <li>documentation: tutorial update (John Fleck)</li> 1281</ul> 1282 1283<h3>2.6.12: Aug 22 2004</h3> 1284<ul> 1285 <li>build fixes: fix --with-minimum, elfgcchack.h fixes (Peter 1286 Breitenlohner), perl path lookup (William), diff on Solaris (Albert 1287 Chin), some 64bits cleanups.</li> 1288 <li>Python: avoid a warning with 2.3 (William Brack), tab and space mixes 1289 (William), wrapper generator fixes (William), Cygwin support (Gerrit P. 1290 Haase), node wrapper fix (Marc-Antoine Parent), XML Schemas support 1291 (Torkel Lyng)</li> 1292 <li>Schemas: a lot of bug fixes and improvements from Kasimier Buchcik</li> 1293 <li>fixes: RVT fixes (William), XPath context resets bug (William), memory 1294 debug (Steve Hay), catalog white space handling (Peter Breitenlohner), 1295 xmlReader state after attribute reading (William), structured error 1296 handler (William), XInclude generated xml:base fixup (William), Windows 1297 memory reallocation problem (Steve Hay), Out of Memory conditions 1298 handling (William and Olivier Andrieu), htmlNewDoc() charset bug, 1299 htmlReadMemory init (William), a posteriori validation DTD base 1300 (William), notations serialization missing, xmlGetNodePath (Dodji), 1301 xmlCheckUTF8 (Diego Tartara), missing line numbers on entity 1302 (William)</li> 1303 <li>improvements: DocBook catalog build scrip (William), xmlcatalog tool 1304 (Albert Chin), xmllint --c14n option, no_proxy environment (Mike Hommey), 1305 xmlParseInNodeContext() addition, extend xmllint --shell, allow XInclude 1306 to not generate start/end nodes, extend xmllint --version to include CVS 1307 tag (William)</li> 1308 <li>documentation: web pages fixes, validity API docs fixes (William) 1309 schemas API fix (Eric Haszlakiewicz), xmllint man page (John Fleck)</li> 1310</ul> 1311 1312<h3>2.6.11: July 5 2004</h3> 1313<ul> 1314 <li>Schemas: a lot of changes and improvements by Kasimier Buchcik for 1315 attributes, namespaces and simple types.</li> 1316 <li>build fixes: --with-minimum (William Brack), some gcc cleanup 1317 (William), --with-thread-alloc (William)</li> 1318 <li>portability: Windows binary package change (Igor Zlatkovic), Catalog 1319 path on Windows</li> 1320 <li>documentation: update to the tutorial (John Fleck), xmllint return code 1321 (John Fleck), man pages (Ville Skytta),</li> 1322 <li>bug fixes: C14N bug serializing namespaces (Aleksey Sanin), testSAX 1323 properly initialize the library (William), empty node set in XPath 1324 (William), xmlSchemas errors (William), invalid charref problem pointed 1325 by Morus Walter, XInclude xml:base generation (William), Relax-NG bug 1326 with div processing (William), XPointer and xml:base problem(William), 1327 Reader and entities, xmllint return code for schemas (William), reader 1328 streaming problem (Steve Ball), DTD serialization problem (William), 1329 libxml.m4 fixes (Mike Hommey), do not provide destructors as methods on 1330 Python classes, xmlReader buffer bug, Python bindings memory interfaces 1331 improvement (with St�phane Bidoul), Fixed the push parser to be back to 1332 synchronous behaviour.</li> 1333 <li>improvement: custom per-thread I/O enhancement (Rob Richards), register 1334 namespace in debug shell (Stefano Debenedetti), Python based regression 1335 test for non-Unix users (William), dynamically increase the number of 1336 XPath extension functions in Python and fix a memory leak (Marc-Antoine 1337 Parent and William)</li> 1338 <li>performance: hack done with Arjan van de Ven to reduce ELF footprint 1339 and generated code on Linux, plus use gcc runtime profiling to optimize 1340 the code generated in the RPM packages.</li> 1341</ul> 1342 1343<h3>2.6.10: May 17 2004</h3> 1344<ul> 1345 <li>Web page generated for ChangeLog</li> 1346 <li>build fixes: --without-html problems, make check without make all</li> 1347 <li>portability: problem with xpath.c on Windows (MSC and Borland), memcmp 1348 vs. strncmp on Solaris, XPath tests on Windows (Mark Vakoc), C++ do not 1349 use "list" as parameter name, make tests work with Python 1.5 (Ed 1350 Davis),</li> 1351 <li>improvements: made xmlTextReaderMode public, small buffers resizing 1352 (Morten Welinder), add --maxmem option to xmllint, add 1353 xmlPopInputCallback() for Matt Sergeant, refactoring of serialization 1354 escaping, added escaping customization</li> 1355 <li>bugfixes: xsd:extension (Taihei Goi), assorted regexp bugs (William 1356 Brack), xmlReader end of stream problem, node deregistration with reader, 1357 URI escaping and filemanes, XHTML1 formatting (Nick Wellnhofer), regexp 1358 transition reduction (William), various XSD Schemas fixes (Kasimier 1359 Buchcik), XInclude fallback problem (William), weird problems with DTD 1360 (William), structured error handler callback context (William), reverse 1361 xmlEncodeSpecialChars() behaviour back to escaping '"'</li> 1362</ul> 1363 1364<h3>2.6.9: Apr 18 2004</h3> 1365<ul> 1366 <li>implement xml:id Working Draft, relaxed XPath id() checking</li> 1367 <li>bugfixes: xmlCtxtReset (Brent Hendricks), line number and CDATA (Dave 1368 Beckett), Relax-NG compilation (William Brack), Regexp patches (with 1369 William), xmlUriEscape (Mark Vakoc), a Relax-NG notAllowed problem (with 1370 William), Relax-NG name classes compares (William), XInclude duplicate 1371 fallback (William), external DTD encoding detection (William), a DTD 1372 validation bug (William), xmlReader Close() fix, recusive extention 1373 schemas</li> 1374 <li>improvements: use xmlRead* APIs in test tools (Mark Vakoc), indenting 1375 save optimization, better handle IIS broken HTTP redirect behaviour (Ian 1376 Hummel), HTML parser frameset (James Bursa), libxml2-python RPM 1377 dependancy, XML Schemas union support (Kasimier Buchcik), warning removal 1378 clanup (William), keep ChangeLog compressed when installing from RPMs</li> 1379 <li>documentation: examples and xmlDocDumpMemory docs (John Fleck), new 1380 example (load, xpath, modify, save), xmlCatalogDump() comments,</li> 1381 <li>Windows: Borland C++ builder (Eric Zurcher), work around Microsoft 1382 compiler NaN handling bug (Mark Vakoc)</li> 1383</ul> 1384 1385<h3>2.6.8: Mar 23 2004</h3> 1386<ul> 1387 <li>First step of the cleanup of the serialization code and APIs</li> 1388 <li>XML Schemas: mixed content (Adam Dickmeiss), QName handling fixes (Adam 1389 Dickmeiss), anyURI for "" (John Belmonte)</li> 1390 <li>Python: Canonicalization C14N support added (Anthony Carrico)</li> 1391 <li>xmlDocCopyNode() extension (William)</li> 1392 <li>Relax-NG: fix when processing XInclude results (William), external 1393 reference in interleave (William), missing error on <choice> 1394 failure (William), memory leak in schemas datatype facets.</li> 1395 <li>xmlWriter: patch for better DTD support (Alfred Mickautsch)</li> 1396 <li>bug fixes: xmlXPathLangFunction memory leak (Mike Hommey and William 1397 Brack), no ID errors if using HTML_PARSE_NOERROR, xmlcatalog fallbacks to 1398 URI on SYSTEM lookup failure, XInclude parse flags inheritance (William), 1399 XInclude and XPointer fixes for entities (William), XML parser bug 1400 reported by Holger Rauch, nanohttp fd leak (William), regexps char 1401 groups '-' handling (William), dictionnary reference counting problems, 1402 do not close stderr.</li> 1403 <li>performance patches from Petr Pajas</li> 1404 <li>Documentation fixes: XML_CATALOG_FILES in man pages (Mike Hommey)</li> 1405 <li>compilation and portability fixes: --without-valid, catalog cleanups 1406 (Peter Breitenlohner), MingW patch (Roland Schwingel), cross-compilation 1407 to Windows (Christophe de Vienne), --with-html-dir fixup (Julio Merino 1408 Vidal), Windows build (Eric Zurcher)</li> 1409</ul> 1410 1411<h3>2.6.7: Feb 23 2004</h3> 1412<ul> 1413 <li>documentation: tutorial updates (John Fleck), benchmark results</li> 1414 <li>xmlWriter: updates and fixes (Alfred Mickautsch, Lucas Brasilino)</li> 1415 <li>XPath optimization (Petr Pajas)</li> 1416 <li>DTD ID handling optimization</li> 1417 <li>bugfixes: xpath number with > 19 fractional (William Brack), push 1418 mode with unescaped '>' characters, fix xmllint --stream --timing, fix 1419 xmllint --memory --stream memory usage, xmlAttrSerializeTxtContent 1420 handling NULL, trying to fix Relax-NG/Perl interface.</li> 1421 <li>python: 2.3 compatibility, whitespace fixes (Malcolm Tredinnick)</li> 1422 <li>Added relaxng option to xmllint --shell</li> 1423</ul> 1424 1425<h3>2.6.6: Feb 12 2004</h3> 1426<ul> 1427 <li>nanohttp and nanoftp: buffer overflow error on URI parsing (Igor and 1428 William) reported by Yuuichi Teranishi</li> 1429 <li>bugfixes: make test and path issues, xmlWriter attribute serialization 1430 (William Brack), xmlWriter indentation (William), schemas validation 1431 (Eric Haszlakiewicz), XInclude dictionnaries issues (William and Oleg 1432 Paraschenko), XInclude empty fallback (William), HTML warnings (William), 1433 XPointer in XInclude (William), Python namespace serialization, 1434 isolat1ToUTF8 bound error (Alfred Mickautsch), output of parameter 1435 entities in internal subset (William), internal subset bug in push mode, 1436 <xs:all> fix (Alexey Sarytchev)</li> 1437 <li>Build: fix for automake-1.8 (Alexander Winston), warnings removal 1438 (Philip Ludlam), SOCKLEN_T detection fixes (Daniel Richard), fix 1439 --with-minimum configuration.</li> 1440 <li>XInclude: allow the 2001 namespace without warning.</li> 1441 <li>Documentation: missing example/index.html (John Fleck), version 1442 dependancies (John Fleck)</li> 1443 <li>reader API: structured error reporting (Steve Ball)</li> 1444 <li>Windows compilation: mingw, msys (Mikhail Grushinskiy), function 1445 prototype (Cameron Johnson), MSVC6 compiler warnings, _WINSOCKAPI_ 1446 patch</li> 1447 <li>Parsers: added xmlByteConsumed(ctxt) API to get the byte offest in 1448 input.</li> 1449</ul> 1450 1451<h3>2.6.5: Jan 25 2004</h3> 1452<ul> 1453 <li>Bugfixes: dictionnaries for schemas (William Brack), regexp segfault 1454 (William), xs:all problem (William), a number of XPointer bugfixes 1455 (William), xmllint error go to stderr, DTD validation problem with 1456 namespace, memory leak (William), SAX1 cleanup and minimal options fixes 1457 (Mark Vadoc), parser context reset on error (Shaun McCance), XPath union 1458 evaluation problem (William) , xmlReallocLoc with NULL (Aleksey Sanin), 1459 XML Schemas double free (Steve Ball), XInclude with no href, argument 1460 callbacks order for XPath callbacks (Frederic Peters)</li> 1461 <li>Documentation: python scripts (William Brack), xslt stylesheets (John 1462 Fleck), doc (Sven Zimmerman), I/O example.</li> 1463 <li>Python bindings: fixes (William), enum support (St�phane Bidoul), 1464 structured error reporting (St�phane Bidoul)</li> 1465 <li>XInclude: various fixes for conformance, problem related to dictionnary 1466 references (William & me), recursion (William)</li> 1467 <li>xmlWriter: indentation (Lucas Brasilino), memory leaks (Alfred 1468 Mickautsch),</li> 1469 <li>xmlSchemas: normalizedString datatype (John Belmonte)</li> 1470 <li>code cleanup for strings functions (William)</li> 1471 <li>Windows: compiler patches (Mark Vakoc)</li> 1472 <li>Parser optimizations, a few new XPath and dictionnary APIs for future 1473 XSLT optimizations.</li> 1474</ul> 1475 1476<h3>2.6.4: Dec 24 2003</h3> 1477<ul> 1478 <li>Windows build fixes (Igor Zlatkovic)</li> 1479 <li>Some serious XInclude problems reported by Oleg Paraschenko and</li> 1480 <li>Unix and Makefile packaging fixes (me, William Brack,</li> 1481 <li>Documentation improvements (John Fleck, William Brack), example fix 1482 (Lucas Brasilino)</li> 1483 <li>bugfixes: xmlTextReaderExpand() with xmlReaderWalker, XPath handling of 1484 NULL strings (William Brack) , API building reader or parser from 1485 filedescriptor should not close it, changed XPath sorting to be stable 1486 again (William Brack), xmlGetNodePath() generating '(null)' (William 1487 Brack), DTD validation and namespace bug (William Brack), XML Schemas 1488 double inclusion behaviour</li> 1489</ul> 1490 1491<h3>2.6.3: Dec 10 2003</h3> 1492<ul> 1493 <li>documentation updates and cleanup (DV, William Brack, John Fleck)</li> 1494 <li>added a repository of examples, examples from Aleksey Sanin, Dodji 1495 Seketeli, Alfred Mickautsch</li> 1496 <li>Windows updates: Mark Vakoc, Igor Zlatkovic, Eric Zurcher, Mingw 1497 (Kenneth Haley)</li> 1498 <li>Unicode range checking (William Brack)</li> 1499 <li>code cleanup (William Brack)</li> 1500 <li>Python bindings: doc (John Fleck), bug fixes</li> 1501 <li>UTF-16 cleanup and BOM issues (William Brack)</li> 1502 <li>bug fixes: ID and xmlReader validation, XPath (William Brack), 1503 xmlWriter (Alfred Mickautsch), hash.h inclusion problem, HTML parser 1504 (James Bursa), attribute defaulting and validation, some serialization 1505 cleanups, XML_GET_LINE macro, memory debug when using threads (William 1506 Brack), serialization of attributes and entities content, xmlWriter 1507 (Daniel Schulman)</li> 1508 <li>XInclude bugfix, new APIs and update to the last version including the 1509 namespace change.</li> 1510 <li>XML Schemas improvements: include (Robert Stepanek), import and 1511 namespace handling, fixed the regression tests troubles, added examples 1512 based on Eric van der Vlist book, regexp fixes</li> 1513 <li>preliminary pattern support for streaming (needed for schemas 1514 constraints), added xmlTextReaderPreservePattern() to collect subdocument 1515 when streaming.</li> 1516 <li>various fixes in the structured error handling</li> 1517</ul> 1518 1519<h3>2.6.2: Nov 4 2003</h3> 1520<ul> 1521 <li>XPath context unregistration fixes</li> 1522 <li>text node coalescing fixes (Mark Lilback)</li> 1523 <li>API to screate a W3C Schemas from an existing document (Steve Ball)</li> 1524 <li>BeOS patches (Marcin 'Shard' Konicki)</li> 1525 <li>xmlStrVPrintf function added (Aleksey Sanin)</li> 1526 <li>compilation fixes (Mark Vakoc)</li> 1527 <li>stdin parsing fix (William Brack)</li> 1528 <li>a posteriori DTD validation fixes</li> 1529 <li>xmlReader bug fixes: Walker fixes, python bindings</li> 1530 <li>fixed xmlStopParser() to really stop the parser and errors</li> 1531 <li>always generate line numbers when using the new xmlReadxxx 1532 functions</li> 1533 <li>added XInclude support to the xmlReader interface</li> 1534 <li>implemented XML_PARSE_NONET parser option</li> 1535 <li>DocBook XSLT processing bug fixed</li> 1536 <li>HTML serialization for <p> elements (William Brack and me)</li> 1537 <li>XPointer failure in XInclude are now handled as resource errors</li> 1538 <li>fixed xmllint --html to use the HTML serializer on output (added 1539 --xmlout to implement the previous behaviour of saving it using the XML 1540 serializer)</li> 1541</ul> 1542 1543<h3>2.6.1: Oct 28 2003</h3> 1544<ul> 1545 <li>Mostly bugfixes after the big 2.6.0 changes</li> 1546 <li>Unix compilation patches: libxml.m4 (Patrick Welche), warnings cleanup 1547 (William Brack)</li> 1548 <li>Windows compilation patches (Joachim Bauch, Stephane Bidoul, Igor 1549 Zlatkovic)</li> 1550 <li>xmlWriter bugfix (Alfred Mickautsch)</li> 1551 <li>chvalid.[ch]: couple of fixes from Stephane Bidoul</li> 1552 <li>context reset: error state reset, push parser reset (Graham 1553 Bennett)</li> 1554 <li>context reuse: generate errors if file is not readable</li> 1555 <li>defaulted attributes for element coming from internal entities 1556 (Stephane Bidoul)</li> 1557 <li>Python: tab and spaces mix (William Brack)</li> 1558 <li>Error handler could crash in DTD validation in 2.6.0</li> 1559 <li>xmlReader: do not use the document or element _private field</li> 1560 <li>testSAX.c: avoid a problem with some PIs (Massimo Morara)</li> 1561 <li>general bug fixes: mandatory encoding in text decl, serializing 1562 Document Fragment nodes, xmlSearchNs 2.6.0 problem (Kasimier Buchcik), 1563 XPath errors not reported, slow HTML parsing of large documents.</li> 1564</ul> 1565 1566<h3>2.6.0: Oct 20 2003</h3> 1567<ul> 1568 <li>Major revision release: should be API and ABI compatible but got a lot 1569 of change</li> 1570 <li>Increased the library modularity, far more options can be stripped out, 1571 a --with-minimum configuration will weight around 160KBytes</li> 1572 <li>Use per parser and per document dictionnary, allocate names and small 1573 text nodes from the dictionnary</li> 1574 <li>Switch to a SAX2 like parser rewrote most of the XML parser core, 1575 provides namespace resolution and defaulted attributes, minimize memory 1576 allocations and copies, namespace checking and specific error handling, 1577 immutable buffers, make predefined entities static structures, etc...</li> 1578 <li>rewrote all the error handling in the library, all errors can be 1579 intercepted at a structured level, with precise information 1580 available.</li> 1581 <li>New simpler and more generic XML and HTML parser APIs, allowing to 1582 easilly modify the parsing options and reuse parser context for multiple 1583 consecutive documents.</li> 1584 <li>Similar new APIs for the xmlReader, for options and reuse, provided new 1585 functions to access content as const strings, use them for Python 1586 bindings</li> 1587 <li>a lot of other smaller API improvements: xmlStrPrintf (Aleksey Sanin), 1588 Walker i.e. reader on a document tree based on Alfred Mickautsch code, 1589 make room in nodes for line numbers, reference counting and future PSVI 1590 extensions, generation of character ranges to be checked with faster 1591 algorithm (William), xmlParserMaxDepth (Crutcher Dunnavant), buffer 1592 access</li> 1593 <li>New xmlWriter API provided by Alfred Mickautsch</li> 1594 <li>Schemas: base64 support by Anthony Carrico</li> 1595 <li>Parser<->HTTP integration fix, proper processing of the Mime-Type 1596 and charset information if available.</li> 1597 <li>Relax-NG: bug fixes including the one reported by Martijn Faassen and 1598 zeroOrMore, better error reporting.</li> 1599 <li>Python bindings (St�phane Bidoul), never use stdout for errors 1600 output</li> 1601 <li>Portability: all the headers have macros for export and calling 1602 convention definitions (Igor Zlatkovic), VMS update (Craig A. Berry), 1603 Windows: threads (Jesse Pelton), Borland compiler (Eric Zurcher, Igor), 1604 Mingw (Igor), typos (Mark Vakoc), beta version (Stephane Bidoul), 1605 warning cleanups on AIX and MIPS compilers (William Brack), BeOS (Marcin 1606 'Shard' Konicki)</li> 1607 <li>Documentation fixes and README (William Brack), search fix (William), 1608 tutorial updates (John Fleck), namespace docs (Stefan Kost)</li> 1609 <li>Bug fixes: xmlCleanupParser (Dave Beckett), threading uninitialized 1610 mutexes, HTML doctype lowercase, SAX/IO (William), compression detection 1611 and restore (William), attribute declaration in DTDs (William), namespace 1612 on attribute in HTML output (William), input filename (Rob Richards), 1613 namespace DTD validation, xmlReplaceNode (Chris Ryland), I/O callbacks 1614 (Markus Keim), CDATA serialization (Shaun McCance), xmlReader (Peter 1615 Derr), high codepoint charref like &#x10FFFF;, buffer access in push 1616 mode (Justin Fletcher), TLS threads on Windows (Jesse Pelton), XPath bug 1617 (William), xmlCleanupParser (Marc Liyanage), CDATA output (William), HTTP 1618 error handling.</li> 1619 <li>xmllint options: --dtdvalidfpi for Tobias Reif, --sax1 for compat 1620 testing, --nodict for building without tree dictionnary, --nocdata to 1621 replace CDATA by text, --nsclean to remove surperfluous namespace 1622 declarations</li> 1623 <li>added xml2-config --libtool-libs option from Kevin P. Fleming</li> 1624 <li>a lot of profiling and tuning of the code, speedup patch for 1625 xmlSearchNs() by Luca Padovani. The xmlReader should do far less 1626 allocation and it speed should get closer to SAX. Chris Anderson worked 1627 on speeding and cleaning up repetitive checking code.</li> 1628 <li>cleanup of "make tests"</li> 1629 <li>libxml-2.0-uninstalled.pc from Malcolm Tredinnick</li> 1630 <li>deactivated the broken docBook SGML parser code and plugged the XML 1631 parser instead.</li> 1632</ul> 1633 1634<h3>2.5.11: Sep 9 2003</h3> 1635 1636<p>A bugfix only release:</p> 1637<ul> 1638 <li>risk of crash in Relax-NG</li> 1639 <li>risk of crash when using multithreaded programs</li> 1640</ul> 1641 1642<h3>2.5.10: Aug 15 2003</h3> 1643 1644<p>A bugfixes only release</p> 1645<ul> 1646 <li>Windows Makefiles (William Brack)</li> 1647 <li>UTF-16 support fixes (Mark Itzcovitz)</li> 1648 <li>Makefile and portability (William Brack) automake, Linux alpha, Mingw 1649 on Windows (Mikhail Grushinskiy)</li> 1650 <li>HTML parser (Oliver Stoeneberg)</li> 1651 <li>XInclude performance problem reported by Kevin Ruscoe</li> 1652 <li>XML parser performance problem reported by Grant Goodale</li> 1653 <li>xmlSAXParseDTD() bug fix from Malcolm Tredinnick</li> 1654 <li>and a couple other cleanup</li> 1655</ul> 1656 1657<h3>2.5.9: Aug 9 2003</h3> 1658<ul> 1659 <li>bugfixes: IPv6 portability, xmlHasNsProp (Markus Keim), Windows build 1660 (Wiliam Brake, Jesse Pelton, Igor), Schemas (Peter Sobisch), threading 1661 (Rob Richards), hexBinary type (), UTF-16 BOM (Dodji Seketeli), 1662 xmlReader, Relax-NG schemas compilation, namespace handling, EXSLT (Sean 1663 Griffin), HTML parsing problem (William Brack), DTD validation for mixed 1664 content + namespaces, HTML serialization, library initialization, 1665 progressive HTML parser</li> 1666 <li>better interfaces for Relax-NG error handling (Joachim Bauch, )</li> 1667 <li>adding xmlXIncludeProcessTree() for XInclud'ing in a subtree</li> 1668 <li>doc fixes and improvements (John Fleck)</li> 1669 <li>configure flag for -with-fexceptions when embedding in C++</li> 1670 <li>couple of new UTF-8 helper functions (William Brack)</li> 1671 <li>general encoding cleanup + ISO-8859-x without iconv (Peter Jacobi)</li> 1672 <li>xmlTextReader cleanup + enum for node types (Bjorn Reese)</li> 1673 <li>general compilation/warning cleanup Solaris/HP-UX/... (William 1674 Brack)</li> 1675</ul> 1676 1677<h3>2.5.8: Jul 6 2003</h3> 1678<ul> 1679 <li>bugfixes: XPath, XInclude, file/URI mapping, UTF-16 save (Mark 1680 Itzcovitz), UTF-8 checking, URI saving, error printing (William Brack), 1681 PI related memleak, compilation without schemas or without xpath (Joerg 1682 Schmitz-Linneweber/Garry Pennington), xmlUnlinkNode problem with DTDs, 1683 rpm problem on , i86_64, removed a few compilation problems from 2.5.7, 1684 xmlIOParseDTD, and xmlSAXParseDTD (Malcolm Tredinnick)</li> 1685 <li>portability: DJGPP (MsDos) , OpenVMS (Craig A. Berry)</li> 1686 <li>William Brack fixed multithreading lock problems</li> 1687 <li>IPv6 patch for FTP and HTTP accesses (Archana Shah/Wipro)</li> 1688 <li>Windows fixes (Igor Zlatkovic, Eric Zurcher), threading (St�phane 1689 Bidoul)</li> 1690 <li>A few W3C Schemas Structure improvements</li> 1691 <li>W3C Schemas Datatype improvements (Charlie Bozeman)</li> 1692 <li>Python bindings for thread globals (St�phane Bidoul), and method/class 1693 generator</li> 1694 <li>added --nonet option to xmllint</li> 1695 <li>documentation improvements (John Fleck)</li> 1696</ul> 1697 1698<h3>2.5.7: Apr 25 2003</h3> 1699<ul> 1700 <li>Relax-NG: Compiling to regexp and streaming validation on top of the 1701 xmlReader interface, added to xmllint --stream</li> 1702 <li>xmlReader: Expand(), Next() and DOM access glue, bug fixes</li> 1703 <li>Support for large files: RGN validated a 4.5GB instance</li> 1704 <li>Thread support is now configured in by default</li> 1705 <li>Fixes: update of the Trio code (Bjorn), WXS Date and Duration fixes 1706 (Charles Bozeman), DTD and namespaces (Brent Hendricks), HTML push parser 1707 and zero bytes handling, some missing Windows file path conversions, 1708 behaviour of the parser and validator in the presence of "out of memory" 1709 error conditions</li> 1710 <li>extended the API to be able to plug a garbage collecting memory 1711 allocator, added xmlMallocAtomic() and modified the allocations 1712 accordingly.</li> 1713 <li>Performances: removed excessive malloc() calls, speedup of the push and 1714 xmlReader interfaces, removed excessive thread locking</li> 1715 <li>Documentation: man page (John Fleck), xmlReader documentation</li> 1716 <li>Python: adding binding for xmlCatalogAddLocal (Brent M Hendricks)</li> 1717</ul> 1718 1719<h3>2.5.6: Apr 1 2003</h3> 1720<ul> 1721 <li>Fixed W3C XML Schemas datatype, should be compliant now except for 1722 binHex and base64 which are not supported yet.</li> 1723 <li>bug fixes: non-ASCII IDs, HTML output, XInclude on large docs and 1724 XInclude entities handling, encoding detection on external subsets, XML 1725 Schemas bugs and memory leaks, HTML parser (James Bursa)</li> 1726 <li>portability: python/trio (Albert Chin), Sun compiler warnings</li> 1727 <li>documentation: added --relaxng option to xmllint man page (John)</li> 1728 <li>improved error reporting: xml:space, start/end tag mismatches, Relax NG 1729 errors</li> 1730</ul> 1731 1732<h3>2.5.5: Mar 24 2003</h3> 1733<ul> 1734 <li>Lot of fixes on the Relax NG implementation. More testing including 1735 DocBook and TEI examples.</li> 1736 <li>Increased the support for W3C XML Schemas datatype</li> 1737 <li>Several bug fixes in the URI handling layer</li> 1738 <li>Bug fixes: HTML parser, xmlReader, DTD validation, XPath, encoding 1739 conversion, line counting in the parser.</li> 1740 <li>Added support for $XMLLINT_INDENT environment variable, FTP delete</li> 1741 <li>Fixed the RPM spec file name</li> 1742</ul> 1743 1744<h3>2.5.4: Feb 20 2003</h3> 1745<ul> 1746 <li>Conformance testing and lot of fixes on Relax NG and XInclude 1747 implementation</li> 1748 <li>Implementation of XPointer element() scheme</li> 1749 <li>Bug fixes: XML parser, XInclude entities merge, validity checking on 1750 namespaces, 1751 <p>2 serialization bugs, node info generation problems, a DTD regexp 1752 generation problem.</p> 1753 </li> 1754 <li>Portability: windows updates and path canonicalization (Igor)</li> 1755 <li>A few typo fixes (Kjartan Maraas)</li> 1756 <li>Python bindings generator fixes (Stephane Bidoul)</li> 1757</ul> 1758 1759<h3>2.5.3: Feb 10 2003</h3> 1760<ul> 1761 <li>RelaxNG and XML Schemas datatypes improvements, and added a first 1762 version of RelaxNG Python bindings</li> 1763 <li>Fixes: XLink (Sean Chittenden), XInclude (Sean Chittenden), API fix for 1764 serializing namespace nodes, encoding conversion bug, XHTML1 1765 serialization</li> 1766 <li>Portability fixes: Windows (Igor), AMD 64bits RPM spec file</li> 1767</ul> 1768 1769<h3>2.5.2: Feb 5 2003</h3> 1770<ul> 1771 <li>First implementation of RelaxNG, added --relaxng flag to xmllint</li> 1772 <li>Schemas support now compiled in by default.</li> 1773 <li>Bug fixes: DTD validation, namespace checking, XInclude and entities, 1774 delegateURI in XML Catalogs, HTML parser, XML reader (St�phane Bidoul), 1775 XPath parser and evaluation, UTF8ToUTF8 serialization, XML reader memory 1776 consumption, HTML parser, HTML serialization in the presence of 1777 namespaces</li> 1778 <li>added an HTML API to check elements and attributes.</li> 1779 <li>Documentation improvement, PDF for the tutorial (John Fleck), doc 1780 patches (Stefan Kost)</li> 1781 <li>Portability fixes: NetBSD (Julio Merino), Windows (Igor Zlatkovic)</li> 1782 <li>Added python bindings for XPointer, contextual error reporting 1783 (St�phane Bidoul)</li> 1784 <li>URI/file escaping problems (Stefano Zacchiroli)</li> 1785</ul> 1786 1787<h3>2.5.1: Jan 8 2003</h3> 1788<ul> 1789 <li>Fixes a memory leak and configuration/compilation problems in 2.5.0</li> 1790 <li>documentation updates (John)</li> 1791 <li>a couple of XmlTextReader fixes</li> 1792</ul> 1793 1794<h3>2.5.0: Jan 6 2003</h3> 1795<ul> 1796 <li>New <a href="xmlreader.html">XmltextReader interface</a> based on C# 1797 API (with help of St�phane Bidoul)</li> 1798 <li>Windows: more exports, including the new API (Igor)</li> 1799 <li>XInclude fallback fix</li> 1800 <li>Python: bindings for the new API, packaging (St�phane Bidoul), 1801 drv_libxml2.py Python xml.sax driver (St�phane Bidoul), fixes, speedup 1802 and iterators for Python-2.2 (Hannu Krosing)</li> 1803 <li>Tutorial fixes (john Fleck and Niraj Tolia) xmllint man update 1804 (John)</li> 1805 <li>Fix an XML parser bug raised by Vyacheslav Pindyura</li> 1806 <li>Fix for VMS serialization (Nigel Hall) and config (Craig A. Berry)</li> 1807 <li>Entities handling fixes</li> 1808 <li>new API to optionally track node creation and deletion (Lukas 1809 Schroeder)</li> 1810 <li>Added documentation for the XmltextReader interface and some <a 1811 href="guidelines.html">XML guidelines</a></li> 1812</ul> 1813 1814<h3>2.4.30: Dec 12 2002</h3> 1815<ul> 1816 <li>2.4.29 broke the python bindings, rereleasing</li> 1817 <li>Improvement/fixes of the XML API generator, and couple of minor code 1818 fixes.</li> 1819</ul> 1820 1821<h3>2.4.29: Dec 11 2002</h3> 1822<ul> 1823 <li>Windows fixes (Igor): Windows CE port, pthread linking, python bindings 1824 (St�phane Bidoul), Mingw (Magnus Henoch), and export list updates</li> 1825 <li>Fix for prev in python bindings (ERDI Gergo)</li> 1826 <li>Fix for entities handling (Marcus Clarke)</li> 1827 <li>Refactored the XML and HTML dumps to a single code path, fixed XHTML1 1828 dump</li> 1829 <li>Fix for URI parsing when handling URNs with fragment identifiers</li> 1830 <li>Fix for HTTP URL escaping problem</li> 1831 <li>added an TextXmlReader (C#) like API (work in progress)</li> 1832 <li>Rewrote the API in XML generation script, includes a C parser and saves 1833 more information needed for C# bindings</li> 1834</ul> 1835 1836<h3>2.4.28: Nov 22 2002</h3> 1837<ul> 1838 <li>a couple of python binding fixes</li> 1839 <li>2 bug fixes in the XML push parser</li> 1840 <li>potential memory leak removed (Martin Stoilov)</li> 1841 <li>fix to the configure script for Unix (Dimitri Papadopoulos)</li> 1842 <li>added encoding support for XInclude parse="text"</li> 1843 <li>autodetection of XHTML1 and specific serialization rules added</li> 1844 <li>nasty threading bug fixed (William Brack)</li> 1845</ul> 1846 1847<h3>2.4.27: Nov 17 2002</h3> 1848<ul> 1849 <li>fixes for the Python bindings</li> 1850 <li>a number of bug fixes: SGML catalogs, xmlParseBalancedChunkMemory(), 1851 HTML parser, Schemas (Charles Bozeman), document fragment support 1852 (Christian Glahn), xmlReconciliateNs (Brian Stafford), XPointer, 1853 xmlFreeNode(), xmlSAXParseMemory (Peter Jones), xmlGetNodePath (Petr 1854 Pajas), entities processing</li> 1855 <li>added grep to xmllint --shell</li> 1856 <li>VMS update patch from Craig A. Berry</li> 1857 <li>cleanup of the Windows build with support for more compilers (Igor), 1858 better thread support on Windows</li> 1859 <li>cleanup of Unix Makefiles and spec file</li> 1860 <li>Improvements to the documentation (John Fleck)</li> 1861</ul> 1862 1863<h3>2.4.26: Oct 18 2002</h3> 1864<ul> 1865 <li>Patches for Windows CE port, improvements on Windows paths handling</li> 1866 <li>Fixes to the validation code (DTD and Schemas), xmlNodeGetPath() , 1867 HTML serialization, Namespace compliance, and a number of small 1868 problems</li> 1869</ul> 1870 1871<h3>2.4.25: Sep 26 2002</h3> 1872<ul> 1873 <li>A number of bug fixes: XPath, validation, Python bindings, DOM and 1874 tree, xmlI/O, Html</li> 1875 <li>Serious rewrite of XInclude</li> 1876 <li>Made XML Schemas regexp part of the default build and APIs, small fix 1877 and improvement of the regexp core</li> 1878 <li>Changed the validation code to reuse XML Schemas regexp APIs</li> 1879 <li>Better handling of Windows file paths, improvement of Makefiles (Igor, 1880 Daniel Gehriger, Mark Vakoc)</li> 1881 <li>Improved the python I/O bindings, the tests, added resolver and regexp 1882 APIs</li> 1883 <li>New logos from Marc Liyanage</li> 1884 <li>Tutorial improvements: John Fleck, Christopher Harris</li> 1885 <li>Makefile: Fixes for AMD x86_64 (Mandrake), DESTDIR (Christophe 1886 Merlet)</li> 1887 <li>removal of all stderr/perror use for error reporting</li> 1888 <li>Better error reporting: XPath and DTD validation</li> 1889 <li>update of the trio portability layer (Bjorn Reese)</li> 1890</ul> 1891 1892<p><strong>2.4.24: Aug 22 2002</strong></p> 1893<ul> 1894 <li>XPath fixes (William), xf:escape-uri() (Wesley Terpstra)</li> 1895 <li>Python binding fixes: makefiles (William), generator, rpm build, x86-64 1896 (fcrozat)</li> 1897 <li>HTML <style> and boolean attributes serializer fixes</li> 1898 <li>C14N improvements by Aleksey</li> 1899 <li>doc cleanups: Rick Jones</li> 1900 <li>Windows compiler makefile updates: Igor and Elizabeth Barham</li> 1901 <li>XInclude: implementation of fallback and xml:base fixup added</li> 1902</ul> 1903 1904<h3>2.4.23: July 6 2002</h3> 1905<ul> 1906 <li>performances patches: Peter Jacobi</li> 1907 <li>c14n fixes, testsuite and performances: Aleksey Sanin</li> 1908 <li>added xmlDocFormatDump: Chema Celorio</li> 1909 <li>new tutorial: John Fleck</li> 1910 <li>new hash functions and performances: Sander Vesik, portability fix from 1911 Peter Jacobi</li> 1912 <li>a number of bug fixes: XPath (William Brack, Richard Jinks), XML and 1913 HTML parsers, ID lookup function</li> 1914 <li>removal of all remaining sprintf: Aleksey Sanin</li> 1915</ul> 1916 1917<h3>2.4.22: May 27 2002</h3> 1918<ul> 1919 <li>a number of bug fixes: configure scripts, base handling, parser, memory 1920 usage, HTML parser, XPath, documentation (Christian Cornelssen), 1921 indentation, URI parsing</li> 1922 <li>Optimizations for XMLSec, fixing and making public some of the network 1923 protocol handlers (Aleksey)</li> 1924 <li>performance patch from Gary Pennington</li> 1925 <li>Charles Bozeman provided date and time support for XML Schemas 1926 datatypes</li> 1927</ul> 1928 1929<h3>2.4.21: Apr 29 2002</h3> 1930 1931<p>This release is both a bug fix release and also contains the early XML 1932Schemas <a href="http://www.w3.org/TR/xmlschema-1/">structures</a> and <a 1933href="http://www.w3.org/TR/xmlschema-2/">datatypes</a> code, beware, all 1934interfaces are likely to change, there is huge holes, it is clearly a work in 1935progress and don't even think of putting this code in a production system, 1936it's actually not compiled in by default. The real fixes are:</p> 1937<ul> 1938 <li>a couple of bugs or limitations introduced in 2.4.20</li> 1939 <li>patches for Borland C++ and MSC by Igor</li> 1940 <li>some fixes on XPath strings and conformance patches by Richard 1941 Jinks</li> 1942 <li>patch from Aleksey for the ExcC14N specification</li> 1943 <li>OSF/1 bug fix by Bjorn</li> 1944</ul> 1945 1946<h3>2.4.20: Apr 15 2002</h3> 1947<ul> 1948 <li>bug fixes: file descriptor leak, XPath, HTML output, DTD validation</li> 1949 <li>XPath conformance testing by Richard Jinks</li> 1950 <li>Portability fixes: Solaris, MPE/iX, Windows, OSF/1, python bindings, 1951 libxml.m4</li> 1952</ul> 1953 1954<h3>2.4.19: Mar 25 2002</h3> 1955<ul> 1956 <li>bug fixes: half a dozen XPath bugs, Validation, ISO-Latin to UTF8 1957 encoder</li> 1958 <li>portability fixes in the HTTP code</li> 1959 <li>memory allocation checks using valgrind, and profiling tests</li> 1960 <li>revamp of the Windows build and Makefiles</li> 1961</ul> 1962 1963<h3>2.4.18: Mar 18 2002</h3> 1964<ul> 1965 <li>bug fixes: tree, SAX, canonicalization, validation, portability, 1966 XPath</li> 1967 <li>removed the --with-buffer option it was becoming unmaintainable</li> 1968 <li>serious cleanup of the Python makefiles</li> 1969 <li>speedup patch to XPath very effective for DocBook stylesheets</li> 1970 <li>Fixes for Windows build, cleanup of the documentation</li> 1971</ul> 1972 1973<h3>2.4.17: Mar 8 2002</h3> 1974<ul> 1975 <li>a lot of bug fixes, including "namespace nodes have no parents in 1976 XPath"</li> 1977 <li>fixed/improved the Python wrappers, added more examples and more 1978 regression tests, XPath extension functions can now return node-sets</li> 1979 <li>added the XML Canonicalization support from Aleksey Sanin</li> 1980</ul> 1981 1982<h3>2.4.16: Feb 20 2002</h3> 1983<ul> 1984 <li>a lot of bug fixes, most of them were triggered by the XML Testsuite 1985 from OASIS and W3C. Compliance has been significantly improved.</li> 1986 <li>a couple of portability fixes too.</li> 1987</ul> 1988 1989<h3>2.4.15: Feb 11 2002</h3> 1990<ul> 1991 <li>Fixed the Makefiles, especially the python module ones</li> 1992 <li>A few bug fixes and cleanup</li> 1993 <li>Includes cleanup</li> 1994</ul> 1995 1996<h3>2.4.14: Feb 8 2002</h3> 1997<ul> 1998 <li>Change of License to the <a 1999 href="http://www.opensource.org/licenses/mit-license.html">MIT 2000 License</a> basically for integration in XFree86 codebase, and removing 2001 confusion around the previous dual-licensing</li> 2002 <li>added Python bindings, beta software but should already be quite 2003 complete</li> 2004 <li>a large number of fixes and cleanups, especially for all tree 2005 manipulations</li> 2006 <li>cleanup of the headers, generation of a reference API definition in 2007 XML</li> 2008</ul> 2009 2010<h3>2.4.13: Jan 14 2002</h3> 2011<ul> 2012 <li>update of the documentation: John Fleck and Charlie Bozeman</li> 2013 <li>cleanup of timing code from Justin Fletcher</li> 2014 <li>fixes for Windows and initial thread support on Win32: Igor and Serguei 2015 Narojnyi</li> 2016 <li>Cygwin patch from Robert Collins</li> 2017 <li>added xmlSetEntityReferenceFunc() for Keith Isdale work on xsldbg</li> 2018</ul> 2019 2020<h3>2.4.12: Dec 7 2001</h3> 2021<ul> 2022 <li>a few bug fixes: thread (Gary Pennington), xmllint (Geert Kloosterman), 2023 XML parser (Robin Berjon), XPointer (Danny Jamshy), I/O cleanups 2024 (robert)</li> 2025 <li>Eric Lavigne contributed project files for MacOS</li> 2026 <li>some makefiles cleanups</li> 2027</ul> 2028 2029<h3>2.4.11: Nov 26 2001</h3> 2030<ul> 2031 <li>fixed a couple of errors in the includes, fixed a few bugs, some code 2032 cleanups</li> 2033 <li>xmllint man pages improvement by Heiko Rupp</li> 2034 <li>updated VMS build instructions from John A Fotheringham</li> 2035 <li>Windows Makefiles updates from Igor</li> 2036</ul> 2037 2038<h3>2.4.10: Nov 10 2001</h3> 2039<ul> 2040 <li>URI escaping fix (Joel Young)</li> 2041 <li>added xmlGetNodePath() (for paths or XPointers generation)</li> 2042 <li>Fixes namespace handling problems when using DTD and validation</li> 2043 <li>improvements on xmllint: Morus Walter patches for --format and 2044 --encode, Stefan Kost and Heiko Rupp improvements on the --shell</li> 2045 <li>fixes for xmlcatalog linking pointed by Weiqi Gao</li> 2046 <li>fixes to the HTML parser</li> 2047</ul> 2048 2049<h3>2.4.9: Nov 6 2001</h3> 2050<ul> 2051 <li>fixes more catalog bugs</li> 2052 <li>avoid a compilation problem, improve xmlGetLineNo()</li> 2053</ul> 2054 2055<h3>2.4.8: Nov 4 2001</h3> 2056<ul> 2057 <li>fixed SGML catalogs broken in previous release, updated xmlcatalog 2058 tool</li> 2059 <li>fixed a compile errors and some includes troubles.</li> 2060</ul> 2061 2062<h3>2.4.7: Oct 30 2001</h3> 2063<ul> 2064 <li>exported some debugging interfaces</li> 2065 <li>serious rewrite of the catalog code</li> 2066 <li>integrated Gary Pennington thread safety patch, added configure option 2067 and regression tests</li> 2068 <li>removed an HTML parser bug</li> 2069 <li>fixed a couple of potentially serious validation bugs</li> 2070 <li>integrated the SGML DocBook support in xmllint</li> 2071 <li>changed the nanoftp anonymous login passwd</li> 2072 <li>some I/O cleanup and a couple of interfaces for Perl wrapper</li> 2073 <li>general bug fixes</li> 2074 <li>updated xmllint man page by John Fleck</li> 2075 <li>some VMS and Windows updates</li> 2076</ul> 2077 2078<h3>2.4.6: Oct 10 2001</h3> 2079<ul> 2080 <li>added an updated man pages by John Fleck</li> 2081 <li>portability and configure fixes</li> 2082 <li>an infinite loop on the HTML parser was removed (William)</li> 2083 <li>Windows makefile patches from Igor</li> 2084 <li>fixed half a dozen bugs reported for libxml or libxslt</li> 2085 <li>updated xmlcatalog to be able to modify SGML super catalogs</li> 2086</ul> 2087 2088<h3>2.4.5: Sep 14 2001</h3> 2089<ul> 2090 <li>Remove a few annoying bugs in 2.4.4</li> 2091 <li>forces the HTML serializer to output decimal charrefs since some 2092 version of Netscape can't handle hexadecimal ones</li> 2093</ul> 2094 2095<h3>1.8.16: Sep 14 2001</h3> 2096<ul> 2097 <li>maintenance release of the old libxml1 branch, couple of bug and 2098 portability fixes</li> 2099</ul> 2100 2101<h3>2.4.4: Sep 12 2001</h3> 2102<ul> 2103 <li>added --convert to xmlcatalog, bug fixes and cleanups of XML 2104 Catalog</li> 2105 <li>a few bug fixes and some portability changes</li> 2106 <li>some documentation cleanups</li> 2107</ul> 2108 2109<h3>2.4.3: Aug 23 2001</h3> 2110<ul> 2111 <li>XML Catalog support see the doc</li> 2112 <li>New NaN/Infinity floating point code</li> 2113 <li>A few bug fixes</li> 2114</ul> 2115 2116<h3>2.4.2: Aug 15 2001</h3> 2117<ul> 2118 <li>adds xmlLineNumbersDefault() to control line number generation</li> 2119 <li>lot of bug fixes</li> 2120 <li>the Microsoft MSC projects files should now be up to date</li> 2121 <li>inheritance of namespaces from DTD defaulted attributes</li> 2122 <li>fixes a serious potential security bug</li> 2123 <li>added a --format option to xmllint</li> 2124</ul> 2125 2126<h3>2.4.1: July 24 2001</h3> 2127<ul> 2128 <li>possibility to keep line numbers in the tree</li> 2129 <li>some computation NaN fixes</li> 2130 <li>extension of the XPath API</li> 2131 <li>cleanup for alpha and ia64 targets</li> 2132 <li>patch to allow saving through HTTP PUT or POST</li> 2133</ul> 2134 2135<h3>2.4.0: July 10 2001</h3> 2136<ul> 2137 <li>Fixed a few bugs in XPath, validation, and tree handling.</li> 2138 <li>Fixed XML Base implementation, added a couple of examples to the 2139 regression tests</li> 2140 <li>A bit of cleanup</li> 2141</ul> 2142 2143<h3>2.3.14: July 5 2001</h3> 2144<ul> 2145 <li>fixed some entities problems and reduce memory requirement when 2146 substituting them</li> 2147 <li>lots of improvements in the XPath queries interpreter can be 2148 substantially faster</li> 2149 <li>Makefiles and configure cleanups</li> 2150 <li>Fixes to XPath variable eval, and compare on empty node set</li> 2151 <li>HTML tag closing bug fixed</li> 2152 <li>Fixed an URI reference computation problem when validating</li> 2153</ul> 2154 2155<h3>2.3.13: June 28 2001</h3> 2156<ul> 2157 <li>2.3.12 configure.in was broken as well as the push mode XML parser</li> 2158 <li>a few more fixes for compilation on Windows MSC by Yon Derek</li> 2159</ul> 2160 2161<h3>1.8.14: June 28 2001</h3> 2162<ul> 2163 <li>Zbigniew Chyla gave a patch to use the old XML parser in push mode</li> 2164 <li>Small Makefile fix</li> 2165</ul> 2166 2167<h3>2.3.12: June 26 2001</h3> 2168<ul> 2169 <li>lots of cleanup</li> 2170 <li>a couple of validation fix</li> 2171 <li>fixed line number counting</li> 2172 <li>fixed serious problems in the XInclude processing</li> 2173 <li>added support for UTF8 BOM at beginning of entities</li> 2174 <li>fixed a strange gcc optimizer bugs in xpath handling of float, gcc-3.0 2175 miscompile uri.c (William), Thomas Leitner provided a fix for the 2176 optimizer on Tru64</li> 2177 <li>incorporated Yon Derek and Igor Zlatkovic fixes and improvements for 2178 compilation on Windows MSC</li> 2179 <li>update of libxml-doc.el (Felix Natter)</li> 2180 <li>fixed 2 bugs in URI normalization code</li> 2181</ul> 2182 2183<h3>2.3.11: June 17 2001</h3> 2184<ul> 2185 <li>updates to trio, Makefiles and configure should fix some portability 2186 problems (alpha)</li> 2187 <li>fixed some HTML serialization problems (pre, script, and block/inline 2188 handling), added encoding aware APIs, cleanup of this code</li> 2189 <li>added xmlHasNsProp()</li> 2190 <li>implemented a specific PI for encoding support in the DocBook SGML 2191 parser</li> 2192 <li>some XPath fixes (-Infinity, / as a function parameter and namespaces 2193 node selection)</li> 2194 <li>fixed a performance problem and an error in the validation code</li> 2195 <li>fixed XInclude routine to implement the recursive behaviour</li> 2196 <li>fixed xmlFreeNode problem when libxml is included statically twice</li> 2197 <li>added --version to xmllint for bug reports</li> 2198</ul> 2199 2200<h3>2.3.10: June 1 2001</h3> 2201<ul> 2202 <li>fixed the SGML catalog support</li> 2203 <li>a number of reported bugs got fixed, in XPath, iconv detection, 2204 XInclude processing</li> 2205 <li>XPath string function should now handle unicode correctly</li> 2206</ul> 2207 2208<h3>2.3.9: May 19 2001</h3> 2209 2210<p>Lots of bugfixes, and added a basic SGML catalog support:</p> 2211<ul> 2212 <li>HTML push bugfix #54891 and another patch from Jonas Borgstr�m</li> 2213 <li>some serious speed optimization again</li> 2214 <li>some documentation cleanups</li> 2215 <li>trying to get better linking on Solaris (-R)</li> 2216 <li>XPath API cleanup from Thomas Broyer</li> 2217 <li>Validation bug fixed #54631, added a patch from Gary Pennington, fixed 2218 xmlValidGetValidElements()</li> 2219 <li>Added an INSTALL file</li> 2220 <li>Attribute removal added to API: #54433</li> 2221 <li>added a basic support for SGML catalogs</li> 2222 <li>fixed xmlKeepBlanksDefault(0) API</li> 2223 <li>bugfix in xmlNodeGetLang()</li> 2224 <li>fixed a small configure portability problem</li> 2225 <li>fixed an inversion of SYSTEM and PUBLIC identifier in HTML document</li> 2226</ul> 2227 2228<h3>1.8.13: May 14 2001</h3> 2229<ul> 2230 <li>bugfixes release of the old libxml1 branch used by Gnome</li> 2231</ul> 2232 2233<h3>2.3.8: May 3 2001</h3> 2234<ul> 2235 <li>Integrated an SGML DocBook parser for the Gnome project</li> 2236 <li>Fixed a few things in the HTML parser</li> 2237 <li>Fixed some XPath bugs raised by XSLT use, tried to fix the floating 2238 point portability issue</li> 2239 <li>Speed improvement (8M/s for SAX, 3M/s for DOM, 1.5M/s for 2240 DOM+validation using the XML REC as input and a 700MHz celeron).</li> 2241 <li>incorporated more Windows cleanup</li> 2242 <li>added xmlSaveFormatFile()</li> 2243 <li>fixed problems in copying nodes with entities references (gdome)</li> 2244 <li>removed some troubles surrounding the new validation module</li> 2245</ul> 2246 2247<h3>2.3.7: April 22 2001</h3> 2248<ul> 2249 <li>lots of small bug fixes, corrected XPointer</li> 2250 <li>Non deterministic content model validation support</li> 2251 <li>added xmlDocCopyNode for gdome2</li> 2252 <li>revamped the way the HTML parser handles end of tags</li> 2253 <li>XPath: corrections of namespaces support and number formatting</li> 2254 <li>Windows: Igor Zlatkovic patches for MSC compilation</li> 2255 <li>HTML output fixes from P C Chow and William M. Brack</li> 2256 <li>Improved validation speed sensible for DocBook</li> 2257 <li>fixed a big bug with ID declared in external parsed entities</li> 2258 <li>portability fixes, update of Trio from Bjorn Reese</li> 2259</ul> 2260 2261<h3>2.3.6: April 8 2001</h3> 2262<ul> 2263 <li>Code cleanup using extreme gcc compiler warning options, found and 2264 cleared half a dozen potential problem</li> 2265 <li>the Eazel team found an XML parser bug</li> 2266 <li>cleaned up the user of some of the string formatting function. used the 2267 trio library code to provide the one needed when the platform is missing 2268 them</li> 2269 <li>xpath: removed a memory leak and fixed the predicate evaluation 2270 problem, extended the testsuite and cleaned up the result. XPointer seems 2271 broken ...</li> 2272</ul> 2273 2274<h3>2.3.5: Mar 23 2001</h3> 2275<ul> 2276 <li>Biggest change is separate parsing and evaluation of XPath expressions, 2277 there is some new APIs for this too</li> 2278 <li>included a number of bug fixes(XML push parser, 51876, notations, 2279 52299)</li> 2280 <li>Fixed some portability issues</li> 2281</ul> 2282 2283<h3>2.3.4: Mar 10 2001</h3> 2284<ul> 2285 <li>Fixed bugs #51860 and #51861</li> 2286 <li>Added a global variable xmlDefaultBufferSize to allow default buffer 2287 size to be application tunable.</li> 2288 <li>Some cleanup in the validation code, still a bug left and this part 2289 should probably be rewritten to support ambiguous content model :-\</li> 2290 <li>Fix a couple of serious bugs introduced or raised by changes in 2.3.3 2291 parser</li> 2292 <li>Fixed another bug in xmlNodeGetContent()</li> 2293 <li>Bjorn fixed XPath node collection and Number formatting</li> 2294 <li>Fixed a loop reported in the HTML parsing</li> 2295 <li>blank space are reported even if the Dtd content model proves that they 2296 are formatting spaces, this is for XML conformance</li> 2297</ul> 2298 2299<h3>2.3.3: Mar 1 2001</h3> 2300<ul> 2301 <li>small change in XPath for XSLT</li> 2302 <li>documentation cleanups</li> 2303 <li>fix in validation by Gary Pennington</li> 2304 <li>serious parsing performances improvements</li> 2305</ul> 2306 2307<h3>2.3.2: Feb 24 2001</h3> 2308<ul> 2309 <li>chasing XPath bugs, found a bunch, completed some TODO</li> 2310 <li>fixed a Dtd parsing bug</li> 2311 <li>fixed a bug in xmlNodeGetContent</li> 2312 <li>ID/IDREF support partly rewritten by Gary Pennington</li> 2313</ul> 2314 2315<h3>2.3.1: Feb 15 2001</h3> 2316<ul> 2317 <li>some XPath and HTML bug fixes for XSLT</li> 2318 <li>small extension of the hash table interfaces for DOM gdome2 2319 implementation</li> 2320 <li>A few bug fixes</li> 2321</ul> 2322 2323<h3>2.3.0: Feb 8 2001 (2.2.12 was on 25 Jan but I didn't kept track)</h3> 2324<ul> 2325 <li>Lots of XPath bug fixes</li> 2326 <li>Add a mode with Dtd lookup but without validation error reporting for 2327 XSLT</li> 2328 <li>Add support for text node without escaping (XSLT)</li> 2329 <li>bug fixes for xmlCheckFilename</li> 2330 <li>validation code bug fixes from Gary Pennington</li> 2331 <li>Patch from Paul D. Smith correcting URI path normalization</li> 2332 <li>Patch to allow simultaneous install of libxml-devel and 2333 libxml2-devel</li> 2334 <li>the example Makefile is now fixed</li> 2335 <li>added HTML to the RPM packages</li> 2336 <li>tree copying bugfixes</li> 2337 <li>updates to Windows makefiles</li> 2338 <li>optimization patch from Bjorn Reese</li> 2339</ul> 2340 2341<h3>2.2.11: Jan 4 2001</h3> 2342<ul> 2343 <li>bunch of bug fixes (memory I/O, xpath, ftp/http, ...)</li> 2344 <li>added htmlHandleOmittedElem()</li> 2345 <li>Applied Bjorn Reese's IPV6 first patch</li> 2346 <li>Applied Paul D. Smith patches for validation of XInclude results</li> 2347 <li>added XPointer xmlns() new scheme support</li> 2348</ul> 2349 2350<h3>2.2.10: Nov 25 2000</h3> 2351<ul> 2352 <li>Fix the Windows problems of 2.2.8</li> 2353 <li>integrate OpenVMS patches</li> 2354 <li>better handling of some nasty HTML input</li> 2355 <li>Improved the XPointer implementation</li> 2356 <li>integrate a number of provided patches</li> 2357</ul> 2358 2359<h3>2.2.9: Nov 25 2000</h3> 2360<ul> 2361 <li>erroneous release :-(</li> 2362</ul> 2363 2364<h3>2.2.8: Nov 13 2000</h3> 2365<ul> 2366 <li>First version of <a href="http://www.w3.org/TR/xinclude">XInclude</a> 2367 support</li> 2368 <li>Patch in conditional section handling</li> 2369 <li>updated MS compiler project</li> 2370 <li>fixed some XPath problems</li> 2371 <li>added an URI escaping function</li> 2372 <li>some other bug fixes</li> 2373</ul> 2374 2375<h3>2.2.7: Oct 31 2000</h3> 2376<ul> 2377 <li>added message redirection</li> 2378 <li>XPath improvements (thanks TOM !)</li> 2379 <li>xmlIOParseDTD() added</li> 2380 <li>various small fixes in the HTML, URI, HTTP and XPointer support</li> 2381 <li>some cleanup of the Makefile, autoconf and the distribution content</li> 2382</ul> 2383 2384<h3>2.2.6: Oct 25 2000:</h3> 2385<ul> 2386 <li>Added an hash table module, migrated a number of internal structure to 2387 those</li> 2388 <li>Fixed a posteriori validation problems</li> 2389 <li>HTTP module cleanups</li> 2390 <li>HTML parser improvements (tag errors, script/style handling, attribute 2391 normalization)</li> 2392 <li>coalescing of adjacent text nodes</li> 2393 <li>couple of XPath bug fixes, exported the internal API</li> 2394</ul> 2395 2396<h3>2.2.5: Oct 15 2000:</h3> 2397<ul> 2398 <li>XPointer implementation and testsuite</li> 2399 <li>Lot of XPath fixes, added variable and functions registration, more 2400 tests</li> 2401 <li>Portability fixes, lots of enhancements toward an easy Windows build 2402 and release</li> 2403 <li>Late validation fixes</li> 2404 <li>Integrated a lot of contributed patches</li> 2405 <li>added memory management docs</li> 2406 <li>a performance problem when using large buffer seems fixed</li> 2407</ul> 2408 2409<h3>2.2.4: Oct 1 2000:</h3> 2410<ul> 2411 <li>main XPath problem fixed</li> 2412 <li>Integrated portability patches for Windows</li> 2413 <li>Serious bug fixes on the URI and HTML code</li> 2414</ul> 2415 2416<h3>2.2.3: Sep 17 2000</h3> 2417<ul> 2418 <li>bug fixes</li> 2419 <li>cleanup of entity handling code</li> 2420 <li>overall review of all loops in the parsers, all sprintf usage has been 2421 checked too</li> 2422 <li>Far better handling of larges Dtd. Validating against DocBook XML Dtd 2423 works smoothly now.</li> 2424</ul> 2425 2426<h3>1.8.10: Sep 6 2000</h3> 2427<ul> 2428 <li>bug fix release for some Gnome projects</li> 2429</ul> 2430 2431<h3>2.2.2: August 12 2000</h3> 2432<ul> 2433 <li>mostly bug fixes</li> 2434 <li>started adding routines to access xml parser context options</li> 2435</ul> 2436 2437<h3>2.2.1: July 21 2000</h3> 2438<ul> 2439 <li>a purely bug fixes release</li> 2440 <li>fixed an encoding support problem when parsing from a memory block</li> 2441 <li>fixed a DOCTYPE parsing problem</li> 2442 <li>removed a bug in the function allowing to override the memory 2443 allocation routines</li> 2444</ul> 2445 2446<h3>2.2.0: July 14 2000</h3> 2447<ul> 2448 <li>applied a lot of portability fixes</li> 2449 <li>better encoding support/cleanup and saving (content is now always 2450 encoded in UTF-8)</li> 2451 <li>the HTML parser now correctly handles encodings</li> 2452 <li>added xmlHasProp()</li> 2453 <li>fixed a serious problem with &#38;</li> 2454 <li>propagated the fix to FTP client</li> 2455 <li>cleanup, bugfixes, etc ...</li> 2456 <li>Added a page about <a href="encoding.html">libxml Internationalization 2457 support</a></li> 2458</ul> 2459 2460<h3>1.8.9: July 9 2000</h3> 2461<ul> 2462 <li>fixed the spec the RPMs should be better</li> 2463 <li>fixed a serious bug in the FTP implementation, released 1.8.9 to solve 2464 rpmfind users problem</li> 2465</ul> 2466 2467<h3>2.1.1: July 1 2000</h3> 2468<ul> 2469 <li>fixes a couple of bugs in the 2.1.0 packaging</li> 2470 <li>improvements on the HTML parser</li> 2471</ul> 2472 2473<h3>2.1.0 and 1.8.8: June 29 2000</h3> 2474<ul> 2475 <li>1.8.8 is mostly a commodity package for upgrading to libxml2 according 2476 to <a href="upgrade.html">new instructions</a>. It fixes a nasty problem 2477 about &#38; charref parsing</li> 2478 <li>2.1.0 also ease the upgrade from libxml v1 to the recent version. it 2479 also contains numerous fixes and enhancements: 2480 <ul> 2481 <li>added xmlStopParser() to stop parsing</li> 2482 <li>improved a lot parsing speed when there is large CDATA blocs</li> 2483 <li>includes XPath patches provided by Picdar Technology</li> 2484 <li>tried to fix as much as possible DTD validation and namespace 2485 related problems</li> 2486 <li>output to a given encoding has been added/tested</li> 2487 <li>lot of various fixes</li> 2488 </ul> 2489 </li> 2490</ul> 2491 2492<h3>2.0.0: Apr 12 2000</h3> 2493<ul> 2494 <li>First public release of libxml2. If you are using libxml, it's a good 2495 idea to check the 1.x to 2.x upgrade instructions. NOTE: while initially 2496 scheduled for Apr 3 the release occurred only on Apr 12 due to massive 2497 workload.</li> 2498 <li>The include are now located under $prefix/include/libxml (instead of 2499 $prefix/include/gnome-xml), they also are referenced by 2500 <pre>#include <libxml/xxx.h></pre> 2501 <p>instead of</p> 2502 <pre>#include "xxx.h"</pre> 2503 </li> 2504 <li>a new URI module for parsing URIs and following strictly RFC 2396</li> 2505 <li>the memory allocation routines used by libxml can now be overloaded 2506 dynamically by using xmlMemSetup()</li> 2507 <li>The previously CVS only tool tester has been renamed 2508 <strong>xmllint</strong> and is now installed as part of the libxml2 2509 package</li> 2510 <li>The I/O interface has been revamped. There is now ways to plug in 2511 specific I/O modules, either at the URI scheme detection level using 2512 xmlRegisterInputCallbacks() or by passing I/O functions when creating a 2513 parser context using xmlCreateIOParserCtxt()</li> 2514 <li>there is a C preprocessor macro LIBXML_VERSION providing the version 2515 number of the libxml module in use</li> 2516 <li>a number of optional features of libxml can now be excluded at 2517 configure time (FTP/HTTP/HTML/XPath/Debug)</li> 2518</ul> 2519 2520<h3>2.0.0beta: Mar 14 2000</h3> 2521<ul> 2522 <li>This is a first Beta release of libxml version 2</li> 2523 <li>It's available only from<a href="ftp://xmlsoft.org/libxml2/">xmlsoft.org 2524 FTP</a>, it's packaged as libxml2-2.0.0beta and available as tar and 2525 RPMs</li> 2526 <li>This version is now the head in the Gnome CVS base, the old one is 2527 available under the tag LIB_XML_1_X</li> 2528 <li>This includes a very large set of changes. From a programmatic point 2529 of view applications should not have to be modified too much, check the 2530 <a href="upgrade.html">upgrade page</a></li> 2531 <li>Some interfaces may changes (especially a bit about encoding).</li> 2532 <li>the updates includes: 2533 <ul> 2534 <li>fix I18N support. ISO-Latin-x/UTF-8/UTF-16 (nearly) seems correctly 2535 handled now</li> 2536 <li>Better handling of entities, especially well-formedness checking 2537 and proper PEref extensions in external subsets</li> 2538 <li>DTD conditional sections</li> 2539 <li>Validation now correctly handle entities content</li> 2540 <li><a href="http://rpmfind.net/tools/gdome/messages/0039.html">change 2541 structures to accommodate DOM</a></li> 2542 </ul> 2543 </li> 2544 <li>Serious progress were made toward compliance, <a 2545 href="conf/result.html">here are the result of the test</a> against the 2546 OASIS testsuite (except the Japanese tests since I don't support that 2547 encoding yet). This URL is rebuilt every couple of hours using the CVS 2548 head version.</li> 2549</ul> 2550 2551<h3>1.8.7: Mar 6 2000</h3> 2552<ul> 2553 <li>This is a bug fix release:</li> 2554 <li>It is possible to disable the ignorable blanks heuristic used by 2555 libxml-1.x, a new function xmlKeepBlanksDefault(0) will allow this. Note 2556 that for adherence to XML spec, this behaviour will be disabled by 2557 default in 2.x . The same function will allow to keep compatibility for 2558 old code.</li> 2559 <li>Blanks in <a> </a> constructs are not ignored anymore, 2560 avoiding heuristic is really the Right Way :-\</li> 2561 <li>The unchecked use of snprintf which was breaking libxml-1.8.6 2562 compilation on some platforms has been fixed</li> 2563 <li>nanoftp.c nanohttp.c: Fixed '#' and '?' stripping when processing 2564 URIs</li> 2565</ul> 2566 2567<h3>1.8.6: Jan 31 2000</h3> 2568<ul> 2569 <li>added a nanoFTP transport module, debugged until the new version of <a 2570 href="http://rpmfind.net/linux/rpm2html/rpmfind.html">rpmfind</a> can use 2571 it without troubles</li> 2572</ul> 2573 2574<h3>1.8.5: Jan 21 2000</h3> 2575<ul> 2576 <li>adding APIs to parse a well balanced chunk of XML (production <a 2577 href="http://www.w3.org/TR/REC-xml#NT-content">[43] content</a> of the 2578 XML spec)</li> 2579 <li>fixed a hideous bug in xmlGetProp pointed by Rune.Djurhuus@fast.no</li> 2580 <li>Jody Goldberg <jgoldberg@home.com> provided another patch trying 2581 to solve the zlib checks problems</li> 2582 <li>The current state in gnome CVS base is expected to ship as 1.8.5 with 2583 gnumeric soon</li> 2584</ul> 2585 2586<h3>1.8.4: Jan 13 2000</h3> 2587<ul> 2588 <li>bug fixes, reintroduced xmlNewGlobalNs(), fixed xmlNewNs()</li> 2589 <li>all exit() call should have been removed from libxml</li> 2590 <li>fixed a problem with INCLUDE_WINSOCK on WIN32 platform</li> 2591 <li>added newDocFragment()</li> 2592</ul> 2593 2594<h3>1.8.3: Jan 5 2000</h3> 2595<ul> 2596 <li>a Push interface for the XML and HTML parsers</li> 2597 <li>a shell-like interface to the document tree (try tester --shell :-)</li> 2598 <li>lots of bug fixes and improvement added over XMas holidays</li> 2599 <li>fixed the DTD parsing code to work with the xhtml DTD</li> 2600 <li>added xmlRemoveProp(), xmlRemoveID() and xmlRemoveRef()</li> 2601 <li>Fixed bugs in xmlNewNs()</li> 2602 <li>External entity loading code has been revamped, now it uses 2603 xmlLoadExternalEntity(), some fix on entities processing were added</li> 2604 <li>cleaned up WIN32 includes of socket stuff</li> 2605</ul> 2606 2607<h3>1.8.2: Dec 21 1999</h3> 2608<ul> 2609 <li>I got another problem with includes and C++, I hope this issue is fixed 2610 for good this time</li> 2611 <li>Added a few tree modification functions: xmlReplaceNode, 2612 xmlAddPrevSibling, xmlAddNextSibling, xmlNodeSetName and 2613 xmlDocSetRootElement</li> 2614 <li>Tried to improve the HTML output with help from <a 2615 href="mailto:clahey@umich.edu">Chris Lahey</a></li> 2616</ul> 2617 2618<h3>1.8.1: Dec 18 1999</h3> 2619<ul> 2620 <li>various patches to avoid troubles when using libxml with C++ compilers 2621 the "namespace" keyword and C escaping in include files</li> 2622 <li>a problem in one of the core macros IS_CHAR was corrected</li> 2623 <li>fixed a bug introduced in 1.8.0 breaking default namespace processing, 2624 and more specifically the Dia application</li> 2625 <li>fixed a posteriori validation (validation after parsing, or by using a 2626 Dtd not specified in the original document)</li> 2627 <li>fixed a bug in</li> 2628</ul> 2629 2630<h3>1.8.0: Dec 12 1999</h3> 2631<ul> 2632 <li>cleanup, especially memory wise</li> 2633 <li>the parser should be more reliable, especially the HTML one, it should 2634 not crash, whatever the input !</li> 2635 <li>Integrated various patches, especially a speedup improvement for large 2636 dataset from <a href="mailto:cnygard@bellatlantic.net">Carl Nygard</a>, 2637 configure with --with-buffers to enable them.</li> 2638 <li>attribute normalization, oops should have been added long ago !</li> 2639 <li>attributes defaulted from DTDs should be available, xmlSetProp() now 2640 does entities escaping by default.</li> 2641</ul> 2642 2643<h3>1.7.4: Oct 25 1999</h3> 2644<ul> 2645 <li>Lots of HTML improvement</li> 2646 <li>Fixed some errors when saving both XML and HTML</li> 2647 <li>More examples, the regression tests should now look clean</li> 2648 <li>Fixed a bug with contiguous charref</li> 2649</ul> 2650 2651<h3>1.7.3: Sep 29 1999</h3> 2652<ul> 2653 <li>portability problems fixed</li> 2654 <li>snprintf was used unconditionally, leading to link problems on system 2655 were it's not available, fixed</li> 2656</ul> 2657 2658<h3>1.7.1: Sep 24 1999</h3> 2659<ul> 2660 <li>The basic type for strings manipulated by libxml has been renamed in 2661 1.7.1 from <strong>CHAR</strong> to <strong>xmlChar</strong>. The reason 2662 is that CHAR was conflicting with a predefined type on Windows. However 2663 on non WIN32 environment, compatibility is provided by the way of a 2664 <strong>#define </strong>.</li> 2665 <li>Changed another error : the use of a structure field called errno, and 2666 leading to troubles on platforms where it's a macro</li> 2667</ul> 2668 2669<h3>1.7.0: Sep 23 1999</h3> 2670<ul> 2671 <li>Added the ability to fetch remote DTD or parsed entities, see the <a 2672 href="html/libxml-nanohttp.html">nanohttp</a> module.</li> 2673 <li>Added an errno to report errors by another mean than a simple printf 2674 like callback</li> 2675 <li>Finished ID/IDREF support and checking when validation</li> 2676 <li>Serious memory leaks fixed (there is now a <a 2677 href="html/libxml-xmlmemory.html">memory wrapper</a> module)</li> 2678 <li>Improvement of <a href="http://www.w3.org/TR/xpath">XPath</a> 2679 implementation</li> 2680 <li>Added an HTML parser front-end</li> 2681</ul> 2682 2683<h2><a name="XML">XML</a></h2> 2684 2685<p><a href="http://www.w3.org/TR/REC-xml">XML is a standard</a> for 2686markup-based structured documents. Here is <a name="example">an example XML 2687document</a>:</p> 2688<pre><?xml version="1.0"?> 2689<EXAMPLE prop1="gnome is great" prop2="&amp; linux too"> 2690 <head> 2691 <title>Welcome to Gnome</title> 2692 </head> 2693 <chapter> 2694 <title>The Linux adventure</title> 2695 <p>bla bla bla ...</p> 2696 <image href="linus.gif"/> 2697 <p>...</p> 2698 </chapter> 2699</EXAMPLE></pre> 2700 2701<p>The first line specifies that it is an XML document and gives useful 2702information about its encoding. Then the rest of the document is a text 2703format whose structure is specified by tags between brackets. <strong>Each 2704tag opened has to be closed</strong>. XML is pedantic about this. However, if 2705a tag is empty (no content), a single tag can serve as both the opening and 2706closing tag if it ends with <code>/></code> rather than with 2707<code>></code>. Note that, for example, the image tag has no content (just 2708an attribute) and is closed by ending the tag with <code>/></code>.</p> 2709 2710<p>XML can be applied successfully to a wide range of tasks, ranging from 2711long term structured document maintenance (where it follows the steps of 2712SGML) to simple data encoding mechanisms like configuration file formatting 2713(glade), spreadsheets (gnumeric), or even shorter lived documents such as 2714WebDAV where it is used to encode remote calls between a client and a 2715server.</p> 2716 2717<h2><a name="XSLT">XSLT</a></h2> 2718 2719<p>Check <a href="http://xmlsoft.org/XSLT">the separate libxslt page</a></p> 2720 2721<p><a href="http://www.w3.org/TR/xslt">XSL Transformations</a>, is a 2722language for transforming XML documents into other XML documents (or 2723HTML/textual output).</p> 2724 2725<p>A separate library called libxslt is available implementing XSLT-1.0 for 2726libxml2. This module "libxslt" too can be found in the Gnome SVN base.</p> 2727 2728<p>You can check the progresses on the libxslt <a 2729href="http://xmlsoft.org/XSLT/ChangeLog.html">Changelog</a>.</p> 2730 2731<h2><a name="Python">Python and bindings</a></h2> 2732 2733<p>There are a number of language bindings and wrappers available for 2734libxml2, the list below is not exhaustive. Please contact the <a 2735href="http://mail.gnome.org/mailman/listinfo/xml-bindings">xml-bindings@gnome.org</a> 2736(<a href="http://mail.gnome.org/archives/xml-bindings/">archives</a>) in 2737order to get updates to this list or to discuss the specific topic of libxml2 2738or libxslt wrappers or bindings:</p> 2739<ul> 2740 <li><a href="http://libxmlplusplus.sourceforge.net/">Libxml++</a> seems the 2741 most up-to-date C++ bindings for libxml2, check the <a 2742 href="http://libxmlplusplus.sourceforge.net/reference/html/hierarchy.html">documentation</a> 2743 and the <a 2744 href="http://cvs.sourceforge.net/cgi-bin/viewcvs.cgi/libxmlplusplus/libxml%2b%2b/examples/">examples</a>.</li> 2745 <li>There is another <a href="http://libgdome-cpp.berlios.de/">C++ wrapper 2746 based on the gdome2 bindings</a> maintained by Tobias Peters.</li> 2747 <li>and a third C++ wrapper by Peter Jones <pjones@pmade.org> 2748 <p>Website: <a 2749 href="http://pmade.org/pjones/software/xmlwrapp/">http://pmade.org/pjones/software/xmlwrapp/</a></p> 2750 </li> 2751 <li>XML::LibXML <a href="http://cpan.uwinnipeg.ca/dist/XML-LibXML">Perl 2752 bindings</a> are available on CPAN, as well as XML::LibXSLT 2753 <a href="http://cpan.uwinnipeg.ca/dist/XML-LibXSLT">Perl libxslt 2754 bindings</a>.</li> 2755 <li>If you're interested into scripting XML processing, have a look at <a 2756 href="http://xsh.sourceforge.net/">XSH</a> an XML editing shell based on 2757 Libxml2 Perl bindings.</li> 2758 <li><a href="mailto:dkuhlman@cutter.rexx.com">Dave Kuhlman</a> provides an 2759 earlier version of the libxml/libxslt <a 2760 href="http://www.rexx.com/~dkuhlman">wrappers for Python</a>.</li> 2761 <li>Gopal.V and Peter Minten develop <a 2762 href="http://savannah.gnu.org/projects/libxmlsharp">libxml#</a>, a set of 2763 C# libxml2 bindings.</li> 2764 <li>Petr Kozelka provides <a 2765 href="http://sourceforge.net/projects/libxml2-pas">Pascal units to glue 2766 libxml2</a> with Kylix, Delphi and other Pascal compilers.</li> 2767 <li>Uwe Fechner also provides <a 2768 href="http://sourceforge.net/projects/idom2-pas/">idom2</a>, a DOM2 2769 implementation for Kylix2/D5/D6 from Borland.</li> 2770 <li>There is <a href="http://libxml.rubyforge.org/">bindings for Ruby</a> 2771 and libxml2 bindings are also available in Ruby through the <a 2772 href="http://libgdome-ruby.berlios.de/">libgdome-ruby</a> module 2773 maintained by Tobias Peters.</li> 2774 <li>Steve Ball and contributors maintains <a 2775 href="http://tclxml.sourceforge.net/">libxml2 and libxslt bindings for 2776 Tcl</a>.</li> 2777 <li>libxml2 and libxslt are the default XML libraries for PHP5.</li> 2778 <li><a href="http://savannah.gnu.org/projects/classpathx/">LibxmlJ</a> is 2779 an effort to create a 100% JAXP-compatible Java wrapper for libxml2 and 2780 libxslt as part of GNU ClasspathX project.</li> 2781 <li>Patrick McPhee provides Rexx bindings fof libxml2 and libxslt, look for 2782 <a href="http://www.interlog.com/~ptjm/software.html">RexxXML</a>.</li> 2783 <li><a 2784 href="http://www.satimage.fr/software/en/xml_suite.html">Satimage</a> 2785 provides <a 2786 href="http://www.satimage.fr/software/en/downloads_osaxen.html">XMLLib 2787 osax</a>. This is an osax for Mac OS X with a set of commands to 2788 implement in AppleScript the XML DOM, XPATH and XSLT. Also includes 2789 commands for Property-lists (Apple's fast lookup table XML format.)</li> 2790 <li>Francesco Montorsi developped <a 2791 href="https://sourceforge.net/project/showfiles.php?group_id=51305&package_id=45182">wxXml2</a> 2792 wrappers that interface libxml2, allowing wxWidgets applications to 2793 load/save/edit XML instances.</li> 2794</ul> 2795 2796<p>The distribution includes a set of Python bindings, which are guaranteed 2797to be maintained as part of the library in the future, though the Python 2798interface have not yet reached the completeness of the C API.</p> 2799 2800<p>Note that some of the Python purist dislike the default set of Python 2801bindings, rather than complaining I suggest they have a look at <a 2802href="http://codespeak.net/lxml/">lxml the more pythonic bindings for libxml2 2803and libxslt</a> and <a 2804href="http://codespeak.net/mailman/listinfo/lxml-dev">help Martijn 2805Faassen</a> complete those.</p> 2806 2807<p><a href="mailto:stephane.bidoul@softwareag.com">St�phane Bidoul</a> 2808maintains <a href="http://users.skynet.be/sbi/libxml-python/">a Windows port 2809of the Python bindings</a>.</p> 2810 2811<p>Note to people interested in building bindings, the API is formalized as 2812<a href="libxml2-api.xml">an XML API description file</a> which allows to 2813automate a large part of the Python bindings, this includes function 2814descriptions, enums, structures, typedefs, etc... The Python script used to 2815build the bindings is python/generator.py in the source distribution.</p> 2816 2817<p>To install the Python bindings there are 2 options:</p> 2818<ul> 2819 <li>If you use an RPM based distribution, simply install the <a 2820 href="http://rpmfind.net/linux/rpm2html/search.php?query=libxml2-python">libxml2-python 2821 RPM</a> (and if needed the <a 2822 href="http://rpmfind.net/linux/rpm2html/search.php?query=libxslt-python">libxslt-python 2823 RPM</a>).</li> 2824 <li>Otherwise use the <a href="ftp://xmlsoft.org/libxml2/python/">libxml2-python 2825 module distribution</a> corresponding to your installed version of 2826 libxml2 and libxslt. Note that to install it you will need both libxml2 2827 and libxslt installed and run "python setup.py build install" in the 2828 module tree.</li> 2829</ul> 2830 2831<p>The distribution includes a set of examples and regression tests for the 2832python bindings in the <code>python/tests</code> directory. Here are some 2833excerpts from those tests:</p> 2834 2835<h3>tst.py:</h3> 2836 2837<p>This is a basic test of the file interface and DOM navigation:</p> 2838<pre>import libxml2, sys 2839 2840doc = libxml2.parseFile("tst.xml") 2841if doc.name != "tst.xml": 2842 print "doc.name failed" 2843 sys.exit(1) 2844root = doc.children 2845if root.name != "doc": 2846 print "root.name failed" 2847 sys.exit(1) 2848child = root.children 2849if child.name != "foo": 2850 print "child.name failed" 2851 sys.exit(1) 2852doc.freeDoc()</pre> 2853 2854<p>The Python module is called libxml2; parseFile is the equivalent of 2855xmlParseFile (most of the bindings are automatically generated, and the xml 2856prefix is removed and the casing convention are kept). All node seen at the 2857binding level share the same subset of accessors:</p> 2858<ul> 2859 <li><code>name</code> : returns the node name</li> 2860 <li><code>type</code> : returns a string indicating the node type</li> 2861 <li><code>content</code> : returns the content of the node, it is based on 2862 xmlNodeGetContent() and hence is recursive.</li> 2863 <li><code>parent</code> , <code>children</code>, <code>last</code>, 2864 <code>next</code>, <code>prev</code>, <code>doc</code>, 2865 <code>properties</code>: pointing to the associated element in the tree, 2866 those may return None in case no such link exists.</li> 2867</ul> 2868 2869<p>Also note the need to explicitly deallocate documents with freeDoc() . 2870Reference counting for libxml2 trees would need quite a lot of work to 2871function properly, and rather than risk memory leaks if not implemented 2872correctly it sounds safer to have an explicit function to free a tree. The 2873wrapper python objects like doc, root or child are them automatically garbage 2874collected.</p> 2875 2876<h3>validate.py:</h3> 2877 2878<p>This test check the validation interfaces and redirection of error 2879messages:</p> 2880<pre>import libxml2 2881 2882#deactivate error messages from the validation 2883def noerr(ctx, str): 2884 pass 2885 2886libxml2.registerErrorHandler(noerr, None) 2887 2888ctxt = libxml2.createFileParserCtxt("invalid.xml") 2889ctxt.validate(1) 2890ctxt.parseDocument() 2891doc = ctxt.doc() 2892valid = ctxt.isValid() 2893doc.freeDoc() 2894if valid != 0: 2895 print "validity check failed"</pre> 2896 2897<p>The first thing to notice is the call to registerErrorHandler(), it 2898defines a new error handler global to the library. It is used to avoid seeing 2899the error messages when trying to validate the invalid document.</p> 2900 2901<p>The main interest of that test is the creation of a parser context with 2902createFileParserCtxt() and how the behaviour can be changed before calling 2903parseDocument() . Similarly the information resulting from the parsing phase 2904is also available using context methods.</p> 2905 2906<p>Contexts like nodes are defined as class and the libxml2 wrappers maps the 2907C function interfaces in terms of objects method as much as possible. The 2908best to get a complete view of what methods are supported is to look at the 2909libxml2.py module containing all the wrappers.</p> 2910 2911<h3>push.py:</h3> 2912 2913<p>This test show how to activate the push parser interface:</p> 2914<pre>import libxml2 2915 2916ctxt = libxml2.createPushParser(None, "<foo", 4, "test.xml") 2917ctxt.parseChunk("/>", 2, 1) 2918doc = ctxt.doc() 2919 2920doc.freeDoc()</pre> 2921 2922<p>The context is created with a special call based on the 2923xmlCreatePushParser() from the C library. The first argument is an optional 2924SAX callback object, then the initial set of data, the length and the name of 2925the resource in case URI-References need to be computed by the parser.</p> 2926 2927<p>Then the data are pushed using the parseChunk() method, the last call 2928setting the third argument terminate to 1.</p> 2929 2930<h3>pushSAX.py:</h3> 2931 2932<p>this test show the use of the event based parsing interfaces. In this case 2933the parser does not build a document, but provides callback information as 2934the parser makes progresses analyzing the data being provided:</p> 2935<pre>import libxml2 2936log = "" 2937 2938class callback: 2939 def startDocument(self): 2940 global log 2941 log = log + "startDocument:" 2942 2943 def endDocument(self): 2944 global log 2945 log = log + "endDocument:" 2946 2947 def startElement(self, tag, attrs): 2948 global log 2949 log = log + "startElement %s %s:" % (tag, attrs) 2950 2951 def endElement(self, tag): 2952 global log 2953 log = log + "endElement %s:" % (tag) 2954 2955 def characters(self, data): 2956 global log 2957 log = log + "characters: %s:" % (data) 2958 2959 def warning(self, msg): 2960 global log 2961 log = log + "warning: %s:" % (msg) 2962 2963 def error(self, msg): 2964 global log 2965 log = log + "error: %s:" % (msg) 2966 2967 def fatalError(self, msg): 2968 global log 2969 log = log + "fatalError: %s:" % (msg) 2970 2971handler = callback() 2972 2973ctxt = libxml2.createPushParser(handler, "<foo", 4, "test.xml") 2974chunk = " url='tst'>b" 2975ctxt.parseChunk(chunk, len(chunk), 0) 2976chunk = "ar</foo>" 2977ctxt.parseChunk(chunk, len(chunk), 1) 2978 2979reference = "startDocument:startElement foo {'url': 'tst'}:" + \ 2980 "characters: bar:endElement foo:endDocument:" 2981if log != reference: 2982 print "Error got: %s" % log 2983 print "Expected: %s" % reference</pre> 2984 2985<p>The key object in that test is the handler, it provides a number of entry 2986points which can be called by the parser as it makes progresses to indicate 2987the information set obtained. The full set of callback is larger than what 2988the callback class in that specific example implements (see the SAX 2989definition for a complete list). The wrapper will only call those supplied by 2990the object when activated. The startElement receives the names of the element 2991and a dictionary containing the attributes carried by this element.</p> 2992 2993<p>Also note that the reference string generated from the callback shows a 2994single character call even though the string "bar" is passed to the parser 2995from 2 different call to parseChunk()</p> 2996 2997<h3>xpath.py:</h3> 2998 2999<p>This is a basic test of XPath wrappers support</p> 3000<pre>import libxml2 3001 3002doc = libxml2.parseFile("tst.xml") 3003ctxt = doc.xpathNewContext() 3004res = ctxt.xpathEval("//*") 3005if len(res) != 2: 3006 print "xpath query: wrong node set size" 3007 sys.exit(1) 3008if res[0].name != "doc" or res[1].name != "foo": 3009 print "xpath query: wrong node set value" 3010 sys.exit(1) 3011doc.freeDoc() 3012ctxt.xpathFreeContext()</pre> 3013 3014<p>This test parses a file, then create an XPath context to evaluate XPath 3015expression on it. The xpathEval() method execute an XPath query and returns 3016the result mapped in a Python way. String and numbers are natively converted, 3017and node sets are returned as a tuple of libxml2 Python nodes wrappers. Like 3018the document, the XPath context need to be freed explicitly, also not that 3019the result of the XPath query may point back to the document tree and hence 3020the document must be freed after the result of the query is used.</p> 3021 3022<h3>xpathext.py:</h3> 3023 3024<p>This test shows how to extend the XPath engine with functions written in 3025python:</p> 3026<pre>import libxml2 3027 3028def foo(ctx, x): 3029 return x + 1 3030 3031doc = libxml2.parseFile("tst.xml") 3032ctxt = doc.xpathNewContext() 3033libxml2.registerXPathFunction(ctxt._o, "foo", None, foo) 3034res = ctxt.xpathEval("foo(1)") 3035if res != 2: 3036 print "xpath extension failure" 3037doc.freeDoc() 3038ctxt.xpathFreeContext()</pre> 3039 3040<p>Note how the extension function is registered with the context (but that 3041part is not yet finalized, this may change slightly in the future).</p> 3042 3043<h3>tstxpath.py:</h3> 3044 3045<p>This test is similar to the previous one but shows how the extension 3046function can access the XPath evaluation context:</p> 3047<pre>def foo(ctx, x): 3048 global called 3049 3050 # 3051 # test that access to the XPath evaluation contexts 3052 # 3053 pctxt = libxml2.xpathParserContext(_obj=ctx) 3054 ctxt = pctxt.context() 3055 called = ctxt.function() 3056 return x + 1</pre> 3057 3058<p>All the interfaces around the XPath parser(or rather evaluation) context 3059are not finalized, but it should be sufficient to do contextual work at the 3060evaluation point.</p> 3061 3062<h3>Memory debugging:</h3> 3063 3064<p>last but not least, all tests starts with the following prologue:</p> 3065<pre>#memory debug specific 3066libxml2.debugMemory(1)</pre> 3067 3068<p>and ends with the following epilogue:</p> 3069<pre>#memory debug specific 3070libxml2.cleanupParser() 3071if libxml2.debugMemory(1) == 0: 3072 print "OK" 3073else: 3074 print "Memory leak %d bytes" % (libxml2.debugMemory(1)) 3075 libxml2.dumpMemory()</pre> 3076 3077<p>Those activate the memory debugging interface of libxml2 where all 3078allocated block in the library are tracked. The prologue then cleans up the 3079library state and checks that all allocated memory has been freed. If not it 3080calls dumpMemory() which saves that list in a <code>.memdump</code> file.</p> 3081 3082<h2><a name="architecture">libxml2 architecture</a></h2> 3083 3084<p>Libxml2 is made of multiple components; some of them are optional, and 3085most of the block interfaces are public. The main components are:</p> 3086<ul> 3087 <li>an Input/Output layer</li> 3088 <li>FTP and HTTP client layers (optional)</li> 3089 <li>an Internationalization layer managing the encodings support</li> 3090 <li>a URI module</li> 3091 <li>the XML parser and its basic SAX interface</li> 3092 <li>an HTML parser using the same SAX interface (optional)</li> 3093 <li>a SAX tree module to build an in-memory DOM representation</li> 3094 <li>a tree module to manipulate the DOM representation</li> 3095 <li>a validation module using the DOM representation (optional)</li> 3096 <li>an XPath module for global lookup in a DOM representation 3097 (optional)</li> 3098 <li>a debug module (optional)</li> 3099</ul> 3100 3101<p>Graphically this gives the following:</p> 3102 3103<p><img src="libxml.gif" alt="a graphical view of the various"></p> 3104 3105<p></p> 3106 3107<h2><a name="tree">The tree output</a></h2> 3108 3109<p>The parser returns a tree built during the document analysis. The value 3110returned is an <strong>xmlDocPtr</strong> (i.e., a pointer to an 3111<strong>xmlDoc</strong> structure). This structure contains information such 3112as the file name, the document type, and a <strong>children</strong> pointer 3113which is the root of the document (or more exactly the first child under the 3114root which is the document). The tree is made of <strong>xmlNode</strong>s, 3115chained in double-linked lists of siblings and with a children<->parent 3116relationship. An xmlNode can also carry properties (a chain of xmlAttr 3117structures). An attribute may have a value which is a list of TEXT or 3118ENTITY_REF nodes.</p> 3119 3120<p>Here is an example (erroneous with respect to the XML spec since there 3121should be only one ELEMENT under the root):</p> 3122 3123<p><img src="structure.gif" alt=" structure.gif "></p> 3124 3125<p>In the source package there is a small program (not installed by default) 3126called <strong>xmllint</strong> which parses XML files given as argument and 3127prints them back as parsed. This is useful for detecting errors both in XML 3128code and in the XML parser itself. It has an option <strong>--debug</strong> 3129which prints the actual in-memory structure of the document; here is the 3130result with the <a href="#example">example</a> given before:</p> 3131<pre>DOCUMENT 3132version=1.0 3133standalone=true 3134 ELEMENT EXAMPLE 3135 ATTRIBUTE prop1 3136 TEXT 3137 content=gnome is great 3138 ATTRIBUTE prop2 3139 ENTITY_REF 3140 TEXT 3141 content= linux too 3142 ELEMENT head 3143 ELEMENT title 3144 TEXT 3145 content=Welcome to Gnome 3146 ELEMENT chapter 3147 ELEMENT title 3148 TEXT 3149 content=The Linux adventure 3150 ELEMENT p 3151 TEXT 3152 content=bla bla bla ... 3153 ELEMENT image 3154 ATTRIBUTE href 3155 TEXT 3156 content=linus.gif 3157 ELEMENT p 3158 TEXT 3159 content=...</pre> 3160 3161<p>This should be useful for learning the internal representation model.</p> 3162 3163<h2><a name="interface">The SAX interface</a></h2> 3164 3165<p>Sometimes the DOM tree output is just too large to fit reasonably into 3166memory. In that case (and if you don't expect to save back the XML document 3167loaded using libxml), it's better to use the SAX interface of libxml. SAX is 3168a <strong>callback-based interface</strong> to the parser. Before parsing, 3169the application layer registers a customized set of callbacks which are 3170called by the library as it progresses through the XML input.</p> 3171 3172<p>To get more detailed step-by-step guidance on using the SAX interface of 3173libxml, see the <a 3174href="http://www.daa.com.au/~james/gnome/xml-sax/xml-sax.html">nice 3175documentation</a>.written by <a href="mailto:james@daa.com.au">James 3176Henstridge</a>.</p> 3177 3178<p>You can debug the SAX behaviour by using the <strong>testSAX</strong> 3179program located in the gnome-xml module (it's usually not shipped in the 3180binary packages of libxml, but you can find it in the tar source 3181distribution). Here is the sequence of callbacks that would be reported by 3182testSAX when parsing the example XML document shown earlier:</p> 3183<pre>SAX.setDocumentLocator() 3184SAX.startDocument() 3185SAX.getEntity(amp) 3186SAX.startElement(EXAMPLE, prop1='gnome is great', prop2='&amp; linux too') 3187SAX.characters( , 3) 3188SAX.startElement(head) 3189SAX.characters( , 4) 3190SAX.startElement(title) 3191SAX.characters(Welcome to Gnome, 16) 3192SAX.endElement(title) 3193SAX.characters( , 3) 3194SAX.endElement(head) 3195SAX.characters( , 3) 3196SAX.startElement(chapter) 3197SAX.characters( , 4) 3198SAX.startElement(title) 3199SAX.characters(The Linux adventure, 19) 3200SAX.endElement(title) 3201SAX.characters( , 4) 3202SAX.startElement(p) 3203SAX.characters(bla bla bla ..., 15) 3204SAX.endElement(p) 3205SAX.characters( , 4) 3206SAX.startElement(image, href='linus.gif') 3207SAX.endElement(image) 3208SAX.characters( , 4) 3209SAX.startElement(p) 3210SAX.characters(..., 3) 3211SAX.endElement(p) 3212SAX.characters( , 3) 3213SAX.endElement(chapter) 3214SAX.characters( , 1) 3215SAX.endElement(EXAMPLE) 3216SAX.endDocument()</pre> 3217 3218<p>Most of the other interfaces of libxml2 are based on the DOM tree-building 3219facility, so nearly everything up to the end of this document presupposes the 3220use of the standard DOM tree build. Note that the DOM tree itself is built by 3221a set of registered default callbacks, without internal specific 3222interface.</p> 3223 3224<h2><a name="Validation">Validation & DTDs</a></h2> 3225 3226<p>Table of Content:</p> 3227<ol> 3228 <li><a href="#General5">General overview</a></li> 3229 <li><a href="#definition">The definition</a></li> 3230 <li><a href="#Simple">Simple rules</a> 3231 <ol> 3232 <li><a href="#reference">How to reference a DTD from a document</a></li> 3233 <li><a href="#Declaring">Declaring elements</a></li> 3234 <li><a href="#Declaring1">Declaring attributes</a></li> 3235 </ol> 3236 </li> 3237 <li><a href="#Some">Some examples</a></li> 3238 <li><a href="#validate">How to validate</a></li> 3239 <li><a href="#Other">Other resources</a></li> 3240</ol> 3241 3242<h3><a name="General5">General overview</a></h3> 3243 3244<p>Well what is validation and what is a DTD ?</p> 3245 3246<p>DTD is the acronym for Document Type Definition. This is a description of 3247the content for a family of XML files. This is part of the XML 1.0 3248specification, and allows one to describe and verify that a given document 3249instance conforms to the set of rules detailing its structure and content.</p> 3250 3251<p>Validation is the process of checking a document against a DTD (more 3252generally against a set of construction rules).</p> 3253 3254<p>The validation process and building DTDs are the two most difficult parts 3255of the XML life cycle. Briefly a DTD defines all the possible elements to be 3256found within your document, what is the formal shape of your document tree 3257(by defining the allowed content of an element; either text, a regular 3258expression for the allowed list of children, or mixed content i.e. both text 3259and children). The DTD also defines the valid attributes for all elements and 3260the types of those attributes.</p> 3261 3262<h3><a name="definition1">The definition</a></h3> 3263 3264<p>The <a href="http://www.w3.org/TR/REC-xml">W3C XML Recommendation</a> (<a 3265href="http://www.xml.com/axml/axml.html">Tim Bray's annotated version of 3266Rev1</a>):</p> 3267<ul> 3268 <li><a href="http://www.w3.org/TR/REC-xml#elemdecls">Declaring 3269 elements</a></li> 3270 <li><a href="http://www.w3.org/TR/REC-xml#attdecls">Declaring 3271 attributes</a></li> 3272</ul> 3273 3274<p>(unfortunately) all this is inherited from the SGML world, the syntax is 3275ancient...</p> 3276 3277<h3><a name="Simple1">Simple rules</a></h3> 3278 3279<p>Writing DTDs can be done in many ways. The rules to build them if you need 3280something permanent or something which can evolve over time can be radically 3281different. Really complex DTDs like DocBook ones are flexible but quite 3282harder to design. I will just focus on DTDs for a formats with a fixed simple 3283structure. It is just a set of basic rules, and definitely not exhaustive nor 3284usable for complex DTD design.</p> 3285 3286<h4><a name="reference1">How to reference a DTD from a document</a>:</h4> 3287 3288<p>Assuming the top element of the document is <code>spec</code> and the dtd 3289is placed in the file <code>mydtd</code> in the subdirectory 3290<code>dtds</code> of the directory from where the document were loaded:</p> 3291 3292<p><code><!DOCTYPE spec SYSTEM "dtds/mydtd"></code></p> 3293 3294<p>Notes:</p> 3295<ul> 3296 <li>The system string is actually an URI-Reference (as defined in <a 3297 href="http://www.ietf.org/rfc/rfc2396.txt">RFC 2396</a>) so you can use a 3298 full URL string indicating the location of your DTD on the Web. This is a 3299 really good thing to do if you want others to validate your document.</li> 3300 <li>It is also possible to associate a <code>PUBLIC</code> identifier (a 3301 magic string) so that the DTD is looked up in catalogs on the client side 3302 without having to locate it on the web.</li> 3303 <li>A DTD contains a set of element and attribute declarations, but they 3304 don't define what the root of the document should be. This is explicitly 3305 told to the parser/validator as the first element of the 3306 <code>DOCTYPE</code> declaration.</li> 3307</ul> 3308 3309<h4><a name="Declaring2">Declaring elements</a>:</h4> 3310 3311<p>The following declares an element <code>spec</code>:</p> 3312 3313<p><code><!ELEMENT spec (front, body, back?)></code></p> 3314 3315<p>It also expresses that the spec element contains one <code>front</code>, 3316one <code>body</code> and one optional <code>back</code> children elements in 3317this order. The declaration of one element of the structure and its content 3318are done in a single declaration. Similarly the following declares 3319<code>div1</code> elements:</p> 3320 3321<p><code><!ELEMENT div1 (head, (p | list | note)*, div2?)></code></p> 3322 3323<p>which means div1 contains one <code>head</code> then a series of optional 3324<code>p</code>, <code>list</code>s and <code>note</code>s and then an 3325optional <code>div2</code>. And last but not least an element can contain 3326text:</p> 3327 3328<p><code><!ELEMENT b (#PCDATA)></code></p> 3329 3330<p><code>b</code> contains text or being of mixed content (text and elements 3331in no particular order):</p> 3332 3333<p><code><!ELEMENT p (#PCDATA|a|ul|b|i|em)*></code></p> 3334 3335<p><code>p </code>can contain text or <code>a</code>, <code>ul</code>, 3336<code>b</code>, <code>i </code>or <code>em</code> elements in no particular 3337order.</p> 3338 3339<h4><a name="Declaring1">Declaring attributes</a>:</h4> 3340 3341<p>Again the attributes declaration includes their content definition:</p> 3342 3343<p><code><!ATTLIST termdef name CDATA #IMPLIED></code></p> 3344 3345<p>means that the element <code>termdef</code> can have a <code>name</code> 3346attribute containing text (<code>CDATA</code>) and which is optional 3347(<code>#IMPLIED</code>). The attribute value can also be defined within a 3348set:</p> 3349 3350<p><code><!ATTLIST list type (bullets|ordered|glossary) 3351"ordered"></code></p> 3352 3353<p>means <code>list</code> element have a <code>type</code> attribute with 3 3354allowed values "bullets", "ordered" or "glossary" and which default to 3355"ordered" if the attribute is not explicitly specified.</p> 3356 3357<p>The content type of an attribute can be text (<code>CDATA</code>), 3358anchor/reference/references 3359(<code>ID</code>/<code>IDREF</code>/<code>IDREFS</code>), entity(ies) 3360(<code>ENTITY</code>/<code>ENTITIES</code>) or name(s) 3361(<code>NMTOKEN</code>/<code>NMTOKENS</code>). The following defines that a 3362<code>chapter</code> element can have an optional <code>id</code> attribute 3363of type <code>ID</code>, usable for reference from attribute of type 3364IDREF:</p> 3365 3366<p><code><!ATTLIST chapter id ID #IMPLIED></code></p> 3367 3368<p>The last value of an attribute definition can be <code>#REQUIRED 3369</code>meaning that the attribute has to be given, <code>#IMPLIED</code> 3370meaning that it is optional, or the default value (possibly prefixed by 3371<code>#FIXED</code> if it is the only allowed).</p> 3372 3373<p>Notes:</p> 3374<ul> 3375 <li>Usually the attributes pertaining to a given element are declared in a 3376 single expression, but it is just a convention adopted by a lot of DTD 3377 writers: 3378 <pre><!ATTLIST termdef 3379 id ID #REQUIRED 3380 name CDATA #IMPLIED></pre> 3381 <p>The previous construct defines both <code>id</code> and 3382 <code>name</code> attributes for the element <code>termdef</code>.</p> 3383 </li> 3384</ul> 3385 3386<h3><a name="Some1">Some examples</a></h3> 3387 3388<p>The directory <code>test/valid/dtds/</code> in the libxml2 distribution 3389contains some complex DTD examples. The example in the file 3390<code>test/valid/dia.xml</code> shows an XML file where the simple DTD is 3391directly included within the document.</p> 3392 3393<h3><a name="validate1">How to validate</a></h3> 3394 3395<p>The simplest way is to use the xmllint program included with libxml. The 3396<code>--valid</code> option turns-on validation of the files given as input. 3397For example the following validates a copy of the first revision of the XML 33981.0 specification:</p> 3399 3400<p><code>xmllint --valid --noout test/valid/REC-xml-19980210.xml</code></p> 3401 3402<p>the -- noout is used to disable output of the resulting tree.</p> 3403 3404<p>The <code>--dtdvalid dtd</code> allows validation of the document(s) 3405against a given DTD.</p> 3406 3407<p>Libxml2 exports an API to handle DTDs and validation, check the <a 3408href="http://xmlsoft.org/html/libxml-valid.html">associated 3409description</a>.</p> 3410 3411<h3><a name="Other1">Other resources</a></h3> 3412 3413<p>DTDs are as old as SGML. So there may be a number of examples on-line, I 3414will just list one for now, others pointers welcome:</p> 3415<ul> 3416 <li><a href="http://www.xml101.com:8081/dtd/">XML-101 DTD</a></li> 3417</ul> 3418 3419<p>I suggest looking at the examples found under test/valid/dtd and any of 3420the large number of books available on XML. The dia example in test/valid 3421should be both simple and complete enough to allow you to build your own.</p> 3422 3423<p></p> 3424 3425<h2><a name="Memory">Memory Management</a></h2> 3426 3427<p>Table of Content:</p> 3428<ol> 3429 <li><a href="#General3">General overview</a></li> 3430 <li><a href="#setting">Setting libxml2 set of memory routines</a></li> 3431 <li><a href="#cleanup">Cleaning up after using the library</a></li> 3432 <li><a href="#Debugging">Debugging routines</a></li> 3433 <li><a href="#General4">General memory requirements</a></li> 3434 <li><a href="#Compacting">Returning memory to the kernel</a></li> 3435</ol> 3436 3437<h3><a name="General3">General overview</a></h3> 3438 3439<p>The module <code><a 3440href="http://xmlsoft.org/html/libxml-xmlmemory.html">xmlmemory.h</a></code> 3441provides the interfaces to the libxml2 memory system:</p> 3442<ul> 3443 <li>libxml2 does not use the libc memory allocator directly but xmlFree(), 3444 xmlMalloc() and xmlRealloc()</li> 3445 <li>those routines can be reallocated to a specific set of routine, by 3446 default the libc ones i.e. free(), malloc() and realloc()</li> 3447 <li>the xmlmemory.c module includes a set of debugging routine</li> 3448</ul> 3449 3450<h3><a name="setting">Setting libxml2 set of memory routines</a></h3> 3451 3452<p>It is sometimes useful to not use the default memory allocator, either for 3453debugging, analysis or to implement a specific behaviour on memory management 3454(like on embedded systems). Two function calls are available to do so:</p> 3455<ul> 3456 <li><a href="http://xmlsoft.org/html/libxml-xmlmemory.html">xmlMemGet 3457 ()</a> which return the current set of functions in use by the parser</li> 3458 <li><a 3459 href="http://xmlsoft.org/html/libxml-xmlmemory.html">xmlMemSetup()</a> 3460 which allow to set up a new set of memory allocation functions</li> 3461</ul> 3462 3463<p>Of course a call to xmlMemSetup() should probably be done before calling 3464any other libxml2 routines (unless you are sure your allocations routines are 3465compatibles).</p> 3466 3467<h3><a name="cleanup">Cleaning up after using the library</a></h3> 3468 3469<p>Libxml2 is not stateless, there is a few set of memory structures needing 3470allocation before the parser is fully functional (some encoding structures 3471for example). This also mean that once parsing is finished there is a tiny 3472amount of memory (a few hundred bytes) which can be recollected if you don't 3473reuse the library or any document built with it:</p> 3474<ul> 3475 <li><a href="http://xmlsoft.org/html/libxml-parser.html">xmlCleanupParser 3476 ()</a> is a centralized routine to free the library state and data. Note 3477 that it won't deallocate any produced tree if any (use the xmlFreeDoc() 3478 and related routines for this). This should be called only when the library 3479 is not used anymore.</li> 3480 <li><a href="http://xmlsoft.org/html/libxml-parser.html">xmlInitParser 3481 ()</a> is the dual routine allowing to preallocate the parsing state 3482 which can be useful for example to avoid initialization reentrancy 3483 problems when using libxml2 in multithreaded applications</li> 3484</ul> 3485 3486<p>Generally xmlCleanupParser() is safe assuming no parsing is ongoing and 3487no document is still being used, if needed the state will be rebuild at the 3488next invocation of parser routines (or by xmlInitParser()), but be careful 3489of the consequences in multithreaded applications.</p> 3490 3491<h3><a name="Debugging">Debugging routines</a></h3> 3492 3493<p>When configured using --with-mem-debug flag (off by default), libxml2 uses 3494a set of memory allocation debugging routines keeping track of all allocated 3495blocks and the location in the code where the routine was called. A couple of 3496other debugging routines allow to dump the memory allocated infos to a file 3497or call a specific routine when a given block number is allocated:</p> 3498<ul> 3499 <li><a 3500 href="http://xmlsoft.org/html/libxml-xmlmemory.html">xmlMallocLoc()</a> 3501 <a 3502 href="http://xmlsoft.org/html/libxml-xmlmemory.html">xmlReallocLoc()</a> 3503 and <a 3504 href="http://xmlsoft.org/html/libxml-xmlmemory.html">xmlMemStrdupLoc()</a> 3505 are the memory debugging replacement allocation routines</li> 3506 <li><a href="http://xmlsoft.org/html/libxml-xmlmemory.html">xmlMemoryDump 3507 ()</a> dumps all the information about the allocated memory block lefts 3508 in the <code>.memdump</code> file</li> 3509</ul> 3510 3511<p>When developing libxml2 memory debug is enabled, the tests programs call 3512xmlMemoryDump () and the "make test" regression tests will check for any 3513memory leak during the full regression test sequence, this helps a lot 3514ensuring that libxml2 does not leak memory and bullet proof memory 3515allocations use (some libc implementations are known to be far too permissive 3516resulting in major portability problems!).</p> 3517 3518<p>If the .memdump reports a leak, it displays the allocation function and 3519also tries to give some information about the content and structure of the 3520allocated blocks left. This is sufficient in most cases to find the culprit, 3521but not always. Assuming the allocation problem is reproducible, it is 3522possible to find more easily:</p> 3523<ol> 3524 <li>write down the block number xxxx not allocated</li> 3525 <li>export the environment variable XML_MEM_BREAKPOINT=xxxx , the easiest 3526 when using GDB is to simply give the command 3527 <p><code>set environment XML_MEM_BREAKPOINT xxxx</code></p> 3528 <p>before running the program.</p> 3529 </li> 3530 <li>run the program under a debugger and set a breakpoint on 3531 xmlMallocBreakpoint() a specific function called when this precise block 3532 is allocated</li> 3533 <li>when the breakpoint is reached you can then do a fine analysis of the 3534 allocation an step to see the condition resulting in the missing 3535 deallocation.</li> 3536</ol> 3537 3538<p>I used to use a commercial tool to debug libxml2 memory problems but after 3539noticing that it was not detecting memory leaks that simple mechanism was 3540used and proved extremely efficient until now. Lately I have also used <a 3541href="http://developer.kde.org/~sewardj/">valgrind</a> with quite some 3542success, it is tied to the i386 architecture since it works by emulating the 3543processor and instruction set, it is slow but extremely efficient, i.e. it 3544spot memory usage errors in a very precise way.</p> 3545 3546<h3><a name="General4">General memory requirements</a></h3> 3547 3548<p>How much libxml2 memory require ? It's hard to tell in average it depends 3549of a number of things:</p> 3550<ul> 3551 <li>the parser itself should work in a fixed amount of memory, except for 3552 information maintained about the stacks of names and entities locations. 3553 The I/O and encoding handlers will probably account for a few KBytes. 3554 This is true for both the XML and HTML parser (though the HTML parser 3555 need more state).</li> 3556 <li>If you are generating the DOM tree then memory requirements will grow 3557 nearly linear with the size of the data. In general for a balanced 3558 textual document the internal memory requirement is about 4 times the 3559 size of the UTF8 serialization of this document (example the XML-1.0 3560 recommendation is a bit more of 150KBytes and takes 650KBytes of main 3561 memory when parsed). Validation will add a amount of memory required for 3562 maintaining the external Dtd state which should be linear with the 3563 complexity of the content model defined by the Dtd</li> 3564 <li>If you need to work with fixed memory requirements or don't need the 3565 full DOM tree then using the <a href="xmlreader.html">xmlReader 3566 interface</a> is probably the best way to proceed, it still allows to 3567 validate or operate on subset of the tree if needed.</li> 3568 <li>If you don't care about the advanced features of libxml2 like 3569 validation, DOM, XPath or XPointer, don't use entities, need to work with 3570 fixed memory requirements, and try to get the fastest parsing possible 3571 then the SAX interface should be used, but it has known restrictions.</li> 3572</ul> 3573 3574<p></p> 3575<h3><a name="Compacting">Returning memory to the kernel</a></h3> 3576 3577<p>You may encounter that your process using libxml2 does not have a 3578reduced memory usage although you freed the trees. This is because 3579libxml2 allocates memory in a number of small chunks. When freeing one 3580of those chunks, the OS may decide that giving this little memory back 3581to the kernel will cause too much overhead and delay the operation. As 3582all chunks are this small, they get actually freed but not returned to 3583the kernel. On systems using glibc, there is a function call 3584"malloc_trim" from malloc.h which does this missing operation (note that 3585it is allowed to fail). Thus, after freeing your tree you may simply try 3586"malloc_trim(0);" to really get the memory back. If your OS does not 3587provide malloc_trim, try searching for a similar function.</p> 3588<p></p> 3589 3590<h2><a name="Encodings">Encodings support</a></h2> 3591 3592<p>If you are not really familiar with Internationalization (usual shortcut 3593is I18N) , Unicode, characters and glyphs, I suggest you read a <a 3594href="http://www.tbray.org/ongoing/When/200x/2003/04/06/Unicode">presentation</a> 3595by Tim Bray on Unicode and why you should care about it.</p> 3596 3597<p>If you don't understand why <b>it does not make sense to have a string 3598without knowing what encoding it uses</b>, then as Joel Spolsky said <a 3599href="http://www.joelonsoftware.com/articles/Unicode.html">please do not 3600write another line of code until you finish reading that article.</a>. It is 3601a prerequisite to understand this page, and avoid a lot of problems with 3602libxml2, XML or text processing in general.</p> 3603 3604<p>Table of Content:</p> 3605<ol> 3606 <li><a href="encoding.html#What">What does internationalization support 3607 mean ?</a></li> 3608 <li><a href="encoding.html#internal">The internal encoding, how and 3609 why</a></li> 3610 <li><a href="encoding.html#implemente">How is it implemented ?</a></li> 3611 <li><a href="encoding.html#Default">Default supported encodings</a></li> 3612 <li><a href="encoding.html#extend">How to extend the existing 3613 support</a></li> 3614</ol> 3615 3616<h3><a name="What">What does internationalization support mean ?</a></h3> 3617 3618<p>XML was designed from the start to allow the support of any character set 3619by using Unicode. Any conformant XML parser has to support the UTF-8 and 3620UTF-16 default encodings which can both express the full unicode ranges. UTF8 3621is a variable length encoding whose greatest points are to reuse the same 3622encoding for ASCII and to save space for Western encodings, but it is a bit 3623more complex to handle in practice. UTF-16 use 2 bytes per character (and 3624sometimes combines two pairs), it makes implementation easier, but looks a 3625bit overkill for Western languages encoding. Moreover the XML specification 3626allows the document to be encoded in other encodings at the condition that 3627they are clearly labeled as such. For example the following is a wellformed 3628XML document encoded in ISO-8859-1 and using accentuated letters that we 3629French like for both markup and content:</p> 3630<pre><?xml version="1.0" encoding="ISO-8859-1"?> 3631<tr�s>l�</tr�s></pre> 3632 3633<p>Having internationalization support in libxml2 means the following:</p> 3634<ul> 3635 <li>the document is properly parsed</li> 3636 <li>information about it's encoding is saved</li> 3637 <li>it can be modified</li> 3638 <li>it can be saved in its original encoding</li> 3639 <li>it can also be saved in another encoding supported by libxml2 (for 3640 example straight UTF8 or even an ASCII form)</li> 3641</ul> 3642 3643<p>Another very important point is that the whole libxml2 API, with the 3644exception of a few routines to read with a specific encoding or save to a 3645specific encoding, is completely agnostic about the original encoding of the 3646document.</p> 3647 3648<p>It should be noted too that the HTML parser embedded in libxml2 now obey 3649the same rules too, the following document will be (as of 2.2.2) handled in 3650an internationalized fashion by libxml2 too:</p> 3651<pre><!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN" 3652 "http://www.w3.org/TR/REC-html40/loose.dtd"> 3653<html lang="fr"> 3654<head> 3655 <META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=ISO-8859-1"> 3656</head> 3657<body> 3658<p>W3C cr�e des standards pour le Web.</body> 3659</html></pre> 3660 3661<h3><a name="internal">The internal encoding, how and why</a></h3> 3662 3663<p>One of the core decisions was to force all documents to be converted to a 3664default internal encoding, and that encoding to be UTF-8, here are the 3665rationales for those choices:</p> 3666<ul> 3667 <li>keeping the native encoding in the internal form would force the libxml 3668 users (or the code associated) to be fully aware of the encoding of the 3669 original document, for examples when adding a text node to a document, 3670 the content would have to be provided in the document encoding, i.e. the 3671 client code would have to check it before hand, make sure it's conformant 3672 to the encoding, etc ... Very hard in practice, though in some specific 3673 cases this may make sense.</li> 3674 <li>the second decision was which encoding. From the XML spec only UTF8 and 3675 UTF16 really makes sense as being the two only encodings for which there 3676 is mandatory support. UCS-4 (32 bits fixed size encoding) could be 3677 considered an intelligent choice too since it's a direct Unicode mapping 3678 support. I selected UTF-8 on the basis of efficiency and compatibility 3679 with surrounding software: 3680 <ul> 3681 <li>UTF-8 while a bit more complex to convert from/to (i.e. slightly 3682 more costly to import and export CPU wise) is also far more compact 3683 than UTF-16 (and UCS-4) for a majority of the documents I see it used 3684 for right now (RPM RDF catalogs, advogato data, various configuration 3685 file formats, etc.) and the key point for today's computer 3686 architecture is efficient uses of caches. If one nearly double the 3687 memory requirement to store the same amount of data, this will trash 3688 caches (main memory/external caches/internal caches) and my take is 3689 that this harms the system far more than the CPU requirements needed 3690 for the conversion to UTF-8</li> 3691 <li>Most of libxml2 version 1 users were using it with straight ASCII 3692 most of the time, doing the conversion with an internal encoding 3693 requiring all their code to be rewritten was a serious show-stopper 3694 for using UTF-16 or UCS-4.</li> 3695 <li>UTF-8 is being used as the de-facto internal encoding standard for 3696 related code like the <a href="http://www.pango.org/">pango</a> 3697 upcoming Gnome text widget, and a lot of Unix code (yet another place 3698 where Unix programmer base takes a different approach from Microsoft 3699 - they are using UTF-16)</li> 3700 </ul> 3701 </li> 3702</ul> 3703 3704<p>What does this mean in practice for the libxml2 user:</p> 3705<ul> 3706 <li>xmlChar, the libxml2 data type is a byte, those bytes must be assembled 3707 as UTF-8 valid strings. The proper way to terminate an xmlChar * string 3708 is simply to append 0 byte, as usual.</li> 3709 <li>One just need to make sure that when using chars outside the ASCII set, 3710 the values has been properly converted to UTF-8</li> 3711</ul> 3712 3713<h3><a name="implemente">How is it implemented ?</a></h3> 3714 3715<p>Let's describe how all this works within libxml, basically the I18N 3716(internationalization) support get triggered only during I/O operation, i.e. 3717when reading a document or saving one. Let's look first at the reading 3718sequence:</p> 3719<ol> 3720 <li>when a document is processed, we usually don't know the encoding, a 3721 simple heuristic allows to detect UTF-16 and UCS-4 from encodings where 3722 the ASCII range (0-0x7F) maps with ASCII</li> 3723 <li>the xml declaration if available is parsed, including the encoding 3724 declaration. At that point, if the autodetected encoding is different 3725 from the one declared a call to xmlSwitchEncoding() is issued.</li> 3726 <li>If there is no encoding declaration, then the input has to be in either 3727 UTF-8 or UTF-16, if it is not then at some point when processing the 3728 input, the converter/checker of UTF-8 form will raise an encoding error. 3729 You may end-up with a garbled document, or no document at all ! Example: 3730 <pre>~/XML -> ./xmllint err.xml 3731err.xml:1: error: Input is not proper UTF-8, indicate encoding ! 3732<tr�s>l�</tr�s> 3733 ^ 3734err.xml:1: error: Bytes: 0xE8 0x73 0x3E 0x6C 3735<tr�s>l�</tr�s> 3736 ^</pre> 3737 </li> 3738 <li>xmlSwitchEncoding() does an encoding name lookup, canonicalize it, and 3739 then search the default registered encoding converters for that encoding. 3740 If it's not within the default set and iconv() support has been compiled 3741 it, it will ask iconv for such an encoder. If this fails then the parser 3742 will report an error and stops processing: 3743 <pre>~/XML -> ./xmllint err2.xml 3744err2.xml:1: error: Unsupported encoding UnsupportedEnc 3745<?xml version="1.0" encoding="UnsupportedEnc"?> 3746 ^</pre> 3747 </li> 3748 <li>From that point the encoder processes progressively the input (it is 3749 plugged as a front-end to the I/O module) for that entity. It captures 3750 and converts on-the-fly the document to be parsed to UTF-8. The parser 3751 itself just does UTF-8 checking of this input and process it 3752 transparently. The only difference is that the encoding information has 3753 been added to the parsing context (more precisely to the input 3754 corresponding to this entity).</li> 3755 <li>The result (when using DOM) is an internal form completely in UTF-8 3756 with just an encoding information on the document node.</li> 3757</ol> 3758 3759<p>Ok then what happens when saving the document (assuming you 3760collected/built an xmlDoc DOM like structure) ? It depends on the function 3761called, xmlSaveFile() will just try to save in the original encoding, while 3762xmlSaveFileTo() and xmlSaveFileEnc() can optionally save to a given 3763encoding:</p> 3764<ol> 3765 <li>if no encoding is given, libxml2 will look for an encoding value 3766 associated to the document and if it exists will try to save to that 3767 encoding, 3768 <p>otherwise everything is written in the internal form, i.e. UTF-8</p> 3769 </li> 3770 <li>so if an encoding was specified, either at the API level or on the 3771 document, libxml2 will again canonicalize the encoding name, lookup for a 3772 converter in the registered set or through iconv. If not found the 3773 function will return an error code</li> 3774 <li>the converter is placed before the I/O buffer layer, as another kind of 3775 buffer, then libxml2 will simply push the UTF-8 serialization to through 3776 that buffer, which will then progressively be converted and pushed onto 3777 the I/O layer.</li> 3778 <li>It is possible that the converter code fails on some input, for example 3779 trying to push an UTF-8 encoded Chinese character through the UTF-8 to 3780 ISO-8859-1 converter won't work. Since the encoders are progressive they 3781 will just report the error and the number of bytes converted, at that 3782 point libxml2 will decode the offending character, remove it from the 3783 buffer and replace it with the associated charRef encoding &#123; and 3784 resume the conversion. This guarantees that any document will be saved 3785 without losses (except for markup names where this is not legal, this is 3786 a problem in the current version, in practice avoid using non-ascii 3787 characters for tag or attribute names). A special "ascii" encoding name 3788 is used to save documents to a pure ascii form can be used when 3789 portability is really crucial</li> 3790</ol> 3791 3792<p>Here are a few examples based on the same test document:</p> 3793<pre>~/XML -> ./xmllint isolat1 3794<?xml version="1.0" encoding="ISO-8859-1"?> 3795<tr�s>l�</tr�s> 3796~/XML -> ./xmllint --encode UTF-8 isolat1 3797<?xml version="1.0" encoding="UTF-8"?> 3798<tr��s>l� </tr��s> 3799~/XML -> </pre> 3800 3801<p>The same processing is applied (and reuse most of the code) for HTML I18N 3802processing. Looking up and modifying the content encoding is a bit more 3803difficult since it is located in a <meta> tag under the <head>, 3804so a couple of functions htmlGetMetaEncoding() and htmlSetMetaEncoding() have 3805been provided. The parser also attempts to switch encoding on the fly when 3806detecting such a tag on input. Except for that the processing is the same 3807(and again reuses the same code).</p> 3808 3809<h3><a name="Default">Default supported encodings</a></h3> 3810 3811<p>libxml2 has a set of default converters for the following encodings 3812(located in encoding.c):</p> 3813<ol> 3814 <li>UTF-8 is supported by default (null handlers)</li> 3815 <li>UTF-16, both little and big endian</li> 3816 <li>ISO-Latin-1 (ISO-8859-1) covering most western languages</li> 3817 <li>ASCII, useful mostly for saving</li> 3818 <li>HTML, a specific handler for the conversion of UTF-8 to ASCII with HTML 3819 predefined entities like &copy; for the Copyright sign.</li> 3820</ol> 3821 3822<p>More over when compiled on an Unix platform with iconv support the full 3823set of encodings supported by iconv can be instantly be used by libxml. On a 3824linux machine with glibc-2.1 the list of supported encodings and aliases fill 38253 full pages, and include UCS-4, the full set of ISO-Latin encodings, and the 3826various Japanese ones.</p> 3827 3828<p>To convert from the UTF-8 values returned from the API to another encoding 3829then it is possible to use the function provided from <a 3830href="html/libxml-encoding.html">the encoding module</a> like <a 3831href="html/libxml-encoding.html#UTF8Toisolat1">UTF8Toisolat1</a>, or use the 3832POSIX <a 3833href="http://www.opengroup.org/onlinepubs/009695399/functions/iconv.html">iconv()</a> 3834API directly.</p> 3835 3836<h4>Encoding aliases</h4> 3837 3838<p>From 2.2.3, libxml2 has support to register encoding names aliases. The 3839goal is to be able to parse document whose encoding is supported but where 3840the name differs (for example from the default set of names accepted by 3841iconv). The following functions allow to register and handle new aliases for 3842existing encodings. Once registered libxml2 will automatically lookup the 3843aliases when handling a document:</p> 3844<ul> 3845 <li>int xmlAddEncodingAlias(const char *name, const char *alias);</li> 3846 <li>int xmlDelEncodingAlias(const char *alias);</li> 3847 <li>const char * xmlGetEncodingAlias(const char *alias);</li> 3848 <li>void xmlCleanupEncodingAliases(void);</li> 3849</ul> 3850 3851<h3><a name="extend">How to extend the existing support</a></h3> 3852 3853<p>Well adding support for new encoding, or overriding one of the encoders 3854(assuming it is buggy) should not be hard, just write input and output 3855conversion routines to/from UTF-8, and register them using 3856xmlNewCharEncodingHandler(name, xxxToUTF8, UTF8Toxxx), and they will be 3857called automatically if the parser(s) encounter such an encoding name 3858(register it uppercase, this will help). The description of the encoders, 3859their arguments and expected return values are described in the encoding.h 3860header.</p> 3861 3862<h2><a name="IO">I/O Interfaces</a></h2> 3863 3864<p>Table of Content:</p> 3865<ol> 3866 <li><a href="#General1">General overview</a></li> 3867 <li><a href="#basic">The basic buffer type</a></li> 3868 <li><a href="#Input">Input I/O handlers</a></li> 3869 <li><a href="#Output">Output I/O handlers</a></li> 3870 <li><a href="#entities">The entities loader</a></li> 3871 <li><a href="#Example2">Example of customized I/O</a></li> 3872</ol> 3873 3874<h3><a name="General1">General overview</a></h3> 3875 3876<p>The module <code><a 3877href="http://xmlsoft.org/html/libxml-xmlio.html">xmlIO.h</a></code> provides 3878the interfaces to the libxml2 I/O system. This consists of 4 main parts:</p> 3879<ul> 3880 <li>Entities loader, this is a routine which tries to fetch the entities 3881 (files) based on their PUBLIC and SYSTEM identifiers. The default loader 3882 don't look at the public identifier since libxml2 do not maintain a 3883 catalog. You can redefine you own entity loader by using 3884 <code>xmlGetExternalEntityLoader()</code> and 3885 <code>xmlSetExternalEntityLoader()</code>. <a href="#entities">Check the 3886 example</a>.</li> 3887 <li>Input I/O buffers which are a commodity structure used by the parser(s) 3888 input layer to handle fetching the information to feed the parser. This 3889 provides buffering and is also a placeholder where the encoding 3890 converters to UTF8 are piggy-backed.</li> 3891 <li>Output I/O buffers are similar to the Input ones and fulfill similar 3892 task but when generating a serialization from a tree.</li> 3893 <li>A mechanism to register sets of I/O callbacks and associate them with 3894 specific naming schemes like the protocol part of the URIs. 3895 <p>This affect the default I/O operations and allows to use specific I/O 3896 handlers for certain names.</p> 3897 </li> 3898</ul> 3899 3900<p>The general mechanism used when loading http://rpmfind.net/xml.html for 3901example in the HTML parser is the following:</p> 3902<ol> 3903 <li>The default entity loader calls <code>xmlNewInputFromFile()</code> with 3904 the parsing context and the URI string.</li> 3905 <li>the URI string is checked against the existing registered handlers 3906 using their match() callback function, if the HTTP module was compiled 3907 in, it is registered and its match() function will succeeds</li> 3908 <li>the open() function of the handler is called and if successful will 3909 return an I/O Input buffer</li> 3910 <li>the parser will the start reading from this buffer and progressively 3911 fetch information from the resource, calling the read() function of the 3912 handler until the resource is exhausted</li> 3913 <li>if an encoding change is detected it will be installed on the input 3914 buffer, providing buffering and efficient use of the conversion 3915 routines</li> 3916 <li>once the parser has finished, the close() function of the handler is 3917 called once and the Input buffer and associated resources are 3918 deallocated.</li> 3919</ol> 3920 3921<p>The user defined callbacks are checked first to allow overriding of the 3922default libxml2 I/O routines.</p> 3923 3924<h3><a name="basic">The basic buffer type</a></h3> 3925 3926<p>All the buffer manipulation handling is done using the 3927<code>xmlBuffer</code> type define in <code><a 3928href="http://xmlsoft.org/html/libxml-tree.html">tree.h</a> </code>which is a 3929resizable memory buffer. The buffer allocation strategy can be selected to be 3930either best-fit or use an exponential doubling one (CPU vs. memory use 3931trade-off). The values are <code>XML_BUFFER_ALLOC_EXACT</code> and 3932<code>XML_BUFFER_ALLOC_DOUBLEIT</code>, and can be set individually or on a 3933system wide basis using <code>xmlBufferSetAllocationScheme()</code>. A number 3934of functions allows to manipulate buffers with names starting with the 3935<code>xmlBuffer...</code> prefix.</p> 3936 3937<h3><a name="Input">Input I/O handlers</a></h3> 3938 3939<p>An Input I/O handler is a simple structure 3940<code>xmlParserInputBuffer</code> containing a context associated to the 3941resource (file descriptor, or pointer to a protocol handler), the read() and 3942close() callbacks to use and an xmlBuffer. And extra xmlBuffer and a charset 3943encoding handler are also present to support charset conversion when 3944needed.</p> 3945 3946<h3><a name="Output">Output I/O handlers</a></h3> 3947 3948<p>An Output handler <code>xmlOutputBuffer</code> is completely similar to an 3949Input one except the callbacks are write() and close().</p> 3950 3951<h3><a name="entities">The entities loader</a></h3> 3952 3953<p>The entity loader resolves requests for new entities and create inputs for 3954the parser. Creating an input from a filename or an URI string is done 3955through the xmlNewInputFromFile() routine. The default entity loader do not 3956handle the PUBLIC identifier associated with an entity (if any). So it just 3957calls xmlNewInputFromFile() with the SYSTEM identifier (which is mandatory in 3958XML).</p> 3959 3960<p>If you want to hook up a catalog mechanism then you simply need to 3961override the default entity loader, here is an example:</p> 3962<pre>#include <libxml/xmlIO.h> 3963 3964xmlExternalEntityLoader defaultLoader = NULL; 3965 3966xmlParserInputPtr 3967xmlMyExternalEntityLoader(const char *URL, const char *ID, 3968 xmlParserCtxtPtr ctxt) { 3969 xmlParserInputPtr ret; 3970 const char *fileID = NULL; 3971 /* lookup for the fileID depending on ID */ 3972 3973 ret = xmlNewInputFromFile(ctxt, fileID); 3974 if (ret != NULL) 3975 return(ret); 3976 if (defaultLoader != NULL) 3977 ret = defaultLoader(URL, ID, ctxt); 3978 return(ret); 3979} 3980 3981int main(..) { 3982 ... 3983 3984 /* 3985 * Install our own entity loader 3986 */ 3987 defaultLoader = xmlGetExternalEntityLoader(); 3988 xmlSetExternalEntityLoader(xmlMyExternalEntityLoader); 3989 3990 ... 3991}</pre> 3992 3993<h3><a name="Example2">Example of customized I/O</a></h3> 3994 3995<p>This example come from <a href="http://xmlsoft.org/messages/0708.html">a 3996real use case</a>, xmlDocDump() closes the FILE * passed by the application 3997and this was a problem. The <a 3998href="http://xmlsoft.org/messages/0711.html">solution</a> was to redefine a 3999new output handler with the closing call deactivated:</p> 4000<ol> 4001 <li>First define a new I/O output allocator where the output don't close 4002 the file: 4003 <pre>xmlOutputBufferPtr 4004xmlOutputBufferCreateOwn(FILE *file, xmlCharEncodingHandlerPtr encoder) { 4005 xmlOutputBufferPtr ret; 4006 4007 if (xmlOutputCallbackInitialized == 0) 4008 xmlRegisterDefaultOutputCallbacks(); 4009 4010 if (file == NULL) return(NULL); 4011 ret = xmlAllocOutputBuffer(encoder); 4012 if (ret != NULL) { 4013 ret->context = file; 4014 ret->writecallback = xmlFileWrite; 4015 ret->closecallback = NULL; /* No close callback */ 4016 } 4017 return(ret); 4018} </pre> 4019 </li> 4020 <li>And then use it to save the document: 4021 <pre>FILE *f; 4022xmlOutputBufferPtr output; 4023xmlDocPtr doc; 4024int res; 4025 4026f = ... 4027doc = .... 4028 4029output = xmlOutputBufferCreateOwn(f, NULL); 4030res = xmlSaveFileTo(output, doc, NULL); 4031 </pre> 4032 </li> 4033</ol> 4034 4035<h2><a name="Catalog">Catalog support</a></h2> 4036 4037<p>Table of Content:</p> 4038<ol> 4039 <li><a href="General2">General overview</a></li> 4040 <li><a href="#definition">The definition</a></li> 4041 <li><a href="#Simple">Using catalogs</a></li> 4042 <li><a href="#Some">Some examples</a></li> 4043 <li><a href="#reference">How to tune catalog usage</a></li> 4044 <li><a href="#validate">How to debug catalog processing</a></li> 4045 <li><a href="#Declaring">How to create and maintain catalogs</a></li> 4046 <li><a href="#implemento">The implementor corner quick review of the 4047 API</a></li> 4048 <li><a href="#Other">Other resources</a></li> 4049</ol> 4050 4051<h3><a name="General2">General overview</a></h3> 4052 4053<p>What is a catalog? Basically it's a lookup mechanism used when an entity 4054(a file or a remote resource) references another entity. The catalog lookup 4055is inserted between the moment the reference is recognized by the software 4056(XML parser, stylesheet processing, or even images referenced for inclusion 4057in a rendering) and the time where loading that resource is actually 4058started.</p> 4059 4060<p>It is basically used for 3 things:</p> 4061<ul> 4062 <li>mapping from "logical" names, the public identifiers and a more 4063 concrete name usable for download (and URI). For example it can associate 4064 the logical name 4065 <p>"-//OASIS//DTD DocBook XML V4.1.2//EN"</p> 4066 <p>of the DocBook 4.1.2 XML DTD with the actual URL where it can be 4067 downloaded</p> 4068 <p>http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd</p> 4069 </li> 4070 <li>remapping from a given URL to another one, like an HTTP indirection 4071 saying that 4072 <p>"http://www.oasis-open.org/committes/tr.xsl"</p> 4073 <p>should really be looked at</p> 4074 <p>"http://www.oasis-open.org/committes/entity/stylesheets/base/tr.xsl"</p> 4075 </li> 4076 <li>providing a local cache mechanism allowing to load the entities 4077 associated to public identifiers or remote resources, this is a really 4078 important feature for any significant deployment of XML or SGML since it 4079 allows to avoid the aleas and delays associated to fetching remote 4080 resources.</li> 4081</ul> 4082 4083<h3><a name="definition">The definitions</a></h3> 4084 4085<p>Libxml, as of 2.4.3 implements 2 kind of catalogs:</p> 4086<ul> 4087 <li>the older SGML catalogs, the official spec is SGML Open Technical 4088 Resolution TR9401:1997, but is better understood by reading <a 4089 href="http://www.jclark.com/sp/catalog.htm">the SP Catalog page</a> from 4090 James Clark. This is relatively old and not the preferred mode of 4091 operation of libxml.</li> 4092 <li><a href="http://www.oasis-open.org/committees/entity/spec.html">XML 4093 Catalogs</a> is far more flexible, more recent, uses an XML syntax and 4094 should scale quite better. This is the default option of libxml.</li> 4095</ul> 4096 4097<p></p> 4098 4099<h3><a name="Simple">Using catalog</a></h3> 4100 4101<p>In a normal environment libxml2 will by default check the presence of a 4102catalog in /etc/xml/catalog, and assuming it has been correctly populated, 4103the processing is completely transparent to the document user. To take a 4104concrete example, suppose you are authoring a DocBook document, this one 4105starts with the following DOCTYPE definition:</p> 4106<pre><?xml version='1.0'?> 4107<!DOCTYPE book PUBLIC "-//Norman Walsh//DTD DocBk XML V3.1.4//EN" 4108 "http://nwalsh.com/docbook/xml/3.1.4/db3xml.dtd"></pre> 4109 4110<p>When validating the document with libxml, the catalog will be 4111automatically consulted to lookup the public identifier "-//Norman Walsh//DTD 4112DocBk XML V3.1.4//EN" and the system identifier 4113"http://nwalsh.com/docbook/xml/3.1.4/db3xml.dtd", and if these entities have 4114been installed on your system and the catalogs actually point to them, libxml 4115will fetch them from the local disk.</p> 4116 4117<p style="font-size: 10pt"><strong>Note</strong>: Really don't use this 4118DOCTYPE example it's a really old version, but is fine as an example.</p> 4119 4120<p>Libxml2 will check the catalog each time that it is requested to load an 4121entity, this includes DTD, external parsed entities, stylesheets, etc ... If 4122your system is correctly configured all the authoring phase and processing 4123should use only local files, even if your document stays portable because it 4124uses the canonical public and system ID, referencing the remote document.</p> 4125 4126<h3><a name="Some">Some examples:</a></h3> 4127 4128<p>Here is a couple of fragments from XML Catalogs used in libxml2 early 4129regression tests in <code>test/catalogs</code> :</p> 4130<pre><?xml version="1.0"?> 4131<!DOCTYPE catalog PUBLIC 4132 "-//OASIS//DTD Entity Resolution XML Catalog V1.0//EN" 4133 "http://www.oasis-open.org/committees/entity/release/1.0/catalog.dtd"> 4134<catalog xmlns="urn:oasis:names:tc:entity:xmlns:xml:catalog"> 4135 <public publicId="-//OASIS//DTD DocBook XML V4.1.2//EN" 4136 uri="http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd"/> 4137...</pre> 4138 4139<p>This is the beginning of a catalog for DocBook 4.1.2, XML Catalogs are 4140written in XML, there is a specific namespace for catalog elements 4141"urn:oasis:names:tc:entity:xmlns:xml:catalog". The first entry in this 4142catalog is a <code>public</code> mapping it allows to associate a Public 4143Identifier with an URI.</p> 4144<pre>... 4145 <rewriteSystem systemIdStartString="http://www.oasis-open.org/docbook/" 4146 rewritePrefix="file:///usr/share/xml/docbook/"/> 4147...</pre> 4148 4149<p>A <code>rewriteSystem</code> is a very powerful instruction, it says that 4150any URI starting with a given prefix should be looked at another URI 4151constructed by replacing the prefix with an new one. In effect this acts like 4152a cache system for a full area of the Web. In practice it is extremely useful 4153with a file prefix if you have installed a copy of those resources on your 4154local system.</p> 4155<pre>... 4156<delegatePublic publicIdStartString="-//OASIS//DTD XML Catalog //" 4157 catalog="file:///usr/share/xml/docbook.xml"/> 4158<delegatePublic publicIdStartString="-//OASIS//ENTITIES DocBook XML" 4159 catalog="file:///usr/share/xml/docbook.xml"/> 4160<delegatePublic publicIdStartString="-//OASIS//DTD DocBook XML" 4161 catalog="file:///usr/share/xml/docbook.xml"/> 4162<delegateSystem systemIdStartString="http://www.oasis-open.org/docbook/" 4163 catalog="file:///usr/share/xml/docbook.xml"/> 4164<delegateURI uriStartString="http://www.oasis-open.org/docbook/" 4165 catalog="file:///usr/share/xml/docbook.xml"/> 4166...</pre> 4167 4168<p>Delegation is the core features which allows to build a tree of catalogs, 4169easier to maintain than a single catalog, based on Public Identifier, System 4170Identifier or URI prefixes it instructs the catalog software to look up 4171entries in another resource. This feature allow to build hierarchies of 4172catalogs, the set of entries presented should be sufficient to redirect the 4173resolution of all DocBook references to the specific catalog in 4174<code>/usr/share/xml/docbook.xml</code> this one in turn could delegate all 4175references for DocBook 4.2.1 to a specific catalog installed at the same time 4176as the DocBook resources on the local machine.</p> 4177 4178<h3><a name="reference">How to tune catalog usage:</a></h3> 4179 4180<p>The user can change the default catalog behaviour by redirecting queries 4181to its own set of catalogs, this can be done by setting the 4182<code>XML_CATALOG_FILES</code> environment variable to a list of catalogs, an 4183empty one should deactivate loading the default <code>/etc/xml/catalog</code> 4184default catalog</p> 4185 4186<h3><a name="validate">How to debug catalog processing:</a></h3> 4187 4188<p>Setting up the <code>XML_DEBUG_CATALOG</code> environment variable will 4189make libxml2 output debugging information for each catalog operations, for 4190example:</p> 4191<pre>orchis:~/XML -> xmllint --memory --noout test/ent2 4192warning: failed to load external entity "title.xml" 4193orchis:~/XML -> export XML_DEBUG_CATALOG= 4194orchis:~/XML -> xmllint --memory --noout test/ent2 4195Failed to parse catalog /etc/xml/catalog 4196Failed to parse catalog /etc/xml/catalog 4197warning: failed to load external entity "title.xml" 4198Catalogs cleanup 4199orchis:~/XML -> </pre> 4200 4201<p>The test/ent2 references an entity, running the parser from memory makes 4202the base URI unavailable and the the "title.xml" entity cannot be loaded. 4203Setting up the debug environment variable allows to detect that an attempt is 4204made to load the <code>/etc/xml/catalog</code> but since it's not present the 4205resolution fails.</p> 4206 4207<p>But the most advanced way to debug XML catalog processing is to use the 4208<strong>xmlcatalog</strong> command shipped with libxml2, it allows to load 4209catalogs and make resolution queries to see what is going on. This is also 4210used for the regression tests:</p> 4211<pre>orchis:~/XML -> ./xmlcatalog test/catalogs/docbook.xml \ 4212 "-//OASIS//DTD DocBook XML V4.1.2//EN" 4213http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd 4214orchis:~/XML -> </pre> 4215 4216<p>For debugging what is going on, adding one -v flags increase the verbosity 4217level to indicate the processing done (adding a second flag also indicate 4218what elements are recognized at parsing):</p> 4219<pre>orchis:~/XML -> ./xmlcatalog -v test/catalogs/docbook.xml \ 4220 "-//OASIS//DTD DocBook XML V4.1.2//EN" 4221Parsing catalog test/catalogs/docbook.xml's content 4222Found public match -//OASIS//DTD DocBook XML V4.1.2//EN 4223http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd 4224Catalogs cleanup 4225orchis:~/XML -> </pre> 4226 4227<p>A shell interface is also available to debug and process multiple queries 4228(and for regression tests):</p> 4229<pre>orchis:~/XML -> ./xmlcatalog -shell test/catalogs/docbook.xml \ 4230 "-//OASIS//DTD DocBook XML V4.1.2//EN" 4231> help 4232Commands available: 4233public PublicID: make a PUBLIC identifier lookup 4234system SystemID: make a SYSTEM identifier lookup 4235resolve PublicID SystemID: do a full resolver lookup 4236add 'type' 'orig' 'replace' : add an entry 4237del 'values' : remove values 4238dump: print the current catalog state 4239debug: increase the verbosity level 4240quiet: decrease the verbosity level 4241exit: quit the shell 4242> public "-//OASIS//DTD DocBook XML V4.1.2//EN" 4243http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd 4244> quit 4245orchis:~/XML -> </pre> 4246 4247<p>This should be sufficient for most debugging purpose, this was actually 4248used heavily to debug the XML Catalog implementation itself.</p> 4249 4250<h3><a name="Declaring">How to create and maintain</a> catalogs:</h3> 4251 4252<p>Basically XML Catalogs are XML files, you can either use XML tools to 4253manage them or use <strong>xmlcatalog</strong> for this. The basic step is 4254to create a catalog the -create option provide this facility:</p> 4255<pre>orchis:~/XML -> ./xmlcatalog --create tst.xml 4256<?xml version="1.0"?> 4257<!DOCTYPE catalog PUBLIC "-//OASIS//DTD Entity Resolution XML Catalog V1.0//EN" 4258 "http://www.oasis-open.org/committees/entity/release/1.0/catalog.dtd"> 4259<catalog xmlns="urn:oasis:names:tc:entity:xmlns:xml:catalog"/> 4260orchis:~/XML -> </pre> 4261 4262<p>By default xmlcatalog does not overwrite the original catalog and save the 4263result on the standard output, this can be overridden using the -noout 4264option. The <code>-add</code> command allows to add entries in the 4265catalog:</p> 4266<pre>orchis:~/XML -> ./xmlcatalog --noout --create --add "public" \ 4267 "-//OASIS//DTD DocBook XML V4.1.2//EN" \ 4268 http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd tst.xml 4269orchis:~/XML -> cat tst.xml 4270<?xml version="1.0"?> 4271<!DOCTYPE catalog PUBLIC "-//OASIS//DTD Entity Resolution XML Catalog V1.0//EN" \ 4272 "http://www.oasis-open.org/committees/entity/release/1.0/catalog.dtd"> 4273<catalog xmlns="urn:oasis:names:tc:entity:xmlns:xml:catalog"> 4274<public publicId="-//OASIS//DTD DocBook XML V4.1.2//EN" 4275 uri="http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd"/> 4276</catalog> 4277orchis:~/XML -> </pre> 4278 4279<p>The <code>-add</code> option will always take 3 parameters even if some of 4280the XML Catalog constructs (like nextCatalog) will have only a single 4281argument, just pass a third empty string, it will be ignored.</p> 4282 4283<p>Similarly the <code>-del</code> option remove matching entries from the 4284catalog:</p> 4285<pre>orchis:~/XML -> ./xmlcatalog --del \ 4286 "http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd" tst.xml 4287<?xml version="1.0"?> 4288<!DOCTYPE catalog PUBLIC "-//OASIS//DTD Entity Resolution XML Catalog V1.0//EN" 4289 "http://www.oasis-open.org/committees/entity/release/1.0/catalog.dtd"> 4290<catalog xmlns="urn:oasis:names:tc:entity:xmlns:xml:catalog"/> 4291orchis:~/XML -> </pre> 4292 4293<p>The catalog is now empty. Note that the matching of <code>-del</code> is 4294exact and would have worked in a similar fashion with the Public ID 4295string.</p> 4296 4297<p>This is rudimentary but should be sufficient to manage a not too complex 4298catalog tree of resources.</p> 4299 4300<h3><a name="implemento">The implementor corner quick review of the 4301API:</a></h3> 4302 4303<p>First, and like for every other module of libxml, there is an 4304automatically generated <a href="html/libxml-catalog.html">API page for 4305catalog support</a>.</p> 4306 4307<p>The header for the catalog interfaces should be included as:</p> 4308<pre>#include <libxml/catalog.h></pre> 4309 4310<p>The API is voluntarily kept very simple. First it is not obvious that 4311applications really need access to it since it is the default behaviour of 4312libxml2 (Note: it is possible to completely override libxml2 default catalog 4313by using <a href="html/libxml-parser.html">xmlSetExternalEntityLoader</a> to 4314plug an application specific resolver).</p> 4315 4316<p>Basically libxml2 support 2 catalog lists:</p> 4317<ul> 4318 <li>the default one, global shared by all the application</li> 4319 <li>a per-document catalog, this one is built if the document uses the 4320 <code>oasis-xml-catalog</code> PIs to specify its own catalog list, it is 4321 associated to the parser context and destroyed when the parsing context 4322 is destroyed.</li> 4323</ul> 4324 4325<p>the document one will be used first if it exists.</p> 4326 4327<h4>Initialization routines:</h4> 4328 4329<p>xmlInitializeCatalog(), xmlLoadCatalog() and xmlLoadCatalogs() should be 4330used at startup to initialize the catalog, if the catalog should be 4331initialized with specific values xmlLoadCatalog() or xmlLoadCatalogs() 4332should be called before xmlInitializeCatalog() which would otherwise do a 4333default initialization first.</p> 4334 4335<p>The xmlCatalogAddLocal() call is used by the parser to grow the document 4336own catalog list if needed.</p> 4337 4338<h4>Preferences setup:</h4> 4339 4340<p>The XML Catalog spec requires the possibility to select default 4341preferences between public and system delegation, 4342xmlCatalogSetDefaultPrefer() allows this, xmlCatalogSetDefaults() and 4343xmlCatalogGetDefaults() allow to control if XML Catalogs resolution should 4344be forbidden, allowed for global catalog, for document catalog or both, the 4345default is to allow both.</p> 4346 4347<p>And of course xmlCatalogSetDebug() allows to generate debug messages 4348(through the xmlGenericError() mechanism).</p> 4349 4350<h4>Querying routines:</h4> 4351 4352<p>xmlCatalogResolve(), xmlCatalogResolveSystem(), xmlCatalogResolvePublic() 4353and xmlCatalogResolveURI() are relatively explicit if you read the XML 4354Catalog specification they correspond to section 7 algorithms, they should 4355also work if you have loaded an SGML catalog with a simplified semantic.</p> 4356 4357<p>xmlCatalogLocalResolve() and xmlCatalogLocalResolveURI() are the same but 4358operate on the document catalog list</p> 4359 4360<h4>Cleanup and Miscellaneous:</h4> 4361 4362<p>xmlCatalogCleanup() free-up the global catalog, xmlCatalogFreeLocal() is 4363the per-document equivalent.</p> 4364 4365<p>xmlCatalogAdd() and xmlCatalogRemove() are used to dynamically modify the 4366first catalog in the global list, and xmlCatalogDump() allows to dump a 4367catalog state, those routines are primarily designed for xmlcatalog, I'm not 4368sure that exposing more complex interfaces (like navigation ones) would be 4369really useful.</p> 4370 4371<p>The xmlParseCatalogFile() is a function used to load XML Catalog files, 4372it's similar as xmlParseFile() except it bypass all catalog lookups, it's 4373provided because this functionality may be useful for client tools.</p> 4374 4375<h4>threaded environments:</h4> 4376 4377<p>Since the catalog tree is built progressively, some care has been taken to 4378try to avoid troubles in multithreaded environments. The code is now thread 4379safe assuming that the libxml2 library has been compiled with threads 4380support.</p> 4381 4382<p></p> 4383 4384<h3><a name="Other">Other resources</a></h3> 4385 4386<p>The XML Catalog specification is relatively recent so there isn't much 4387literature to point at:</p> 4388<ul> 4389 <li>You can find a good rant from Norm Walsh about <a 4390 href="http://www.arbortext.com/Think_Tank/XML_Resources/Issue_Three/issue_three.html">the 4391 need for catalogs</a>, it provides a lot of context information even if 4392 I don't agree with everything presented. Norm also wrote a more recent 4393 article <a 4394 href="http://wwws.sun.com/software/xml/developers/resolver/article/">XML 4395 entities and URI resolvers</a> describing them.</li> 4396 <li>An <a href="http://home.ccil.org/~cowan/XML/XCatalog.html">old XML 4397 catalog proposal</a> from John Cowan</li> 4398 <li>The <a href="http://www.rddl.org/">Resource Directory Description 4399 Language</a> (RDDL) another catalog system but more oriented toward 4400 providing metadata for XML namespaces.</li> 4401 <li>the page from the OASIS Technical <a 4402 href="http://www.oasis-open.org/committees/entity/">Committee on Entity 4403 Resolution</a> who maintains XML Catalog, you will find pointers to the 4404 specification update, some background and pointers to others tools 4405 providing XML Catalog support</li> 4406 <li>There is a <a href="buildDocBookCatalog">shell script</a> to generate 4407 XML Catalogs for DocBook 4.1.2 . If it can write to the /etc/xml/ 4408 directory, it will set-up /etc/xml/catalog and /etc/xml/docbook based on 4409 the resources found on the system. Otherwise it will just create 4410 ~/xmlcatalog and ~/dbkxmlcatalog and doing: 4411 <p><code>export XML_CATALOG_FILES=$HOME/xmlcatalog</code></p> 4412 <p>should allow to process DocBook documentations without requiring 4413 network accesses for the DTD or stylesheets</p> 4414 </li> 4415 <li>I have uploaded <a href="ftp://xmlsoft.org/libxml2/test/dbk412catalog.tar.gz">a 4416 small tarball</a> containing XML Catalogs for DocBook 4.1.2 which seems 4417 to work fine for me too</li> 4418 <li>The <a href="http://www.xmlsoft.org/xmlcatalog_man.html">xmlcatalog 4419 manual page</a></li> 4420</ul> 4421 4422<p>If you have suggestions for corrections or additions, simply contact 4423me:</p> 4424 4425<h2><a name="library">The parser interfaces</a></h2> 4426 4427<p>This section is directly intended to help programmers getting bootstrapped 4428using the XML tollkit from the C language. It is not intended to be 4429extensive. I hope the automatically generated documents will provide the 4430completeness required, but as a separate set of documents. The interfaces of 4431the XML parser are by principle low level, Those interested in a higher level 4432API should <a href="#DOM">look at DOM</a>.</p> 4433 4434<p>The <a href="html/libxml-parser.html">parser interfaces for XML</a> are 4435separated from the <a href="html/libxml-htmlparser.html">HTML parser 4436interfaces</a>. Let's have a look at how the XML parser can be called:</p> 4437 4438<h3><a name="Invoking">Invoking the parser : the pull method</a></h3> 4439 4440<p>Usually, the first thing to do is to read an XML input. The parser accepts 4441documents either from in-memory strings or from files. The functions are 4442defined in "parser.h":</p> 4443<dl> 4444 <dt><code>xmlDocPtr xmlParseMemory(char *buffer, int size);</code></dt> 4445 <dd><p>Parse a null-terminated string containing the document.</p> 4446 </dd> 4447</dl> 4448<dl> 4449 <dt><code>xmlDocPtr xmlParseFile(const char *filename);</code></dt> 4450 <dd><p>Parse an XML document contained in a (possibly compressed) 4451 file.</p> 4452 </dd> 4453</dl> 4454 4455<p>The parser returns a pointer to the document structure (or NULL in case of 4456failure).</p> 4457 4458<h3 id="Invoking1">Invoking the parser: the push method</h3> 4459 4460<p>In order for the application to keep the control when the document is 4461being fetched (which is common for GUI based programs) libxml2 provides a 4462push interface, too, as of version 1.8.3. Here are the interface 4463functions:</p> 4464<pre>xmlParserCtxtPtr xmlCreatePushParserCtxt(xmlSAXHandlerPtr sax, 4465 void *user_data, 4466 const char *chunk, 4467 int size, 4468 const char *filename); 4469int xmlParseChunk (xmlParserCtxtPtr ctxt, 4470 const char *chunk, 4471 int size, 4472 int terminate);</pre> 4473 4474<p>and here is a simple example showing how to use the interface:</p> 4475<pre> FILE *f; 4476 4477 f = fopen(filename, "r"); 4478 if (f != NULL) { 4479 int res, size = 1024; 4480 char chars[1024]; 4481 xmlParserCtxtPtr ctxt; 4482 4483 res = fread(chars, 1, 4, f); 4484 if (res > 0) { 4485 ctxt = xmlCreatePushParserCtxt(NULL, NULL, 4486 chars, res, filename); 4487 while ((res = fread(chars, 1, size, f)) > 0) { 4488 xmlParseChunk(ctxt, chars, res, 0); 4489 } 4490 xmlParseChunk(ctxt, chars, 0, 1); 4491 doc = ctxt->myDoc; 4492 xmlFreeParserCtxt(ctxt); 4493 } 4494 }</pre> 4495 4496<p>The HTML parser embedded into libxml2 also has a push interface; the 4497functions are just prefixed by "html" rather than "xml".</p> 4498 4499<h3 id="Invoking2">Invoking the parser: the SAX interface</h3> 4500 4501<p>The tree-building interface makes the parser memory-hungry, first loading 4502the document in memory and then building the tree itself. Reading a document 4503without building the tree is possible using the SAX interfaces (see SAX.h and 4504<a href="http://www.daa.com.au/~james/gnome/xml-sax/xml-sax.html">James 4505Henstridge's documentation</a>). Note also that the push interface can be 4506limited to SAX: just use the two first arguments of 4507<code>xmlCreatePushParserCtxt()</code>.</p> 4508 4509<h3><a name="Building">Building a tree from scratch</a></h3> 4510 4511<p>The other way to get an XML tree in memory is by building it. Basically 4512there is a set of functions dedicated to building new elements. (These are 4513also described in <libxml/tree.h>.) For example, here is a piece of 4514code that produces the XML document used in the previous examples:</p> 4515<pre> #include <libxml/tree.h> 4516 xmlDocPtr doc; 4517 xmlNodePtr tree, subtree; 4518 4519 doc = xmlNewDoc("1.0"); 4520 doc->children = xmlNewDocNode(doc, NULL, "EXAMPLE", NULL); 4521 xmlSetProp(doc->children, "prop1", "gnome is great"); 4522 xmlSetProp(doc->children, "prop2", "& linux too"); 4523 tree = xmlNewChild(doc->children, NULL, "head", NULL); 4524 subtree = xmlNewChild(tree, NULL, "title", "Welcome to Gnome"); 4525 tree = xmlNewChild(doc->children, NULL, "chapter", NULL); 4526 subtree = xmlNewChild(tree, NULL, "title", "The Linux adventure"); 4527 subtree = xmlNewChild(tree, NULL, "p", "bla bla bla ..."); 4528 subtree = xmlNewChild(tree, NULL, "image", NULL); 4529 xmlSetProp(subtree, "href", "linus.gif");</pre> 4530 4531<p>Not really rocket science ...</p> 4532 4533<h3><a name="Traversing">Traversing the tree</a></h3> 4534 4535<p>Basically by <a href="html/libxml-tree.html">including "tree.h"</a> your 4536code has access to the internal structure of all the elements of the tree. 4537The names should be somewhat simple like <strong>parent</strong>, 4538<strong>children</strong>, <strong>next</strong>, <strong>prev</strong>, 4539<strong>properties</strong>, etc... For example, still with the previous 4540example:</p> 4541<pre><code>doc->children->children->children</code></pre> 4542 4543<p>points to the title element,</p> 4544<pre>doc->children->children->next->children->children</pre> 4545 4546<p>points to the text node containing the chapter title "The Linux 4547adventure".</p> 4548 4549<p><strong>NOTE</strong>: XML allows <em>PI</em>s and <em>comments</em> to be 4550present before the document root, so <code>doc->children</code> may point 4551to an element which is not the document Root Element; a function 4552<code>xmlDocGetRootElement()</code> was added for this purpose.</p> 4553 4554<h3><a name="Modifying">Modifying the tree</a></h3> 4555 4556<p>Functions are provided for reading and writing the document content. Here 4557is an excerpt from the <a href="html/libxml-tree.html">tree API</a>:</p> 4558<dl> 4559 <dt><code>xmlAttrPtr xmlSetProp(xmlNodePtr node, const xmlChar *name, const 4560 xmlChar *value);</code></dt> 4561 <dd><p>This sets (or changes) an attribute carried by an ELEMENT node. 4562 The value can be NULL.</p> 4563 </dd> 4564</dl> 4565<dl> 4566 <dt><code>const xmlChar *xmlGetProp(xmlNodePtr node, const xmlChar 4567 *name);</code></dt> 4568 <dd><p>This function returns a pointer to new copy of the property 4569 content. Note that the user must deallocate the result.</p> 4570 </dd> 4571</dl> 4572 4573<p>Two functions are provided for reading and writing the text associated 4574with elements:</p> 4575<dl> 4576 <dt><code>xmlNodePtr xmlStringGetNodeList(xmlDocPtr doc, const xmlChar 4577 *value);</code></dt> 4578 <dd><p>This function takes an "external" string and converts it to one 4579 text node or possibly to a list of entity and text nodes. All 4580 non-predefined entity references like &Gnome; will be stored 4581 internally as entity nodes, hence the result of the function may not be 4582 a single node.</p> 4583 </dd> 4584</dl> 4585<dl> 4586 <dt><code>xmlChar *xmlNodeListGetString(xmlDocPtr doc, xmlNodePtr list, int 4587 inLine);</code></dt> 4588 <dd><p>This function is the inverse of 4589 <code>xmlStringGetNodeList()</code>. It generates a new string 4590 containing the content of the text and entity nodes. Note the extra 4591 argument inLine. If this argument is set to 1, the function will expand 4592 entity references. For example, instead of returning the &Gnome; 4593 XML encoding in the string, it will substitute it with its value (say, 4594 "GNU Network Object Model Environment").</p> 4595 </dd> 4596</dl> 4597 4598<h3><a name="Saving">Saving a tree</a></h3> 4599 4600<p>Basically 3 options are possible:</p> 4601<dl> 4602 <dt><code>void xmlDocDumpMemory(xmlDocPtr cur, xmlChar**mem, int 4603 *size);</code></dt> 4604 <dd><p>Returns a buffer into which the document has been saved.</p> 4605 </dd> 4606</dl> 4607<dl> 4608 <dt><code>extern void xmlDocDump(FILE *f, xmlDocPtr doc);</code></dt> 4609 <dd><p>Dumps a document to an open file descriptor.</p> 4610 </dd> 4611</dl> 4612<dl> 4613 <dt><code>int xmlSaveFile(const char *filename, xmlDocPtr cur);</code></dt> 4614 <dd><p>Saves the document to a file. In this case, the compression 4615 interface is triggered if it has been turned on.</p> 4616 </dd> 4617</dl> 4618 4619<h3><a name="Compressio">Compression</a></h3> 4620 4621<p>The library transparently handles compression when doing file-based 4622accesses. The level of compression on saves can be turned on either globally 4623or individually for one file:</p> 4624<dl> 4625 <dt><code>int xmlGetDocCompressMode (xmlDocPtr doc);</code></dt> 4626 <dd><p>Gets the document compression ratio (0-9).</p> 4627 </dd> 4628</dl> 4629<dl> 4630 <dt><code>void xmlSetDocCompressMode (xmlDocPtr doc, int mode);</code></dt> 4631 <dd><p>Sets the document compression ratio.</p> 4632 </dd> 4633</dl> 4634<dl> 4635 <dt><code>int xmlGetCompressMode(void);</code></dt> 4636 <dd><p>Gets the default compression ratio.</p> 4637 </dd> 4638</dl> 4639<dl> 4640 <dt><code>void xmlSetCompressMode(int mode);</code></dt> 4641 <dd><p>Sets the default compression ratio.</p> 4642 </dd> 4643</dl> 4644 4645<h2><a name="Entities">Entities or no entities</a></h2> 4646 4647<p>Entities in principle are similar to simple C macros. An entity defines an 4648abbreviation for a given string that you can reuse many times throughout the 4649content of your document. Entities are especially useful when a given string 4650may occur frequently within a document, or to confine the change needed to a 4651document to a restricted area in the internal subset of the document (at the 4652beginning). Example:</p> 4653<pre>1 <?xml version="1.0"?> 46542 <!DOCTYPE EXAMPLE SYSTEM "example.dtd" [ 46553 <!ENTITY xml "Extensible Markup Language"> 46564 ]> 46575 <EXAMPLE> 46586 &xml; 46597 </EXAMPLE></pre> 4660 4661<p>Line 3 declares the xml entity. Line 6 uses the xml entity, by prefixing 4662its name with '&' and following it by ';' without any spaces added. There 4663are 5 predefined entities in libxml2 allowing you to escape characters with 4664predefined meaning in some parts of the xml document content: 4665<strong>&lt;</strong> for the character '<', <strong>&gt;</strong> 4666for the character '>', <strong>&apos;</strong> for the character ''', 4667<strong>&quot;</strong> for the character '"', and 4668<strong>&amp;</strong> for the character '&'.</p> 4669 4670<p>One of the problems related to entities is that you may want the parser to 4671substitute an entity's content so that you can see the replacement text in 4672your application. Or you may prefer to keep entity references as such in the 4673content to be able to save the document back without losing this usually 4674precious information (if the user went through the pain of explicitly 4675defining entities, he may have a a rather negative attitude if you blindly 4676substitute them as saving time). The <a 4677href="html/libxml-parser.html#xmlSubstituteEntitiesDefault">xmlSubstituteEntitiesDefault()</a> 4678function allows you to check and change the behaviour, which is to not 4679substitute entities by default.</p> 4680 4681<p>Here is the DOM tree built by libxml2 for the previous document in the 4682default case:</p> 4683<pre>/gnome/src/gnome-xml -> ./xmllint --debug test/ent1 4684DOCUMENT 4685version=1.0 4686 ELEMENT EXAMPLE 4687 TEXT 4688 content= 4689 ENTITY_REF 4690 INTERNAL_GENERAL_ENTITY xml 4691 content=Extensible Markup Language 4692 TEXT 4693 content=</pre> 4694 4695<p>And here is the result when substituting entities:</p> 4696<pre>/gnome/src/gnome-xml -> ./tester --debug --noent test/ent1 4697DOCUMENT 4698version=1.0 4699 ELEMENT EXAMPLE 4700 TEXT 4701 content= Extensible Markup Language</pre> 4702 4703<p>So, entities or no entities? Basically, it depends on your use case. I 4704suggest that you keep the non-substituting default behaviour and avoid using 4705entities in your XML document or data if you are not willing to handle the 4706entity references elements in the DOM tree.</p> 4707 4708<p>Note that at save time libxml2 enforces the conversion of the predefined 4709entities where necessary to prevent well-formedness problems, and will also 4710transparently replace those with chars (i.e. it will not generate entity 4711reference elements in the DOM tree or call the reference() SAX callback when 4712finding them in the input).</p> 4713 4714<p><span style="background-color: #FF0000">WARNING</span>: handling entities 4715on top of the libxml2 SAX interface is difficult!!! If you plan to use 4716non-predefined entities in your documents, then the learning curve to handle 4717then using the SAX API may be long. If you plan to use complex documents, I 4718strongly suggest you consider using the DOM interface instead and let libxml 4719deal with the complexity rather than trying to do it yourself.</p> 4720 4721<h2><a name="Namespaces">Namespaces</a></h2> 4722 4723<p>The libxml2 library implements <a 4724href="http://www.w3.org/TR/REC-xml-names/">XML namespaces</a> support by 4725recognizing namespace constructs in the input, and does namespace lookup 4726automatically when building the DOM tree. A namespace declaration is 4727associated with an in-memory structure and all elements or attributes within 4728that namespace point to it. Hence testing the namespace is a simple and fast 4729equality operation at the user level.</p> 4730 4731<p>I suggest that people using libxml2 use a namespace, and declare it in the 4732root element of their document as the default namespace. Then they don't need 4733to use the prefix in the content but we will have a basis for future semantic 4734refinement and merging of data from different sources. This doesn't increase 4735the size of the XML output significantly, but significantly increases its 4736value in the long-term. Example:</p> 4737<pre><mydoc xmlns="http://mydoc.example.org/schemas/"> 4738 <elem1>...</elem1> 4739 <elem2>...</elem2> 4740</mydoc></pre> 4741 4742<p>The namespace value has to be an absolute URL, but the URL doesn't have to 4743point to any existing resource on the Web. It will bind all the element and 4744attributes with that URL. I suggest to use an URL within a domain you 4745control, and that the URL should contain some kind of version information if 4746possible. For example, <code>"http://www.gnome.org/gnumeric/1.0/"</code> is a 4747good namespace scheme.</p> 4748 4749<p>Then when you load a file, make sure that a namespace carrying the 4750version-independent prefix is installed on the root element of your document, 4751and if the version information don't match something you know, warn the user 4752and be liberal in what you accept as the input. Also do *not* try to base 4753namespace checking on the prefix value. <foo:text> may be exactly the 4754same as <bar:text> in another document. What really matters is the URI 4755associated with the element or the attribute, not the prefix string (which is 4756just a shortcut for the full URI). In libxml, element and attributes have an 4757<code>ns</code> field pointing to an xmlNs structure detailing the namespace 4758prefix and its URI.</p> 4759 4760<p>@@Interfaces@@</p> 4761<pre>xmlNodePtr node; 4762if(!strncmp(node->name,"mytag",5) 4763 && node->ns 4764 && !strcmp(node->ns->href,"http://www.mysite.com/myns/1.0")) { 4765 ... 4766}</pre> 4767 4768<p>Usually people object to using namespaces together with validity checking. 4769I will try to make sure that using namespaces won't break validity checking, 4770so even if you plan to use or currently are using validation I strongly 4771suggest adding namespaces to your document. A default namespace scheme 4772<code>xmlns="http://...."</code> should not break validity even on less 4773flexible parsers. Using namespaces to mix and differentiate content coming 4774from multiple DTDs will certainly break current validation schemes. To check 4775such documents one needs to use schema-validation, which is supported in 4776libxml2 as well. See <a href="http://www.relaxng.org/">relagx-ng</a> and <a 4777href="http://www.w3c.org/XML/Schema">w3c-schema</a>.</p> 4778 4779<h2><a name="Upgrading">Upgrading 1.x code</a></h2> 4780 4781<p>Incompatible changes:</p> 4782 4783<p>Version 2 of libxml2 is the first version introducing serious backward 4784incompatible changes. The main goals were:</p> 4785<ul> 4786 <li>a general cleanup. A number of mistakes inherited from the very early 4787 versions couldn't be changed due to compatibility constraints. Example 4788 the "childs" element in the nodes.</li> 4789 <li>Uniformization of the various nodes, at least for their header and link 4790 parts (doc, parent, children, prev, next), the goal is a simpler 4791 programming model and simplifying the task of the DOM implementors.</li> 4792 <li>better conformances to the XML specification, for example version 1.x 4793 had an heuristic to try to detect ignorable white spaces. As a result the 4794 SAX event generated were ignorableWhitespace() while the spec requires 4795 character() in that case. This also mean that a number of DOM node 4796 containing blank text may populate the DOM tree which were not present 4797 before.</li> 4798</ul> 4799 4800<h3>How to fix libxml-1.x code:</h3> 4801 4802<p>So client code of libxml designed to run with version 1.x may have to be 4803changed to compile against version 2.x of libxml. Here is a list of changes 4804that I have collected, they may not be sufficient, so in case you find other 4805change which are required, <a href="mailto:Daniel.Veillard@w3.org">drop me a 4806mail</a>:</p> 4807<ol> 4808 <li>The package name have changed from libxml to libxml2, the library name 4809 is now -lxml2 . There is a new xml2-config script which should be used to 4810 select the right parameters libxml2</li> 4811 <li>Node <strong>childs</strong> field has been renamed 4812 <strong>children</strong> so s/childs/children/g should be applied 4813 (probability of having "childs" anywhere else is close to 0+</li> 4814 <li>The document don't have anymore a <strong>root</strong> element it has 4815 been replaced by <strong>children</strong> and usually you will get a 4816 list of element here. For example a Dtd element for the internal subset 4817 and it's declaration may be found in that list, as well as processing 4818 instructions or comments found before or after the document root element. 4819 Use <strong>xmlDocGetRootElement(doc)</strong> to get the root element of 4820 a document. Alternatively if you are sure to not reference DTDs nor have 4821 PIs or comments before or after the root element 4822 s/->root/->children/g will probably do it.</li> 4823 <li>The white space issue, this one is more complex, unless special case of 4824 validating parsing, the line breaks and spaces usually used for indenting 4825 and formatting the document content becomes significant. So they are 4826 reported by SAX and if your using the DOM tree, corresponding nodes are 4827 generated. Too approach can be taken: 4828 <ol> 4829 <li>lazy one, use the compatibility call 4830 <strong>xmlKeepBlanksDefault(0)</strong> but be aware that you are 4831 relying on a special (and possibly broken) set of heuristics of 4832 libxml to detect ignorable blanks. Don't complain if it breaks or 4833 make your application not 100% clean w.r.t. to it's input.</li> 4834 <li>the Right Way: change you code to accept possibly insignificant 4835 blanks characters, or have your tree populated with weird blank text 4836 nodes. You can spot them using the commodity function 4837 <strong>xmlIsBlankNode(node)</strong> returning 1 for such blank 4838 nodes.</li> 4839 </ol> 4840 <p>Note also that with the new default the output functions don't add any 4841 extra indentation when saving a tree in order to be able to round trip 4842 (read and save) without inflating the document with extra formatting 4843 chars.</p> 4844 </li> 4845 <li>The include path has changed to $prefix/libxml/ and the includes 4846 themselves uses this new prefix in includes instructions... If you are 4847 using (as expected) the 4848 <pre>xml2-config --cflags</pre> 4849 <p>output to generate you compile commands this will probably work out of 4850 the box</p> 4851 </li> 4852 <li>xmlDetectCharEncoding takes an extra argument indicating the length in 4853 byte of the head of the document available for character detection.</li> 4854</ol> 4855 4856<h3>Ensuring both libxml-1.x and libxml-2.x compatibility</h3> 4857 4858<p>Two new version of libxml (1.8.11) and libxml2 (2.3.4) have been released 4859to allow smooth upgrade of existing libxml v1code while retaining 4860compatibility. They offers the following:</p> 4861<ol> 4862 <li>similar include naming, one should use 4863 <strong>#include<libxml/...></strong> in both cases.</li> 4864 <li>similar identifiers defined via macros for the child and root fields: 4865 respectively <strong>xmlChildrenNode</strong> and 4866 <strong>xmlRootNode</strong></li> 4867 <li>a new macro <strong>LIBXML_TEST_VERSION</strong> which should be 4868 inserted once in the client code</li> 4869</ol> 4870 4871<p>So the roadmap to upgrade your existing libxml applications is the 4872following:</p> 4873<ol> 4874 <li>install the libxml-1.8.8 (and libxml-devel-1.8.8) packages</li> 4875 <li>find all occurrences where the xmlDoc <strong>root</strong> field is 4876 used and change it to <strong>xmlRootNode</strong></li> 4877 <li>similarly find all occurrences where the xmlNode 4878 <strong>childs</strong> field is used and change it to 4879 <strong>xmlChildrenNode</strong></li> 4880 <li>add a <strong>LIBXML_TEST_VERSION</strong> macro somewhere in your 4881 <strong>main()</strong> or in the library init entry point</li> 4882 <li>Recompile, check compatibility, it should still work</li> 4883 <li>Change your configure script to look first for xml2-config and fall 4884 back using xml-config . Use the --cflags and --libs output of the command 4885 as the Include and Linking parameters needed to use libxml.</li> 4886 <li>install libxml2-2.3.x and libxml2-devel-2.3.x (libxml-1.8.y and 4887 libxml-devel-1.8.y can be kept simultaneously)</li> 4888 <li>remove your config.cache, relaunch your configuration mechanism, and 4889 recompile, if steps 2 and 3 were done right it should compile as-is</li> 4890 <li>Test that your application is still running correctly, if not this may 4891 be due to extra empty nodes due to formating spaces being kept in libxml2 4892 contrary to libxml1, in that case insert xmlKeepBlanksDefault(1) in your 4893 code before calling the parser (next to 4894 <strong>LIBXML_TEST_VERSION</strong> is a fine place).</li> 4895</ol> 4896 4897<p>Following those steps should work. It worked for some of my own code.</p> 4898 4899<p>Let me put some emphasis on the fact that there is far more changes from 4900libxml 1.x to 2.x than the ones you may have to patch for. The overall code 4901has been considerably cleaned up and the conformance to the XML specification 4902has been drastically improved too. Don't take those changes as an excuse to 4903not upgrade, it may cost a lot on the long term ...</p> 4904 4905<h2><a name="Thread">Thread safety</a></h2> 4906 4907<p>Starting with 2.4.7, libxml2 makes provisions to ensure that concurrent 4908threads can safely work in parallel parsing different documents. There is 4909however a couple of things to do to ensure it:</p> 4910<ul> 4911 <li>configure the library accordingly using the --with-threads options</li> 4912 <li>call xmlInitParser() in the "main" thread before using any of the 4913 libxml2 API (except possibly selecting a different memory allocator)</li> 4914</ul> 4915 4916<p>Note that the thread safety cannot be ensured for multiple threads sharing 4917the same document, the locking must be done at the application level, libxml 4918exports a basic mutex and reentrant mutexes API in <libxml/threads.h>. 4919The parts of the library checked for thread safety are:</p> 4920<ul> 4921 <li>concurrent loading</li> 4922 <li>file access resolution</li> 4923 <li>catalog access</li> 4924 <li>catalog building</li> 4925 <li>entities lookup/accesses</li> 4926 <li>validation</li> 4927 <li>global variables per-thread override</li> 4928 <li>memory handling</li> 4929</ul> 4930 4931<p>XPath is supposed to be thread safe now, but this wasn't tested 4932seriously.</p> 4933 4934<h2><a name="DOM"></a><a name="Principles">DOM Principles</a></h2> 4935 4936<p><a href="http://www.w3.org/DOM/">DOM</a> stands for the <em>Document 4937Object Model</em>; this is an API for accessing XML or HTML structured 4938documents. Native support for DOM in Gnome is on the way (module gnome-dom), 4939and will be based on gnome-xml. This will be a far cleaner interface to 4940manipulate XML files within Gnome since it won't expose the internal 4941structure.</p> 4942 4943<p>The current DOM implementation on top of libxml2 is the <a 4944href="http:///svn.gnome.org/viewcvs/gdome2/trunk/">gdome2 Gnome module</a>, this 4945is a full DOM interface, thanks to Paolo Casarini, check the <a 4946href="http://gdome2.cs.unibo.it/">Gdome2 homepage</a> for more 4947information.</p> 4948 4949<h2><a name="Example"></a><a name="real">A real example</a></h2> 4950 4951<p>Here is a real size example, where the actual content of the application 4952data is not kept in the DOM tree but uses internal structures. It is based on 4953a proposal to keep a database of jobs related to Gnome, with an XML based 4954storage structure. Here is an <a href="gjobs.xml">XML encoded jobs 4955base</a>:</p> 4956<pre><?xml version="1.0"?> 4957<gjob:Helping xmlns:gjob="http://www.gnome.org/some-location"> 4958 <gjob:Jobs> 4959 4960 <gjob:Job> 4961 <gjob:Project ID="3"/> 4962 <gjob:Application>GBackup</gjob:Application> 4963 <gjob:Category>Development</gjob:Category> 4964 4965 <gjob:Update> 4966 <gjob:Status>Open</gjob:Status> 4967 <gjob:Modified>Mon, 07 Jun 1999 20:27:45 -0400 MET DST</gjob:Modified> 4968 <gjob:Salary>USD 0.00</gjob:Salary> 4969 </gjob:Update> 4970 4971 <gjob:Developers> 4972 <gjob:Developer> 4973 </gjob:Developer> 4974 </gjob:Developers> 4975 4976 <gjob:Contact> 4977 <gjob:Person>Nathan Clemons</gjob:Person> 4978 <gjob:Email>nathan@windsofstorm.net</gjob:Email> 4979 <gjob:Company> 4980 </gjob:Company> 4981 <gjob:Organisation> 4982 </gjob:Organisation> 4983 <gjob:Webpage> 4984 </gjob:Webpage> 4985 <gjob:Snailmail> 4986 </gjob:Snailmail> 4987 <gjob:Phone> 4988 </gjob:Phone> 4989 </gjob:Contact> 4990 4991 <gjob:Requirements> 4992 The program should be released as free software, under the GPL. 4993 </gjob:Requirements> 4994 4995 <gjob:Skills> 4996 </gjob:Skills> 4997 4998 <gjob:Details> 4999 A GNOME based system that will allow a superuser to configure 5000 compressed and uncompressed files and/or file systems to be backed 5001 up with a supported media in the system. This should be able to 5002 perform via find commands generating a list of files that are passed 5003 to tar, dd, cpio, cp, gzip, etc., to be directed to the tape machine 5004 or via operations performed on the filesystem itself. Email 5005 notification and GUI status display very important. 5006 </gjob:Details> 5007 5008 </gjob:Job> 5009 5010 </gjob:Jobs> 5011</gjob:Helping></pre> 5012 5013<p>While loading the XML file into an internal DOM tree is a matter of 5014calling only a couple of functions, browsing the tree to gather the data and 5015generate the internal structures is harder, and more error prone.</p> 5016 5017<p>The suggested principle is to be tolerant with respect to the input 5018structure. For example, the ordering of the attributes is not significant, 5019the XML specification is clear about it. It's also usually a good idea not to 5020depend on the order of the children of a given node, unless it really makes 5021things harder. Here is some code to parse the information for a person:</p> 5022<pre>/* 5023 * A person record 5024 */ 5025typedef struct person { 5026 char *name; 5027 char *email; 5028 char *company; 5029 char *organisation; 5030 char *smail; 5031 char *webPage; 5032 char *phone; 5033} person, *personPtr; 5034 5035/* 5036 * And the code needed to parse it 5037 */ 5038personPtr parsePerson(xmlDocPtr doc, xmlNsPtr ns, xmlNodePtr cur) { 5039 personPtr ret = NULL; 5040 5041DEBUG("parsePerson\n"); 5042 /* 5043 * allocate the struct 5044 */ 5045 ret = (personPtr) malloc(sizeof(person)); 5046 if (ret == NULL) { 5047 fprintf(stderr,"out of memory\n"); 5048 return(NULL); 5049 } 5050 memset(ret, 0, sizeof(person)); 5051 5052 /* We don't care what the top level element name is */ 5053 cur = cur->xmlChildrenNode; 5054 while (cur != NULL) { 5055 if ((!strcmp(cur->name, "Person")) && (cur->ns == ns)) 5056 ret->name = xmlNodeListGetString(doc, cur->xmlChildrenNode, 1); 5057 if ((!strcmp(cur->name, "Email")) && (cur->ns == ns)) 5058 ret->email = xmlNodeListGetString(doc, cur->xmlChildrenNode, 1); 5059 cur = cur->next; 5060 } 5061 5062 return(ret); 5063}</pre> 5064 5065<p>Here are a couple of things to notice:</p> 5066<ul> 5067 <li>Usually a recursive parsing style is the more convenient one: XML data 5068 is by nature subject to repetitive constructs and usually exhibits highly 5069 structured patterns.</li> 5070 <li>The two arguments of type <em>xmlDocPtr</em> and <em>xmlNsPtr</em>, 5071 i.e. the pointer to the global XML document and the namespace reserved to 5072 the application. Document wide information are needed for example to 5073 decode entities and it's a good coding practice to define a namespace for 5074 your application set of data and test that the element and attributes 5075 you're analyzing actually pertains to your application space. This is 5076 done by a simple equality test (cur->ns == ns).</li> 5077 <li>To retrieve text and attributes value, you can use the function 5078 <em>xmlNodeListGetString</em> to gather all the text and entity reference 5079 nodes generated by the DOM output and produce an single text string.</li> 5080</ul> 5081 5082<p>Here is another piece of code used to parse another level of the 5083structure:</p> 5084<pre>#include <libxml/tree.h> 5085/* 5086 * a Description for a Job 5087 */ 5088typedef struct job { 5089 char *projectID; 5090 char *application; 5091 char *category; 5092 personPtr contact; 5093 int nbDevelopers; 5094 personPtr developers[100]; /* using dynamic alloc is left as an exercise */ 5095} job, *jobPtr; 5096 5097/* 5098 * And the code needed to parse it 5099 */ 5100jobPtr parseJob(xmlDocPtr doc, xmlNsPtr ns, xmlNodePtr cur) { 5101 jobPtr ret = NULL; 5102 5103DEBUG("parseJob\n"); 5104 /* 5105 * allocate the struct 5106 */ 5107 ret = (jobPtr) malloc(sizeof(job)); 5108 if (ret == NULL) { 5109 fprintf(stderr,"out of memory\n"); 5110 return(NULL); 5111 } 5112 memset(ret, 0, sizeof(job)); 5113 5114 /* We don't care what the top level element name is */ 5115 cur = cur->xmlChildrenNode; 5116 while (cur != NULL) { 5117 5118 if ((!strcmp(cur->name, "Project")) && (cur->ns == ns)) { 5119 ret->projectID = xmlGetProp(cur, "ID"); 5120 if (ret->projectID == NULL) { 5121 fprintf(stderr, "Project has no ID\n"); 5122 } 5123 } 5124 if ((!strcmp(cur->name, "Application")) && (cur->ns == ns)) 5125 ret->application = xmlNodeListGetString(doc, cur->xmlChildrenNode, 1); 5126 if ((!strcmp(cur->name, "Category")) && (cur->ns == ns)) 5127 ret->category = xmlNodeListGetString(doc, cur->xmlChildrenNode, 1); 5128 if ((!strcmp(cur->name, "Contact")) && (cur->ns == ns)) 5129 ret->contact = parsePerson(doc, ns, cur); 5130 cur = cur->next; 5131 } 5132 5133 return(ret); 5134}</pre> 5135 5136<p>Once you are used to it, writing this kind of code is quite simple, but 5137boring. Ultimately, it could be possible to write stubbers taking either C 5138data structure definitions, a set of XML examples or an XML DTD and produce 5139the code needed to import and export the content between C data and XML 5140storage. This is left as an exercise to the reader :-)</p> 5141 5142<p>Feel free to use <a href="example/gjobread.c">the code for the full C 5143parsing example</a> as a template, it is also available with Makefile in the 5144Gnome SVN base under libxml2/example</p> 5145 5146<h2><a name="Contributi">Contributions</a></h2> 5147<ul> 5148 <li>Bjorn Reese, William Brack and Thomas Broyer have provided a number of 5149 patches, Gary Pennington worked on the validation API, threading support 5150 and Solaris port.</li> 5151 <li>John Fleck helps maintaining the documentation and man pages.</li> 5152 <li><a href="mailto:igor@zlatkovic.com">Igor Zlatkovic</a> is now the 5153 maintainer of the Windows port, <a 5154 href="http://www.zlatkovic.com/projects/libxml/index.html">he provides 5155 binaries</a></li> 5156 <li><a href="mailto:Gary.Pennington@sun.com">Gary Pennington</a> provides 5157 <a href="http://garypennington.net/libxml2/">Solaris binaries</a></li> 5158 <li><a 5159 href="http://mail.gnome.org/archives/xml/2001-March/msg00014.html">Matt 5160 Sergeant</a> developed <a 5161 href="http://axkit.org/download/">XML::LibXSLT</a>, a Perl wrapper for 5162 libxml2/libxslt as part of the <a href="http://axkit.com/">AxKit XML 5163 application server</a></li> 5164 <li><a href="mailto:fnatter@gmx.net">Felix Natter</a> and <a 5165 href="mailto:geertk@ai.rug.nl">Geert Kloosterman</a> provide <a 5166 href="libxml-doc.el">an emacs module</a> to lookup libxml(2) functions 5167 documentation</li> 5168 <li><a href="mailto:sherwin@nlm.nih.gov">Ziying Sherwin</a> provided <a 5169 href="http://xmlsoft.org/messages/0488.html">man pages</a></li> 5170 <li>there is a module for <a 5171 href="http://acs-misc.sourceforge.net/nsxml.html">libxml/libxslt support 5172 in OpenNSD/AOLServer</a></li> 5173 <li><a href="mailto:dkuhlman@cutter.rexx.com">Dave Kuhlman</a> provided the 5174 first version of libxml/libxslt <a 5175 href="http://www.rexx.com/~dkuhlman">wrappers for Python</a></li> 5176 <li>Petr Kozelka provides <a 5177 href="http://sourceforge.net/projects/libxml2-pas">Pascal units to glue 5178 libxml2</a> with Kylix and Delphi and other Pascal compilers</li> 5179 <li><a href="mailto:aleksey@aleksey.com">Aleksey Sanin</a> implemented the 5180 <a href="http://www.w3.org/Signature/">XML Canonicalization and XML 5181 Digital Signature</a> <a 5182 href="http://www.aleksey.com/xmlsec/">implementations for libxml2</a></li> 5183 <li><a href="mailto:Steve.Ball@explain.com.au">Steve Ball</a> and 5184 contributors maintain <a href="http://tclxml.sourceforge.net/">tcl 5185 bindings for libxml2 and libxslt</a>, as well as <a 5186 href="http://tclxml.sf.net/tkxmllint.html">tkxmllint</a> a GUI for 5187 xmllint and <a href="http://tclxml.sf.net/tkxsltproc.html">tkxsltproc</a> 5188 a GUI for xsltproc.</li> 5189</ul> 5190 5191<p></p> 5192</body> 5193</html> 5194
